Congenital diaphragmatic hernia: Observed/expected lung-to-head ratio as a predictor of long-term morbidity

Abstract

Aim: The aim of this study was to investigate the association of observed/expected (O/E) lung-to-head ratio (LHR) with long-term morbidity for isolated fetal congenital diaphragmatic hernia (CDH) patients in a single institution.

Methods: We performed a retrospective study of prenatally diagnosed CDH from 18 to 38weeks of gestation (01/2002-04/2010). Two cohorts of O/E LHR were defined (22.6-45%, 45.1-78.3%) based upon previous studies. Survivors with at least 1-year follow-up of prospectively collected long-term morbidity assessments were included.

Results: O/E LHR was available in 43 survivors (median 40%, range 22.8-78.3%). Follow-up data were available in 41 survivors (M:F=24:17, left CDH=39/41). Median follow-up was 6.5years (1-11years). Height/weight trajectories were similar between the two cohorts, with the majority below the 50th centile. There were no differences between the two cohorts by age 3years for Bayley scales (developmental domains) and/or REEL-3 (language development). In addition, V/Q scans in the two cohorts demonstrated similar degrees of mismatch (mean delta V/Q=35.4 versus 31.3).

Conclusions: In fetuses with isolated CDH, a reduction in O/E LHR does not predict a worse outcome in long-term follow-up. There is no association between a lower O/E LHR and a reduction in REEL-3 or Bayley score nor V/Q mismatch.

Keywords: Congenital diaphragmatic hernia (CDH); Lung-to-head ratio (LHR); Morbidity; Outcome; Prognosis.