Intraoperative ventilation strategies for obese patients undergoing bariatric surgery: systematic review and meta-analysis

Abstract

Background: Obesity is a global epidemic, and it is widely known that increased Body mass index (BMI) is associated with alterations in respiratory mechanics. Bariatric surgery is established as an effective treatment for this condition. Objective: To assess the safety and effectiveness of different ventilation strategies in obese patients undergoing bariatric surgery. Methods: A systematic review of randomized clinical trials aimed at evaluating ventilation strategies for obese patients was carried out. Primary outcomes: in-hospital mortality, adequacy of gas exchange, and respiration mechanics alterations. Results: Fourteen clinical trials with 574 participants were included. When recruitment maneuvers (RM) vs Positive endexpiratory pressure (PEEP) were compared, RM resulted in better oxygenation p = 0.03 (MD 79.93), higher plateau pressure p < 0.00001 (MD 7.30), higher mean airway pressure p < 0.00001 (MD 6.61), and higher compliance p < 0.00001 (MD 21.00); when comparing RM + Zero end-expiratory pressure (ZEEP) vs RM + PEEP 5 or 10 cmH2O, RM associated with PEEP led to better oxygenation p = 0.001 (MD 167.00); when comparing Continuous Positive Airway Pressure (CPAP) 40 cmH2O + PEEP 10 cmH2O vs CPAP 40 cmH2O + PEEP 15 cmH2O, CPAP 40 + PEEP 15 achieved better gas exchange p = 0.003 (MD 36.00) and compliance p = 0.0003 (MD 3.00). Conclusion: There is some evidence that the alveolar recruitment maneuvers associated with PEEP lead to better oxygenation and higher compliance. There is no evidence of differences between pressure control ventilation (PCV) and Volume control ventilation (VCV).

Anesthetic Management of a Super Morbidly Obese Obstetric Patient With a Body Mass Index of 109 kg/m2 Presenting for Her Fourth Caesarean Delivery

“…Managing intraoperative ventilation and preparing the patient for safe extubation required specific planning. We applied low tidal volume ventilation based on her ideal body weight along with periodic recruitment maneuvers and positive end-expiratory pressure, which have been shown to reduce atelectasis and improve oxygenation and lung compliance in obese patients [15][16][17]. This open lung concept is also implicated in preventing the development of ventilator-induced lung injury by stabilizing the alveoli.…”

Comparison of Intra-operative Pressure-Controlled Ventilation and Volume-Controlled Ventilation in Bariatric Surgery: A Prospective Randomized Study

“…It allows a high initial flow rate, faster alveolar inflation, and, consequently, a more homogeneous distribution of the delivered gas mixture and better ventilationperfusion matching besides the reduced risk of volutraumas and barotraumas [1,11,12]. Although improved oxygenation through the use of intra-operative PCV rather than volume-controlled ventilation (VCV) has been reported in some studies, there is as yet no data suggesting the benefits of intra-operative PCV or VCV in terms of clinical outcomes among obese patients [9,[13][14][15][16]]. Given the lack of clear evidence on the most effective intra-operative ventilation strategy in this specific patient population, the present study has been designed to compare the use of intra-operative PCV and VCV in obese patients undergoing laparoscopic bariatric surgery in terms of peripheral tissue oxygenation (PTO), respiratory functions, and hemodynamic status and post-operative mechanical complications [9].…”

“…Although different intra-operative ventilation strategies have been evaluated in several studies, the ideal ventilation strategy for obese patients undergoing surgery has yet to be defined [ 9 , 10 ]. Pressure-controlled ventilation (PCV) decelerates the inspiratory flow.…”

“…It allows a high initial flow rate, faster alveolar inflation, and, consequently, a more homogeneous distribution of the delivered gas mixture and better ventilation-perfusion matching besides the reduced risk of volutraumas and barotraumas [ 1 , 11 , 12 ]. Although improved oxygenation through the use of intra-operative PCV rather than volume-controlled ventilation (VCV) has been reported in some studies, there is as yet no data suggesting the benefits of intra-operative PCV or VCV in terms of clinical outcomes among obese patients [ 9 , 13 - 16 ].…”

“…Given the lack of clear evidence on the most effective intra-operative ventilation strategy in this specific patient population, the present study has been designed to compare the use of intra-operative PCV and VCV in obese patients undergoing laparoscopic bariatric surgery in terms of peripheral tissue oxygenation (PTO), respiratory functions, and hemodynamic status and post-operative mechanical complications [ 9 ].…”