Lung aeration changes after lung recruitment in children with acute lung injury: A feasibility study

Abstract

Summary Rationale There are several adult studies using computed tomography (CT-scan) to examine lung aeration changes during or after a recruitment maneuver (RM) in ventilated patients with acute lung injury (ALI). However, there are no published data on the lung aeration changes during or after a RM in ventilated pediatric patients with ALI. Objective To describe CT-scan lung aeration changes and gas exchange after lung recruitment in pediatric ALI and assess the safety of transporting patients in the acute phase of ALI to the CT-scanner. Methods We present a case series completed in a subset of six patients enrolled in our previously published study of efficacy and safety of lung recruitment in pediatric patients with ALI. Intervention RM using incremental positive end-expiratory pressure. Results There was a variable increase in aerated and poorly aerated lung after the RM ranging from 3% to 72% (median 20%; interquartile range 6, 47; P = 0.03). All patients had improvement in the ratio of partial pressure of arterial oxygen over fraction of inspired oxygen (PaO2/FiO2) after the RM (median 14%; interquartile range: 8, 72; P = 0.03). There was a decrease in the partial pressure of arterial carbon dioxide (PaCO2) in four of six subjects after the RM (median −5%; interquartile range: −9, 2; P = 0.5). One subject had transient hypercapnia (41% increase in PaCO2) during the RM and this correlated with the smallest increase (3%) in aerated and poorly aerated lung. All patients tolerated the RM without hemodynamic compromise, barotrauma, hypoxemia, or dysrhythmias. Conclusions Lung recruitment results in improved lung aeration as detected by lung tomography. This is accompanied by improvements in oxygenation and ventilation. However, the clinical significance of these findings is uncertain. Transporting patients in early ALI to the CT-scanner seems safe and feasible.

Paediatric lung recruitment: a review of the clinical evidence

“…15 Further subgroup analysis on the ALI population from this study demonstrated an improvement in EEL and P/F ratio post recruitment as well as a significant reduction in PIP. 16 A study by Duff and colleagues in children with varied respiratory status demonstrated a significant and sustained reduction in FiO 2 requirement for up to 6 hours post a SI manoeuvre. 17 Another study using SI as a means to recruit lungs in combination with a stepwise recruitment manoeuvre reversed substantial atelectasis in dependant regions of the lung as measured by Electrical Impedance Tomography (EIT) which was also associated with improvements in gas exchange.…”

“…36 Boriosi and colleagues also found no significant change in compliance. [15][16] However, Marcus and colleagues found a 30% increase in dynamic pulmonary compliance using Ventrak software post their TRIM manouvre (p <0.01). 13 …”

“…Ultimately they used a modified version but found that oxygenation improved and peak inspiratory pressures were significantly reduced by 17% up to 12 hours post recruitment. 15,16 Incremental increase in both Peak Inspiratory Pressure (PIP) and PEEP has been shown to result in improved gas exchange, tidal volume (V t ), EELV, oxygenation and lung compliance in ventilated adults. [31][32][33][34] Sustained inflations (SI) or inspiratory holds recruit alveoli via a combination of factors -the plateau pressure achieved and the duration of time maintained at that pressure.…”

“…Boriosi and colleagues noted a P/F ratio increase of 53% (p< .01) in children post lung recruitment that was sustained for up to 12 hours. [15][16] Duff and colleagues found a reduced oxygen demand for up to 6 hours post a sustained inflation lung recruitment manoeuvre. 17 In adults several studies have demonstrated a beneficial effect on oxygenation assuming adequate baseline PEEP is present.…”

What's to Be Learned From 10 Patients in One Pediatric ICU?

“…6,7 Multiple studies have demonstrated short-term recruitment maneuver benefits in lung inflation, oxygenation, ventilation, and lung compliance, but data for longerterm benefit are lacking. [8][9][10] Indeed, there is no evidence that recruitment maneuvers improve survival.…”