3. DISCUSSION
OP is the common form of poisoning accounting for 0.9-1.0% of the
patient admissions to hospital EDs in Nepal.2,4 The
most prevalent symptoms of OP poisoning are SLUDGE (salivation,
lacrimation, urination, defecation, gastric cramps, and
emesis).9 Signs and symptoms of OP poisoning can be
divided into acute cholinergic crisis, intermediate syndrome (IMS) and
type 3 paralysis or organophosphate induced delayed polyneuropathy
(OPIDP).10 IMS is muscle paralysis involving mainly
bulbar, respiratory, and proximal muscles of limbs following the acute
cholinergic phase, occurring 3-4 days after exposure. It usually
resolves in 1–3 weeks but may require mechanical ventilation if
indicated.9 Respiratory failure is the most common
cause of death in IMS.8,11 OPIDP occurs about 2-4
weeks after exposure to large doses of OP insecticide. It is
characterised by distal muscle weakness causing ataxia, foot drop and
claw hand, and is due to inhibition of neuropathy target esterase. It
may take weeks to months to recover. Rare complications of OP poisoning
are cardiac arrhythmias, pancreatitis, and hepatic
dysfunction.12 There have been cases of delayed
myelopathy after insecticide CPS ingestion.10Diagnosis of OP poisoning is primarily based on the clinical history,
the clinical signs and symptoms, smell of insecticides or solvents
involved, and reduced levels of RBC or plasma AchE. The management of OP
poisoning requires prompt identification of toxins and rapid
administration of atropine to counteract the cholinergic crisis.
Although psychotic symptoms such as restlessness, excitement,
hallucinations, and delirium have been reported following atropine
administration, atropine is an antidote for OP
poisoning.3 Exposure with dermal contact needs
immediate decontamination to reduce systemic
absorption.13 Further management requires adequate
supportive care including IV fluids, airway management, seizure control
and 2-PAM to reactivate AchE.2 One of the studies
shows atropine seemed to be as effective as atropine plus 2-PAM in the
treatment of acute OP poisoning. 2-PAM if used should be given within 48
hrs of poisoning.8 Immediate decontamination, oxygen,
ventilatory support and benzodiazepines for seizure control if required,
IV atropine, IV 2-PAM and IV fluids are of utmost importance for saving
a patient’s life.4 Also while dealing with cases of
suspected poisoning, stomach wash, blood, stool, urine and if possible
empty bottles of poison should be collected for medicolegal
registry.14