Targeted temperature management in adult cardiac arrest: Systematic review and meta-analysis

Abstract

Aim: To perform a systematic review and meta-analysis on targeted temperature management in adult cardiac arrest patients. Methods: PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched on June 17, 2021 for clinical trials. The population included adult patients with cardiac arrest. The review included all aspects of targeted temperature management including timing, temperature, duration, method of induction and maintenance, and rewarming. Two investigators reviewed trials for relevance, extracted data, and assessed risk of bias. Data were pooled using random-effects models. Certainty of evidence was evaluated using GRADE. Results: The systematic search identified 32 trials. Risk of bias was assessed as intermediate for most of the outcomes. For targeted temperature management with a target of 32-34 °C vs. normothermia (which often required active cooling), 9 trials were identified, with six trials included in metaanalyses. Targeted temperature management with a target of 32-34 °C did not result in an improvement in survival (risk ratio: 1.08 [95%CI: 0.89, 1.30]) or favorable neurologic outcome (risk ratio: 1.21 [95%CI: 0.91, 1.61]) at 90 to 180 days after the cardiac arrest (low certainty of evidence). Three trials assessed different hypothermic temperature targets and found no difference in outcomes (low certainty of evidence). Ten trials were identified comparing prehospital cooling vs. no prehospital cooling with no improvement in survival (risk ratio: 1.01 [95%CI: 0.92, 1.11]) or favorable neurologic outcome (risk ratio: 1.00 [95%CI: 0.90, 1.11]) at hospital discharge (moderate certainty of evidence). Conclusions: Among adult patients with cardiac arrest, the use of targeted temperature management at 32-34 °C, when compared to normothermia, did not result in improved outcomes in this meta-analysis. There was no effect of initiating targeted temperature management prior to hospital arrival. These findings warrant an update of international cardiac arrest guidelines.

Hypothermia versus normothermia after out-of-hospital cardiac arrest: A systematic review and meta-analysis of randomized controlled trials

“…Three recent meta-analyses have been published since the publication of the TTM 2 trial [ [27] , [28] , [29] ]. Fernando et al compared the clinical outcomes with the degree of hypothermia.…”

Brain injury after cardiac arrest: pathophysiology, treatment, and prognosis

“…Results showed that TTM at 33 °C had no beneficial effects or signals thereof on mortality, functional outcome, or quality-of-life at 6 months, and it was associated with significantly more arrythmias with haemodynamic instability. Two subsequent meta-analyses have concluded on a lack of effect of TTM, compared to normothermia, on survival or functional outcomes [ 44 , 45 ] and possible harmful effects by moderate (33–34 °C) or deep ( 31–32 °C) hypothermia [ 44 ]. Based on that evidence, the International Liaison Committee on Resuscitation (ILCOR) has issued updated treatment recommendations [ 46 ] suggesting active prevention of fever for ≥ 72 h by targeting a temperature ≤ 37.5 °C, instead of the previously recommended target of 32–36 °C for ≥ 24 h, for those patients who remain comatose after cardiac arrest.…”

Clinical Validation of Cardiac Arrest Hospital Prognosis (CAHP) Score and MIRACLE2 Score to Predict Neurologic Outcomes after Out-of-Hospital Cardiac Arrest

“…Several prehospital factors can influence OHCA outcomes, such as bystander cardiopulmonary resuscitation (CPR), automated external defibrillator (AED) use, the presence of a witness, emergency medical service (EMS) response time, location of OHCA occurrence, and level of intervention by emergency medical technicians (EMTs) [ 4 , 5 , 6 , 7 ]. Additionally, some post-resuscitation care can impact the prognosis of OHCA, such as target temperature management (TTM), coronary angiography, extracorporeal membrane oxygenation (ECMO) intervention for ECMO facilitated resuscitation, and the level of hospital care [ 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. However, patients who need TTM and ECMO-facilitated resuscitation are typically deeply sedated or comatose due to brain injury and therefore, difficult to evaluate post-resuscitation.…”