Perioperative Outcomes in Stage 1 Palliated Infants Undergoing Noncardiac Procedures: A Comparison by Shunt Type

BACKGROUND: Interstage infants with single-ventricle (SV) physiology following Stage I palliation represent a high-risk population for noncardiac procedures requiring anesthesia. Data comparing perioperative outcomes by shunt type remain limited. AIMS: Describe anesthetic management, perioperative complications, and postoperative outcomes in interstage SV infants undergoing noncardiac interventions and compare outcomes between right ventricle-to-pulmonary artery (Sano) and modified Blalock-Taussig-Thomas shunt (mBTTS) patients. METHODS: We performed a retrospective single-center cohort study of interstage SV infants with Stage I palliation undergoing noncardiac surgery or nonsurgical procedures requiring anesthesia between 2015 and 2023. Outcomes were stratified by shunt type. RESULTS: A total of 208 noncardiac interventions in 120 interstage SV infants were analyzed; 136 (65.4%) encounters in 86 Sano patients and 72 (34.6%) encounters in 34 mBTTS patients. Compared with mBTTS infants, Sano patients underwent interventions at a younger age (57 [IQR 40-83] vs. 105 [59-278] days, p < 0.001) and lower weight (3.6 [3.0-4.1] vs. 4.8 [3.4-7.3] kg, p < 0.001). mBTTS procedures had higher rates of ventricular dysfunction (34.3% vs. 12.7%, p < 0.001), chromosomal abnormalities (63.9% vs. 19.1%, p < 0.001), gastrointestinal comorbidities (87.5% vs. 72.1%, p = 0.014), and hematologic comorbidities (41.7% vs. 22.8%, p = 0.006). Hemodynamic instability requiring vasoactive support was the most common perioperative complication and occurred similarly between groups (31.9% mBTTS vs. 31.6% Sano, p = 0.962). There were no perioperative cardiac arrests. Rates of postoperative escalation of care (2.9%), reintubation (3.0% vs. 2.9%, p = 0.999), readmission (16.2% vs. 16.9%, p = 0.999), and 30-day mortality (2.3% vs. 2.9%, p = 0.999) were low and comparable between groups. CONCLUSIONS: Despite the high-risk physiology of interstage SV patients, perioperative outcomes were comparable between Sano and mBTTS cohorts. However, these findings should be interpreted cautiously and should not imply low procedural risk. Favorable outcomes likely reflect careful patient selection, multidisciplinary perioperative care, and specialized institutional expertise.