Use of target temperature management after cardiac arrest in Germany – A nationwide survey including 951 intensive care units

[Procedure after successful cardiopulmonary resuscitation-Cooling or no more cooling?]

Approximately 84 out of 100,000 inhabitants in Europe suffer from an out of hospital cardiac arrest (OHCA) each year. The mortality after cardiac arrest (CA) is high and is particularly determined by the predominant cardiogenic shock condition and hypoxic ischemic encephalopathy. For almost two decades hypothermic temperature control was the only neuroprotective intervention recommended in guidelines for postresuscitation care; however, recently published studies failed to demonstrate any improvement in the neurological outcome with hypothermia in comparison to strict normothermia in postresuscitation treatment. According to the European Resuscitation Council (ERC) and European Society of Intensive Care Medicine (ESICM) guidelines published in 2022, unconscious adults after CA should be treated with temperature management and avoidance of fever; however, many questions remain open regarding the optimal target temperature, the cooling methods and the optimal duration. Despite these currently unanswered questions, a structured and high-quality postresuscitation care that includes a targeted temperature management should continue to be provided for all patients in the postresuscitation phase, independent of the selected target temperature. Furthermore, fever avoidance remains an important component of postresuscitation care.

Management of comatose survivors of out-of-hospital cardiac arrest in Europe: current treatment practice and adherence to guidelines. A joint survey by the Association for Acute CardioVascular Care (ACVC) of the ESC, the European Resuscitation Council (ERC), the European Society for Emergency Medicine (EUSEM), and the European Society of Intensive Care Medicine (ESICM)

AIMS

International guidelines give recommendations for the management of comatose out-of-hospital cardiac arrest (OHCA) survivors. We aimed to investigate adherence to guidelines and disparities in the treatment of OHCA in hospitals in Europe.

METHODS AND RESULTS

A web-based, multi-institutional, multinational survey in Europe was conducted using an electronic platform with a predefined questionnaire developed by experts in post-resuscitation care. The survey was disseminated to all members of the societies via email, social media, websites, and newsletters in June 2021. Of 252 answers received, 237 responses from different units were included and 166 (70%) were from cardiac arrest centres. First-line vasopressor used was noradrenaline in 195 (83%) and the first-line inotrope was dobutamine in 148 (64%) of the responses. Echocardiography is available 24/7 in 204 (87%) institutions. Targeted temperature management was used in 160 (75%) institutions for adult comatose survivors of OHCA with an initial shockable rhythm. Invasive or external cooling methods with feedback were used in 72 cardiac arrest centres (44%) and 17 (24%) non-cardiac arrest centres (P < 0.0003). A target temperature between 32 and 34°C was preferred by 46 centres (21%); a target between 34 and 36°C by 103 centres (52%); and <37.5°C by 35 (16%). Multimodal neuroprognostication was poorly implemented and a follow-up at 3 months after discharge was done in 71 (30%) institutions.

CONCLUSION

Post-resuscitation care is not well established and varies among centres in European hospitals. Cardiac arrest centres have a higher coherence with guidelines compared with respondents from non-cardiac arrest centres. The overall inconsistency in approaches and deviation from recommendations could be a focus for improvement.

Temperature control in adults after cardiac arrest: a survey of current clinical practice in Germany

BACKGROUND

Temperature control is recommended after out of hospital cardiac arrest (OHCA) by international guidelines. This survey aimed to investigate current clinical practice and areas of uncertainty.

METHODS

Online survey targeting members of three medical emergency and critical care societies in Germany (April 21-June 6, 2022) assessing post-cardiac arrest temperature control management.

RESULTS

Of 341 completed questionnaires 28% (n = 97) used temperature control with normothermic target and 72% (n = 244) temperature control with hypothermic target. The definition of fever regarding patients with cardiac arrest ranged from ≥ 37.7 to 39.0 °C. Temperature control was mainly started in the ICU (80%, n = 273) and most commonly core cooling (74%, n = 254) and surface cooling (39%, n = 134) with feedback were used. Temperature control was maintained for 24 h in 18% (n = 61), 48 h in 28% (n = 94), 72 h in 42% (n = 143) and longer than 72 h in 13% (n = 43). 7% (n = 24) were using different protocols for OHCA with initial shockable and non-shockable rhythm. Additional 14% (n = 48) were using different temperature control protocols after in-hospital cardiac arrest (IHCA) compared with OHCA. Overall, 37% (n = 127) changed practice after the publication of the ERC-2021 guidelines and 33% (n = 114) after the recent publication of the revised ERC-ESICM guideline on temperature control.

CONCLUSIONS

One-third of the respondents changed clinical practice since recent guideline update. However, a majority of physicians further trusts in temperature control with a hypothermic target. Of interest, 14% used different temperature control strategies after IHCA compared with OHCA and 7% for shockable and non-shockable initial rhythm. A more individualized approach in post resuscitation care may be warranted.

Repolarization and ventricular arrhythmia during targeted temperature management post cardiac arrest

BACKGROUND

Targeted temperature management (TTM) following out-of-hospital cardiac arrest (OHCA) prolongs the QT-interval but our knowledge of different temperatures and risk of arrhythmia is incomplete.

OBJECTIVE

To assess whether the QTc, QT-peak (QTp) and T-peak to T-end interval (TpTe) may be useful markers of ventricular arrhythmia in contemporary post cardiac arrest treatment.

METHODS

An ECG-substudy of the TTM-trial (TTM at 33 °C vs. 36 °C) with serial ECGs from 680 (94%) patients. Bazett's (B) and Fridericia's (F) formula were used for heart rate correction of the QT, QTp and TpTe. Ventricular arrhythmia (VT/VF) were registered during the first three days of post cardiac arrest care.

RESULTS

The QT, QTc and QTp intervals were prolonged more at 33 °C compared to 36 °C and restored to similar and lower levels after rewarming. The TpTe-interval remained between 92-100 ms throughout TTM in both groups. The QTc intervals were associated with ventricular arrhythmia, but not after adjustment for cardiac arrest characteristics. The QTp-interval was not associated with risk of ventricular arrhythmia. Heart rate corrected TpTe-intervals were associated with higher risk of arrhythmia (Odds ratio (OR): TpTe(B): 1.12 (1.02-1.23, p = 0.01 TpTe(F): 1.12 (1.02-1.23, p = 0.02) per 20 ms). Further a prolonged TpTe-interval ≥ 90 ms was consistently associated with higher risk (OR_adjusted: TpTe(B): 2.05 (1.25-3.37), p < 0.01, TpTe(F): 2.14 (1.32-3.49), p < 0.01).

CONCLUSIONS

TTM prolongs the QT-interval by prolongation of the QTp-interval without association to increased risk. The TpTe-interval is not significantly affected by core temperature, but heart rate corrected TpTe intervals are robustly associated with risk of ventricular arrhythmia.

TRIAL REGISTRATION

The TTM-trial is registered and accessible at ClinicalTrials.gov (Identifier: NCT01020916).

Importance of acute cardiac care registries at the national level

Improving organization and patient care quality in intensive care units is increasingly important as intensive care unit diagnostic and therapeutic procedures account for a growing proportion of hospital services. We identified the lack of comprehensive national and international registries available in the contemporary literature. This paper aims to describe and analyze cardiac intensive care unit (CICU) network at the national level in Croatia and its comparison with more developed countries. Thirty-four representatives from all Croatian acute hospitals (response rate of 100%) filled in a web based questionnaire on CICU organization and competence during September and October 2016. Organization and available technical procedures for health care in general, and especially in very expensive CICU treatment, highly depends on gross domestic product (GDP) per capita. That is why one could expect that Croatia, with the second lowest GDP among European Union countries and 4.7 CICU per million inhabitants will have worse results in this field in comparison with most of these countries. Results such as one nurse responsible for a mean of 2.7 CICU patients, 52% of cardiologists among physicians during working hours but 37% during night shifts, 24/7 transesophageal echocardiography in only 26.5% of CICUs, one-third without therapeutic hypothermia, and 23.5% without extracorporeal membrane oxygenation treatment are some of these results, revealing much room for improvement. This representative, nationwide sample of Croatian CICUs also demonstrated considerable variation of key elements of structures with respect to hospital size, academic status and financial issues, as well as a trend towards current guidelines. This kind of investigation is very important for proposing standards, reimbursement master plan, or quality assessment of the national health system.

The current temperature: A survey of post-resuscitation care across Australian and New Zealand intensive care units

Aim

Targeted temperature management (TTM) in post-resuscitation care has changed dramatically over the last two decades. However, uptake across Australian and New Zealand (NZ) intensive care units (ICUs) is unclear. We aimed to describe post-resuscitation care in our region, with a focus on TTM, and to gain insights into clinician's opinions about the level of evidence supporting TTM.

Methods

In December 2017, we sent an online survey to 163 ICU medical directors in Australia (n ​= ​141) and NZ (n ​= ​22).

Results

Sixty-one ICU medical directors responded (50 from Australia and 11 from NZ). Two respondents were excluded from analysis as their Private ICUs did not admit post-arrest patients. The majority of remaining respondents stated their ICU followed a post-resuscitation care clinical guideline (n ​= ​41/59, 70%). TTM was used in 57 (of 59, 97%) ICUs, of these only 64% had a specific TTM clinical guideline/policy and there was variation in the types of patients treated, temperatures targeted (range ​= ​33-37.5 ​°C), methods for cooling and duration of cooling (range ​= ​12-72 ​h). The majority of respondents stated that their ICU (n ​= ​45/57, 88%) changed TTM practice following the TTM trial: with 28% targeting temperatures >36 ​°C, and 23 (of 46, 50%) respondents expressed concerns with current level of evidence for TTM. Only 38% of post-resuscitation guidelines included prognostication procedures, few ICUs reported the use of electrophysiological tests.

Conclusions

In Australian and New Zealand ICUs there is widespread variation in post-resuscitation care, including TTM practice and prognostication. There also seems to be concerns with current TTM evidence and recommendations.

Prehospital cooling to improve successful targeted temperature management after cardiac arrest: A randomized controlled trial

RATIONALE

Targeted temperature management (TTM) improves survival with good neurological outcome after out-of-hospital cardiac arrest (OHCA), but is delivered inconsistently and often with delay.

OBJECTIVE

To determine if prehospital cooling by paramedics leads to higher rates of 'successful TTM', defined as achieving a target temperature of 32-34°C within 6h of hospital arrival.

METHODS

Pragmatic RCT comparing prehospital cooling (surface ice packs, cold saline infusion, wristband reminders) initiated 5min after return of spontaneous circulation (ROSC) versus usual resuscitation and transport. The primary outcome was rate of 'successful TTM'; secondary outcomes were rates of applying TTM in hospital, survival with good neurological outcome, pulmonary edema in emergency department, and re-arrest during transport.

RESULTS

585 patients were randomized to receive prehospital cooling (n=279) or control (n=306). Prehospital cooling did not increase rates of 'successful TTM' (30% vs 25%; RR, 1.17; 95% confidence interval [CI] 0.91-1.52; p=0.22), but increased rates of applying TTM in hospital (68% vs 56%; RR, 1.21; 95%CI 1.07-1.37; p=0.003). Survival with good neurological outcome (29% vs 26%; RR, 1.13, 95%CI 0.87-1.47; p=0.37) was similar. Prehospital cooling was not associated with re-arrest during transport (7.5% vs 8.2%; RR, 0.94; 95%CI 0.54-1.63; p=0.83) but was associated with decreased incidence of pulmonary edema in emergency department (12% vs 18%; RR, 0.66; 95%CI 0.44-0.99; p=0.04).

CONCLUSIONS

Prehospital cooling initiated 5min after ROSC did not increase rates of achieving a target temperature of 32-34°C within 6h of hospital arrival but was safe and increased application of TTM in hospital.

[Preclinical use of mild therapeutic hypothermia after cardiac arrest by the emergency services in Baden-Württemberg, Germany]

BACKGROUND

During the last decade target temperature management has become an integral part of postresuscitation care. Within recent years there was a strong debate about the optimal target temperature, which might have effects on the preclinical induction of hypothermia. The present investigation focuses on the use of mild therapeutic hypothermia by emergency services in the state of Baden-Württemberg (Germany) and compares it to results of a prior study in 2008.

METHODS

Between April and August 2014 a questionnaire was sent to all senior emergency physicians of emergency services in Baden Württemberg. The survey period was April to August of 2014. Parts of the questionnaire were similar to a previous one in 2008, to ensure comparability to the former data; other parts were added to set new focuses. The data were analyzed in anonymized form.

RESULTS

The response rate was 72.4% (97/134). Of the 97 sites which responded to the questionnaire significantly more use preclinical hypothermia, compared to 2008 (72.2% [70/97] vs. 41.7%); 62.9% (44/70) declare cooling resuscitated patients routinely (vs. 17.7% in 2008). Cold infusions (85.7%), icepacks (64.3%), passive cooling (37.1%), nasal cooling (2.9%) and cooling caps (1.4%) are used (multiple naming was possible). Sites that did not use mild therapeutic hypothermia stated the following reasons: lack of equipment, short transport time and missing data for the intervention. Four sites reported on complications with therapeutic hypothermia.

CONCLUSION

The present investigation shows an increased use of preclinical cooling after cardiopulmonary resuscitation as compared to 2008. Therefore, recent discussions concerning the optimal target temperature in postresuscitation care did not result in a waiving of preclinical therapeutic strategies in Baden-Württemberg. The emergency services sites/locations estimated the complication rates of mild therapeutic hypothermia as very low. Lack of equipment seems to be the main reason to refuse the preclinical use of therapeutic hypothermia. In conclusion, preclinical mild therapeutic hypothermia has become an integral part in the standard care of resuscitated patients in Baden-Württemberg.

A survey on general and temperature management of post cardiac arrest patients in large teaching and university hospitals in 14 European countries-The SPAME trial results

INTRODUCTION

International guidelines recommend a bundle of care, including targeted temperature management (TTM), in post cardiac arrest survivors. Aside from a few small surveys in different European countries, adherence to the European Resuscitation Council (ERC) and European Society of Intensive Care Medicine (ESICM) recommendations are unknown.

METHODS

This international European telephone survey was conducted to provide an overview of current clinical practice of post cardiac arrest management with a main focus on TTM. We targeted large teaching and university hospitals within Europe as leading facilities and key opinion leaders in the field of post cardiac arrest care. Selected national principal investigators conducted the survey, which was based on a predefined questionnaire, between December 2014 and March 2015, before the publication of the ERC Guidelines 2015.

RESULTS

The return rate was 94% from 268 participating intensive care units (ICU). The majority had a predefined standard operating procedure (SOP) protocol for post cardiac arrest patients. Altogether, 68% of the ICUs provided TTM at a target temperature of 32-34°C for 24h, and 33% had changed the target temperature to 36°C. The minority provided a written SOP for neurological prognostication, which was generally initiated 72h after return of spontaneous circulation (ROSC). Electroencephalography and somatosensory evoked potentials were used by most ICUs for early prognostication. Treating more than fifty patients a year was significantly associated with providing written SOPs for TTM and prognostication (p<0.01), as well as the use of a computer feedback device (p=0.03) for TTM.

CONCLUSION

This international European telephone survey revealed a high rate of implementation of TTM in post cardiac arrest patients in university and teaching hospitals. Most participants also provided a SOP, but only a minority had a SOP for neurological prognostication.

Targeted temperature management after intraoperative cardiac arrest: a multicenter retrospective study

PURPOSE

Few outcome data are available about temperature management after intraoperative cardiac arrest (IOCA). We describe targeted temperature management (TTM) (32-34 °C) modalities, adverse events, and association with 1-year functional outcome in patients with IOCA.

METHODS

Patients admitted to 11 ICUs after IOCA in 2008-2013 were studied retrospectively. The main outcome measure was 1-year functional outcome.

RESULTS

Of the 101 patients [35 women and 66 men; median age, 62 years (interquartile range, 42-72)], 68 (67.3%) were ASA PS I to III and 57 (56.4%) had emergent surgery. First recorded rhythms were asystole in 44 (43.6%) patients, pulseless electrical activity in 36 (35.6%), and ventricular fibrillation/tachycardia in 20 (19.8%). Median times from collapse to cardiopulmonary resuscitation and return of spontaneous circulation (ROSC) were 0 min (0-0) and 10 min (4-20), respectively. The 30 (29.7%) patients who received TTM had an increased risk of infection (P = 0.005) but not of arrhythmia, bleeding, or metabolic/electrolyte disorders. By multivariate analysis, one or more defibrillation before ROSC was positively associated with a favorable functional outcome at 1-year (OR 3.06, 95% CI 1.05-8.95, P = 0.04) and emergency surgery was negatively associated with 1-year favorable functional outcome (OR 0.36; 95% CI 0.14-0.95, P = 0.038). TTM use was not independently associated with 1-year favorable outcome (OR 0.82; 95% CI 0.27-2.46, P = 0.72).

CONCLUSIONS

TTM was used in less than one-third of patients after IOCA. TTM was associated with infection but not with bleeding or coronary events in this setting. TTM did not independently predict 1-year favorable functional outcome after IOCA in this study.

Time-differentiated target temperature management after out-of-hospital cardiac arrest: a multicentre, randomised, parallel-group, assessor-blinded clinical trial (the TTH48 trial): study protocol for a randomised controlled trial

BACKGROUND

The application of therapeutic hypothermia (TH) for 12 to 24 hours following out-of-hospital cardiac arrest (OHCA) has been associated with decreased mortality and improved neurological function. However, the optimal duration of cooling is not known. We aimed to investigate whether targeted temperature management (TTM) at 33 ± 1 °C for 48 hours compared to 24 hours results in a better long-term neurological outcome.

METHODS

The TTH48 trial is an investigator-initiated pragmatic international trial in which patients resuscitated from OHCA are randomised to TTM at 33 ± 1 °C for either 24 or 48 hours. Inclusion criteria are: age older than 17 and below 80 years; presumed cardiac origin of arrest; and Glasgow Coma Score (GCS) <8, on admission. The primary outcome is neurological outcome at 6 months using the Cerebral Performance Category score (CPC) by an assessor blinded to treatment allocation and dichotomised to good (CPC 1-2) or poor (CPC 3-5) outcome. Secondary outcomes are: 6-month mortality, incidence of infection, bleeding and organ failure and CPC at hospital discharge, at day 28 and at day 90 following OHCA. Assuming that 50 % of the patients treated for 24 hours will have a poor outcome at 6 months, a study including 350 patients (175/arm) will have 80 % power (with a significance level of 5 %) to detect an absolute 15 % difference in primary outcome between treatment groups. A safety interim analysis was performed after the inclusion of 175 patients.

DISCUSSION

This is the first randomised trial to investigate the effect of the duration of TTM at 33 ± 1 °C in adult OHCA patients. We anticipate that the results of this trial will add significant knowledge regarding the management of cooling procedures in OHCA patients.

TRIAL REGISTRATION

NCT01689077.

An Assessment of Emergency Department Post-Cardiac Arrest Care Variation in Michigan

Implementation of postarrest care by individual physicians and systems has been slow. Deadoption, or discontinuation of therapeutic hypothermia (TH) treatment targets, after recent prospective study results has not been well reported. This study assesses practices in the early stages of postarrest care across emergency departments (EDs) in Michigan. A 27-question Internet-based survey was distributed to EDs in Michigan in September 2013. To assess changes in practice after publication of Nielsen et al., we sent follow-up questions to all original respondents a year later. Observational data and descriptive statistics are reported. From the 142 EDs identified, we excluded critical access hospitals (N = 35), free standing EDs (N = 7), EDs that transfer critical patients to tertiary centers (N = 21), and exclusive children's hospitals (N = 3). Of the remaining 76 hospitals, we received 64 (84.2%) responses. We identified 15 respondents with a protocol to specifically initiate ED TH and transfer patients to a higher level of care. The 49 remaining were mostly teaching institutions (N = 34, 69%) and gave the ED physician the ability to initiate TH (N = 40, 82%). On follow-up 12 months later, we received 33/40 (83%) responses, of which only 5 indicated formal or informal change in TH practice or target temperature. There is substantial variation in the practice of ED postarrest care and initiation of TH across the state of Michigan, but few ED TH protocols were changed in a year's time. The consequences of postarrest treatment variability at the state and ED levels are likely under-recognized as an influence on outcome variation between regions.