Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (VT) size was 500 ml, or 7 to 9 ml kg1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P < 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P < 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high VT and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome

Incidence of mortality and morbidity related to postoperative lung injury in patients who have undergone abdominal or thoracic surgery: A systematic review and meta-analysis

Background Lung injury is a serious complication of surgery. We did a systematic review and meta-analysis to assess whether incidence, morbidity, and in-hospital mortality associated with postoperative lung injury are affected by type of surgery and whether outcomes are dependent on type of ventilation. Methods We searched MEDLINE, CINAHL, Web of Science, and Cochrane Central Register of Controlled Trials for observational studies and randomised controlled trials published up to April, 2014, comparing lung-protective mechanical ventilation with conventional mechanical ventilation during abdominal or thoracic surgery in adults. Individual patients' data were assessed. Attributable mortality was calculated by subtracting the in-hospital mortality of patients without postoperative lung injury from that of patients with postoperative lung injury. Findings We identified 12 investigations involving 3365 patients. The total incidence of postoperative lung injury was similar for abdominal and thoracic surgery (3\ub74% vs 4\ub73%, p=0\ub7198). Patients who developed postoperative lung injury were older, had higher American Society of Anesthesiology scores and prevalence of sepsis or pneumonia, more frequently had received blood transfusions during surgery, and received ventilation with higher tidal volumes, lower positive end-expiratory pressure levels, or both, than patients who did not. Patients with postoperative lung injury spent longer in intensive care (8\ub70 [SD 12\ub74] vs 1\ub71 [3\ub77] days, p<0\ub70001) and hospital (20\ub79 [18\ub71] vs 14\ub77 [14\ub73] days, p<0\ub70001) and had higher in-hospital mortality (20\ub73% vs 1\ub74% p<0\ub70001) than those without injury. Overall attributable mortality for postoperative lung injury was 19% (95% CI 18\u201419), and differed significantly between abdominal and thoracic surgery patients (12\ub72%, 95% CI 12\ub70\u201412\ub76 vs 26\ub75%, 26\ub72\u201427\ub70, p=0\ub70008). The risk of in-hospital mortality was independent of ventilation strategy (adjusted HR 0\ub771, 95% CI 0\ub741\u20141\ub722). Interpretation Postoperative lung injury is associated with increases in in-hospital mortality and durations of stay in intensive care and hospital. Attributable mortality due to postoperative lung injury is higher after thoracic surgery than after abdominal surgery. Lung-protective mechanical ventilation strategies reduce incidence of postoperative lung injury but does not improve mortality

Incidence of mortality and morbidity related to postoperative lung injury in patients who have undergone abdominal or thoracic surgery: a systematic review and meta-analysis.

BACKGROUND: Lung injury is a serious complication of surgery. We did a systematic review and meta-analysis to assess whether incidence, morbidity, and in-hospital mortality associated with postoperative lung injury are affected by type of surgery and whether outcomes are dependent on type of ventilation. METHODS: We searched MEDLINE, CINAHL, Web of Science, and Cochrane Central Register of Controlled Trials for observational studies and randomised controlled trials published up to April, 2014, comparing lung-protective mechanical ventilation with conventional mechanical ventilation during abdominal or thoracic surgery in adults. Individual patients' data were assessed. Attributable mortality was calculated by subtracting the in-hospital mortality of patients without postoperative lung injury from that of patients with postoperative lung injury. FINDINGS: We identified 12 investigations involving 3365 patients. The total incidence of postoperative lung injury was similar for abdominal and thoracic surgery (3\ub74% vs 4\ub73%, p=0\ub7198). Patients who developed postoperative lung injury were older, had higher American Society of Anesthesiology scores and prevalence of sepsis or pneumonia, more frequently had received blood transfusions during surgery, and received ventilation with higher tidal volumes, lower positive end-expiratory pressure levels, or both, than patients who did not. Patients with postoperative lung injury spent longer in intensive care (8\ub70 [SD 12\ub74] vs 1\ub71 [3\ub77] days, p&lt;0\ub70001) and hospital (20\ub79 [18\ub71] vs 14\ub77 [14\ub73] days, p&lt;0\ub70001) and had higher in-hospital mortality (20\ub73% vs 1\ub74% p&lt;0\ub70001) than those without injury. Overall attributable mortality for postoperative lung injury was 19% (95% CI 18-19), and differed significantly between abdominal and thoracic surgery patients (12\ub72%, 95% CI 12\ub70-12\ub76 vs 26\ub75%, 26\ub72-27\ub70, p=0\ub70008). The risk of in-hospital mortality was independent of ventilation strategy (adjusted HR 0\ub771, 95% CI 0\ub741-1\ub722). INTERPRETATION: Postoperative lung injury is associated with increases in in-hospital mortality and durations of stay in intensive care and hospital. Attributable mortality due to postoperative lung injury is higher after thoracic surgery than after abdominal surgery. Lung-protective mechanical ventilation strategies reduce incidence of postoperative lung injury but does not improve mortality. FUNDING: None

The Association of Intraoperative driving pressure with postoperative pulmonary complications in open versus closed abdominal surgery patients - a posthoc propensity score-weighted cohort analysis of the LAS VEGAS study

BackgroundIt is uncertain whether the association of the intraoperative driving pressure (Delta P) with postoperative pulmonary complications (PPCs) depends on the surgical approach during abdominal surgery. Our primary objective was to determine and compare the association of time-weighted average Delta P (Delta P-TW) with PPCs. We also tested the association of Delta P-TW with intraoperative adverse events.MethodsPosthoc retrospective propensity score-weighted cohort analysis of patients undergoing open or closed abdominal surgery in the 'Local ASsessment of Ventilatory management during General Anaesthesia for Surgery' (LAS VEGAS) study, that included patients in 146 hospitals across 29 countries. The primary endpoint was a composite of PPCs. The secondary endpoint was a composite of intraoperative adverse events.ResultsThe analysis included 1128 and 906 patients undergoing open or closed abdominal surgery, respectively. The PPC rate was 5%. Delta P was lower in open abdominal surgery patients, but Delta P-TW was not different between groups. The association of Delta P-TW with PPCs was significant in both groups and had a higher risk ratio in closed compared to open abdominal surgery patients (1.11 [95%CI 1.10 to 1.20], P &lt; 0.001 versus 1.05 [95%CI 1.05 to 1.05], P &lt; 0.001; risk difference 0.05 [95%CI 0.04 to 0.06], P &lt; 0.001). The association of &lt;Delta&gt;P-TW with intraoperative adverse events was also significant in both groups but had higher odds ratio in closed compared to open abdominal surgery patients (1.13 [95%CI 1.12- to 1.14], P &lt; 0.001 versus 1.07 [95%CI 1.05 to 1.10], P &lt; 0.001; risk difference 0.05 [95%CI 0.030.07], P &lt; 0.001).Conclusions&lt;Delta&gt;P is associated with PPC and intraoperative adverse events in abdominal surgery, both in open and closed abdominal surgery.Trial registrationLAS VEGAS was registered at clinicaltrials.gov (trial identifier NCT01601223)