3.5 Cardiac surgery
Seventy-seven percent of children with DS included in the analysis had a history of congenital cardiac disease and forty-five percent of the cohort (n=20) had previous cardiac surgery. NIV data were compared between those with a past history of cardiac surgery prior to NIV initiation and those without (Figure 4).
Those with a history of cardiac surgery showed significantly less NIV use, across all parameters. In terms of percentage of days used, those with prior cardiac surgery showed 71.18 ± 3.73% days used compared to 85.04 ± 2.68% in their non-surgical counterparts (p<0.001). As well as increased days used, the non-surgical cohort showed greater use per night, with a significantly greater percentage of days used >4hrs (62.07 ± 3.72% versus 49.83 ± 4.56, p=0.037) and increased average use per night (5.59 ± 0.34hrs versus 4.47 ± 0.40hrs, p=0.036).
Significantly greater AHI was observed in the cardiothoracic surgical cohort relative to their counterparts, 6.86 ± 0.93 and 4.75 ± 0.42 (p=0.031), respectively. However, despite poorer use the surgical cohort showed significantly greater system efficacy in the form of reduced system leak (p=0.046) and percentage of time at excess leak (p=0.004) relative to their non-surgical comparators.