Deliberate Self-poisoning with a Lethal Dose of Pentobarbital with Confirmatory Serum Drug Concentrations: Survival After Cardiac Arrest with Supportive Care.

INTRODUCTION: Pentobarbital (PB) is a euthanasia drug in doses of 2 to 10 grams, causing death within 15-30 minutes. We report a case of recovery from lethal pentobarbital deliberate self-poisoning with confirmatory serum drug concentrations. CASE REPORT: A 45-year-old male purchased 20 grams of PB powder over the Internet. He ingested this powder and then alerted his mother 10 minutes later. She found him unresponsive and commenced cardiopulmonary resuscitation (CPR). Within 20 minutes of ingestion, emergency medical services arrived and initiated advanced life support. On arrival to the emergency department, heart rate was 116 bpm, BP 117/62 mmHg, on an epinephrine infusion. He was hypotonic and hypothermic, with absent brainstem reflexes. ECG and CT brain were normal. Activated charcoal was administered and he was admitted to ICU. He remained comatose with absent brainstem reflexes until day 5. Cerebral angiogram on day 3 was normal. Qualitative urine testing detected pentobarbital suggesting ongoing drug effects as the cause of coma. He was extubated on day 10, eventually making a full recovery. At 2.5 hours post-ingestion, PB concentration was 112 mg/L; PB peaked at 116 mg/L at 29 hours; PB was 2 mg/L at 190 hours and undetectable over 200 hours post-ingestion. DISCUSSION: Average PB concentration in fatalities is reported around 30 mg/L. This patient survived higher serum concentrations with early CPR and prolonged cardiorespiratory support in the ICU. Assessment of brainstem death should be deferred until PB has been adequately eliminated.

Calcium channel antagonist and beta-blocker overdose: antidotes and adjunct therapies.

Management of cardiovascular instability resulting from calcium channel antagonist (CCB) or beta-adrenergic receptor antagonist (BB) poisoning follows similar principles. Significant myocardial depression, bradycardia and hypotension result in both cases. CCBs can also produce vasodilatory shock. Additionally, CCBs, such as verapamil and diltiazem, are commonly ingested in sustained-release formulations. This can also be the case for some BBs. Peak toxicity can be delayed by several hours. Provision of early gastrointestinal decontamination with activated charcoal and whole-bowel irrigation might mitigate this. Treatment of shock requires a multimodal approach to inotropic therapy that can be guided by echocardiographic or invasive haemodynamic assessment of myocardial function. High-dose insulin euglycaemia is commonly recommended as a first-line treatment in these poisonings, to improve myocardial contractility, and should be instituted early when myocardial dysfunction is suspected. Catecholamine infusions are complementary to this therapy for both inotropic and chronotropic support. Catecholamine vasopressors and vasopressin are used in the treatment of vasodilatory shock. Optimizing serum calcium concentration can confer some benefit to improving myocardial function and vascular tone after CCB poisoning. High-dose glucagon infusions have provided moderate chronotropic and inotropic benefits in BB poisoning. Phosphodiesterase inhibitors and levosimendan have positive inotropic effects but also produce peripheral vasodilation, which can limit blood pressure improvement. In cases of severe cardiogenic shock and/or cardiac arrest post-poisoning, extracorporeal cardiac assist devices have resulted in successful recovery. Other treatments used in refractory hypotension include intravenous lipid emulsion for lipophilic CCB and BB poisoning and methylene blue for refractory vasodilatory shock.

Management of paediatric spontaneous pneumothorax: a multicentre retrospective case series.

OBJECTIVES: Paediatric guidelines are lacking for management of spontaneous pneumothorax. Adult patient-focused guidelines (British Thoracic Society 2003 and 2010) introduced aspiration as first-line intervention for primary spontaneous pneumothorax (PSP) and small secondary spontaneous pneumothoraces (SSP). Paediatric practice is unclear, and evidence for aspiration success rates is urgently required to develop paediatric-specific recommendations. METHODS: Retrospective analysis of PSP and SSP management at nine paediatric emergency departments across Australia and New Zealand (2003-2010) to compare PSP and SSP management. RESULTS: 219 episodes of spontaneous pneumothorax occurred in 162 children (median age 15 years, 71% male); 155 PSP episodes in 120 children and 64 SSP episodes in 42 children. Intervention in PSP vs SSP episodes occurred in 55% (95% CI 47% to 62%) vs 70% (60% to 79%), p<0.05. An intercostal chest catheter (ICC) was used in 104/219 (47%) episodes. Aspiration was used in more PSP than in SSP episodes with interventions (27% (18% to 37%) vs 9% (3% to 21%), p<0.05). Aspiration success was 52% (33% to 70%) overall and not significantly different between PSP and SSP. Aspiration success was greater in small vs large pneumothoraces (80% (48% to 95%) vs 33% (14% to 61%), p=0.01). Small-bore ICCs were used in 40% of ICCs and usage increased during the study. CONCLUSIONS: In this descriptive study of pneumothorax management, PSP and SSP management did not differ and ICC insertion was the continuing preferred intervention. Overall success of aspiration was lower than reported results for adults, although success was greater for small than for large pneumothoraces. Paediatric prospective studies are urgently required to determine optimal paediatric interventional management strategies.

Comparison of size classification of primary spontaneous pneumothorax by three international guidelines: a case for international consensus?

OBJECTIVE: The aim of this study was to compare classification of pneumothoraces into size groups for treatment using the British Thoracic Society [BTS], American College of Chest Physicians [ACCP] and Belgian Society of Pulmonology [BSP] guidelines and the range of pneumothorax sizes in each group calculated using the volumetrically-derived Collins' method. METHOD: This was a retrospective cohort study. Participants were patients with primary spontaneous pneumothorax [PSP] attending emergency departments of two teaching hospitals between 1996 and 2005. Participants were identified from a pre-existing database. Data collected included demographics, side of PSP and interpleural distances for size classification based on BTS, ACCP, BSP and Collins' method requirements measured on inspiratory X-rays. The outcome of interest was comparison of classification into size groups according to each guideline. Analysis was by descriptive statistics, overall agreement and Kappa analysis for agreement between guideline pairs. RESULTS: Forty-nine episodes [44 patients] were studied. Median age was 22 years; 66% of patients were male. Median PSP size [Collins' method; inspiratory films] was 24%; range 5-100%. Based on inspiratory films, the BTS guideline classified 10% of PSP as large compared with 47% by the BSP guideline and 49% by the ACCP guideline. The three guidelines agreed in their classification in only 47% of cases. CONCLUSION: Size classification of PSP based on available treatment guideline definitions shows poor agreement. This goes some way to explain management variation between regions and limits comparability of reported outcomes. There is a strong case for international agreement in size classification/estimation in order to facilitate high-quality studies into optimal management approaches.