Post-cardiac arrest management: more than global cooling?

Comparison of Electronic Learning Versus Lecture-based Learning in Improving Emergency Medicine Residents' Knowledge About Mild Induced Hypothermia After Cardiac Arrest

Background

The process of medical education depends on several issues such as training materials, students, professors, educational fields, and the applied technologies. The current study aimed at comparing the impacts of e-learning and lecture-based learning of mild induced hypothermia (MIH) after cardiac arrest on the increase of knowledge among emergency medicine residents.

Methods

In a pre- and post-intervention study, MIH after cardiac arrest was taught to 44 emergency medicine residents. Residents were randomly divided into 2 groups. The first group included 21 participants (lecture-based learning) and the second had 23 participants (e-learning). A 19-item questionnaire with approved validity and reliability was employed as the pretest and posttest. Then, data were analyzed with SPSS software version 17.0.

Results

There was no statistically significant difference in terms of the learning method between the test scores of the 2 groups (P = 0.977).

Conclusions

E-learning and lecture-based learning methods was effective in augmentation of residents of emergency medicine knowledge about MIH after cardiac arrest; nevertheless, there was no significant difference between these mentioned methods.

Hypothermia after cardiac arrest as a novel approach to increase survival in cardiopulmonary cerebral resuscitation: a review

Context:

The aim of this review study was to evaluate therapeutic mild hypothermia, its complications and various methods for induced mild hypothermia in patients following resuscitation after out-of-hospital cardiac arrest.

Evidence Acquisition:

Studies conducted on post-cardiac arrest cares, history of induced hypothermia, and therapeutic hypothermia for patients with cardiac arrest were included in this study. We used the valid databases (PubMed and Cochrane library) to collect relevant articles.

Results:

According to the studies reviewed, induction of mild hypothermia in patients after cardiopulmonary resuscitation would lead to increased survival and better neurological outcome; however, studies on the complications of hypothermia or different methods of inducing hypothermia were limited and needed to be studied further.

Conclusions:

This study provides strategic issues concerning the induction of mild hypothermia, its complications, and different ways of performing it on patients; using this method helps to increase patients’ neurological survival rate.

Neurologic complications of cardiac arrest

Cardiac arrest is a common and serious medical emergency affecting upwards of 450000 Americans on an annual basis. It causes a substantial strain on the physical and financial resources of the medical system. The optimal management of patients requires the close collaboration of multiple specialists, including first responders, intensivists, cardiologists, and neurologists. The role of the neurologist for the post-arrest patient is to assist in management to minimize brain injury as well as to prognosticate long-term outcomes to help guide therapy decisions of families and physicians. This review focuses on epidemiologic data, current management recommendations, clinical and ancillary testing to suggest long-term prognosis, and common complications of cardiac arrest. Particular attention has been paid to updates, including therapeutic hypothermia, since this topic was last reviewed in 1993.

Therapeutic hypothermia for out-of-hospital cardiac arrest: an update for neurosurgeons

BACKGROUND

Neurosurgeons have been familiar with the idea that hypothermia is protective against various types of brain injuries, including traumatic brain injury (TBI). Recent randomized controlled trials, however, have failed to demonstrate the efficacy of therapeutic hypothermia (TH) in patients with TBI. On the other hand, TH becomes popular in the treatment of out-of-hospital cardiac arrest (OHCA) survivors, after randomized controlled trials have shown that survival rate and functional outcome is improved with the use of TH in selected patients. We believe that knowledge on the recent progress in TH for OHCA is useful for neurosurgeons, because feedback of information obtained in the treatment of OHCA may revitalize the interest in TH for neurosurgical disorders, particularly TBI.

METHODS

A review of the literature was conducted with the use of PubMed.

RESULTS

Various cooling techniques and devices have been developed and trialed in the treatment of OHCA survivors, including prehospital cooling with bolus ice-cold saline, endovascular cooling catheters, and new generation surface cooling devices, some of which have already been known to neurosurgeons. The efficacy of these new methods and devices has been demonstrated in many preliminary studies, and phase III trials are also expected.

CONCLUSIONS

Neurosurgeons and critical care medicine physicians pursue the same goal of rescuing the brain from the secondary injury despite the difference in etiology (focal trauma vs. global ischemia), with the presumption that earlier and faster implementation of TH will result in better outcome. Thoughtful application of knowledge and techniques obtained in OHCA to TBI under a rigorously controlled situation will make a small, but significant difference in the outcome of TBI victims.

Contemporary practices in postcardiac arrest syndrome: the role of mild therapeutic hypothermia

Out-of-hospital cardiac arrest remains a major cause of mortality and morbidity despite progress in resuscitative practices. The number of survivors with severe neurological impairment at hospital discharge is similarly dismal. Recently, much attention has been directed toward the use of mild therapeutic hypothermia in the care of comatose survivors with postcardiac arrest syndrome. Recent research suggests mild hypothermia lowers mortality and improves neurological outcome after successful treatment of cardiac arrest. The current 2005 updated guidelines of International Liaison Committee on Resuscitation and European Resuscitation Council recommend the utilization of mild induced hypothermia in postresuscitation treatment. Hypothermia induction in order to avoid the pathophysiological mechanisms of euthermia and hyperthermia and subsequent complications are briefly discussed. Cooling methods, potential side effects and questions regarding implementation of therapeutic hypothermia recommendations in every day clinical practice and future investigation are also addressed.

Esophageal temperature after out-of-hospital cardiac arrest: an observational study

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is a significant cause of death and severe neurological disability. The only post-return of spontaneous circulation (ROSC) therapy shown to increase survival is mild therapeutic hypothermia (MTH). The relationship between esophageal temperature post OHCA and outcome is still poorly defined.

METHODS

Prospective observational study of all OHCA patients admitted to a single centre for a 14-month period (1/08/2008 to 31/09/2009). Esophageal temperature was measured in the Emergency Department and Intensive Care Unit (ICU). Selected patients had pre-hospital temperature monitoring. Time taken to reach target temperature after ROSC was recorded, together with time to admission to the Emergency Department and ICU.

RESULTS

164 OHCA patients were included in the study. 105 (64.0%) were pronounced dead in the Emergency Department. 59 (36.0%) were admitted to ICU for cooling; 40 (24.4%) died in ICU and 19 (11.6%) survived to hospital discharge. Patients who achieved ROSC and had esophageal temperature measured pre-hospital (n=29) had a mean pre-hospital temperature of 33.9 degrees C (95% CI 33.2-34.5). All patients arriving in the ED post OHCA had a relatively low esophageal temperature (34.3 degrees C, 95% CI 34.1-34.6). Patients surviving to hospital discharge were warmer on admission to ICU than patients who died in hospital (35.7 degrees C vs 34.3 degrees C, p<0.05). Patients surviving to hospital discharge also took longer to reach T(targ) than non-survivors (2h 48min vs 1h 32min, p<0.05).

CONCLUSIONS

Following OHCA all patients have esophageal temperatures below normal in the pre-hospital phase and on arrival in the Emergency Department. Patients who achieve ROSC following OHCA and survive to hospital discharge are warmer on arrival in ICU and take longer to reach target MTH temperatures compared to patients who die in hospital. The mechanisms of action underlying esophageal temperature and survival from OHCA remain unclear and further research is warranted to clarify this relationship.

Mild therapeutic hypothermia shortens intensive care unit stay of survivors after out-of-hospital cardiac arrest compared to historical controls

Introduction

Persistent coma is a common finding after cardiac arrest and has profound ethical and economic implications. Evidence suggests that therapeutic hypothermia improves neurological outcome in these patients. In this analysis, we investigate whether therapeutic hypothermia influences the length of intensive care unit (ICU) stay and ventilator time in patients surviving out-of-hospital cardiac arrest.

Methods

A prospective observational study with historical controls was conducted at our medical ICU. Fifty-two consecutive patients (median age 62.6 years, 43 males, 34 ventricular fibrillation) submitted to therapeutic hypothermia after out-of-hospital cardiac arrest were included. They were compared with a historical cohort (n = 74, median age 63.8 years, 53 males, 43 ventricular fibrillation) treated in the era prior to hypothermia treatment. All patients received the same standard of care. Neurological outcome was assessed using the Pittsburgh cerebral performance category (CPC) score. Univariate analyses and multiple regression models were used.

Results

In survivors, therapeutic hypothermia and baseline disease severity (Acute Physiology and Chronic Health Evaluation II [APACHE II] score) were both found to significantly influence ICU stay and ventilator time (all P < 0.01). ICU stay was shorter in survivors receiving therapeutic hypothermia (median 14 days [interquartile range (IQR) 8 to 26] versus 21 days [IQR 15 to 30] in the control group; P = 0.017). ICU length of stay and time on ventilator were prolonged in patients with CPC 3 or 4 compared with patients with CPC 1 or 2 (P = 0.003 and P = 0.034, respectively). Kaplan-Meier analysis showed improved probability for 1-year survival in the hypothermia group compared with the controls (log-rank test P = 0.013).

Conclusion

Therapeutic hypothermia was found to significantly shorten ICU stay and time of mechanical ventilation in survivors after out-of-hospital cardiac arrest. Moreover, profound improvements in both neurological outcome and 1-year survival were observed.