Protocol deviations in intravenous acetylcysteine therapy for acetaminophen toxicity

Management of Acetaminophen Poisoning in the US and Canada: A Consensus Statement

Importance

The US and Canada currently have no formal published nationwide guidelines for specialists in poison information or emergency departments for the management of acetaminophen poisoning, resulting in significant variability in management.

Objective

To develop consensus guidelines for the management of acetaminophen poisoning in the US and Canada.

Evidence Review

Four clinical toxicology societies (America's Poison Centers, American Academy of Clinical Toxicology, American College of Medical Toxicology, and Canadian Association of Poison Control Centers) selected participants (n = 21). Led by a nonvoting chairperson using a modified Delphi method, the panel created a decision framework and determined the appropriate clinical management of a patient with acetaminophen poisoning. Unique to this effort was the collection of guidelines from most poison centers in addition to systematic collection and review of the medical literature. Comments from review by external organizations were incorporated before the guideline was finalized. The project began in March 2021 and ended in March 2023.

Findings

The search retrieved 84 guidelines and 278 publications. The panel developed guidelines for emergency department management of single or repeated ingestion of acetaminophen. In addition, the panel addressed extended-release formulation, high-risk ingestion, coingestion of anticholinergics or opioids, age younger than 6 years, pregnancy, weight greater than 100 kg, and intravenous acetaminophen use. Differences from current US practice include defining acute ingestion as an ingestion presentation from 4 to 24 hours after overdose was initiated. A revised form of the Rumack-Matthew nomogram was developed. The term massive ingestion was replaced with the term high-risk ingestion and denoted by a specific nomogram line. Other recommendations include specific criteria for emergency department triage, laboratory evaluation and monitoring parameters, defining the role of gastrointestinal decontamination, detailed management of acetylcysteine treatment, associated adverse effects, and stopping criteria for acetylcysteine treatment, as well as criteria for consultation with a clinical toxicologist. Finally, specific treatment considerations, including acetylcysteine dosing, fomepizole administration, and considerations for extracorporeal elimination and transplant evaluation, were addressed.

Conclusions and Relevance

This qualitative study provides a consensus statement on consistent evidence-based recommendations for medical, pharmacy, and nursing education and practice to optimize care of patients with acetaminophen poisoning.

Effect of a pharmacist-based toxicology consult service on appropriate use of intravenous N-acetylcysteine for acetaminophen toxicity: A retrospective cohort study

Background

Incorporating clinical pharmacists on the medical team has been associated with fewer medication errors and increased error interception. Due to the logistical complexities of the intravenous (IV) N-acetylcysteine (NAC) regimen for acetaminophen toxicity, many opportunities for medication errors exist. A pharmacist-based toxicology consultation service was implemented at our institution, allowing pharmacists to formally aid in the management of toxicology patients throughout their hospital admission, including those with acetaminophen toxicity. The purpose of this study was to evaluate the effect of a house-wide pharmacist-based toxicology consult service on errors associated with IV NAC treatment for patients admitted with acetaminophen toxicity.

Methods

A retrospective, pre-post cohort study was conducted on patients who received IV NAC for acetaminophen toxicity. The intervention evaluated was the implementation of a pharmacist-based toxicology consult service, known as the pharmacy toxicology team. The primary end point was the incidence of an error associated with IV NAC. An error was defined as the composite of inappropriate dose, administration rate, initiation, continuation, or discontinuation.

Results

Eighty-four patients were included; 30 patients in the pregroup, and 54 patients in the postgroup. Fewer patients experienced an error in the postgroup compared to the pregroup (30% vs 63%, P = 0.003).

Conclusion

The implementation of this unique pharmacist-based toxicology consult service was associated with fewer patients experiencing an error related to IV NAC therapy for acetaminophen toxicity. Application of this data may aid in the justification for development of clinical pharmacist-based toxicology consult services at other institutions.

A two-bag acetylcysteine regimen is associated with shorter delays and interruptions in the treatment of paracetamol overdose

BACKGROUND

The three-bag intravenous (IV) acetylcysteine regimen for paracetamol overdose is associated with frequent and long delays during treatment. This has not been previously studied in regard to the two-bag regimen.

AIMS

Our primary aim was to compare the cumulative duration of delays during IV acetylcysteine infusion between the three-bag and two-bag regimens. Secondary aims were to compare the frequency of delays and to identify causes for delay.

METHODS

This was a retrospective cohort study of patients receiving IV acetylcysteine for the treatment of paracetamol overdose, conducted at three Australian emergency departments. A cohort of patients treated with the three-bag regimen from October 2009 to October 2013 was compared to patients treated with the two-bag regimen from February 2014 to May 2020. Start times of each infusion were sourced from medical records and delays were calculated by comparing actual infusion time against prescribed time. Evidence of adverse drug reactions - gastrointestinal reactions and cutaneous and systemic non-allergic anaphylactoid reactions (NAARs) - were also recorded.

RESULTS

The three-bag cohort included 271 cases and the two-bag cohort included 598 cases. Delays were significantly shorter in the two-bag cohort, compared to the three-bag cohort: median delay 35 min (IQR: 15, 70) vs 65 min (IQR: 40, 105), p < 0.01. Delays longer than 1 h were less frequent in the two-bag cohort: 31% vs 51%, p < 0.01. NAARs were associated with significantly longer delays in both cohorts and were more frequent in the three-bag cohort.

CONCLUSIONS

The two-bag regimen was associated with significantly fewer and shorter delays. NAARs, which were more frequent in the three-bag cohort, were associated with significantly longer delays.