- Cardiopulmonary bypass (CBP) is associated with a systemic inflammatory response that can result in profound hypotension refractory to vasopressors, a condition known as vasoplegic syndrome, or vasoplegia.
- Hydroxocobalamin (HCO) has been suggested as a treatment for vasoplegia given its ability to scavenge, bind, and prevent the formation of nitric oxide (NO) and hydrogen sulfide, both of which may contribute to vasodilation and hypotension.
- This randomized placebo-controlled prospective trial investigated the prevention of vasoplegia in high-risk patients undergoing cardiac surgery via administration of prophylactic HCO compared to placebo at the time of separation from CPB.
- Thirty patients were randomized to receive HCO 5g IV (reconstituted in 200ml saline), and 30 patients were randomized to receive IV saline, upon separation from CPB in cardiac surgery.
- Results: Mean arterial pressure (MAP) was significantly higher at both 30 and 60 minutes following separation from CPB in the HCO group compared to the placebo group. At 30 minutes, the mean MAP was 77.6mmHg in the HCO group versus 66.6mmHg in the placebo. At 60 minutes, the mean MAP was 81.9mmHg in the HCO group versus 65.4mmHg in the placebo group.
- The HCO group had a statistically significant lower total dose requirements of norepinephrine, lower rates of vasoplegic shock syndrome, lower rates of vasoplegia refractory to norepinephrine, and lower average serum lactate levels.
- HCO administration did not result in significant differences in ICU or hospital length of stay, 1 week mortality, multiorgan failure.
- The authors concluded that prophylactic HCO administration can reduce the rates of hypotension, including vasoplegic shock syndrome, in high-risk cardiac surgery patients undergoing CPB.
- Larger studies are required to investigate the role for prophylactic HCO in improving long-term outcomes, including mortality.
Summary of "Use of Hydroxycobolamin in the Prevention of Vasoplegic Syndrome in Adult Patients Undergoing Cardiopulmonary Bypass: A Controlled Prospective Trial"
Summary published September 15, 2025
