What is rumack Matthew Line?
The Rumack-Matthews nomogram summarizes the relationship between plasma acetaminophen concentration (in µg/mL or µmol/L), the time after drug ingestion, and the risk of hepatic toxicity. The thick diagonal line of possible hepatic toxicity represents a 25 percent likelihood of disease.
Why does the Rumack-Matthew nomogram start at 4 hours?
The primary reason for starting at this time point was to eliminate (or at least diminish) the possibility of ongoing or delayed absorption. 4 Unfortunately, proper use of the Rumack-Matthew nomogram necessitates extending a patient’s emergency department (ED) length of stay by 4 hours or more.
How do you calculate acetaminophen overdose?
In adults, the minimum toxic dose of acetaminophen as a single ingestion is 7.5 to 10 g; acute ingestion of >150 mg/kg or 12 g of acetaminophen in adults is considered a toxic dose and carries a high risk of liver damage.
How do you read rumack Matthew nomogram?
The upper line of the nomogram is the “probable” line, also known as the Rumack-Matthew line. About 60% of patients with values above this line develop hepatotoxicity. The lower line on the nomogram is the “possible” line, which was subsequently added later per request of the U.S. FDA.
What is NAC protocol?
N-acetylcysteine (NAC) is the mainstay of therapy for acetaminophen toxicity. NAC has Federal and Drug Administration (FDA) approval for the treatment of potentially hepatotoxic doses of acetaminophen (APAP), and it is almost 100% effective if given within 8 hours post-ingestion.
What are the limitations on the use of the rumack Matthew nomogram?
The nomogram cannot be used if the patient presents more than 24 hours after ingestion or has a history of multiple acetaminophen ingestions.
How do you read a nomogram?
A nomograph is defined as a graph, usually containing three parallel scales graduated for different variables so that when a straight line connects values of any two, the related value may be read directly from the third vertical line at the point intersected by the line.
When is rumack Matthew nomogram used?
The nomogram predicts potential toxicity beginning at 4 hours after ingestion up to 24 hours after ingestion. Acetaminophen concentraions measured earlier than 4 hours post-ingestion may not be reliable. Concentrations measured 4-18 hours post-ingestion are most reliable.
Are nomograms accurate?
Nomograms provide accurate individualized estimates of outcomes.
How are nomograms constructed?
The initial steps in nomogram development include definition of the patient population and outcome, identification of important covariates, specification of the statistical model, and validation of its performance (Table 1). The first step in nomogram construction is to identify the source population.
What does the Rumack Matthew nomogram show?
The Rumack–Matthew nomogram, also known as the acetaminophen nomogram, is an acetaminophen toxicity nomogram. It plots serum concentration of acetaminophen against the time since ingestion, in order to predict possible liver toxicity and allow a clinician to decide whether to proceed with N-Acetylcysteine (NAC) treatment.
What is the Rumack-Matthews nomogram for acetaminophen toxicity?
All Rights Reserved. The Rumack-Matthews nomogram summarizes the relationship between plasma acetaminophen concentration (in µg/mL or µmol/L), the time after drug ingestion, and the risk of hepatic toxicity. The thick diagonal line of possible hepatic toxicity represents a 25 percent likelihood of disease.
What is the original Rumack-Matthew line?
The original line, sometimes referred to as the Rumack–Matthew line, starts at 200 μg/mL at 4 hours and was published in 1975 by Barry H. Rumack and Henry Matthew. When the NAC study began in 1976, the FDA required a line that was 25% below the original.
What is the Rumack Matthew line on a drug screen?
The upper line of the nomogram is the “probable” line, also known as the Rumack-Matthew line. About 60% of patients with values above this line develop hepatotoxicity. The lower line on the nomogram is the “possible” line, which was subsequently added later per request of the U.S. FDA.