PRINCIPLES OF MANAGEMENT

·       Maintain vital signs

·       Eliminate remaining poison

·       Combat side effects and complications

ORGANOSPHOSPHORUS: PRIORITIES IN MANAGEMENT

 ·       General Management as of any poisoning.

·       If gag reflex present? If present give stomach wash. If absent, intubate and give stomachwash.

·       Activated charcoal 50 gms stat and repeat if required.

·       Start oxygen 6liters by mask.

·       Inj. Atropine 1 mg IV increments, until bronchial and oropharyngeal secretions have ceased:maintainance therapy of continuous infusion of 0.05 mg/kg/hr. or IV 1 mg p r n dosages justto maintain HR above 100/min. Taper over 24-48 hours slowly with subcutaneous 1 mg doses q 6 hourly.

·       Inj. Diazepam 10-20 mg IV only if the patient has seizures.

·       Pralidoxime use in early cases (controversy exists)

INVESTIGATIONS

ROUTINE BLOOD TESTS (Hb, TC/DC, Na, K, Creat)

PLASMA PSEUDOCHOLINESTERASE <2000 (Normal= 3000-8000 ug/mL) A B Gases (to

look for type IIRespiratory failure)

CHEST X-RAY to look for chemical aspiration pneumonitisECG to look for ventricular arrhythmias

COMPLICATIONS TO LOOK FOR AND MANAGE

Aspiration pneumonitis Ventricular arrhythmias

Intermediate syndrome (develops from day 1-4 after after ingestion-needs ventilator support ifrespiratory failure sets in)

Atropine psychosis (Rx with IM Haloperidol 2.5-5.0 mg; reduce atropine dose) Convulsions (Rx IV Diazepam)

CARBAMATES

 ·       Like Organo-Phosphorus compounds, similar but short-lived effects due to spontaneous dissociation of carbamate-enzyme complex. There is no intermediate syndrome and CNS isless affected.

·       Symptomatic cases require atropine; fairly quick recovery is a rule.

PYRETHROIDS

 ·       Coma, Convulsion, Pulmonary Edema in severe cases.

·       Only supportive therapy

AROMATIC AND HALOGENATED HYDROCARBONS (eg ENDOSULPHAN)

 ·       Gastric Lavage (after taking necessary precaution against aspiration and chemical pneumonitis)

·       Activated Charcoal

·       Signs and symptoms are milder, (pupillary constriction is however absent)

·       Treatment is mostly supportive, and involves mainly correction of dyselectrolnytemias,treating aspiration pneumonia)

·       Treat as OP Poisoininge.gAtropinization, if pupillary constriction is present and OP poisoining cannot be ruled out. If certain about the nature of the consumed compound,Atropine is relatively contraindicated as it can worsen sympathetic overactivity.

·       Seizures to be treated with Diazepam IV.

OLEANDER (WHITE, YELLOW) (CERBERA THEVATIA)

 CF:-Nausea, Vomiting, Abdominal Pain, Diarrhoea O/E :- Hypotension, Bradyarrythmia, Syncope

MANAGEMENT

·       ABCDE as for any other poisoining.

·       Monitoring serum potassium ( Hyperekalemia)

·       IV fluids and dopamine for hypotension

·       Atropine for bradyarrhythmia

·       ECG monitoring

·       Cardiac pacing for uncontrolled bradycardia

KEROSENE ( PARAFFIN OIL) POISONING

 Properties causing toxicity : Low surface tension, Low viscosity.

CF :- Pulmonary Toxicity within 1-8 hours of ingestion – due to the poison aspirated into respiratory tract.

It is possible to have symptoms without radiological features and vice versa. X- Ray abnormalities are maximum at 72 hours.

Management :- Avoid Emesis and Gastric lavage.

 In severe cases, ventilation- Oxygen and PEEP can be used.

 If amount of consumption is large, Gastric Lavage to be considered, within 1 hour, with cuffed ET- Tube intubation. Corticosteroids/ Antibiotics do not significantly alter the morbidity and mortality.

 METHYL-ALCOHOL POISONING

·       CF :- Coma after a latent period of 8-36h.

If dilated pupils not reacting to light is seen permanent blindness is likely to ensue. Features of hypokinensis, rigidity and extrapyramidal signs develop in cases of putaminal necrosis. Fundoscopyto look for optic neuritis.

·       Management :-

1.      Gastric lavage if presents within 1h, of ingestion.

2.      Reversal of metabolic acidosis, Bicarbonate infusion in large doses.

3.      Monitor for hypernatremia and fluid overload, both of which can be as a result of acidosis correction.

4.      Inhibition of methanol oxidation :- Administer 50 gm ethanol, (125 ml of gin/whisky/ vodka)PO as loading dose, followed by 10-12g/h IV infusion, or 12- 15g/h IV in known alcoholics or 17-22 g/h IV in patients on haemodialysis. Ethanol can be administered in the dialysate fluid (1-2d/l) if the patient is receiving peritoneal dialysis.

5.      Indications for haemodialysis :- Consumption of > 30 gm of methanol. Blood methanolconcentration> 500 mg/l

Severe metabolic acidosis, pulmonary edema.Fundoscopic changes of optic neuritis. CNS dysfunction (putaminal necrosis)

6.      Folinic acid 30 mg IV q6hrly. (To protect against ocular toxicity)