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

Positive end-expiratory pressure and postoperative complications in patients with obesity: a review and meta-analysis

OBJECTIVE

In patients with obesity, use of positive end-expiratory pressure (PEEP) > 5 cm H₂ O (centimeters of water) has been shown to prevent intraoperative atelectasis. This study compares the rate of postoperative pulmonary complications (PPCs) associated with PEEP > 5 cm H₂ O and PEEP ≤ 5 cm H₂ O in patients with obesity who underwent surgery under general anesthesia with mechanical ventilation.

METHODS

This study searched Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) using the terms "PEEP," "anesthesia," and "ventilation." Cochrane ReviewManager (RevMan) version 5 was used for data analysis. The primary outcome was a composite of PPCs, including atelectasis, pneumonia, pneumothorax, and acute respiratory failure.

RESULTS

The initial search identified 903 titles and abstracts, and 4 randomized controlled trials were included for analysis. We included a total of 2116 participants from four randomized controlled trials that compared PEEP ≤ 5 cm H₂ O with PEEP > 5 cm H₂ O in adult patients with obesity. There was no statistically significant difference in PPCs between the PEEP ≤ 5 cm H₂ O and PEEP > 5 cm H₂ O groups (risk ratio = 2.21, 95% CI: 0.41-11.83; p = 0.35). However, a significant heterogeneity was found within included studies (I²  = 53%).

CONCLUSIONS

It is unclear whether PEEP > 5 cm H₂ O improves the postoperative clinical outcome in patients with obesity, which is in contrast to previously established evidence that it reduces atelectasis in patients with obesity.

Postoperative Pulmonary Complications in the ENIGMA II Trial: A Post Hoc Analysis

BACKGROUND

Nitrous oxide promotes absorption atelectasis in poorly ventilated lung segments at high inspired concentrations. The Evaluation of Nitrous oxide In the Gas Mixture for Anesthesia (ENIGMA) trial found a higher incidence of postoperative pulmonary complications and wound sepsis with nitrous oxide anesthesia in major surgery compared to a fraction of inspired oxygen of 0.8 without nitrous oxide. The larger ENIGMA II trial randomized patients to nitrous oxide or air at a fraction of inspired oxygen of 0.3 but found no effect on wound infection or sepsis. However, postoperative pulmonary complications were not measured. In the current study, post hoc data were collected to determine whether atelectasis and pneumonia incidences were higher with nitrous oxide in patients who were recruited to the Australian cohort of ENIGMA II.

METHODS

Digital health records of patients who participated in the trial at 10 Australian hospitals were examined blinded to trial treatment allocation. The primary endpoint was the incidence of atelectasis, defined as lung atelectasis or collapse reported on chest radiology. Pneumonia, as a secondary endpoint, required a diagnostic chest radiology report with fever, leukocytosis, or positive sputum culture. Comparison of the nitrous oxide and nitrous oxide-free groups was done according to intention to treat using chi-square tests.

RESULTS

Data from 2,328 randomized patients were included in the final data set. The two treatment groups were similar in surgical type and duration, risk factors, and perioperative management recorded for ENIGMA II. There was a 19.3% lower incidence of atelectasis with nitrous oxide (171 of 1,169 [14.6%] vs. 210 of 1,159 [18.1%]; odds ratio, 0.77; 95% CI, 0.62 to 0.97; P = 0.023). There was no difference in pneumonia incidence (60 of 1,169 [5.1%] vs. 52 of 1159 [4.5%]; odds ratio, 1.15; 95% CI, 0.77 to 1.72; P = 0.467) or combined pulmonary complications (odds ratio, 0.84; 95% CI, 0.69 to 1.03; P = 0.093).

CONCLUSIONS

In contrast to the earlier ENIGMA trial, nitrous oxide anesthesia in the ENIGMA II trial was associated with a lower incidence of lung atelectasis, but not pneumonia, after major surgery.

EDITOR’S PERSPECTIVE

Right Ventricle Response to Major Lung Resection (the RIVER Study)

BACKGROUNDS

Major lung resection is associated with high postoperative morbidity and mortality, especially due to cardiorespiratory complications. Right ventricle (RV) ejection, pulmonary artery (PA) pressure, and tone are tightly coupled. Since the RV is exquisitely sensitive to changes in afterload, an acute increase in RV outflow resistance (i.e., acute pulmonary embolism [PE]) will cause acute RV dilatation and, a reduction of left ventricle compliance too, rapidly spiraling to acute cardiogenic shock and death. We investigated the changing in RV performance after major lung resection.

MATERIALS AND METHODS

We carried out transthoracic echocardiography (TTE) aiming at searching for the incidence of early RV systolic dysfunction (defined as tricuspid annulus plane systolic excursion [TAPSE] <17 cm, S'-tissue Doppler imaging <10 cm/s) and estimate the RV-PA coupling by the TAPSE/pulmonary artery pressures (PAPs) ratio after major lung resection. The TTE has been performed before and immediately after surgery.

RESULTS

After the end of the operation the echocardiographic parameters of the RV function worsened. TAPSE decreased from 24 (21 ÷ 28) to 18 (16 ÷ 22) mm (P = 0.015) and PAPs increased from 26 (25 ÷ 30) to 30 (25 ÷ 39) mmHg (P = 0.013). TAPSE/PAPs ratio decreased from 0.85 (0.80 ÷ 0.90) to 0.64 (0.54 ÷ 0.79) mm/mmHg (P = 0.002).

CONCLUSIONS

In line with previous reports, after major lung resection the increase in afterload reduces the RV function, but the impairment remains clinically not relevant. The different clinical picture of an acute cor pulmonale due to PE implies that the pathogenesis of cardiac failure involves more pathways than the mere mechanic occlusion of the blood flow.

Emergency use of sugammadex after failure of standard reversal drugs and postoperative pulmonary complications: A retrospective cohort study

Background and Aims

The use of sugammadex instead of neostigmine for the reversal of neuromuscular blockade may decrease postoperative pulmonary complications. It is unclear if this finding is applicable to situations where sugammadex is administered after the administration of neostigmine. The objective of this study was to compare the incidence of a composite outcome measure of major postoperative pulmonary complications in patients who received sugammadex as a rescue agent after neostigmine versus those who received sugammadex alone for reversal of neuromuscular blockade.

Material and Methods

This retrospective cohort study analyzed the medical records of adult patients who underwent elective inpatient noncardiac surgery under general anesthesia and received sugammadex for reversal of neuromuscular blockade, at a tertiary care academic hospital between August 2016 and November 2018.

Results

A total of 1,672 patients were included, of whom 1,452 underwent reversal with sugammadex alone and 220 received sugammadex following reversal with neostigmine/glycopyrrolate. The composite primary outcome was diagnosed in 60 (3.6%) patients. Comparing these two groups, and after adjusting for confounding factors, patients who received sugammadex after reversal with neostigmine had more postoperative pulmonary complications than those reversed with sugammadex alone (6.8% vs. 3.1%, odds ratio, 2.29; 95% confidence interval [CI], 1.25 to 4.18; P = 0.006).

Conclusion

The use of sugammadex following reversal with neostigmine was associated with a higher incidence of postoperative pulmonary complications as compared to the use of sugammadex alone. The implications of using sugammadex after the failure of standard reversal drugs should be investigated in prospective studies.

Risk factors for achieving textbook outcome after laparoscopic duodenum-preserving total pancreatic head resection: a retrospective cohort study

INTRODUCTION

The risk factors for achieving textbook outcome (TO) after laparoscopic duodenum-preserving total pancreatic head resection (LDPPHR-t) are unknown, and no relevant articles have been reported so far. The aim of this study was to identify the risk factors for achieving TO after LDPPHR-t.

METHODS

The risk factors for achieving TO after LDPPHR-t were retrospectively evaluated by logistic regression analysis in 31 consecutive patients from May 2020 to December 2021.

RESULTS

All LDPPHR-t procedures were successfully performed without conversion. There was no death within 90 days after surgery and no readmission within 30 days after discharge. The percentage of achieving TO after LDPPHR-t was 61.3% (19/31). Among the six TO items, the postoperative complication of grade B/C postoperative pancreatic fistula (POPF) occurred most frequently with 22.6%, followed by grade B/C bile leakage with 19.4%, Clavien-Dindo≥III complications with 19.4%, and grade B/C postpancreatectomy hemorrhage with 16.1%. POPF was the major obstacle to achieve TO after LDPPHR-t. Placing an endoscopic nasobiliary drainage (ENBD) catheter and prolonged operation time (>311 min) were significantly associated with the decreased probability of achieving TO after LDPPHR-t (odd ratio (OR), 25.775; P =0.012 and OR, 16.378; P =0.020, respectively). Placing an ENBD catheter was the only significant independent risk factor for POPF after LDPPHR-t (OR, 19.580; P =0.017). Bile leakage was the independent risk factor for postpancreatectomy hemorrhage after LDPPHR-t (OR, 15.754; P =0.040). The prolonged operation time was significantly correlated with Clavien-Dindo grade≥III complications after LDPPHR-t (OR, 19.126; P =0.024).

CONCLUSION

Placing the ENBD catheter was the independent risk factor for POPF and achieving TO after LDPPHR-t. In order to reduce POPF and increase the probability of achieving TO, placing an ENBD catheter should be avoided prior to LDPPHR-t.

Is atelectasis related to the development of postoperative pneumonia? a retrospective single center study

BACKGROUND

Atelectasis may play a substantial role in the development of pneumonia. However, pneumonia has never been evaluated as an outcome of atelectasis in surgical patients. We aimed to determine whether atelectasis is related to an increased risk of postoperative pneumonia, intensive care unit (ICU) admission and hospital length of stay (LOS).

METHODS

The electronic medical records of adult patients who underwent elective non-cardiothoracic surgery under general anesthesia between October 2019 and August 2020 were reviewed. They were divided into two groups: one who developed postoperative atelectasis (atelectasis group) and the other who did not (non-atelectasis group). The primary outcome was the incidence of pneumonia within 30 days after the surgery. The secondary outcomes were ICU admission rate and postoperative LOS.

RESULTS

Patients in the atelectasis group were more likely to have risk factors for postoperative pneumonia including age, body mass index, a history of hypertension or diabetes mellitus and duration of surgery, compared with those in the non-atelectasis. Among 1,941 patients, 63 (3.2%) developed postoperative pneumonia; 5.1% in the atelectasis group and 2.8% in the non-atelectasis (P = 0.025). In multivariable analysis, atelectasis was associated with an increased risk of pneumonia (adjusted odds ratio, 2.33; 95% CI: 1.24 - 4.38; P = 0.008). Median postoperative LOS was significantly longer in the atelectasis group (7 [interquartile range: 5-10 days]) than in the non-atelectasis (6 [3-8] days) (P < 0.001). Adjusted median duration was also 2.19 days longer in the atelectasis group (β, 2.19; 95% CI: 0.821 - 2.834; P < 0.001). ICU admission rate was higher in the atelectasis group (12.1% vs. 6.5%; P < 0.001), but it did not differ between the groups after adjustment for confounders (adjusted odds ratio, 1.52; 95% CI: 0.88 - 2.62; P = 0.134).

CONCLUSION

Among patients undergoing elective non-cardiothoracic surgery, patients with postoperative atelectasis were associated with a 2.33-fold higher incidence of pneumonia and a longer LOS than those without atelectasis. This finding alerts the need for careful management of perioperative atelectasis to prevent or reduce the adverse events including pneumonia and the burden of hospitalizations.

TRIAL REGISTRATION

None.

Retrospective comparison of operative technique for chest wall injuries

BACKGROUND

Surgical management of chest wall injuries is a common procedure. However, operative techniques are diverse, and no universal guidelines exist. There is a lack of studies comparing the outcome with different operative techniques for chest wall surgery. The aim of this study was to compare hospital outcomes between patients operated for chest wall injuries with a conventional method with large incisions and often a thoracotomy or a minimally invasive, muscle sparing method.

PATIENTS AND METHODS

A retrospective study was carried out including patients ≥18 years operated for chest wall injuries 2010-2020. Patients were divided into two groups based on the surgery performed: conventional surgery (C-group) and minimally invasive surgery (M-group). Data on demographics, trauma, surgery, and outcomes were extracted from patient records. Primary outcome was length of stay on mechanical ventilator (MV-LOS). Secondary outcomes were length of stay in intensive care (ICU-LOS) and in hospital (H-LOS), and complications such as re-operation, incidence of empyema, tracheostomy, pneumonia, and mortality.

RESULTS

Of 311 included patients, 220 were in the C-group and 91 in the M-group. The groups were similar in demographics and injury pattern. MV-LOS was 0 (0-65) in the C-group vs 0 (0-34) in the M-group (p < 0.001). ICU-LOS and H-LOS were significantly shorter in the M-group as compared to the C-group (p < 0.001), however with a large overlap. Tracheostomy was performed in 22.3% of patients in the C-group vs 5.4% in the M-group (p < 0.001). Pneumonia was diagnosed in 32.3% of patients in the C-group vs 16.1% in the M-group (p = 0.004). In-hospital mortality was lower in the M-group compared to the C-group but there was no difference in mortality within 30 days or a year.

CONCLUSIONS

Our study indicates that a minimally invasive technique was favorable regarding clinical outcomes for patients operated for chest wall injuries.

Low tidal volume ventilation for patients undergoing laparoscopic surgery: a secondary analysis of a randomised clinical trial

BACKGROUND

We recently reported the results for a large randomized controlled trial of low tidal volume ventilation (LTVV) versus conventional tidal volume (CTVV) during major surgery when positive end expiratory pressure (PEEP) was equal between groups. We found no difference in postoperative pulmonary complications (PPCs) in patients who received LTVV. However, in the subgroup of patients undergoing laparoscopic surgery, LTVV was associated with a numerically lower rate of PPCs after surgery. We aimed to further assess the relationship between LTVV versus CTVV during laparoscopic surgery.

METHODS

We conducted a post-hoc analysis of this pre-specified subgroup. All patients received volume-controlled ventilation with an applied PEEP of 5 cmH₂O and either LTVV (6 mL/kg predicted body weight [PBW]) or CTVV (10 mL/kg PBW). The primary outcome was the incidence of a composite of PPCs within seven days.

RESULTS

Three hundred twenty-eight patients (27.2%) underwent laparoscopic surgeries, with 158 (48.2%) randomised to LTVV. Fifty two of 157 patients (33.1%) assigned to LTVV and 72 of 169 (42.6%) assigned to conventional tidal volume developed PPCs within 7 days (unadjusted absolute difference, - 9.48 [95% CI, - 19.86 to 1.05]; p = 0.076). After adjusting for pre-specified confounders, the LTVV group had a lower incidence of the primary outcome than patients receiving CTVV (adjusted absolute difference, - 10.36 [95% CI, - 20.52 to - 0.20]; p = 0.046).

CONCLUSION

In this post-hoc analysis of a large, randomised trial of LTVV we found that during laparoscopic surgeries, LTVV was associated with a significantly reduced PPCs compared to CTVV when PEEP was applied equally between both groups.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry no: 12614000790640.

Intraoperative Ventilator Management of the Critically Ill Patient

Strategies for the intraoperative ventilator management of the critically ill patient focus on parameters used for lung protective ventilation with acute respiratory distress syndrome, preventing or limiting the deleterious effects of mechanical ventilation, and optimizing anesthetic and surgical conditions to limit postoperative pulmonary complications for patients at risk. Patient conditions such as obesity, sepsis, the need for laparoscopic surgery, or one-lung ventilation may benefit from intraoperative lung protective ventilation strategies. Anesthesiologists can use risk evaluation and prediction tools, monitor advanced physiologic targets, and incorporate new innovative monitoring techniques to develop an individualized approach for patients.

Postoperative Respiratory Failure and Advanced Ventilator Settings

Postoperative respiratory failure has a multifactorial etiology, of which atelectasis is the most common mechanism. Its injurious effects are magnified by surgical inflammation, high driving pressures, and postoperative pain. Chest physiotherapy and noninvasive ventilation are good options to prevent progression of respiratory failure. Acute respiratory disease syndrome is a late and severe finding, which is associated with high morbidity and mortality. If present, proning is a safe, effective, and underutilized therapy. Extracorporeal membrane oxygenation is an option only when traditional supportive measures have failed.

Effect of goal-directed fluid therapy based on plasma colloid osmotic pressure on the postoperative pulmonary complications of older patients undergoing major abdominal surgery

BACKGROUND

As an important component of accelerated rehabilitation surgery, goal-directed fluid therapy (GDT) is one of the optimized fluid therapy strategies and is closely related to perioperative complications and mortality. This article aimed to study the effect of combining plasma colloid osmotic pressure (COP) with stroke volume variation (SVV) as a target for intraoperative GDT for postoperative pulmonary complications in older patients undergoing major abdominal surgery.

METHODS

In this study, older patients (n = 100) undergoing radical resection of gastroenteric tumors were randomized to three groups: Group C (n1 = 31) received a conventional infusion regimen, Group S1 (n2 = 34) received GDT based on SVV, and Group S2 (n3 = 35) received GDT based on SVV and COP. The results were recorded, including the lung injury score (LIS); PaO₂/FiO₂ ratio; lactic acid value at the times of beginning (T0) and 1 h (T1), 2 h (T2), and 3 h (T3) after liquid infusion in the operation room; the total liquid infusion volume; infusion volumes of crystalline and colloidal liquids; urine production rate; pulmonary complications 7 days after surgery; and the severity grading of postoperative pulmonary complications.

RESULTS

The patients in the S2 group had fewer postoperative pulmonary complications than those in the C group (P < 0.05) and the proportion of pulmonary complications of grade 1 and higher than grade 2 in S2 group was significantly lower than that in C group (P <0.05); the patients in the S2 group had a higher PaO₂/FiO₂ ratio than those in the C group (P < 0.05), lower LIS than those in the S1 and C groups (P < 0.05), less total liquid infusion than those in the C group (P < 0.05), and more colloidal fluid infusion than those in the S1 and C groups (P < 0.05).

CONCLUSION

The findings of our study show that intraoperative GDT based on COP and SVV can reduce the incidence of pulmonary complications and conducive to shortening the hospital stay in older patients after gastrointestinal surgery.

TRIAL REGISTRATION

Chinese Clinical Trial. no. ChiCTR2100045671. Registry at www.chictr.org.cn on April 20, 2021.

Protocol for the derivation and external validation of a 30-day postoperative pulmonary complications (PPCs) risk prediction model for elderly patients undergoing thoracic surgery: a cohort study in southern China

INTRODUCTION

Postoperative pulmonary complications (PPCs) occur after up to 60% of non-cardiac thoracic surgery (NCTS), especially for multimorbid elderly patients. Nevertheless, current risk prediction models for PPCs have major limitations regarding derivation and validation, and do not account for the specific risks of NCTS patients. Well-founded and externally validated models specific to elderly NCTS patients are warranted to inform consent and treatment decisions.

METHODS AND ANALYSIS

We will develop, internally and externally validate a multivariable risk model to predict 30-day PPCs in elderly NCTS patients. Our cohort will be generated in three study sites in southern China with a target population of approximately 1400 between October 2021 and December 2023. Candidate predictors have been selected based on published data, clinical expertise and epidemiological knowledge. Our model will be derived using the combination of multivariable logistic regression and bootstrapping technique to lessen predictors. The final model will be internally validated using bootstrapping validation technique and externally validated using data from different study sites. A parsimonious risk score will then be developed on the basis of beta estimates derived from the logistic model. Model performance will be evaluated using area under the receiver operating characteristic curve, max-rescaled Brier score and calibration slope. In exploratory analysis, we will also assess the net benefit of Probability of PPCs Associated with THoracic surgery in elderly patients score in the complete cohort using decision curve analysis.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Institutional Review Board of the Affiliated Cancer Hospital and Institute of Guangzhou Medical University, the Second Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine and the University of Hongkong-Shenzhen Hospital, respectively. The final risk prediction model will be published in an appropriate journal and further disseminated as an online calculator or nomogram for clinical application. Approved and anonymised data will be shared.

TRIAL REGISTRATION NUMBER

ChiCTR2100051170.

Hepatic hydrothorax is not associated with increased complications or poor survival after liver transplantation

BACKGROUND

Hepatic hydrothorax (HH) is associated with a poor prognosis. Liver transplant (LT) is the best treatment modality. We aim to assess post-LT morbidity and mortality in patients with cirrhosis and HH.

RESEARCH DESIGN AND METHODS

Adult patients with cirrhosis, who underwent LT at our institution from 2015 to 2020, were retrospectively reviewed. Baseline data was obtained at the time of LT. Patients were followed from baseline until the last follow-up or death. Censoring occurred at the time of the last follow-up or death, whichever occurred earlier. Cumulative incidence of outcomes was determined by the Kaplan-Meier method. Short-term post-operative complications were compared between both groups as well.

RESULTS

428 patients had a LT, of which 72 (16.8%) had HH. Most of the baseline characteristics were similar between patients with and without HH; however, patients in the HH group had a higher proportion of pre-operative history of ascites and hepatic encephalopathy. Pre-operative HH was not significantly associated with post-LT mortality (Hazard ratio 1.12, 95% confidence interval 0.54-2.32; P-value 0.76). Patients had similar short-term post-operative complications between both groups.

CONCLUSIONS

LT is an excellent therapeutic option for patients with cirrhosis and HH, with excellent long-term survival without increased morbidity.

Non-invasive hemoglobin estimation for preoperative anemia screening

BACKGROUND

Preoperative anemia is common and associated with adverse postoperative outcomes. Assessment of hemoglobin concentrations may facilitate optimization prior to surgery. However, phlebotomy-based hemoglobin measurement may contribute to patient discomfort and iatrogenic blood loss, which makes non-invasive hemoglobin estimation attractive in this setting.

STUDY DESIGN AND METHODS

This is a prospective study of adult patients presenting for preoperative evaluation before elective surgery at a tertiary care medical center. The Masimo Pronto Pulse CO-Oximeter was utilized to estimate blood hemoglobin concentrations (SpHb), which were then compared with hemoglobin concentrations obtained via complete blood count. Receiver operating curves were used to identify SpHb values maximizing specificity for anemia detection while meeting a minimum sensitivity of 80%.

RESULTS

A total of 122 patients were recruited with a median (interquartile range) age of 66 (58, 72) years. SpHb measurements were obtained in 112 patients (92%). SpHb generally overestimated hemoglobin with a mean (± 1.96 × standard deviation) difference of 0.8 (-2.2, 3.9) g/dL. Preoperative anemia, defined by hemoglobin <12.0 g/dL in accordance with institutional protocol, was present in 22 patients (20%). The optimal SpHb cut-point to identify anemia was 13.5 g/dL: sensitivity 86%, specificity 81%, negative predictive value 96%, and positive predictive value 53%. Utilizing this cut-point, 60% (73/122) of patients could have avoided phlebotomy-based hemoglobin assessment, while an anemia diagnosis would have been missed in <3% (3/122).

CONCLUSION

The use of SpHb devices for anemia screening in surgical patients is feasible with the potential to reliably rule-out anemia despite limited accuracy.

Efficacy of maintaining low-tidal volume mechanical ventilation as compared to resting lung strategy during coronary artery bypass graft cardiopulmonary bypass surgery: A post-hoc analysis of the MECANO trial

STUDY OBJECTIVE

To compare a low-tidal-volume with positive end-expiratory pressure strategy (VENT strategy) to a resting-lung-strategy (i.e., no-ventilation (noV) strategy) during cardiopulmonary bypass for coronary artery bypass graft surgery on the incidence of postoperative pulmonary complications.

DESIGN

Post-hoc analysis of the MECANO trial which was a prospective single-center, blind, randomized, parallel-group controlled trial.

SETTING

Tertiary care cardiac surgery center.

PATIENTS

Patients who underwent isolated on-pump coronary bypass surgery were randomized either to VENT or noV group.

INTERVENTION

During the cardiopulmonary bypass phase of the cardiac surgery procedure, mechanical ventilation in the VENT group consisted of a tidal volume of 3 mL/kg, a respiratory rate of 5 per minute and a positive end-expiratory pressure of 5 cmH₂O. Patients in the noV group received no ventilation during this phase.

MEASUREMENTS

Primary composite outcome combining death, early respiratory failure, ventilation support beyond day 2 and reintubation.

MAIN RESULTS

In this post-hoc analysis, we retained 725 patients who underwent isolated CABG surgery, from the 1501 patients included in the original study. There were 352 in the VENT group and 373 patients in the noV group. Post-hoc comparison yielded no differences in baseline characteristics between these two groups. The primary outcome occurred less frequently in the VENT group than in the noV group, with 44 (12.5%) and 76 (20.4%) respectively (odds-ratio (OR) = 0.56 (0.37-0.84), p = 0.004). There were fewer early respiratory dysfunctions and prolonged respiratory support in the VENT group (respectively, OR = 0.34 (0.12-0.96) p = 0.033 and OR = 0.51 (0.27-0.94) p = 0.029). Complications related to mechanical ventilation were similar in the two groups.

CONCLUSIONS

In this post-hoc analysis, maintaining low-tidal ventilation compared to a resting-lung strategy was associated with fewer pulmonary postoperative complications in patients who underwent isolated CABG procedures.

Preoperative decline in skeletal muscle strength of patients with cardiovascular disease affects postoperative pulmonary complication occurrence: a single-center retrospective study

BACKGROUND

Dynapenia, defined as age-related skeletal muscle strength decline, has been reported as a poor prognostic factor in patients with cardiovascular disease. Decline in skeletal muscle strength (DS), the main symptom of dynapenia, may be an important clinical indicator in patients undergoing cardiac surgery. However, the relationship between DS and postoperative pulmonary complication occurrence is unclear. Herein, we investigated the relationship between preoperative DS and postoperative pulmonary complication occurrence in patients undergoing cardiac surgery.

METHODS

We enrolled 125 patients who underwent cardiac surgery. DS was determined by low grip strength and quadriceps isometric strength. The patients were divided into DS and non-DS groups. The relationship between the clinical characteristics and preoperative physical function was compared, and factors associated with postoperative pulmonary complication occurrence were investigated using multivariate logistic regression analysis.

RESULTS

There were 42 (33.6%) patients in the DS group and 83 (66.4%) patients in the non-DS group. Compared with the non-DS group, the DS group was significantly older and had a higher body mass index and Japan SCORE (operative mortality rate and major complication rate). The DS group also had a lower estimated glomerular filtration rate and preoperative Barthel index than the non-DS group. Furthermore the DS group had a significantly higher incidence of postoperative pulmonary complications and length of intensive care unit stay, and their postoperative rehabilitation was prolonged compared to the non-DS group. Multivariate logistic regression analysis revealed that DS was a determinant of postoperative pulmonary complications (odds ratio 4.26, 95% confidence interval 1.63‒11.14).

CONCLUSIONS

We showed that preoperative DS was an independent risk factor for postoperative pulmonary complications in patients undergoing cardiac surgery. Skeletal muscle strength before cardiac surgery may be an important clinical indicator for predicting the prognosis of patients from post-surgery to discharge and for planning postoperative rehabilitation programs.

Comparing the effects of continuous positive airway pressure via mask or helmet interface on oxygenation and pulmonary complications after major abdominal surgery: a randomized trial

The risk of pulmonary complications is high after major abdominal surgery but may be reduced by prophylactic postoperative noninvasive ventilation using continuous positive airway pressure (CPAP). This study compared the effects of intermittent mask CPAP (ICPAP) and continuous helmet CPAP (HCPAP) on oxygenation and the risk of pulmonary complications following major abdominal surgery. Patients undergoing open abdominal aortic aneurysm repair or pancreaticoduodenectomy were randomized (1:1) to either postoperative ICPAP or HCPAP. Oxygenation was evaluated as the partial pressure of oxygen in arterial blood fraction of inspired oxygen ratio (PaO₂/FIO₂) at 6 h, 12 h, and 18 h postoperatively. Pulmonary complications were defined as X-ray verified pneumonia/atelectasis, clinical signs of pneumonia, or supplementary oxygen beyond postoperative day 3. Patient-reported comfort during CPAP treatment was also evaluated. In total, 96 patients (ICPAP, n = 48; HCPAP, n = 48) were included, and the type of surgical procedure were evenly distributed between the groups. Oxygenation did not differ between the groups by 6 h, 12 h, or 18 h postoperatively (p = 0.1, 0.08, and 0.67, respectively). Nor was there any difference in X-ray verified pneumonia/atelectasis (p = 0.40) or supplementary oxygen beyond postoperative day 3 (p = 0.53). Clinical signs of pneumonia tended to be more frequent in the ICPAP group (p = 0.06), yet the difference was not statistically significant. Comfort scores were similar in both groups (p = 0.43), although a sensation of claustrophobia during treatment was only experienced in the HCPAP group (11% vs. 0%, p = 0.03). Compared with ICPAP, using HCPAP was associated with similar oxygenation (i.e., PaO₂/FIO₂ ratio) and a similar risk of pulmonary complications. However, HCPAP treatment was associated with a higher sensation of claustrophobia.

Comparison of Clinical Effectiveness Between Ambroxol and N-Acetylcysteine in Surgical Patients: A Retrospective Cohort Study

Postoperative pulmonary complications (PPCs) are a major cause of postoperative morbidity, mortality, and longer hospital stays. Expectorants are widely used during the perioperative period to reduce PPCs. This study aimed to compare the clinical effectiveness between ambroxol (AMB) and N-acetylcysteine (NAC) in patients undergoing surgery. A multicenter, retrospective cohort study was conducted using deidentified medical records from hospital information system. Between July 1, 2015, and November 30, 2017, patients aged ≥18 years, who received intravenous AMB or nebulized NAC as the only expectorant therapy for >3 days during their hospitalization for thoracic, abdominal, and neurosurgery, were included in this study. The clinical outcomes were evaluated, and propensity score matching was used to adjust significant differences between 2 groups. A total of 4025 cases in the AMB group and 2062 in NAC group after propensity score matching were identified. The incidence of PPCs (13.9% vs 11.6%; P = .013), postoperative sputum suction (17.2% vs 8.0%; P < .001), intensive care unit admission after surgery (25.1% vs 22.5%; P = .024), and postoperative mechanical ventilation (22.3% versus 17.5%; P < .001) in the AMB group were all significantly higher than those in the NAC group. This study suggested that patients treated with NAC during the perioperative period had a significantly lower risk of PPCs. However, further prospective study is needed to ensure the replicability of our findings.

Nocturnal respiratory abnormalities among ward-level postoperative patients as detected by the Capnostream 20p monitor: A blinded observational study

PURPOSE

This prospective observational study aimed to establish the frequency of postoperative nocturnal respiratory abnormalities among patients undergoing major surgery who received ward-level care. These abnormalities may have implications for postoperative pulmonary complications (PPCs).

METHODS

Eligible patients underwent blinded noninvasive continuous capnography with pulse oximetry using the Capnostream™ 20p monitor over the first postoperative night. All patients received oxygen supplementation and patient-controlled opioid analgesia. The primary outcome was the number of prolonged apnea events (PAEs), defined as end-tidal carbon dioxide (EtCO2) ≤5 mmHg for 30-120 seconds or EtCO2 ≤5 mmHg for >120 seconds with oxygen saturation (SpO2) <85%. Secondary outcomes were the proportion of recorded time that physiological indices were aberrant, including the apnea index (AI), oxygen desaturation index (ODI), integrated pulmonary index (IPI), and SpO2. Exploratory analysis was conducted to assess the associations between PAEs, PPCs, and pre-defined factors.

RESULTS

Among 125 patients who had sufficient data for analysis, a total of 1800 PAEs occurred in 67 (53.4%) patients. The highest quartile accounted for 89.1% of all events. Amongst patients who experienced any PAEs, the median (IQR) number of PAE/patient was four (2-12). As proportions of recorded time (median (IQR)), AI, ODI, and IPI were aberrant for 12.4% (0-43.2%), 19.1% (2.0-57.1%), and 11.5% (3.1-33.3%) respectively. Only age, ARISCAT, and opioid consumption/kg were associated with PPCs.

CONCLUSIONS

PAE and aberrant indices were frequently detected on the first postoperative night. However, they did not correlate with PPCs. Future research should investigate the significance of detected aberrations.

Impact of sarcopenia on postoperative pulmonary complications after gastric cancer surgery: A retrospective cohort study

Background

Few studies have investigated the relationship between sarcopenia and postoperative pulmonary complications (PPCs) after gastric cancer surgery. This study aimed to explore the impact of sarcopenia on PPCs in patients who had undergone gastric cancer surgery.

Methods

We included patients who underwent a transabdominal radical gastrectomy between June 2016 and October 2020. Patients were divided into two groups according to the median prevalence rate of lumbar triplane skeletal muscle index (L3 SMI): sarcopenia group (≤37.5% percentile in male and female group) and non-sarcopenia group (>37.5% percentile in male and female group). Baseline characteristics, intraoperative and postoperative conditions, pulmonary complications, and overall complications were compared between the two groups. The primary outcome was the incidence of PPCs. The secondary outcomes were overall postoperative complications and length of stay (LOS).

Results

Among the 143 patients included, 50 had sarcopenia and 93 had not. Compared to the non-sarcopenia group, the sarcopenia group had a higher the incidence of PPCs (22.0% vs. 8.6%, P = 0.024). The incidence of overall postoperative complications in the sarcopenia group was higher than that in the non-sarcopenia group (36.00% vs. 20.43%, P = 0.043). There was no significant difference in the LOS between the two groups.

Conclusions

Our research indicates that sarcopenia, preoperative comorbidities, and longer duration of intraoperative oxygen saturation <95% were risk factors for PPCs. Sarcopenia is an independent risk factor for postoperative complications. Given that our results provided a correlation rather than causation, future prospective randomized trials are needed to confirm the relationship between sarcopenia and prognosis.

Muscular tissue desaturation and pneumonia in patients receiving lung cancer surgery: a cohort study

BACKGROUND

Post-operative pneumonia (POP) is a common complication of lung cancer surgery, and muscular tissue oxygenation is a root cause of post-operative complications. However, the association between muscular tissue desaturation and POP in patients receiving lung cancer surgery has not been specifically studied. This study aimed to investigate the potential use of intra-operative muscular tissue desaturation as a predictor of POP in patients undergoing lung cancer surgery.

METHODS

This cohort study enrolled patients (≥55 years) who had undergone lobectomy with one-lung ventilation. Muscular tissue oxygen saturation (SmtO 2 ) was monitored in the forearm (over the brachioradialis muscle) and upper thigh (over the quadriceps) using a tissue oximeter. The minimum SmtO 2 was the lowest intra-operative measurement at any time point. Muscular tissue desaturation was defined as a minimum baseline SmtO 2 of <80% for >15 s. The area under or above the threshold was the product of the magnitude and time of desaturation. The primary outcome was the association between intra-operative muscular tissue desaturation and POP within seven post-operative days using multivariable logistic regression. The secondary outcome was the correlation between SmtO 2 in the forearm and that in the thigh.

RESULTS

We enrolled 174 patients. The overall incidence of muscular desaturation (defined as SmtO 2 < 80% in the forearm at baseline) was approximately 47.1% (82/174). The patients with muscular desaturation had a higher incidence of pneumonia than those without desaturation (28.0% [23/82] vs. 12.0% [11/92]; P  = 0.008). The multivariable analysis revealed that muscular desaturation was associated with an increased risk of pneumonia (odds ratio: 2.995, 95% confidence interval: 1.080-8.310, P  = 0.035) after adjusting for age, American Society of Anesthesiologists status, Assess Respiratory Risk in Surgical Patients in Catalonia score, smoking, use of peripheral nerve block, propofol, and study center.

CONCLUSION

Muscular tissue desaturation, defined as a baseline SmtO 2 < 80% in the forearm, may be associated with an increased risk of POP.

TRIAL REGISTRATION

No. ChiCTR-ROC-17012627.

Postoperative prophylactic intermittent noninvasive ventilation versus usual postoperative care for patients at high risk of pulmonary complications: a multicentre randomised trial

BACKGROUND

Pulmonary complications are an important cause of morbidity and mortality after surgery. We evaluated the clinical effectiveness of noninvasive ventilation (NIV) in preventing postoperative acute respiratory failure.

METHODS

This is an open, multicentre randomised trial that included patients at high risk of postoperative pulmonary complications after elective or semi-urgent surgery with an Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score ≥45. Patients were randomly assigned to intermittent prophylactic face-mask NIV for 6-8 h day^-1 or usual postoperative care. The primary outcome was in-hospital acute respiratory failure within 7 days after surgery. Patients who underwent surgery and postoperative extubation were included in the modified intended-to-treat analysis. Results are presented as n (%) and odds ratios (ORs) with 95% confidence intervals.

RESULTS

Between November 2017 and October 2019, 266 patients were randomised and 253 included in the main analysis. Of these, 203 (80.2%) were male with a mean age of 68 (11) yr and an ARISCAT score of 53 (6); 237 subjects (93.7%) underwent cardiac or thoracic surgery. There were 125 patients allocated to prophylactic NIV and 128 to usual care. Unplanned treatment termination occurred in 58 subjects in the NIV group, which was linked to NIV discomfort for 36 subjects. There was no difference in the incidence of the primary outcome of postoperative acute respiratory failure between treatment groups (NIV: 30 of 125 subjects [24.0%] vs usual care: 35 of 128 subjects [27.3%]; OR 0.97 [0.90-1.04]; P=0.54).

CONCLUSIONS

Prophylactic NIV was difficult to implement after high-risk surgery because of low patient compliance. Prophylactic NIV did not prevent acute respiratory failure.

CLINICAL TRIAL REGISTRATION

NCT03629431 and EudraCT 2017-001011-36.

[Integral scales in assessing the risk of postoperative morbidity and mortality]

Annual number of surgeries exceeds 10 million In Russia, and this number is increasing every year. Searching for a scale or index determining the risk of postoperative complications and mortality is an important issue all over the world. The authors analyzed all available risk assessment scales for postoperative morbidity and mortality. The most significant ones in historical aspect and modern perspective grading systems were highlighted. We compared these indices with clinical recommendations and necessary preoperative preparation. Thus, these scales are valuable for surgeons and anesthesiologists to assess the risk, volume of surgical intervention and methods of preoperative management. However, they are not perfect and require improvement. Therefore, development of such scales is a priority objective of medicine in the foreseeable future.

Lasso-Based Machine Learning Algorithm for Predicting Postoperative Lung Complications in Elderly: A Single-Center Retrospective Study from China

Background

The predictive effect of systemic inflammatory factors on postoperative pulmonary complications in elderly patients remains unclear. In addition, machine learning models are rarely used in prediction models for elderly patients.

Patients and Methods

We retrospectively evaluated elderly patients who underwent general anesthesia during a 6-year period. Eligible patients were randomly assigned in a 7:3 ratio to the development group and validation group. The Least logistic absolute shrinkage and selection operator (LASSO) regression model and multiple logistic regression analysis were used to select the optimal feature. The discrimination, calibration and net reclassification improvement (NRI) of the final model were compared with "the Assess Respiratory Risk in Surgical Patients in Catalonia" (ARISCAT) model.

Results

Of the 9775 patients analyzed, 8.31% developed PPCs. The final model included age, preoperative SpO2, ANS (the Albumin/NLR Score), operation time, and red blood cells (RBC) transfusion. The concordance index (C-index) values of the model for the development cohort and the validation cohort were 0.740 and 0.748, respectively. The P values of the Hosmer-Lemeshow test in two cohorts were insignificant. Our model outperformed ARISCAT model, with C-index (0.740 VS 0.717, P = 0.003) and NRI (0.117, P < 0.001).

Conclusion

Based on LASSO machine learning algorithm, we constructed a prediction model superior to ARISCAT model in predicting the risk of PPCs. Clinicians could utilize these predictors to optimize prospective and preventive interventions in this patient population.

Update on preoperative evaluation and optimisation

The patients presenting for surgery today often belong to the extremes of age, have multiple co-morbidities, and undergo complex surgeries. This makes them more prone to morbidity and mortality. A detailed preoperative evaluation of the patient can contribute to reducing this mortality and morbidity. There are various risk indices and validated scoring systems and many of them need to be calculated using preoperative parameters. Their key objective is to identify patients vulnerable to complications and to return them to desirable functional activity as soon as possible. Any individual undergoing surgery should be optimised preoperatively, but special considerations should be given to patients with comorbidity, on multiple drugs, and undergoing high-risk surgery. The objective of this review is to put forth the latest trends in the preoperative evaluation and optimisation of patients undergoing noncardiac surgery and emphasise the importance of risk stratification in these patients.

Volume Incentive Spirometry Reduces Pulmonary Complications in Patients After Open Abdominal Surgery: A Randomized Clinical Trial

Objective

To compare the effect of diaphragmatic breathing and volume incentive spirometry (VIS) on hemodynamics, pulmonary function, and blood gas in patients following open abdominal surgery under general anesthesia.

Methods

A total of 58 patients who received open abdominal surgery were randomly assigned to the control group (n=29) undergoing diaphragmatic breathing exercises and the VIS group (n=29) undergoing VIS exercises. All the participants performed the six-minute walk test (6MWT) preoperatively to evaluate their functional capacity. Hemodynamic indexes, pulmonary function tests, and blood gas indexes were recorded before surgery and on the 1st, 3rd, and 5th postoperative day.

Results

The functional capacity was not significantly different between the two groups during the preoperative period (P >0.05). At 3 days and 5 days postoperatively, patients in the VIS group had a significantly higher SpO2 than that in the control group (P <0.05). Pulmonary function test values were reduced in both two groups postoperatively when compared to the preoperative values but improved for three and five days afterward (P <0.05). Of note, the significantly elevated levels of peak expiratory flow (PEF), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were observed on the 1st, 3rd, and 5th postoperative days in the VIS group compared with those in the control group (P <0.05). Besides, bass excess (BE), and pH values were significantly higher in the VIS group on the 1st postoperative day than those in the control group (P <0.05).

Conclusion

Diaphragmatic breathing and VIS could improve postoperative pulmonary function, but VIS exercise might be a better option for improving hemodynamics, pulmonary function, and blood gas for patients after open abdominal surgery, hence lowering the incidence of postoperative pulmonary complications.

Association between choice of reversal agent for neuromuscular block and postoperative pulmonary complications in patients at increased risk undergoing non-emergency surgery: STIL-STRONGER, a multicentre matched cohort study

BACKGROUND

Postoperative pulmonary complications are a source of morbidity after major surgery. In patients at increased risk of postoperative pulmonary complications we sought to assess the association between neuromuscular blocking agent reversal agent and development of postoperative pulmonary complications.

METHODS

We conducted a retrospective matched cohort study, a secondary analysis of data collected in the prior STRONGER study. Data were obtained from the Multicenter Perioperative Outcomes Group. Included patients were aged 18 yr and older undergoing non-emergency surgery under general anaesthesia with tracheal intubation with neuromuscular block and reversal, who were predicted to be at elevated risk of postoperative pulmonary complications. This risk was defined as American Society of Anesthesiologists Physical Status 3 or 4 in patients undergoing either intrathoracic or intra-abdominal surgery who were either aged >80 yr or underwent a procedure lasting >2 h. Cohorts were defined by reversal with neostigmine or sugammadex. The primary composite outcome was the occurrence of pneumonia or respiratory failure.

RESULTS

After matching by institution, sex, age (within 5 yr), body mass index, anatomic region of surgery, comorbidities, and neuromuscular blocking agent, 3817 matched pairs remained. The primary postoperative pulmonary complications outcome occurred in 224 neostigmine cases vs 100 sugammadex cases (5.9% vs 2.6%, odds ratio 0.41, P<0.01). After adjustment for unbalanced covariates, the adjusted odds ratio for the association between sugammadex use and the primary outcome was 0.39 (P<0.0001).

CONCLUSIONS

In a cohort of patients at increased risk for pulmonary complications compared with neostigmine, use of sugammadex was independently associated with reduced risk of subsequent development of pneumonia or respiratory failure.

The ARISCAT Risk Index as a Predictor of Pulmonary Complications After Thoracic Surgeries, Almoosa Specialist Hospital, Saudi Arabia

Background

Pulmonary complications after thoracic surgery are common and are associated with prolonged hospital stay, higher costs, and increased mortality. This study aimed to evaluate the value of The Assess Respiratory risk in Surgical Patients in Catalonia (ARISCAT) risk index in predicting pulmonary complications after thoracic surgery.

Methods

This retrospective study was conducted at Almoosa Specialist Hospital, Saudi Arabia, from August 2016 to August 2019 and included 108 patients who underwent thoracic surgery during the study period. Demographic data, ARISCAT risk index score, length of hospital stay, time of chest tube removal, postoperative complications, and time of discharge were recorded.

Results

The study involved 108 patients who met the inclusion criteria. Their mean age was 42.5 ± 18.9 years, and most of them were men (67.6%). Comorbid diseases were present in 53.7%, including mainly type 2 diabetes mellitus and hypertension. FEV1% was measured in 58 patients, with a mean of 71.1 ± 7.3%. The mean ARISCAT score was 39.3 ± 12.4 and ranged from 24 to 76, with more than one-third (35.2%) having a high score grade. The most common surgical procedures were thoracotomy in 47.2%, video-assisted thoracoscopic surgery (VATS) in 28.7%, and mediastinoscopy in 17.6%. Postoperative pulmonary complications (PPCs) occurred in 22 patients (20.4%), mainly pneumonia and atelectasis (9.2%). PPCs occurred most frequently during thoracotomy (68.2%), followed by VATS (13.6%), and mediastinoscopy (9.1%). Multinomial logistic regression of significant risk factors showed that lower FEV1% (OR = 0.88 [0.79-0.98]; p=0.017), longer ICU length of stay (OR = 1.53 [1.04-2.25]; p=0.033), a higher ARISCAT score (OR = 1.22 [1.02-1.47]; p=0.040), and a high ARISCAT grade (OR = 2.77 [1.06-7.21]; p=0.037) were significant predictors of the occurrence of postoperative complications.

Conclusion

ARISCAT scoring system, lower FEV1% score, and longer ICU stay were significant predictors of postoperative complications. In addition, thoracotomy was also found to be associated with PPCs.

Driving pressure-guided ventilation and postoperative pulmonary complications in thoracic surgery: a multicentre randomised clinical trial

BACKGROUND

Airway driving pressure, easily measured as plateau pressure minus PEEP, is a surrogate for alveolar stress and strain. However, the effect of its targeted reduction remains unclear.

METHODS

In this multicentre trial, patients undergoing lung resection surgery were randomised to either a driving pressure group (n=650) receiving an alveolar recruitment/individualised PEEP to deliver the lowest driving pressure or to a conventional protective ventilation group (n=650) with fixed PEEP of 5 cm H₂O. The primary outcome was a composite of pulmonary complications within 7 days postoperatively.

RESULTS

The modified intention-to-treat analysis included 1170 patients (mean [standard deviation, sd]; age, 63 [10] yr; 47% female). The mean driving pressure was 7.1 cm H₂O in the driving pressure group vs 9.2 cm H₂O in the protective ventilation group (mean difference [95% confidence interval, CI]; -2.1 [-2.4 to -1.9] cm H₂O; P<0.001). The incidence of pulmonary complications was not different between the two groups: driving pressure group (233/576, 40.5%) vs protective ventilation group (254/594, 42.8%) (risk difference -2.3%; 95% CI, -8.0% to 3.3%; P=0.42). Intraoperatively, lung compliance (mean [sd], 42.7 [12.4] vs 33.5 [11.1] ml cm H₂O^-1; P<0.001) and Pa_o2 (median [inter-quartile range], 21.5 [14.5 to 30.4] vs 19.5 [13.5 to 29.1] kPa; P=0.03) were higher and the need for rescue ventilation was less frequent (6.8% vs 10.8%; P=0.02) in the driving pressure group.

CONCLUSIONS

In lung resection surgery, a driving pressure-guided ventilation improved pulmonary mechanics intraoperatively, but did not reduce the incidence of postoperative pulmonary complications compared with a conventional protective ventilation.

CLINICAL TRIAL REGISTRATION

NCT04260451.

Risk factors for pulmonary complications after laparoscopic liver resection: a multicenter retrospective analysis

BACKGROUND

Postoperative pulmonary complications (PPCs) are among the most common complications after liver resection. Although the application of laparoscopy has reduced the incidence of PPCs, the rate of PPCs after laparoscopic liver resection (LLR) remains high and the risk factors for the same are unclear. Therefore, this study aimed to determine the risk factors for PPCs after LLR.

METHODS

In this multicenter study, 296 patients underwent LLR from January 2019 to December 2020. Demographic data, pathological variables, and perioperative variables were reviewed. Univariate and multivariate analyses were performed to identify the independent risk factors for PPCs.

RESULTS

Of the 296 patients, 80 (27.0%) developed PPCs. Patients with PPCs had significantly increased total costs, operation costs, length of stays, and postoperative hospital stays. Multivariate analysis identified three independent risk factors for PPCs after LLR: smoking [Odds ratio (OR): 5.413, 95% confidence intervals (CI): 2.446-11.978, P =  < 0.001], location of lesion in segment 7 or 8 (OR 3.134, 95% CI 1.593-6.166, P = 0.001), duration of liver ischemia (OR 1.038, 95% CI 1.022-1.054, P < 0.001), and presence of intraoperative hypothermia (OR 3.134, 95% CI 1.593-6.166, P < 0.001).

CONCLUSION

Smoking, location of lesion in segment 7 or 8, duration of liver ischemia and intraoperative hypothermia were independent risk factors for PPCs which significantly increased the length of stays and burden of healthcare costs.

Postanesthesia complications in pediatric patients with previous SARS-CoV-2 infection: A cohort study

BACKGROUND

Children with SARS-CoV-2 infection are at increased risk for postanesthesia complications. There is minimal data regarding how long that elevated complication risk persists beyond initial SARS-CoV-2 diagnosis.

AIMS

We investigated postanesthesia complications in children with SARS-CoV-2 infection within 90 days of diagnosis.

METHODS

We completed a single-center, retrospective, case-control study of pediatric patients with confirmed SARS-CoV-2 infection within 90 days undergoing anesthesia between January 3-October 7, 2020. Each SARS-CoV-2 positive patient was matched 1:2 by age and type of procedure with a non-SARS-CoV-2 cohort. The primary outcome was the rate of all postanesthesia complications within 30 days of the procedure, defined as unplanned escalations of care within 48 h, cardiac, respiratory, thrombotic, and hemorrhagic events within 30 days. Secondary outcomes were 30-day mortality and hospital length of stay.

RESULTS

Of the 341 patients included, 114 patients were SARS-CoV-2 positive and 227 were SARS-CoV-2 negative. Patients with a positive test 0-7 days prior to anesthesia had an increased risk difference in all postanesthesia complications within 30 days (19.9, 95% CI [4.7, 35.1], p = .001) and increased risk difference in length of hospital stay (7.8, 95% CI [1.2, 14.4], p < .001). Patients who underwent anesthesia greater than 42 days from SARS-CoV-2 diagnosis had an increased risk difference in cardiac complications within 30 days (4.3, 95% CI [0.9, 10.0], p = .029). There was no increased hospital length of stay among SARS-CoV-2 positive patients diagnosed greater than 8 days before anesthetic. There were no deaths within 30 days of anesthetic.

CONCLUSIONS

Postanesthesia complications are higher in children who undergo anesthesia within 7 days of SARS-CoV-2 diagnosis. Additional cardiac risk may persist beyond the immediate period of initial diagnosis. Larger samples are needed to further evaluate the risk of delayed postanesthesia complications and guide optimal timing of surgery.

[The perioperative role of high-flow cannula oxygen (HFNO)]

High-flow nasal cannula oxygen (HFNO) is commonly used during the perioperative period. Its numerous physiological benefits, satisfactory tolerance and ease of use have led to its widespread application in intensive care and post-anesthesia care units. HFNO is also used in the operating theater in multiple indications: as oxygen supplementation (associated with pressurization) prior to orotracheal intubation; in digestive and bronchial endoscopies, especially in patients at risk of hypoxemia; and in intraoperative surgery requiring spontaneous ventilation (ENT, thoracic surgery…). During the postoperative period, HFNO can be used in a curative strategy for respiratory failure or in a prophylactic strategy to prevent reintubation. In a curative approach, HFNO seems of interest following cardiac or thoracic surgery but has not been evaluated in respiratory failure subsequent to abdominal surgery, in which case noninvasive ventilation remains the gold standard. The risk of respiratory complications depends on type of surgery and on patient comorbidities. As prophylaxis, HFNO is currently preferred to conventional oxygen therapy after cardiac or thoracic surgery, especially in patients at high risk of respiratory complications. For the clinician, it is important to acknowledge the limits of HFNO and to closely monitor patients receiving HFNO, the objective being to avoid delays in intubation that could lead to increased mortality.

An Augmented Reality (AR) App Enhances the Pulmonary Function and Potency/Feasibility of Perioperative Rehabilitation in Patients Undergoing Orthopedic Surgery

Perioperative rehabilitation is crucial for patients receiving surgery in order to reduce complications and mortality. Conventional methods such as verbal instructions and pre-recorded video are commonly used, but several disadvantages exist. Therefore, we developed an augmented reality (AR) app that includes respiration training, resistance muscle training, and walking training for surgery preparation. The aim of this pilot study was to compare the effects of AR-based training rehabilitation programs with conventional (non-AR-based) programs considering the objective pulmonary function and subjective feasibility and potency in orthopedic patients. This prospective study was conducted in a medical center in Taiwan between 2018 to 2021. Sixty-six patients undergoing elective orthopedic surgery were allocated with a 1:1 ratio to non-AR or AR groups according to their wishes. After training, the inspiratory flow rate of the AR group was higher than that of the non-AR group pre-operatively. As for the subjective assessment, the feasibility (level of confidence and anxiety reduction) and potency (cooperation and educative effect) were superior in AR-based training, compared with the conventional training model. Our study showed that patients using our AR app had better subjective and objective outcomes compared with a conventional model for perioperative rehabilitation.

The association between initial calculated driving pressure at the induction of general anesthesia and composite postoperative oxygen support

PURPOSE

Early discontinuation of postoperative oxygen support (POS) would partially depend on the innate pulmonary physics. We aimed to examine if the initial driving pressure (dP) at the induction of general anesthesia (GA) predicted POS prolongation.

METHODS

We conducted a single-center retrospective study using the facility's database. Consecutive subjects over 2 years were studied to determine the change in odds ratio (OR) for POS prolongation of different dP classes at GA induction. The dP (cmH₂O) was calculated as the ratio of tidal volume (mL) over dynamic Crs (mL/cmH₂O) regardless of the respiratory mode. The adjusted OR was calculated using the logistic regression model of multivariate analysis. Moreover, we performed a secondary subgroup analysis of age and the duration of GA.

RESULTS

We included 5,607 miscellaneous subjects. Old age, high scores of American Society of Anesthesiologist physical status, initial dP, and long GA duration were associated with prolonged POS. The dP at the induction of GA (7.78 [6.48, 9.45] in median [interquartile range]) was categorized into five classes. With the dP group of 6.5-8.3 cmH₂O as the reference, high dPs of 10.3-13 cmH₂O and ≥ 13 cmH₂O were associated with significant prolongation of POS (adjusted OR, 1.62 [1.19, 2.20], p = 0.002 and 1.92 [1.20, 3.05], p = 0.006, respectively). The subgroup analysis revealed that the OR for prolonged POS of high dPs disappeared in the aged and ≥ 6 h anesthesia time subgroup.

CONCLUSIONS

High initial dPs ≥ 10 cmH₂O at GA induction predicted longer POS than those of approximately 7 cmH₂O. High initial dPs were, however, a secondary factor for prolongation of postoperative hypoxemia in old age and prolonged surgery.

Positive SARS-CoV-2 detection on intraoperative nasopharyngeal viral testing is not associated with worse outcomes for asymptomatic elective surgical patients

Background

It has been demonstrated that surgical patients with COVID-19 are at increased risk for postoperative complications. However, this association has not been tested in asymptomatic elective surgical patients.

Methods

A retrospective cohort study among elective gynecological and spine surgery patients at a single tertiary medical center from July 2020 through April 2022 (n = 1,130) was performed. The primary endpoint was prolonged (>75th percentile for the corresponding surgical service) length of stay. Secondary endpoints included postoperative respiratory complications, duration of supplemental oxygen therapy, and other major adverse events. The association between SARS-CoV-2 detection and the above outcomes was investigated with univariate and multivariable analyses.

Findings

Of 1,130 patients who met inclusion criteria, 30 (2.7%) experienced intraoperative detection of SARS-CoV-2. Those with intraoperative viral detection did not experience an increased incidence of prolonged length of stay [16.7% vs. 23.2%; RR, 0.72 (95% CI, 0.32-1.61); P = 0.531] nor did they have a longer mean length of stay (4.1 vs. 3.9 days; P = 0.441). Rates of respiratory complications [3.3% vs. 2.9%; RR, 1.15 (95% CI, 0.16-8.11); P = 0.594] and mean duration of supplemental oxygen therapy (9.7 vs. 9.3 h; P = 0.552) were similar as well. All other outcomes were similar in those with and without intraoperative detection of SARS-CoV-2 (all P > 0.05).

Interpretation

Asymptomatic patients with incidental detection of SARS-CoV-2 on intraoperative testing do not experience disproportionately worse outcomes in the elective spine and gynecologic surgical population.

The impact of driving pressure on postoperative pulmonary complication in patients with different respiratory spirometry

Risk factors for postoperative pulmonary complication (PPC) have not been determined according to preoperative respiratory spirometry. Thus, we aimed to find contributors for PPC in patients with restrictive or normal spirometric pattern. We analyzed 654 patients (379 with normal and 275 with restrictive spirometric pattern). PPCs comprised respiratory failure, pleural effusion, atelectasis, respiratory infection, and bronchospasm. We analyzed the association between perioperative factors and PPC using binary logistic regression. In particular, we conducted subgroup analysis on the patients stratified according to preoperative spirometry. Of 654 patients, 27/379 patients (7.1%) with normal spirometric pattern and 33/275 patients (12.0%) with restrictive spirometric pattern developed PPCs. Multivariable analysis demonstrated that high driving pressure was the only intraoperative modifiable factor increasing PPC risk (OR = 1.13 [1.02-1.25], p = 0.025). In the subgroup of patients with restrictive spirometric pattern, intraoperative driving pressure was significantly associated with PPC (OR = 1.21 [1.05-1.39], p = 0.009), whereas driving pressure was not associated with PPC in patients with normal spirometric pattern (OR = 1.04 [0.89-1.21], p = 0.639). In patients with restrictive spirometric pattern, greater intraoperative driving pressure is significantly associated with increased PPC risk. In contrast, intraoperative driving pressure is not associated with PPC in patients with normal spirometric pattern.

Effect of postextubation noninvasive ventilation with active humidification vs high-flow nasal cannula on reintubation in patients at very high risk for extubation failure: a randomized trial

PURPOSE

High-flow nasal cannula (HFNC) oxygen therapy was noninferior to noninvasive ventilation (NIV) for preventing reintubation in a heterogeneous population at high-risk for extubation failure. However, outcomes might differ in certain subgroups of patients. Thus, we aimed to determine whether NIV with active humidification is superior to HFNC in preventing reintubation in patients with ≥ 4 risk factors (very high risk for extubation failure).

METHODS

Randomized controlled trial in two intensive care units in Spain (June 2020‒June 2021). Patients ready for planned extubation with ≥ 4 of the following risk factors for reintubation were included: age > 65 years, Acute Physiology and Chronic Health Evaluation II score > 12 on extubation day, body mass index > 30, inadequate secretions management, difficult or prolonged weaning, ≥ 2 comorbidities, acute heart failure indicating mechanical ventilation, moderate-to-severe chronic obstructive pulmonary disease, airway patency problems, prolonged mechanical ventilation, or hypercapnia on finishing the spontaneous breathing trial. Patients were randomized to undergo NIV with active humidification or HFNC for 48 h after extubation. The primary outcome was reintubation rate within 7 days after extubation. Secondary outcomes included postextubation respiratory failure, respiratory infection, sepsis, multiorgan failure, length of stay, mortality, adverse events, and time to reintubation.

RESULTS

Of 182 patients (mean age, 60 [standard deviation (SD), 15] years; 117 [64%] men), 92 received NIV and 90 HFNC. Reintubation was required in 21 (23.3%) patients receiving NIV vs 35 (38.8%) of those receiving HFNC (difference -15.5%; 95% confidence interval (CI) -28.3 to -1%). Hospital length of stay was lower in those patients treated with NIV (20 [12‒36.7] days vs 26.5 [15‒45] days, difference 6.5 [95%CI 0.5-21.1]). No additional differences in the other secondary outcomes were observed.

CONCLUSIONS

Among adult critically ill patients at very high-risk for extubation failure, NIV with active humidification was superior to HFNC for preventing reintubation.

Evaluation of continuous aspiration of subglottic secretions in prevention of microaspiration during general anesthesia: a randomized controlled pilot study

AIM

To assess the difference between endotracheal tubes (ETT) with continuous suction of subglottic secretions (CASS) and standard ETT in preventing secretions movement from the pharynx into the trachea, past the inflated cuff during general anesthesia.

METHODS

This randomized, controlled trial enrolled 50 patients who underwent general anesthesia for elective abdominal surgery lasting longer than two hours. They received either ETT with CASS: Teleflex ISIS HVT (GISIS, n=17) or Mallinckrodt TaperGuard Evac (GEvac, n=17), or ETT without suction: Mallinckrodt Intermediate Hi-Lo (GStand, n=16). Methylene blue dye solution (10 mL) was delivered into the hypopharynx every 60 minutes. Subglottic secretions were continuously suctioned. Fiberoptic bronchoscopy was performed every 20 minutes and during tracheal extubation to evaluate the dye location.

RESULTS

The groups did not differ in age, sex, body mass index, race, American Society of Anesthesiologists status, and surgery type. Dye migrated past the inflated cuff into the distal trachea in no patient with ETT with CASS and in 13% of patients with standard ETT. On tracheal extubation, dye migrated into the distal trachea more often in the GStand group (56%), compared with the GEvac (13%) and GISIS group (29%) (P=0.045). The GISIS group had 26±19 mL of secretions suctioned from above the inflated cuff, while the GEvac group had 13±10 mL (P=0.05).

CONCLUSION

Compared with standard ETT, ETT with CASS efficiently removed secretions during general anesthesia, prevented secretions from migrating past the inflated cuff, and significantly reduced the amount of secretions that reached the distal airways on tracheal extubation.

Complications Following Elective Major Noncardiac Surgery Among Patients With Prior SARS-CoV-2 Infection

IMPORTANCE

There is an urgent need for evidence to inform preoperative risk assessment for the millions of people who have had SARS-CoV-2 infection and are awaiting elective surgery, which is critical to surgical care planning and informed consent.

OBJECTIVE

To assess the association of prior SARS-CoV-2 infection with death, major adverse cardiovascular events, and rehospitalization after elective major noncardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study included adults who had received a polymerase chain reaction test for SARS-CoV-2 infection within 6 months prior to elective major noncardiac surgery in Ontario, Canada, between April 2020 and October 2021, with 30 days follow-up.

EXPOSURES

Positive SARS-CoV-2 polymerase chain reaction test result.

MAIN OUTCOMES AND MEASURES

The main outcome was the composite of death, major adverse cardiovascular events, and all-cause rehospitalization within 30 days after surgery.

RESULTS

Of 71 144 patients who underwent elective major noncardiac surgery (median age, 66 years [IQR, 57-73 years]; 59.8% female), 960 had prior SARS-CoV-2 infection (1.3%) and 70 184 had negative test results (98.7%). Prior infection was not associated with the composite risk of death, major adverse cardiovascular events, and rehospitalization within 30 days of elective major noncardiac surgery (5.3% absolute event rate [n = 3770]; 960 patients with a positive test result; adjusted relative risk [aRR], 0.91; 95% CI, 0.68-1.21). There was also no association between prior infection with SARS-CoV-2 and postoperative outcomes when the time between infection and surgery was less than 4 weeks (aRR, 1.15; 95% CI, 0.64-2.09) or less than 7 weeks (aRR, 0.95; 95% CI, 0.56-1.61) and among those who were previously vaccinated (aRR, 0.81; 95% CI, 0.52-1.26).

CONCLUSIONS AND RELEVANCE

In this study, prior infection with SARS-CoV-2 was not associated with death, major adverse cardiovascular events, or rehospitalization following elective major noncardiac surgery, although low event rates and wide 95% CIs do not preclude a potentially meaningful increase in overall risk.

Practice of oxygen use in anesthesiology – a survey of the European Society of Anaesthesiology and Intensive Care

Background

Oxygen is one of the most commonly used drugs by anesthesiologists. The World Health Organization (WHO) gave recommendations regarding perioperative oxygen administration, but the practice of oxygen use in anesthesia, critical emergency, and intensive care medicine remains unclear.

Methods

We conducted an online survey among members of the European Society of Anaesthesiology and Intensive Care (ESAIC). The questionnaire consisted of 46 queries appraising the perioperative period, emergency medicine and in the intensive care, knowledge about current recommendations by the WHO, oxygen toxicity, and devices for supplemental oxygen therapy.

Results

Seven hundred ninety-eight ESAIC members (2.1% of all ESAIC members) completed the survey. Most respondents were board-certified and worked in hospitals with > 500 beds. The majority affirmed that they do not use specific protocols for oxygen administration. WHO recommendations are unknown to 42% of respondents, known but not followed by 14%, and known and followed by 24% of them. Respondents prefer inspiratory oxygen fraction (FiO₂) ≥80% during induction and emergence from anesthesia, but intraoperatively < 60% for maintenance, and higher FiO₂ in patients with diseased than non-diseased lungs. Postoperative oxygen therapy is prescribed more commonly according to peripheral oxygen saturation (SpO₂), but shortage of devices still limits monitoring. When monitoring is used, SpO₂ ≤ 95% is often targeted. In critical emergency medicine, oxygen is used frequently in patients aged ≥80 years, or presenting with respiratory distress, chronic obstructive pulmonary disease, myocardial infarction, and stroke. In the intensive care unit, oxygen is mostly targeted at 96%, especially in patients with pulmonary diseases.

Conclusions

The current practice of perioperative oxygen therapy among respondents does not follow WHO recommendations or current evidence, and access to postoperative monitoring devices impairs the individualization of oxygen therapy. Further research and additional teaching about use of oxygen are necessary.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01884-2.

Increased diaphragm echodensity correlates with postoperative pulmonary complications in patients after major abdominal surgery: a prospective observational study

Background

Associated with increased morbidity and mortality, postoperative pulmonary complications (PPCs) often occur after major abdominal surgery. Diaphragmatic dysfunction is suggested to play an important role in the development of PPCs and diaphragm echodensity can be used as an indicator of diaphragm function. This study aimed to determine whether diaphragm echodensity could predict the occurrence of PPCs in patients after major abdominal surgery.

Methods

Diaphragm ultrasound images of patients after major abdominal surgery were collected during spontaneous breathing trials. Echodensity was quantified based on the right-skewed distribution of grayscale values (50th percentile, ED50; 85th percentile, ED85; mean, EDmean). Intra- and inter-analyzer measurement reproducibility was determined. Outcomes including occurrence of PPCs, reintubation rate, duration of ventilation, and length of ICU stay were recorded.

Results

Diaphragm echodensity was measured serially in 117 patients. Patients who developed PPCs exhibited a higher ED50 (35.00 vs. 26.00, p < 0.001), higher ED85 (64.00 vs. 55.00, p < 0.001) and higher EDmean (39.32 vs. 33.98, p < 0.001). In ROC curve analysis, the area under the curve of ED50 for predicting PPCs was 0.611. The optimal ED50 cutoff value for predicting the occurrence of PPCs was 36. According to this optimal ED50 cutoff value, patients were further divided into a high-risk group (ED50 > 36, n = 35) and low-risk group (ED50 ≤ 36, n = 82). Compared with the low-risk group, the high-risk group had a higher incidence of PPCs (unadjusted p = 0.003; multivariate-adjusted p < 0.001).

Conclusion

Diaphragm echodensity can be feasibly and reproducibly measured in mechanically ventilated patients. The increase in diaphragm echodensity during spontaneous breathing trials was related to an increased risk of PPCs in patients after major abdominal surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02194-6.

Effect of ventilation mode on postoperative pulmonary complications following lung resection surgery: a randomised controlled trial

The effect of intra-operative mechanical ventilation modes on pulmonary outcomes after thoracic surgery with one-lung ventilation has not been well established. We evaluated the impact of three common ventilation modes on postoperative pulmonary complications in patients undergoing lung resection surgery. In this two-centre randomised controlled trial, 1224 adults scheduled for lung resection surgery with one-lung ventilation were randomised to one of three groups: volume-controlled ventilation; pressure-controlled ventilation; and pressure-control with volume guaranteed ventilation. Enhanced recovery after surgery pathways and lung-protective ventilation protocols were implemented in all groups. The primary outcome was a composite of postoperative pulmonary complications within the first seven postoperative days. The outcome occurred in 270 (22%), with 87 (21%) in the volume control group, 89 (22%) in the pressure control group and 94 (23%) in the pressure-control with volume guaranteed group (p = 0.831). The secondary outcomes also did not differ across study groups. In patients undergoing lung resection surgery with one-lung ventilation, the choice of ventilation mode did not influence the risk of developing postoperative pulmonary complications. This is the first randomised controlled trial examining the effect of three ventilation modes on pulmonary outcomes in patients undergoing lung resection surgery.

Preoperative Evaluation for Noncardiac Surgery

The previous In the Clinic that addressed preoperative evaluation for noncardiac surgery was published in December 2016. This update reaffirms much of the information in the previous version and provides new information that has accumulated since then. The goal of preoperative assessment is to identify the risk for postoperative complications so health care teams can more fully understand how to implement strategies to mitigate risks before and after the operation.

Distribution of ventilation and oxygenation in surgical obese patients ventilated with high versus low positive end-expiratory pressure: A substudy of a randomised controlled trial

BACKGROUND

Intra-operative ventilation using low/physiological tidal volume and positive end-expiratory pressure (PEEP) with periodic alveolar recruitment manoeuvres (ARMs) is recommended in obese surgery patients.

OBJECTIVES

To investigate the effects of PEEP levels and ARMs on ventilation distribution, oxygenation, haemodynamic parameters and cerebral oximetry.

DESIGN

A substudy of a randomised controlled trial.

SETTING

Tertiary medical centre in Geneva, Switzerland, between 2015 and 2018.

PATIENTS

One hundred and sixty-two patients with a BMI at least 35 kg per square metre undergoing elective open or laparoscopic surgery lasting at least 120 min.

INTERVENTION

Patients were randomised to PEEP of 4 cmH 2 O ( n  = 79) or PEEP of 12 cmH 2 O with hourly ARMs ( n  = 83).

MAIN OUTCOME MEASURES

The primary endpoint was the fraction of ventilation in the dependent lung as measured by electrical impedance tomography. Secondary endpoints were the oxygen saturation index (SaO 2 /FIO 2 ratio), respiratory and haemodynamic parameters, and cerebral tissue oximetry.

RESULTS

Compared with low PEEP, high PEEP was associated with smaller intra-operative decreases in dependent lung ventilation [-11.2%; 95% confidence interval (CI) -8.7 to -13.7 vs. -13.9%; 95% CI -11.7 to -16.5; P  = 0.029], oxygen saturation index (-49.6%; 95% CI -48.0 to -51.3 vs. -51.3%; 95% CI -49.6 to -53.1; P  < 0.001) and a lower driving pressure (-6.3 cmH 2 O; 95% CI -5.7 to -7.0). Haemodynamic parameters did not differ between the groups, except at the end of ARMs when arterial pressure and cardiac index decreased on average by -13.7 mmHg (95% CI -12.5 to -14.9) and by -0.54 l min -1  m -2 (95% CI -0.49 to -0.59) along with increased cerebral tissue oximetry (3.0 and 3.2% on left and right front brain, respectively).

CONCLUSION

In obese patients undergoing abdominal surgery, intra-operative PEEP of 12 cmH 2 O with periodic ARMs, compared with intra-operative PEEP of 4 cmH 2 O without ARMs, slightly redistributed ventilation to dependent lung zones with minor improvements in peripheral and cerebral oxygenation.

TRIAL REGISTRATION

NCT02148692, https://clinicaltrials.gov/ct2.

Biomarkers predicting the 30‑day mortality of patients who underwent elective surgery and were infected with SARS‑CoV‑2 during the post‑operative period: A retrospective study

The coronavirus disease 2019 (COVID-19) pandemic is a significant global concern that has had major implications for the healthcare system. Patients with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) undergoing elective or emergency surgical procedures have a substantial risk of mortality and peri-operative complications. The present study aimed to describe the characteristics of patients who underwent elective surgery and developed nosocomial SARS-CoV-2 infection post-surgery. Patients who underwent thoracic, upper and lower abdominal or peripheral elective surgery with a polymerase chain reaction diagnosis of COVID-19, at 3-7 days after the surgery, were enrolled in the present retrospective study. Demographics, vaccination status against SARS-CoV-2, Charlson comorbidity index (CCI) and laboratory data were recorded upon admission to the hospital unit. In total, 116 subjects (80 males, 36 females; mean age, 67.31±16.83 years) fulfilling the inclusion criteria were identified. Among the 116 participants, 14 (12.1%) were intubated. From the 116 individuals analyzed, 84 were alive after 30 days (survivors), and 32 had succumbed to the disease (non-survivors). The mortality rate was 27.6% (32/116). The non-survivors had an older age and a higher CCI score. At the evaluation upon admission to the hospital unit, the survivors presented with higher serum albumin levels and a higher number of blood lymphocytes. In addition, the survivors exhibited lower levels of lactate dehydrogenase, aspartate aminotransferase, alkaline phosphatase (ALP) and C-reactive protein (CRP), as well as a higher neutrophil to lymphocyte ratio (NLR) and CRP to albumin ratio (CAR) (P<0.05). The patients that were intubated had higher levels of gamma glutamyl-transferase (GGT), ALP and ferritin, as well as a higher NLR and platelet to lymphocyte ratio upon admission to the hospital unit (P<0.05). According to the Cox proportional hazards multivariate regression analysis, the only independent predictors of mortality and intubation were ALP and GGT upon admission, respectively (P<0.05). On the whole, the findings of the present study suggest that more stringent guidelines are required in order to prevent infection during the post-operative period.

Effects of propofol and inhaled anesthetics on postoperative complications for the patients undergoing one lung ventilation: A meta-analysis

INTRODUCTION

With the widespread use of one-lung ventilation (OLV) in thoracic surgery, it is unclear whether maintenance anesthetics such as propofol and inhaled anesthetics are associated with postoperative complications. The purpose of this study was to compare the effects of propofol and inhaled anesthetics on postoperative complications in OLV patients.

METHODS

PubMed, EMBASE, Medline, and Cochrane Library were searched for relevant randomized controlled trials until 09/2021. All randomized controlled trials comparing the effect of propofol versus inhaled anesthetics on postoperative complications in OLV patients were included. All randomized controlled trials comparing:(a) major complications (b) postoperative pulmonary complications (c) postoperative cognitive function (MMSE score) (d) length of hospital stay (e) 30-day mortality, were included.

RESULTS

Thirteen randomized controlled trials involving 2522 patients were included in the analysis. Overall, there was no significant difference in major postoperative complications between the inhaled anesthetic and propofol groups (OR 0.78, 95%CI 0.54 to 1.13, p = 0.19; I2 = 0%). However, more PPCs were detected in the propofol group compared to the inhalation anesthesia group (OR 0.62, 95%CI 0.44 to 0.87, p = 0.005; I2 = 37%). Both postoperative MMSE score (SMD -1.94, 95%CI -4.87 to 0.99, p = 0.19; I2 = 100%) and hospital stay (SMD 0.05, 95%CI -0.29 to 0.39, p = 0.76; I2 = 73%) were similar between the two groups. The 30-day mortality rate was also not significantly different between groups (OR 0.79, 95%CI 0.03 to 18, p = 0.88; I2 = 63%).

CONCLUSIONS

In patients undergoing OLV, general anesthesia with inhaled anesthetics reduced PPC compared to propofol, but did not provide clear benefits on other major complications, cognitive function, length of hospital stay, or mortality.

Identification of risk factors for postoperative pulmonary complications in general surgery patients in a low-middle income country

BACKGROUND

Postoperative pulmonary complications (PPCs) are an important cause of perioperative morbidity and mortality. Although risk factors for PPCs have been identified in high-income countries, less is known about PPCs and their risk factors in low- and middle-income countries, such as South Africa. This study examined the incidence of PPCs and their associated risk factors among general surgery patients in a public hospital in the province of KwaZulu-Natal, South Africa to inform future quality improvement initiatives to decrease PPCs in this clinical population.

METHODS

A retrospective secondary analysis of adult patients with general surgery admissions from January 1, 2013 to December 31, 2017 was conducted using data from the health system's Hybrid Electronic Medical Registry. The sample was comprised of 5352 general surgery hospitalizations. PPCs included pneumonia, atelectasis, acute respiratory distress syndrome, pulmonary edema, pulmonary embolism, prolonged ventilation, hemothorax, pneumothorax, and other respiratory morbidity which encompassed empyema, aspiration, pleural effusion, bronchopleural fistula, and lower respiratory tract infection. Risk factors examined were age, tobacco use, number and type of pre-existing comorbidities, emergency surgery, and number and type of surgeries. Bivariate and multivariable logistic regression models were conducted to identify risk factors for developing a PPC.

RESULTS

The PPC rate was 7.8%. Of the 418 hospitalizations in which a patient developed a PPC, the most common type of PPC was pneumonia (52.4%) and the mortality rate related to the PPC was 11.7%. Significant risk factors for a PPC were increasing age, greater number of comorbidities, emergency surgery, greater number of general surgeries, and abdominal surgery.

CONCLUSIONS

PPCs are common in general surgery patients in low- and middle-income countries, with similar rates observed in high-income countries. These complications worsen patient outcomes and increase mortality. Quality improvement initiatives that employ resource-conscious methods are needed to reduce PPCs in low- and middle-income countries.