Prevention of atelectasis by continuous positive airway pressure in anaesthetised children: A randomised controlled study

Abstract

Background: Continuous positive airway pressure (CPAP) prevents peri-operative atelectasis in adults, but its effect in children has not been quantified.

Objective: The aim of this study was to evaluate the role of CPAP in preventing postinduction and postoperative atelectasis in children under general anaesthesia.

Design: A randomised controlled study.

Setting: Single-institution study, community hospital, Mar del Plata. Argentina.

Patients: We studied 42 children, aged 6 months to 7 years, American Society of Anesthesiologists physical status class I, under standardised general anaesthesia.

Interventions: Patients were randomised into two groups: Control group (n = 21): induction and emergence of anaesthesia without CPAP; and CPAP group (n = 21): 5 cmH2O of CPAP during induction and emergence of anaesthesia. Lung ultrasound (LUS) imaging was performed before and 5 min after anaesthesia induction. Children without atelectasis were ventilated in the same manner as the Control group with standard ventilatory settings including 5 cmH2O of PEEP. Children with atelectasis received a recruitment manoeuvre followed by standard ventilation with 8 cmH2O of PEEP. Then, at the end of surgery, LUS images were repeated before tracheal extubation and 60 min after awakening.

Main outcome measures: Lung aeration score and atelectasis assessed by LUS.

Results: Before anaesthesia, all children were free of atelectasis. After induction, 95% in the Control group developed atelectasis compared with 52% of patients in the CPAP group (P < 0.0001). LUS aeration scores were higher (impaired aeration) in the Control group than the CPAP group (8.8 ± 3.8 vs. 3.5 ± 3.3 points; P < 0.0001). At the end of surgery, before tracheal extubation, atelectasis was observed in 100% of children in the Control and 29% of the CPAP group (P < 0.0001) with a corresponding aeration score of 9.6 ± 3.2 and 1.8 ± 2.3, respectively (P < 0.0001). After surgery, 30% of children in the Control group and 10% in the CPAP group presented with residual atelectasis (P < 0.0001) also corresponding to a higher aeration score in the Control group (2.5 ± 3.1) when compared with the CPAP group (0.5 ± 1.5; P < 0.01).

Conclusion: The use of 5 cmH2O of CPAP in healthy children of the studied age span during induction and emergence of anaesthesia effectively prevents atelectasis, with benefits maintained during the first postoperative hour.

Trial registry: Clinicaltrials.gov NCT03461770.