Arterio-venous CO₂ removal (AVCO₂R) perioperative management: Rapid recovery and enhanced survival

Percutaneous arteriovenous CO₂ removal (AVCO₂R) uses a simple arteriovenous (A-V) shunt for near-total CO₂ removal that allows significant reductions in minute ventilation. We critically reviewed our algorithm-directed perioperative anesthesia management in our LD₄₀ ovine smoke-burn injury model of acute respiratory distress syndrome (ARDS) treated with AVCO₂R. General anesthesia is required for: (1) Vascular access followed by ARDS model development by smoke insufflation (36 breaths) plus 40% TBSA III° burn with mechanical ventilation. Induction: 12.5 mg/kg im ketamine and 4% halothane by mask, then intubation. Maintenance: 1.0-2.5% halothane in 100% O₂; (2) When PaO₂/FiO₂ < 200 (48-52 h), sheep randomized to the AVCO₂R (n = 8) or SHAM (n = 8) procedure. Induction: 66% N₂O and 5% isoflurane in balance O₂. Maintenance: 1.5-2.5% isoflurane in 100% O₂ for AVCO₂R, cannulation (10F carotid artery, 14F jugular vein); (3) Postop, both groups had algorithm-directed ventilator management, identical heparin (ACT > 300 s), fluid, and analgesia management. All sheep met criteria for ARDS, survived anesthesia, and were standing by 0.5-5 h. There were no complications attributable to anesthesia. The absence of anesthesia-related complications allows model development for outcomes studies for ARDS in general and AVCO₂R specifically.