Induced hypothermia after cardiac arrest in trauma patients: a case series

Neurological outcomes after traumatic cardiopulmonary arrest: a systematic review

Background

Despite appropriate care, most patients do not survive traumatic cardiac arrest, and many survivors suffer from permanent neurological disability. The prevalence of non-dismal neurological outcomes remains unclear.

Objectives

The aim of the current review is to summarize and assess the quality of reporting of the neurological outcomes in traumatic cardiac arrest survivors.

Data sources

A systematic review of Embase, Medline, PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and ProQuest databases was performed from inception of the database to July 2020.

Study eligibility criteria

Observational cohort studies that reported neurological outcomes of patients surviving traumatic cardiac arrest were included.

Participants and interventions

Patients who were resuscitated following traumatic cardiac arrest.

Study appraisal and synthesis methods

The quality of the included studies was assessed using ROBINS-I (Risk of Bias in Non-Randomized Studies - of Interventions) for observational studies.

Results

From 4295 retrieved studies, 40 were included (n=23 644 patients). The survival rate was 9.2% (n=2168 patients). Neurological status was primarily assessed at discharge. Overall, 45.8% of the survivors had good or moderate neurological recovery, 29.0% had severe neurological disability or suffered a vegetative state, and 25.2% had missing neurological outcomes. Seventeen studies qualitatively described neurological outcomes based on patient disposition and 23 studies used standardized outcome scales. 28 studies had a serious risk of bias and 12 had moderate risk of bias.

Limitations

The existing literature is characterized by inadequate outcome reporting and a high risk of bias, which limit our ability to prognosticate in this patient population.

Conclusions or implications of key findings

Good and moderate neurological recoveries are frequently reported in patients who survive traumatic cardiac arrest. Prospective studies focused on quality of survivorship in traumatic arrest are urgently needed.

Level of evidence

Systematic review, level IV.

PROSPERO registration number

CRD42020198482.

Therapeutic Hypothermia and Targeted Temperature Management for Traumatic Arrest and Surgical Patients

Therapeutic hypothermia (TH) and targeted temperature management (TTM) have been shown to improve outcomes in survivors of cardiac arrest, but prior research has excluded trauma and postoperative patients. We sought to determine whether TH/TTM is safe in trauma and surgical patients. A retrospective cohort study was conducted at a single level I trauma center reviewing adults presenting as a traumatic arrest or cardiac arrest in the postoperative period with a Glasgow Coma Scale <8 after return of circulation who were treated with either TH or TTM. Neurological recovery is considered favorable if a patient was discharged following commands. A total of 32 cardiac arrest patients were included in the study, 14 of whom were treated with TH and 18 with TTM protocols, with goal temperatures of 33°C and 36°C, respectively. Mean age of the cohort was 60 ± 13, with 26 (81%) men. There were 18 trauma patients and 14 postoperative patients. Complications included pneumonia (13%), sepsis (6%), bleeding requiring transfusion (22%), arrhythmias (6%), and seizures (9%), which are similar to prior published series. Overall survival to discharge was 41% (n = 13), and all survivors had favorable neurological recovery. Traumatic arrest and perioperative cardiac arrest patients previously excluded from TH/TTM studies appear to have an acceptable incidence of complications compared with standard TH/TTM patients.

Successful Use of Targeted Temperature Management After Repair of Myocardial Rupture from Blunt Chest Trauma: A Case Report

Targeted temperature management (TTM) improves survival and neurological outcome after nontraumatic cardiac arrest. However, TTM is not used widely after traumatic cardiac arrest because of concerns that it might exacerbate bleeding. We report the use of postarrest TTM after repair of blunt myocardial rupture. A 48-year-old man was admitted after being rescued from a major traffic accident by the local emergency service. Focused sonography showed pericardial fluid without cardiac tamponade. Computed tomography showed a large hematoma in the anterior mediastinum associated with hemopericardium. The patient developed cardiac arrest during the operative preparations. Repeat bedside sonography revealed a large pericardial effusion and signs of cardiac tamponade. Spontaneous circulation was restored after ultrasound-guided pericardiocentesis. His Glasgow Coma Scale score was 3. The patient was transported promptly to the operating room and underwent median sternotomy without cardiopulmonary bypass. A rupture of the junction of the superior vena cava/right atrium and left atrial appendage was detected and was closed by direct suturing. Immediately after return to the intensive care unit, we performed TTM (target body temperature 34.5°C) using a surface-cooling device at 4 hours postarrest. TTM was maintained for 24 hours and controlled gradual rewarming was then initiated. He regained consciousness 36 hours postrewarming with limited speech ability. The patient recovered with no further cardiac events and was discharged 3 weeks after admission, with no other serious complications. The patient was neurologically intact (cerebral performance category 1) at 6 months of follow-up. This case demonstrates the potential benefit and applicability of postarrest TTM in patients after repair of blunt myocardial rupture.

Penetrating cardiac trauma and the use of emergent extracorporeal membrane oxygenation and therapeutic hypothermia: When cooler heads prevail

This is a case of penetrating chest trauma with traumatic arrest from cardiac tamponade, right and left ventriculotomies, mitral valve injury and ventricular septal defect. Patient underwent resuscitative thoracotomy converted to clamshell thoracotomy for haemorrhage control. Ventriculotomies were repaired on initial damage control operation. Extracorporeal membrane oxygenation cannulation and therapeutic cooling bridged to definitive cardiac repair several days later. Patient was discharged to an inpatient rehabilitation facility in 16 days.

Cardiac Arrest Disrupts Caspase-1 and Patterns of Inflammatory Mediators Differently in Skin and Muscle Following Localized Tissue Injury in Rats: Insights from Data-Driven Modeling

BACKGROUND

Trauma often cooccurs with cardiac arrest and hemorrhagic shock. Skin and muscle injuries often lead to significant inflammation in the affected tissue. The primary mechanism by which inflammation is initiated, sustained, and terminated is cytokine-mediated immune signaling, but this signaling can be altered by cardiac arrest. The complexity and context sensitivity of immune signaling in general has stymied a clear understanding of these signaling dynamics.

METHODOLOGY/PRINCIPAL FINDINGS

We hypothesized that advanced numerical and biological function analysis methods would help elucidate the inflammatory response to skin and muscle wounds in rats, both with and without concomitant shock. Based on the multiplexed analysis of inflammatory mediators, we discerned a differential interleukin (IL)-1α and IL-18 signature in skin vs. muscle, which was suggestive of inflammasome activation in the skin. Immunoblotting revealed caspase-1 activation in skin but not muscle. Notably, IL-1α and IL-18, along with caspase-1, were greatly elevated in the skin following cardiac arrest, consistent with differential inflammasome activation.

CONCLUSION/SIGNIFICANCE

Tissue-specific activation of caspase-1 and the NLRP3 inflammasome appear to be key factors in determining the type and severity of the inflammatory response to tissue injury, especially in the presence of severe shock, as suggested via data-driven modeling.

Induced hypothermia during resuscitation from hemorrhagic shock attenuates microvascular inflammation in the rat mesenteric microcirculation

Microvascular inflammation occurs during resuscitation following hemorrhagic shock, causing multiple organ dysfunction and mortality. Preclinical evidence suggests that hypothermia may have some benefit in selected patients by decreasing this inflammation, but this effect has not been extensively studied. Intravital microscopy was used to visualize mesenteric venules of anesthetized rats in real time to evaluate leukocyte adherence and mast cell degranulation. Animals were randomly allocated to normotensive or hypotensive groups and further subdivided into hypothermic and normothermic resuscitation (n = 6 per group). Animals in the shock groups underwent mean arterial blood pressure reduction to 40 to 45 mmHg for 1 h via blood withdrawal. During the first 2 h following resuscitation by infusion of shed blood plus double that volume of normal saline, rectal temperature of the hypothermic groups was maintained at 32°C to 34°C, whereas the normothermic groups were maintained between 36°C to 38°C. The hypothermic group was then rewarmed for the final 2 h of resuscitation. Leukocyte adherence was significantly lower after 2 h of hypothermic resuscitation compared with normothermic resuscitation: (2.8 ± 0.8 vs. 8.3 ± 1.3 adherent leukocytes, P = 0.004). Following rewarming, leukocyte adherence remained significantly different between hypothermic and normothermic shock groups: (4.7 ± 1.2 vs. 9.5 ± 1.6 adherent leukocytes, P = 0.038). Mast cell degranulation index (MDI) was significantly decreased in the hypothermic (1.02 ± 0.04 MDI) versus normothermic (1.22 ± 0.07 MDI) shock groups (P = 0.038) after the experiment. Induced hypothermia during resuscitation following hemorrhagic shock attenuates microvascular inflammation in rat mesentery. Furthermore, this decrease in inflammation is carried over after rewarming takes place.

Outcomes of asphyxial cardiac arrest patients who were treated with therapeutic hypothermia: a multicentre retrospective cohort study

INTRODUCTION

While therapeutic hypothermia (TH) is in clinical use, its efficacy in certain patient groups is unclear. This study was designed to describe the characteristics and outcomes of patients with out-of-hospital cardiac-arrest (OHCA) caused by asphyxia, who were treated with TH.

PATIENTS AND METHODS

A multicentre, retrospective, registry-based study was performed using data from the period 2007-2012. Comatose patients who were treated with TH after asphyxial cardiac arrest were included, while those who with cardiac arrest attributed to hanging, drowning or gas intoxication were excluded.

RESULTS

Of a total of 932 OHCA patients in the registry, 111 were enrolled in this study. The mean age was 65.8±16.3 years with individuals who were ≥65 years of age accounted for 61.3% of the cohort. Foreign-body airway obstruction was the most common cause (70.3%) of the cardiac arrest. Eighty patients (72.1%) presented with an initial non-shockable rhythm. In all institutions target TH temperatures were 32-34°C, but TH maintenance times varied. A total of 52 patients (46.8%) survived, of whom six patients (5.4%) showed a good neurologic outcome (cerebral performance category scale 1-2). The pupil light reflex, corneal reflex and time to return of spontaneous circulation (p=0.012, 0.015 and 0.032, respectively) were associated with survival. Witnessed arrest, age, previous lung disease, bystander basic life support and time factors were not associated with survival.

CONCLUSION

About half of patients who underwent TH after asphyxial cardiac arrest survived, but a very small number showed a good neurologic outcome. The TH maintenance times were not uniform in these patients. Additional research regarding both the appropriate TH guidelines for patients with asphyxial cardiac arrest and improvement of their neurologic outcome is needed.

Salvage techniques in traumatic cardiac arrest: thoracotomy, extracorporeal life support, and therapeutic hypothermia

PURPOSE OF REVIEW

Survival from traumatic cardiac arrest is associated with a very high mortality despite aggressive resuscitation including an Emergency Department thoracotomy (EDT). Novel salvage techniques are needed to improve these outcomes.

RECENT FINDINGS

More aggressive out-of-hospital interventions, such as chest decompression or thoracotomy by emergency physicians or anesthesiologists, seem feasible and show some promise for improving outcomes. For trauma patients who suffer severe respiratory failure or refractory cardiac arrest, there seems to be an increasing role for the use of extracorporeal life support (ECLS), utilizing heparin-bonded systems to avoid systemic anticoagulation. The development of exposure hypothermia is associated with poor outcomes in trauma patients, but preclinical studies have consistently demonstrated that mild, therapeutic hypothermia (34 °C) improves survival from severe hemorrhagic shock. Sufficient data exist to justify a clinical trial. For patients who suffer a cardiac arrest refractory to EDT, induction of emergency preservation and resuscitation by rapid cooling to a tympanic membrane temperature of 10 °C may preserve vital organs long enough to allow surgical hemostasis, followed by resuscitation with cardiopulmonary bypass.

SUMMARY

Salvage techniques, such as earlier thoracotomy, ECLS, and hypothermia, may allow survival from otherwise lethal injuries.

Clinical and translational aspects of hypothermia in major trauma patients: from pathophysiology to prevention, prognosis and potential preservation

The human body strives at maintaining homeostasis within fairly tight regulated mechanisms that control vital regulators such as core body temperature, mechanisms of metabolism and endocrine function. While a wide range of medical conditions can influence thermoregulation the most common source of temperature loss in trauma patients includes: exposure (environmental, as well as cavitary), the administration of i.v. fluids, and anaesthesia/loss of shivering mechanisms, and blood loss per se. Loss of temperature can be classified either according to the aetiology (i.e. accidental/spontaneous versus trauma/haemorrhage-induced temperature loss), or according to an unintended, accidental induction in contrast to a medically intended therapeutic hypothermia. Hypothermia occurs infrequently (prevalence<10% of all injured), but more often (30-50%) in the severely injured. Hypothermia usually come together with and may aggravate acidosis and coagulopathy (the "lethal triad of trauma"), which again may be associated with a high mortality. However, recent studies disagree in the independent predictive role of hypothermia and mortality. Prevention of hypothermia is imperative through all phases of trauma care and must be an interest among all team members. Hypothermia in the trauma setting has attracted focus in the past from a pathophysiological, preventive and prognostic perspective; yet recent focus has shifted towards the potential for using hypothermia for pre-emptive and cellular protective purposes. This paper gives a brief update on some of the clinically relevant aspects of hypothermia in the injured patient.

Main complications of mild induced hypothermia after cardiac arrest: a review article

The aim of the present study is to assess the complications of mild induced hypothermia (MIH) in patients with cardiac arrest. Presently, based on the guidelines of the American heart Association, MIH following successful cardiopulmonary resuscitation (CPR) in unconscious adult patients due to ventricular fibrillation (VF) with out-of-hospital cardiac arrest (OOHCA) is essential and required. However, MIH could be associated with complications in Patients with cardiac arrest. Studies conducted on the precautions and care following cardiac arrest and MIH were included. Valid scientific data bases were used for data collection. The obtained results from different studies revealed that mild MIH could be associated with numerous complications and the knowledge and awareness of the medical staff from the complications is required to guarantee successful therapeutic approaches in MIH following cardiac arrest which is a novel medical facility with different styles and complications. Overall, further future studies are required to improve the quality of MIH, to increase survival and to decrease complications rates.

Commotio cordis, therapeutic hypothermia, and evacuation from a United States military base in Iraq

BACKGROUND

Therapeutic hypothermia (TH) has been demonstrated to improve clinical outcomes after out-of-hospital ventricular fibrillation (VF) cardiac arrest. It remains unclear if TH can be safely and effectively used in the setting of traumatic arrest. Furthermore, the use of TH methods in the pre-hospital and transport environments remain poorly established and a domain of active investigation.

OBJECTIVES

To describe a case of successful TH utilization after blunt trauma with commotio cordis and pulmonary contusion, and to describe the continuation of TH during international fixed-wing aeromedical transport.

CASE REPORT

A 33-year-old active duty soldier suffered blunt chest trauma and immediate VF arrest. He was successfully resuscitated with cardiopulmonary resuscitation and defibrillation attempts. Given his ensuing comatose post-arrest state, he was therapeutically cooled and subsequently evacuated from Iraq to Germany, with cooling maintenance established in flight without the availability of training or commercial cooling equipment. The patient exhibited an eventual excellent neurologic recovery. To utilize TH for this patient, military physicians with limited local resources employed a telemedical approach to obtain a hypothermia protocol to develop a successful treatment plan.

CONCLUSIONS

The patient's successful resuscitation suggests that care should not be withheld for blunt trauma patients without vital signs in the field if VF is present, until the differential diagnosis of commotio cordis has been considered.