Table 1.
Demographic characteristics of the study population stratified according to neurological outcome and temperature treatment
| Characteristica | Good outcome (N = 31) |
Poor outcome (N = 47) |
33 °C group (N = 41) | 36 °C group (N = 37) |
|---|---|---|---|---|
| Demographic characteristics | ||||
| Age in years | 62 ± 11 | 69 ± 12 | 64 ± 13 | 68 ± 11 |
| Male sex | 27 (87) | 35 (75) | 36 (88) | 26 (70) |
| Medical history | ||||
| Chronic heart failure | 1/28 (4) | 4/44 (9) | 1/39 (3) | 4/33 (12) |
| Previous acute myocardial infarction | 5/28 (18) | 9/44 (21) | 8/39 (21) | 6/33 (18) |
| Ischaemic heart disease | 5/28 (18) | 12/44 (27) | 9/39 (23) | 8/33 (24) |
| Previous cardiac arrhythmia | 5/28 (18) | 12/44 (27) | 8/39 (21) | 9/33 (27) |
| Arterial hypertension | 13/28 (46) | 21/44 (48) | 19/39 (49) | 15/33 (46) |
| Previous TIA or stroke | 1/28 (4) | 9/44 (21) | 4/39 (10) | 6/33 (18) |
| Diabetes mellitus | 1/28 (4) | 9/44 (21) | 3/39 (8) | 7/33 (21) |
| Asthma or COPD | 4/28 (14) | 7/44 (16) | 2/39 (5) | 9/33 (27) |
| Previous percutaneous coronary intervention | 2/28 (7) | 5/44 (11) | 4/39 (10) | 3/33 (9) |
| Previous coronary-artery bypass grafting | 0/28 (0) | 5/44 (11) | 5/39 (13) | 0/33 (0) |
| Characteristics of the cardiac arrest | ||||
| Bystander witnessed cardiac arrest | 28 (90) | 45 (96) | 37 (90) | 36 (97) |
| Shockable rhythm | 27 (87) | 23 (49) | 28 (68) | 22 (59) |
| Minutes from cardiac arrest to ROSC | 23 (15–33) | 35 (23–50) | 30 (20–43) | 30 (19–48) |
| Clinical characteristics on admission | ||||
| First measured body temperature in °Cd | 35.9 ± 0.8 | 35.9 ± 0.9 | 35.7 ± 0.9 | 36.0 ± 0.8 |
| Glasgow Coma Scale scoreb,d | 5 (4–6) | 3 (3–3) | 3 (3–5) | 3 (3–5) |
| Corneal reflex bilaterally present | 16/26 (62) | 8/44 (18) | 14/38 (37) | 10/32 (31) |
| Pupillary reflex bilaterally present | 27/30 (90) | 19/47 (40) | 24/40 (60) | 22/37 (60) |
| Serum pHd | 7.3 ± 0.1 | 7.1 ± 0.2 | 7.2 ± 0.1 | 7.1 ± 0.2 |
| Serum lactate in mmol/literd | 6.2 ± 3.7 | 9.2 ± 4.2 | 7.5 ± 4.1 | 8.7 ± 4.5 |
| Circulatory shockc | 2/28 (7) | 7/44 (16) | 4/39 (10) | 5/33 (15) |
| ST-segment elevation in acute myocardial infarction | 11/28 (39) | 12/44 (27) | 12/39 (31) | 11/33 (33) |
| Allocation to 33 °C | 20 (65) | 21 (45) | 41 (100) | 0 (0) |
| Poor outcome (CPC 3–5) at 6 months | 0 (0) | 47 (100) | 21 (51) | 26 (70) |
aResults are reported as numbers [/total number] (percentages), median (interquartile range), or mean (± standard deviation) as appropriate. COPD chronic obstructive pulmonary disease; TIA transient ischaemic attack; ROSC return of spontaneous circulation
bScores on the Glasgow Coma Scale range from 3 to 15, with lower scores indicating reduced level of consciousness
cCirculatory shock was defined as a systolic blood pressure of less than 90 mm Hg for more than 30 min or end-organ hypoperfusion (cool extremities, urine output < 30 ml per hour, and a heart rate of < 60 beats per minute)
dMissing values. ‘First measured body temperature’ was missing data for 2 patients and ‘Glasgow Coma Scale score’ was missing data for 8 patients; ‘Serum pH’ and ‘Serum lactate’ were missing data for 6 patients