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Three Part Question

[In overdose of tricyclic antidepressant] is [gastric lavage better than charcoal or nothing] at [reducing toxicity]?

Clinical Scenario

A 23 year old air hostess is brought into the department having been found collapsed next to an empty bottle of amitryptilene. She has a Glasgow Coma Scale score of 7/15, tachycardic and twitchy. After a rapid sequence induction and intubation you wonder whether there is any benefit from gastric lavage.

Search Strategy

Medline 1966-10/02 using the OVID interface.
[{exp gastric lavage OR gastric lavage.mp OR washout.mp OR exp irrigation or lavage.mp OR gastric emptying.mp} AND {exp disipramine OR exp antidepressive agents,tricyclic OR exp antidepressive agents OR exp amitriptyline OR exp imipramine OR tricyc$.mp OR amitriptyline.mp} AND {exp poisoning OR poisoning.mp OR exp overdose OR overdose.mp} LIMIT to human AND English Language]

Search Outcome

Altogether 82 papers found, 81 of which were not relevant to the question. The remaining paper is shown in the table.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Bosse GM et al, 1995, USA	51 patients presenting with tricyclic overdose. Charcoal only (n=22) v charcoal then lavage (n=14) v charcoal then lavage then charcoal (n=15) 39 intubated	RCT	Mean Length of Stay	93.3 (+/- 94.3) hours v 107.2 (+/- 106.8) hours v 66.7(+/- 41.7) hours (p=0.473)	Not blinded Small numbers Variations between presenting GCS and drug levels between groups
			Mean Length ICU stay	66.9 (+/- 96.0) hours v 54.1(+/- 34.3) hours v 34.4(+/-27.3) hours (p=0.436)
			Mean Mechanical Ventilation Time	43.4(+/- 17.7) hours v 24.1(+/-18.3) hours v 17.8 (+/- 14.0) hrs (p=0.321)
			Aspiration	2/22 v 3/14 v 3/15 (p=0.501)

Comment(s)

This study shows no statistically significant difference between the three groups. Although it seems small, it has 80% power for showing a change of ITU admission time of 12 hours at p=0.05. Furthermore, a study by Watson et al showed that only 8.7% (95% C.I. 0.4-21.7%) of the estimated dose of tricyclic was recovered by gastric lavage (2).

Editor Comment

For UK position statement on gastric lavage see http://www.spib.axl.co.uk/toxbaseindex.htm

Clinical Bottom Line

There is no evidence for gastric lavage in tricyclic antidepressant overdose.

References

1. Bosse GM, Barefoot JA, Pfeifer MP, et al. Comparison of three methods of gut decontamination in tricyclic antidepressant overdose. J Emerg Med 1995;13(2):203-9.
2. Watson WA, Leighton H, Guy J, et al. Recovery of cyclic depressants with gastric lavage. J Emerg Med 1989;7(4):373-7.