# Effects of lung protective ventilation and conventional ventilation on postoperative atelectasis in neonates under general anesthesia

## TL;DR

This study finds that lung protective ventilation reduces postoperative atelectasis in neonates under general anesthesia compared to conventional ventilation.

## Contribution

The study provides evidence that lung protective ventilation is effective in reducing atelectasis in neonates, a population where prior evidence was limited.

## Key findings

- LPV significantly reduced the incidence of significant postoperative atelectasis in neonates (18% vs. 58%).
- LPV resulted in lower median lung ultrasound scores compared to conventional ventilation.

## Abstract

General anesthesia frequently causes atelectasis, a condition that significantly endangers patient safety during and after surgery, especially in neonates. Evidence suggests that lung protective ventilation (LPV) strategies may reduce the incidence of postoperative atelectasis in patients receiving general anaesthesia; however, the efficacy for neonatal patients remains controversial. This study aims to explore how LPV affects the incidence of atelectasis in neonates.

This randomized controlled trial involved neonatal patients under general anesthesia with mechanical ventilation for over two hours, randomly assigned to receive LPV (including a Vt of 6 mL/kg, 5 cmH2O PEEP, and lung RMs once per hour) or conventional ventilation (including a Vt of 8–10 mL/kg without PEEP or RMs). Each infant underwent two lung ultrasound (LUS) scans at specified time points: 5 min post-intubation and at the conclusion of surgery. Additionally, three arterial blood gas analyses were conducted for each infant at T1 (5 min post-intubation), T2 (one hour after mechanical ventilation), and T3 (two hours after mechanical ventilation). HR and MAP were recorded at four time points: T1, T2, T3, and T4 (at the conclusion of surgery). The primary outcomes were the incidence of significant atelectasis (defined as any area with a consolidation score of ≥2) and LUS scores at the conclusion of surgery.

The study enrolled 100 neonatal patients, divided into 50 in the LPV group and 50 in the control group. At the conclusion of surgery, the LPV group had a significantly lower incidence of significant atelectasis (18% vs. 58%) and lower median LUS scores [7 [6, 9] vs. 12 [8, 18]] than the control group did (all P < 0.001). In addition, there were differences in the partial pressure of arterial oxygen (PaO₂) and partial pressure of arterial carbon dioxide (PaCO₂) between the two groups at T2 and T3, although both were within the normal range. No significant differences were observed in HR, MAP or the rate of respiratory events after surgery between the two groups.

Compared with conventional ventilation, LPV results in a significantly lower incidence of significant postoperative atelectasis and lower LUS scores in neonates receiving general anaesthesia.

ClinicalTrials.gov, ChiCTR2100051721