Faculty Bibliography

The United Kingdom's Medicines and Healthcare Products Regulatory Agency (MHRA) modified the indications for N-acetylcysteine therapy of acetaminophen (paracetamol) overdose in September 2012. The new treatment threshold line was lowered to 100 mg/L (662 mumol/L) for a 4 hours acetaminophen concentration from the previous 200 mg/L (1325 mumol/L). This decision has the potential to substantially increase overall costs associated with acetaminophen overdose with unclear benefits from a marginal increase in patients protected from hepatotoxicity, fulminant hepatic failure, death, or transplant. Changing the treatment threshold for acetaminophen overdose also implies that ingestion amounts previously thought not to require acetaminophen concentration measurements would need to be revised. As a result, more individuals will be sent to hospitals in order that everyone with a predicted 4 hours concentration above the 100 mg/L line will have concentrations measured and potentially be treated with N-acetylcysteine. Before others consider adopting this new treatment guideline, formal cost-effectiveness analyses need to be performed to define the appropriate thresholds for referral and treatment.

The use of medicines, with or without medical prescription, for recreational ends by the young population has received little attention from doctors. In the USA, one in five adolescents has used medicines for recreational purposes, and consultations in Emergency Departments for medicine abuse have exceeded those for illegal drugs. Although few data are available in Spain, such consumption is situated between 3.1 and 8.6% according to surveys. The medicines most used are dextromethorphan and methylphenidate. The former, on sale without prescription, presents a varied symptomatology, dosage and dependent metabolic action, ranging from euphoria to hallucinations. Methylphenidate, taken orally, nasally or intravenously, is used as a stimulant in substitution for cocaine and is one of the medicines most diverted onto the illicit market at the world level. In principle, other substances like modafinil and propofol present a limited incidence of non-medical use, but they have a probable abuse potential that should be borne in mind, above all in the health context. Finally, opiates like fentanyl, oxycodone and buprenorphine, with new pharmaceutical presentations, have recently become generalized in the therapeutic arsenal of many medical specialities; they are giving rise to phenomena of abuse, dependence and diversion towards the illicit market. Demands for detoxification treatment, their mixture with illegal substances, and cases of death should alert us to the abuse of these medicines.

An increase in the consumption of vegetable substances with a hallucinogenic effect has been observed. Some of these substances are associated with ancestral religious ceremonies, while many of them are legal or are partially regulated. Salvia divinorum is a powerful kappa receptor agonist, with dissociative and hallucinogenic properties, which start quickly and have a short duration. Kratom (Mytragyna speciosa) has mitragynine as its principal alkaloid, with stimulating effects at low doses (coke-like effect), and sedative effects (opiate-like effect) at high doses. Several deaths from its consumption have been detected. The consumption of hallucinogenic mushrooms appears in cyclic form, although there has been increase in their online offer. They are consumed in search of their hallucinogenic effects, above all those belonging to the family of psilocybes, which contain tryptamines with a hallucinogenic effect similar to LSD. Peyote (Lophophora psilocybes), a cactus rich in mescaline (trimetoxifeniletilamina), produces hallucinations of the five senses, and forms part of the religious culture of the North American Indians. Daturas, which are ubiquitous, produce anticholinergic symptoms and effects on the central nervous system (delirium, hallucinations, etc.), due to their high atropine and scopolamine content. Other substances used for their hallucinogenic effects include the drink known as ayahuasca, and seeds for preparing infusions like Ololiuqui, Morning Glory (Ipomoea violacea), Hawaian Baby Woodrose (Argyreia nervosa), Syrian Rue (Peganum harmala) and Iboga Rootbark (Tabernanthe iboga)

Buprenorphine is a partial mu-opioid receptor agonist that is approved for the treatment of opioid dependency. It is generally believed to be safer than methadone because of its ceiling effect on respiratory depression. As more adults in US households use buprenorphine, an increasing number of children are being exposed. We report a fatal exposure to buprenorphine in a small child that occurred after ingestion of a caretaker's buprenorphine/naloxone. Postmortem toxicology analysis showed free serum concentrations of 52 ng/mL and 39 ng/mL for buprenorphine and norbuprenorphine, respectively. No other drugs were detected. Autopsy did not find signs of injury or trauma. The theoretical safety provided by the ceiling effect in respiratory depression from buprenorphine may not apply to children, and buprenorphine may cause dose-dependent respiratory depression.

Objective. Dabigatran is a direct thrombin inhibitor approved for anticoagulation in non-valvular atrial fibrillation and, in some countries, for thromboembolism prophylaxis following select orthopedic surgeries. Despite decreased rates of thromboembolism, bleeding remains a risk due to the inability to conveniently monitor anticoagulant effect and the lack of a reversal agent. Case series. We present four cases of dabigatran-related bleeding. A 79-year-old man on aspirin, clopidogrel, and dabigatran presented with rectal bleeding and epistaxis. He died despite transfusion and administration of prothrombin complex concentrate. A 73-year-old woman on dabigatran and aspirin survived after transfusion and an emergent sternotomy for cardiac tamponade. An 86 year-old man with kidney disease and thrombocytopenia received packed red blood cells, platelets, and fresh frozen plasma for rectal bleeding while on dabigatran. An 80 year-old man on dabigatran had a subdural hematoma after falling and hitting his head. Serial imaging showed no progression. Conclusion. The absence of a reversal agent for dabigatran raises concern for uncontrollable bleeding and death. Dabigatran's listed contraindications include active bleeding and a history of dabigatran hypersensitivity reaction. Wider use may result in bleeding rates higher than anticipated from clinical trials. Risks factors that may have contributed to bleeding in these patients include concomitant bleeding diathesis, antiplatelet agent use, renal insufficiency, advanced age, and fall risks.

BACKGROUND: The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatment (ECTR) in poisoning. To test and validate its methods, the workgroup reviewed data for thallium (Tl). METHODS: After an extensive search, the co-chairs reviewed the articles, extracted the data, summarized findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and RAND/UCLA Appropriateness Method to quantify disagreement. Blinded votes were compiled, returned, and discussed during a conference call. A second vote determined the final recommendations. RESULTS: Forty-five articles met inclusion criteria. Only case reports and case series were identified, yielding a very low quality of evidence for all recommendations. Data on 74 patients, including 11 who died, were abstracted. The workgroup concluded that Tl is slightly dialyzable and made the following recommendations: ECTR is recommended in severe Tl poisoning (1D). ECTR is indicated if Tl exposure is highly suspected on the basis of history or clinical features (2D) or if the serum Tl concentration is >1.0 mg/L (2D). ECTR should be initiated as soon as possible, ideally within 24-48 hours of Tl exposure (1D), and be continued until the serum Tl concentration is <0.1 mg/L for a minimal duration of 72 hours (2D). CONCLUSION: Despite Tl's low dialyzability and the limited evidence, the workgroup strongly recommended extracorporeal removal in the case of severe Tl poisoning.