Effects of Pneumoperitoneum on Dynamic Alveolar Stress-strain in Anesthetized Pediatric Patients

General anesthesia is associated with loss of pulmonary functional residual capacity and consequent developement of atelectasis and closure of the small airway. Infants and young children are more susceptible to this lung collapse due to their small functional residual capacity. Mechanical ventilation in a lung with reduced functional residual capacity and atelectasis increased the dynamic alveolar stress-strain inducing a local inflammatory response in atelectatic lungs areas know as ventilatory induced-lung injury (VILI). This phenomenon may appear even in healthy patients undergoing general anesthesia and predisposes children to hypoxemic episodes that can persist in the early postoperative period. During laparoscopy, pneumoperitoneum may aggravate the reduction of functional residual capacity as it generates a further increase in intra-abdominal pressure. The increase in alveolar stress-strain cloud be reduced during pneumoperitoneum in theory, if normal functional residual capacity is restored and the transpulmonary pression is reached at the end of expiration of 0-1 cmH2O.