Beneficial response to mild therapeutic hypothermia for comatose survivors of near-hanging

Prognostic value of targeted temperature management on outcomes of hanging-induced out-of-hospital cardiac arrest: A nationwide observational study

ABSTRACT

This study aimed to evaluate the prognostic significance of targeted temperature management (TTM) on hanging-induced out-of-hospital cardiac arrest (OHCA) patients using nationwide data of South Korea.Adult hanging-induced OHCA patients from 2008 to 2018 were included in this nationwide observational study. Patients who assigned into 2 groups based on whether they did (TTM group) or did not (non-TTM group) receive TTM. Outcome measures included survival to hospital discharge and a good neurological outcome at hospital discharge.Among the 293,852 OHCA patients, 3545 patients (non-TTM, n = 2762; TTM, n = 783) were investigated. After propensity score matching for all patients, 783 matched pairs were available for analysis. We observed no significant inter-group differences in the survival to hospital discharge (non-TTM, n = 27 [3.4%] vs TTM, n = 23 [2.9%], P = .666) or good neurological outcomes (non-TTM, n = 23 [2.9%] vs TTM, n = 14 [1.8%], P = .183). In the multivariate analysis, prehospital return of spontaneous circulation (odds ratio [OR], 22.849; 95% confidence interval [CI], 11.479-45.481, P < .001) was associated with an increase in survival to hospital discharge, and age (OR, 0.971; 95% CI, 0.944-0.998, P  = .035), heart disease (OR, 16.875; 95% CI, 3.028-94.036, P  = .001), and prehospital return of spontaneous circulation (OR, 133.251; 95% CI, 30.512-581.930, P < .001) were significant prognostic factors of good neurological outcome. However, TTM showed no significant association with either outcome.There were no significant differences in the survival to hospital discharge and good neurological outcomes between non-TTM and TTM groups of hanging-induced OHCA patients.

Predictors of Futility in Near-Hanging and Therapeutic Hypothermia

Favorable neurologic outcomes have been reported in near-hanging (NH) victims treated with therapeutic hypothermia (TH), but variable methods and small samples sizes limit interpretability. This study examines the relationship between clinical predictors, TH, and outcomes in NH patients. A risk profile was created by examining relationships between variables. Categorical predictors were assessed with chi-square tests and continuous variables were assessed with t-tests. Logistic regression was conducted to evaluate the unique effect of TH. Thirty-seven NH patients were treated, 22 with cardiac arrest (CA). Poor outcome was significantly associated with age, Glasgow Coma Scale-Motor (GCS-M), pupillary response, and out-of-hospital CA (OHCA) (p's < 0.02). Patients with poor neurologic outcomes were older (M = 40.2 vs. M = 27.6) and had lower GCS-M scores (M = 1.1 vs. M = 4.1). Poor outcome probability was 76% in patients with GCS-M <3, 100% with nonreactive pupils, and 72.1% with OHCA. TH was associated with a worse outcome overall that was not significant after adjusting for GCS-M. Our study demonstrates no impact of TH on NH outcome when controlling for variables associated with poor outcome and relative certainty of poor outcome with CA, GCS-M 1, and nonreactive pupils. Study findings could assist in decisions on the utilization of TH.

EAST Multicenter Trial on targeted temperature management for hanging-induced cardiac arrest

BACKGROUND

We sought to determine the outcome of suicidal hanging and the impact of targeted temperature management (TTM) on hanging-induced cardiac arrest (CA) through an Eastern Association for the Surgery of Trauma (EAST) multicenter retrospective study.

METHODS

We analyzed hanging patient data and TTM variables from January 1992 to December 2015. Cerebral performance category score of 1 or 2 was considered good neurologic outcome, while cerebral performance category score of 3 or 4 was considered poor outcome. Classification and Regression Trees recursive partitioning was used to develop multivariate predictive models for survival and neurologic outcome.

RESULTS

A total of 692 hanging patients from 17 centers were analyzed for this study. Their overall survival rate was 77%, and the CA survival rate was 28.6%. The CA patients had significantly higher severity of illness and worse outcome than the non-CA patients. Of the 175 CA patients who survived to hospital admission, 81 patients (46.3%) received post-CA TTM. The unadjusted survival of TTM CA patients (24.7% vs 39.4%, p < 0.05) and good neurologic outcome (19.8% vs 37.2%, p < 0.05) were worse than non-TTM CA patients. However, when subgroup analyses were performed between those with an admission Glasgow Coma Scale score of 3 to 8, the differences between TTM and non-TTM CA survival (23.8% vs 30.0%, p = 0.37) and good neurologic outcome (18.8% vs 28.7%, p = 0.14) were not significant. Targeted temperature management implementation and post-CA management varied between the participating centers. Classification and Regression Trees models identified variables predictive of favorable and poor outcome for hanging and TTM patients with excellent accuracy.

CONCLUSION

Cardiac arrest hanging patients had worse outcome than non-CA patients. Targeted temperature management CA patients had worse unadjusted survival and neurologic outcome than non-TTM patients. These findings may be explained by their higher severity of illness, variable TTM implementation, and differences in post-CA management. Future prospective studies are necessary to ascertain the effect of TTM on hanging outcome and to validate our Classification and Regression Trees models.

LEVEL OF EVIDENCE

Therapeutic study, level IV; prognostic study, level III.

Neurologic outcome of comatose survivors after hanging: a retrospective multicenter study

PURPOSE

The aim of this study is to identify the neurologic outcome of hanging patients and prognostic factors.

MATERIALS AND METHODS

We retrospectively investigated comatose hanging patients who arrived at the emergency departments (EDs) of twelve academic tertiary care centers during a period of seven years (2006-2012). Patients were analyzed separately according to whether out-of-hospital cardiac arrest (OHCA) occurred or not. The neurologic outcome was evaluated using the Cerebral Performance Category (CPC) at the time of hospital discharge.

RESULTS

A total of 1118 patients were admitted to the ED after hanging attempts. There were 159 comatose patients who did not experience OHCA. Twelve (7.5%) of 159 patients were discharged from the hospital with a poor neurologic outcome (CPC 3-5). These 12 patients received only conservative management without therapeutic hypothermia. On multivariate logistic regression analysis, mental state upon ED arrival and arterial pH were predicting factors for poor prognosis. One hundred twenty-one patients suffered OHCA and experienced restored spontaneous circulation after cardiopulmonary resuscitation. Among them, only five (4.1%) patients recovered consciousness to the level of CPC 1-2. The initial arterial pH and HCO3(-) were prognostic factors in hanging patients with OHCA.

CONCLUSIONS

Even though cardiac arrest did not occur after hanging injuries, 7.5% of patients could not recover consciousness. Therapeutic hypothermia should be considered for such patients. If OHCA occurred after the hanging injury, the proportion of patients with good neurologic outcome was very low at 4.1%.

Therapeutic hypothermia for acute brain injuries

Therapeutic hypothermia, recently termed target temperature management (TTM), is the cornerstone of neuroprotective strategy. Dating to the pioneer works of Fay, nearly 75 years of basic and clinical evidence support its therapeutic value. Although hypothermia decreases the metabolic rate to restore the supply and demand of O₂, it has other tissue-specific effects, such as decreasing excitotoxicity, limiting inflammation, preventing ATP depletion, reducing free radical production and also intracellular calcium overload to avoid apoptosis. Currently, mild hypothermia (33°C) has become a standard in post-resuscitative care and perinatal asphyxia. However, evidence indicates that hypothermia could be useful in neurologic injuries, such as stroke, subarachnoid hemorrhage and traumatic brain injury. In this review, we discuss the basic and clinical evidence supporting the use of TTM in critical care for acute brain injury that extends beyond care after cardiac arrest, such as for ischemic and hemorrhagic strokes, subarachnoid hemorrhage, and traumatic brain injury. We review the historical perspectives of TTM, provide an overview of the techniques and protocols and the pathophysiologic consequences of hypothermia. In addition, we include our experience of managing patients with acute brain injuries treated using endovascular hypothermia.

Outcomes of patients admitted for hanging injuries with decreased consciousness but without cardiac arrest

OBJECTIVE

The objective of this study is to provide appropriate treatment of patients who showed decreased mentality but did not suffer cardiac arrest (CA) from hanging injury, from reviewing the characteristics and analyzing the outcomes in such patients.

METHODS

A retrospective review of victims with decreased mentality but without CA due to hanging presenting to 2 tertiary general hospitals between January 2005 and August 2011 was performed. Treatments and examinations were evaluated, and the outcomes were assessed by cerebral performance category at hospital discharge.

RESULTS

A total of 21 patients were included, and their initial Glasgow Coma Scale scores were between 3 and 11. No one received therapeutic hypothermia, but all regained consciousness spontaneously and were discharged with cerebral performance category 1. They received only conservative treatment such as respiratory care, fever control, and inotropic use. Computed tomography and magnetic resonance imaging studies revealed no definite abnormality if the patient did not show abnormal symptom and sign.

CONCLUSION

Unconscious patients without CA from hanging could recover consciousness through conservative treatment.

Brain resuscitation in the drowning victim

Drowning is a leading cause of accidental death. Survivors may sustain severe neurologic morbidity. There is negligible research specific to brain injury in drowning making current clinical management non-specific to this disorder. This review represents an evidence-based consensus effort to provide recommendations for management and investigation of the drowning victim. Epidemiology, brain-oriented prehospital and intensive care, therapeutic hypothermia, neuroimaging/monitoring, biomarkers, and neuroresuscitative pharmacology are addressed. When cardiac arrest is present, chest compressions with rescue breathing are recommended due to the asphyxial insult. In the comatose patient with restoration of spontaneous circulation, hypoxemia and hyperoxemia should be avoided, hyperthermia treated, and induced hypothermia (32-34 °C) considered. Arterial hypotension/hypertension should be recognized and treated. Prevent hypoglycemia and treat hyperglycemia. Treat clinical seizures and consider treating non-convulsive status epilepticus. Serial neurologic examinations should be provided. Brain imaging and serial biomarker measurement may aid prognostication. Continuous electroencephalography and N20 somatosensory evoked potential monitoring may be considered. Serial biomarker measurement (e.g., neuron specific enolase) may aid prognostication. There is insufficient evidence to recommend use of any specific brain-oriented neuroresuscitative pharmacologic therapy other than that required to restore and maintain normal physiology. Following initial stabilization, victims should be transferred to centers with expertise in age-specific post-resuscitation neurocritical care. Care should be documented, reviewed, and quality improvement assessment performed. Preclinical research should focus on models of asphyxial cardiac arrest. Clinical research should focus on improved cardiopulmonary resuscitation, re-oxygenation/reperfusion strategies, therapeutic hypothermia, neuroprotection, neurorehabilitation, and consideration of drowning in advances made in treatment of other central nervous system disorders.

Therapeutic Hypothermia after Perioperative Cardiac Arrest in Cardiac Surgical Patients

BACKGROUND: Therapeutic hypothermia (TH) has been established as an effective treatment for preserving neurological function after out of hospital cardiac arrest (CA). Use of TH has been limited in cardiac surgery patients in particular because of concern about adverse effects such as hemorrhage and dysrhythmia. Little published data describe efficacy or safety of TH in cardiac surgical patients who suffer unintentional CA. However, the benefits of TH are such as may suggest clinical equipoise, even in this high risk patient population. OBJECTIVE: To report a series of three patients in our institution's cardiac surgery intensive care unit who suffered unintentional CA within 48 hours of cardiac surgery and were treated with TH. METHODS: After institutional review board approval, study patients were identified by diagnosis of undesired intraoperative CA or arrest on ICU days 1-2, as well as having documented TH. The institution's electronic medical record and the Society of Thoracic Surgeons database were retrospectively reviewed for demographic information, comorbid diagnoses, surgical procedure, and outcomes including hemorrhage, re-warming dysrhythmias, infection, in-hospital mortality, and neurologic outcome were assessed. TH was initiated and monitored using active cooling pads according to written institutional protocol. RESULTS: Four patients received TH after perioperative arrest. One patient was inadequately cooled and had massive surgical bleeding, and was therefore excluded from this review. The remaining three patients had a predicted mortality of 14.6% (±13.3) based on Euroscore calculation, and were cooled for 17.6±4.0 hours after CA. Coagulopathy, hypovolemia, severe electrolyte abnormalities, and re-warming dysrhythmias were not identified in any patient. 2 patients were discharged home and 1 was discharged to a long-term care facility. CONCLUSION: Herein we report the safe and successful use of TH after unintentional perioperative CA in 3 cardiac surgery patients. These data suggest that further investigation of this therapy may be warranted given the potential benefit and apparent safety in a small series.

Therapeutic hypothermia for a comatose survivor of near-hanging

Therapeutic hypothermia is recommended for comatose survivors of cardiac arrest. Therapeutic hypothermia ameliorates multiple pathophysiologic mechanisms involved in ischemia-reperfusion injury, which may occur after cardiac arrest and near-hanging. Therapeutic hypothermia has not been prospectively studied in near-hanging. Victims of near-hanging suffer from strangulation with cerebral ischemia and resultant reperfusion injury rather than a fatal cervical spine injury. We report a case where therapeutic hypothermia was applied to a comatose survivor of near-hanging. A 41-year-old man presented with coma following attempted suicide by hanging. The patient underwent 24 hours of mild therapeutic hypothermia. The patient was discharged without neurologic sequelae and a Modified Rankin Scale of 0 (back to his baseline status). We present a case where therapeutic hypothermia was used safely and successfully in a patient without cardiac arrest but still in coma after attempted suicide by hanging. No randomized controlled trials on therapeutic hypothermia for comatose survivors of near-hanging victims have been published. However, in the absence of better evidence, it seems reasonable to consider hypothermia treatment in comatose near-hanging victims until more evidence can be obtained.