naloxone and Shock--Traumatic

Endogenous opioid peptides are released in response to stressful situations, such as circulatory shock, both as hormones and as central and peripheral neurotransmitters. Naloxone, an opiate antagonist, improves cardiovascular function in a variety of animal models of shock caused by endotoxemia, hemorrhage, anaphylaxis, or spinal trauma. Administration of thyrotropin-releasing hormone (TRH) in supraphysiologic doses also has pressor effects in these shock models. Given acutely after injury, TRH improves recovery in models of spinal trauma; however, the experimental effects of TRH do not involve action at the opiate receptor. Clinical evaluation of the use of naloxone in patients with shock has been largely limited to treatment of sepsis. The paucity of prospective, randomized trials makes these clinical data difficult to evaluate, but in septic patients the use of naloxone does not seem to improve survival. The use of naloxone in shock of other etiologies has not been clinically investigated, and may hold greater promise. Acute-phase treatment of spinal trauma victims with TRH is currently undergoing clinical trials.

Topics: Adult; Animals; Blood Pressure; Endorphins; Humans; Hypotension; Ischemia; Naloxone; Shock, Hemorrhagic; Shock, Septic; Shock, Traumatic; Thyrotropin-Releasing Hormone

Topics: Animals; Disease Models, Animal; Evoked Potentials; Indomethacin; Naloxone; Neural Conduction; Nimodipine; Rats; Serotonin Antagonists; Shock, Traumatic; Spinal Cord Injuries

In acute experiment on 86 adult rabbits with traumatic shock modelled according to Cannon, it was established that intravenous administration of Nalorphine at the doses of 0.5 and 2 mg/kg of weight at the early period of shock contributed to prolongation of lifetime of the majority of animals. In some of them, the small doses accelerated the occurrence of lethal outcome. In administration of 0.1 mg/kg of weight of Naloxone, almost all the animals survived. At the late period of shock, the effectiveness of these preparations is insufficient.

Topics: Animals; Nalorphine; Naloxone; Rabbits; Shock, Traumatic

Twelve patients with traumatic shock caused by a mechanical trauma were treated with narcanti within 6 h after trauma with a single dose 0.4 mg, and then intravenously in drops (0.4 mg/100 ml of the sodium chloride solution) with the general dose 2.8 +/- 0.8 mg. It gave favourable hemodynamic and respiratory effects and contributed to stabilization of the indices of metabolism homeostasis.

Topics: Hemodynamics; Homeostasis; Humans; Infusions, Intravenous; Injections, Intravenous; Naloxone; Respiration; Shock, Traumatic; Sodium Chloride; Solutions; Wounds and Injuries

In their acute experiments on 86 rabbits the authors have established that the intravenous administration of nalorphine and naloxone produces a marked therapeutic effect only during the early period of experimental traumatic shock. In most of the animals there was a reliable extension of the lifetime (nalorphine) and an increase in the survival rate (naloxone). In a lesser part of the animals the administration of nalorphine had no considerable influence on the outcomes. During the late period the therapeutic effect of these drugs has not yet been manifested. A conclusion has been made that the contradictory data in the literature concerning the effect of nalorphine and naloxone on the course of experimental traumatic shock seem to depend on the fact that they were administered at various stages of this pathologic process. It is pointed out that it is advisable to administer these drugs (especially naloxone) at the pre-hospital stage in the patients with traumatic shock.

Topics: Animals; Blood Pressure; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Nalorphine; Naloxone; Rabbits; Shock, Traumatic; Time Factors

Topics: Animals; Brain; Catecholamines; Hemodynamics; Male; Naloxone; Rats; Rats, Inbred Strains; Serotonin; Shock, Traumatic

Experiments on rabbits were made to examine the effect of naloxone, a specific antagonist of opiates and endogenous opioid peptides, on traumatic shock. Naloxone (0.1-1.0 mg/kg) injected intravenously 2-15 minutes after trauma produced no effect on the arterial pressure and the heart rate. As compared with control animals, the lifespan of animals with trauma decreased. It is suggested that endogenous opioid peptides may play a protective and adaptive role in the torpid phase of traumatic shock.

Topics: Animals; Blood Pressure; Heart Rate; Male; Naloxone; Rabbits; Respiration; Shock, Traumatic