Delayed Salicylate Toxicity at 35 Hours Without Early Manifestations Following a Single Salicylate Ingestion

Timely Hemodialysis for Successful Treatment of Acute Salicylate Overdose in a Young Adult Female - A Case Report

Salicylates are often used in clinical practice as antiplatelets as well as analgesics. Its overdose is not uncommon due to its easy availability over the counter. Mortality is high in severe cases when a lethal dose is consumed. Treatment of overdose is difficult due to the non-availability of an antidote. Hemodialysis is an underutilized treatment modality in such cases. We discuss here a case of a young female who presented to us 2.5 h after the consumption of a lethal dose of salicylate with symptoms of only tinnitus. She was successfully treated with two sessions of hemodialysis. Her drug levels on admission were remarkably high, and early hemodialysis was justified in view of high-dose consumption with minimal symptoms.

Clinical and Forensic Aspects of Pharmacobezoars

BACKGROUND

Pharmacobezoars are specific types of bezoars formed when medicines, such as tablets, suspensions, and/or drug delivery systems, aggregate and may cause death by occluding airways with tenacious material or by eluting drugs resulting in toxic or lethal blood concentrations.

OBJECTIVE

This work aims to fully review the state-of-the-art regarding pathophysiology, diagnosis, treatment, and other relevant clinical and forensic features of pharmacobezoars.

RESULTS

Patients of a wide range of ages and of both sexes present with signs and symptoms of intoxications or more commonly gastrointestinal obstructions. The exact mechanisms of pharmacobezoar formation are unknown but are likely multifactorial. The diagnosis and treatment depend on the gastrointestinal segment affected and should be personalized to the medication and the underlying factor. A good and complete history, physical examination, image tests, upper endoscopy, and surgery through laparotomy of the lower tract are useful for diagnosis and treatment.

CONCLUSION

Pharmacobezoars are rarely seen in clinical and forensic practice. They are related to controlled or immediate-release formulations, liquid, or non-digestible substances, in normal or altered digestive motility/anatomy tract, and in overdoses or therapeutic doses, and should be suspected in the presence of risk factors or patients taking drugs which may form pharmacobezoars.

Salicylate Intoxication in an Infant: A Case Report

In children, the most common cause of an elevated anion gap (AG) with ketonemia, ketonuria, hyperglycemia, and glycosuria is diabetic ketoacidosis. However, when the clinical history is not clear, other causes must be considered. A 9-month-old girl was transferred to our pediatric intensive care unit (PICU) because of severe metabolic acidosis. On admission, she presented with Kussmaul breathing, tachycardia, irritability, and fever. Blood gasses revealed metabolic acidosis with superimposed respiratory alkalosis and elevated AG. Fluid replacement and bicarbonate for urine alkalinization were started. Ketonemia, acidic urine with glycosuria, ketonuria, and high blood glucose prompted an insulin infusion. Measurement of plasma salicylate confirmed toxic levels. When confronted, the parents admitted to accidentally preparing the child’s bottle with water containing salicylic acid 1000 mg. Although the incidence of salicylate intoxication has declined, it remains an important cause of pediatric morbidity and mortality.

Delayed Salicylate Toxicity in a 17-Year-Old Girl With Initially Undetectable Salicylate Concentration 3.9 Hours After Ingestion

We report the case of a 17-year-old girl with a 126-mg/kg nonenteric coated aspirin ingestion with nontoxic salicylate concentrations at 1.5 and 3.9 hours postingestion, who developed tinnitus and vomiting an estimated 8 hours postingestion, and who was subsequently found to have a toxic salicylate concentration at 22.7 hours postingestion. This case, as well as previous cases of delayed aspirin therapy, may prompt providers to consider educating patients and their care providers regarding the need to return for further testing if symptoms, such as vomiting or tinnitus, develop after an aspirin ingestion.

Hypercapnea and Acidemia despite Hyperventilation following Endotracheal Intubation in a Case of Unknown Severe Salicylate Poisoning

Salicylates are common substances for deliberate self-harm. Acute salicylate toxicity is classically associated with an initial respiratory alkalosis, followed by an anion gap metabolic acidosis. The respiratory alkalosis is achieved through hyperventilation, driven by direct stimulation on the respiratory centers in the medulla and considered as a compensatory mechanism to avoid acidemia. However, in later stages of severe salicylate toxicity, patients become increasingly obtunded, with subsequent loss of airway reflexes, and therefore intubation may be necessary. Mechanical ventilation has been recommended against in acute salicylate poisoning, as it is believed to take away the compensatory hyperpnea and tachypnea. Despite the intuitive physiological basis for this recommendation, there is a paucity of evidence to support it. We describe a case of a 59-year-old male presenting with decreased level of consciousness and no known history of ingestion. He was intubated and experienced profound hypercarbia and acidemia despite mechanical ventilation with high minute ventilation and tidal volumes. This case illustrates the deleterious effects of intubation in severe salicylate toxicity.

Absorption of salicylate powders versus tablets following overdose: a poison center observational study

BACKGROUND

Salicylate absorption following overdose of aspirin (ASA) tablet formulations can be prolonged for greater than 24 h. Accordingly, serial serum concentrations are typically recommended to guide treatment. However, there are little published data on absorption following ingestion of powder ASA formulations, and it is not known if delayed ASA absorption occurs following overdose of powder formulations. The objective of this study is to compare the absorption characteristics of powder and tablet formulations of ASA in patients reported to a single poison center.

METHODS

Electronic records from an accredited poison center were searched for single substance acute or acute on chronic ingestions of ASA in powder form between 1 January 2002 and 31 January 2014. An identical search for ingestions of ASA tablet products between 1 January 2012 and 31 December 2013 was undertaken as the comparator group. Other inclusion criteria were age >12 years, documented time of ingestion, treatment in a health care facility within nine hours of ingestion and at least two detectable serum salicylate concentrations.

RESULTS

16 of 25 powder and 22 of 49 tablet cases met inclusion criteria for analysis. Repeat serum salicylate concentrations following ingestion of tablets increased or insignificantly changed in 11 of 22 (50%) cases, and median serum salicylate concentrations in followed cases remained elevated for up to 12 h in some cases. In comparison, serum salicylate concentrations following powder ingestions declined in 15 of 16 (94%) cases. One patient, who ingested a powder product, underwent hemodialysis pursuant to an initial serum salicylate concentration of 96 mg/dL.

CONCLUSIONS

In contrast to persistent concentrations following overdose of tablets, the majority of serum salicylate concentrations declined following ingestion of powder formulations. In this small study population, these findings suggest that prolonged absorption is unlikely following ingestions of ASA powders.

Late Metabolic Acidosis Caused by Renal Tubular Acidosis in Acute Salicylate Poisoning

A 16-year-old man was transferred to our emergency department seven hours after ingesting 486 aspirin tablets. His blood salicylate level was 83.7 mg/dL. He was treated with fluid resuscitation and sodium bicarbonate infusion, and his condition gradually improved, with a decline in the blood salicylate level. However, eight days after admission, he again reported nausea, a venous blood gas revealed metabolic acidosis with a normal anion gap. The blood salicylate level was undetectable, and a urinalysis showed glycosuria, proteinuria and elevated beta-2 microglobulin and n-acetyl glucosamine levels, with a normal urinary pH despite the acidosis. We diagnosed him with relapse of metabolic acidosis caused by renal tubular acidosis.

Toxicology in the ICU: Part 2: specific toxins

This is the second of a three-part series that reviews the generalized care of poisoned patients in the ICU. This article focuses on specific agents grouped into categories, including analgesics, anticoagulants, cardiovascular drugs, dissociative agents, carbon monoxide, cyanide, methemoglobinemia, cholinergic agents, psychoactive medications, sedative-hypnotics, amphetamine-like drugs, toxic alcohols, and withdrawal states. The first article discussed the general approach to the toxicology patient, including laboratory testing; the third article will cover natural toxins.

Salicylate intoxication: a clinical review

Salicylates are widely used and are easily available as over-the-counter medications; thus, they can be readily abused. Although acute toxicity can be readily diagnosed if an ingestion history is provided, both acute and chronic salicylate toxicity often goes unrecognized, with high mortality when the patient is not treated properly. Salicylates should be considered in the differential diagnosis of an adult patient with acid-base abnormalities of uncertain cause, especially when there are concurrent neurologic symptoms. Patients with salicylate toxicity are treated with alkaline diuresis and sometimes dialysis. The prognosis depends on prompt recognition and treatment. Delayed diagnosis results in increased morbidity and mortality, particularly in the elderly.

Emergency department management of the salicylate-poisoned patient

Salicylate toxicity continues to be encountered commonly in emergency medicine. This article portrays the signs and symptoms of salicylate toxicity, reviews the erratic absorption and elimination kinetics, describes the devastating physiologic effects of overdose, and illustrates the potentially subtle manifestations of chronic aspirin toxicity.

Salicylate poisoning: an evidence-based consensus guideline for out-of-hospital management

A review of U.S. poison center data for 2004 showed over 40,000 exposures to salicylate-containing products. A guideline that determines the conditions for emergency department referral and pre-hospital care could potentially optimize patient outcome, avoid unnecessary emergency department visits, reduce health care costs, and reduce life disruption for patients and caregivers. An evidence-based expert consensus process was used to create the guideline. Relevant articles were abstracted by a trained physician researcher. The first draft of the guideline was created by the lead author. The entire panel discussed and refined the guideline before distribution to secondary reviewers for comment. The panel then made changes based on the secondary review comments. The objective of this guideline is to assist poison center personnel in the appropriate out-of-hospital triage and initial out-of-hospital management of patients with a suspected exposure to salicylates by 1) describing the process by which a specialist in poison information should evaluate an exposure to salicylates, 2) identifying the key decision elements in managing cases of salicylate exposure, 3) providing clear and practical recommendations that reflect the current state of knowledge, and 4) identifying needs for research. This guideline is based on an assessment of current scientific and clinical information. The expert consensus panel recognizes that specific patient care decisions may be at variance with this guideline and are the prerogative of the patient and the health professionals providing care, considering all of the circumstances involved. This guideline does not substitute for clinical judgment. 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 a salicylate, should be referred to an emergency department immediately. This referral should be guided by local poison center procedures. In general, this should occur regardless of the dose reported (Grade D). 2) The presence of typical symptoms of salicylate toxicity such as hematemesis, tachypnea, hyperpnea, dyspnea, tinnitus, deafness, lethargy, seizures, unexplained lethargy, or confusion warrants referral to an emergency department for evaluation (Grade C). 3) Patients who exhibit typical symptoms of salicylate toxicity or nonspecific symptoms such as unexplained lethargy, confusion, or dyspnea, which could indicate the development of chronic salicylate toxicity, should be referred to an emergency department (Grade C). 4) Patients without evidence of self-harm should have further evaluation, including determination of the dose, time of ingestion, presence of symptoms, history of other medical conditions, and the presence of co-ingestants. The acute ingestion of more than 150 mg/kg or 6.5 g of aspirin equivalent, whichever is less, warrants referral to an emergency department. Ingestion of greater than a lick or taste of oil of wintergreen (98% methyl salicylate) by children under 6 years of age and more than 4 mL of oil of wintergreen by patients 6 years of age and older could cause systemic salicylate toxicity and warrants referral to an emergency department (Grade C). 5) Do not induce emesis for ingestions of salicylates (Grade D). 6) Consider the out-of-hospital administration of activated charcoal for acute ingestions of a toxic dose if it is immediately available, no contraindications are present, the patient is not vomiting, and local guidelines for its out-of-hospital use are observed. However, do not delay transportation in order to administer activated charcoal (Grade D). 7) Women in the last trimester of pregnancy who ingest below the dose for emergency department referral and do not have other referral conditions should be directed to their primary care physician, obstetrician, or a non-emergent health care facility for evaluation of maternal and fetal risk. Routine referral to an emergency department for immediate care is not required (Grade C). 8) For asymptomatic patients with dermal exposures to methyl salicylate or salicylic acid, the skin should be thoroughly washed with soap and water and the patient can be observed at home for development of symptoms (Grade C). 9) For patients with an ocular exposure of methyl salicylate or salicylic acid, the eye(s) should be irrigated with room-temperature tap water for 15 minutes. If after irrigation the patient is having pain, decreased visual acuity, or persistent irritation, referral for an ophthalmological examination is indicated (Grade D). 10) Poison centers should monitor the onset of symptoms whenever possible by conducting follow-up calls at periodic intervals for approximately 12 hours after ingestion of non-enteric-coated salicylate products, and for approximately 24 hours after the ingestion of enteric-coated aspirin (Grade C).