heroin and Hypothermia

Xylazine has emerged in recent years as an adulterant in an increasing number of opioid-positive overdose deaths in the United States. Although its exact role in opioid-induced overdose deaths is largely unknown, xylazine is known to depress vital functions and cause hypotension, bradycardia, hypothermia, and respiratory depression.. In this study, we examined the brain-specific hypothermic and hypoxic effects of xylazine and its mixtures with fentanyl and heroin in freely moving rats.. In the temperature experiment, we found that intravenous xylazine at low, human-relevant doses (0.33, 1.0, 3.0 mg/kg) dose-dependently decreases locomotor activity and induces modest but prolonged brain and body hypothermia. In the electrochemical experiment, we found that xylazine at the same doses dose-dependently decreases nucleus accumbens oxygenation. In contrast to relatively weak and prolonged decreases induced by xylazine, intravenous fentanyl (20 μg/kg) and heroin (600 μg/kg) induce stronger biphasic brain oxygen responses, with the initial rapid and strong decrease, resulting from respiratory depression, followed by a slower, more prolonged increase reflecting a post-hypoxic compensatory phase, with fentanyl acting much quicker than heroin. The xylazine-fentanyl mixture eliminated the hyperoxic phase of oxygen response and prolonged brain hypoxia, suggesting xylazine-induced attenuation of the brain's compensatory mechanisms to counteract brain hypoxia. The xylazine-heroin mixture strongly potentiated the initial oxygen decrease, and the pattern lacked the hyperoxic portion of the biphasic oxygen response, suggesting more robust and prolonged brain hypoxia.. These findings suggest that xylazine exacerbates the life-threatening effects of opioids, proposing worsened brain hypoxia as the mechanism contributing to xylazine-positive opioid-overdose deaths.

Topics: Analgesics, Opioid; Animals; Drug Overdose; Fentanyl; Heroin; Humans; Hypothermia; Hypoxia; Hypoxia, Brain; Oxygen; Rats; Respiratory Insufficiency; Xylazine

We present the case of a 21-year-old female drug addict with severe accidental hypothermia (core body temperature 27.5 degrees C) and cardiorespiratory arrest. After successful cardiopulmonary resuscitation the patient was actively internally rewarmed without the use of extracorporal circulation. Although at the first clinical presentation the patient appeared to be dead, an excellent neurological outcome was achieved. This case report reviews the epidemiology, pathophysiology, prognostic markers and the therapeutic approaches of severe hypothermia.

Topics: Adult; Analgesics, Opioid; Cardiopulmonary Resuscitation; Drug Overdose; Female; Heart Arrest; Heroin; Heroin Dependence; Humans; Hypothermia; Prognosis; Rewarming

A 20-year old woman presented with prolonged refractory ventricular fibrillation and pulmonary oedema following hypothermia while she was under self-administered heroin in an attempt to commit suicide. She was successfully resuscitated with cardiopulmonary bypass for core rewarming and internal defibrillation.

Topics: Adult; Cardiopulmonary Bypass; Drug Overdose; Female; Heroin; Humans; Hypothermia; Pulmonary Edema; Suicide, Attempted; Ventricular Fibrillation

The combination of severe hypothermia and noncardiogenic pulmonary edema secondary to an opiate overdose is presented. This case emphasizes the importance of ventilatory support and rewarming techniques available in the emergency department setting.

Topics: Drug Overdose; Heroin; Humans; Hypothermia; Male; Pulmonary Edema; Substance-Related Disorders