Abstract
Background: Renaland intestinal damagelead tomultiple organ dysfunction and death after cardiopulmonary resuscitation (CPR), and can be partly mitigated by therapeutic hypothermia. Currently, continuous renal replacement therapy (CRRT) was demonstrated to be an effectiveway to induce hypothermia. In the present study, we aimed to investigate the influence of CRRT cooling on renal and intestinal damage after CPR based on a porcine model.Methods: 32swine were subjected to ventricular fibrillation for 8 min, while defibrillation was performed at 5 min of CPR. All pigs were randomly allocated to receive CRRT (n = 9), surface cooling (SC, n = 9), normothermia (NT, n = 9) or sham control (Control, n = 5)at 5 min post resuscitation. In the CRRT group, the pigs werecooled by the combination of8-hr CRRT and16-hr SC,a rate of 180 ml/min of blood flow was initially set with the infusion line submerged in 4 °C of ice water. In the SC group, pigs were cooled by the 24-hr SC.As to theNT and Controlgroups, thetemperatures were maintained at a normal range. The levels of creatinine (Cr), blood urea nitrogen (BUN), intestinal fatty acid binding protein (IFABP) and diamine oxidase (DAO) in serum were measured at baseline and at 1, 3, 6, 12, 24and30h post resuscitation. Additionally, tissues of kidney and intestine were harvested, from which the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), the contents of malondialdehyde (MDA), activities of superoxide dismutase (SOD) and theapoptosis levels were analyzed.Results:After resuscitation, the blood temperature decreasedsignificantlymore rapidlyin the CRRT group than in the SC group (9.8±1.6vs. 1.5±0.4 ℃/h, P <0.01). The levels of Cr, BUN, IFABP and DAOafter resuscitation were significantly lower in the two hypothermic groupscompared with the NT group. Furthermore, from pathological evidence, cooling induced by CRRTalleviated post-resuscitation renaland intestinal injury compared to SC.Conclusion:Fast hypothermia induced by continuous renal replacement therapy was superior to surface cooling in mitigating renal and intestinal injury post resuscitation.