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

Hydrofluoric acid ingestions: Retrospective evaluations from cases reported to the National Poison Data System 2007-2017

Background

Hydrofluoric acid (HF) is associated with systemic toxicity, particularly with high-concentration formulations. However, most existing data describe dermal exposures; there is a paucity of data related to outcomes after ingestions.

Objective

To determine the morbidity and mortality associated with HF ingestions as reported to the National Poison Data System (NPDS). A secondary objective is to assess for clinical criteria that are associated with serious outcomes after HF ingestion.

Methods

We performed a retrospective review of HF ingestions reported to the NPDS from 2007 to 2017. Data including patient demographics, exposure and caller sites, electrolyte abnormalities, treatments, and serious (moderate or major effect or death as documented in NPDS) and non-serious outcomes were abstracted from case narratives. Cases meeting the criteria for a qualifiable HF ingestion were included in the study.

Results

During the study period, there were 653 HF ingestions reported to NPDS, of which 142 were included in the final data analysis. Most HF exposures occurred in men (68.3%), and the most common exposure site was at the exposed individual's own residence (78.2%). Nearly half of all exposures (46.5%) were due to transfer into a non-labeled secondary storage container. Total of 45.8% of the cases resulted in a serious outcome. Electrolyte disturbances were associated with an increased risk of a serious outcome. Hypocalcemia was the most frequently reported electrolyte abnormality, occurring in 24.6% of cases. Nine (6.3%) individuals died.

Conclusions

Mortality after HF ingestion is low. However, a large cohort of exposures occurred after the transfer of HF to secondary containers. Targeted interventions to reduce this practice are necessary to decrease hazardous chemical exposures.

Management of a Man With Hydrofluoric Acid Burns: A Case Report and Review

A hydrofluoric acid (HFA) burn is a severe condition with the characteristics of acute onset, rapid progression, and high complication and mortality rates. Emergency and systemic treatments are especially important for major HFA burns. The author presents the case of a 46-year-old man burned by the spillage of HFA at a high concentration (45-50%). He suffered burns over 30% of his total body area (5% deep partial-thickness burns and 25% third-degree burns). Debridement, tangential excision, and electrolyte therapy were quickly performed for urgent treatment. Symptomatic treatment was sustained to address severe complications and recurrent injury. For successful management, the patient was stabilized, and he exhibited complete wound repair after 3 months. The author summarizes severe cases of HFA burns to emphasize the difficulty of treatment. The existing approved therapies and complications are discussed, and the significance of electrolyte disorders, especially hypocalcemia, is highlighted. The pathophysiology of HFA burns and recommendations for the treatment of HFA burns at different sites are presented to provide a relatively complete treatment guideline focused on electrolyte disorders.

Treatment of Ventricular Fibrillation Due to Ammonium Bifluoride Poisoning With Hemodialysis

Ammonium bifluoride is an inorganic, fluoride-containing compound found in glass and metal etching products, as well as wheel cleaners. Fluoride toxicity is a common cause of preventable poisoning and has been reported to cause life-threatening ventricular dysrhythmias. Here, we report a case of recurrent ventricular fibrillation secondary to ingestion of ammonium bifluoride. The patient presented with vomiting and coma. She was intubated for altered mental status and respiratory failure and subsequently had 5 episodes of ventricular fibrillation, each resolving with a single defibrillation. She developed metabolic acidosis and hypocalcemia, which were treated with sodium bicarbonate and calcium gluconate, respectively. During transfer to a tertiary care children's hospital, ventricular fibrillation recurred despite electrolyte correction. Hemodialysis (HD) was initiated emergently. No further dysrhythmia occurred after initiation of HD. The result of a basic urine drug screen was negative, and a comprehensive drug screen (gas chromatography and mass spectroscopy) revealed only a nonsignificant peak for diphenhydramine. Subsequent laboratory evaluation revealed an elevated serum fluoride level. Diagnostic laryngoscopy and upper endoscopy did not reveal evidence of caustic injury. She was successfully extubated on hospital day 2 and discharged from the hospital on day 4 with no neurologic sequelae. With this example, we demonstrate a potential therapeutic approach to this potentially lethal poisoning. Fluoride toxicity is typically treated with calcium. However, dysrhythmia may result from calcium-independent direct myocardial toxicity. The kinetics of fluoride are amenable to HD, and renal clearance is slow. The potential use of HD in cases of fluoride poisoning refractory to other therapies warrants further study.

Management of a Rare Case With Severe Hydrofluoric Acid Burns: Important Roles of Neutralizers and Continuous Renal Replacement Therapy

Hydrofluoric acid (HF), a dangerous inorganic acid, is widely used in various industries and in daily life. Chemical burns caused by HF exposure occur more frequently in some regions worldwide. It has been reported that some cases with HF burns can be lethal due to the hypertoxicity of HF. In this article, we present a case of a 24-year-old worker who suffered HF burns by 53% HF solution to his face, neck, and nasal cavity. This patient quickly developed electrolyte disturbance, that is, hypocalcemia, and hypopotassemia, and myocardial injury after exposure. Multiple measures had been taken to treat this patient, including fluid resuscitation, electrolyte replacement, timely wound treatment with neutralizers, and respiratory tract care. Moreover, continuous renal replacement therapy was also employed to remove fluoride in the circulatory system and rectify the electrolyte disturbance and acid-base imbalance. The patient smoothly pulled though and survived. High fluoride levels in the dialysate solution were confirmed, indicating that continuous renal replacement therapy is an effective and potentially lifesaving treatment for acute HF poisoning.