Hachimi‐Idrissi 2001.

Study characteristics
Methods	Study type: RCT Aim of the study: efficacy Participating sites: 1 university hospital in Brussels, Belgium Language: English Start date, end date: 6‐month period (dates not provided)
Participants	Number randomised: 33 Inclusion criteria: people with asystole or PEA of presumed cardiac origin who achieved ROSC, aged > 18 years, with tympanic temperature > 30 °C at admission to the emergency department, GCS < 7, haemodynamically stable at start of study Exclusion criteria: pregnant, known coagulopathy, history of central nervous system depressant drug medication prior to cardiac arrest Mean age: 72 years Women: 39% Cardiac arrest location: out‐of‐hospital Cause of cardiac arrest: cardiac Primary cardiac rhythm: asystole or PEA Witnessed cardiac arrest: 53% Bystander CPR: 7% Timing cardiac arrest (out‐of‐hospital cardiac arrest) (minutes): collapse to EMS call: 2 (range 1–3) (intervention); 2, (range 1–17) (control) collapse to ICU arrival: 10 (range 1–19) (intervention); 12 (range 8–28) (control) collapse to ROSC: 34 (range 17–82) (intervention); 33 (range 25–50) (control) Temperature on admission/at start of cooling: 35.5 °C (intervention); 35.5 °C (control) Subgroups reported: none
Interventions	Therapeutic hypothermia vs standard postresuscitation care protocol Means of cooling: helmet device placed around head and neck and containing a solution of aqueous glycerol Cooling rate: starting point until target temperature not clearly stated Target temperature: 34 °C Duration of cooling: start of cooling to start of rewarming: 4 hours Was intervention started within 2 hours after ROSC? yes Was target temperature reached within 4 hours of ROSC? yes Timing of intervention (minutes): collapse to start of study/start of TTM: 102 (intervention); 99 (control) start of intervention to target temperature: 180 (bladder temperature), 60 (central temperature) ROSC to target temperature: 128 (according to central temperature) and 248 (according to bladder temperature) Rewarming: passive over 8 hours
Outcomes	Haemodynamic data, arterial pH, electrolytes, haematological data Complications such as pneumonia, sepsis, cardiac arrhythmia and coagulopathy Survival to hospital discharge and OPCs Best ever reached CPC during hospital stay and CPC discharge provided
Control group treatment	In the normothermia group, the initial hypothermic participants were rewarmed passively. A temperature above 38 °C was actively treated with intravenous paracetamol. The postresuscitation care protocol was the same as for the hypothermia group.
Funding source
Notes	Randomisation: random number tables Authors provided completed data on 33 participants; the publication reported on only 30 participants as follow‐up was not completed at the time of submission.