B. Willobee1, M. Mulder1, E. A. Perez1, A. R. Hogan1, A. Brady1, H. Neville1, J. E. Sola1, C. M. Thorson1 1University of Miami,Pediatric Surgery,Miami, FL, USA
Introduction: Conjoined twins are rare developmental anomalies. There is a paucity of literature other than case reports and small case series. The aim of this study was to examine national outcomes and identify predictors of mortality in newborn conjoined twins.
Methods: Patients born with a diagnosis of conjoined twins were identified in the Kids' Inpatient Database (1997-2012). Patient demographics, associated anomalies, operative procedures and outcomes were identified and analyzed using standard statistical methods.
Results: A total of 248 patients were identified for a nationally weighted incidence of 1 per 100,000 live births. The majority were female (n=197, 80%). The most common associated anomalies were cardiac (n=90, 36%), gastrointestinal (n=43, 17%), abdominal wall defects (n=32, 13%), and genitourinary (n=28, 12%). Prematurity was seen in 59% (n=147) and 45% (n=112) were classified as low (27%), very low (8%) or extremely low (11%) birth weight. Fifty-eight patients (24%) underwent operative procedures during the primary hospitalization, including 27 (11%) who had neonatal separation surgery.
The overall mortality was 62% with most deaths occurring just after birth (104/153, 68%) or within the first 48 hours of life (134/152, 88%). Mortality was significantly higher in infants who were female vs. male (67% vs. 36%, p=<0.001), premature vs. full term (72% vs. 46%, p<0.001), low birth weight (73% vs. 58%, p=0.031) and extremely low birth weight (96% vs. 58%, p<0.001). Congenital diaphragmatic hernias were seen in 15 patients (6%) and were uniformly fatal (100% vs. 59%, p=0.002). Mortality was highest in hospitals not designated as children’s hospital (71%) vs. hospitals with a children’s unit or free-standing children’s hospital (42%), p=0.01. Greater than 50% of all deaths were in hospitals not designated as a children’s hospitals. Multiple logistic regression revealed prematurity (OR 2.3 [1.06-4.84], p=0.034) and non-children’s hospital designation (OR 2.3 [1.09-5.02], p=0.029] to be independent predictors of mortality.
Conclusion: Conjoined twins are rare defects and are often associated with multiple anomalies. They experience an extremely high perinatal mortality, especially females, those who are premature, low birth weight, or with diaphragmatic hernias. This data supports caring for these complex patients at hospitals designated for children.