Surgery in cyanosis: Anesthetic lessons from a rare encounter in adult with double-outlet left ventricle

Sir, Adults living with uncorrected double-outlet left ventricle (DOLV) are extremely rare. Double-outlet ventricles where both great arteries arise predominantly from one ventricular chamber despite normal atrioventricular connections constitute only about 1% of all congenital heart diseases (CHDs).[1,2] Most studies estimate that DOLV represents <5% of all double-outlet ventricles, translating to an approximate prevalence of <0.05% of all CHD. In practical terms, this means that fewer than 1 in 200,000 live births have DOLV. Because the condition typically produces significant cyanosis or heart failure in infancy, most patients undergo early corrective or palliative surgery.[3] Consequently, it is exceptionally unusual for an individual with uncorrected DOLV to survive into adulthood, the presentation of an adult with unrepaired physiology undergoing noncardiac surgery poses significant and largely unexplored anesthetic challenges. We wish to share our experience with a 38-year-old male with uncorrected DOLV who successfully underwent scleral buckling under monitored anesthesia care (MAC). This report highlights specific physiological considerations, clarifies safe regional anesthetic practice, and details backup strategies that address the gaps noted in the existing literature. The patient had a childhood diagnosis of DOLV with levocardia, severe pulmonary stenosis (peak gradient 78 mmHg), and a large right-to-left shunt. He had never undergone corrective cardiac surgery. His medical history was notable for a prior ischemic stroke with residual right-sided weakness and chronic phenytoin therapy. On presentation, his vital signs were: heart rate –94/min, blood pressure –118/62 mmHg, respiratory rate –20/min, and SpO2 –78%–80% on room air. Physical examination revealed central cyanosis, clubbing, and a grade 3/6 ejection systolic murmur. Laboratory results showed hemoglobin of 18.6 g/dL, hematocrit 61%, platelets 140 × 109/L, and INR 1.1. Echocardiography documented DOLV with malaligned ventricular septal defect, severe pulmonary stenosis, and preserved ventricular systolic function. Given the chronic hypoxemia and high pulmonary outflow resistance, general anesthesia risked increased right-to-left shunting, systemic desaturation, and hemodynamic collapse.[4,5] A multidisciplinary discussion favored regional ophthalmic anesthesia with MAC, while maintaining spontaneous ventilation and avoiding increases in pulmonary vascular resistance (PVR). A retrobulbar block was carefully performed using 3 mL of 2% lignocaine with judicious titration of 0.5 mg midazolam and 15 μg fentanyl, maintaining SpO2 between 80% and 84% on supplemental oxygen at 2 L/min. Hemodynamic remained stable (mean arterial pressure 68–74 mmHg) with no arrhythmias or complications during the 55-min procedure. A comprehensive backup plan was consistent with contemporary recommendations for adults with complex CHD.[5,6,7] Low-dose etomidate was selected for induction to preserve systemic vascular resistance (SVR); Maintenance anesthesia comprised an air-oxygen mixture with low-dose sevoflurane and opioids to minimize systemic vasodilation while maintaining hemodynamic stability. Invasive arterial monitoring would guide management, with strict avoidance of hypercarbia, hypoxia, and elevated airway pressures to prevent PVR escalation. Norepinephrine was prepared as the primary vasopressor for rapid hemodynamic support, supplemented by phenylephrine if needed, while all intravenous lines were equipped with bubble filters to mitigate the risk of paradoxical air embolism in this patient.[5,6] Postoperative intensive care unit observation was planned to monitor for delayed desaturation, arrhythmias, and hemodynamic instability in this complex, uncorrected cyanotic congenital heart lesion. The patient maintained SpO2 between 78% and 82% in the recovery area, with no neurological events or arrhythmias and was discharged the following day after an uneventful postoperative course. The educational significance of this case lies not merely in its rarity, but in the opportunity to outline safe dosing strategies, describe real-time physiological responses, and present a structured perioperative risk-mitigation framework applicable to similar cyanotic CHD pathophysiology. Patients living with chronic cyanosis develop profound adaptive changes including erythrocytosis, hyperviscosity, impaired microcirculatory flow, pro-thrombotic tendency, and increased susceptibility to neurological injury.[8,9] In this setting, anesthetic goals must emphasize the preservation of SVR, strict avoidance of PVR-elevating triggers (hypoxia, hypercarbia, acidosis, and pain), and maintenance of optimal oxygen delivery. Even minimal fluctuations in hemodynamics may precipitate shunt reversal, hypoxemia, or paradoxical embolization. Although MAC and regional ophthalmic blocks are frequently used for ophthalmic surgery, their application in uncorrected DOLV poses specific hazards. Excessive sedation may depress ventilation and increase PVR; high-volume local anesthetic injection risks systemic toxicity or hemodynamic perturbation; and hypotension from local anaesthetic spread or sedative agents can be poorly tolerated. Our approach carefully titrated sedation, low-volume regional block, invasive monitoring, predefined escalation pathways, and continuous shunt physiology assessment demonstrated that regional techniques can be feasible and safe when grounded in a detailed physiological understanding.[6,7] This case highlights a critical gap in contemporary anesthesia guidelines: The absence of structured recommendations for regional anesthesia in rare adult CHD phenotypes such as DOLV.[7] We believe the present report contributes to this space by offering practical insights and a replicable checklist-based strategy. As survival into adulthood increases among patients with complex CHD, anesthesiologists in noncardiac specialties will increasingly encounter similar situations where conventional techniques require nuanced adaptation. We hope this case stimulates discussion on tailored perioperative planning for adults with uncorrected congenital lesions and underscores the need for updated consensus guidance incorporating physiological principles relevant to this growing patient cohort. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.