D. K. Robie1, D. K. Robie1 1Mayo Clinic – Florida,Surgery,Jacksonville, FL, USA
Introduction:
The separation of conjoined twins requires thorough preoperative assessment, detailed operative planning, optimization of each twin’s medical status and multidisciplinary team preparation. Since each set of conjoined twins is unique and the condition is extremely rare, both surgeon and institutional experience will be limited. Our recent experience in separating omphalopagus conjoined twins highlighted the importance of these preparatory steps. The purpose of this review is to identify the key prognostic indicators that impact on survival.
Methods:
PUBMED was searched for publications on conjoined twin separations and operations performed between 1988 and 2015 were included in this review. Data gathered included type of conjoining; age at operation; whether emergent or elective separation; if emergent the primary indication for surgery; complexity of organ sharing; mortality and cause of death; survival. Significance of categorical variables on survival was determined using univariate analysis and the mean and median time to the separation operation determined.
Results:
There were 109 separations reviewed. Type of conjoining and % of total as follows: Omphalopagus (OP) 51 (47%), Thoracopagus (TP) 25 (23 %), Ischiopagus (IP) 22 (20%), Parapagus (PP) 5 (5%), Pygopagus (PGP) 4 (4%) and Craniopagus (CP) 2 (2%). Elective separation, survival and age at separation (range; median and mean in months (ms)): 29 OP sets (1 d to 12 ms, 1.25 ms, 3.6 ms) with 95% survival, ; 13 TP sets (1 m to 16ms, 4.5 ms, 6.3 ms) with 81% survival, 20 IP sets (1d to 26 ms, 10.5 ms, 12 ms) with 92.5% survival. Emergency separation and survival: 22 OP sets with 54% survival, 13 TP sets with 29% survival, 2 IP sets with 25% survival. Causes of death in total group(n): planned sacrifice 1, dependent parasite 2, severe congenital heart disease 13, pulmonary 7, sepsis 9, other 9 and unknown 7. Seven infants died intraoperatively and 7 died preoperatively. Indication for emergency separation and % survival; preop twin demise 7 sets (43%), clinical deterioration of one or both twins 16 (24%). 26 infants had severe congenital heart disease (5 with cardiac fusion) with 19 % survival. Predictors of adverse outcome; TP type, emergency separation, preoperative twin demise and presence of severe congenital heart disease.
Conclusion:
Survival following separation of conjoined twins is dependent on the type of conjoining, emergency versus elective separation, the presence of severe cardiac anomalies and the immediate condition of the infants prior to surgery. When time allows, efforts should be focused on maximizing the clinical condition of the infants prior to separation. It is important that the treatment team and the family are aware of the prognosis based on the unique aspects of the individual set of twins.