In acute severe anticholinesterase poisoning by organophosphate compounds, pralidoxime (P-2-AM, pyridine-2-aldoxime methiodide) used in the recommended doses, intravenously, has not been shown to reactivate the inhibited cholinesterase, as evidenced both clinically and biochemically. In vitro studies using pralidoxime iodide up to ten times the recommended concentrations, produced insignificant reactivation of cholinesterases inhibited by the organophosphate insecticide Bidrin (di-methyl-3-hydroxyl-N, N-dimethyl-crotonamide phosphate). This was even so despite prolonged exposure of the inhibited cholinesterases to the oxime. The value of pralidoxime as a reactivator of phosphorylated cholinesterases is therefore in doubt, and should not be used in preference to large doses of atropine and other supportive treatment in poisoning by organophosphate insecticides.
Matched MeSH terms: Pralidoxime Compounds/pharmacology*; Pralidoxime Compounds/therapeutic use
With the establishment of the inadequate efficiency of atropines and oximes in reducing morbidity and mortality of patients poisoned by organophosphates, more attention is given to using other methods such as Fresh Frozen Plasma (FFP) as a bioscavenger to mop up organophosphate toxins. This randomized clinical trial was conducted on 56 organophosphate poisoned patients who were randomly assigned to the FFP and control groups in order of admission. The routine treatment in both groups included atropine and, in moderate to severe cases of poisoning, pralidoxime. The FFP group received four packs of FFP as stat dose at the beginning of treatment. No significant difference was seen between the two groups on the atropine and pralidoxime dosage, hospitalization length and mortality. The present study showed that using four packs of FFP as stat dose at the onset of treatment had no significant effect on the clinical course of organophosphate poisoned patients.
Matched MeSH terms: Pralidoxime Compounds/therapeutic use
Poisoning is one of the most important causes of morbidity and mortality in developing countries like India. Anticholinesterase compounds like organophosphates (OP) and carbamates account for the majority of these poisoning cases because of their easy availability and agricultural use. Carbamates are as popular as OPs as insecticides that often go undiagnosed. A fatal case of carbofuran poisoning is presented where serial cholinesterase estimation played a major role in the diagnosis of the same. The pertinent medical literature on carbofuran poisoning is reviewed. The establishment of poison information center in each state is needed for proper diagnosis and management of poisoning cases.
Matched MeSH terms: Pralidoxime Compounds/therapeutic use
Organophosphorous poisoning causing isolated laryngeal paralysis has only been rarely reported before. We describe a case of difficult extubation in a patient with organophosphorous poisoning, the cause of which was found to be bilateral vocal fold palsy. This is a type of intermediate paralysis that recovers with time. Such a condition should be thought of as a cause of dyspnoea or difficult extubation in patients with organophosphorous poisoning.
Matched MeSH terms: Pralidoxime Compounds/therapeutic use
From 1970 to 1984, 100 patients suffering from organophosphate poisoning were treated in the Intensive Care Unit at the University Hospital. These patients developed signs and symptoms of cholinergic over-activity and were treated with continuous intravenous atropine. Many of the patients also developed acute respiratory failure, which necessitated ventilatory support in the form of intermittent positive pressure ventilation. Other measures included the use of inotropes and nutritional support. Daily estimation of serum cholinesterase levels were useful in assessing degree of recovery of the patients from the effects of the organophosphates.
Matched MeSH terms: Pralidoxime Compounds/therapeutic use
On the battlefields of Syria, many innocent civilians have been killed or injured by sarin poisoning. In Malaysia in February 2017, a North Korean man was assassinated with VX at Kuala Lumpur International Airport. In the face of such threats, a more effective antidote against organophosphonate acetylcholinesterase (AChE) inhibitors is needed, one that can freely penetrate into the central nervous system (CNS) through the blood-brain barrier (BBB). In the 1995 Tokyo subway sarin attack, which produced more than 6,000 victims, 2-pyridinealdoxime methiodide was the most commonly used antidote in hospitals, but it was unable to prevent CNS damage and no other oximes have been approved for use in Japan. Ultimately, 12 people died, and many victims had severe neurological injuries or sequelae. Although more than 25 years have passed since the incident, progress has been slow in the development of a new antidote that can penetrate the BBB, restore AChE activity in the CNS, and definitely prevent brain injury. From the perspectives of countering terrorism and protecting innocent people from nerve agent attacks, the search for nerve agent antidotes should be accelerated with the goals of improving both survival and quality of life. This review gives an overview of a series of our studies on the development of a new antidote since the Tokyo subway sarin attack and emphasizes that there is unfortunately still no promising antidote for saving the CNS in Japan.