Decontamination : Who, why, when and how

Decontamination When should patient be decontaminated? risk of morbidity and/or mortality associated with ingestion What type of decontamination should be used? Depends on clinical circumstances and other treatment options

Decontamination w Syrup of Ipecac w Gastric lavage w Activated charcoal multi dose with cathartic w Whole bowel irrigation

Where is the Evidence ? Based on w Animal studies w Volunteer studies w clinical studies Difficulty due to w serious ingestions excluded w conflicting results

Where is the Evidence Position statements released in 1997 by AACT and EAPCCT “Overall the mortality from acute poisoning is less than 1 % and the challenge for clinicians is to identify promptly those who are at most risk of developing serious complications and who might potentially benefit, therefore, from gastrointestinal decontamination.”

Syrup of Ipecac w Plant extract previously abused by bullimics w needs to be given EARLY w induces vomiting by gastric and central mechanism Contraindicated in w unprotected airway w corrosive w very little evidence for or against w possible role in the home for children

Gastric lavage w No studies demonstate efficacy even < 60 min.s w Studies exclude serious poisonings Contraindicated: w dodgy airway reflexes w corrosives w hydrocarbon

Gastric lavage w May increase risk of aspiration w May lead to pharyngeal injury w alleged to increase absorption in some cases w Has lead to significant return of ingestants up to 12 hours post ingestion(salicylates) Indication w Serious life threatening poisoning with well protected airway (level IV evidence)

Activated charcoal w Will adsorb many toxins in GI tract BUT: Alcohols Li +, Fe 2+ (probably all alkali metals) w Ratio should be 10:1 AC:toxin w Evidence from volunteer studies that absorption will be  if < 60 min.s w Little to suggest benefits outcome clinically or absorption post 60 min.s DO NOT GIVE ROUTINELY

Activated charcoal w Beware the unprotected airway or aspiration risk w dose is 50g adult, 1g/kg in a child Cathartics w Alleged to increase bowel transit time of toxin w Evidence only from animal and volunteer studies w Unlikely to benefit

Multi dose activated charcoal w Works by GI dialysis drugs with significant enterohepatic circulation w examples: theophylline anticonvulsants salicylates digoxin

Multi dose activated charcoal w Good, though indirect evidence of effect in digoxin poisoning w 50g q 6 hrly OR by NG infusion if intubated w up to 1g/kg suggested for serious theophylline poisonings w Justifies “late” instigation of charcoal

Whole bowel irrigation Used for w SR/EC preparations w when charcoal is ineffective w No controlled clinical studies to back up use physically speeds up transit through GI tract single dose charcoal given prior to starting

Whole bowel irrigation w PEG ELS (“go-lytely”) is used  does not cause significant water/electrolyte disturbance w frequently causes vomiting, requires NGT w airway must be protected w ileus is CI but has been reversed with neostigmine w dose is mls/kg/hr w endpoint is clear rectal effluent, median time to achieve this is 6 hours

A 50 kg female presents having ingested 6 g of paracetamol 5 hours previously

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 70 kg male presents having ingested 14 g paracetamol 3 hours before

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 70 kg male presents having ingested 14 g paracetamol 1 hour before

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 45 kg female presents having ingested 2 g of a tricyclic antidepressant 1 hour before

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 50 kg male presents unconscious having ingested an unknown amount of a tricyclic antidepressant at an unknown time

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 67 kg male presents having ingested 800 mg of a tricyclic antidepressant 6 hours before. He is well.

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 80 kg male presents having ingested 100 mg of diazepam 4 hours before

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 65 kg female presents having ingested 3.5 g of Verapamil SR 4 hours before.

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None

A 45 kg female presents having ingested 2 g elemental iron 4 hours before. Tablets are noted on her plain AXR

Would You w Syrup of Ipecac w Gastric lavage w Gastric Lavage & AC w Gastric lavage & Whole bowel lavage w AC w Whole Bowel Lavage w None