Nathanael J. McKeown

Iatrogenic lipid emulsion overdose in a case of amlodipine poisoning.

Introduction. Intralipid therapy has been used successfully as “rescue therapy” in several cases of overdose. We present a case of iatrogenic lipid emulsion overdose because of a dosing error. Case Report. A 71-year-old female overdosed on 27 tablets of 5 mg amlodipine. Although initially stable in the Emergency Department, she became hypotensive, oliguric, and respiratory failure developed despite medical therapy. The primary treating team felt that meaningful recovery was unlikely to occur without rapid improvement in clinical status, and 12.5 h after presentation, intralipid rescue therapy was initiated. A protocol for intralipid specifying a maximum infusion of 400 mL of 20% lipid emulsion was faxed, but the infusion was continued until 2 L of lipid emulsion was infused. There were no detectable adverse hemodynamic effects of the intralipid infusion. After this time, laboratory values were difficult to obtain. Three hours after the infusion, a metabolic panel was obtained from ultracentrifuged blood showing hyponatremia. A white blood cell (WBC) was obtained from a complete blood count (CBC) performed 22 h after the infusion, hemoglobin and hematocrit could not be obtained from this blood. A platelet count was obtained by smear estimate. Hematocrits were obtained from centrifuged blood and appeared elevated. No oxygenation could be obtained on blood gas. The patients family chose to withdraw care on hospital day 2 and no further laboratory draws were obtained. Amlodipine was 1,500 ng/mL (ref. 3–11 ng/mL). Discussion. Lipid emulsion overdose caused no detectable acute adverse hemodynamic effects. The following laboratory values were unobtainable immediately after infusion: white blood cell count, hemoglobin, hematocrit, platelet count, and a metabolic panel of serum electrolytes. Ultracentrifugation of blood allowed for detection of a metabolic panel 3 h after the infusion. Centrifuged hematocrits appeared to be higher than expected.

Is maternal opioid use hazardous to breast-fed infants?

Over the last few decades, the rate of breastfeeding has increased steadily in the developed countries of the world. During this time, opioid use in the general population has steadily increased as well. Despite this, clinicians remain unclear whether opioid use is safe during breastfeeding. While the vast majority of medications used during breastfeeding occur without incident, case reports and studies have reported possible opioid toxicity in breast-fed infants. Multiple enzymes are involved in the metabolism of opioids. CYP2D6 catabolizes O-demethylation of codeine, tramadol, oxycodone, and hydrocodone to more potent metabolites. CYP3A4 inactivates methadone, meperidine, and buprenorphine. Glucoronide conjugation by the UGT enzyme family inactivates morphine and hydromorphone. Genetic polymorphisms and interfering medications affect the maternal metabolism, which in turn determines the exposure and risk to the breast-fed neonate. We review the production of breast milk, the transfer of xenobiotics from blood to milk, the characteristics that alter xenobiotic breast-milk concentrations, and we review the evidence of specific common opioids and infant toxicity. The short-term maternal use of prescription opioids is usually safe and infrequently presents a hazard to the newborn.

Hydrogen peroxide ingestion associated with portal venous gas and treatment with hyperbaric oxygen: a case series and review of the literature

Introduction. Ingestion of concentrated hydrogen peroxide (H2O2) has been associated with venous and arterial gas embolic events, hemorrhagic gastritis, gastrointestinal bleeding, shock, and death. Although H2O2 is generally considered a benign ingestion in low concentrations, case reports have described serious toxicity following high concentration exposures. Hyperbaric oxygen (HBO) has been used with success in managing patients suffering from gas embolism with and without manifestations of ischemia. Methods. Poison center records were searched from July 1999 to January 2010 for patients with H2O2 exposure and HBO treatment. Cases were reviewed for the concentration of H2O2, symptoms, CT scan findings of portal gas embolism, HBO treatment, and outcome. Results. Eleven cases of portal gas embolism were found. Ages ranged from 4 to 89 years. All but one ingestion was accidental in nature. In 10 cases 35% H2O2 was ingested and in 1 case 12% H2O2 was ingested. All abdominal CT scans demonstrated portal venous gas embolism in all cases. Hyperbaric treatment was successful in completely resolving all portal venous gas bubbles in nine patients (80%) and nearly resolving them in two others. Ten patients were able to be discharged home within 1 day, and one patient had a 3.5-day length of stay. Conclusions. HBO was successful in resolving portal venous gas embolism from accidental concentrated H2O2 ingestions.

Complete heart block and death following lamotrigine overdose

Context. Lamotrigine is used for both seizure and psychiatric disorders. Overdoses typically follow a benign course. Case details. A 19-year-old male with bipolar disorder ingested 4 g of lamotrigine. The patient suffered from multiple seizures, charcoal aspiration, respiratory arrest, prolongaton of the QRS interval on electrocardiogram, complete heart block, multiorgan failure and ultimately death. Discussion. We describe the emergency department (ED) and ICU course for this patient and briefly review the toxic effects of lamotrigine and the pharmacokinetics with and without hemodialysis.

Muscle spasm associated with therapeutic use of Cang Er Zi Wan

Introduction. Cang Er Zi Wan (CEZW) is a herbal medication derived from Xanthium sibiricum that is used to treat allergies and upper respiratory problems. Its toxicity has been described in grazing animals, in experimental studies, and in human overdoses. We describe a case of muscular spasm that was associated with the therapeutic use of CEZW. Case report. A 17-year-old female was prescribed CEZW for chronic allergies. Shortly after her second dose of 10 pills BID, she developed intermittent muscular spasms. She was seen in an Emergency Department and had normal vital signs and no significant laboratory abnormalities. Her physical exam was significant only for intermittent spasm of the muscles of the face, neck, and upper extremities. No tremor, fasciculation, dystonia, akisthisia, chorea, bradykinesia, or clonus was noted. She discontinued the CEZW and the symptoms slowly decreased over 4 days. Testing of the product did not detect any other medications or drugs. Discussion. CEZW is a herbal medication that contains X. sibiricum. X. sibiricum is a widespread weed that has caused muscular spasm, seizures, and death in animals that graze on it as well as animals experimentally exposed to it. Eleven cases of accidental human ingestion of Xanthium leading to spasm, somnolence, hypoglycemia, renal, and liver toxicity have been described. We describe a unique case of isolated muscular spasms because of the therapeutic use of a CEZW product.

Acute arsenic trioxide ant bait ingestion by toddlers

Introduction. Arsenic trioxide is available for home use in ant baits. Potential arsenic toxicity from unintentional pediatric ingestion is not well studied. The goal of this study is to describe the clinical course and urinary arsenic concentrations of children who ingested ant bait containing arsenic trioxide (0.46%). Methods. This is a case series of pre-school children who unintentionally ingested arsenic trioxide ant bait gel bars in the home reported to two U.S. poison control centers from January 2003 to July 2007. Results. Six children (age range, 8 months to 4 years) ingested varying portions of ant bait gel bars containing arsenic trioxide (0.46%). All vomited shortly after exposure. The initial, pre-chelation urine total arsenic concentrations ranged from 1,858 to 13,981 mcg/L. All children had resolution of symptoms and received chelation with succimer. Follow-up urine arsenic concentrations were in the normal range 14–35 days after chelation and no further clinical toxicity was noted. Conclusions. Children who ingest all or part of a household ant bait gel bar that contains relatively low concentration of arsenic trioxide can develop markedly elevated urine arsenic concentrations with minor initial symptoms. Prompt chelation with succimer is recommended for children with these exposures and continued until urine arsenic concentrations are normal.

Acute lung injury following refrigeration coil deicing.

We report a case of a worker who developed ALI requiring mechanical ventilatory support after attempting to melt ice condensate by applying the flame of an oxy-acetylene torch to refrigeration coils charged with a halocarbon refrigerant in a closed environment. A discussion of possible etiologies are discussed, including phosgene, carbonyl fluoride, and nitrogen oxides. Primary prevention with adequate respiratory protection is recommended whenever deicing is performed in a closed space environment.

Relating calls to US poison centers for potential exposures to medications to Centers for Disease Control and Prevention reporting of influenza-like illness.

Abstract Context: The Centers for Disease Control (CDC) monitors influenza like illness (ILI) and the National Poison Data System (NPDS) warehouses call data uploaded by US poison centers regarding reported exposures to medication. Objective: We examined the relationship between calls to poison centers regarding reported exposures to medications commonly used to treat ILI and weekly reports of ILI. Materials and Methods: The CDC reports ILI, by age group, for each of 10 Health and Human Services (HHS) regions. We examined NPDS summary data from calls reported to poison centers regarding reported exposures to acetaminophen, cough/cold medications, and promethazine, for the same weeks, age groups, and HHS regions for influenza seasons 2000–2013. ILI and NPDS exposures were examined using graphical plots, descriptive statistics, stepwise regression analysis, and Geographic Information Systems (GIS). Results: About 5,101,841 influenza-like illness cases were reported to the CDC, and 2,122,940 calls regarding reported exposures to medications commonly used to treat ILI, were reported by poison centers to the NPDS over the 13 flu seasons. Analysis of stepwise models of the linear untransformed data involving 24 NPDS data groups and for 60 ILI measures, over the 13 influenza seasons, demonstrated that reported exposures to medications used to treat ILI correlated with reported cases of ILI with a median R2 = 0.489 (min R2 = 0.248, max R2 = 0.717), with mean ± SD of R2 = 0.494 ± 0.121. Median number of parameters used (degrees of freedom – 1) was 7. Conclusions: NPDS data regarding poison center calls for selected ILI medication exposures were highly correlated with CDC ILI data. Since NPDS data are available in real time, it provides complimentary ILI monitoring. This approach may provide public health value in predicting other illnesses which are not currently as thoroughly monitored.

From Russia with love - Ingestion of a purple powder

A3-year-old Russian boy is brought into the emergency department by paramedics after ingesting an unknown substance. The substance is a dark purple powder in a clear glass bottle with Russian lettering. Through broken English, the family states the substance was from the boy’s mother and was used as a topical antiseptic. The child has vomited once and is now drooling. Before ingesting this substance, he had been asymptomatic. His medical history is unremarkable; he has no medication allergies and is currently not taking any medications. On physical examination, vital signs show a temperature of 38.0-C, heart rate of 114 beats per minute, respiratory rate of 34 breaths per minute, blood pressure of 94/76 mm Hg, and a hemoglobin oxygen saturation of 99% breathing room air. He is alert and responsive, but has lower lip swelling, mild edema of the tongue with black staining, as well as extensive staining to the mucosa, gums, and teeth. The posterior oropharynx is difficult to see secondary to the staining. His trachea is midline, and there is no stridor present. His breath sounds are clear although he is mildly tachypneic. Cardiac examination is unremarkable. Abdominal palpation is nontender with no masses, and bowel sounds are present. The remainder of his examination is normal. An intravenous line is established, he is given a 20-mL/kg normal saline bolus, and a complete blood count and basic metabolic panel are obtained and are within normal reference ranges.