Ingestion of low-concentration hydrofluoric acid: an insidious and potentially fatal poisoning

Acute Rubigine® Poisoning in Martinique a French Overseas Department of America: Clinical Characteristics and Prognostic Factors

Rubigine® is an anti-rust stain remover containing fluorides which is believed to have been the cause of many deaths in Martinique. However, after the modification of its composition in 2006, serious poisoning from old formulas containing fluorides persisted. Our main objective was to determine the clinical characteristics and prognostic factors of these intoxications. Methods: Any patient admitted to the Martinique University Hospital for acute Rubigine® poisoning was included from 1 January 2000 to 31 December 2016. Usual demographic and clinical data were collected and comparisons between surviving and deceased patients made using a univariate analysis and logistic regression. Results: Fifty-five patients were included (mean age: 43 years; sex ratio M/F: 1.1), and the main clinical characteristics were: changes in electrocardiogram (ECG) (80%), digestive system disorders (75%), and neurological disorders (12%). The main features linked to death were the presence of hydrofluoric acid (p < 0.0001), age over 55 years (p = 0.01), hypocalcemia after the initial intravenous calcium supplementation (p = 0.0003), diarrhea (p < 0.0001), hypersialorrhea (p < 0.0001), myocardial excitability (p < 0.0001), and state of shock (p < 0.0001). Three patients required circulatory support by venous-arterial ECMO. Mortality was 10.9%. Conclusions: Rubigine® poisoning is responsible for significant morbidity and mortality. Fortunately, its incidence as well as mortality has sharply decreased in Martinique thanks to the measures taken by the French state. This retrospective work nevertheless shows that acute intoxication by the old formula of Rubigine® remains the main factor of poor prognosis.

Dermal Hydrofluoric Acid Toxicity Case Review: Looks Can Be Deceiving

Hydrofluoric acid is a caustic compound found in a wide variety of items for household and industrial uses. Dermal exposures can be visually unimpressive on presentation but still have fatal complications. This case review includes a description of a patient presenting with a dermal hydrofluoric acid burn that was effectively treated with topical calcium gluconate gel. Also highlighted are the challenges faced with recognizing the severity and appropriately treating dermal hydrofluoric acid burns in the emergency department.

Missed opportunities?: an evaluation of potentially preventable poisoning deaths

INTRODUCTION

Although most poisoning deaths are not preventable with current medical technology, in some cases different management decisions may have prevented fatal outcomes.

OBJECTIVE

This study aims to review reported poisoning-related deaths for preventability to provide insight to improve future care.

METHODS

Fatality abstracts published in the US National Poison Data System (NPDS) Annual Reports (2008-2012) were analyzed. Preventability was graded using a Likert scale of 1 (definitely non-preventable) to 6 (definitely preventable). Two medical toxicologists screened all cases. Cases deemed definitely not preventable (score 1) by both reviewers were excluded from further review and considered to be "non-preventable". All cases considered at least possibly preventable by either screener were reviewed by a multidisciplinary panel of 5 physicians for preventability scoring. Differences were resolved by consensus. Cases determined to be "preventable" (scores 4-6) were characterized by type of improvement issue involved (diagnosis, treatment, monitoring, other) and recurring scenarios.

RESULTS

Of 390 published abstracts, 78 (20.0%) deaths were considered at least possibly preventable by at least one screener. Of these, 34 (8.7%) deaths were determined to be "preventable" by the panel. Inter-observer agreement by weighted kappa analysis was 0.58 for screening, 0.24 for preventability, and 0.44 for specific aspects of care. The most common toxicants were salicylates (n = 9), opioids (n = 4), toxic alcohols (n = 3), fluoride containing product (n = 3), and bupropion (n = 3). The most common improvement opportunities involved treatment and monitoring.

DISCUSSION

Most of the ingested substances in preventable deaths have delayed GI absorption or require metabolic activation to produce a delayed effect (such as salicylates, opioids, and toxic alcohols), and therefore provide an opportunity for early recognition and successful interventions. Most improvement opportunities are clearly described in the literature but may be not recognized.

CONCLUSIONS

Based on an analysis of published NPDS data, a considerable number of poisoning-related deaths reaching medical attention may be preventable. The most common scenarios involved in potentially preventable poisoning fatalities related to monitoring and treatment. Salicylates and opioids were the most common agents involved in preventable deaths.

Irritant contact dermatitis due to ammonium bifluoride in two infant twins

Ammonium bifluoride is one of the most corrosive acids that may produce severe chemical burns when in contact with skin. This hazardous chemical is widely used in household products. We report two pediatric cases of irritant contact dermatitis after exposure to a rust remover, which contained ammonium bifluoride.

Work-related health emergency cases due to hydrofluoric acid exposures reported to Texas poison centers

OBJECTIVES

Hydrofluoric acid is used in a number of industries. Work-related accidents involving hydrofluoric acid can result in serious injury and death. The intent of this investigation was to describe work-related hydrofluoric acid exposures in Texas.

MATERIALS AND METHODS

Work-related hydrofluoric acid exposures reported to Texas poison centers during 2000-2010 were identified. The distribution of exposures was determined for various demographic and clinical factors.

RESULTS

There were 409 work-related hydrofluoric acid exposures in years 2000-2010. The number of work-related exposures declined from 69 in 2000 to 18 in 2010. The patients were 85.3% male and 96.6% age 20 years or older. The distribution of cases by route of exposure was 69.4% dermal contact, 21.0% inhalation, 12.0% ocular, and 3.7% ingestion. At the time of reporting to Texas poison centers, the patient was already at or en route to a health care facility in 71.9% of the cases and referred to a healthcare facility in 20.5% of the cases. The medical outcome was known or expected to be not serious in 51.6% of the cases.

CONCLUSIONS

Hydrofluoric acid exposures reported to Texas poison centers decreased over the eleven-year period. The patients were almost all adults and primarily male. Most of the exposures occurred by dermal contact followed by inhalation. The majority of patients were managed at healthcare facilities. Slightly over half of the exposures were known or expected to not result in serious outcomes.

A complicated hospitalization following dilute ammonium chloride ingestion

INTRODUCTION

Unintentional ingestions of dilute (<7.5%) cleaning solutions containing ammonium chloride typically do not cause serious harm. We present a case of an intentional ingestion of a dilute ammonium chloride solution resulting in significant morbidity.

CASE REPORT

A 60-year-old woman with bipolar disorder presented one hour after an intentional ingestion of approximately 15 fluid ounces (500 mL) of an algae and odor humidifier treatment containing a total of 2.25% ethyl ammonium chloride. Initial complaints included nausea with a single episode of nonbilious, nonbloody emesis, mild shortness of breath, and chest and epigastric pain. Physical exam was remarkable for bilateral wheezing and epigastric tenderness. An emergent endoscopy demonstrated a Grade 2b caustic injury in the esophagus and a Grade 3b injury in the stomach. Due to persistent cough, copious oral secretions, and worsening hoarseness, the patient was intubated and admitted to the ICU. Her course was complicated by mild hypotension, nonanion gap metabolic acidosis, and oliguria treated successfully with intravenous (IV) fluids. She also developed bilateral pneumonias later in the hospital course. Bedside bronchoscopy showed laryngeal edema and mucosal injury to the segmental level. The patient underwent tracheostomy on hospital day 6. An upper GI swallow study revealed poor esophageal motility in the mid- to lower third of the esophagus. The patient gradually tolerated oral fluids and on hospital day 20 had her tracheostomy tube removed. The patient was subsequently transferred to the psychiatric ward on hospital day 22.

CONCLUSION

Intentional ingestions of dilute ammonium chloride solutions can cause serious injury to the gastrointestinal tract and pulmonary systems, which can result in a complicated and prolonged hospitalization.

Limited efficacy of calcium and magnesium in a porcine model of hydrofluoric acid ingestion

OBJECTIVE

This investigation evaluated the effectiveness of calcium and magnesium in treating oral hydrofluoric acid (HF) poisoning.

METHODS

The controlled laboratory investigation used anesthetized pigs. Subjects received HF via NG tube, titrated to abolish electrocardiographic abnormalities. The untreated group received saline infusion. The treatment group received serial injections of calcium chloride (CaCl2) and magnesium chloride (MgCl2). A third group received oral infusions of Calcium fluoride (CaF2). We measured heart rate, QRS interval, pH, bicarbonate, calcium, magnesium, and potassium. The Wilcoxon Rank Sum test was used to compare intra- and inter-subject differences.

RESULTS

Fatality occurred in all pigs receiving HF. Compared to the untreated group, trends for the treatment group were toward a larger amount of HF to produce fatality (83.1 +/- 17.5 grams vs. 37.7 +/- 16.1 grams, p = 0.08), to cause QRS prolongation (72.5 +/- 25.8vs. 33.8 +/- 14.9 grams, p = 0.08), and to lower potassium at mortality (4.9 +/- 0.7 vs. 8.7 +/- 2.7 mEq/L, p = 0.08). No major changes in calcium (-1.0 +/- 0.7 mEq/L) or magnesium (0.4 +/- 0.6 mEq/L) occurred in the untreated group. Tachycardia developed in all pigs and ventricular arrhythmias occurred in 2 of 3 pigs of both groups [CaF2 administration caused no QRS prolongation or ventricular arrhythmias and had no effect on laboratory parameters].

CONCLUSION

CaCl2 and MgCl2 replacement delayed but did not prevent fatality and QRS prolongation. Although this result suggests Ca++ and Mg++ may be beneficial in the treatment of systemic HF toxicity, factors other than hypocalcemia and hypomagnesemia play a role in toxicity.

Updates on the Evaluation and Management of Caustic Exposures

In 2004, the American Association of Poison Control Centers' Toxic Exposure Surveillance System documented over 200,000 exposures to caustic substances, in both household and industrial products. Although the most commonly affected body areas are the face, eyes, and extremities, all reported fatalities were as a result of ingestion. Little controversy exists in patient management following dermal or ocular caustic exposure. Immediate water irrigation of the site of caustic exposure, followed by routine burn care, analgesia, intravenous fluids, and electrolyte replacement are standards of care. In this manuscript, a thorough review of the management of gastrointestinal caustic exposure is explored, not only because of the high rates of morbidity and mortality associated with these exposures, but also because there remains controversy regarding appropriate management of such exposures. Hydrofluoric acid, a weak acid in its aqueous form, requires special consideration and specific antidotes, and as such, is addressed separately.

Fatality due to acute fluoride poisoning in the workplace

We report a case of a 65-year-old worker who suffered a third-degree skin burn to 5% of his total body surface area as a result of being splashed in the face with hydrofluoric acid (HF). He died shortly thereafter without having received adequate first aid. His serum fluoride concentration was markedly increased at 6.38 mg/dl with hypocalcemia and hyperkalemia. We concluded that he died of HF poisoning. In this case he might have managed to avoid death if he had not been working alone and if he had received adequate first aid on the scene as soon as possible. We re-emphasize the need for the immediate initiation of first aid on the scene and the distribution of information on the risks of HF to workers.

A Simple, Safe, and Efficient Way to Treat Severe Fluoride Poisoning—Oral Calcium or Magnesium

PURPOSE

To examine the efficacy and safety of administration of calcium and magnesium orally and intraperitoneally to treat severe sodium fluoride intoxication.

MATERIALS AND METHODS

Mice were initially gavaged a lethal dose of sodium fluoride (NaF) or water. Then, mice were treated with water or varying concentrations of calcium chloride (CaCl2) or magnesium sulfate (MgSO4) via intraperitoneal (IP) route or via oral route. Mice were monitored for 24 h, and the time of death was recorded.

RESULTS

IP injections of large amounts of CaCl2 or MgSO4 were dangerous. All mice gavaged with water and then treated with oral CaCl2 or MgSO4 survived and displayed normal activity during the experiment. The survival rate of mice gavaged with a lethal dose of NaF and then treated with a high dose of oral CaCl2 or MgSO4 was significantly higher than those of using low dose.

CONCLUSION

Oral administration of a high dose of CaCl2 or MgSO4 is a simple, safe, and effective adjunctive method for treating severe oral fluoride poisoning.

Oral decontamination with calcium or magnesium salts does not improve survival following hydrofluoric acid ingestion

Hydrofluoric acid (HF) ingestion may result in rapid death from systemic fluoride poisoning. Because fluoride binds calcium and magnesium, oral administration of calcium or magnesium salts has been suggested as useful therapy for HF ingestion. This study evaluates oral administration of calcium and magnesium salts for the prevention or attenuation of acute HF toxicity following oral exposure in a mouse model. Mixed breed CF-1 mice were randomized to treatment with a lethal-dose HF premixed with calcium chloride, magnesium sulfate, or deionized water by gavage. Average survival time for the three groups was the same. This study suggests that calcium- or magnesium-containing solutions do not alter the toxic effect of HF following oral exposure.

Calcium neutralizes fluoride bioavailability in a lethal model of fluoride poisoning

OBJECTIVES

Acute systemic fluoride poisoning can result in systemic hypocalcemia, cardiac dysrhythmias, and cardiovascular collapse. Topical and intraarterial therapy with calcium or magnesium salts reduces dermal injury from fluoride burns. The mechanism of these therapies is to bind and inactivate the fluoride ion. The purpose of this study is to evaluate the effect of calcium and magnesium to decrease the bioavailability of fluoride in a lethal model of fluoride poisoning.

METHODS

In preliminary studies, we determined that fluoride 3.6 mM/kg intraperitoneally in the form of sodium fluoride was uniformly and rapidly fatal in a mouse model. Using this fluoride dose, we performed a controlled, randomized, blinded study of low- and high-dose calcium chloride (1.8 and 3.6 mM/kg intraperitoneally, respectively) and magnesium sulfate (3.6 mM/kg intraperitoneally) to decrease the bioavailability of the fluoride ion. After injection with sodium fluoride, animals were immediately treated with injections of sodium chloride (control), calcium chloride (low- or high-dose), or magnesium sulfate. The major outcome was 6-hour survival using a Cox Proportional Hazard model.

RESULTS

All untreated animals died within 60 minutes. Using a Cox Proportional Hazard model, each 1.8 mM/kg dose of calcium chloride administered reduced the risk of death by 33%. Magnesium sulfate treatment was not associated with a hazard reduction.

CONCLUSION

Calcium chloride administered simultaneously with sodium fluoride reduces the bioavailability of fluoride poisoning in a mouse model. The equivalent dose of magnesium sulfate does not significantly decrease fluoride bioavailability.

Pediatric poisonings from household products: hydrofluoric acid and methacrylic acid

Household products continue to be a cause of poisoning morbibidity and mortality. Young children frequently are exposed to cleaning products and cosmetics in the course of exploring their environment. Most of these exposures are insignificant, but some result in death or permanent disability. This review discusses two products that have been responsible for serious injury and death in children: hydrofluoric acid and methacrylic acid. It also discusses federal initiatives designed to protect children from these and other household hazards.