Prediction of postoperative pulmonary complications in a population-based surgical cohort. Anesthesiology. 2010;113:1338-1350. [PMID: 21045639 DOI: 10.1097/aln.0b013e3181fc6e0a]

Electrical impedance tomography-guided positive end-expiratory pressure titration for perioperative oxygenation and postoperative pulmonary complications: A systematic review and meta-analysis

BACKGROUND

The electrical impedance tomography (EIT)-guided individual positive end-expiratory pressure (PEEP) approach is a noninvasive, radiation-free, and straightforward strategy. However, its validity to prevent postoperative complications remains unclear. To determine whether the EIT-guided PEEP titration in surgery has a higher oxygenation index and lower postoperative complications incidence in patients, we performed a meta-analysis to assess the efficacy. The study design is a systematic review and meta-analysis.

METHODS

Four databases (Cochrane, PubMed, Web of Science, and Embase) were searched from 2000 to November 2022 for this study. Randomized controlled trials of patients selected for general anesthesia were included. The main indicators of the study were oxygenation and postoperative pulmonary complications. Study quality was assessed using the Cochrane Risk and Bias Tool.

RESULTS

A total of 7 articles with 425 subjects were included and were eligible for analysis. Meta-analysis showed that patients had a higher oxygenation index (PaO2/FiO2) after EIT-guided individual PEEP titration compared with other modalities of PEEP titration (6 trials, 351 subjects, standardized mean check = 1.06, 95% confidence interval = 0.59-1.53). For subgroup analysis, the results were still statistically significant both in adult/elder groups and normal/obese groups. No significant advantage was found for the incidence of postoperative pulmonary complications between individual PEEP titration under EIT and other titration strategies (5 trials, 341 subjects, standardized mean check = 0.77, 95% confidence interval = 0.34-1.71). The same results were found in the subgroup analysis.

CONCLUSION

EIT-guided individual PEEP setting significantly improved perioperative oxygenation index compared with other modalities of PEEP ventilation strategies for patients, but no significant differences were found in the incidence of the postoperative pulmonary complications.

Electrical Impedance Tomography-Based Evaluation of Anesthesia-Induced Development of Atelectasis in Obese Patients

Background/Objectives: The induction of general anesthesia leads to the development of atelectasis and redistribution of ventilation to non-dependent lung regions with subsequent impairment of gas exchange. However, it remains unclear how rapidly atelectasis occurs after the induction of anesthesia in obese patients. We therefore investigated the extent of atelectasis formation in obese patients in the first few minutes after the induction of general anesthesia and initiation of mechanical ventilation in the operating room. Methods: In 102 patients with morbid obesity (BMI ≥ 35 kg m-2) scheduled for laparoscopic intrabdominal surgery, induction of general anesthesia was performed while continuously monitoring regional pulmonary ventilation using electrical impedance tomography. Distribution of ventilation to non-dependent lung areas as a surrogate for atelectasis formation was determined by taking the mean value of five consecutive breaths for each minute starting five minutes before to five minutes after intubation. Ventilation inhomogeneity was assessed using the Global Inhomogeneity Index. Results: Median tidal volume in non-dependent lung areas was 58.3% before and 71.5% after intubation and increased by a median of 13.79% after intubation (p < 0.001). Median Global Inhomogeneity Index was 49.4 before and 71.4 after intubation and increased by a median of 21.99 units after intubation (p < 0.001). Conclusions: Atelectasis forms immediately after the induction of general anesthesia and increases the inhomogeneity of lung ventilation.

Can the lung ultrasound score predict pulmonary complications after non-thoracic surgery in patients with blunt thoracic trauma: A single-center observational study

STUDY OBJECTIVE

Patients with blunt thoracic trauma have a high risk of developing postoperative pulmonary complications (PPCs). In this study, we aimed to identify the risk factors for PPCs after non-thoracic surgery in patients with blunt thoracic trauma and investigate the efficacy of perioperative lung ultrasound scores in predicting PPC occurrence.

DESIGN

Prospective observational study.

SETTING

A Chinese tertiary orthopedic hospital.

PARTICIPANTS

This observational study included 369 patients with blunt thoracic trauma who underwent surgery for pelvic and upper or lower extremity fractures.

INTERVENTIONS

Lung ultrasonography was performed pre- and postoperatively.

MEASUREMENTS

Patients were followed up for 1 week to assess PPCs and assigned to the PPC or non-PPC groups. We identified risk factors for PPCs using univariate and multivariate logistic regression analyses. The predictive value of these risk factors was evaluated using receiver operating characteristic (ROC) curves.

MAIN RESULTS

PPCs incidence was 36.58 %. The two groups differed significantly in Injury Severity Scores, American Society of Anesthesiologists (ASA) classification, chronic obstructive pulmonary disease, hydrothorax, preoperative hypoxemia, lung ultrasound score, preoperative hemoglobin level, intraoperative infusion volume, and Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) scores (P < 0.05). Independent risk factors for PPCs included ASA classification III, higher postoperative lung ultrasound scores, preoperative anemia, higher intraoperative infusion volume, and higher ARISCAT scores. ROC curve analysis revealed that postoperative lung ultrasound score (area under the curve [AUC]: 0.810, cutoff: 10), preoperative hemoglobin level (AUC: 0.627, cutoff: 97), intraoperative infusion volume (AUC: 0.701, cutoff: 886.51 mL/h) and ARISCAT score (AUC: 0.718, cutoff: 33) predicted postoperative outcomes effectively.

CONCLUSIONS

Postoperative lung ultrasound scores reliably predicted pulmonary complications after non-thoracic surgery in patients with blunt thoracic trauma. ASA classification III, preoperative anemia, excessive intraoperative fluid infusion, higher ARISCAT, and postoperative lung ultrasound scores were significant risk factors associated with PPCs.

TRIAL REGISTRATION

Clinical Trial Number: 1900023408. Registered on May 26, 2019.

Effect of inspiratory oxygen fraction during driving pressure-guided ventilation strategy on pulmonary complications following open abdominal surgery: A randomized controlled trial

STUDY OBJECTIVE

The aim of the present study was to determine the effect of 30 % fraction of inspired oxygen (FIO2) compared with 80 % FIO2 in the context of driving pressure-guided ventilation strategy on pulmonary complications following open abdominal surgery.

DESIGN

A single-center, prospective, randomized controlled trial.

SETTING

Tertiary university hospital in China.

PATIENTS

514 adult patients, ASA I-III and scheduled for major open abdominal surgery under general anesthesia.

INTERVENTIONS

Patients were randomly assigned to receive either 30 % or 80 % FIO2 during the intraoperative period. All patients received driving pressure-guided ventilation strategy, including low tidal volume and individualized PEEP set at lowest driving pressure.

MEASUREMENTS

The primary outcome was the incidence of a composite of pulmonary complications within the 7 days postoperatively. The severity of pulmonary complications, extrapulmonary complications, and other secondary outcomes were also assessed.

MAIN RESULTS

Of 1553 patients assessed for eligibility, 514 patients were randomly assigned and analyzed with intention-to-treat principle. Patients receiving 30 % FIO2 had a significantly lower incidence of postoperative pulmonary complications (PPCs) compared to those receiving 80 % FIO2 (46.3 %vs. 64.6 %; RR, 0.72; 95 % CI, 0.61-0.84; P < 0.001). The severity score of PPCs was significantly reduced in the 30 % FIO2 group compared with that in the 80 % FIO2 group within the 7 postoperative days (P < 0.001). Dynamic compliance was significantly greater in 30 % FIO2 group at the end of surgery (56 [48-66] vs. 53 [46-62], P = 0.027). More patients in the 80 % FIO2 group developed oxygen desaturation (SpO2 < 94 %) on air intake during PACU stay (18.5 %vs. 30.4 %; RR, 0.61; 95 % CI, 0.44-0.84; P = 0.002; 30 % FIO2 group vs.80 % FIO2 group).

CONCLUSIONS

In patients undergoing open abdominal surgery, using a 30 % FIO2, compared with 80 % FIO2, in context of driving pressure-guided ventilation strategy, intraoperatively reduced the incidence and severity of pulmonary complications within the first 7 postoperative days.

Lung-protective ventilation and postoperative pulmonary complications during pulmonary resection in children: A prospective, single-centre, randomised controlled trial

BACKGROUND

Children are more susceptible to postoperative pulmonary complications (PPCs) due to their smaller functional residual capacity and higher closing volume; however, lung-protective ventilation (LPV) in children requiring one-lung ventilation (OLV) has been relatively underexplored.

OBJECTIVES

To evaluate the effects of LPV and driving pressure-guided ventilation on PPCs in children with OLV.

DESIGN

Randomised, controlled, double-blind study.

SETTING

Single-site tertiary hospital, 6 May 2022 to 31 August 2023.

PATIENTS

213 children aged < 6 years, planned for lung resection secondary to congenital cystic adenomatoid malformation.

INTERVENTIONS

Children were randomly assigned to LPV ( n  = 142) or control ( n  = 71) groups. Children in LPV group were randomly assigned to either driving pressure group ( n  = 70) receiving individualised positive end-expiratory pressure (PEEP) to deliver the lowest driving pressure or to conventional protective ventilation group ( n  = 72) with fixed PEEP of 5 cmH 2 O.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of PPCs within 7 days after surgery. Secondary outcomes were pulmonary mechanics, oxygenation and mechanical power.

RESULTS

The incidence of PPCs did not differ between the LPV (24/142, 16.9%) and the control groups (15/71, 21.1%) ( P  = 0.45). The driving pressure was lower in the driving pressure group than in the 5 cmH 2 O PEEP group (15 vs. 17 cmH 2 O; P   =  0.001). Lung compliance and oxygenation were higher while the dynamic component of mechanical power was lower in the driving pressure group than in the 5 cmH 2 O PEEP group. The incidence of PPCs did not differ between the driving pressure (11/70, 15.7%) and the 5 cmH 2 O PEEP groups (13/72, 18.1%) ( P   =  0.71).

CONCLUSIONS

LPV did not decrease the occurrence of PPCs compared to non-protective ventilation. Although lung compliance and oxygenation were higher in the driving pressure group than in the 5 cmH 2 O PEEP group, these benefits did not translate into significant reductions in PPCs. However, the study is limited by a small sample size, which may affect the interpretation of the results. Future research with larger sample sizes is necessary to confirm these findings.

TRIAL REGISTRATION

ChiCTR2200059270.

Effect of ventilation mode on postoperative pulmonary complications among intermediate- to high-risk patients undergoing abdominal surgery: A randomized controlled trial

BACKGROUND

The effect of different mechanical ventilation modes on pulmonary outcome after abdominal surgery remains unclear. We evaluated the effects of three common ventilation modes on postoperative pulmonary complications (PPCs) among intermediate- to high-risk patients undergoing abdominal surgery.

METHODS

This randomized clinical trial enrolled adult patients at intermediate or high risk of PPCs who were scheduled for abdominal surgery. Participants were randomized to receive one of three modes of mechanical ventilation modes: volume-controlled ventilation (VCV), pressure-controlled ventilation (PCV), and pressure-control with volume-guaranteed ventilation (PCV-VG). Lung-protective ventilation strategy was implemented in all groups. The primary outcome was the incidence of a composite of pulmonary complications within the first 7 postoperative days. Pulmonary complications within 30 postoperative days, the severity grade of PPCs, and other secondary outcomes were also analyzed.

RESULTS

A total of 1365 patients were randomized and 1349 were analyzed. The primary outcome occurred in 98 (21.8%) in the VCV group, 95 (22.1%) in the PCV group, and 101 (22.5%) in the PCV-VG group (P = 0.865). Additionally, there were no statistically significant differences among the three groups in terms of the incidence of pulmonary complications within postoperative 30 days, severity grade of PPCs, and other secondary outcomes.

CONCLUSION

In intermediate- to high-risk patients undergoing abdominal surgery, the choice of ventilation mode did not affect the risk of PPCs.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, entry ChiCTR1900025880.

Integrating StEP-COMPAC definition and enhanced recovery after surgery status in a machine-learning-based model for postoperative pulmonary complications in laparoscopic hepatectomy

BACKGROUND

Postoperative pulmonary complications (PPCs) contribute to high mortality rates and impose significant financial burdens. In this study, a machine learning-based prediction model was developed to identify patients at high risk of developing PPCs following laparoscopic hepatectomy.

METHODS

Data were collected from 1022 adult patients who underwent laparoscopic hepatectomy at two centres between January 2015 and February 2021. The dataset was divided into a development set and a temporal external validation set based on the year of surgery. A total of 42 factors were extracted for pre-modelling, including the implementation status of Enhanced Recovery after Surgery (ERAS). Feature selection was performed using the least absolute shrinkage and selection operator (LASSO) method. Model performance was assessed using the area under the receiver operating characteristic curve (AUC). The model with the best performance was externally validated using temporal data.

RESULTS

The incidence of PPCs was 8.7%. Lambda.1se was selected as the optimal lambda for LASSO feature selection. For implementation of ERAS, serum gamma-glutamyl transferase levels, malignant tumour presence, total bilirubin levels, and age-adjusted Charleston Comorbidities Index were the selected factors. Seven models were developed. Among them, logistic regression demonstrated the best performance, with an AUC of 0.745 in the internal validation set and 0.680 in the temporal external validation set.

CONCLUSIONS

Based on the most recent definition, a machine learning model was employed to predict the risk of PPCs following laparoscopic hepatectomy. Logistic regression was identified as the best-performing model. ERAS implementation was associated with a reduction in the number of PPCs.

Effect of low-dose norepinephrine combined with goal-directed fluid therapy on postoperative pulmonary complications in lung surgery: A prospective randomized controlled trial

STUDY OBJECTIVE

Postoperative pulmonary complications (PPCs), the predominant complications following lung surgery, are closely associated with intraoperative fluid therapy. This study investigates whether continuous low-dose norepinephrine infusion combined with goal-directed fluid therapy (GDFT) reduced the risk of PPCs after lung surgery relative to either GDFT alone or standard fluid treatment.

DESIGN

A prospective, randomized controlled trial.

SETTING

The First Affiliated Hospital of Anhui Medical University, Anhui, China.

PATIENTS

The study included 184 patients undergoing elective thoracoscopic lung resection surgery.

INTERVENTIONS

Patients were randomized into three groups based on different fluid treatment regimens: Group C received standard fluid treatment, Group G received GDFT, and Group N received continuous low-dose norepinephrine infusion combined with GDFT.

MEASUREMENTS

The primary outcome was the incidence of PPCs, including respiratory infection, atelectasis, pneumothorax, pleural empyema, respiratory failure, pulmonary embolism and bronchopleural fistula, during the postoperative hospital stay. Secondary outcomes were hemodynamic variables and arterial blood gases. Additional recorded parameters included other postoperative complications such as bleeding, postoperative re-intubation, re-hospitalization within 30 days, and the length of hospital stay.

MAIN RESULTS

Group N showed a significantly lower PPCs incidence during hospitalization compared to Group C (11.5 % vs 27.9 %; odds ratio, 2.98; 95 % confidence interval, 1.17-8.31; P = 0.023). No significant difference in PPCs was found between Group N and Group G (11.5 % vs 14.5 %; odds ratio, 1.31; 95 % confidence interval, 0.46-3.91; P = 0.616). Additionally, there were no significant differences among the three groups in the components of PPCs. Group N showed higher mean arterial pressure and stroke volume index intraoperatively compared to Group C.

CONCLUSIONS

Continuous low-dose norepinephrine infusion combined with GDFT reduced PPCs incidence in elective lung surgery patients compared with standard fluid management, but showed no difference compared to GDFT alone.

CLINICAL TRIAL REGISTRATION

ChiCTR2200064081.

Sex dependence of postoperative pulmonary complications - A post hoc unmatched and matched analysis of LAS VEGAS

STUDY OBJECTIVE

Male sex has inconsistently been associated with the development of postoperative pulmonary complications (PPCs). These studies were different in size, design, population and preoperative risk. We reanalysed the database of 'Local ASsessment of Ventilatory management during General Anaesthesia for Surgery study' (LAS VEGAS) to evaluate differences between females and males with respect to PPCs.

DESIGN, SETTING AND PATIENTS

Post hoc unmatched and matched analysis of LAS VEGAS, an international observational study in patients undergoing intraoperative ventilation under general anaesthesia for surgery in 146 hospitals across 29 countries. The primary endpoint was a composite of PPCs in the first 5 postoperative days. Individual PPCs, hospital length of stay and mortality were secondary endpoints. Propensity score matching was used to create a similar cohort regarding type of surgery and epidemiological factors with a known association with development of PPCs.

MAIN RESULTS

The unmatched cohort consisted of 9697 patients; 5342 (55.1%) females and 4355 (44.9%) males. The matched cohort consisted of 6154 patients; 3077 (50.0%) females and 3077 (50.0%) males. The incidence in PPCs was neither significant between females and males in the unmatched cohort (10.0 vs 10.7%; odds ratio (OR) 0.93 [0.81-1.06]; P = 0.255), nor in the matched cohort (10.5 vs 10.0%; OR 1.05 [0.89-1.25]; P = 0.556). New invasive ventilation occurred less often in females in the unmatched cohort. Hospital length of stay and mortality were similar between females and males in both cohorts.

CONCLUSIONS

In this conveniently-sized worldwide cohort of patients receiving intraoperative ventilation under general anaesthesia for surgery, the PPC incidence was not significantly different between sexes.

REGISTRATION

LAS VEGAS was registered at clinicaltrial.gov (study identifier NCT01601223).

Association between thoracic epidural anesthesia and driving pressure in adult patients undergoing elective major upper abdominal surgery: a randomized controlled trial

BACKGROUND

Thoracic epidural anesthesia (TEA) is associated with a knowledge gap regarding its mechanisms in lung protection and reduction of postoperative pulmonary complications (PPCs). Driving pressure (ΔP), an alternative indicator of alveolar strain, is closely linked to reduced PPCs with lower ΔP values. We aim to investigate whether TEA contributes to lung protection by lowering ΔP during mechanical ventilation.

METHODS

In this prospective, randomized, patient and evaluator-blinded parallel study, adult patients scheduled for elective major upper abdominal surgery were assigned to either the TEA group with combined thoracic epidural anesthesia and general anesthesia (TEA-GA) (n = 30) or the control group with only general anesthesia (GA) (n = 30).

MEASUREMENTS

The primary outcome was the minimum ΔP determined based on positive end-expiratory pressure (PEEP) after intubation. Secondary outcomes included the incidence of PPCs within seven days, the minimum ΔP at various time points, blood gas analysis, intensive care unit (ICU) admission rates, length of hospital stay, and 30-day mortality rate.

RESULTS

The TEA group had a significantly lower minimum ΔP titrated based on PEEP compared to the control group (11.23 ± 2.19 cmH2O vs. 12.67 ± 2.70 cmH2O; P = 0.028). Multivariate linear regression analysis showed that intraoperative TEA application (compared with its absence; unstandardized beta coefficient (B) = -1.289; P = 0.008) significantly correlated with ΔP. The incidence of PPCs did not differ significantly between the two groups (8 of 30 [26.7%] vs. 12 of 30 [40%]; P = 0.273), but the incidence of atelectasis in the TEA group was significantly lower than in the control group (5 of 30 [16.7%] vs. 12 of 30 [40.7%]; P = 0.012). Multivariate logistic regression analysis indicated that ΔP was the only variable significantly associated with PPCs (Adjusted Odds Ratio [OR] = 2.190; 95% Confidence Interval [CI]: 1.300 to 3.689; P = 0.003).

CONCLUSION

Compared to GA, TEA-GA can reduce intraoperative ΔP in patients undergoing major upper abdominal surgery, especially those undergoing laparoscopic surgery. However, compared to GA combined with ΔP-guided ventilation, TEA-GA combined with ΔP-guided ventilation does not reduce the risk of PPCs. There was no significant difference in the total use of various vasoactive drugs between the two groups.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (registration number ChiCTR2300068778 date of registration February 28, 2023).

Perioperative Lung Ultrasound Findings in Elective Intra-Abdominal Surgery: Associations with Postoperative Pulmonary Complications

Background: For patients undergoing abdominal surgery, postoperative pulmonary complications (PPCs) are a major source of morbidity and mortality. The use of point-of-care ultrasonography (POCUS), and specifically POCUS of the lungs, has seen many advancements in recent years. Objectives: We hypothesize that perioperative lung ultrasonography can be used as a predictor for PPCs. Methods: In a Single, 1000 beds, trauma level I medical center, patients presenting for elective intra-abdominal surgery with no severe pulmonary or cardiac diseases were evaluated preoperatively with a standardized 12-point lung ultrasound exam. A second identical exam was performed after surgery in the post-anesthesia care unit. PPCs were also documented. All lung ultrasound exams were presented to a blinded researcher and a lung ultrasound score (LUS) was calculated. Statistical analysis comparing pre- and postoperative LUS and PPC scores were performed. Results: A total of 61 patients were evaluated. The pre-surgery median LUS was 0 (in the range of 0-6) and the post-surgery median LUS was 3 (in the range of 0-14). The pre- to postsurgical LUS delta was 3.4 (standard deviation of 3.3). A postoperative LUS of 6 or more was defined as "high." A High LUS did not correlate with prolonged post-anesthesia care unit or hospital stay, prolonged oxygen support, or number of desaturation events. Conclusion: For elective abdominal surgery in relatively healthy patients, preoperative LUS usually begins at a normal level and becomes worse after general anesthesia. However, this difference in LUS is not significantly associated with clinically relevant postoperative pulmonary complications such as prolonged oxygen therapy, pneumonia, and noninvasive or invasive mechanical ventilation. Trial registration: Clinicaltrials.gov identifier: NCT05502926. Summary: This paper explores the use of point-of-care ultrasonography as a predictor for postoperative pulmonary complications. The findings suggest that while the lung ultrasound score worsens with general anesthesia, the differences are not significantly associated with postoperative pulmonary complications.

Effect of ultrasound-guided individualized positive end-expiratory pressure on the severity of postoperative atelectasis in elderly patients: a randomized controlled study

Postoperative pulmonary complications (PPCs) are common in patients undergoing general anesthesia, with atelectasis being a key contributor that increases postoperative mortality and prolongs hospitalization. Our research hypothesis is that ultrasound-guided individualized PEEP titration can reduce postoperative atelectasis. This single-center randomized controlled trial recruited elderly patients for laparoscopic surgery. Patients were randomly assigned to two group: the study group (individualized PEEP groups, PEEP Ind group) and the control group (Fixed PEEP group, PEEP 5 group). All patients in these two groups received volume-controlled ventilation during general anesthesia. Patients in the study group were given ultrasound-guided PEEP, while those in the control group were given a fixed 5 cmH2O PEEP. Bedside ultrasound assessed lung ventilation. The primary outcome was the severity of atelectasis within seven days post-surgery. Eighty-nine patients scheduled for elective laparoscopic radical surgery for colorectal cancer were enrolled in our study. Lung ultrasound scores (LUSs) in the study group during postoperative seven days was significantly decreased compared with that in the control group (P < 0.05). The severity of postoperative atelectasis in the study group was significantly improved. The incidence of PPCs during postoperative 7 days in the study group was significantly less than that in the control group (48.6% vs. 77.8%; RR = 0.625; CI = 0.430-0.909; P = 0.01). In elderly patients undergoing laparoscopic radical resection, lung ultrasound-guided individualized PEEP can alleviate the severity of postoperative atelectasis.Clinical trial number and registry URL: No. ChiCTR2200062979 ( https://www.chictr.org.cn ).

Impact and effect of preoperative short-term preoperative pulmonary-related training on patients with gastric cancer: a randomized controlled single center trial

PURPOSE

This study aimed is to evaluate the impact of pre- and postoperative pulmonary-related training, including respiratory and aerobic training, on postoperative pulmonary complications (PPCs) after radical resection of gastric cancer (GC).

METHODS

We conducted a randomized controlled trial of 121 participants who received a systematic, comprehensive, high-intensity pulmonary exercise regimen for 5 days preoperatively and at least 5 days postoperatively. The control group received standard preoperative care. We analyzed the occurrence of PPCs in both groups as the primary outcome RESULTS: A total of 43 of 121 participants (35.5%) were diagnosed as having PPCs, and the incidence of PPCs was markedly lower in the training group than in the control group (26.2% [16 of 61] vs 45.0% [27 of 60]; P = .031). Moreover, the duration of the postoperative hospital stay was shorter in the training group (8.69 ± 1.92 days) than the control group (9.57 ± 2.16 days; P = .020) and reduced hospitalization costs, amounting to €9605.1 ± €2556.26 in the training group and €10,594.6 ± €2560.7 in the control group (P = .035).

CONCLUSION

Our study established that a perioperative pulmonary-related training notably diminishes the incidence of PPCs, curtails the duration of hospitalization, and mitigates hospitalization expenses for patients undergoing GC surgery.

The association between intraoperative low driving pressure ventilation and perioperative healthcare-associated costs: A retrospective multicenter cohort study

STUDY OBJECTIVE

A low dynamic driving pressure during mechanical ventilation for general anesthesia has been associated with a lower risk of postoperative respiratory complications (PRC), a key driver of healthcare costs. It is, however, unclear whether maintaining low driving pressure is clinically relevant to measure and contain costs. We hypothesized that a lower dynamic driving pressure is associated with lower costs.

DESIGN

Multicenter retrospective cohort study.

SETTING

Two academic healthcare networks in New York and Massachusetts, USA.

PATIENTS

46,715 adult surgical patients undergoing general anesthesia for non-ambulatory (inpatient and same-day admission) surgery between 2016 and 2021.

INTERVENTIONS

The primary exposure was the median intraoperative dynamic driving pressure.

MEASUREMENTS

The primary outcome was direct perioperative healthcare-associated costs, which were matched with data from the Healthcare Cost and Utilization Project-National Inpatient Sample (HCUP-NIS) to report absolute differences in total costs in United States Dollars (US$). We assessed effect modification by patients' baseline risk of PRC (score for prediction of postoperative respiratory complications [SPORC] ≥ 7) and effect mediation by rates of PRC (including post-extubation saturation < 90%, re-intubation or non-invasive ventilation within 7 days) and other major complications.

MAIN RESULTS

The median intraoperative dynamic driving pressure was 17.2cmH2O (IQR 14.0-21.3cmH2O). In adjusted analyses, every 5cmH2O reduction in dynamic driving pressure was associated with a decrease of -0.7% in direct perioperative healthcare-associated costs (95%CI -1.3 to -0.1%; p = 0.020). When a dynamic driving pressure below 15cmH2O was maintained, -US$340 lower total perioperative healthcare-associated costs were observed (95%CI -US$546 to -US$132; p = 0.001). This association was limited to patients at high baseline risk of PRC (n = 4059; -US$1755;97.5%CI -US$2495 to -US$986; p < 0.001), where lower risks of PRC and other major complications mediated 10.7% and 7.2% of this association (p < 0.001 and p = 0.015, respectively).

CONCLUSIONS

Intraoperative mechanical ventilation targeting low dynamic driving pressures could be a relevant measure to reduce perioperative healthcare-associated costs in high-risk patients.

Machine learning and preoperative risk prediction: the machines are coming

Preoperative risk prediction is an important component of perioperative medicine. Machine learning is a powerful tool that could lead to increasingly complex risk prediction models with improved predictive performance. Careful consideration is required to guide the machine learning approach to ensure appropriate decisions are made with regard to what we are trying to predict, when we are trying to predict it, and what we seek to do with the results.

Evaluation and Management of Perioperative Pulmonary Complications

Pulmonary complications are very common after noncardiac surgery and can be easily overlooked. If not properly screened for or evaluated these can in many instances lead to postoperative respiratory failure or even death. Decisions regarding ambulatory versus inpatient surgery, modality of anesthesia, protective ventilation and method of weaning, type of analgesia, and postoperative monitoring can be crucial to avoid such complications.

ClC-1 Inhibition as a Mechanism for Accelerating Skeletal Muscle Recovery After Neuromuscular Block in Rats

Neuromuscular blocking agents are used commonly to induce skeletal muscle relaxation during surgery. While muscle relaxation facilitates surgical procedures and tracheal intubation, adequate recovery of muscle function after surgery is required to support pulmonary function, and even mild residual neuromuscular block increases the risk of severe postoperative pulmonary complications. While recovery of muscle function after surgery involving neuromuscular blocking agents can be monitored and, in addition, be accelerated by use of current antagonists (reversal agents), there is a clear clinical need for a safe drug to antagonize all types of neuromuscular blocking agents. Here, we show that inhibition of the skeletal muscle-specific chloride ion (Cl-) channel, the ClC-1 channel, markedly accelerates recovery of both single contraction (twitch) and, important physiologically, sustained (tetanic) contractions in a rat model mimicking neuromuscular blocking agent-induced muscle block used during surgery. This suggests ClC-1 inhibition as a mechanism for fast and efficacious recovery of neuromuscular function induced by any neuromuscular blocking agents.

Driving pressure during general anesthesia for minimally invasive abdominal surgery (GENERATOR)-study protocol of a randomized clinical trial

BACKGROUND

Intraoperative driving pressure (ΔP) has an independent association with the development of postoperative pulmonary complications (PPCs) in patients receiving ventilation during general anesthesia for major surgery. Ventilation with high intraoperative positive end-expiratory pressure (PEEP) with recruitment maneuvers (RMs) that result in a low ΔP has the potential to prevent PPCs. This trial tests the hypothesis that compared to standard low PEEP without RMs, an individualized high PEEP strategy, titrated to the lowest ΔP, with RMs prevents PPCs in patients receiving intraoperative protective ventilation during anesthesia for minimally invasive abdominal surgery.

METHODS

"DrivinG prEssure duriNg gEneRal AnesThesia fOr minimally invasive abdominal suRgery (GENERATOR)" is an international, multicenter, two-group, patient and outcome-assessor blinded randomized clinical trial. In total, 1806 adult patients scheduled for minimally invasive abdominal surgery and with an increased risk of PPCs based on (i) the ARISCAT risk score for PPCs (≥ 26 points) and/or (ii) a combination of age > 40 years and scheduled surgery lasting > 2 h and planned to receive an intra-arterial catheter for blood pressure monitoring during the surgery will be included. Patients are assigned to either an intraoperative ventilation strategy with individualized high PEEP, titrated to the lowest ΔP, with RMs or one with a standard low PEEP of 5 cm H2O without RMs. The primary outcome is a collapsed composite endpoint of PPCs until postoperative day 5.

DISCUSSION

GENERATOR will be the first adequately powered randomized clinical trial to compare the effects of individualized high PEEP with RMs versus standard low PEEP without RMs on the occurrence of PPCs after minimally invasive abdominal surgery. The results of the GENERATOR trial will support anesthesiologists in their decisions regarding PEEP settings during minimally invasive abdominal surgery.

TRIAL REGISTRATION

GENERATOR is registered at ClinicalTrials.gov (study identifier: NCT06101511) on 26 October 2023.

Higher fraction of inspired oxygen during anesthesia increase the risk of postoperative pulmonary complications in patients undergoing non-cardiothoracic surgery: a retrospective cohort study

Objective

The ideal intra-operative inspired oxygen concentration remains controversial. We aimed to investigate the association between the intraoperative fraction of inspired oxygen (FiO2) and the incidence of postoperative pulmonary complications (PPCs) in patients undergoing non-cardiothoracic surgery.

Methods

This was a retrospective cohort study of elderly patients who underwent non-cardiothoracic surgery between April 2020 and January 2022. According to intraoperative FiO2, patients were divided into low (≤60%) and high (>60%) FiO2 groups. The primary outcome was the incidence of a composite of pulmonary complications (PPCs) within the first seven postoperative days. Propensity score matching (PSM) and inverse probability treatment weighting (IPTW) were conducted to adjust for baseline characteristic differences between the two groups. Multivariate logistic regression analysis was used to calculate the odds ratios (OR) for FiO2 and PPCs.

Results

Among the 3,515 included patients with a median age of 70 years (interquartile range: 68-74), 492 (14%) experienced PPCs within the first 7 postoperative days. Elevated FiO2 was associated with an increased risk of PPCs in all the logistic regression models. The OR of the FiO2 > 60% group was 1.252 (95%CI, 1.015-1.551, P = 0.038) in the univariate analysis. In the multivariate logistic regression models, the ORs of the FiO2 > 60% group were 1.259 (Model 2), 1.314 (Model 3), and 1.32 (model 4). A balanced covariate distribution between the two groups was created using PSM or IPTW. The correlation between elevated FiO2 and an increased risk of PPCs remained statistically significant with PSM analysis (OR, 1.393; 95% CI, 1.077-1.804; P = 0.012) and IPTW analysis (OR, 1.266; 95% CI, 1.086-1.476; P = 0.003).

Conclusion

High intraoperative FiO2 (>60%) was associated with the postoperative occurrence of pulmonary complications, independent of predefined risk factors, in elderly non-cardiothoracic surgery patients. High intraoperative FiO2 should be applied cautiously in surgical patients vulnerable to PPCs.

Enhancing Thoracic Surgery with AI: A Review of Current Practices and Emerging Trends

Artificial intelligence (AI) is increasingly becoming integral to medical practice, potentially enhancing outcomes in thoracic surgery. AI-driven models have shown significant accuracy in diagnosing non-small-cell lung cancer (NSCLC), predicting lymph node metastasis, and aiding in the efficient extraction of electronic medical record (EMR) data. Moreover, AI applications in robotic-assisted thoracic surgery (RATS) and perioperative management reveal the potential to improve surgical precision, patient safety, and overall care efficiency. Despite these advancements, challenges such as data privacy, biases, and ethical concerns remain. This manuscript explores AI applications, particularly machine learning (ML) and natural language processing (NLP), in thoracic surgery, emphasizing their role in diagnosis and perioperative management. It also provides a comprehensive overview of the current state, benefits, and limitations of AI in thoracic surgery, highlighting future directions in the field.

Development and validation of a nomogram for predicting pulmonary complications in elderly patients undergoing thoracic surgery

BACKGROUND

Postoperative pulmonary complications (PPCs) remain a prevalent concern among elderly patients undergoing surgery, with a notably higher incidence observed in elderly patients undergoing thoracic surgery. This study aimed to develop a nomogram to predict the risk of PPCs in this population.

METHODS

A total of 2963 elderly patients who underwent thoracic surgery were enrolled and randomly divided into a training cohort (80%, n = 2369) or a validation cohort (20%, n = 593). Univariate and multivariate logistic regression analyses were conducted to identify risk factors for PPCs, and a nomogram was developed based on the findings from the training cohort. The validation cohort was used to validate the model. The predictive accuracy of the model was evaluated by receiver operating characteristic (ROC) curve, area under ROC (AUC), calibration curve, and decision curve analysis (DCA).

RESULTS

A total of 918 (31.0%) patients reported PPCs. Nine independent risk factors for PPCs were identified: preoperative presence of chronic obstructive pulmonary disease (COPD), elevated leukocyte count, higher partial pressure of arterial carbon dioxide (PaCO2) level, surgical site, thoracotomy, intraoperative hypotension, blood loss > 100 mL, surgery duration > 180 min, and malignant tumor. The AUC value for the training cohort was 0.739 (95% CI: 0.719-0.762), and it was 0.703 for the validation cohort (95% CI: 0.657-0.749). The P-values for the Hosmer-Lemeshow test were 0.633 and 0.144 for the training and validation cohorts, respectively, indicating a notable calibration curve fit. The DCA curve indicated that the nomogram could be applied clinically if the risk threshold was between 12% and 84%, which was found to be between 8% and 82% in the validation cohort.

CONCLUSION

This study highlighted the pressing need for early detection of PPCs in elderly patients undergoing thoracic surgery. The nomogram exhibited promising predictive efficacy for PPCs in elderly patients undergoing thoracic surgery, enabling the identification of high-risk patients and consequently aiding in the implementation of preventive interventions.

Risk of pulmonary complications after video-assisted thoracoscopic pulmonary resection in children

BACKGROUND

Postoperative pulmonary complications (PPCs) are associated with high mortality and morbidity rates. Children are more susceptible to PPCs owing to smaller functional residual capacity and greater closing volume. Risk factors of PPCs in children undergoing lung resection remain unclear.

METHODS

This retrospective study enrolled children who underwent video-assisted thoracoscopic surgery between January 2018 and February 2023. The primary outcome was PPC occurrence. Multivariate logistic regression was used to analyze risk factors for PPCs.

RESULTS

Overall, 640 children were analyzed; their median age was 7 (interquartile range: 5-11) months, and the median tidal volume was 7.66 (6.59-8.49) mL/kg. One hundred and seventeen (18.3%) developed PPCs. PPCs were independently associated with male sex (odds ratio [OR], 1.83; 95% confidence interval [CI], 1.17-2.88; P=0.008), longer OLV duration (OR, 1.01; 95% CI, 1.0-1.01; P=0.001), and less surgeon's experience (OR, 1.67; 95% CI, 1.03-2.7; P=0.036). When low-tidal-volume cutoff was defined as <8 mL/kg, PEEP level was a protective factor for PPCs (OR, 0.83; 95% CI, 0.69-1.00; P=0.046). Additionally, PPCs were associated with increased hospital stay (P<0.001).

CONCLUSIONS

Male sex, longer OLV duration, less surgeon's experience, and lower PEEP were risk factors of PPCs in children undergoing video-assisted thoracoscopic surgery. Our findings may serve as targets for prospective studies investigating specific ventilation strategies for children.

Incidence of postoperative pulmonary complications and associated risk factors after major oncosurgeries: Prospective observational study

BACKGROUND

Postoperative pulmonary complications (PPCs) are defined heterogeneously and have major adverse effects in increasing morbidity. Oncosurgeries themselves are complex, are of long duration, and extensive handling of body tissues occurs in them, leading to various complications including PPCs. So, we conducted this prospective study intending to find the incidence and risk factors for PPCs in patients undergoing major oncosurgeries.

METHODS

This prospective observational study was conducted after obtaining institutional ethical approval in patients undergoing major oncosurgeries. The demographic, preoperative, and intraoperative details were noted, and patients were followed in the postoperative period for the occurrence of PPC till discharge. Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score was used to predict the occurrence of PPC. Data were analyzed using multivariable regression analysis for the risk factors, and the Chi-square trend was used to see the trend of PPC with the change in ARISCAT score.

RESULTS

The overall incidence of PPC in patients undergoing major oncosurgeries was 28.05%. The most common PPCs were respiratory insufficiency (19.2%) and atelectasis (17.6%). The highest incidence of PPC was found in thoracotomies (41.6%), followed by cytoreductive surgeries (40.6%). The risk factors for PPCs included body mass index (BMI) <18.5 or >25 kg/m2, smoking, use of nasogastric tube, age >60 years, and albumin <3.5 g/dL. Patients with low ARISCAT scores had a low incidence of PPC compared to those with high and intermediate ARISCAT scores.

CONCLUSION

The incidence of PPC in patients undergoing major oncosurgeries was 28.05% in our study. The independent risk factors for PPC in oncological surgeries were BMI <18.5 kg/m2 or >25 kg/m2, use of nasogastric tube, age <60 years, serum albumin <3.5 g/dL, and smoking.

Intraoperative Ventilation/Perfusion Mismatch and Postoperative Pulmonary Complications after Major Noncardiac Surgery: A Prospective Cohort Study

BACKGROUND

Postoperative pulmonary complications can increase hospital length of stay, postoperative morbidity, and mortality. Although many factors can increase the risk of postoperative pulmonary complications, it is not known whether intraoperative ventilation/perfusion (V/Q) mismatch can be associated with an increased risk of postoperative pulmonary complications after major noncardiac surgery.

METHODS

This study enrolled patients undergoing general anesthesia for noncardiac surgery and evaluated intraoperative V/Q distribution using the automatic lung parameter estimator technique. The assessment was done after anesthesia induction, after 1 h from surgery start, and at the end of surgery. Demographic and procedural information were collected, and intraoperative ventilatory and hemodynamic parameters were measured at each timepoint. Patients were followed up for 7 days after surgery and assessed daily for postoperative pulmonary complication occurrence.

RESULTS

The study enrolled 101 patients with a median age of 71 [62 to 77] years, a body mass index of 25 [22.4 to 27.9] kg/m2, and a preoperative Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score of 41 [34 to 47]. Of these patients, 29 (29%) developed postoperative pulmonary complications, mainly acute respiratory failure (23%) and pleural effusion (11%). Patients with and without postoperative pulmonary complications did not differ in levels of shunt at T1 (postoperative pulmonary complications: 22.4% [10.4 to 35.9%] vs. no postoperative pulmonary complications:19.3% [9.4 to 24.1%]; P = 0.18) or during the protocol, whereas significantly different levels of high V/Q ratio were found during surgery (postoperative pulmonary complications: 13 [11 to 15] mmHg vs. no postoperative pulmonary complications: 10 [8 to 13.5] mmHg; P = 0.007) and before extubation (postoperative pulmonary complications: 13 [11 to 14] mmHg vs. no postoperative pulmonary complications: 10 [8 to 12] mmHg; P = 0.006). After adjusting for age, ARISCAT, body mass index, smoking, fluid balance, anesthesia type, laparoscopic procedure and surgery duration, high V/Q ratio before extubation was independently associated with the development of postoperative pulmonary complications (odds ratio, 1.147; 95% CI, 1.021 to 1.289; P = 0.02). The sensitivity analysis showed an E-value of 1.35 (CI, 1.11).

CONCLUSIONS

In patients with intermediate or high risk of postoperative pulmonary complications undergoing major noncardiac surgery, intraoperative V/Q mismatch is associated with the development of postoperative pulmonary complications. Increased high V/Q ratio before extubation is independently associated with the occurrence of postoperative pulmonary complications in the first 7 days after surgery.

EDITOR’S PERSPECTIVE

Effect of preoperative natural killer cell on postoperative pulmonary complications in patients of lung cancer - A single-center retrospective cohort study

BACKGROUND

The effect of preoperative natural killer (NK) cell abnormalities on postoperative pulmonary complications (PPCs) after thoracoscopic radical resection of lung cancer is still unclear. The main purpose of this study was to investigate the relationship between the preoperative NK cell ratio and PPCs.

METHODS

The patients who underwent thoracoscopic radical resection for lung cancer were divided into a normal group and an abnormal group according to whether the proportion of preoperative NK cells was within the reference range. The main outcome was the incidence of PPCs during postoperative hospitalization. The demographic and perioperative data were collected. Propensity score matching was used to exclude systematic bias. Univariate logistic regression was used to test the relationship between the preoperative NK cell ratio and the incidence of PPCs. The restrictive cubic spline curve was used to analyze the dose-effect relationship between the preoperative NK cell ratio and the incidence of PPCs.

RESULTS

A total of 4161 patients were included. After establishing a matching cohort, 910 patients were included in the statistical analysis. The incidence of PPCs in the abnormal group was greater than that in the normal group (55.2% vs. 31.6%). The incidence of PPCs first decreased and then increased with increasing NK cell ratio. The proportion of patients with Grade 3 or higher PPCs in the normal group was lower than that in the abnormal group [108 (23.7%) vs. 223 (49%)]. The indwelling time of the thoracic drainage tube in the abnormal group was longer than that in the normal group [3 (3, 4) vs. 3 (3, 5)]. A preoperative abnormal NK cell ratio constituted a risk factor for PPCs in each subgroup.

CONCLUSION

Lung cancer patients with an abnormal proportion of peripheral blood NK cells before surgery were more likely to develop PPCs, their disease degree was more severe, and they had a prolonged duration of chest tube indwelling. Compared with those with abnormally high NK cell ratios, those with abnormally low NK cell ratios had more pronounced PPCs.

Postoperative pulmonary complications after major abdominal surgery in elderly patients and its association with patient-controlled analgesia

OBJECTIVES

This study aims to identify the risk factors for postoperative pulmonary complications (PPCs) in elderly patients undergoing major abdominal surgery and to investigate the relationship between patient-controlled analgesia (PCA) and PPCs.

DESIGN

A retrospective study.

METHOD

Clinical data and demographic information of elderly patients (aged ≥ 60 years) who underwent upper abdominal surgery at the First Affiliated Hospital of Sun Yat-sen University from 2017 to 2019 were retrospectively collected. Patients with PPCs were identified using the Melbourne Group Scale Version 2 scoring system. A directed acyclic graph was used to identify the potential confounders, and multivariable logistic regression analyses were conducted to identify independent risk factors for PPCs. Propensity score matching was utilized to compare PPC rates between patients with and without PCA, as well as between intravenous PCA (PCIA) and epidural PCA (PCEA) groups.

RESULTS

A total of 1,467 patients were included, with a PPC rate of 8.7%. Multivariable analysis revealed that PCA was an independent protective factor for PPCs in elderly patients undergoing major abdominal surgery (odds ratio = 0.208, 95% confidence interval = 0.121 to 0.358; P < 0.001). After matching, patients receiving PCA demonstrated a significantly lower overall incidence of PPCs (8.6% vs. 26.3%, P < 0.001), unplanned transfer to the intensive care unit (1.1% vs. 8.4%, P = 0.001), and in-hospital mortality (0.7% vs. 5.3%, P = 0.021) compared to those not receiving PCA. No significant difference in outcomes was observed between patients receiving PCIA or PCEA after matching.

CONCLUSION

Patient-controlled analgesia, whether administered intravenously or epidurally, is associated with a reduced risk of PPCs in elderly patients undergoing major upper abdominal surgery.

Effect of Volatile Anesthesia Versus Intravenous Anesthesia on Postoperative Pulmonary Complications in Patients Undergoing Minimally Invasive Esophagectomy: A Randomized Clinical Trial

BACKGROUND

The effect of intraoperative anesthetic regimen on pulmonary outcome after minimally invasive esophagectomy for esophageal cancer is yet undetermined. The aim of this study was to determine the effect of volatile anesthesia (sevoflurane or desflurane) compared with propofol-based intravenous anesthesia on pulmonary complications after minimally invasive esophagectomy.

METHODS

Patients scheduled for minimally invasive esophagectomy were randomly assigned to 1 of 3 general anesthetic regimens (sevoflurane, desflurane, or propofol). The primary outcome was the incidence of pulmonary complications within the 7 days postoperatively, which was a collapsed composite end point, including respiratory infection, pleural effusion, pneumothorax, atelectasis, respiratory failure, bronchospasm, pulmonary embolism, and aspiration pneumonitis. The severity of pulmonary complications, surgery-related complications, and other secondary outcomes were also assessed.

RESULTS

Of 647 patients assessed for eligibility, 558 were randomized, and 553 were analyzed. A total of 185 patients were assigned to the sevoflurane group, 185 in the desflurane, and 183 in the propofol group. Patients receiving a volatile anesthetic (sevoflurane or desflurane) had a significantly lower incidence (36.5% vs 47.5%; odds ratio, 0.63; 95% confidence interval, 0.44-0.91; P = .013) and lower severity grade of pulmonary complications ( P = .035) compared to the patients receiving propofol. There were no statistically significant differences in other secondary outcomes between the 2 groups.

CONCLUSIONS

In patients undergoing minimally invasive esophagectomy, the use of volatile anesthesia (sevoflurane or desflurane) resulted in the reduced risk and severity of pulmonary complications within the first 7 postoperative days as compared to propofol-based intravenous anesthesia.

External validation of the CARDOT score for predicting respiratory complications after thoracic surgery

BACKGROUND

The CARDOT scores have been developed for prediction of respiratory complications after thoracic surgery. This study aimed to externally validate the CARDOT score and assess the predictive value of preoperative neutrophil-to-lymphocyte ratio (NLR) for postoperative respiratory complication.

METHODS

A retrospective cohort study of consecutive thoracic surgical patients at a single tertiary hospital in northern Thailand was conducted. The development and validation datasets were collected between 2006 and 2012 and from 2015 to 2021, respectively. Six prespecified predictive factors were identified, and formed a predictive score, the CARDOT score (chronic obstructive pulmonary disease, American Society of Anesthesiologists physical status, right-sided operation, duration of surgery, preoperative oxygen saturation on room air, thoracotomy), was calculated. The performance of the CARDOT score was evaluated in terms of discrimination by using the area under the receiver operating characteristic (AuROC) curve and calibration.

RESULTS

There were 1086 and 1645 patients included in the development and validation datasets. The incidence of respiratory complications was 15.7% (171 of 1086) and 22.5% (370 of 1645) in the development and validation datasets, respectively. The CARDOT score had good discriminative ability for both the development and validation datasets (AuROC 0.789 (95% CI 0.753-0.827) and 0.758 (95% CI 0.730-0.787), respectively). The CARDOT score showed good calibration in both datasets. A high NLR (≥ 4.5) significantly increased the risk of respiratory complications after thoracic surgery (P < 0.001). The AuROC curve of the validation cohort increased to 0.775 (95% CI 0.750-0.800) when the score was combined with a high NLR. The AuROC of the CARDOT score with the NLR showed significantly greater discrimination power than that of the CARDOT score alone (P = 0.008).

CONCLUSIONS

The CARDOT score showed a good discriminative performance in the external validation dataset. An addition of a high NLR significantly increases the predictive performance of CARDOT score. The utility of this score is valuable in settings with limited access to preoperative pulmonary function testing.

Prediction models for postoperative pulmonary complications in intensive care unit patients after noncardiac thoracic surgery

BACKGROUND

Postoperative pulmonary complication (PPC) is a leading cause of mortality and poor outcomes in postoperative patients. No studies have enrolled intensive care unit (ICU) patients after noncardiac thoracic surgery, and effective prediction models for PPC have not been developed. This study aimed to explore the incidence and risk factors and construct prediction models for PPC in these patients.

METHODS

This study retrospectively recruited patients admitted to the ICU after noncardiac thoracic surgery at West China Hospital, Sichuan University, from July 2019 to December 2022. The patients were randomly divided into a development cohort and a validation cohort at a 70% versus 30% ratio. The preoperative, intraoperative and postoperative variables during the ICU stay were compared. Univariate and multivariate logistic regression analyses were applied to identify candidate predictors, establish prediction models, and compare the accuracy of the models with that of reported risk models.

RESULTS

A total of 475 ICU patients were enrolled after noncardiac thoracic surgery (median age, 58; 72% male). At least one PPC occurred in 171 patients (36.0%), and the most common PPC was pneumonia (153/475, 32.21%). PPC significantly increased the duration of mechanical ventilation (p < 0.001), length of ICU stay (p < 0.001), length of hospital stay (LOS) (p < 0.001), and rate of reintubation (p = 0.047) in ICU patients. Seven risk factors were identified, and then the prediction nomograms for PPC were constructed. At ICU admission, the area under the curve (AUC) was 0.766, with a sensitivity of 0.71 and specificity of 0.60; after extubation, the AUC was 0.841, with a sensitivity of 0.75 and specificity of 0.83. The models showed robust discrimination in both the development cohort and the validation cohort, and they were well calibrated and more accurate than reported risk models.

CONCLUSIONS

ICU patients who underwent noncardiac thoracic surgery were at high risk of developing PPCs. Prediction nomograms were constructed and they were more accurate than reported risk models, with excellent sensitivity and specificity. Moreover, these findings could help assess individual PPC risk and enhance postoperative management of patients.

Identifying Early Risk Factors for Postoperative Pulmonary Complications in Cardiac Surgery Patients

Background and Objectives: Postoperative pulmonary complications (PPCs) are common in patients who undergo cardiac surgery and are widely acknowledged as significant contributors to increased morbidity, mortality rates, prolonged hospital stays, and healthcare costs. Clinical manifestations of PPCs can vary from mild to severe symptoms, with different radiological findings and varying incidence. Detecting early signs and identifying influencing factors of PPCs is essential to prevent patients from further complications. Our study aimed to determine the frequency, types, and risk factors significant for each PPC on the first postoperative day. The main goal of this study was to identify the incidence of pleural effusion (right-sided, left-sided, or bilateral), atelectasis, pulmonary edema, and pneumothorax as well as detect specific factors related to its development. Materials and Methods: This study was a retrospective single-center trial. It involved 314 adult patients scheduled for elective open-heart surgery under CPB. Results: Of the 314 patients reviewed, 42% developed PPCs within 12 h post-surgery. Up to 60.6% experienced one PPC, while 35.6% developed two PPCs. Pleural effusion was the most frequently observed complication in 89 patients. Left-sided effusion was the most common, presenting in 45 cases. Regression analysis showed a significant association between left-sided pleural effusion development and moderate hypoalbuminemia. Valve surgery was associated with reduced risk for left-sided effusion. Independent parameters for bilateral effusion include increased urine output and longer ICU stays. Higher BMI was inversely related to the risk of pulmonary edema. Conclusions: At least one PPC developed in almost half of the patients. Left-sided pleural effusion was the most common PPC, with hypoalbuminemia as a risk factor for effusion development. Atelectasis was the second most common. Bilateral effusion was the third most common PPC, significantly related to increased urine output. BMI was an independent risk factor for pulmonary edema development.

Prediction modeling of postoperative pulmonary complications following lung resection based on random forest algorithm

Postoperative pulmonary complications (PPCs) are a significant concern following lung resection due to prolonged hospital stays and increased morbidity and mortality among patients. This study aims to develop and validate a risk prediction model for PPCs after lung resection using the random forest (RF) algorithm to enhance early detection and intervention. Data from 180 patients who underwent lung resections at the Third Affiliated Hospital of the Naval Medical University between September 2022 and February 2024 were retrospectively analyzed. The patients were randomly allocated into a training set and a test set in an 8:2 ratio. An RF model was constructed using Python, with feature importance ranked based on the mean Gini index. The predictive performance of the model was evaluated through analyses of the receiver operating characteristic curve, calibration curve, and decision curve. Among the 180 patients included, 47 (26.1%) developed PPCs. The top 5 predictive factors identified by the RF model were blood loss, maximal length of resection, number of lymph nodes removed, forced expiratory volume in the first second as a percentage of predicted value, and age. The receiver operating characteristic curve and calibration curve analyses demonstrated favorable discrimination and calibration capabilities of the model, while decision curve analysis indicated its clinical applicability. The RF algorithm is effective in predicting PPCs following lung resection and holds promise for clinical application.

Comparison of adult versus elderly patients with abdominal trauma: A retrospective database analysis

BACKGROUND

The growing geriatric population has specific medical characteristics that should be taken into account especially in trauma setting. There is little evidence on management of abdominal trauma in the elderly and this article compares the management and outcomes of younger and older patients in order to highlight fields of improvement.

METHOD

We conducted a retrospective database analysis from two European university hospitals selecting patients admitted for abdominal injury and extracted the following data: epidemiological data, mechanisms of the trauma, vital signs, blood tests, injuries, applied treatments, trauma scores and outcomes. We compared to different age group (16-64 and 65+ years old) using uni- and multivariable analysis.

RESULTS

1181 patients were included for statistical analysis. The main mechanisms of injury in both group were traffic accidents and in the elderly group, falls were more frequent. Both had similar Abbreviated Injury Score except for the thoracic injuries, which was higher in the elderly group. We reported a death rate of 13% in the elderly group and 7% in the younger group. However, multivariable analysis did not report age as an independent predictor of mortality. The management including surgery, blood transfusion and need for intensive care were similar in both groups.

CONCLUSION

Although elderly patients suffering abdominal trauma have an almost two fold higher mortality, their management is quite similar leading to an important point of improvement in regards to triage and lower threshold for more aggressive management and surveillance. Age itself does not seem to be a reliable predictor of mortality. Introducing a frailty score when taking care of elderly trauma patients could improve the outcomes.

Albumin Leakage Level during Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Is Associated with Major Complications

The clinical consequences of perioperative albumin extravasation accompanying major abdominal surgery remain underexplored. We retrospectively reviewed the data of patients who underwent cytoreductive surgery (CRS) and hyperthermic intraoperative peritoneal chemotherapy (HIPEC). Parameters of albumin kinetics, including serum albumin concentration decrease (∆Alb) and extravasated albumin level (Albshift), were assessed from surgery until postoperative day (POD) 3. Logistic regression analysis identified factors associated with major complications. The association of albumin kinetics with major complications was evaluated using receiver operating characteristic (ROC) curve analysis. Serum albumin levels decreased during surgery and subsequently increased. Of the 121 analyzed patients, 25 (21%) developed major complications. The ∆Alb and Albshift during surgery and on POD 3 were greater in patients who developed major complications than in those who did not (12 ± 12 vs. 6 ± 14, p = 0.032, and 127.5 (71.9) vs. 48.5 (44.9), p < 0.001, respectively). Perioperative ∆Alb and Albshift were associated with major complications. The areas under the ROC curve of Albshift during the 3 days post-surgery and Albshift on POD 3 were 0.843 and 0.910, respectively. Albshift during the 3 days post-surgery and Albshift on POD 3 were correlated with complications (p < 0.05). In conclusion, perioperative albumin loss was associated with major complications in patients undergoing CRS and HIPEC. Albshift was associated with serious complications.

Predicting lymph node metastasis using preoperative parameters in patients with T1 ampulla of vater cancer

BACKGROUND

Lymph node (LN) metastasis is an established prognostic factor for patients with surgically resected ampulla of Vater (AoV) cancer. The standard procedure for radical resection, including removal of regional LNs, is pancreaticoduodenectomy (PD); however, local excision has been considered as an alternative option for patients in the early stage cancer with significant comorbidities. In the present study, we elucidated the preoperative factors associated with LN metastasis to determine the appropriate surgical extent for T1 AoV cancer.

METHODS

We included patients who underwent surgery for T1 AoV cancer at Samsung Medical Center and Severance Hospital between 2000 and 2019. Risk factors were analyzed to identify the preoperative parameters associated with LN metastasis or regional LN recurrence during follow-up. Finally, using the identified risk factors, a prediction model was constructed.

RESULTS

Among 342 patients, 311 patients underwent PD, whereas 31 patients underwent transduodenal ampullectomy. Fourty-eight patients had LN metastasis according to pathology report, and two patients presented with regional LN recurrence. Age, carbohydrate antigen 19 - 9 (CA 19 - 9), and tumor differentiation were identified as factors associated with the increased risk of LN metastasis or regional LN recurrence. The area under the curve of the prediction model with these three factors was 0.728.

CONCLUSION

Our newly developed prediction model using age, CA 19 - 9, and tumor differentiation can help select patients who require PD over local excision. Nevertheless, additional in-depth analysis is warranted to select appropriate surgical extent for patients with presumed T1 AoV cancer.

Preoperative forced expiratory volume in one second and postoperative respiratory outcomes in nonpulmonary and noncardiac surgery: a retrospective cohort study

BACKGROUND

Although the usefulness of pulmonary function tests has been established for lung resection and coronary artery bypass surgeries, the association between preoperative pulmonary function test and postoperative respiratory complications in nonpulmonary and noncardiac surgery is inconclusive. The purpose of this study was to determine the association between preoperative forced expiratory volume in one second (FEV1) on pulmonary function test and the development of postoperative respiratory failure and/or death in patients undergoing major nonpulmonary and noncardiac surgery.

METHODS

Adult patients aged ≥ 18 years and who underwent nonpulmonary and noncardiac surgery with expected moderate to high risk of perioperative complications from June 2012 to March 2019 were included. The primary exposure was preoperative FEV1 measured by pulmonary function test within six months before surgery. The primary outcome was respiratory failure (i.e., invasive positive pressure ventilation for at least 24 h after surgery or reintubation) and/or death within 30 days after surgery. A logistic regression model was used to adjust for the respiratory failure risk index, which is a scoring system that predicts the probability of postoperative respiratory failure based on patient and surgical factors, and to examine the association between preoperative FEV1 and the development of postoperative respiratory failure and/or death.

RESULTS

Respiratory failure and/or death occurred within 30 days after surgery in 52 (0.9%) of 5562 participants. The incidence of respiratory failure and/or death in patients with FEV1 ≥ 80%, 70%- < 80%, 60%- < 70%, and < 60% was 0.9%, 0.6%, 1.7%, and 1.2%, respectively. Multivariable logistic regression analysis showed no significant association between preoperative FEV1 and postoperative respiratory failure and/or death (adjusted odds ratio per 10% decrease in FEV1: 1.01, 95% confidence interval: 0.88-1.17, P = 0.838). Addition of FEV1 information to the respiratory failure risk index did not improve the prediction of respiratory failure and/or death [area under the receiver operating characteristics curve: 0.78 (95% confidence interval: 0.72-0.84) and 0.78 (95% confidence interval: 0.72-0.84), respectively; P = 0.84].

CONCLUSION

We found no association between preoperative FEV1 and postoperative respiratory failure and/or death in patients undergoing major nonpulmonary and noncardiac surgery.

Evaluation of postoperative results after a presurgical optimisation programme

BACKGROUND

Presurgical optimisation programmes decrease the risk of postoperative complications, reduce hospital stays and speed up patient recovery. They usually involve a multidisciplinary team addressing physical, nutritional and psychosocial issues. The objective of this study was to assess the results of implementing a presurgical optimisation programme led by a liaison nurse in patients undergoing major surgery in a primary general hospital.

METHODS

An observational, retrospective, descriptive, cross-sectional, comparative study based on the revision of patients' health records undergoing major surgery between January 2019 and December 2022. Patients entering the presurgical optimisation programme (intervention group) were compared with patients receiving usual medical care (control group). The presurgical optimisation programme consisted of oral nutritional supplementation, physical exercise, strengthening of lung capacity and psychological and emotional support. Frequency (%) of surgery complications and use of healthcare resources (duration of hospitalisation, time spent in the intensive care unit (ICU), and readmission) at day 30 were recorded. Descriptive statistics were applied.

RESULTS

Two hundred eleven patients (58.5% men, mean age: 65.76 years (SD 11.5), 75.2%. non-smokers; mean body mass index (BMI): 28.32 (SD 5.38); mean Nutritional Risk Score (NRS) 3.71 (SD 1.35; oncology diagnosis: 88.6%) were included: 135 in the intervention group, and 76 in the control group. The average duration of the presurgical optimisation programme was 20 days (SD 5). Frequency of postoperative complications was 25% (n = 33) in the intervention group and 52.6% (n = 40) in the control group (p < 0.001) [odds ratio (OR) = 3.4; 95% confidence interval (CI) (1.8; 6.2)]. 14.5% (n = 19) of patients in the intervention group and 34.2% (n = 26) in the control group had remote postoperative complications [OR = 3.1; 95% CI (1.6; 6.2)]. Patients in the intervention group spent fewer days in the hospital [mean 8.34 (SD 6.70) vs 11.63 (SD 10.63)], and there were fewer readmissions at 30 days (7.6% vs 19.7%) compared with the control group.

CONCLUSIONS

A presurgical optimisation programme led by a liaison nurse decreases the rate of immediate and late surgical complications and reduces hospital stays and readmissions in patients undergoing major surgery.

ARISCAT and LAS VEGAS risk scores for predicting postoperative pulmonary complications after cardiac surgery: a cohort study

Background

Postoperative pulmonary complications (PPCs) could lead to morbidity, mortality, and prolonged hospital stay. Different risk-scoring systems are used to predict the identification of patients at risk of developing PPCs. The diagnostic accuracies of the Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) and Local Assessment of Ventilatory Management During General Anaesthesia for Surgery (LAS VEGAS) risk scores are compared in prediction of PPCs taking pulmonary complication as the gold standard in cardiac surgery.

Materials and methods

A prospective cohort study with consecutive sampling technique. A total of 181 patients were included. Quantitative data is presented as simple descriptive statistics giving mean and standard deviation, and qualitative variables are presented as frequency and percentages. Sensitivity, specificity, positive and negative predictive values, and diagnostic accuracies are also calculated.

Results

Total 181 post-cardiac surgery patients were analyzed. The median [interquartile range] of age, height, weight, and BMI were 60.0 [52.0-67.0] years, 163.0 [156.0-168.0] cm, 71.0 [65.0-80.0] kg and 27.3 [24.2-30.4] kg/m2. 127 (70.2%) were male, and 54 (29.8%) were female. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of ARISCAT for the prediction of PPCs were (94.9%, 4.65%, 76.1%, 22.9% and 73.4%), whereas LAS VEGAS were (97.1%, 4.65%, 76.5%, 33.3% and 75.1%), respectively.

Conclusion

Both the ARISCAT and LAS VEGAS risk scores are of limited value in cardiac surgery patients for the prediction of postoperative pulmonary complications, based on the predicted scores in this study.

Introduction to the novel model of preoperative Multi - Domain Risk Stratification (pMDRS)

Preoperative risk stratification is an important step in surgical procedures. The current scoring systems do not predict accurate overall surgical outcomes in complex comorbid patients. The novel model of preoperative multi-domain risk stratification is described in this article, which categorises patients in to three risk groups, aiming to modify the risk for optimal surgical outcomes.

A prognostic model for use before elective surgery to estimate the risk of postoperative pulmonary complications (GSU-Pulmonary Score): a development and validation study in three international cohorts

BACKGROUND

Pulmonary complications are the most common cause of death after surgery. This study aimed to derive and externally validate a novel prognostic model that can be used before elective surgery to estimate the risk of postoperative pulmonary complications and to support resource allocation and prioritisation during pandemic recovery.

METHODS

Data from an international, prospective cohort study were used to develop a novel prognostic risk model for pulmonary complications after elective surgery in adult patients (aged ≥18 years) across all operation and disease types. The primary outcome measure was postoperative pulmonary complications at 30 days after surgery, which was a composite of pneumonia, acute respiratory distress syndrome, and unexpected mechanical ventilation. Model development with candidate predictor variables was done in the GlobalSurg-CovidSurg Week dataset (global; October, 2020). Two structured machine learning techniques were explored (XGBoost and the least absolute shrinkage and selection operator [LASSO]), and the model with the best performance (GSU-Pulmonary Score) underwent internal validation using bootstrap resampling. The discrimination and calibration of the score were externally validated in two further prospective cohorts: CovidSurg-Cancer (worldwide; February to August, 2020, during the COVID-19 pandemic) and RECON (UK and Australasia; January to October, 2019, before the COVID-19 pandemic). The model was deployed as an online web application. The GlobalSurg-CovidSurg Week and CovidSurg-Cancer studies were registered with ClinicalTrials.gov, NCT04509986 and NCT04384926.

FINDINGS

Prognostic models were developed from 13 candidate predictor variables in data from 86 231 patients (1158 hospitals in 114 countries). External validation included 30 492 patients from CovidSurg-Cancer (726 hospitals in 75 countries) and 6789 from RECON (150 hospitals in three countries). The overall rates of pulmonary complications were 2·0% in derivation data, and 3·9% (CovidSurg-Cancer) and 4·7% (RECON) in the validation datasets. Penalised regression using LASSO had similar discrimination to XGBoost (area under the receiver operating curve [AUROC] 0·786, 95% CI 0·774-0·798 vs 0·785, 0·772-0·797), was more explainable, and required fewer covariables. The final GSU-Pulmonary Score included ten predictor variables and showed good discrimination and calibration upon internal validation (AUROC 0·773, 95% CI 0·751-0·795; Brier score 0·020, calibration in the large [CITL] 0·034, slope 0·954). The model performance was acceptable on external validation in CovidSurg-Cancer (AUROC 0·746, 95% CI 0·733-0·760; Brier score 0·036, CITL 0·109, slope 1·056), but with some miscalibration in RECON data (AUROC 0·716, 95% CI 0·689-0·744; Brier score 0·045, CITL 1·040, slope 1·009).

INTERPRETATION

This novel prognostic risk score uses simple predictor variables available at the time of a decision for elective surgery that can accurately stratify patients' risk of postoperative pulmonary complications, including during SARS-CoV-2 outbreaks. It could inform surgical consent, resource allocation, and hospital-level prioritisation as elective surgery is upscaled to address global backlogs.

FUNDING

National Institute for Health Research.

Combining Spirometry and the ARISCAT Respiratory Risk Assessment Can Improve Postoperative Outcomes and Reduce Mortality Risk in Mexico

Introduction

Although a major goal of preoperative evaluation is to identify risk factors and improve postoperative outcomes, current clinical guidelines in Mexico indicate that preoperative spirometry should only be performed on patients with pulmonary disease. The aim of this study was to compare the incidence of postoperative complications (POC), mortality, and risk factors among adults who did or did not undergo preoperative spirometry, based on their Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) risk level.

Material and methods

An observational, retrospective and comparative study design was used to identify 2059 patients from the General Hospital of Mexico who had an ARISCAT assessment during 2013-2017. Patients were classified in two groups: ARISCAT with spirometry (n = 1306) and ARISCAT without spirometry (n = 753). Chi-square, Fisher's exact test and the Student's t-tests were used to compare groups. Logistic regression was used to identify factors associated with an increased risk of POC and mortality.

Results

In the ARISCAT with spirometry group, 11% of patients had POC, compared with 48% of patients in the ARISCAT without spirometry group. High-risk ARISCAT patients who did not receive spirometry had higher mortality (18%), than those who underwent spirometry (0.4%). Logistic regression results indicate that not performing preoperative spirometry increases the probability of POC and mortality.

Conclusions

Our findings suggest that the combined use of preoperative spirometry and ARISCAT is associated with reduced POC and mortality. Future clinical guidelines should recommend the use of preoperative spirometry for patients with a moderate or high ARISCAT level in Mexico.

Association between reversal agents (sugammadex vs. neostigmine) for neuromuscular block and postoperative pulmonary complications: A retrospective analysis

AIMS

Residual neuromuscular blockade has been linked to pulmonary complications in the postoperative period. This study aimed to determine whether sugammadex was associated with a lower risk of postoperative pulmonary complications (PPCs) compared with neostigmine.

METHODS

This retrospective cohort study was conducted in a tertiary academic medical center. Patients ≥18 year of age undergoing noncardiac surgical procedures with general anesthesia and mechanical ventilation were enrolled between January 2019 and September 2021. We identified all patients receiving rocuronium and reversal with neostigmine or sugammadex via electronic medical record review. The primary endpoint was a composite of PPCs (including pneumonia, atelectasis, respiratory failure, pulmonary embolism, pleural effusion, or pneumothorax). The incidence of PPCs was compared using propensity score analysis.

RESULTS

A total of 1786 patients were included in this study. Among these patients, 976 (54.6%) received neostigmine, and 810 (45.4%) received sugammadex. In the whole sample, PPCs occurred in 81 (4.54%) subjects (7.04% sugammadex vs. 2.46% neostigmine). Baseline covariates were well balanced between groups after overlap weighting. Patients in the sugammadex group had similar risk (overlap weighting OR: 0.75; 95% CI: 0.40 to 1.41) compared to neostigmine. The sensitivity analysis showed consistent results. In subgroup analysis, the interaction P-value for the reversal agents stratified by surgery duration was 0.011.

CONCLUSION

There was no significant difference in the rate of PPCs when the neuromuscular blockade was reversed with sugammadex compared to neostigmine. Patients undergoing prolonged surgery may benefit from sugammadex, which needs to be further investigated.

Exploring phenotype-based ventilator parameter optimization to mitigate postoperative pulmonary complications: a retrospective observational cohort study

PURPOSE

To identify tidal volume (VT) and positive end-expiratory pressure (PEEP) associated with the lowest incidence and severity of postoperative pulmonary complications (PPCs) for each phenotype based on preoperative characteristics.

METHODS

The subjects of this retrospective observational cohort study were 34,910 adults who underwent surgery, using general anesthesia with mechanical ventilation. Initially, the least absolute shrinkage and selection operator regression was employed to select relevant preoperative characteristics. Then, the classification and regression tree (CART) was built to identify phenotypes. Finally, we computed the area under the receiver operating characteristic curves from logistic regressions to identify VT and PEEP associated with the lowest incidence and severity of PPCs for each phenotype.

RESULTS

CARTs classified seven phenotypes for each outcome. A probability of the development of PPCs ranged from the lowest (3.51%) to the highest (68.57%), whereas the probability of the development of the highest level of PPC severity ranged from 3.3% to 91.0%. Across all phenotypes, the VT and PEEP associated with the most desirable outcomes were within a small range of VT 7-8 ml/kg predicted body weight with PEEP of between 6 and 8 cmH2O.

CONCLUSIONS

The ranges of optimal VT and PEEP were small, regardless of the phenotypes, which had a wide range of risk profiles.

Defining the association between the prolonged operative time and 90-day complications in patients undergoing radical cystectomy

Objective

Radical cystectomy is a complex lengthy procedure associated with postoperative morbidity. We aimed to assess the operative time (OT) in patients undergoing radical cystectomy and its impact on 90-day postoperative complications and readmission rates.

Methods

The retrospective cohort study included 296 patients undergoing radical cystectomy and urinary diversion from May 2010 to December 2018 in our institution. The OT of 369 min was set as a cutoff value between short and long OT groups. The primary outcome was 90-day postoperative complication rates. Secondary outcomes were gastrointestinal recovery time, length of hospital stay, and 90-day readmission rates.

Results

The overall incidence of 90-day postoperative complications was 79.7% where 43.2% representing low-grade complications according to the Clavien-Dindo classification (Grade 1 and Grade 2), and 36.5% representing high-grade complications (Grade≥3). Gastrointestinal tract and infectious complications are the most common complications in our data set (45.9% and 45.6%, respectively). On multivariable analysis, prolonged OT was significantly associated with odds of high-grade complications (odds ratio 2.340, 95% confidence interval 1.288-4.250, p=0.005). After propensity score-matched analysis, a higher incidence of major complications was identified in the long OT group 55 (51.4%) compared to 35 (32.7%) in the short OT group (p=0.006). A shorter gastrointestinal tract recovery time was noticed in the short OT group (p=0.009). Prolonged OT was associated with a higher 90-day readmission rate on univariate and multivariate analyses (p<0.001, p=0.001, respectively).

Conclusion

Prolonged OT (>369 min) is associated with an increased risk of postoperative complications and readmission rates. The perception of potential postoperative complications requires careful monitoring of these patients which could translate into better operative outcomes.

A comparative study of surgical outcomes for secondary spontaneous pneumothorax and the postoperative survival prognostic factor: interstitial vs. non-interstitial pneumonia

PURPOSE

To investigate the surgical outcomes and postoperative survival prognostic factors of intractable secondary spontaneous pneumothorax.

METHODS

A total of 95 patients who underwent thoracoscopic surgery for intractable secondary spontaneous pneumothorax between April 2010 and March 2020 were included in this study. These patients were classified into interstitial pneumonia and non-interstitial pneumonia groups, and a comparative study was performed on surgical outcomes and postoperative survival prognostic factors.

RESULTS

There was no difference in the 1-year overall survival rate between the two groups. However, the 3-year overall survival rate was significantly lower in the interstitial pneumonia group than in the non-interstitial pneumonia group. The differences in short-term surgical outcomes (persistent air leakage, postoperative complications, etc.) were not significant between the two groups. Univariate analysis revealed that the drainage period, the development of postoperative complications, and recurrence were significant independent postoperative survival prognostic factors for all cases. Postoperative complications were the only associated postoperative survival prognostic factor for interstitial pneumonia pneumothorax in the multivariate analysis.

CONCLUSION

The development of postoperative complications can cause poor postoperative survival prognosis of intractable secondary spontaneous pneumothorax due to interstitial pneumonia.

Major liver resections, perioperative issues and posthepatectomy liver failure: A comprehensive update for the anesthesiologist

Significant advances in surgical techniques and relevant medium- and long-term outcomes over the past two decades have led to a substantial expansion in the indications for major liver resections. To support these outstanding results and to reduce perioperative complications, anesthesiologists must address and master key perioperative issues (preoperative assessment, proactive intraoperative anesthesia strategies, and implementation of the Enhanced Recovery After Surgery approach). Intensive care unit monitoring immediately following liver surgery remains a subject of active and often unresolved debate. Among postoperative complications, posthepatectomy liver failure (PHLF) occurs in different grades of severity (A-C) and frequency (9%-30%), and it is the main cause of 90-d postoperative mortality. PHLF, recently redefined with pragmatic clinical criteria and perioperative scores, can be predicted, prevented, or anticipated. This review highlights: (1) The systemic consequences of surgical manipulations anesthesiologists must respond to or prevent, to positively impact PHLF (a proactive approach); and (2) the maximal intensive treatment of PHLF, including artificial options, mainly based, so far, on Acute Liver Failure treatment(s), to buy time waiting for the recovery of the native liver or, when appropriate and in very selected cases, toward liver transplant. Such a clinical context requires a strong commitment to surgeons, anesthesiologists, and intensivists to work together, for a fruitful collaboration in a mandatory clinical continuum.

Semirecumbent Positioning During Anesthesia Recovery and Postoperative Hypoxemia: A Randomized Clinical Trial

Importance

The efficacy of a semirecumbent position (SRP) in reducing postoperative hypoxemia during anesthesia emergence is unclear despite its widespread use.

Objective

To determine the differences in postoperative hypoxemia between patients in an SRP and a supine position.

Design, Setting, and Participants

This randomized clinical trial was performed at a tertiary hospital in China between March 20, 2021, and May 10, 2022. Patients scheduled to undergo laparoscopic upper abdominal surgery under general anesthesia were enrolled. Study recruitment and follow-up are complete.

Interventions

Patients were randomized to 1 of the following positions at the end of the operation until leaving the postanesthesia care unit: supine (group S), 15° SRP (group F), or 30° SRP (group T).

Main Outcomes and Measures

The primary outcome was the incidence of postoperative hypoxemia in the postanesthesia care unit. Severe hypoxemia was also evaluated.

Results

Out of 700 patients (364 men [52.0%]; mean [SD] age, 47.8 [11.3] years), 233 were randomized to group S (126 men [54.1%]; mean [SD] age, 48.2 [10.9] years), 233 to group F (122 men [52.4%]; mean [SD] age, 48.1 [10.9] years), and 234 to group T (118 women [50.4%]; mean [SD] age, 47.2 [12.1] years). Postoperative hypoxemia differed significantly among the 3 groups (group S, 109 of 233 [46.8%]; group F, 105 of 233 [45.1%]; group T, 76 of 234 [32.5%]; P = .002). This difference was statistically significant for groups T vs S (risk ratio [RR], 0.69 [95% CI, 0.55-0.87]; P = .002) and groups T vs F (RR, 0.72 [95% CI, 0.57-0.91]; P = .007), but not for groups F vs S (RR, 0.96 [95% CI, 0.79-1.17]; P = .78). Severe hypoxemia also differed among the 3 groups (group S, 61 of 233 [26.2%]; group F, 53 of 233 [22.7%]; group T, 36 of 234 [15.4%]; P = .01). This difference was statistically significant for groups T vs S (RR, 0.59 [95% CI, 0.41-0.85]; P = .005).

Conclusions and Relevance

In this randomized clinical trial of SRP during anesthesia recovery in patients undergoing laparoscopic upper abdominal surgery, postoperative hypoxemia was significantly reduced in group T compared with group F or group S.

Trial Registration

Chinese Clinical Trial Registry Identifier: ChiCTR2100045087.

Rationale and study design for an Individualized PeriopeRative Open lung VEntilatory approach in Emergency Abdominal Laparotomy/scopy: study protocol for a prospective international randomized controlled trial

BACKGROUND

Postoperative pulmonary complications (PPC) are the most frequent postoperative complications, with an estimated prevalence in elective surgery ranging from 20% in observational cohort studies to 40% in randomized clinical trials. However, the prevalence of PPCs in patients undergoing emergency abdominal surgery is not well defined. Lung-protective ventilation aims to minimize ventilator-induced lung injury and reduce PPCs. The open lung approach (OLA), which combines recruitment manoeuvres (RM) and positive end-expiratory pressure (PEEP) titration, aims to minimize areas of atelectasis and the development of PPCs; however, there is no conclusive evidence in the literature that OLA can prevent PPCs. The purpose of this study is to compare an individualized perioperative OLA with conventional standardized lung-protective ventilation in patients undergoing emergency abdominal surgery with clinical signs of intraoperative lung collapse.

METHODS

Randomized international clinical trial to compare an individualized perioperative OLA (RM plus individualized PEEP and individualized postoperative respiratory support) with conventional lung-protective ventilation (standard PEEP of 5 cmH2O and conventional postoperative oxygen therapy) in patients undergoing emergency abdominal surgery with clinical signs of lung collapse. Patients will be randomised to open-label parallel groups. The primary outcome is any severe PPC during the first 7 postoperative days, including: acute respiratory failure, pneumothorax, weaning failure, acute respiratory distress syndrome, and pulmonary infection. The estimated sample size is 732 patients (366 per group). The final sample size will be readjusted during the interim analysis.

DISCUSSION

The Individualized Perioperative Open-lung Ventilatory Strategy in emergency abdominal laparotomy (iPROVE-EAL) is the first multicentre, randomized, controlled trial to investigate whether an individualized perioperative approach prevents PPCs in patients undergoing emergency surgery.