β-Blocker Ingestion: An Evidence-Based Consensus Guideline for Out-of-Hospital Management

In 2003, US poison centers were contacted regarding ingestion of β-blockers by 15,350 patients including 3766 (25%) under 6 years of age; 7415 (48%) were evaluated in healthcare facilities and 33 died. An evidence-based expert consensus process was used to create this guideline. Relevant articles were abstracted by a trained physician researcher. The first draft of the guideline was created by the primary author. The entire panel discussed and refined the guideline before its distribution to secondary reviewers for comment. The panel then made changes in response to comments received. The objective of this guideline is to assist US poison center personnel in the appropriate out-of-hospital triage and management of patients with suspected ingestions of β-blockers by describing the process by which a β-blocker ingestion might be managed, identifying the key decision elements in managing cases of β-blocker ingestion, providing clear and practical recommendations that reflect the current state of knowledge, and identifying needs for research. This guideline applies to ingestion of β-blockers alone and is based on an assessment of current scientific and clinical information. The panel recognizes that specific patient care decisions may be at variance with this guideline and are the prerogative of the patient and health professionals providing care, considering all of the circumstances involved. Recommendations are in chronological order of likely clinical use; the grade of recommendation is in parentheses. 1) Patients with stated or suspected self-harm or who are the victims of a potentially malicious administration of β-blocker should be referred to an emergency department immediately. In general, this should occur regardless of the dose reported (Grade D). 2) Patients without evidence of self-harm should have further evaluation, including determination of the precise dose ingested, history of other medical conditions, and the presence of co-ingestants. Ingestion of either an amount that exceeds the usual maximum single therapeutic dose or an amount equal to or greater than the lowest reported toxic dose (whichever is lower) warrants consideration of referral to an emergency department. Ingestion of any excess dose of any β-blocker in combination with a calcium channel blocker or the ingestion of any excess dose by an individual with serious underlying cardiovascular disease also warrants referral to an emergency department (Grade C). 3) Do not induce emesis. Consider the oral administration of activated charcoal if it is available and no contraindications are present but do not delay transportation to administer charcoal (Grade A). 4) Asymptomatic patients who ingest more than the referral dose should be sent to an emergency department if the ingestion occurred within 6 hours of contacting the poison center for an immediate-release product other than sotalol, within 8 hours of contacting the poison center for a sustained-release product, and 12 hours if they took sotalol (Grade C). 5) Ambulance transportation is recommended for patients who are referred to emergency departments because of the potential for life-threatening complications of β-blocker overdose. Provide usual supportive care en route to the hospital, including intravenous fluids for hypotension (Grade D). 6) Follow-up calls should be made to determine outcome at appropriate intervals for up to 12–24 hours based on the judgment of the poison center staff (Grade D). 7) Asymptomatic patients who are referred to healthcare facilities should be monitored for at least 6 hours after ingestion if they took an immediate-release preparation other than sotalol, 8 hours if they took a sustained-release preparation, and 12 hours if they took sotalol. Routine 24-hour admission of an asymptomatic patient who has unintentionally ingested a sustained-release preparation is not warranted (Grade D).