Risk factors and outcomes of early postoperative complications following congenital heart surgery: a retrospective study at a tertiary care hospital in Nairobi, Kenya

Abstract Introduction Congenital Heart Disease (CHD) remains a major health challenge globally, with surgical interventions being the primary treatment modality for many defects. While advancements in cardiac surgery have improved survival rates, early postoperative complications continue to pose risks, particularly in settings with limited resources like Kenya. The study aimed to assess the rate of any early postoperative complications and identify factors associated with it in children after cardiac surgery at a tertiary care hospital in Nairobi, Kenya from 2019 to 2024. Methods This was an single-center retrospective study including children (< 18 years) who underwent cardiac surgery due to congenital heart disease at a tertiary care hospital in Nairobi, Kenya, over a 5-year period. Categorical variables were described as frequencies and percentages, while continuous variables were described as medians with interquartile ranges (IQR). Categorical variables were compared using chi-square or Fisher exact test and continuous variables compared using Mann-Whitney U test. Variables with p-value < 0.1 in the univariable analysis were included in the multivariable logistic regression, with p-value < 0.05 set as the level of significance. All analyses were performed using Rstudio version 4.5.1. Results A total of 97 children were included in the study. The median age in months was 25.0 (IQR: 8.5–67.5) and 50 (51.5%) were male. Patent ductus arteriosus, ventricular septal defect, and atrial septal defect were the predominant preoperative diagnoses. At least one early postoperative complication occurred in 52.6% (95%CI: 42.6% to 62.5%) of the children. Preoperative oxygen saturation (AOR: 0.92; 95%CI: 0.85–0.98, p = 0.021) and closed heart surgery (AOR:0.32; 95%CI:0.11–0.86, p = 0.027) were significantly associated with early postoperative complications. Conclusion The study findings highlight gaps and opportunities in perioperative care of children undergoing congenital heart surgery at a tertiary care center in Kenya. Preoperative oxygen saturation and closed heart surgery were independently associated with reduced odds of early postoperative complications. These findings suggest that optimizing preoperative physiological status and further investigating the factors driving the association between surgical approach and outcomes may inform strategies to improve perioperative care in this setting.