Risk factors for in-hospital shunt thrombosis and mortality in patients weighing less than 3 kg with functionally univentricular heart undergoing a modified Blalock-Taussig shunt.

Abstract

To determine the association between several perioperative variables and in-hospital shunt thrombosis and mortality in patients weighing less than 3 kg with functional univentricular heart (UVH) who underwent modified Blalock-Taussig shunt. Between January 2006 and February 2016, 85 patients who weighed less than 3 kg with functional UVH and underwent modified Blalock-Taussig shunt were reviewed. In-hospital shunt thrombosis and mortality were the primary outcomes. The associations between perioperative variables and outcomes were assessed with univariate and multivariate analyses. In-hospital shunt thrombosis was 14% (12 of 85). Hospital mortality was 18% (15 of 85), which resulted in an 82% discharge survival rate. Shunt thrombosis was significantly associated with in-hospital mortality (odds ratio 18.9, 95% confidence interval 4.5-78.9). There were no statistically significant associations between weight, specific diagnosis of functional UVH and shunt thrombosis or mortality. Multivariate analysis identified delayed initiation of anticoagulant (P < 0.01) and postoperative cardiac arrest (P < 0.01) as risk factors of shunt thrombosis, while intraoperative bradycardia (P < 0.01), high postoperative haemoglobin (P = 0.03) and shunt thrombosis (P < 0.01) were risk factors for hospital mortality. In this high-risk group of patients who weighed less than 3 kg with functional UVH and who underwent modified Blalock-Taussig shunt, in-hospital mortality was strongly associated with the occurrence of shunt thrombosis. Our study highlighted the perioperative variables of delayed postoperative initiation of anticoagulant, cardiac arrest and the occurrence of intraoperative bradycardia that were significant risk factors for shunt thrombosis and mortality. Achieving better quality of perioperative care potentially improves outcomes.