Supraglottic devices: a possible role in prehospital toxic mass casualty event?

Rapidly progressive respiratory failure is the leading cause of death from inhalation of toxic chemical warfare agents. In an expected chaotic scenario, direct laryngoscopic tracheal intubation is unlikely to be easily and quickly performed due to shortage of medical personnel experienced with laryngoscopy and/or reduced dexterity imposed by the protective gear worn by the caregivers. Supraglottic devices have increasingly been used for emergent airway control in prehospital settings, thus avoiding the need for laryngoscopy.

Laryngeal mask airway insertion by anesthetists and nonanesthetists wearing unconventional protective gear: a prospective, randomized, crossover study in humans.

Background: Mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The laryngeal mask airway is part of the difficult airway algorithm. The authors evaluated the success rate and the time to secure airways by mask by anesthetists, surgeons, and novices when wearing either surgical attire or full antichemical protective gear that included butyl rubber gloves and a filtering antigas mask.

Antichemical protective gear prolongs time to successful airway management: a randomized, crossover study in humans.

Background: Airway management is the first step in resuscitation. The extraordinary conditions in mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The authors evaluated whether wearing surgical attire or antichemical protective gear made any difference in anesthetists' success of airway control with either an endotracheal tube or a laryngeal mask airway.

'Ecstasy' intoxication: life-threatening manifestations and resuscitative measures in the intensive care setting.

Objective: The ingestion of 3,4-methylenedioxymethamphetamine ('ecstasy') can cause severe neurological impairment and multi-system damage. We describe the potentially life-threatening clinical features and the management of intoxication by this psychedelic drug in patients transferred from emergency services to the intensive care area.

Methods: We conducted a retrospective analysis of 'ecstasy'-intoxicated patients admitted to a municipal hospital during a three-month period.

Flumazenil attenuates development of tolerance to diazepam after chronic treatment of mice with either isoflurane or diazepam.

Unlabelled: In an effort to clarify the mechanism of action of isoflurane, we studied the effect of flumazenil on mice chronically treated with isoflurane or diazepam. Mice were pretreated with diazepam, isoflurane, or saline, with and without flumazenil. After 2 wk, responses to isoflurane and diazepam were assessed, and central benzodiazepine receptor (CBR) binding characteristics were assayed.

Electromechanical impairment of human auricle and rat myocardial strip subjected to exogenous oxidative stress.

Objective: Animal myocardial dysfunction induced by remote ischemia-reperfusion (IR) was shown to be partly accomplished via a direct effect of the pro-oxidant xanthine oxidase (XO). This direct remote effect was not tested in humans. We now assessed the performance of human auricles in the presence of solutions containing XO and/or allopurinol and compared them to those of rat myocardial strips.

Halothane, isoflurane, and fentanyl increase the minimally effective defibrillation threshold of an implantable cardioverter defibrillator: first report in humans.

Unlabelled: Placing an implantable cardioverter defibrillator (ICD) involves the induction of ventricular fibrillation, whereupon the minimally effective defibrillation energy threshold (DFT) is determined. We evaluated the effects of 0.7% halothane, 1% isoflurane, or 1.

Dextromethorphan for the reduction of immediate and late postoperative pain and morphine consumption in orthopedic oncology patients: a randomized, placebo-controlled, double-blind study.

Background: Postoperative pain is mediated centrally by N-methyl-D-aspartate (NMDA) receptors. The beneficial effects of preincision oral dextromethorphan (DM), which is an NMDA antagonist, on postoperative pain and intravenous patient-controlled analgesia (IV-PCA) morphine (MO) consumption have been examined in patients undergoing surgery. The authors investigated 75 patients who underwent surgery for bone and soft tissue malignancies, in whom postoperative pain is more severe compared with patients who undergo general surgery.

Perioperative care of children with nerve agent intoxication.

Nerve agents (NA) present a major threat to civilian populations. When a ballistic system is used for spreading poison, multiple trauma, as well as toxic trauma could be caused. Children are more susceptible, due to their smaller physiological reserve.

External pacing does not potentiate allopurinol protection of the heart from liver ischemia-reperfusion -- a study in an isolated perfused liver-heart rat model.

Background: We recently demonstrated that isolated paced hearts perfused with modified Krebs-Henseleit solution containing high dose allopurinol (1 mM) were protected from liver ischemia-reperfusion (IR)-induced reperfusion injury. The objective was to study the effects of low dose allopurinol together with external pacing in attenuating myocardial reperfusion dysfunction following liver IR in the same double organ model.

Material And Methods: Isolated rat livers were perfused with modified Krebs-Henseleit solution (groups 1 and 2, n=8/all groups) or underwent global ischemia (groups 3-6) for 120 minutes.

Liver glutathione level influences myocardial reperfusion injury following liver ischemia-reperfusion.

Background: N-acetyl-L-cysteine (NAC) both replenishes reduced glutathione (GSH) and mitigates reperfusion injury. We hypothesized that liver content of GSH could affect remote myocardial reperfusion injury following liver ischemia-reperfusion.

Material And Methods: Following stabilization (30 min), isolated rat livers (6/group) were perfused with Krebs-Henseleit solution (two control groups) or made globally ischemic (two ischemia groups) for 120 min.

Selective attenuation of acute lung ventilatory injury by methylene blue after liver ischemia-reperfusion: a drug response study in an isolated perfused double organ model.

Background: Liver transplantation-related ischemia-reperfusion (IR) is associated with the generation of stress oxidants that can spread damage remotely. Methylene blue (MB) had been shown to reduce lung neutrophils sequestration after in vivo intestinal IR and to have a dose-dependent potential for abrogating oxidant-induced ex vivo aortal ring reperfusion injury after liver IR. We now investigated MB's dose-dependent capabilities in preventing acute lung injury after the same liver IR.

Bcl-2 overexpression protects photooxidative stress-induced apoptosis of photoreceptor cells via NF-kappaB preservation.

We recently showed that photooxidative stress on cultured photoreceptor cells results in down-modulation of NF-kappaB activity which then leads to apoptosis of cultured 661W photoreceptor cells. In an effort to further delineate the mechanism of photoreceptor cell death, we sought to determine the effects of Bcl-2 overexpression on cell survivability. Wild-type 661W cells were transfected with the plasmid construct pSFFV-neo-Bcl-2 and several clones were isolated.

Methylene blue abolishes aortal tone impairment induced by liver ischemia-reperfusion in a dose response manner: an isolated-perfused double-organ rat model study.

Liver ischemia-reperfusion (IR) generates remote organ reperfusion injury attributable to oxidative mediators. We tested the protective properties of methylene blue (MB) on aortal dysfunction. An ex vivo rat liver-aortal ring model was used to study the results of aortal exposure to post-ischemia (IR) hepatic effluent and its response to phenylephrine and isosorbide dinitrate in the absence or presence of increasing concentrations of MB in the effluent.

Dextromethorphan attenuation of postoperative pain and primary and secondary thermal hyperalgesia.

Purpose: To determine the effect of 90 mg dextromethorphan (DM) p.o. vs placebo 90 min preoperatively, on the immediate and delayed postoperative course.

Lung preconditioning with N-acetyl-L-cysteine prevents reperfusion injury after liver no flow-reflow: a dose-response study.

Background: Circulating xanthine oxidase activity and the generated oxidants have been linked to lung reperfusion injury from no flow-reflow conditions in other organs after organ transplantation or surgery. N-acetyl-1-cysteine (NAC), an oxidant scavenger, promotes glutathione in its reduced form (GSH) that is depleted during ischemia. We have recently demonstrated its efficacy in protecting lungs from reperfusion injury if administered during reperfusion of postischemic liver.

N-acetyl-L-cysteine for preventing lung reperfusion injury after liver ischemia-reperfusion: a possible dual protective mechanism in a dose-response study.

Background: Acute lung reperfusion injury (ALI) frequently follows an ischemic event in another organ, such as organ transplantation. We recently demonstrated that lung priming with N-acetyl-L-cysteine (NAC) prevented liver ischemia-reperfusion (IR)-induced ALI pending on reduced glutathione (GSH) amount of replenishment. We now assessed the therapeutic effect of NAC-in preventing ALI caused by liver IR-if administered to the lung during liver reperfusion.

Flumazenil potentiation of postoperative morphine analgesia.

Objective: The goal of this study was to test the effect of concomitant administration of flumazenil (FL) and morphine (MO) on immediate postoperative analgesia and the MO requirement to control pain in human beings.

Design And Interventions: Thirty-six patients undergoing inguinal hernioplasty under lidocaine epidural anesthesia were enrolled in this double-blind, randomized, controlled study. On the first complaint of pain, either MO (2 mg) only or MO (2 mg) plus FL (0.

Anaesthesia and critical care considerations in nerve agent warfare trauma casualties.

Nerve agents (NA) (tabun, sarin, suman, VX) have been stocked around the world for some time and still present a major threat to civilian as well as to military populations. Since NA can be delivered through both an aerial spray system and a ballistic system, victims could suffer both NA intoxication and multiple trauma necessitating urgent surgical intervention followed by intensive care. These patients can be expected to be extremely precarious neurologically, respiratorily and haemodynamically.

[FK506 (tacrolimus) does not increase hepatic damage due to hypoperfusion].

Deterioration of hepatic function following liver transplantation is a known complication, sometimes attributed to the use of cyclosporin A. Reaction to tacrolimus (Prograf), a relatively new and effective immunosuppressant drug, is thought to result in a much lower grade of organ dysfunction, especially in the transplanted liver. Using the ex-vivo rat model of isolated perfused liver, we evaluated hepatocellular damage and oxygen extraction when tacrolimus was administered following liver hypoperfusion.

Impairment of aortal tone by no flow-reflow conditions and its partial amelioration by mannitol.

Background: Although postischemic cardiac or pulmonary dysfunction can relate to the impact of remotely generated oxygen stress mediators on the heart, their direct effect on the vascular bed remains unresolved. Thus, we tested these remote effects in an ex-vivo double organ model.

Methods: After stabilization With Krebs-Henseleit solution, isolated rat livers were either perfused or made ischemic for 2 hours.

The role of dextromethorphan in pain control.

Purpose: To review the clinical benefits of dextromethorphan (DM) in pain management, describe its neuropharmacological properties.

Source: A Medline search was made for experimental and clinical data on DM use from 1967 to date using keywords nociception, acute and chronic pain control, N-methyl-D-aspartate, antagonists, dextromethorphan.

Principle Findings: The 930 DM citations mostly described its antitussive, metabolic and toxicological aspects, animal studies and its possible role in minimizing post-brain ischemia complications in humans.

Cumulative damaging effect of liver hypoperfusion and cyclosporine a on the peribiliary capillary plexus: a study in an isolated dually perfused rat model.

Background: Cyclosporine (CsA) is an essential posttransplantation immunosuppressive drug. It may cause hepatotoxicity, mostly cholestasis, by unknown mechanism. CsA causes nephrotoxicity mainly by increased vascular resistance.