ObjectiveTo systematically review the efficacy and safety of intravascular cooling versus surface cooling for induced mild hypothermia on the prognosis of patients with cardiac arrest (CA) after resuscitation.MethodsPubMed, EMbase, The Cochrane Library, CNKI and WanFang Data databases were electronically searched to collect cohort studies and randomized controlled trials (RCTs) about the efficacy and safety of intravascular cooling versus surface cooling for CA patients after resuscitation from inception to July 2019. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using Stata 13.0 software.ResultsA total of 9 cohort studies and 3 RCTs involving 2 104 patients were included. The results of meta-analysis showed that: the rate of good neurological function was significantly higher (OR=1.45, 95%CI 1.18 to 1.78, P<0.001) and the induction time was significantly shorter (SMD=−1.35, 95%CI −2.34 to −0.36, P=0.008) in the intravascular cooling group, but there was no statistical difference in mortality between two groups (OR=0.84, 95%CI 0.70 to 1.00, P=0.053). In terms of complications related to mild hypothermia, the rate of excessive hypothermia (OR=0.27, 95%CI 0.18 to 0.41, P<0.001) and arrhythmia (OR=0.60, 95%CI 0.40 to 0.89, P=0.012) was significantly lower in the patients treated with intravascular cooling, but the incidence of coagulopathy was higher (OR=1.61, 95%CI 1.05 to 2.49, P=0.03). There was no statistical difference in the incidence of pneumonia between two groups (OR=1.20, 95%CI 0.94 to 1.53, P=0.147).ConclusionCurrent evidence shows that intravascular cooling has significant neurological protection for patients with CA compared with surface cooling since it can decrease the induction time and the rate of excessive hypothermia and arrhythmia, but it may have a negative effect on the coagulation function. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusion.