A Pilot Study Using Rocuronium to Prevent Intermediate Syndrome After Organophosphorus Insecticide Poisoning
Pilot Study - Assessing the Impact of Using a Neuromuscular Blocking Agent to Reduce Neuromuscular Junction Damage and Intermediate Syndrome in Organophosphorus (OP) Insecticide Poisoned Patients Requiring Ventilation
Organophosphate pesticide poisoning causes close to 300 000 deaths per year worldwide. Many patients who ingest organophosphates require ventilation; of these patients approximately 50% die. Much of the mortality in these ventilated patients is secondary to intermediate syndrome. This is because OP pesticides inhibit acetylcholinesterase, causing an excess of acetylcholine at nerve synapses and the neuromuscular junction (NMJ). At the NMJ, the excess acetylcholine causes overstimulation and damage, which may lead to sudden respiratory arrest or prolonged ventilation and its associated complications.
The investigators believe that blocking these receptors using a neuromuscular blocking agent such as Rocuronium will protect the NMJ from damage and thus prevent intermediate syndrome and reduce number of intubated days and mortality.
In this pilot randomised controlled trial Rocuronium, a competitive nicotinic receptor antagonist, will be used to bind to the receptor at the neuromuscular junction and to block the effects of the accumulated acetylcholine. The effects of OP pesticide on cholinesterase in the blood will then be monitored and Rocuronium withdrawn using Sugammadex as the OP is eliminated from the body.
Primary outcome: Number of days intubated
Effect of Rocuronium will be reversed at the appropriate time using Sugammadex 16mg/kg as a single dose which may be repeated once.
IV Rocuronium to be given: Bolus dose of Rocuronium 0.3 mg/kg to achieve >95% inhibition as indicated by Train of Four monitoring Continuous infusion of 1.5 mg/kg/hr to maintain level of inhibition To continue until two rises in butyrylcholinesterase seen or for a maximum of 5 days
IV Rocuronium to be given: Bolus dose of Rocuronium 0.3 mg/kg to achieve 50% inhibition as indicated by Train of Four monitoring Continuous infusion of 1.5 mg/kg/hr to maintain level of inhibition To continue until two rises in butyrylcholinesterase seen or for a maximum of 5 days
No Rocuronium will be given
Inclusion criteria: Male or female Age over 16 Clinical diagnosis of OP insecticide poisoning Admission to Intensive Care Unit for Ventilation Informed consent from family Train of four measurement > 50% Exclusion criteria: Age 16 or under Pregnant Consent not obtained from patient or patient's family