Up-to-date treatment of acetaminophen poisoning

N-Acetylcysteine (NAC) is the standard antidote treatment for preventing hepatotoxicity caused by acetaminophen (AAP) poisoning. This review summarizes the recent evidence for the treatment of AAP poisoning. Several alternative intravenous regimens of NAC have been suggested to improve patient safety by reducing adverse drug reactions and medication errors. A two-bag NAC infusion regimen (200 mg/kg over 4 h, followed by 100 mg/kg over 16 h) is reported to have similar efficacy with significantly reduced adverse reactions compared to the traditional 3-bag regimen. Massive AAP poisoning due to high concentrations (more than 300-lines in the nomogram) needs to be managed with an increased maintenance dose of NAC. In addition to NAC, the combination therapy of hemodialysis and fomepizole is advocated for severe AAP poisoning cases. In the case of a patient presenting with an altered mental status, metabolic acidosis, elevated lactate, and an AAP concentration greater than 900 mg/L, hemodialysis is recommended even if NAC is used. Fomepizole decreases the generation of toxic metabolites by inhibiting CYP2E1 and may be considered an off-label use by experienced clinicians. Since the nomogram cannot be applied to sustained-release AAP formulations, all potentially toxic sustained-release AAP overdoses should receive a full course of NAC regimen. In case of ingesting less than the toxic dose, the AAP concentration is tested twice at an interval of 4 h or more; NAC should be administered if either value is above the 150-line of the nomogram.

Rhabdomyolysis induced by venomous snake bite

Purpose@#Despite previous studies reporting the development of rhabdomyolysis (RM), this affliction tends to be neglected as an envenomation sign in South Korea. The current retrospective study investigates the prevalence and prognosis of RM after a snakebite. We further searched for predictors of snakebite-induced RM, which can be observed at presentation. @*Methods@#This study included 231 patients who presented to the ED within 24 hours after a snakebite. The patients were classified according to the severity of RM, and the data, comprising baseline characteristics and clinical course including the level of creatine kinase (CK), were collected and compared according to the severity of RM. @*Results@#The prevalence of RM and severe RM were determined to be 39% and 18.5%, respectively. Compared to the group without RM or with mild RM, the group with severe RM had a higher grade of local swelling, a higher frequency of acute kidney injury and neurotoxicity, and a greater need for renal replacement therapy and vasopressor administration. However, the incidence of acute renal injury in the RM group was 7.7%, with two patients needing renal replacement therapy. No mortalities were reported at discharge. Results of the multinomial logistic regression model revealed that the WBC levels are significantly associated with the risk of severe RM. @*Conclusion@#RM should be considered the primary clinical sign of snake envenomation in South Korea, although it does not seem to worsen the clinical course. In particular, physicians should pay attention to patients who present with leukocytosis after a snakebite, which indicates the risk of developing RM, regardless of the CK level at presentation.

Effects of Paraquat Ban on Herbicide Poisoning-Related Mortality

PURPOSE: In Korea, registration of paraquat-containing herbicides was canceled in November 2011, and sales thereof were completely banned in November 2012. We evaluated the effect of the paraquat ban on the epidemiology and mortality of herbicide-induced poisoning. MATERIALS AND METHODS: This retrospective study analyzed patients treated for herbicide poisoning at 17 emergency departments in South Korea between January 2010 and December 2014. The overall and paraquat mortality rates were compared pre- and post-ban. Factors associated with herbicide mortality were evaluated using logistic analysis. To determine if there were any changes in the mortality rates before and after the paraquat sales ban and the time point of any such significant changes in mortality, R software, version 3.0.3 (package, bcp) was used to perform a Bayesian change point analysis. RESULTS: We enrolled 2257 patients treated for herbicide poisoning (paraquat=46.8%). The overall and paraquat poisoning mortality rates were 40.6% and 73.0%, respectively. The decreased paraquat poisoning mortality rate (before, 75% vs. after, 67%, p=0.014) might be associated with increased intentionality. The multivariable logistic analysis revealed the paraquat ban as an independent predictor that decreased herbicide poisoning mortality (p=0.035). There were two major change points in herbicide mortality rates, approximately 3 months after the initial paraquat ban and 1 year after complete sales ban. CONCLUSION: This study suggests that the paraquat ban decreased intentional herbicide ingestion and contributed to lowering herbicide poisoning-associated mortality. The change point analysis suggests a certain timeframe was required for the manifestation of regulatory measures outcomes.

Does the traditional snakebite severity score correctly classify envenomated patients?

OBJECTIVE: This study aims to help set domestic guidelines for administration of antivenom to envenomated patients after snakebites. METHODS: This retrospective observational case series comprised 128 patients with snake envenomation. The patients were divided into two groups according to the need for additional antivenom after the initial treatment based on the traditional snakebite severity grading scale. One group successfully recovered after the initial treatment and did not need any additional antivenom (n=85) and the other needed an additional administration of antivenom (n=43). RESULTS: The group requiring additional administration of antivenom showed a higher local effect score and a traditional snakebite severity grade at presentation, a shorter prothrombin and activated partial prothrombin time, a higher frequency of rhabdomyolysis and disseminated intravascular coagulopathy, and longer hospitalization than the group that did not need additional antivenom. The most common cause for additional administration was the progression of local symptoms. The independent factor that was associated with the need for additional antivenom was the local effect pain score (odds ratio, 2.477; 95% confidence interval, 1.309 to 4.689). The optimal cut-off value of the local effect pain score was 1.5 with 62.8% sensitivity and 71.8% specificity. CONCLUSION: When treating patients who are envenomated by a snake, and when using the traditional snakebite severity scale, the local effect pain score should be taken into account. If the score is more than 2, additional antivenom should be considered and the patient should be frequently assessed.

Does the Traditional Snakebite Severity Score Correctly Classify the Envenomated Patients with Snake?

PURPOSE: The aim of this study was to help set the domestic guidelines for administration of antivenom to envenomated patients with snake. METHODS: This retrospective observation case series comprised 128 patients with a snake envenomation. The patients were divided into two groups according to the need for additional antivenom after the initial treatment strategy based on the traditional snakebite severity grading scale; one group recovered successfully with the initial treatment decision and did not require an additional antivenom (N=85) and the other group required an additional administration of antivenom later (N=43). RESULTS: The group requiring additional administration of antivenom showed a higher local effect score and traditional snakebite severity grading at presentation, a shorter prothrombin and activated partial prothrombin time, a higher frequency of rhabdomyolysis and disseminated intravascular coagulopathy, and longer hospitalization than the group that did not require an antivenom later. The most common cause of additional administration was the progression of local symptoms. The independent factor associated with the need for additional antivenom administration was a local effect scoring of pain score (odds ratio, 2.477; 95% confidence interval, 1.309 to 4.689). The optimal cut off value of local effect scoring of pain was 1.5 with 62.8% sensitivity and 71.8% specificity. CONCLUSION: The local effect scoring of pain should be considered when treating patients who are envenomated with a snake using the traditional snakebite severity scale. If the local effect scoring of pain is more than 2, an increase of antivenom should be considered and the patients should be assessed frequently.

Clinical Characteristics of Patients after Aryloxyphenoxy Propionate Herbicide Ingestion

PURPOSE: No studies have been conducted to investigate the acute toxicity of aryloxyphenoxypropionate herbicides in humans following ingestion. Therefore, this study was conducted to investigate the clinical characteristics of aryloxyphenoxypropionate herbicide poisoning and provide guidance for physicians treating patients who have ingested these types of herbicides. METHODS: A retrospective observational case series was conducted using ten patients with history of aryloxyphenoxy propionate herbicide. Data were collected for clinical manifestation, management and final outcome. RESULTS: The most common symptoms were gastrointestinal irritation and an altered mental state (Glasgow Coma Scale<15). An elevated lactate level was a common laboratory abnormality, and prolonged QTc interval was commonly observed. These clinical features normalized within one day of supportive treatment. CONCLUSION: The acute toxicity of aryloxyphenoxypropionate herbicides in humans is manageable with supportive treatment. However, physicians should take into account depressed consciousness, the possibility of arrhythmia, and an elevated lactate level when planning their treatment strategy.

The Initial Hyperglycemia in Acute Type II Pyrethroid Poisoning

This retrospective observational case series study was conducted to describe the clinical feature of acute type II pyrethroid poisoning, and to investigate whether hyperglycemia at presentation can predict the outcome in patients with type II pyrethroid poisoning. This study included 104 type II pyrethroid poisoned patients. The complication rate and mortality rate was 26.9% and 2.9% in type II pyrethroid poisoned patients. The most common complication was respiratory failure followed by acidosis and hypotension. In non-diabetic type II pyrethroid poisoned patients, patients with complications showed a higher frequency of hyperglycemia, abnormalities on the initial X ray, depressed mentality, lower PaCO2 and HCO3- levels, and a higher WBC and AST levels at the time of admission compared to patients without complication. Hyperglycemia was an independent factor for predicting complications in non-diabetic patients. Diabetic patients had a significantly higher incidence of complications than non-diabetic patients. However, there was no significant predictive factor for complications in patients with diabetes mellitus probably because of small number of diabetes mellitus. In contrast to the relatively low toxicity of pyrethroids in mammals, type II pyrethroid poisoning is not a mild disease. Hyperglycemia at presentation may be useful to predict the critical complications in non-diabetic patients.