Examkin

Question

Difficulty: MediumMonitoring and Treatment Evaluation

A 19-year-old college student is brought to the emergency department 90 minutes after intentionally swallowing 20 grams of acetaminophen. The patient is currently asymptomatic with normal vital signs. Arrange the following steps for the appropriate sequential monitoring and treatment evaluation of this patient in the correct chronological order.

  1. 1Measure the serum acetaminophen concentration at 4 hours post-ingestion.
  2. 2Plot the serum acetaminophen concentration on the Rumack-Matthew nomogram.
  3. 3Initiate an intravenous infusion of N-acetylcysteine.
  4. 4Perform serial assessments of hepatic aminotransferases and coagulation studies.
  5. 5Discontinue the antidote infusion once the serum acetaminophen level is undetectable and transaminases are clearly improving.

Answer

The correct sequence begins with waiting until 4 hours post-ingestion to check the initial acetaminophen level, plotting it on the nomogram, starting N-acetylcysteine therapy, performing serial laboratory monitoring, and finally discontinuing the antidote when clinical recovery criteria are met.
The correct sequence reflects the standard guideline protocol for acute acetaminophen overdose. Because gastrointestinal absorption can be delayed, levels drawn before 4 hours are uninterpretable for risk stratification. Once a valid level is drawn at 4 hours post-ingestion, the Rumack-Matthew nomogram dictates the need for N-acetylcysteine (NAC). If NAC is started, ongoing evaluation of hepatic function (AST, ALT, PT/INR) is required to monitor for liver injury. Finally, treatment is discontinued only when clinical and laboratory criteria (undetectable acetaminophen, improving transaminases) are explicitly satisfied.

Step-by-Step Solution

1
Wait until 4 hours post-ingestion to measure the serum acetaminophen concentration.
An accurate peak serum level is obtained.
Levels drawn before 4 hours do not reflect peak absorption and cannot be reliably used with the nomogram.
2
Plot the obtained concentration on the Rumack-Matthew nomogram.
The patient's risk for hepatotoxicity is stratified.
This determines if the level is above the treatment line, warranting antidote therapy.
3
Initiate an intravenous infusion of N-acetylcysteine (NAC).
Hepatic glutathione stores are replenished.
Given the massive 20-gram ingestion, the level will likely fall above the treatment line, necessitating NAC to prevent irreversible liver injury.
4
Perform serial assessments of hepatic aminotransferases and coagulation studies.
Hepatic function is closely monitored during the treatment phase.
This tracks the progression of any potential hepatotoxicity and evaluates treatment efficacy.
5
Discontinue the NAC infusion once specific recovery criteria are met.
Antidote therapy is safely terminated.
Therapy can only be stopped when the serum acetaminophen level is undetectable and transaminases are clearly declining, indicating complete recovery.

Key Concept

Sequential monitoring and treatment evaluation of acute acetaminophen toxicity using the Rumack-Matthew nomogram and specific clinical criteria for discontinuation.
Estimated Time:1m 30s
Rate this question

Topics

Monitoring and Treatment Evaluation

More questions from this topic