Effect of airway pressure release ventilation on mortality in pediatric severe acute respiratory distress syndrome - A retrospective comparative analysis

Abstract

Background : Acute respiratory distress syndrome (ARDS) in pediatric ICU contribute to up to 75% mortality which can be up to 90% in high risk patients. Despite of much advance in different ventilation strategies mortality remains unacceptably high. This suggests the need to define the role of newer management approaches. Airway pressure release ventilation (APRV) mode is a new strategy which looks promising in ARDS as shown in studies conducted on animals and adult patients. But its benefit has not been defined in pediatric patients with severe ARDS. Methods : This research was a retrospective comparative study using data from case files. The study period (Jan 2009 to December 2015) covered three years before the initiation of use of APRV mode to three years after its implementation. The study sample included all consecutive patients with ARDS in PICU of a tertiary care hospital during the study period. Patients admitted during APRV use period received APRV after failure of routine modes of ventilation(treatment group/APRV group) and patients admitted during pre-APRV use period received and continued on other modes of ventilation (control group/Non-APRV group). As the patients in treatment group naturally had severe ARDS; we included only severe ARDS cases in control group (equal in number to treatment group) to justify comparison. Case files were reviewed and data were recorded in terms of mortality, length of ICU stay, PaO2/FiO2 (PF) Ratio, lung injury score (LIS), PELOD score and demography. These were compared in two groups based on who received versus who did not receive APRV mode. Results : A total of 24 children in each group were analysed. Baseline PELOD score, age and gender distribution were comparable in both groups. PF Ratio were 67.21±9.74 in APRV versus 91.65(8.68) in non-APRV group (p value 0.01). Improvement in PF ratio after implication of APRV was statistically significant (mean difference of 14.36; p value=0.001). Duration of PF ratio 999], p value of 0.001. The covariates which were significantly associated with mortality were baseline PF ratio and PELOD scores. Conclusion : Use of APRV mode in pediatric severe ARDS used as rescue treatment achieved improved oxygenation and was associated with lower in hospital mortality.