Postoperative Respiratory Muscle Dysfunction

Effect of short-term exercise-based prehabilitation program for patients undergoing liver cancer surgery: A randomized controlled trial

BACKGROUND

Patients with liver cancer usually experience postoperative complications and reduced perioperative functional capacity. This study aimed to assess the effect of a short-term, exercise-based prehabilitation program on postoperative clinical outcomes and perioperative functional capacity in patients with liver cancer undergoing hepatectomy.

METHODS

This single-center, prospective, open-labeled randomized controlled trial was conducted with 205 patients. Patients in the prehabilitation group (n = 104) received a 1-week exercise intervention program before surgery, including aerobic and resistance exercises, and respiratory training. Patients in the control group (n = 101) received the usual clinical care. The assessors were blinded to the patient allocation. The primary outcome was the incidence of postoperative pulmonary complication during hospitalization, which the multivariate logistic regression model analyzed. Other outcomes included functional capacity measured as the 6-minute walk distance, postoperative complications, length of stay, hospital readmissions, hospitalization cost, and patient-reported outcomes. Post hoc subgroup analyses were performed.

RESULTS

The median duration of prehabilitation was 8 days. There was no between-group difference in the incidence of postoperative pulmonary complication (adjusted odds ratio, 0.70; 95% confidence interval, 0.37-1.29; P = .249). There were no differences in postoperative clinical outcomes and patient-reported outcomes, except for 6-minute walk distance (33.36 m higher in the prehabilitation group, 95% CI, 22.02-44.70; P < .001).

CONCLUSION

This exercise prehabilitation program did not affect postoperative clinical outcomes or patient-reported outcomes of patients with liver cancer, but it showed improvement in preoperative functional capacity.

Mortality 30, 60, and 90 Days After Discharge Is Greater in Patients Who Experienced Postoperative Respiratory Depression and Pulmonary Complication

Upon the induction of general anesthesia, a predictable sequence of physiological changes occurs within the respiratory and neuromuscular systems. The sequelae of these changes include an assortment of postoperative pulmonary complications (PPCs), including postoperative respiratory depression (PORD), that are observed during the immediate postoperative period and in the post-anesthesia care unit (PACU). These adverse events are anticipated, because several of the drugs that are used during surgery (e.g., opioids, which are traditionally used to manage pain during and after surgery), albeit therapeutically beneficial, have these adverse effects as part of their pharmacology. Nevertheless, the effects are traditionally considered transitory. However, several studies provide evidence suggesting that PPC-related morbidity and mortality extend 30, 60, and even 90 days after discharge from the hospital. These studies are summarized and assessed in this narrative review. Although exact estimates vary depending on the definitions used, the type of surgery, patient population, and risk factors (such as age), it is clear that PORD and other PPCs can be severe postoperative complications with significant associated mortality risks that extend weeks to months after discharge from the hospital.

Perioperative respiratory muscle exercise in patients undergoing cardiac surgery: An evidence-based review

BACKGROUND

Enhanced respiratory muscle management is imperative in cardiac surgery patients due to their universal risk of decreased perioperative respiratory muscle strength.

OBJECTIVES

Most existing articles primarily examine respiratory muscle exercise during either the preoperative, postoperative, or at-home phases. Consequently, there is a crucial need to consolidate the evidence for respiratory muscle exercise throughout the perioperative period of cardiac surgery.

METHODS

A literature search was performed, encompassing guideline networks and databases up until July 2023. The literature was classified into seven thematic categories: preoperative assessment, patient education, trainers, training plans, quality control, safety monitoring, and outcome assessment. The quality of the included literature was assessed using the GRAGE evidence grading system to ascertain the level of recommendation associated with each piece of evidence.

RESULTS

Nineteen papers were reviewed, encompassing 24 suggestions. These consisted of two suggestions on preoperative assessment, four on patient education, two on trainers, six on training programs, seven on quality control, two on safety monitoring, and one on outcome assessment. All 24 suggestions were categorized as strong recommendations, with 14 classified as high-quality evidence and ten as moderate-quality evidence.

CONCLUSIONS

Our study presents a succinct synthesis of the most robust evidence available on perioperative respiratory muscle exercise in cardiac surgery patients. We identified ten high-quality suggestions while an additional 14 moderate-quality suggestions. In the context of perioperative exercise, we recommend that moderate-intensity inspiratory muscle exercises be provided during the preoperative and postoperative phases upon transfer to the ward. We advocate for the implementation of low-intensity inspiratory muscle exercises during the postoperative phase while patients are in the intensive care unit.

Effect of Ultrasound-Guided Extra-Prevertebral Fascial Suprascapular Nerve and Infraclavicular Brachial Plexus Block on Postoperative Analgesia and Phrenic Nerve Function in Shoulder Arthroscopy: A Pilot Study

Purpose

The suprascapular nerve is situated between the prevertebral fascia and the superficial layer of deep cervical fascia and on the surface of the middle and posterior scalene muscles before it reaches the suprascapular notch. Consequently, we hypothesized that injecting local anesthetics (LAs) there would introduce a new block approach for blocking the suprascapular nerve, ie, extra-prevertebral fascial block. We assessed the postoperative analgesic effect, as well as the incidence of diaphragmatic paralysis 30 minutes after the block.

Methods

30 patients undergoing elective shoulder arthroscopic rotator cuff repair surgery were recruited in this study. Before the induction of general anesthesia, 15 mL of 0.5% ropivacaine was administered to perform an extra-prevertebral fascia suprascapular nerve block (10 mL) and an infraclavicular brachial plexus block (5 mL, primarily targeting the axillary nerve). All patients received intravenous patient-controlled analgesia (PCA) after surgery. The postoperative pain was scored with Numeric Rating Scale (NRS), along with the opioid consumption in the first 24 h after surgery. The incidence of hemi-diaphragmatic paralysis (HDP) was measured 30 minutes after the block.

Results

All patients received the successful block. The resting NRS pain scores at 1h, 6h, 12h, and 24h postoperatively were 0 [0, 2], 0 [0, 2], 1 [0, 2], and 2 [1, 3], respectively. The oral morphine equivalent (OME) consumption at 24 hours after surgery was 18 [12,30] mg. No patients experienced HDP (complete or partial) 30 minutes after the block.

Conclusion

Compared with the posterior approach, this novel technique is efficient and has a higher success rate of blockade. It eliminates the need for patients to change positions, thereby improving comfort. Additionally, when combined with the infraclavicular brachial plexus block, it can effectively block the suprascapular nerve, providing satisfactory postoperative analgesia without the HDP at 30min after blockade compared to the anterior approach.

Increased postoperative complications after laparoscopic gastrectomy in patients with preserved ratio impaired spirometry

BACKGROUND

Preserved ratio impaired spirometry (PRISm), defined as decreased forced expiratory volume in the first second in the setting of normal ratio, is associated with an increased risk of respiratory disease and systemic comorbidities. Unlike severe obstructive pulmonary disease, little is known about the impact of PRISm on short-term outcomes in patients undergoing laparoscopic gastrectomy (LG) and its association with small airway dysfunction (SAD).

METHODS

This study enrolled 830 patients who underwent preoperative spirometry and LG between January 2021 and August 2023. Of these, 228 patients were excluded. Participants were categorized into 3 groups based on their baseline lung function, and postoperative outcomes were subsequently analyzed. Potential associations between postoperative outcomes and various clinical variables were examined using univariate and multivariate analyses.

RESULTS

PRISm was identified in 16.6% of the patients, whereas SAD was present in 20.4%. The incidence of postoperative pulmonary complications (PPCs) was notably higher in the SAD group (20.3% vs 9.8%, P = .002) and the PRISm group (28.0% vs 9.8%, P < .001) than the normal group. Among the 3 groups, pneumonia was the most frequently observed PPC. Multivariate analysis revealed that both SAD (odds ratio [OR], 2.34; 95% CI, 1.30-4.22; P = .005) and PRISm (OR, 3.26; 95% CI, 1.80-5.90; P < .001) independently constituted significant risk factors associated with the occurrence of PPCs. Univariate analysis showed that female was a possible risk factor for PPCs in PRISm group.

CONCLUSION

Our study showed that PRISm and SAD were associated with the increased PPCs in patients undergoing LG for gastric cancer.

Effects of midline laparotomy on cough strength: a prospective study measuring cough pressure

BACKGROUND

Laparotomy is assumed to decrease cough strength due to three factors: abdominal muscle trauma, postoperative pain, and diaphragmatic dysfunction. However, the effect of trauma from laparotomy itself on strength (net of the other two factors) has not been measured to our knowledge. The aim of this study was to measure the effect of laparotomy on cough strength after first measuring the effect of epidural analgesia.

METHODS

In 11 patients scheduled for open midline laparotomy, cough pressure (PCOUGH), a proxy for strength, was measured with a rectal balloon at three moments: before the procedure, at baseline; before surgery, under epidural bupivacaine to T6; and postoperatively, under epidural bupivacaine to the same analgesic level (T6). Continuous variables were compared using the Wilcoxon signed-rank test. The repeatability of PCOUGH measurements was confirmed with the intraclass correlation coefficient (ICC). Pain on coughing, hand grip strength, and the Ramsay and modified Bromage scores were also recorded.

RESULTS

Median (interquartile range) PCOUGH decreased from a baseline of 103 (89-137) to 71 (56-116) cmH2O under presurgical epidural bupivacaine (P=0.003). Postoperative PCOUGH remained unchanged at 76 (46-85) cmH2O under epidural analgesia (P=0.131). The ICCs indicated excellent repeatability of the PCOUGH measurements (P<0.001). Pain on coughing was 0 to 1 in all subjects. Hand grip strength and the Ramsay and Bromage scores were unchanged.

CONCLUSIONS

Although thoracic epidural bupivacaine reduces cough strength as measured by PCOUGH, midline laparotomy does not further reduce strength in the presence of adequate epidural analgesia.

Effects of laryngeal mask ventilation on postoperative atelectasis in children undergoing day surgery: a randomized controlled trial

BACKGROUND

To compare the effects of laryngeal mask mechanical ventilation and preserved spontaneous breathing on postoperative atelectasis in children undergoing day surgery.

METHODS

Children aged 3-7 who underwent elective day surgery were randomly divided into a spontaneous breathing group (n = 23) and a mechanical ventilation group (n = 23). All children enrolled in this trial used the same anesthesia induction protocol, the incidence and severity of atelectasis before induction and after operation were collected. In addition, the baseline data, intraoperative vital signs, ventilator parameters and whether there were complications such as reflux and aspiration were also collected. SPSS was used to calculate whether there was a statistical difference between these indicators.

RESULTS

The incidence of atelectasis in the spontaneous breathing group was 91.30%, and 39.13% in the mechanical ventilation group, and the difference was statistically significant (P = 0.001). There was a statistically significant difference in carbon dioxide (P < 0.05), and the severity of postoperative atelectasis in the mechanical ventilation group was lower than that in the spontaneous breathing group (P < 0.05). In addition, there were no significant differences in the vital signs and baseline data of the patients (P > 0.05).

CONCLUSION

Laryngeal mask mechanical ventilation can reduce the incidence and severity of postoperative atelectasis in children undergoing day surgery, and we didn't encounter any complications such as reflux and aspiration in children during the perioperative period, so mechanical ventilation was recommended to be used for airway management.

TRIAL REGISTRATION

The clinical trial was registered retrospectively at the Chinese Clinical Trial Registry. ( https://www.chictr.org.cn . Registration number ChiCTR2300071396, Weiwei Cai, 15 May 2023).

Potential mechanisms of multimodal prehabilitation effects on surgical complications: a narrative review

Continuous advances in prehabilitation research over the past several decades have clarified its role in improving preoperative risk factors, yet the evidence demonstrating reduced surgical complications remains uncertain. Describing the potential mechanisms underlying prehabilitation and surgical complications represents an important opportunity to establish biological plausibility, develop targeted therapies, generate hypotheses for future research, and contribute to the rationale for implementation into the standard of care. In this narrative review, we discuss and synthesize the current evidence base for the biological plausibility of multimodal prehabilitation to reduce surgical complications. The goal of this review is to improve prehabilitation interventions and measurement by outlining biologically plausible mechanisms of benefit and generating hypotheses for future research. This is accomplished by synthesizing the available evidence for the mechanistic benefit of exercise, nutrition, and psychological interventions for reducing the incidence and severity of surgical complications reported by the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). This review was conducted and reported in accordance with a quality assessment scale for narrative reviews. Findings indicate that prehabilitation has biological plausibility to reduce all complications outlined by NSQIP. Mechanisms for prehabilitation to reduce surgical complications include anti-inflammation, enhanced innate immunity, and attenuation of sympathovagal imbalance. Mechanisms vary depending on the intervention protocol and baseline characteristics of the sample. This review highlights the need for more research in this space while proposing potential mechanisms to be included in future investigations.

Peri-operative Hemi-diaphragmatic Variations After Brachial Plexus Block Above the Clavicle: A Prospective Observational Study of the Contralateral Side

OBJECTIVE

Hemi-diaphragm palsy after brachial plexus block above the clavicle (BPBAC) occurs frequently, but few patients develop post-operative pulmonary complications (PPC). We hypothesized that contralateral hemidiaphragm function increases after BPBAC. This contralateral function preserves global diaphragmatic function, avoiding PPC in the case of ipsilateral hemi-diaphragm palsy.

METHODS

This prospective observational cohort study included 64 adult patients undergoing shoulder surgery with planned BPBAC (interscalene brachial plexus block and supraclavicular block). The Thickening Fraction (TF) was measured by ultrasound in both hemi-diaphragms, ipsilateral (TF _ipsilateral) and contralateral (TF_{contralateral}) to the BPBAC, before and after the surgery. TF_global is the sum of TF_ipsilateral and TF_{contralateral}. PPC were defined as occurrences of dyspnea, tachypnea, SpO₂ <90% or SpO₂/FiO₂ <315.

RESULTS

TF_{contralateral} increased significantly (an average of 40%) after BPBAC (p = 0.001), and TF_ipsilateral decreased (an average of 72%). After BPBAC, 86% of patients had a decreased TF_ipsilateral and 59% of patients an increased TF_{contralateral} at post-operatively. Only 17% of patients have PPC.

CONCLUSION

After BPBAC, global diaphragm function decreases because of ipsilateral hemi-diaphragm reduction, but less than expected because of increased contralateral hemi-diaphragm function. As a part of diaphragm function, contralateral hemi-diaphragm function must be checked.

Sugammadex Versus Neostigmine for Recovery of Respiratory Muscle Strength Measured by Ultrasonography in the Postextubation Period: A Randomized Controlled Trial

BACKGROUND

Although sugammadex is well known for its use in reducing the incidence of residual neuromuscular blockade, this has not always been translated to improved clinical measures of postoperative respiratory muscle strength. Expiratory muscles play an important role in airway clearance and inspiratory muscle capacity augmentation, yet they have not been well studied. Therefore, we tested the hypothesis on whether sugammadex could enhance expiratory muscle strength recovery more completely than neostigmine in the immediate postextubation period.

METHODS

Adult patients having microlaryngeal surgery under total intravenous anesthesia were randomized to receive sugammadex or neostigmine. The thickening fraction of internal oblique abdominal muscle (TF IO ) and diaphragm excursion, respectively, reflecting expiratory and inspiratory muscle strength, were measured via ultrasonography at 3 time points: before induction (baseline), train-of-four ratio (TOFR) recovery to 0.9, and 30 minutes after postanesthesia care unit (PACU) arrival. The primary outcome was the change in TF IO from baseline to TOFR ≥0.9. The postoperative changes of diaphragm excursion from baseline, incidences of TF IO and diaphragm excursion returning to baseline levels, and the time from TOFR 0.9 to 0.95 and 1 were also measured.

RESULTS

Among 58 patients, a significant difference in the change in TF IO from baseline to TOFR ≥0.9 between the sugammadex and neostigmine groups was observed: mean ± standard deviation, 9% ± 6% vs 16% ± 9%; difference in means: -6% (95% confidence interval [CI], -10 to -2); and adjusted P =.005 (adjusting for imbalanced variables between 2 groups). Sugammadex resulted in smaller changes in diaphragm excursion from baseline to TOFR ≥0.9 compared with neostigmine: difference in means: -0.83 cm (99.4% CI, -1.39 to -0.28 cm; Bonferroni-corrected P < .001). After 30 minutes in the postanesthesia care unit (PACU),33% of patients reversed with sugammadex versus 14% of those receiving neostigmine reached baseline TF IO levels (99.4% CI, -14 to 52; Bonferroni-corrected P > .999). The incidences of TF IO and diaphragm excursion returning to baseline were relatively low (<40%) in both groups despite TOFR reaching 1. The median time from TOFR of 0.9 to 0.95 and to 1 among patients receiving sugammadex was 7 and 10× faster than those receiving neostigmine (0.3 vs 2 minutes, Bonferroni-corrected P = .003; 0.5 vs 5.3 minutes, Bonferroni-corrected P < .001, respectively).

CONCLUSIONS

Sugammadex provides a more complete recovery of expiratory muscle strength than neostigmine at TOFR ≥0.9. Our data suggest that the respiratory muscle strength might still be impaired despite TOFR reaching 1.

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.

[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.

A review of upper airway physiology relevant to the delivery and deposition of inhalation aerosols

Developing effective oral inhaled drug delivery treatment strategies for respiratory diseases necessitates a thorough knowledge of the respiratory system physiology, such as the differences in the airway channel's structure and geometry in health and diseases, their surface properties, and mechanisms that maintain their patency. While respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma and their implications on the lower airways have been the core focus of most of the current research, the role of the upper airway in these diseases is less known, especially in the context of inhaled drug delivery. This is despite the fact that the upper airway is the passageway for inhaled drugs to be delivered to the lower airways, and their replicas are indispensable in current standards, such as the cascade impactor experiments for testing inhaled drug delivery technology. This review provides an overview of upper airway collapsibility and their mechanical properties, the effects of age and gender on upper airway geometry, and surface properties. The review also discusses how COPD and asthma affect the upper airway and the typical inhalation flow characteristics exhibited by the patients with these diseases.

Impact of intubated vs. non-intubated anesthesia on postoperative diaphragmatic function: Results from a prospective observational study

Background: An altered diaphragmatic function was associated with the development of postoperative pulmonary complications following thoracic surgery.

Methods: To evaluate the impact of different anesthetic techniques on postoperative diaphragmatic dysfunction, patients undergoing video-assisted thoracoscopic surgery (VATS) lung biopsy for interstitial lung disease were enrolled in a monocentric observational prospective study. Patients received intubated or non-intubated anesthesia according to risk assessment and preferences following multidisciplinary discussion. Ultrasound measured diaphragmatic excursion (DIA) and Thickening Fraction (TF) were recorded together with arterial blood gases and pulmonary function tests (PFT) immediately before and 12 h after surgery. Pain control and postoperative nausea and vomiting (PONV) were also evaluated.

Results: From February 2019 to September 2020, 41 consecutive patients were enrolled. Five were lost due to difficulties in collecting postoperative data. Of the remaining 36 patients, 25 underwent surgery with a non-intubated anesthesia approach whereas 11 underwent intubated general anesthesia. The two groups had similar baseline characteristics. On the operated side, DIA and TF showed a lower residual postoperative function in the intubated group compared to the non-intubated group (54 vs. 82% of DIA and 36 vs. 97% of TF; p = 0.001 for both). The same was observed on the non-operated side (58 vs. 82% and 62 vs. 94%; p = 0.005 and p = 0.045, respectively, for DIA and TF). No differences were observed between groups in terms of pain control, PONV, gas exchange and PFT.

Conclusion: This study suggests that maintenance of spontaneous breathing during VATS lung biopsy is associated with better diaphragmatic residual function after surgery.

Outcomes and risk factors for delayed-onset postoperative respiratory failure: a multi-center case-control study by the University of California Critical Care Research Collaborative (UC3RC)

BACKGROUND

Few interventions are known to reduce the incidence of respiratory failure that occurs following elective surgery (postoperative respiratory failure; PRF). We previously reported risk factors associated with PRF that occurs within the first 5 days after elective surgery (early PRF; E-PRF); however, PRF that occurs six or more days after elective surgery (late PRF; L-PRF) likely represents a different entity. We hypothesized that L-PRF would be associated with worse outcomes and different risk factors than E-PRF.

METHODS

This was a retrospective matched case-control study of 59,073 consecutive adult patients admitted for elective non-cardiac and non-pulmonary surgical procedures at one of five University of California academic medical centers between October 2012 and September 2015. We identified patients with L-PRF, confirmed by surgeon and intensivist subject matter expert review, and matched them 1:1 to patients who did not develop PRF (No-PRF) based on hospital, age, and surgical procedure. We then analyzed risk factors and outcomes associated with L-PRF compared to E-PRF and No-PRF.

RESULTS

Among 95 patients with L-PRF, 50.5% were female, 71.6% white, 27.4% Hispanic, and 53.7% Medicare recipients; the median age was 63 years (IQR 56, 70). Compared to 95 matched patients with No-PRF and 319 patients who developed E-PRF, L-PRF was associated with higher morbidity and mortality, longer hospital and intensive care unit length of stay, and increased costs. Compared to No-PRF, factors associated with L-PRF included: preexisiting neurologic disease (OR 4.36, 95% CI 1.81-10.46), anesthesia duration per hour (OR 1.22, 95% CI 1.04-1.44), and maximum intraoperative peak inspiratory pressure per cm H₂0 (OR 1.14, 95% CI 1.06-1.22).

CONCLUSIONS

We identified that pre-existing neurologic disease, longer duration of anesthesia, and greater maximum intraoperative peak inspiratory pressures were associated with respiratory failure that developed six or more days after elective surgery in adult patients (L-PRF). Interventions targeting these factors may be worthy of future evaluation.

Postoperative pulmonary complications and outcomes in cytoreductive surgery for ovarian cancer: a propensity-matched analysis

Objectives

To assess the prevalence of postoperative pulmonary complications (PPCs), the perioperative factors associated with PPCs, and the association of PPCs with postoperative outcomes in ovarian cancer patients undergoing cytoreductive surgery.

Methods

A retrospective analysis was conducted on patients who underwent cytoreductive surgery in our hospital, between September 2017 and January 2021, and patient medical records were reviewed to collect relevant clinical information. Univariable and multivariable analyses were used to identify significant risk factors for PPCs. Analysis of the association of PPCs with postoperative outcomes, mortality and 30-day readmission, was undertaken utilizing propensity score-matched controls and multivariable logistic regression model.

Results

Final analysis was performed with 268 ovarian cancer patients after cytoreductive surgery, among whom the incidence of PPCs was 26.9%, and the most frequent pulmonary complication was pleural effusion. According to the multivariate analysis, the intraoperative fluid infusion volume (L) (odds ratio (OR) 1.34; 95% confidence intervals (CI) 1.01–1.77; P = 0.040), diameter size of diaphragmatic resection (cm) (OR 1.16; 95% CI 1.06–1.28; P = 0.002), and surgical complexity scores (OR 1.26; 95% CI 1.13–1.42; P < 0.001) were significantly associated with the development of PPCs. The multivariable logistic regression analyses with propensity-matched controls demonstrated that the occurrence of PPCs significantly increased the risk of 30-day readmission (OR 6.01; 95% CI 1.12–32.40; P = 0.037) and did not significantly affect inpatient mortality.

Conclusion

Ovarian cancer patients undergoing cytoreductive surgery, especially those with diaphragmatic resection or higher surgical complexity scores, represent a high-risk population for PPCs. In addition, goal-directed fluid therapy is vital to reducing the occurrence of PPCs in patients at risk. PPCs were not associated with in-hospital mortality but were significantly associated with an increased risk of 30-day readmission after cytoreductive surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01660-2.

Frailty is an independent risk factor for postoperative pulmonary complications in elderly patients undergoing video-assisted thoracoscopic pulmonary resections

BACKGROUND

Although frailty as a common geriatric syndrome is associated with postoperative complications, its relationship with postoperative pulmonary complications (PPCs) following pulmonary resections in elderly patients is unclear.

AIMS

To investigate the relationship between frailty and PPCs in elderly patients undergoing video-assisted thoracoscopic pulmonary resections and explore the effect of the addition of frailty assessment to PPC risk index and ASA on their predictive ability.

METHODS

In a prospective cohort study, we measured frailty status using the FRAIL scale in elderly patients undergoing video-assisted thoracoscopic pulmonary resections. Multivariate analysis was used to identify the relationship between frailty and PPCs. Receiver operating characteristic curves were used to examine the predictive power of frailty and other assessment tools.

RESULTS

227 patients were analyzed in the study. The prevalence of PPCs was 24.7%. Significant differences between patients with and without PPCs were observed in the following aspects: BMI, smoking, COPD, respiratory infection within the last month, FEV1/FVC ratio, creatinine, ASA, frailty and PPC risk index (p < 0.05, respectively). After adjusting for all covariates, frailty was significantly related to PPCs in elderly patients (odds ratio: 6.33, 95% confidence interval: 2.45-16.37). Combined with frailty assessment, the area under the curve for ASA class and PPC risk index was increased to 0.759 (95% CI 0.687-0.831) and 0.821 (95% CI 0.758-0.883).

CONCLUSIONS

Frailty was associated with PPCs in elderly patients undergoing video-assisted thoracoscopic pulmonary resections. Combined with the frailty assessment, the predictive power of the PPC risk index and ASA class was improved.

Physiotherapy Regimens in Esophagectomy and Gastrectomy: a Systematic Review and Meta-Analysis

Background

Esophageal and gastric cancer surgery are associated with considerable morbidity, specifically postoperative pulmonary complications (PPCs), potentially accentuated by underlying challenges with malnutrition and cachexia affecting respiratory muscle mass. Physiotherapy regimens aim to increase the respiratory muscle strength and may prevent postoperative morbidity.

Objective

The aim of this study was to assess the impact of physiotherapy regimens in patients treated with esophagectomy or gastrectomy.

Methods

An electronic database search was performed in the MEDLINE, EMBASE, CENTRAL, CINAHL and Pedro databases. A meta-analysis was performed to assess the impact of physiotherapy on the functional capacity, incidence of PPCs and postoperative morbidity, in-hospital mortality rate, length of hospital stay (LOS) and health-related quality of life (HRQoL).

Results

Seven randomized controlled trials (RCTs) and seven cohort studies assessing prehabilitation totaling 960 patients, and five RCTs and five cohort studies assessing peri- or postoperative physiotherapy with 703 total patients, were included. Prehabilitation resulted in a lower incidence of postoperative pneumonia and morbidity (Clavien–Dindo score ≥ II). No difference was observed in functional exercise capacity and in-hospital mortality following prehabilitation. Meanwhile, peri- or postoperative rehabilitation resulted in a lower incidence of pneumonia, shorter LOS, and better HRQoL scores for dyspnea and physical functioning, while no differences were found for the QoL summary score, global health status, fatigue, and pain scores.

Conclusion

This meta-analysis suggests that implementing an exercise intervention may be beneficial in both the preoperative and peri- or postoperative periods. Further investigation is needed to understand the mechanism through which exercise interventions improve clinical outcomes and which patient subgroup will gain the maximal benefit.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-11122-7.

Spontaneous recovery of neuromuscular blockade is an independent risk factor for postoperative pulmonary complications after abdominal surgery: A secondary analysis

BACKGROUND

In intermediate-to-high-risk patients, major abdominal surgery is associated with a high incidence of postoperative complications, mainly pulmonary. Neuromuscular blocking drugs have been suggested as a contributing factor, but this remains unproven.

OBJECTIVE

To define the relationship of neuromuscular blockade management (reversal) with postoperative pulmonary complications (PPCs).

DESIGN

The individualised PeRioperative Open-lung approach Versus standard protectivE ventilation in abdominal surgery study was a prospective, multicentre, four-arm, randomised controlled trial. This is a secondary analysis of the data.

SETTING

Twenty-one teaching hospitals in Spain. The study was conducted between 2 January 2015, and 18 May 2016.

PATIENTS

Age more than 18 years with an intermediate-to-high risk for PPCs, scheduled for major abdominal surgery lasting more than 2 h. Exclusion criteria included pregnancy or breastfeeding, and moderate-to-severe organ diseases.

INTERVENTIONS

The mode of reversal of neuromuscular blockade determined two patient groups: pharmacological reversal versus spontaneous recovery.

MAIN OUTCOME MEASURES

The primary outcome was a composite of PPCs during the first 30 postoperative days. The association between categorical variables and PPCs within 30 days was studied. Univariate and multivariable logistic regression modelling and propensity score analyses were performed.

RESULTS

From the 923 patients included, 596 (64.6%) presented with PPCs within 30 days after surgery. Patients who developed these complications were older with a higher BMI, a lower pre-operative SpO2, a higher ASA physical status score and a higher incidence of arterial hypertension, diabetes mellitus or chronic obstructive pulmonary disease. Pharmacological neuromuscular blockade reversal was associated with a lower incidence of PPCs (odds ratio 0.62, 95% CI 0.47 to 0.82).

CONCLUSION

Spontaneous recovery of neuromuscular blockade was an independent risk factor for PPCs in patients with intermediate-to-high risk, undergoing abdominal surgery. We suggest this factor should be included in future studies on PPCs.

TRIAL REGISTRATION

clinicaltrials.gov identifier: NCT02158923.

Respiratory complications after surgery in Vietnam: National estimates of the economic burden

Background

Estimating the cost of postoperative respiratory complications is crucial in developing appropriate strategies to mitigate the global and national economic burden. However, systematic analysis of the economic burden in low- and middle-income countries is lacking.

Methods

We used the nationwide database of the Vietnam Social Insurance agency and extracted data from January 2017 to September 2018. The data contain 1 241 893 surgical patients undergoing one of seven types of surgery. Propensity score matching method was used to match cases with and without complications. We used generalized gamma regressions to estimate the direct medical costs; logistic regressions to evaluate the impact of postoperative respiratory complications on re-hospitalization and outpatient visits.

Findings

Postoperative respiratory complications increased the odds of re-hospitalization and outpatient visits by 3·49 times (95% CI: 3·35–3·64) and 1·39 times (95% CI: 1·34–1·45) among surgical patients, respectively. The mean incremental cost associated with postoperative respiratory complications occurring within 30 days of the index admission was 1053·3 USD (95% CI: 940·7–1165·8) per procedure, which was equivalent to 41% of the GDP per capita of Vietnam in 2018. We estimated the national annual incremental cost due to respiratory complications occurring within 30 days after surgery was 13·87 million USD. Pneumonia contributed the greatest part of the annual cost burden of postoperative respiratory complications.

Interpretation

The economic burden of postoperative respiratory complications is substantial at both individual and national levels. Postoperative respiratory complications also increase the odds of re-hospitalization and outpatient visits and increase the length of hospital stay among surgical patients.

Funding

The authors did not receive any funds for conducting this study

Adding autogenic drainage to chest physiotherapy after upper abdominal surgery: effect on blood gases and pulmonary complications prevention. Randomized controlled trial

BACKGROUND

Hypoxemia and pulmonary complications are common after upper abdominal surgery (UAS).

OBJECTIVE

To examine whether inclusion of autogenic drainage (AD) in chest physiotherapy after UAS confers additional benefits in improving blood gases and reducing postoperative pulmonary complications (PPCs).

DESIGN AND SETTING

Randomized controlled study conducted at Kasr Al-Ainy teaching hospital, Egypt.

METHODS

A randomized controlled trial was conducted on 48 subjects undergoing elective UAS with high risk of developing PPCs. The study group received AD plus routine chest physiotherapy (deep diaphragmatic breathing, localized breathing and splinted coughing) and the control group received routine chest physiotherapy only. The outcomes included arterial blood gases measured at the first and seventh postoperative days, incidence of PPCs within the first seven days and length of hospital stay.

RESULTS

Baseline characteristics were similar between groups. In the AD group, SaO2, PaO2, PaCO2 and HCO3 significantly improved (P < 0.05) while in the physiotherapy group, only SaO2 and PaO2 significantly improved (P < 0.05). Nonetheless, significant differences in post-treatment SaO2 and PaO2 between the groups were observed. The overall incidence of PPCs was 16.66% (12.5% in the AD group and 20.8% in the physiotherapy group) (absolute risk reduction -8.3%; 95% confidence interval, CI, -13.5 to 29.6%), with no significant difference between the groups. The AD group had a significantly shorter hospital stay (P = 0.0001).

CONCLUSION

Adding AD to routine chest physiotherapy after UAS provided a favorable blood gas outcome and reduced the length of hospital stay. It tended to reduce the incidence of PPCs.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04446520.

Identification of the Risk Factors of Postoperative Pulmonary Complications in Elderly Patients Undergoing Elective Colorectal Surgery

OBJECTIVE

This study was to identify the perioperative related risk factors of postoperative pulmonary complications (PPCs) in elderly patients undergoing elective colorectal surgery, which will provide new insight for better prevention and intervention of PPCs in elderly patients.

METHODS

A retrospective study involving 445 patients (age ≥65), who registered in Shengjing Hospital affiliated to China Medical University for elective colorectal surgery from October 2014 to March 2017, was conducted. Clinical data, including demographic information, medical history, preoperative examination, and surgery-related factors, were analyzed and compared between the patient group with PPCs and the group without PPCs. t-test or χ² test was performed for statistical analysis between the 2 groups. Binary logistic regression analysis was further employed to identify the potential independent risk factors of PPCs.

RESULTS

Among the 445 patients enrolled in the study, 49 (11%) had PPCs, while 396 (89%) did not. The main risk factors of PPC occurrence in the elderly patients undergoing elective colorectal surgery included older age (age ≥75 years), ASA >II, hypertension, myocardial ischemia, basic pulmonary diseases, laparotomy, blood transfusion, preoperative hemoglobin <100 g/L, and albumin <35 g/L. Laparotomy (compared with laparoscope) and ASA >II were independent risk factors for the increased incidence of PPCs.

CONCLUSION

More attention should be paid to patients with older age and ASA >II in elective colorectal surgery. Choice of laparoscopic operation, proper treatment of hypertension, myocardial ischemia, basic pulmonary diseases, and correction of anemia and nutritional status can effectively reduce the incidence of PPCs. An adequate and comprehensive evaluation of the potential risk factors related to PPCs is required before surgery.

Perioperative diaphragm point-of-care ultrasound as a prediction tool of postoperative respiratory failure in high-risk patients: A feasibility study and case series

INTRODUCTION

Respiratory muscle function in the postoperative period is a key to whether a patient develops Postoperative Respiratory Failure (PRF) or not. PRF occurs when the gas exchange does not meet metabolic needs. Ipsilateral paralysis of the hemidiaphragm after interscalenic brachial plexus block (ISB) causes an acute reduction of respiratory muscle function. This reduction does not cause PRF when the contralateral hemidiaphragm generates enough gas exchange to meet metabolic demands.

OBJECTIVES

To study the evolution of hemidiaphragmatic muscle function during the perioperative period with diaphragmatic ultrasound (D-POCUS), and use it as an innovative tool to predict PRF, assessing the contralateral hemidiaphragm in the event of acute hemidiaphragm paralysis.

METHODS

Patients considered high risk, scheduled for shoulder surgery with ISB are studied. Both hemidiaphragms were evaluated by ultrasound, before and after the procedure, measuring Thickening Fraction (TF) and Diaphragmatic Excursion (DE). PACU patients with PRF were registered.

RESULTS

There was a significant reduction in the TF and DE of the ipsilateral hemidiaphragm in the six patients studied. Only 1/6 patients showed signs of PRF. The evaluation of the contralateral hemidiaphragm during the postoperative period showed that in the five patients without signs of PRF, there were no significant changes in the function of the contralateral hemidiaphragm. The patient, who showed a reduction in contralateral hemidiaphragm function, was the only one who suffered PRF.

CONCLUSIONS

In this case series, D-POCUS allows to know the perioperative function of the diaphragm in high-risk patients. All patients suffered an acute reduction of hemidiaphragm function after ISB; however, these patients did not develop PRF when the contralateral hemidiaphragm function was preserved.

Ten years of the Helsinki Declaration on patient safety in anaesthesiology: An expert opinion on peri-operative safety aspects

: Patient safety is an activity to mitigate preventable patient harm that may occur during the delivery of medical care. The European Board of Anaesthesiology (EBA)/European Union of Medical Specialists had previously published safety recommendations on minimal monitoring and postanaesthesia care, but with the growing public and professional interest it was decided to produce a much more encompassing document. The EBA and the European Society of Anaesthesiology (ESA) published a consensus on what needs to be done/achieved for improvement of peri-operative patient safety. During the Euroanaesthesia meeting in Helsinki/Finland in 2010, this vision was presented to anaesthesiologists, patients, industry and others involved in health care as the 'Helsinki Declaration on Patient Safety in Anaesthesiology'. In May/June 2020, ESA and EBA are celebrating the 10th anniversary of the Helsinki Declaration on Patient Safety in Anaesthesiology; a good opportunity to look back and forward evaluating what was achieved in the recent 10 years, and what needs to be done in the upcoming years. The Patient Safety and Quality Committee (PSQC) of ESA invited experts in their fields to contribute, and these experts addressed their topic in different ways; there are classical, narrative reviews, more systematic reviews, political statements, personal opinions and also original data presentation. With this publication we hope to further stimulate implementation of the Helsinki Declaration on Patient Safety in Anaesthesiology, as well as initiating relevant research in the future.

Patient-ventilator asynchrony in conventional ventilation modes during short-term mechanical ventilation after cardiac surgery: randomized clinical trial

INTRODUCTION AND AIM

Studies regarding asynchrony in patients in the cardiac postoperative period are still only a few. The main objective of our study was to compare asynchronies incidence and its index (AI) in 3 different modes of ventilation (volume-controlled ventilation [VCV], pressure-controlled ventilation [PCV] and pressure-support ventilation [PSV]) after ICU admission for postoperative care.

METHODS

A prospective parallel randomised trialin the setting of a non-profitable hospital in Brazil. The participants were patients scheduled for cardiac surgery. Patients were randomly allocated to VCV or PCV modes of ventilation and later both groups were transitioned to PSV mode.

RESULTS

All data were recorded for 5 minutes in each of the three different phases: T1) in assisted breath, T2) initial spontaneous breath and T3) final spontaneous breath, a marking point prior to extubation. Asynchronies were detected and counted by visual inspection method by two independent investigators. Reliability, inter-rater agreement of asynchronies, asynchronies incidence, total and specific asynchrony indexes (AIt and AIspecific) and odds of AI ≥10% weighted by total asynchrony were analysed. A total of 17 patients randomly allocated to the VCV (n=9) or PCV (n=8) group completed the study. High inter-rated agreement for AIt (ICC 0.978; IC95%, 0,963-0.987) and good reliability (r=0.945; p<0.001) were found. Eighty-two % of patients presented asynchronies, although only 7% of their total breathing cycles were asynchronous. Early cycling and double triggering had the highest rates of asynchrony with no difference between groups. The highest odds of AI ≥10% were observed in VCV regardless the phase: OR 2.79 (1.36-5.73) in T1 vs T2, p=0.005; OR 2.61 (1.27-5.37) in T1 vs T3, p=0.009 and OR 4.99 (2.37-10.37) in T2 vs T3, p<0.001.

CONCLUSIONS

There was a high incidence of breathing asynchrony in postoperative cardiac patients, especially when initially ventilated in VCV. VCV group had a higher chance of AI ≥10% and this chance remained high in the following PSV phases.

Point of Care Ultrasound to Identify Diaphragmatic Dysfunction after Thoracic Surgery

BACKGROUND

Postoperative diaphragmatic dysfunction after thoracic surgery is underestimated due to the lack of reproducible bedside diagnostic methods. We used point of care ultrasound to assess diaphragmatic function bedside in patients undergoing video-assisted thoracoscopic or thoracotomic lung resection. Our main hypothesis was that the thoracoscopic approach may be associated with lower incidence of postoperative diaphragm dysfunction as compared to thoracotomy. Furthermore, we assessed the association between postoperative diaphragmatic dysfunction and postoperative pulmonary complications.

METHODS

This was a prospective observational cohort study. Two cohorts of patients were evaluated: those undergoing video-assisted thoracoscopic surgery versus those undergoing thoracotomy. Diaphragmatic dysfunction was defined as a diaphragmatic excursion less than 10 mm. The ultrasound evaluations were carried out before (preoperative) and after (i.e., 2 h and 24 h postoperatively) surgery. The occurrence of postoperative pulmonary complications was assessed up to 7 days after surgery.

RESULTS

Among the 75 patients enrolled, the incidence of postoperative diaphragmatic dysfunction at 24 h was higher in the thoracotomy group as compared to video-assisted thoracoscopic surgery group (29 of 35, 83% vs. 22 of 40, 55%, respectively; odds ratio = 3.95 [95% CI, 1.5 to 10.3]; P = 0.005). Patients with diaphragmatic dysfunction on the first day after surgery had higher percentage of postoperative pulmonary complications (odds ratio = 5.5 [95% CI, 1.9 to 16.3]; P = 0.001). Radiologically assessed atelectasis was 46% (16 of 35) in the thoracotomy group versus 13% (5 of 40) in the video-assisted thoracoscopic surgery group (P = 0.040). Univariate logistic regression analysis indicated postoperative diaphragmatic dysfunction as a risk factor for postoperative pulmonary complications (odds ratio = 5.5 [95% CI, 1.9 to 16.3]; P = 0.002).

CONCLUSIONS

Point of care ultrasound can be used to evaluate postoperative diaphragmatic function. On the first postoperative day, diaphragmatic dysfunction was less common after video-assisted than after the thoracotomic surgery and is associated with postoperative pulmonary complications.

Preoperative intervention with long-acting bronchodilators for the reduction of postoperative pulmonary complications in untreated patients with obstructive lung disease

BACKGROUND

Obstructive lung disease (OLD) is a risk factor for postoperative pulmonary complications (PPC) and is incidentally discovered during preoperative evaluation. The key treatments for OLD are inhaled long-acting bronchodilators (LAB). However, the advantage of preoperative bronchodilator treatment for patients with OLD remains unclear. The aim of this study is to elucidate the effect of preoperative LAB treatment in patients with untreated OLD on postoperative outcomes.

METHODS

In this propensity-matched cohort study, we included patients who were referred to the pulmonologists for untreated OLD. The patients were either treated with LAB or left untreated. The primary outcome was the incidence of prolonged oxygen therapy (>3 days) in the postoperative period. We evaluated patients' characteristics with and without the use of LAB using propensity score (PS) matching weight. Subsequently, the outcomes in the two groups were compared.

RESULTS

We analysed 614 patients; 132 patients were part of the LAB group and 482 were included in the control group. In the crude analysis, the incidence of prolonged oxygen therapy was higher in the LAB group than in the control group (odds ratio [OR] = 1.35; P = 0.04). However, after PS matching weight, no statistically significant differences in prolonged oxygen therapy (OR = 1.15), incidence of prolonged intensive care unit stay, endotracheal re-intubation postoperatively and in-hospital death between the groups were identified.

CONCLUSION

There is a limited benefit of preoperative treatment with inhaled LAB for the reduction of PPC in patients with untreated OLD.

Insights into postoperative respiration by using continuous wireless monitoring of respiratory rate on the postoperative ward: a cohort study

Change of respiratory rate (RespR) is the most powerful predictor of clinical deterioration. Brady- (RespR ≤ 8) and tachypnea (RespR ≥ 31) are associated with serious adverse events. Simultaneously, RespR is the least accurately measured vital parameter. We investigated the feasibility of continuously measuring RespR on the ward using wireless monitoring equipment, without impeding mobilization. Continuous monitoring of vital parameters using a wireless SensiumVitals® patch was installed and RespR was measured every 2 mins. We defined feasibility of adequate RespR monitoring if the system reports valid RespR measurements in at least 50% of time-points in more than 80% of patients during day- and night-time, respectively. Data from 119 patients were analysed. The patch detected in 171,151 of 227,587 measurements valid data for RespR (75.2%). During postoperative day and night four, the system still registered 68% and 78% valid measurements, respectively. 88% of the patients had more than 67% of valid RespR measurements. The RespR’s most frequently measured were 13–15; median RespR was 15 (mean 16, 25th- and 75th percentile 13 and 19). No serious complications or side effects were observed. We successfully measured electronically RespR on a surgical ward in postoperative patients continuously for up to 4 days post-operatively using a wireless monitoring system. While previous studies mentioned a digit preference of 18–22 for RespR, the most frequently measured RespR were 13–16. However, in the present study we did not validate the measurements against a reference method. Rather, we attempted to demonstrate the feasibility of achieving continuous wireless measurement in patients on surgical postoperative wards. As the technology used is based on impedance pneumography, obstructive apnoea might have been missed, namely in those patients receiving opioids post-operatively.

Effects of Opioids Given to Facilitate Mechanical Ventilation on Sleep Apnea After Extubation in the Intensive Care Unit

Study Objectives

Following extubation in the intensive care unit (ICU), upper airway (UA) edema and respiratory depressants may promote UA dysfunction. We tested the hypothesis that opioids increase the risk of sleep apnea early after extubation.

Methods

Fifty-six ICU patients underwent polysomnography the night after extubation. Airflow limitation during wakefulness was identified using bedside spirometry. Correlation and ordinal regression analyses were used to quantify the effects of preextubation opioid dose on postextubation apnea-hypopnea index (AHI) and severity of sleep apnea and whether or not inspiratory airway obstruction (ratio of maximum expiratory and inspiratory airflows at 50% of vital capacity [MEF50/MIF50] ≥ 1) during wakefulness predicts airway obstruction during sleep. Data were adjusted for age, gender, body mass index, as well as a generalized propensity score balanced for APACHE II, score for preoperative prediction of obstructive sleep apnea, duration of mechanical ventilation, chronic obstructive pulmonary disease, and a procedural severity score for morbidity.

Results

Sleep apnea (AHI ≥ 5) was present in 40 (71%) of the 56 patients. Morphine equivalent dose given 24 hours prior extubation predicted obstructive respiratory events during sleep (r = 0.35, p = .01) and sleep apnea (odds ratio [OR] 1.17; 95% confidence interval [CI] 1.02-1.34). Signs of inspiratory UA obstruction (MEF50/MIF50 ≥ 1) assessed by bedside spirometry were strongly associated with sleep apnea (OR 5.93; 95% CI 1.16-30.33).

Conclusions

High opioid dose given 24 hours prior to extubation increases the likelihood of postextubation sleep apnea in the ICU, particularly in patients with anatomical vulnerability following extubation.

Pain management in neurocritical care; an update

PURPOSE OF REVIEW

Pain management in neurocritical care is a subject often avoided because of concerns over the side-effects of analgesics and the potential to cause additional neurological injury with treatment. The sedation and hypercapnia caused by opioids have been feared to mask the neurological examination and contribute to elevations in intracranial pressure. Nevertheless, increasing attention to patient satisfaction has sparked a resurgence in pain management. As opioids have remained at the core of analgesic therapy, the increasing attention to pain has contributed to a growing epidemic of opioid dependence. In this review, we summarize the most recent literature regarding opioids and their alternatives in the treatment of acute pain in patients receiving neurocritical care.

RECENT FINDINGS

Studies on pain management in neurocritical care continue to explore nonopioid analgesics as part of a multimodal strategy aimed at decreasing overall opioid consumption. Agents including local anesthetics, acetaminophen, ketamine, gabapentinoids, and dexmedetomidine continue to demonstrate efficacy. In addition, the prolonged longitudinal course of many recent trials has also revealed more about the transition from acute to chronic pain following hospitalization.

SUMMARY

In an era of increasing attention to patient satisfaction mitigated by growing concerns over the harms imposed by opioids, alternative analgesic therapies are being investigated with promising results.

Obstructive sleep apnoea in adults: peri-operative considerations: A narrative review

: Obstructive sleep apnoea (OSA) is a common breathing disorder of sleep with a prevalence increasing in parallel with the worldwide rise in obesity. Alterations in sleep duration and architecture, hypersomnolence, abnormal gas exchange and also associated comorbidities may all feature in affected patients.The peri-operative period poses a special challenge for surgical patients with OSA who are often undiagnosed, and are at an increased risk for complications including pulmonary and cardiovascular, during that time. In order to ensure the best peri-operative management, anaesthetists caring for these patients should have a thorough understanding of the disorder, and be aware of the individual's peri-operative risk constellation, which depends on the severity and phenotype of OSA, the invasiveness of the surgical procedure, anaesthesia and also the requirement for postoperative opioids.The objective of this review is to educate clinicians in the epidemiology, pathogenesis and diagnosis of OSA in adults and also to highlight specific tasks in the preoperative assessment, namely to select a suitable intra-operative anaesthesia regimen, and manage the extent and duration of postoperative care to facilitate the best peri-operative outcome.

Recent advances in understanding and managing postoperative respiratory problems

Postoperative respiratory complications increase healthcare utilization (e.g. hospital length of stay, unplanned admission to intensive care or high-dependency units, and hospital readmission), mortality, and adverse discharge to a nursing home. Furthermore, they are associated with significant costs. Center-specific treatment guidelines may reduce risks and can be guided by a local champion with multidisciplinary involvement. Patients should be risk-stratified before surgery and offered anesthetic choices (such as regional anesthesia). It is established that laparoscopic surgery improves respiratory outcomes over open surgery but requires tailored anesthesia/ventilation strategies (positive end-expiratory pressure utilization and low inflation pressure). Interventions to optimize treatment include judicious use of intensive care, moderately restrictive fluid therapy, and appropriate neuromuscular blockade with adequate reversal. Patients’ ventilatory drive should be kept within a normal range wherever possible. High-dose opioids should be avoided, while volatile anesthetics appear to be lung protective. Tracheal extubation should occur in the reverse Trendelenburg position, and postoperative continuous positive airway pressure helps prevent airway collapse. In combination, all of these interventions facilitate early mobilization.

Comparisons and correlations of pain intensity and respiratory and peripheral muscle strength in the pre- and postoperative periods of cardiac surgery

OBJECTIVE

To evaluate respiratory and peripheral muscle strength after cardiac surgery. Additionally, we compared the changes in these variables on the third and sixth postoperative days.

METHODS

Forty-six patients were recruited, including 17 women and 29 men, with a mean age of 60.50 years (SD = 9.20). Myocardial revascularization surgery was performed in 36 patients, replacement of the aortic valve in 5 patients, and replacement of the mitral valve in 5 patients.

RESULTS

A significant reduction in respiratory and peripheral muscle strength and a significant increase in pain intensity were observed on the third and sixth postoperative days (p < 0.05), except for the variable maximal inspiratory pressure; on the sixth postoperative day, maximal inspiratory pressure values were already similar to the preoperative and predicted values (p > 0.05). There was an association between peripheral muscle strength, specifically between maximal expiratory pressure preoperatively (rs = 0.383; p = 0.009), on the third postoperative day (rs = 0.468; p = 0.001) and on the sixth postoperative day (rs = 0.311; p = 0.037). The effect sizes were consistently moderate-to-large for respiratory muscle strength, the Medical Research Council scale and the visual analog scale, in particular between preoperative assessment and the sixth postoperative day.

CONCLUSION

There is a decrease in respiratory and peripheral muscle strength after cardiac surgery. In addition, maximal expiratory pressure is the variable that is most associated with peripheral muscle strength. These variables, especially respiratory and peripheral muscle strength, should be considered by professionals working in the intensive care setting.

Magnesium sulphate improves pulmonary function after video-assisted thoracoscopic surgery: A randomised double-blind placebo-controlled study

BACKGROUND

Reduced lung volumes are unavoidable after lung resection surgery. Magnesium sulphate (MgSO4) administration has been reported to reduce the requirement for neuromuscular blocking drugs and postoperative analgesics in surgical patients.

OBJECTIVE

To investigate the effect of MgSO4 on pulmonary function after video-assisted thoracoscopic surgery (VATS).

DESIGN

A randomised, double-blind, placebo-controlled trial.

SETTING

A university tertiary care centre.

PATIENTS

Sixty-six patients scheduled for pulmonary lobectomy or segmentectomy via VATS.

INTERVENTION

Patients were allocated to one of two groups: the Mg (MgSO4 50 mg kg intravenously for 10 min, followed by a continuous infusion of 15 mg kg h during surgery) or the control (same volume of 0.9% saline).

MAIN OUTCOME MEASURES

Pulmonary function tests [forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and peak expiratory flow rate] were measured before surgery and at three time points after surgery (2, 24 and 48 h postoperatively) using a portable spirometer. Twelve months after surgery, pulmonary function test values were repeated at a regular outpatient follow-up visit.

RESULTS

FEV1 at 24 (1.7 ± 0.6 vs. 1.3 ± 0.5 l, P = 0.033) and 48 h (1.7 ± 0.6 vs. 1.4 ± 0.5 l, P = 0.021) and FVC at 24 (2.0 ± 0.8 vs. 1.6 ± 0.6 l, P = 0.038) and 48 h (2.2 ± 0.8 vs. 1.7 ± 0.7 l, P = 0.008) after surgery were significantly greater in the Mg group. Patients in the Mg group required less rocuronium than those in the control group (64.2 ± 19.9 vs. 74.9 ± 20.3 mg, respectively; P = 0.041). Consumption of postoperative patient-controlled analgesia was also significantly less at 24 and 48 h after surgery in the Mg group (P = 0.022 and 0.015, respectively), although pain scores and rescue analgesics were comparable. Five patients in the control group were diagnosed with postoperative pneumonia using clinical and radiological criteria before discharge. FEV1 and FVC at 12 months after surgery were not different between the two groups.

CONCLUSION

Intraoperative administration of MgSO4 improved pulmonary function and reduced the need for rocuronium and postoperative analgesics in patients who underwent VATS.

TRIAL REGISTRATION

cris.nih.go.kr identifier: KCT0001410.

Prolonged mechanical ventilation worsens sepsis-induced diaphragmatic dysfunction in the rat

Background

Short-term mechanical ventilation (MV) protects against sepsis-induced diaphragmatic dysfunction. Prolonged MV induces diaphragmatic dysfunction in non-septic animals, but few reports describe the effects of prolonged MV in sepsis. We hypothesized that prolonged MV is not protective but worsens the diaphragmatic dysfunction induced by a mild sepsis, because MV and sepsis share key signaling mechanisms, such as cytokine upregulation.

Method

We studied the impact of prolonged MV (12 h) in four groups (n = 8) of male Wistar rats: 1) endotoxemia induced by intraperitoneal injection of Escherichia coli lipopolysaccharide, 2) MV without endotoxemia, 3) combination of endotoxemia and MV and 4) sham control. Diaphragm mechanical performance, pro-inflammatory cytokine concentrations (Tumor Necrosis Factor-α, Interleukin-1β, Interleukin-6) in plasma were measured.

Results

Prolonged MV and sepsis independtly reduced maximum diaphragm force (-27%, P = 0.003; -37%, P<0.001; respectively). MV and sepsis acted additively to further decrease diaphragm force (-62%, P<0.001). Similar results were observed for diaphragm kinetics (maximum lengthening velocity -47%, P<0.001). Sepsis and MV reduced diaphragm cross sectional area of type I and IIx fibers, which was further increased by the combination of sepsis and MV (all P<0.05). Sepsis and MV were individually associated with the presence of a robust perimysial inflammatory infiltrate, which was more marked when sepsis and MV were both present (all P<0.05). Sepsis and, to a lesser extent, MV increased proinflammatory cytokine production in plasma and diaphragm (all P<0.05); proinflammatory cytokine expression in plasma was increased further by the combination of sepsis and MV (all P<0.05). Maximum diaphragm force correlated negatively with plasma and diaphragmatic cytokine production (all p<0.05).

Conclusions

Prolonged (12 h) MV exacerbated sepsis-induced decrease in diaphragm performance. Systemic and diaphragmatic overproduction of pro-inflammatory cytokines may contribute to diaphragm weakness.

Prevention of respiratory complications of the surgical patient: actionable plan for continued process improvement

PURPOSE OF REVIEW

Postoperative respiratory complications (PRCs) increase hospitalization time, 30-day mortality and costs by up to $35 000. These outcomes measures have gained prominence as bundled payments have become more common.

RECENT FINDINGS

Results of recent quantitative effectiveness studies and clinical trials provide a framework that helps develop center-specific treatment guidelines, tailored to minimize the risk of PRCs. The implementation of those protocols should be guided by a local, respected, and visible facilitator who leads proper implementation while inviting center-specific input from surgeons, anesthesiologists, and other perioperative stakeholders.

SUMMARY

Preoperatively, patients should be risk-stratified for PRCs to individualize intraoperative choices and postoperative pathways. Laparoscopic compared with open surgery improves respiratory outcomes. High-risk patients should be treated by experienced providers based on locally developed bundle-interventions to optimize intraoperative treatment and ICU bed utilization. Intraoperatively, lung-protective ventilation (procedure-specific positive end-expiratory pressure utilization, and low driving pressure) and moderately restrictive fluid therapy should be used. To achieve surgical relaxation, high-dose neuromuscular blocking agents (and reversal agents) as well as high-dose opioids should be avoided; inhaled anesthetics improve surgical conditions while protecting the lungs. Patients should be extubated in reverse Trendelenburg position. Postoperatively, continuous positive airway pressure helps prevent airway collapse and protocolized, early mobilization improves cognitive and respiratory function.

Regional Anesthesia With Noninvasive Ventilation for Shoulder Surgery in a Patient With Severe Chronic Obstructive Pulmonary Disease: A Case Report

Interscalene block (ISB) impairs ipsilateral lung function and generally is not used for patients with respiratory insufficiency. We present a 49-year-old man with chronic obstructive pulmonary disease scheduled for shoulder surgery. He was given a regional technique with an ISB (short-acting local anesthetic to minimize duration of diaphragmatic dysfunction) and suprascapular and axillary nerves blocks (long-acting local anesthetic). He was supported with noninvasive ventilation during the time of hemidiaphragmatic paralysis as documented by serial ultrasound examination. A discussion about ISB and its alternatives (general anesthesia versus brachial plexus block versus selective peripheral nerve blocks) always should occur for patients at risk for pulmonary complications.

Continuous Positive Airway Pressure Mitigates Opioid-induced Worsening of Sleep-disordered Breathing Early after Bariatric Surgery

BACKGROUND

Bariatric surgery patients are vulnerable to sleep-disordered breathing (SDB) early after recovery from surgery and anesthesia. The authors hypothesized that continuous positive airway pressure (CPAP) improves postoperative oxygenation and SDB and mitigates opioid-induced respiratory depression.

METHODS

In a randomized crossover trial, patients after bariatric surgery received 30% oxygen in the postanesthesia care unit (PACU) under two conditions: atmospheric pressure and CPAP (8 to 10 cm H2O). During 1 h of each treatment, breathing across cortical arousal states was analyzed using polysomnography and spirometry. Arousal state and respiratory events were scored in accordance with American Academy of Sleep Medicine guidelines. Data on opioid boluses in the PACU were collected. The primary and secondary outcomes were the apnea hypopnea index (AHI) and apnea after self-administration of opioids in the PACU. Linear mixed model analysis was used to compare physiologic measures of breathing.

RESULTS

Sixty-four percent of the 33 patients with complete postoperative polysomnography data demonstrated SDB (AHI greater than 5/h) early after recovery from anesthesia. CPAP treatment decreased AHI (8 ± 2/h vs. 25 ± 5/h, P < 0.001), decreased oxygen desaturations (5 ± 10/h vs. 16 ± 20/h, P < 0.001), and increased the mean oxygen saturation by 3% (P = 0.003). CPAP significantly decreased the respiratory-depressant effects observed during wakefulness-sleep transitions without affecting hemodynamics. The interaction effects between CPAP treatment and opioid dose for the dependent variables AHI (P < 0.001), inspiratory flow (P = 0.002), and minute ventilation (P = 0.015) were significant.

CONCLUSIONS

This pharmacophysiologic interaction trial shows that supervised CPAP treatment early after surgery improves SDB and ameliorates the respiratory-depressant effects of opioids without undue hemodynamic effects.

Development and validation of a Score for Preoperative Prediction of Obstructive Sleep Apnea (SPOSA) and its perioperative outcomes

BACKGROUND

Postoperative respiratory complications (PRCs) are associated with significant morbidity, mortality, and hospital costs. Obstructive sleep apnea (OSA), often undiagnosed in the surgical population, may be a contributing factor. Thus, we aimed to develop and validate a score for preoperative prediction of OSA (SPOSA) based on data available in electronic medical records preoperatively.

METHODS

OSA was defined as the occurrence of an OSA diagnostic code preceded by a polysomnography procedure. A priori defined variables were analyzed by multivariable logistic regression analysis to develop our score. Score validity was assessed by investigating the score's ability to predict non-invasive ventilation. We then assessed the effect of high OSA risk, as defined by SPOSA, on PRCs within seven postoperative days and in-hospital mortality.

RESULTS

A total of 108,781 surgical patients at Partners HealthCare hospitals (2007-2014) were studied. Predictors of OSA included BMI >25 kg*m^-2 and comorbidities, including pulmonary hypertension, hypertension, and diabetes. The score yielded an area under the curve of 0.82. Non-invasive ventilation was significantly associated with high OSA risk (OR 1.44, 95% CI 1.22-1.69). Using a dichotomized endpoint, 26,968 (24.8%) patients were identified as high risk for OSA and 7.9% of these patients experienced PRCs. OSA risk was significantly associated with PRCs (OR 1.30, 95% CI 1.19-1.43).

CONCLUSION

SPOSA identifies patients at high risk for OSA using electronic medical record-derived data. High risk of OSA is associated with the occurrence of PRCs.

Diaphragmatic function is enhanced in fatty and diabetic fatty rats

Background

Obesity is associated with a decrease in mortality in the intensive care unit (ICU) (the "obesity paradox"). We hypothesized that obesity may paradoxically improve diaphragmatic function.

Methods

Diaphragm contractility was prospectively recorded in vitro in adult male Zucker lean (control), fatty, and diabetic fatty rats, at rest, after 12h mechanical ventilation and after fatigue. We analyzed diaphragm morphology, cytokines, and protein expression of the protein kinase signaling pathways.

Results

Diaphragm active-force (AF) was higher in fatty (96±7mN.mm^-2,P = 0.02) but not in diabetic fatty rats (90±17mN.mm^-2) when compared with controls (84±8mN.mm^-2). Recovery from fatigue was improved in fatty and diabetic fatty groups compared with controls. Ventilator-induced diaphragmatic dysfunction was observed in each group, but AF remained higher in fatty (82±8mN.mm^-2,P = 0.03) compared with controls (70±8mN.mm^-2). There was neutral lipid droplet accumulation in fatty and diabetic fatty. There were shifts towards a higher cross-sectional-area (CSA) of myosin heavy chain isoforms (MyHC)-2A fibers in fatty and diabetic fatty compared with control rats (P = 0.002 and P<0.001, respectively) and a smaller CSA of MyHC-2X in fatty compared with diabetic fatty and control rats (P<0.001 and P<0.001, respectively). The phosphorylated total-protein-kinase-B (pAKT)/AKT ratio was higher in fatty (182±58%,P = 0.03), but not in diabetic fatty when compared with controls and monocarboxylate-transporter-1 was higher in diabetic fatty (147±36%,P = 0.04), but not in fatty.

Conclusions

Diaphragmatic force is increased in Zucker obese rats before and after mechanical ventilation, and is associated with activation of AKT pathway signaling and complex changes in morphology.