Background
Methods
Study design, setting, and patient selection
Data collection
Primary exposure
Outcome measures
Statistical analysis
Results
Baseline patient characteristics
Variables | Inclusion n = 435 | No TTM n = 2013a | p valuec | TTM withdrawal n = 161b | p valuec | Unknown lactate concentration n = 112 | p valuec |
---|---|---|---|---|---|---|---|
Age, years | 63 [50, 73] | 75 [6, 83] | < 0.001 | 65 [53, 75] | 0.126 | 63 [51, 72] | 0.881 |
Age > 65 years | 182 (42) | 1405 (70) | < 0.001 | 78 (48) | 0.163 | 51 (46) | 0.521 |
Male sex | 338 (78) | 1190 (59) | < 0.001 | 115 (71) | 0.130 | 85 (76) | 0.705 |
Witness | 348 (80) | 1312 (65) | < 0.001 | 122 (76) | 0.261 | 83 (74) | 0.195 |
Dispatcher instruction | 198 (46) | 852 (42) | 0.24 | 75 (47) | 0.853 | 45 (40) | 0.338 |
Bystander-performed CPR | 228 (52) | 839 (42) | < 0.001 | 88 (55) | 0.645 | 50 (45) | 0.168 |
Cardiac etiology | 332 (76) | 786 (39) | < 0.001 | 128 (80) | 0.443 | 85 (76) | 0.902 |
Initial shockable rhythm | 235 (54.0) | 218 (11) | < 0.001 | 74 (46) | 0.096 | 54 (48) | 0.290 |
Prehospital epinephrine administration | 99 (23) | 613 (31) | 0.001 | 57 (35) | 0.001 | 29 (26) | 0.532 |
Prehospital advanced airway management | 145 (33) | 871 (43) | < 0.001 | 61 (38) | 0.332 | 43 (38) | 0.318 |
Prehospital AED | 313 (72) | 777 (39) | < 0.001 | 110 (68) | 0.416 | 73 (65) | 0.165 |
Response time, min | 8 [6, 9] | 8 [7, 10] | < 0.001 | 8[7, 10] | < 0.001 | 8 [6, 10] | 0.197 |
Time from call to hospital arrival, min | 30 [24, 36] | 32 [27, 40] | < 0.001 | 32 [27, 40] | 0.014 | 30 [24, 36] | 0.942 |
Prehospital ROSC | 252 (58) | 563 (28) | < 0.001 | 36 (22) | < 0.001 | 28 (25) | < 0.001 |
Glasgow Coma Scale score | 3 [3, 3] | 3 [3, 3.] | < 0.001 | 3 [3, 3] | < 0.001 | 3 [3, 3] | 0.003 |
Coronary angiography | 257 (59) | 235 (12) | < 0.001 | 100 (62) | 0.512 | 75 (67) | 0.131 |
ECMO and/or IABP | 123 (28) | 157 (8) | < 0.001 | 76 (47) | < 0.001 | 54 (48) | < 0.001 |
Targeted temperature management | NA | 0.198 | 0.005 | ||||
32–34 °C | 319 (73) | 0 (0) | 124 (79) | 92 (86) | |||
35–36 °C | 116 (27) | 0 (0) | 33 (21) | 15 (14) | |||
30-day favorable neurological outcome | 182 (42) | 183 (9) | < 0.001 | 20 (12) | < 0.001 | 32 (29) | 0.012 |
30-day survival | 325 (75) | 354 (18) | < 0.001 | 36 (22) | < 0.001 | 67 (60) | 0.003 |
Association of serum lactate concentrations after ROSC and favorable neurological outcomes
Variables | Hyperlactatemia classification | p value | ||
---|---|---|---|---|
Mild n = 139 | Moderate n = 182 | Severe n = 114 | ||
Age, years | 64 [52, 73] | 64 [50, 75] | 60 [48, 68] | 0.087 |
Age > 65 years | 63 (45) | 81 (45) | 38 (33) | 0.098 |
Male sex | 105 (76) | 143 (79) | 90 (79) | 0.757 |
Witness | 118 (85) | 149 (82) | 81 (71) | 0.017 |
Dispatcher instruction | 66 (47) | 89 (49) | 43 (38) | 0.149 |
Bystander-performed CPR | 77 (55) | 100 (55) | 51 (45) | 0.161 |
Cardiac etiology | 115 (83) | 135 (74) | 82 (72) | 0.089 |
Initial shockable rhythm | 88 (63) | 100 (55) | 47 (41) | 0.002 |
Prehospital epinephrine administration | 21 (15) | 41 (23) | 37 (32) | 0.005 |
Prehospital advanced airway management | 33 (24) | 61 (34) | 51 (45) | 0.002 |
Prehospital AED | 114 (82) | 132 (73) | 67 (59) | < 0.001 |
Response time, min | 8 [6, 9] | 8 [6, 9] | 8 [7, 9] | 0.376 |
Time from call to hospital arrival, min | 32 [25, 39] | 30 [24, 35] | 29 [24, 37] | 0.200 |
Prehospital ROSC | 102 (73) | 112 (62) | 38 (33) | < 0.001 |
Glasgow Coma Scale score | 3 [3, 4] | 3 [3, 3] | 3 [3, 3] | < 0.001 |
Coronary angiography | 85 (61) | 106 (58) | 66 (58) | 0.833 |
ECMO and/or IABP | 45 (32) | 37 (20) | 41 (36) | 0.006 |
Door-to-first ABG measurement after ROSC, min | 11 [5, 30] | 9 [5, 18] | 15 [7, 30] | 0.007 |
pH | 7.28 [7.22, 7.33] | 7.12 [7.02, 7.28] | 6.92 [6.75, 7.03] | < 0.001 |
PaCO2, mm Hg | 43 [37, 51] | 52 [35, 75] | 70 [43, 97] | < 0.001 |
PaCO2 30–50 mm Hg | 90 (65) | 63 (35) | 27 (24) | < 0.001 |
PaO2, mm Hg | 176 [91, 337] | 187 [92, 356] | 150 [79, 346] | 0.760 |
HCO3, mmol/l | 19.9 [17.1, 21.7] | 16.4 [13.9, 18.6] | 12.9 [10.3, 16.8] | < 0.001 |
Base excess, mmol/l | − 6.2 [− 9.1, − 4.0] | − 12 [− 14.7, − 9.5] | − 19.4 [− 24.1, − 15.4] | < 0.001 |
Lactate value, mmol/l | 5.2 [3.7, 6.1] | 9.1 [7.9, 10.2] | 14.9 [13.2, 18.0] | < 0.001 |
Door-to-TTM initiation, min | 106 [30, 188] | 115 [36, 190] | 136 [46, 225] | 0.324 |
Targeted temperature management | 0.331 | |||
32–34 °C | 108 (78) | 128 (70) | 83 (73) | |
35–36 °C | 31 (22) | 54 (30) | 31 (27) | |
30-day favorable neurological outcome | 84 (60) | 76 (42) | 22 (19) | < 0.001 |
30-day survival | 117 (84) | 144 (79) | 64 (56) | < 0.001 |
Baseline characteristics of patients stratified by hyperlactatemia and treated with 32–34 °C or 35–36 °C
Variables | Mild hyperlactatemia | p value | Moderate hyperlactatemia | p value | Severe hyperlactatemia | p value | |||
---|---|---|---|---|---|---|---|---|---|
32–34 °C n = 108 | 35–36 °C n = 31 | 32–34 °C n = 128 | 35–36 °C n = 54 | 32–34 °C n = 83 | 35–36 °C n = 31 | ||||
Age, years | 64 [52, 72] | 66 [54, 79] | 0.105 | 62 [50, 74] | 71 [51, 80] | 0.036 | 58 [47, 67] | 64 [55, 71] | 0.112 |
Age > 65 years | 47 (43.5) | 16 (51.6) | 0.540 | 50 (39) | 31 (57) | 0.033 | 24 (28.9) | 14 (45.2) | 0.121 |
Male sex | 80 (74) | 25 (81) | 0.636 | 101 (79) | 42 (78) | 0.846 | 67 (81) | 23 (74) | 0.449 |
Witness | 92 (85) | 26 (84) | 0.784 | 106 (83) | 43 (80) | 0.675 | 61 (74) | 20 (65) | 0.361 |
Dispatcher instruction | 48 (44) | 18 (58) | 0.222 | 63 (49) | 26 (48) | 1.000 | 31 (37) | 12 (39) | 1.000 |
Bystander-performed CPR | 58 (54) | 19 (61) | 0.540 | 73 (57) | 27 (50) | 0.417 | 39 (47) | 12 (39) | 0.527 |
Cardiac etiology | 90 (83) | 25 (81) | 0.788 | 98 (77) | 37 (69) | 0.271 | 61 (74) | 21 (68) | 0.640 |
Initial shockable rhythm | 74 (69) | 14 (45) | 0.021 | 75 (59) | 25 (46) | 0.144 | 36 (43) | 11 (36) | 0.524 |
Prehospital epinephrine administration | 18 (17) | 3 (10) | 0.409 | 31 (24) | 10 (19) | 0.444 | 27 (33) | 10 (32) | 1.000 |
Prehospital advanced airway management | 24 (22) | 9 (29) | 0.475 | 41 (32) | 20 (37) | 0.606 | 37 (45) | 14 (45) | 1.000 |
Prehospital AED | 90 (83) | 24 (77) | 0.437 | 93 (73) | 39 (72) | 1.000 | 50 (60) | 17 (55) | 0.671 |
Response time, min | 8 [6, 9] | 8 [6, 10] | 0.749 | 7 [6, 9] | 8 [6, 9] | 0.381 | 8 [6, 9] | 8 [7, 11] | 0.329 |
Time from call to hospital arrival, min | 32 [25, 40] | 31 [23, 33] | 0.283 | 30 [24, 34] | 31 [24, 36] | 0.542 | 29 [25, 37] | 28 [24, 39] | 0.769 |
Prehospital ROSC | 77 (71) | 25 (81) | 0.362 | 78 (61) | 34 (63) | 0.868 | 31 (37) | 7 (23) | 0.181 |
Glasgow Coma Scale score | 3 [3, 3] | 3 [3, 6] | 0.097 | 3 [3, 3] | 3 [3, 3] | 0.602 | 3 [3, 3] | 3 [3, 3] | 0.856 |
Coronary angiography | 66 (61) | 19 (61) | 1.000 | 78 (61) | 28 (52) | 0.324 | 52 (63) | 14 (45) | 0.135 |
ECMO and/or IABP | 37 (34.3) | 8 (25.8) | 0.514 | 50 (39) | 13 (24) | 0.061 | 32 (39) | 9 (29) | 0.388 |
Door-to-first ABG measurement after ROSC, min | 11 [5, 32] | 9 [5, 22] | 0.300 | 10 [5, 17] | 9 [6, 18] | 0.784 | 13 [6, 30] | 19 [11, 35] | 0.056 |
pH | 7.28 [7.22, 7.32] | 7.31 [7.20, 7.37] | 0.107 | 7.14 [7.02, 7.28] | 7.08 [7.01, 7.25] | 0.356 | 6.92 [6.81, 7.03] | 6.91 [6.74, 7.15] | 0.817 |
PaCO2, mm Hg | 43 [38, 51] | 40 [33, 51] | 0.318 | 47 [34, 75] | 60 [36, 75] | 0.200 | 69 [44, 90] | 72 [31, 108] | 0.873 |
PaCO2 30–50 mm Hg | 71 (65.7) | 19 (61.3) | 0.674 | 50 (39) | 13 (24) | 0.061 | 23 (28) | 4 (13) | 0.137 |
PaO2, mm Hg | 170 [91, 350] | 176 [93, 325] | 0.975 | 179 [86, 354] | 195 [113, 350] | 0.449 | 148 [76, 345] | 240 [86, 363] | 0.437 |
HCO3, mmol/l | 20.0 [16.8, 21.5] | 19.9 [18.0, 22.8] | 0.608 | 16.3 [13.9, 18.5] | 16.6 [13.6, 19.5] | 0.471 | 13.0 [10.4, 17.1] | 12.7 [10.3, 15.1] | 0.530 |
Base excess, mmol/l | − 6.4 [− 9.3, − 4.0] | − 5.7 [− 7.3, − 4.1] | 0.369 | − 11.9 [− 14.9, − 9.4] | − 12.5 [− 14.0, − 9.9] | 0.905 | − 19.6 [− 23.7, − 16.2] | − 19.4 [− 24.5, − 12.6] | 0.703 |
Lactate value, mmol/l | 5.1 [3.6, 6, 1] | 5.4 [3.9, 6.5] | 0.185 | 9.1 [7.9, 10.1] | 9.3 [8.1, 10.6] | 0.775 | 14.7 [13.1, 17.3] | 16.2 [14.0, 19.4] | 0.113 |
Door-to-TTM initiation, min | 82 [20, 174] | 167 [109, 213] | 0.003 | 78 [21, 170] | 164 [103., 218] | < 0.001 | 105 [35, 202] | 198 [109, 261] | 0.002 |
30-day favorable neurological outcome | 65 (60) | 19 (61) | 1.000 | 56 (44) | 20 (37) | 0.417 | 18 (22) | 4 (13) | 0.425 |
30-day survival | 89 (82) | 28 (90) | 0.406 | 100 (78) | 44 (82) | 0.693 | 48 (58) | 16 (52) | 0.672 |