The Role of Lung Ultrasound in Optimizing Postextubation Respiratory Strategy in Children After Corrective Cardiac Surgery

Background: Children undergoing corrective cardiac surgery with cardiopulmonary bypass may experience impaired respiratory function postoperatively. Lung ultrasound (LU) can effectively detect subclinical fluid overload and provide real-time assessment of extravascular lung water at the bedside. This may inform the post-extubation strategy regarding the use of non-invasive respiratory support. The aim of our study was to assess the practicability and reliability of LU in predicting the need for respiratory support after extubation.

Methods: We performed a prospective, observational single-center study from January 2023 until August 2024 including patients under 1 year of age who had undergone corrective cardiac surgery and required mechanical ventilation for more than 24 hours. LU was conducted prior to extubation by two experienced sonographers on the anterior and lateral sides of the thorax, covering three scan areas for each hemithorax. Scores from 0 to 3 were assigned for each scanning area based on the presence and degree of A-lines and/or B-lines. Finally, patients were divided into two groups: Group 1 – Uncomplicated Recovery, defined as no need of respiratory support or non-invasive respiratory support for less than 3 days with no escalation required; and Group 2 – Complicated Recovery, defined as extended non-invasive respiratory support beyond 3 days or escalation of respiratory support within 48 hours after extubation.

Results: We included 34 children in the study, with a median age of 116 days (IQR: 24–163) and a median weight of 4.61 kg (IQR: 3.87–5.55). Groups 1 and 2 consisted of 23 and 11 children, respectively. Both groups showed comparable length of mechanical ventilation (3 days, IQR: 1–11 versus 4 days, IQR: 3–9; p = 0.31) and CPB time (114 minutes, IQR: 76–178 versus 128 minutes, IQR: 113–142; p = 0.38). Patients in Group 2 exhibited a statistically significantly higher lung ultrasound score compared with those in Group 1 (5, IQR: 3–7 versus 3, IQR: 1–4; p = 0.034).

Conclusion: Children with higher LU scores may require extended non-invasive respiratory support or escalation of respiratory support after extubation. Based on our experience, the practicability and reliability of LU was favorable in informing the post-extubation strategy related to the use of non-invasive respiratory support. However, further investigations are required to assess the potential of this method in clinical settings.

Publication History

Article published online:
11 February 2025