The H 2 S Donor Sodium Thiosulfate (Na 2 S 2 O 3 ) Does Not Improve Inflammation and Organ Damage After Hemorrhagic Shock in Cardiovascular Healthy Swine

We previously demonstrated marked lung-protective properties of the H S donor sodium thiosulfate (Na S O , STS) in a blinded, randomized, controlled, long-term, resuscitated porcine model of swine with coronary artery disease, i.e., with decreased expression of the H S-producing enzyme cystathionine-γ-lyase (CSE). We confirmed these beneficial effects of STS by attenuation of lung, liver and kidney injury in mice with genetic CSE deletion (CSE-ko) undergoing trauma-and-hemorrhage and subsequent intensive care-based resuscitation. However, we had previously also shown that any possible efficacy of a therapeutic intervention in shock states depends both on the severity of shock as well as on the presence or absence of chronic underlying co-morbidity. Therefore, this prospective, randomized, controlled, blinded experimental study investigated the effects of the STS in cardiovascular healthy swine. After anesthesia and surgical instrumentation, 17 adult Bretoncelles-Meishan-Willebrand pigs were subjected to 3 hours of hemorrhage by removal of 30% of the blood volume and titration of the mean arterial pressure (MAP) ≈ 40 ± 5 mmHg. Afterwards, the animals received standardized resuscitation including re-transfusion of shed blood, fluids, and, if needed, continuous i.v. noradrenaline to maintain MAP at pre-shock values. Animals were randomly allocated to either receive Na S O or vehicle control starting 2 hours after initiation of shock until 24 hours of resuscitation. The administration of Na S O did not alter survival during the observation period of 68 hours after the initiation of shock. No differences in cardio-circulatory functions were noted despite a significantly higher cardiac output, which coincided with significantly more pronounced lactic acidosis at 24 hours of resuscitation in the Na S O group. Parameters of liver, lung, and kidney function and injury were similar in both groups. However, urine output was significantly higher in the Na S O group at 24 hours of treatment. Taken together, this study reports no beneficial effect of Na S O in a clinically relevant model of hemorrhagic shock-and-resuscitation in animals without underlying chronic cardiovascular co-morbidity.