Abstract
-
Objective
This study investigated the relationship between post-rewarming control temperature and neurological outcomes using data from a multicenter post–cardiac arrest syndrome (PCAS) registry in Korea.
-
Methods
We retrospectively analyzed data from the PCAS registry, which prospectively enrolled out-of-hospital cardiac arrest patients with sustained return of spontaneous circulation in the emergency departments of three urban hospitals between December 2013 and April 2021. Patients who received targeted temperature management (TTM) were included. Body temperature was measured at 4-hour intervals during the first 72 hours after the initiation of TTM. The post-rewarming control temperature was defined as the body temperature measured at 72 hours after TTM initiation. The primary outcome was a favorable neurological outcome, defined as a Cerebral Performance Category score of 1–2 at 1 year, and the secondary outcome was 1-year mortality.
-
Results
Of the 1,591 patients in the registry, 289 were included in the analysis. A favorable neurological outcome occurred in 75 patients (25.9%). Patients with favorable neurological outcomes exhibited higher body temperatures at 4 hours and during the 48–72-hour period of TTM than those with unfavorable outcomes. Body temperature at 72 hours of TTM was independently associated with 1-year mortality (adjusted odds ratio [aOR], 0.56; 95% confidence interval [CI], 0.37–0.82; P=0.004), but not with favorable neurological outcomes at 1 year (aOR, 1.24; 95% CI, 0.75–2.09; P=0.399).
-
Conclusion
A lower body temperature at 72 hours after TTM was independently associated with 1-year mortality.
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Keywords: Out-of-hospital cardiac arrest; Targeted temperature management; Low body temperature
Capsule Summary
What is already known
Previous studies investigating the prognostic impact of body temperature during the post-rewarming period have mostly focused on fever (>38.0 °C) rather than low body temperature. Few clinical studies have reported the effect of post-rewarming body temperature on long-term mortality and neurological outcome.
What is new in the current study
Patients with poor prognosis had lower body temperatures than those with good prognosis during the 48–72 hour period of targeted temperature management. Furthermore, after the rewarming process was completed, patients with a poor prognosis had lower body temperatures than those with a good prognosis. Lower 72-hour temperatures were independently associated with a higher mortality rate, whereas no association was observed with favorable neurological outcomes. At 72 hours of targeted temperature management, patients with body temperatures <36.5 °C had lower survival rates than those with body temperatures ≥36.5 °C.
INTRODUCTION
Out-of-hospital cardiac arrest (OHCA) is a global public health concern due to its high incidence and poor clinical outcomes. The incidence of OHCA is approximately 34.7 per 100,000 person-years, with a survival rate of less than 10%, and fewer than 5% of patients regain sufficient neurological function to perform activities of daily living [
1,
2]. Recent post–cardiac arrest management guidelines recommend targeted temperature management (TTM) for neuroprotection in unresponsive patients following return of spontaneous circulation (ROSC). TTM consists of maintaining a body temperature of 32–36 °C for 24 hours and avoiding fever (>37.7 °C) for at least 72 hours [
3,
4].
Since TTM was incorporated into post–cardiac arrest management guidelines, several studies have examined the associations between prognosis and body temperature before, during, and after TTM. A low body temperature before TTM has been associated with multiorgan failure, higher mortality, and unfavorable neurological outcomes in several observational studies [
5–
7]. Reduced heat generation during TTM has also been independently linked to poor neurological outcomes in OHCA survivors [
8,
9]. However, the relationship between post-rewarming body temperature and clinical outcomes remains a matter of debate, with conflicting results reported.
Several previous retrospective analyses, as well as two systematic reviews and meta-analyses, have investigated the relationship between prognosis and body temperature during the post-rewarming period. Most of these studies have focused on fever (>38.0 °C) rather than low body temperature, and their findings have been inconsistent [
10–
15]. Among these, only one retrospective study reported an association between lower body temperature (rather than fever) and higher mortality and poor neurological outcomes [
13]. Therefore, current evidence remains insufficient to clarify whether low body temperature specifically influences prognosis, particularly long-term mortality.
This study aimed to investigate the association between body temperature following completion of rewarming and long-term neurological outcomes and mortality in OHCA patients.
METHODS
Ethics statement
Participation in the post–cardiac arrest syndrome (PCAS) registry was approved by the institutional review boards of Seoul National University Hospital (No. 1408-012-599), Seoul National University Bundang Hospital (No. B-1401/234-402), and Seoul Metropolitan Government Seoul National University Boramae Medical Center (No. 16-2013-157). This retrospective analysis was also approved by the institutional review boards of Seoul National University Hospital (No. H-2301-142-1400), Seoul National University Bundang Hospital (No. B-1401/234-402), and Seoul Metropolitan Government Seoul National University Boramae Medical Center (No. 20-2023-67). Informed consent was waived due to the use of deidentified data and the retrospective nature of the study.
Study design and population
This was a retrospective observational analysis using the PCAS registry (ClinicalTrials.gov identifier: NCT03695718), which prospectively registered patients with OHCA who achieved sustained ROSC and were admitted to the emergency departments (EDs) of three urban academic hospitals between December 2013 and April 2021. The inclusion criteria were age ≥18 years and receipt of TTM as recorded in the PCAS registry. Exclusion criteria included pregnancy, death in the ED, a baseline Cerebral Performance Category (CPC) score of 3–4 or an undocumented CPC score, transfer from another hospital, transfer to another hospital or facility, missing data on 1-year CPC score, or absence of body temperature data at 48 or 72 hours after TTM initiation.
TTM protocol
The TTM protocols of the three participating hospitals were consistent in terms of overall patient flow, although some details differed. At Seoul National University Hospital, TTM was initiated immediately after admission to the intensive care unit (ICU), with a target temperature of 33–36 °C. The induction and maintenance periods lasted a total of 24 hours. Rewarming was performed at a rate of 0.25 °C/hr until a temperature of 36 °C was reached, after which body temperature was maintained at 36 °C for up to 72 hours after TTM initiation.
Seoul National University Bundang Hospital aimed to reach a target temperature of 33–36 °C as rapidly as possible during induction, unless contraindicated, and to maintain that temperature for 24 hours. The rewarming process was similar to that at Seoul National University Hospital, but the controlled temperature up to 72 hours was maintained at 37 °C, in contrast to 36 °C at Seoul National University Hospital.
At Seoul Metropolitan Government Seoul National University Boramae Medical Center, TTM was initiated in the ED before ICU admission, with a target temperature of 32–36 °C. The induction and maintenance periods lasted either 24 or 48 hours, and rewarming was performed at a rate of 0.25 °C/hr, consistent with the other hospitals. The post-rewarming control temperature at the hospital was maintained at 36 °C, with strict fever avoidance, for up to 72 hours after TTM initiation.
Across all three hospitals, Arctic Sun (Medivance Corp) was primarily used for surface cooling. When the device was unavailable or patient consent for its use was not obtained, a cold blanket was used instead.
Data collection
All PCAS registry data were extracted from the clinical data warehouse systems of the participating hospitals and were entered by research coordinators or physicians at each site. The following data were collected from among the 180 variables in the PCAS registry: demographic characteristics; predisposing factors; presumed etiology; prehospital cardiopulmonary resuscitation (CPR) information; in-hospital management information; severity index (Sequential Organ Failure Assessment [SOFA] score at admission); TTM details (time interval from collapse to TTM initiation, target temperature, duration of induction and maintenance, body temperature in the ED and at 4-hour intervals during the first 72 hours after TTM initiation, and use of a surface cooling device); CPC score at 1 year; and mortality at 1 year.
The CPC assessment was conducted by research coordinators responsible for the PCAS registry, who were not blinded to the patients’ in-hospital course. Data were obtained through telephone interviews with patients or their representatives, or by reviewing electronic medical records. During the interviews, CPC scores were determined using a standardized checklist (
Suppl. 1).
We defined the post-rewarming control body temperature as the body temperature measured at 72 hours after the initiation of TTM, a time point that typically represents the completion of surface cooling using the Arctic Sun.
Outcome measures
The primary outcome was a favorable long-term neurological outcome at 1 year. Neurological outcomes were evaluated using the CPC scale, classified as follows: 1, good performance; 2, moderate disability; 3, severe disability; 4, vegetative state; and 5, brain death or death. The secondary outcome was 1-year all-cause mortality.
Statistical analysis
Continuous variables are expressed as medians with interquartile ranges (IQRs) to reflect non-normal distributions and were compared using the Wilcoxon rank sum test. Categorical variables are expressed as counts (percentages) and were compared between groups using the chi-square test.
Univariable and multivariable logistic regression analyses were conducted to examine the associations between body temperature at 72 hours after TTM initiation and 1-year outcome variables, and to identify independent predictors of neurological outcomes and mortality. Adjustments were made for confounding factors including age, sex, diabetes mellitus, witnessed arrest, bystander CPR, first monitored rhythm, ROSC achieved by emergency medical services (EMS) personnel, presumed cardiac cause, and total arrest time. These covariates were selected from variables with P<0.05 in univariable analysis, with final inclusion determined to avoid multicollinearity. Multivariable models for 1-year neurological outcomes and mortality were refined using stepwise backward elimination. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. For continuous predictors, the area under the receiver operating characteristic curve (AUROC) was computed, and corresponding cutoff values were determined.
Additionally, 1-year survival rates were compared using Kaplan-Meier survival curves. Patients were initially stratified according to the cutoff values of the identified predictors and subsequently subdivided by the predefined fever threshold of 37.7 °C. Statistical significance was evaluated using the log-rank test, followed by post hoc pairwise comparisons with Bonferroni correction among the three groups.
Comparisons among the three hospitals were performed using the Kruskal-Wallis test, followed by post hoc analysis with Bonferroni correction.
All statistical analyses were performed using R ver. 4.2.2 (R Foundation for Statistical Computing). All tests were two-sided, and P-values of <0.05 were considered statistically significant. Missing data were not imputed.
RESULTS
A total of 1,591 patients were included in the PCAS registry between December 2013 and April 2021. Among them, 600 patients met the inclusion criteria for this study. Of these 600 patients, 311 were excluded for the following reasons: (1) death in the ED (n=8); (2) baseline CPC score of 3–4 or undocumented CPC score (n=72); (3) transfer from another hospital (n=116); (4) transfer from a study hospital ED to another hospital or facility (n=6); (5) missing 1-year CPC score (n=15); and (6) missing body temperature data at 72 hours after TTM initiation (n=94). Ultimately, 289 patients were included in the final analysis (
Fig. 1).
Patients were categorized into favorable (n=75) and unfavorable (n=214) outcome groups based on their 1-year neurological outcome (
Table 1). The favorable neurological outcome group was younger (median, 52 years vs. 62 years; P=0.001) and had a lower proportion of women (17.3% vs. 33.6%, P=0.012) than the unfavorable group. In the prehospital phase, patients with favorable outcomes were more likely to have had a witnessed arrest (85.3% vs. 65.9%, P=0.002), to have received bystander CPR (69.3% vs. 50.5%, P=0.003), and to have had an initial shockable rhythm (72.0% vs. 22.9%, P<0.001). In addition, the rate of ROSC achieved by EMS personnel was significantly higher (76.0% vs. 18.3%, P<0.001), and cardiac etiology was more common (89.3% vs. 29.0%, P<0.001) in the favorable outcome group. According to the in-hospital CPR data, patients with favorable neurological outcomes had a longer interval from collapse to intubation (34 minutes vs. 29 minutes, P=0.036), a lower total epinephrine dosage (0 mg vs. 2 mg, P<0.001), a significantly shorter total low-flow time (14 minutes vs. 25.5 minutes, P<0.001), and a shorter total arrest time (19.5 minutes vs. 31 minutes, P<0.001). Regarding TTM-related variables, no significant differences were observed between the two groups in the time interval from collapse to TTM initiation, target temperature, duration of induction and maintenance, or use of surface cooling devices.
As shown in
Fig. 2A, patients with favorable 1-year neurological outcomes had higher body temperatures at ED admission than those with unfavorable outcomes. The favorable group also had higher temperatures at 0 and 4 hours after TTM initiation. No significant differences were observed between the groups at 8 to 44 hours after TTM initiation. Beginning at 48 hours and continuing until 72 hours, patients with favorable neurological outcomes consistently exhibited higher body temperatures (
Fig. 2A,
Suppl. 2). At 72 hours, the median post-rewarming control temperature was 37.1 °C (IQR, 36.5–37.5 °C) in the favorable group compared with 36.4 °C (IQR, 35.9–36.9 °C) in the unfavorable group (P<0.001) (
Suppl. 2). Despite minor interhospital variations (
Suppl. 3), the overall temperature trend remained consistent with that shown in
Fig. 2A. A similar relationship was observed between body temperature and 1-year mortality. Patients who survived for 1 year exhibited higher body temperatures during the first 4 hours, at 32 and 36 hours, and from 48 to 72 hours of TTM (except at 52 hours), compared with those who died within 1 year (
Fig. 2B,
Suppl. 4).
Univariable analysis revealed that lower body temperature at 72 hours of TTM was associated with unfavorable neurological outcomes and higher mortality. However, in multivariable analysis adjusted for confounding factors, lower body temperature at 72 hours of TTM was not associated with unfavorable neurological outcomes but remained independently associated with higher mortality (
Table 2).
Predictive factors for 1-year favorable neurological outcomes (CPC 1–2) and 1-year mortality identified through multivariable logistic regression with backward elimination are presented in
Fig. 3. Predictors of favorable neurological outcomes included initial shockable rhythm (OR, 3.81; 95% CI, 1.34–10.85; P=0.012), ROSC achieved by EMS personnel (OR, 3.03; 95% CI, 1.17–7.82; P=0.022), younger age (OR, 0.97; 95% CI, 0.95–1.00; P=0.029), shorter total arrest time (OR, 0.95; 95% CI, 0.92–0.98; P=0.003), and cardiac etiology (OR, 0.11; 95% CI, 0.04–0.35; P<0.001) (
Fig. 3A,
Suppl. 5).
Conversely, predictors of 1-year mortality included presumed noncardiac etiology (OR, 4.47; 95% CI, 2.24–8.87; P<0.001), total arrest time (OR, 1.04; 95% CI, 1.02–1.07; P=0.002), older age (OR, 1.03; 95% CI, 1.01–1.05; P<0.001), lower body temperature at 72 hours of TTM (OR, 0.53; 95% CI, 0.36–0.78; P=0.001), and absence of ROSC by EMS personnel (OR, 0.34; 95% CI, 0.16–0.73; P=0.005) (
Fig. 3B,
Suppl. 5). Receiver operating characteristic analysis showed that body temperature at 72 hours was predictive of 1-year mortality but not of 1-year favorable neurological outcome. The optimal cutoff value for body temperature at 72 hours was 36.5 °C (AUROC, 0.713) (
Suppl. 5).
Fig. 4 presents the Kaplan-Meier survival curves comparing 1-year survival according to body temperature at 72 hours of TTM. Patients with body temperatures <36.5 °C had significantly lower survival rates than those with temperatures ≥36.5 °C (P<0.001) (
Fig. 4A). When further subdivided, patients with temperatures <36.5 °C had significantly lower survival rates than those with 36.5–37.7 °C (P<0.001) or >37.7 °C (P<0.001) (
Fig. 4B–
D). When dichotomized at 37.7 °C, survival was significantly lower in the ≤37.7 °C group than in the >37.7 °C group (P=0.038) (
Fig. 4E).
DISCUSSION
In this study, we investigated the relationship between post-rewarming control temperature following TTM and clinical outcomes. During the 48–72-hour period of TTM, after completion of the rewarming process, patients with poor prognoses exhibited lower body temperatures than those with good prognoses. A lower 72-hour temperature was independently associated with higher mortality, whereas no association was observed with favorable neurological outcomes. At 72 hours of TTM, patients with body temperatures <36.5 °C had lower survival rates than those with temperatures ≥36.5 °C.
Taken together, post-rewarming control temperature was not associated with neurological outcomes but was associated with mortality. This finding may be attributable to thermoregulatory dysfunction secondary to multiorgan failure and hypoxic injury [
16], with lower body temperature reflecting compromised systemic condition, which in turn may contribute to higher mortality. Patients who developed hypothermia after TTM may have already sustained irreversible hypoxic brain injury, making further neuroprotection from TTM unlikely. This interpretation does not imply that TTM itself is ineffective; rather, the patient population in this study may not have represented the optimal candidates for TTM.
Although the exact mechanisms remain unclear, TTM has been proposed to improve neurological outcomes by reducing metabolic rate, limiting free radical production, and suppressing excitatory amino acid release, thereby mitigating secondary neuronal injury [
17,
18]. However, recent large randomized controlled trials have yielded conflicting findings [
19–
23]. The TTM-1 and TTM-2 trials reported no significant differences in mortality or neurological outcomes between hypothermia and control groups among OHCA patients [
21,
23], whereas the HYPERION trial, which enrolled both OHCA and in-hospital cardiac arrest patients with nonshockable rhythms, found improved neurological outcomes with hypothermia [
22]. These results suggest that the efficacy of TTM may vary across patient subgroups, and additional evidence is required to refine its indications. Moreover, a recent trial comparing different durations of TTM found no difference in either mortality or neurological outcome between 36 and 72 hours [
24]. In this context, we observed that a higher post-rewarming control temperature at 72 hours was associated with more favorable outcomes, while a lower temperature was correlated with increased mortality. This highlights the complexity of temperature-outcome relationships and supports the need for patient-stratified, prospective evaluation. As an observational study, our results are hypothesis-generating and warrant confirmation.
Furthermore, we identified lower body temperature at 72 hours of TTM as a predictor of increased 1-year mortality, but not of 1-year neurological outcomes. This discrepancy may indicate that post-rewarming hypothermia is more reflective of systemic deterioration than reversible neurological injury. Patients who achieved early neurological recovery during TTM may have experienced less temperature decline by 72 hours, partially explaining the lack of association with long-term neurological outcomes. In this context, body temperature at 72 hours likely functions as a marker of overall physiological status rather than as a determinant of neurological prognosis. Another possible explanation is that patients who regained consciousness during TTM may have undergone less strict temperature control because they already demonstrated favorable neurological outcomes, representing a potential limitation of our study.
Current TTM guidelines recommend avoiding fever above 37.7 °C for at least 72 hours in comatose cardiac arrest patients [
3,
4]. Based on these recommendations, we stratified patients at 72 hours using 36.5 °C as the cutoff value and 37.7 °C as an additional threshold. We found that patients with body temperatures above 37.7 °C had better survival rates than those with temperatures below 36.5 °C. Interestingly, survival among patients with temperatures above 37.7 °C was not only higher than in the <36.5 °C group but also better than in the ≤37.7 °C group. This finding is consistent with prior studies demonstrating that post-rewarming fever is associated with reduced mortality [
11–
14]. Extending these earlier findings, our results suggest that fever may be associated with improved survival, while lower body temperature correlates with increased mortality—an observation that could have clinical implications for post-TTM temperature management.
The major limitation of this study was that TTM protocols were not fully standardized across the three hospitals. The durations of induction and maintenance periods differed, and significant interhospital differences were observed, particularly between Seoul National University Hospital and Seoul Metropolitan Government Seoul National University Boramae Medical Center after Bonferroni correction in post hoc analysis (
Suppl. 6). Another protocol variation was the target temperature, although 33 °C was the most frequently selected across hospitals (
Suppl. 7), and final decisions were at the discretion of the attending physician. Despite these variations, the temperature trajectories shown in
Suppl. 3 were largely similar. Importantly, rewarming was completed by 72 hours of TTM in all hospitals, suggesting that protocol differences were unlikely to have significantly affected the observed associations between body temperature at 72 hours and outcomes. Another important limitation is that our key exposure, the post-rewarming control temperature, may partially reflect adherence to protocol rather than intrinsic physiology. Such protocol-related influence could introduce measurement bias and limit the physiologic interpretability of the observed associations. Additionally, the retrospective study design introduces inherent bias. All participating hospitals were urban academic tertiary centers treating a high proportion of critically ill patients, including those with malignancy or immunocompromised states, potentially leading to selection bias. Finally, the number of patients who underwent TTM among the total registry population was relatively small, and there were instances of missing data.
A low body temperature at 72 hours after TTM was independently associated with higher 1-year mortality. To elucidate the relationship between post-temperature control hypothermia and neurological outcomes, prospective randomized controlled trials are needed.
NOTES
-
Author contributions
Conceptualization: HP, JS, MY, HL, GJS; Data curation: HP, JL; Formal analysis: HP, JL, JS; Methodology: HP, JS, DKL, JK, GJS; Resources: HP, JS, JK; Supervision: JS, DKL; Validation: MY, HL, JK; Visualization: HP; Writing–original draft: HP, GJS; Writing–review & editing: all authors. All authors read and approved the final manuscript.
-
Conflicts of interest
Gil Joon Suh is an editorial board member of this journal, but was not involved in the peer reviewer selection, evaluation, or decision process of this article. The authors have no other conflicts of interest to declare.
-
Funding
The authors received no financial support for this study.
-
Data availability
Data analyzed in this study are available from the corresponding author upon reasonable request.
Supplementary materials
Suppl. 1.
Standardized checklist to assess Cerebral Performance Category (CPC) score (in Korean).
ceem-25-158-Suppl-1.pdf
Suppl. 3.
Comparison of body temperature during targeted temperature management across hospitals according to 1-year Cerebral Performance Category (CPC).
ceem-25-158-Suppl-3.pdf
Suppl. 6.
Comparison of duration of induction/maintaining targeted temperature according to the study hospitals.
ceem-25-158-Suppl-6.pdf
Suppl. 7.
Demographics and clinical characteristics according to 1year neurological outcome and study hospital.
ceem-25-158-Suppl-7.pdf
Fig. 1.Flow diagram of patient inclusion. PCAS, post–cardiac arrest syndrome; TTM, targeted temperature management; ED, emergency department; CPC, Cerebral Performance Category.
Fig. 2.Comparison of body temperature during targeted temperature management according to (A) 1-year Cerebral Performance Category (CPC) score and (B) 1-year mortality. *P<0.05, **P<0.01, ***P<0.001.
Fig. 3.Predictors of (A) 1-year Cerebral Performance Category (CPC) 1–2 and (B) 1-year mortality. OR, odds ratio; CI, confidence interval; ROSC, return of spontaneous circulation; EMS, emergency medical services; TTM, targeted temperature management. *P<0.05, **P<0.01, ***P<0.001.
Fig. 4.Comparison of survival rates based on body temperature (BT). Kaplan-Meier survival analyses were performed in patients with available 72-hour post-rewarming BT measurements and survival-time data (n=197). (A) <36.5 °C vs. ≥36.5°C. (B) <36.5 °C vs. 36.5–37.7 °C. (C) <36.5 °C vs. >37.7 °C. (D) <36.5 °C vs. 36.5–37.7 °C vs. >37.7 °C. (E) ≤37.7 °C vs. >37.7 °C.
Table 1.Demographics and clinical characteristics based on 1-year neurological outcomes
Table 1.
|
Characteristic |
Favorable outcome (n=75) |
Unfavorable outcome (n=214) |
P-value |
|
Age (yr) |
52 (43–62.5) |
62 (48–75) |
0.001 |
|
Female sex |
13 (17.3) |
72 (33.6) |
0.012 |
|
Body mass index (kg/m2) |
24.3 (22.6–25.8) |
22.9 (20.1–25.2) |
0.001 |
|
Predisposing factor |
|
|
|
|
Hypertension |
23 (30.7) |
87 (40.7) |
0.304 |
|
Diabetes mellitus |
5 (6.7) |
66 (30.8) |
<0.001 |
|
Prehospital CPR information |
|
|
|
|
Witnessed arrest |
64 (85.3) |
141 (65.9) |
0.002 |
|
Received bystander CPR |
52 (69.3) |
108 (50.5) |
0.003 |
|
Initial shockable rhythm |
54 (72.0) |
49 (22.9) |
<0.001 |
|
AED use by bystander before EMS personnel arrival |
3 (4.0) |
6 (2.8) |
0.899 |
|
ROSC before EMS arrival |
2 (2.7) |
9 (4.2) |
0.804 |
|
AED use by EMS personnel |
60 (80.0) |
51 (23.8) |
<0.001 |
|
Airway management by EMS personnel |
49 (65.3) |
154 (72.0) |
0.368 |
|
ROSC by EMS personnel |
57 (76.0) |
39 (18.3) |
<0.001 |
|
Time interval from collapse to ED arrival (min) |
24.0 (18.0–30.0) |
26.0 (18.5–33.0) |
0.117 |
|
Presumed cardiac cause |
67 (89.3) |
62 (29.0) |
<0.001 |
|
In-hospital CPR information |
|
|
|
|
Time interval from collapse to intubation (min) |
34 (24–39) |
29 (21–36) |
0.036 |
|
Total epinephrine dose during CPR (mg) |
0 (0–1) |
2 (1–3) |
<0.001 |
|
Extracorporeal CPR |
1 (1.3) |
4 (1.9) |
>0.999 |
|
Total no-flow time (min) |
2 (0–5) |
3 (0–7) |
0.275 |
|
Total low-flow time (min) |
14 (10–22.5) |
25.5 (18–35) |
<0.001 |
|
Total arrest time (min) |
19.5 (13–27) |
31 (20–40) |
<0.001 |
|
In-hospital management information |
|
|
|
|
Coronary angiography |
57 (76.0) |
53 (24.8) |
<0.001 |
|
Percutaneous coronary intervention |
31 (41.3) |
32 (15.0) |
<0.001 |
|
Continuous renal replacement therapy |
2 (2.7) |
32 (15.0) |
0.008 |
|
SOFA score at ICU admission |
8 (6–10) |
10 (7–12) |
<0.001 |
|
TTM information |
|
|
|
|
Time interval from collapse to TTM (hr) |
5.1 (3.4–7.7) |
5.4 (3.1–8.2) |
0.729 |
|
Targeted temperature (°C)a)
|
|
|
0.579 |
|
32 |
0 (0) |
1 (0.5) |
|
|
33 |
54 (72.0) |
147 (68.7) |
|
|
34 |
12 (16.0) |
25 (11.7) |
|
|
35 |
1 (1.3) |
7 (3.3) |
|
|
36 |
8 (10.7) |
33 (15.4) |
|
|
Duration of induction/maintenance of target temperature (hr) |
24.4 (24.0–28.9) |
24.2 (24.0–27.7) |
0.893 |
|
Use of surface cooling devices |
75 (100) |
200 (93.5) |
0.157 |
|
Location of body temperature monitorb)
|
|
|
0.395 |
|
Esophagus |
52 (69.3) |
145 (70.0) |
|
|
Bladder |
10 (13.3) |
16 (7.7) |
|
|
Rectum |
5 (6.7) |
26 (12.6) |
|
|
Other |
2 (2.7) |
3 (1.4) |
|
|
Unknown |
6 (8.0) |
17 (8.2) |
|
Table 2.ORs for body temperature at 72 hours after targeted temperature management initiation for predicting favorable neurological outcomes and mortality
Table 2.
|
Variable |
Univariable analysis |
Multivariable analysisa)
|
|
Crude OR (95% CI) |
P-value |
aOR (95% CI) |
P-value |
|
1-yr Favorable neurological outcome (CPC 1–2) |
2.07 (1.51–2.91) |
<0.001 |
1.24 (0.75–2.09) |
0.399 |
|
1-yr Mortality |
0.44 (0.32–0.60) |
<0.001 |
0.56 (0.37–0.82) |
0.004 |
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, Jongwhan Shin2,3
