Artificial ventilation during pneumoperitoneum

Abstract

the complications pertaining to pneumoperitoneum to solve them quickly, paying particular attention to the patients at higher risk, such as elderly, obese, and those with cardiopulmonary disease. KEY WORDS: pneumoperitoneum, artificial ventilation, obesity, laparoscopy, anesthesia. IntroductionLaparoscopic surgery has been increasingly employed in various surgical subspecialties because of its innumerous benefits. These are evident during the post-operative period and result from the less important organ/tissue trauma caused by laparoscopic approaches than those triggered by open surgery. The main advantages of laparoscopic surgery are: reduction of the inflammatory and metabolic responses (1-3), reduced post-operative pain and analgesic consumption (2, 3), smaller incidence of respiratory complications (2), faster resolution of post-operative ileum and recovery (1). Taken together, these outcomes reduce hospital stay, promote a quicker return to normal daily activities (2-4), and reduce the cost of the treatment (4). On the other hand, laparoscopic surgery presents some challenges regarding the intra-operative anesthesia management, since there are respiratory and hemodynamic changes pertaining to the general anesthesia itself, to the abdominal insufflation, and to the intra-operative positioning of the patient (5). These issues become even more evident in patients with cardiopulmonary disease or obesity (6). This review focuses on the intra-operative respiratory alterations caused by laparoscopy and on the ventilatory strategies that are prone to minimize the modifications evoked by the technique. Alterations of the respiratory systemIn order to allow an adequate observation of the surgical field, laparoscopic surgery requires controlled gas insufflation into the peritoneal cavity (pneumoperitoneum). For this purpose, carbon dioxide is regularly used under a pressure of 10-15 mmHg. Naturally, respiratory issues related to mechanics and CO2 overload SummaryLaparoscopic surgery has been increasingly used in many surgical subspecialties, due to its various post-operative benefits. On the other hand, it presents intra-operative challenges to the anesthesia management. The inflation of the abdominal cavity with carbon dioxide leads to hemodynamic changes, mechanical respiratory system derangements (increased elastance, resistance and airway pressure), augmented V'CO2, and alterations of the V'/Q' ratio and of the PaCO2-PetCO2 gradient. All these changes may be influenced by other factors, such as body position and baseline characteristics of the patient. To minimize the negative consequences of these modifications a protective ventilation strategy with the use of low tidal volumes and PEEP, eventually associated with recruitment maneuvers, is suggested. No ventilatory mode or anesthetic drug has been proven better than the others. It has been suggested that the use of supraglotic devices may be a safe alternative to endotracheal intubation during laparoscopic surgery. It is important that the anesthetist be aware ...