Lung recruitment prevents collapse during laparoscopy in children A randomised controlled trial

BACKGROUND Capnoperitoneum and anaesthesia impair lung aeration during laparoscopy in children. These changes can be detected and monitored at the bedside by lung ultrasound (LUS). OBJECTIVE The aim of our study was to assess the impact of general anaesthesia and capnoperitoneum on lung collapse and the potential preventive effect of lung recruitment manoeuvres, using LUS in children undergoing laparoscopy. DESIGN Randomised controlled study. SETTING Single-institution study, community hospital, Mar del Plata, Argentina. PATIENTS Forty-two children American Society of Anesthesiologists I-II aged 6 months to 7 years undergoing laparoscopy. INTERVENTIONS All patients were studied using LUS before, during and after capnoperitoneum. Children were allocated to a control group (C-group, n=21) receiving standard protective ventilation, or to a lung recruitment manoeuvre group (RM-group) (n=21), in which lung recruitment manoeuvres were performed after recording baseline LUS images before capnoperitoneum. Loss of aeration was scored by summing a progressive grading from 0 to 3 assigned to each of 12 lung areas, based on the detection of four main ultrasound patterns: normal aeration - 0, partial loss-mild - 1, partial loss-severe 2, total lossconsolidation - 3. MAIN OUTCOME MEASURES Lung aeration score and atelectasis assessed by ultrasound. RESULTS Before capnoperitoneum and recruitment manoeuvres in the treated group the two groups presented similar ultrasound scores (5.95 +/- 4.13 vs. 5.19 +/- 3.33, P= 0.5). In the RM-group, lung aeration significantly improved both during (2.71 +/- 2.47) and after capnoperitoneum (2.52 +/- 2.86), compared with the C-group (6.71 +/- 3.54, P<0.001, and 8.48 +/- 3.22, P<0.001, respectively). There was no statistically significant difference in the percentage of atelectasis before capnoperitoneum and recruitment manoeuvres in the RM-group (62%) and in the C-group (47%, P= 0.750). However, during capnoperitoneum, only 19% of the RM-group had atelectasis compared with 80% in the C-group (P< 0.001). CONCLUSION The majority of children undergoing laparoscopy have anaesthesia-induced atelectasis. In most cases, lung collapse due to capnoperitoneum could have been prevented by recruitment manoeuvres followed by positive-end expiratory pressure.