Complications of the Alveolar Opening Maneuver in Children on Mechanical Ventilation

Objective

To analyze the overall incidence of complications associated with alveolar opening maneuvers and PEEP in pediatric patients with respiratory distress syndrome.

Materials and Methods

Study setting A prospective cohort study will be conducted between April and September in the Pediatric Intensive Care Unit (PICU) of the Hospital Cuenca Alta Néstor Kirchner (HCANK).

Sample All patients meeting the eligibility criteria will be included. An estimated total of 143 maneuvers involving alveolar opening maneuversand PEEP are to be analyzed, as these procedures are part of the standard care in managing ventilated patients with ARDS and are included in the institutional protocol (see Appendix).

Inclusion criteria

• Patients under 14 years of age admitted to the HCANK PICU
• More than 4 hours of invasive mechanical ventilation (IMV)
• An oxygenation index (OI) ≥4 or an oxygen saturation index (OSI) ≥5
• Indication for alveolar opening maneuvers and PEEP as determined by the treating team

Exclusion criteria

• Predicted body weight (PBW) >45.5 kg
• Recent pulmonary resection surgery (<7 days)
• Presence of broncho-pleural fistula or peri-tube leak >25% of the tidal volume
• Hemoglobin decline <7 g/dL
• Patients with congenital or acquired heart diseases with significant intracardiac shunt

Variables:

Outcome variable:

• Overall incidence of complications related to alveolar opening maneuvers and PEEP

Procedure Once patients are included, demographic, clinical, and relevant background data will be recorded in a dedicated data sheet. Following this, study evaluators will record baseline clinical data from the multiparameter monitor prior to performing the alveolar opening maneuvers and PEEP procedures. Relevant values will be obtained from the advanced monitoring sheet completed by the treating team.

During the alveolar opening maneuvers and PEEP procedures, intra-procedural complications will be noted, and monitoring will continue for 4 hours after the procedure to observe for any complications that develop.

If, due to intercurrences or the treating team's decision, the alveolar opening maneuvers and PEEP need to be repeated before 4 hours, monitoring will still continue for 4 hours after the last maneuver.

Statistical Analysis Categorical variables will be described using absolute numbers and percentages of the total, while continuous variables will be expressed using measures of central tendency and dispersion or position, depending on their distribution.

The Kolmogorov-Smirnov test will be used as a goodness-of-fit test to determine the distribution of numerical variables.

To address the objective, the overall incidence of complications will be calculated, with estimates and 95% confidence intervals provided.

Data analysis will be performed using IBM SPSS Windows version 25.0 (IBM Corp., Armonk, NY, USA), R version 3.6.3 (R Core Team, 2020), and the ggplot2 package version 3.3.2 (Wickham, 2016) for graph creation.

Sample size calculation The calculation assumes a null hypothesis where the incidence of complications after alveolar opening maneuvers and PEEP is 5%, based on previously reported data indicating a lower rate of complications.

The alternative hypothesis posits that the incidence of complications related to alveolar opening maneuvers and PEEP is less than 5%.

A total of 143 maneuvers are planned to be recruited according to the sample size calculation based on these hypothesized values.

Inclusion criteria

• Patients under 14 years of age admitted to the HCANK PICU
• More than 4 hours of invasive mechanical ventilation (IMV)
• An oxygenation index (OI) ≥4 or an oxygen saturation index (OSI) ≥5
• Indication for ARM and PEEP as determined by the treating team

Exclusion criteria

• Predicted body weight (PBW) >45.5 kg
• Recent pulmonary resection surgery (<7 days)
• Presence of broncho-pleural fistula or peri-tube leak >25% of the tidal volume
• Hemoglobin decline <7 g/dL
• Patients with congenital or acquired heart diseases with significant intracardiac shunt.