Acute isopropyl alcohol intoxication. Diagnosis and management

Isopropyl Alcohol Intoxication Treated With Hemodialysis: A Case Report and Short Review

Isopropyl alcohol (IPA) is a common constituent of rubbing alcohol, household cleaning agents, and antiseptic agents. Ingestion of IPA usually leads to self-resolving mild symptoms in most cases but can result in severe symptoms, including central nervous system depression or hemodynamic instability. Treatment is mainly supportive, and hemodialysis is generally reserved for severe intoxication. Limited data are available on the use of hemodialysis to treat IPA intoxication. We are presenting a case of accidental ingestion of IPA in an elderly female with dementia leading to severe intoxication requiring hemodialysis at relatively non-toxic serum levels of IPA. The patient had a prompt recovery without any post-procedural or hospital-acquired complications.

Lessons of the month 3: Intravenous poppers abuse: case report, management and possible complications

BACKGROUND

Poppers are nitrite-containing liquids, which are inhaled for their aphrodisiac and hallucinogenic effects. Despite some cases of severe poisonings, poppers are often perceived as harmless by consumers. Inhalation and ingestion of poppers are well known, but, according to our literature review, intravenous abuse has not been reported before.

CASE PRESENTATION

A 34-year-old man injected poppers intravenously for recreational purposes. He then suffered from dyspnoea and general discomfort. Upon arrival of emergency medical services, the patient was dyspnoeic with blue-grey skin colour and oxygen saturation was 82% on ambient air. Non-invasive ventilation was necessary, and he was transferred to the intensive care unit. Toluidine blue was administered because of a methaemoglobinaemia of 40% and methaemoglobin levels dropped to 0.4%. He was discharged home after a 24-hour observation. We additionally analysed the contents of the poppers bottle: isopropyl nitrite, isopropanol and acetone were detected. Possible complications and the treatment regarding intravenous administration of poppers are discussed.

CONCLUSION

We present the first published case of intravenous poppers abuse. Our patient suffered from methaemoglobinaemia and was rapidly discharged after treatment with toluidine blue. No specific treatment regarding the contents of the poppers bottle, apart from isopropyl nitrite, was necessary.

Putatively lethal ingestion of isopropyl alcohol-related case: interpretation of post mortem isopropyl alcohol and acetone concentrations remains challenging

Isopropyl alcohol, or propan-2-ol (IPA), is found in numerous chemicals including alcohol-based hand rubs whose use has been recently widely extended to the general population since the onset of the COVID-19 pandemic. This widespread of IPA use could potentially, but not necessarily, be responsible for an increase in IPA poisoning cases (e.g., in alcoholics and/or for suicide attempt, even more in a lockdown situation). Forensic identification of IPA-related fatalities remains challenging as IPA post mortem detection can also result from antemortem or post mortem production, or post mortem contamination. In order to illustrate this issue, we report the case of a 33-year-old man found dead with a bottle of pure IPA liquid close to him. Toxicological positive results only consisted in IPA (464, 260, 465 and 991 mg/L) and acetone (1560, 2340, 3040 and 1360 mg/L) in blood, vitreous humour, urine and bile, respectively (determinations using headspace gas chromatography with flame ionization detection). These IPA absolute concentrations and IPA-to-acetone ratios appear inferior to those usually reported in the literature (higher than 1000 mg/L and 1.1, respectively) in IPA poisoning cases. In conclusion, this death can be cautiously regarded as an IPA ingestion-related fatality in the hypothesis of a survival time which have promoted IPA metabolism to acetone: this hypothesis is supported by the putative limited IPA-ingested dose. This report emphasizes the fact that post mortem IPA and acetone concentration interpretation involves to take account of (i) results in multiple biological specimens, (ii) complete case history, and (iii) a search of possible IPA presence at the scene of death.

Optical isopropanol biosensor using NADH-dependent secondary alcohol dehydrogenase (S-ADH)

Isopropanol (IPA) is an important solvent used in industrial activity often found in hospitals as antiseptic alcohol rub. Also, IPA may have the potential to be a biomarker of diabetic ketoacidosis. In this study, an optical biosensor using NADH-dependent secondary alcohol dehydrogenase (S-ADH) for IPA measurement was constructed and evaluated. An ultraviolet light emitting diode (UV-LED, λ=340nm) was employed as the excitation light to excite nicotinamide adenine dinucleotide (NADH). A photomultiplier tube (PMT) was connected to a two-way branch optical fiber for measuring the fluorescence emitted from the NADH. S-ADH was immobilized on the membrane to catalyze IPA to acetone and reduce NAD(+) to be NADH. This IPA biosensor shows highly sensitivity and selectivity, the calibration range is from 500 nmol L(-1) to 1mmolL(-1). The optimization of buffer pH, temperature, and the enzyme-immobilized method were also evaluated. The detection of IPA in nail related cosmetic using our IPA biosensor was also carried out. The results showed that large amounts of IPA were used in these kinds of cosmetics. This IPA biosensor comes with the advantages of rapid reaction, good reproducibility, and wide dynamic range, and is also expected to use for clinical IPA detections in serum or other medical and health related applications.

Inhibition of heparin precipitation, bacterial growth, and fungal growth with a combined isopropanol-ethanol locking solution for vascular access devices

BACKGROUND

Clinical reports of ethanol-lock use for the prevention of catheter-related bloodstream infections have been marked by the occurrence of serious catheter occlusions, particularly among children with mediports. We hypothesized that precipitate forms when ethanol mixes with heparin at the concentrations relevant for vascular access devices, but that the use of a combination of two alcohols, ethanol and isopropanol, would diminish heparin-related precipitation, while retaining anti-bacterial and anti-fungal effects.

METHODS

Heparin (0-100units/mL) was incubated in ethanol-water solutions (30%-70% vol/vol) or in an aqueous solution containing equal parts (35% and 35% vol/vol) of isopropanol and ethanol. Precipitation at temperatures from 4 to 40°C was measured in nephelometric turbidity units using a benchtop turbidimeter. Growth of Escherichia coli, Staphylococcus aureus, and Candida albicans colonies were measured following exposure to solutions of ethanol or isopropanol-ethanol. Groupwise comparisons were performed using analysis of variance with Bonferroni-corrected, post-hoc T-testing.

RESULTS

Seventy percent ethanol and heparin exhibit dose-dependent precipitation that is pronounced and significant at the concentrations typically used in mediports (p<0.05). Precipitate is significantly reduced by use of a combined 35% isopropanol-35% ethanol solution rather than 70% ethanol (p<0.05), while maintaining the solution's anti-bacterial and anti-fungal properties. On the other hand, although ethanol solutions under 70% form less precipitate with heparin, such concentrations are also less effective at bacterial colony inhibition than solutions of either 70% ethanol or 35% isopropanol-35% ethanol (p<0.05).

CONCLUSIONS

A combined 35% isopropanol-35% ethanol locking solution inhibits bacterial and fungal growth similarly to 70% ethanol, but results in less precipitate than 70% ethanol when exposed to heparin. Further study of a combined isopropanol-ethanol locking solution for the prevention of catheter-related bloodstream infections should focus on the determination as to whether such a locking solution may reduce the rate of precipitation-related catheter occlusion, and whether it may be administered with low systemic toxicity.

Determination of sevoflurane and isopropyl alcohol in exhaled breath by thermal desorption gas chromatography-mass spectrometry for exposure assessment of hospital staff

Volatile anaesthetics and disinfection chemicals pose ubiquitous inhalation and dermal exposure risks in hospital and clinic environments. This work demonstrates specific non-invasive breath biomonitoring methodology for assessing staff exposures to sevoflurane (SEV) anaesthetic, documenting its metabolite hexafluoroisopropanol (HFIP) and measuring exposures to isopropanol (IPA) dermal disinfection fluid. Methods are based on breath sample collection in Nalophan bags, followed by an aliquot transfer to adsorption tube, and subsequent analysis by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). Ambient levels of IPA were also monitored. These methods could be generalized to other common volatile chemicals found in medical environments. Calibration curves were linear (r(2)=0.999) in the investigated ranges: 0.01-1000 ppbv for SEV, 0.02-1700 ppbv for IPA, and 0.001-0.1 ppbv for HFIP. The instrumental detection limit was 10 pptv for IPA and 5 pptv for SEV, both estimated by extracted ion-TIC chromatograms, whereas the HFIP minimum detectable concentration was 0.5 pptv as estimated in SIM acquisition mode. The methods were applied to hospital staff working in operating rooms and clinics for blood draws. SEV and HFIP were present in all subjects at concentrations in the range of 0.7-18, and 0.002-0.024 ppbv for SEV and HFIP respectively. Correlation between IPA ambient air and breath concentration confirmed the inhalation pathway of exposure (r=0.95, p<0.001) and breath-borne IPA was measured as high as 1500 ppbv. The methodology is easy to implement and valuable for screening exposures to common hospital chemicals. Although the overall exposures documented were generally below levels of health concern in this limited study, outliers were observed that indicate potential for acute exposures.

Pseudorenal insufficiency with isopropyl alcohol ingestion

Isopropyl ingestion is usually a benign occurrence with little metabolic or renal abnormalities. We describe a case of a false elevation of serum creatinine due to laboratory interference in the setting of a toxic alcohol exposure that could have led to a misdiagnosis of ethylene glycol intoxication and a different treatment plan. Clinicians should be aware of this laboratory anomaly when treating suspected toxic alcohol ingestions.

Short-term immunological effects of non-ethanolic short-chain alcohols

Short-chain alcohols are embedded into several aspects of modern life. The societal costs emanating from the long history of use and abuse of the prototypical example of these molecules, ethanol, have stimulated considerable interest in its general toxicology. A much more modest picture exists for other short-chain alcohols, notably as regards their immunotoxicity. A large segment of the general population is potentially exposed to two of these alcohols, methanol and isopropanol. Their ubiquitous nature and their eventual use as ethanol surrogates are predictably associated to accidental or deliberate poisoning. This review addresses the immunological consequences of acute exposure to methanol and isopropanol. It first examines the general mechanisms of short-chain alcohol-induced biological dysregulation and then provides a tentative model to explain the molecular events that underlie the immunological dysfunction produced by methanol and isopropanol. The time-related context of serum alcohol concentrations in acute poisoning, as well as the clinical implications of their short-term immunotoxicity, is also discussed.

The dysregulation of the monocyte/macrophage effector function induced by isopropanol is mediated by the defective activation of distinct members of the AP-1 family of transcription factors

Isopropanol is the second most common cause of short-chain alcohol acute intoxication. Nonethanolic short-chain alcohols mediate their immunomodulatory effect by interfering with nuclear factor of activated T cells (NFAT) activation with or without additional activator protein-1 (AP-1) involvement. In the present study, we examined the immunomodulation induced by isopropanol in conditions that are not reliant on NFAT: the inflammatory cytokine response of lipopolysaccharide (LPS)-stimulated monocytes. Our hypothesis was that isopropanol acute exposure would have an attenuated effect or no consequence in this setting. To our surprise, the impairment of AP-1 activation was sufficient to mediate a severe and dose-dependent phenotype in human monocytes in vitro at alcohol concentrations as low as 0.16% (or 26 mM). There were three outcomes: interleukin (IL)-1β/IL-8 were unaltered; IL-6 was upregulated; and tumor necrosis factor alpha (TNF-α)/CCL2 were downregulated. The effector function of human monocyte-derived macrophages was also compromised. Our results showed that Toll-like receptor 4 early signaling was preserved, as isopropanol did not change the kinase activity of the IL-1 receptor-associated kinase 1 in LPS-stimulated cells. The nuclear factor-κB signaling cascade and the p38/c-Jun N-terminal kinase modules of the mitogen-activated protein kinase pathway were alcohol insensitive. Conversely, the activation of extracellular signal-regulated protein kinase and, ultimately, of c-Fos and JunB were impaired. The alcohol-induced cytokine dysregulation was confirmed in a mouse model of isopropanol intoxication in which the production of TNF-α in response to LPS challenge was virtually abolished. The magnitude of this alcohol effect was sufficiently high to rescue animals from LPS-induced toxic shock. Our data contribute to the dismal body of information on the immunotoxicology of isopropanol, one of the most ubiquitous chemicals to which the general population is significantly exposed.

Repeated intoxication presenting with azotemia, elevated serum osmolal gap, and metabolic acidosis with high anion gap: differential diagnosis, management, and prognosis

A man with a history of alcoholism presented on two different occasions with mental changes, clinical signs of volume depletion, elevated serum osmolal gap, metabolic acidosis with high anion gap, metabolic alkalosis, hyponatremia, and azotemia after binge drinking of only ethanol. In both episodes, the serum contained ethanol, acetone, and 2-propanol (isopropanol), but no methanol or ethylene glycol. In the first episode, the rates of excretion of acetoacetate and 3-hydroxybutyrate in the urine were greatly increased. Volume repletion was the only treatment. In both episodes, azotemia and metabolic acidosis were rapidly reversed, while modest metabolic alkalosis was noted after treatment. The triad of azotemia, elevated osmolal gap, and high anion gap metabolic acidosis, which characterizes intoxication with methanol or ethylene glycol, can also develop in alcoholic ketoacidosis (AKA), an entity with substantially different management and outcome. Finding 2-propanol in the serum of patients with AKA indicates either concomitant 2-propanol ingestion or formation of 2-propanol from acetone.

Household chemicals: management of intoxication and antidotes

Exposure to household products is very common, but in industrialized countries severe or fatal poisoning with household products is rare today, due to the legal restriction of sale of hazardous household products. The big challenge for physicians, pharmacologists and toxicologists is to identify the few exceptional life-threatening situations where immediate intervention is needed. Among thousands of innocuous products available for the household only very few are hazardous. Substances found in these products include detergents, corrosives, alcohols, hydrocarbons, and some of the essential oils. The ingestion of batteries and magnets and the exposure to cyanoacrylates (super glue) can cause complications in exceptional situations. Among the most dangerous substances still present in household products are ethylene glycol and methanol. These substances cause major toxicity only through their metabolites. Therefore, initial symptoms may be only mild or absent. Treatment even in asymptomatic patients has to be initiated as early as possible to inhibit production of toxic metabolites. For all substances not only the compound itself but also the route of exposure is relevant for toxicity. Oral ingestion and inhalation generally lead to most pronounced symptoms, while dermal exposure is often limited to mild irritation. However, certain circumstances need special attention. Exposure to hydrofluoric acid may lead to fatal hypocalcemia, depending on the concentration, duration of exposure, and area of the affected skin. Accidents with hydrocarbon pressure injectors and spray guns are very serious events, which may lead to amputation of affected limbs. Button batteries normally pass the gastrointestinal tract without problems even in toddlers; in rare cases, however, they get lodged in the esophagus with the risk of localized tissue damage and esophageal perforation.

[Acute intoxication with isopropanol]

Isopropanol is an ingredient of commonly used industrial and household agents. Intoxication can occur unintentionally, in suicide attempts or by alcohol abusers when used as a substitute for ethanol. Symptoms involve the gastrointestinal tract, the central nervous system, and the cardiovascular system at higher doses. Mortality is especially high in patients with deep coma and marked hypotension. This report describes a case of life-threatening isopropanol intoxication of a prison inmate successfully treated by haemodialysis.

Cerebral sinovenous thrombosis associated with isopropanol ingestion in an infant

This report describes a 5-week-old female infant who presented with accidental ingestion of rubbing alcohol (which contains about 70% isopropanol), and was subsequently diagnosed with cerebral sinovenous thrombosis. Isopropanol is a clear, volatile 3-carbon alcohol found in varying concentrations in many solvents. Mislabeled rubbing alcohol was mixed with this patient's formula. After ingesting it, she presented with a 1-day history of uncontrolled fussiness and an episode of deviation of the eyes to the right for 30 minutes, followed by rhythmic movements of the arms and legs for 20 minutes. Cerebral imaging demonstrated sinovenous thrombosis. To our knowledge, there have been no reports describing cerebral sinovenous thrombosis as a complication of isopropanol ingestion. The possible association of isopropanol ingestion and sinovenous thrombosis is discussed.

A case of mixed intoxication with isopropyl alcohol and propanol-1 after ingestion of a topical antiseptic solution

We report a mixed intoxication with isopropyl alcohol and propanol-1 in a hospitalized patient who ingested, on two separate days, two 100 ml bottles of a topical antiseptic solution containing isopropyl alcohol and propanol-1. Eight hours after the second ingestion, plasma concentrations of isopropanol, propanol-1 and acetone were 37 mg/dL, <10 mg/dL, and 227 mg/dl, respectively. Despite a lack of severe toxicity, 4-methylpyrazole (fomepizole) was initiated. This case points out the need to limit access to alcohol-containing antiseptic solutions on wards where alcoholic and psychotic patients are hospitalized.

Immunosuppressive effect of isopropanol: down-regulation of cytokine production results from the alteration of discrete transcriptional pathways in activated lymphocytes

Isopropanol (IPA) is widely used in household applications and constitutes a leading cause of acute alcohol intoxication second only to ethanol. Although the effects of ethanol on the immune system have been extensively studied, far fewer data are available on IPA. Given the structural similarity between the two molecules, we hypothesized that IPA could as well have immunomodulatory properties. We report here that acute IPA exposure is detrimental to human T lymphocyte and NK cell activity in vitro in concentrations as low as 0.08-0.16% (13-26 mM). IPA treatment did not affect receptor-mediated early signaling but had a reproducible and dose-dependent effect on the nuclear translocation of NFAT and AP-1. Furthermore, we show in a model of acute IPA intoxication that animals became immunosuppressed as judged by their reduced ability to release IL-2 and IFN-gamma in the serum in response to staphylococcal enterotoxin B. This effect was also associated to the down-regulation of TNF-alpha production and was sufficiently strong to rescue susceptible animals from enterotoxin-induced toxic shock. Our results suggest that IPA is potentially immunosuppressive to the adaptive and innate immune system and have broad significance given the exposure of the general population to this ubiquitous chemical.

Poisoning with 1-propanol and 2-propanol

1-Propanol and 2-propanol are isomers of an alcohol with three carbons. They are colorless liquids with a sweet odor. 1-Propanol is metabolized by alcohol dehydrogenase to propionic acid and presents with metabolic acidosis and elevated anion gap, whereas 2-propanol is metabolized by alcohol dehydrogenase to acetone and presents with rapidly developing (within 3-4 h after exposure) ketosis and ketonuria but without metabolic acidosis. We report a patient who simultaneously ingested a lethal dose of 1-propanol and 2-propanol as a hand disinfectant in hospital. The patient lost consciousness and stopped breathing within half an hour after ingestion. He was intubated and artificially ventilated. Initial laboratory results showed mixed acidosis with elevated anion gap, but ketonuria appeared only 12 h after admission and 6 h following the regaining of consciousness. Therefore, laboratory results in simultaneous poisoning with two isomers of alcohol are not just a sum of laboratory results obtained in isolated poisoning with each isomer because they influence each other's metabolism: 1-propanol retards the metabolism of 2-propanol to acetone. In conclusion, 1-propanol and 2-propanol poisoning presents early with mixed acidosis and elevated anion gap and only later with ketonuria.

Toxic alcohol ingestions: clinical features, diagnosis, and management

Alcohol-related intoxications, including methanol, ethylene glycol, diethylene glycol, and propylene glycol, and alcoholic ketoacidosis can present with a high anion gap metabolic acidosis and increased serum osmolal gap, whereas isopropanol intoxication presents with hyperosmolality alone. The effects of these substances, except for isopropanol and possibly alcoholic ketoacidosis, are due to their metabolites, which can cause metabolic acidosis and cellular dysfunction. Accumulation of the alcohols in the blood can cause an increment in the osmolality, and accumulation of their metabolites can cause an increase in the anion gap and a decrease in serum bicarbonate concentration. The presence of both laboratory abnormalities concurrently is an important diagnostic clue, although either can be absent, depending on the time after exposure when blood is sampled. In addition to metabolic acidosis, acute renal failure and neurologic disease can occur in some of the intoxications. Dialysis to remove the unmetabolized alcohol and possibly the organic acid anion can be helpful in treatment of several of the alcohol-related intoxications. Administration of fomepizole or ethanol to inhibit alcohol dehydrogenase, a critical enzyme in metabolism of the alcohols, is beneficial in treatment of ethylene glycol and methanol intoxication and possibly diethylene glycol and propylene glycol intoxication. Given the potentially high morbidity and mortality of these intoxications, it is important for the clinician to have a high degree of suspicion for these disorders in cases of high anion gap metabolic acidosis, acute renal failure, or unexplained neurologic disease so that treatment can be initiated early.

Toxicology in the critically ill patient

Intoxications present in many forms including: known drug overdose or toxic exposure, illicit drug use, suicide attempt, accidental exposure, and chemical or biological terrorism. A high index of suspicion and familiarity with toxidromes can lead to early diagnosis and intervention in critically ill, poisoned patients. Despite a paucity of evidence-based information on the management of intoxicated patients, a rational and systematic approach can be life saving.

On the mammalian acetone metabolism: from chemistry to clinical implications

Despite the description of the ways of acetone metabolism, its real role(s) is (are) still unknown in metabolic network. In this article, a trial is made to ascertain a comprehensive overview of acetone research extending discussion from chemistry to clinical implications. Mammals are quite similar regarding their acetone metabolism, even if species differences can also be observed. By reviewing experimental data, it seems that plasma concentration of acetone in different species is in the order of 10 microm range and the concentration-dependent acetone metabolism is common to all mammals. At low concentrations of plasma acetone, the C3 pathways are operative, while at higher concentrations, the metabolism through acetate becomes dominant. Glucose formation from acetone may also contribute to the maintenance of a constant blood glucose level, but it seems to be only a minor source for that. From energetical point of view, an interorgan cooperation is suggested because transportable C3 fragments produced in the liver can serve as alternative sources of energy for the peripheral tissues in the short of circulating glucose. The degradation of acetoacetate to acetone contributes to the maintenance of pH buffering capacity, as well. Special attention is paid to the discussion of acetone production in diseases amongst which endogenous and exogenous acetonemiae have been defined. Acetonemiae of endogenous origin are due to the increased rate of acetone production followed by an increase of degrading capacity as cytochrome p450IIE1 (CYPIIE1) isozymes become induced. Exogenous acetonemiae usually resulted from intoxications caused by either acetone itself or other exogenous compounds (ethanol, isopropyl alcohol). It is highlighted that, on the one hand, isopropanol is also a normal constituent of metabolism and, on the other hand, the flat opinion that the elevation of its plasma level is a sign of alcoholism cannot further be held. The possible future directions of research upon acetone are depicted by emphasizing the need for the clear-cut identification of mammalian acetoacetate decarboxylase, and the investigation of race differences and genetic background of acetone metabolism.

Hemorrhagic gastritis from topical isopropanol exposure

OBJECTIVE

To report the occurrence of hemorrhagic gastritis after topical isopropanol application in an infant.

CASE SUMMARY

A 2-year-old Hispanic boy developed coffee-ground emesis during emergency department evaluation for lethargy and fever. After an initial inconclusive workup for sepsis, further history revealed an isopropanol rubdown for fever reduction. Isopropanol concentrations and acetone metabolites were elevated, the patient recovered with supportive therapy, and other causes for hemorrhagic gastritis were excluded.

DISCUSSION

Isopropanol sponge bathing is commonly used as a home remedy for infants with fever. Topical absorption of isopropanol has previously been reported to cause mental status changes, ketosis, and metabolic acidosis. We report a case of hemorrhagic gastritis as a complication of topical isopropanol absorption in a febrile infant. An objective causality assessment revealed that the adverse event was probably caused by the isopropanol. Previous reports of pediatric isopropanol poisoning and its management are discussed.

CONCLUSIONS

Severe morbidity from topical isopropanol exposure may occur in young children.

Isopropyl alcohol intoxication: a diagnostic challenge

Isopropyl alcohol (IPA) is an ingredient of commonly used household solutions. Accidental and suicidal ingestion of IPA sometimes can be fatal if it goes unrecognized and untreated. There are few published reports on IPA intoxication. We describe a case of repeated IPA ingestion in a single individual, followed by a review of the literature on the subject. The differential diagnosis, diagnostic pitfalls, and therapeutic interventions in patients with IPA intoxications are discussed.

Extracorporeal therapies for acute intoxications

Intoxications frequently perturb acid-base and electrolyte status, intravascular volume, and renal function. In selected cases, extracorporeal techniques effectively restore homeostasis and augment intoxicant removal. The use of 4-methylpyrazole, an inhibitor of alcohol dehydrogenase, is a new and effective treatment for patients exposed to toxic alcohols. In this section, practical approaches to commonly encountered intoxicants and the use of extracorporeal techniques are critically reviewed.

Treatment of methanol and isopropanol poisoning with intravenous fomepizole

CASE REPORT

We report a case of mixed methanol and isopropanol poisoning in a patient who refused dialysis but agreed to treatment with intravenous fomepizole. The patient was asymptomatic on arrival, with initial blood methanol and isopropanol concentrations of 146 mg/dL and 39 mg/dL, respectively. Blood ethanol was undetectable. The patient was treated with fomepizole twice daily intravenously until blood methanol was undetectable. No side effects of therapy, other than transient eosinophilia, were observed. The evolution was uneventful and no metabolites of either alcohol were detected at any time during the hospitalization. The decay of plasma methanol and isopropanol under fomepizole treatment were well described by first-order kinetics. The plasma elimination half-lives of methanol and isopropanol were 47.6 hours and 27.7 hours, respectively. Fomepizole appears to have been effective in blocking the toxic metabolism of both methanol and isopropanol and was associated with a favorable outcome.

Treatment of the alcohol intoxications: ethylene glycol, methanol and isopropanol

Intoxications with ethylene glycol, methanol, and isopropanol are among the most common ingestions, in the treatment of which a nephrologist plays an important role. These three substances have the ideal characteristics for intervention by hemodialysis, and the three parent compounds and their metabolites are readily dialyzable. Two of the three substances, ethylene glycol and methanol, are metabolized to more toxic substances, so that an early treatment strategy that removes the parent compound or blocks its metabolism can prevent the development of many of the adverse events that are often seen in these ingestions. Fomepizole, an inhibitor of alcohol dehydrogenase, slows the metabolism of these substances and is now approved by the US Food and Drug Administration for use in ethylene glycol intoxication. The present review addresses recent advances in the diagnosis and treatment of intoxication with ethylene glycol, methanol and isopropanol.

Detection of isopropyl alcohol in a patient with diabetic ketoacidosis

A 29-year-old man presented to the Emergency Department with acute mental status changes. He was unable to give a history. He was found to be in diabetic ketoacidosis, although his family reported no prior history of diabetes. A toxic exposure work-up revealed the presence of isopropyl alcohol in the patient's blood. His condition improved with treatment of the ketoacidosis, and he subsequently denied any exposure to isopropyl alcohol prior to presentation to the hospital. This case provides further support to a growing body of evidence that the detection of isopropyl alcohol may not represent an acute ingestion but, rather, a byproduct of acetone metabolism in certain disease states.

Accidental isopropanol ingestion in children

OBJECTIVE

To describe the clinical course and determine the minimal observation period required following isopropanol ingestion in children.

METHODS

The emergency department records of children less than 6 years of age with isopropanol ingestion who presented between June 1992 and December 1998 were identified. Demographics, type, and amount of ingested substance, and time of ingestion were recorded. Symptoms, time of onset, and the results of physical examination and laboratory tests were collected. Group 1 included patients who did not have isopropanol level assayed, and group 2 members had isopropanol level assayed.

RESULTS

Ninety-one cases of isopropanol ingestion were identified. Clinical evidence of toxicity was noted in 26 (29%) patients. Symptoms included spontaneous emesis in (24/26), ataxia (5/26), altered mental status (3/26), and apnea (1/26). Toxic isopropanol levels were noted in three patients; all had altered mental status. Clinical evidence of toxicity developed between 0.5 and 2 hours post-ingestion. Patients who ingested more than 1 ounce of isopropanol were more likely to become symptomatic (RR 4.26, 95% CI = 1.61-11.2).

CONCLUSIONS

An observation period of 2 hours post-ingestion can be used to rule out clinical toxicity in pediatric patients with suspected isopropanol ingestion. Patients with a history of ingesting more than 1 ounce are likely to develop adverse clinical effects. The development of altered mental status is the most useful clinical predictor of a toxic blood isopropanol level.

Fatal inhalational isopropyl alcohol poisoning in a neonate

A 37 weeks gestation, 1500 gram male infant with multiple dysmorphic features underwent surgery for gastroschisis several hours after birth. During post-operative mechanical ventilation, 70% isopropyl alcohol was accidentally placed in the humidifier of the ventilator, resulting in an estimated 2 h exposure. While the baby seemed clinically stable, initial neurological examination was confounded by recent sedation and pancuronium paralysis. Initial post-operative hypotension was corrected with fluid administration and remained stable for the remainder of the clinical course. By 2 h post-exposure, he was moving, breathing spontaneously and opening his eyes. Isopropyl alcohol and acetone levels at 1, 6, 10 h post exposure were 31/10, 22/15, 15/20 mmol/L respectively. Isopropyl alcohol elimination t1/2 was 9.6 h. Dialysis or exchange transfusion were considered but due to their high risk and the stable infant condition, it was elected to continue with supportive care only. 12.5 h post-exposure, he suddenly became cyanotic, bradycardic, then asystolic. Resuscitation efforts were unsuccessful. To our knowledge, this is the youngest patient reported to have toxic inhalational exposure to isopropyl alcohol and the first report on isopropyl alcohol pharmacokinetics at this age.

Acute isopropanol ingestion: pharmacokinetic parameters in the infant

We describe a case of isopropanol intoxication in a 2-month-old infant. The source of isopropanol and both the route and time of ingestion could be clearly identified. Serial measurements of isopropanol and acetone provided data for calculating their respective elimination half-lives. Isopropanol (half-life = 5.8 hr) clearance was similar to values reported for adults; acetone (half-life = 10.8 hr) was eliminated twice as rapidly as in adults.

Serum determinations in toxic isopropanol ingestion

A toxic dose of isopropyl alcohol was ingested by six male mongrel dogs to evaluate the relationship between acetone production and isopropyl degradation. Maximal serum isopropyl levels were achieved approximately 2 to 3 hours after ingestion of 60 mL of 70% isopropyl alcohol. Acetonemia occurred rapidly in the serum (within 15 minutes of ingestion) and continued to rise after isopropanol levels plateaued. The levels of acetone and isopropanol correlated positively throughout the study model with an r of .54 (P less than .001). It is concluded that there is a positive relationship between acetone production and isopropyl metabolism in the setting of a toxic ingestion of isopropanol. Acetone's persistence as a serum marker may be beneficial in identifying isopropyl hours after a suspected ingestion.

Isopropanol ingestion: a report of six episodes with isopropanol and acetone serum concentration time data

The disposition of isopropanol and its major metabolite acetone were observed in six isopropanol ingestion episodes among five patients. Serum admission isopropanol and peak acetone concentrations ranged from 16.5 to 220 mg/dL and 141 to 585 mg/dL respectively. Ingestions ranged from 120 to 300 mL of 70% isopropanol with concomitant ethanol ingestion in two episodes. The isopropanol and acetone apparent half-lives ranged from 2.9 to 16.2 hours (h) and 7.6 to 26.2 h respectively. Two episodes of isopropanol ingestion were observed within a 9 month period in patient one. Isopropanol terminal elimination rate constants were 0.043 and 0.085 per hour (per h) with no marked difference in acetone terminal elimination rate constants (0.025 and 0.033 per h). Discrepancy between the two isopropanol elimination rate constants reflected concomitant ethanol abuse with the first ingestion. Reductions in isopropanol and acetone half-lives were also noted among patients requiring ventilatory support.

Detection of isopropanol in acetonemic patients not exposed to isopropanol

Isopropanol has been identified in five acetonemic patients not exposed to this compound. Serum concentrations ranged up to 297 mg/L for IPA and up to 321 mg/L for acetone. Concentration ratios (isopropanol:acetone) ranged up to 5.12. All five patients had Type I diabetes mellitus and were insulin-dependent. At the time isopropanol was detected each patient was hyperglycemic, and four patients were acidotic. These findings tend to corroborate clinically some earlier autopsy reports that acetone may be converted to isopropanol in physiological conditions in which reduced nicotinamide adenine dinucleotide is elevated. The conversion of acetone to isopropanol in vivo has significant clinical and forensic toxicological implications.