2/16/2014 The unstable overdose patient The unstable overdose - PDF document

2/16/2014 The unstable overdose patient The unstable overdose patient Craig Smollin MD Associate Medical Director California Poison Control Center, SF Division Rob Ford - Mayor of Toronto Objective • Discuss clinical scenarios unique to the acutely poisoned unstable QuickTime™ and a decompressor are needed to see this picture. patients and representing high risk situations. 1

2/16/2014 Remember Poison control center data 2011 What are the most common interventions performed in acute poisoning? Reminder Clinical Scenarios • Aspirin overdose - Issues concerning airway • A case of severe acidosis • Poisoned patient need really good supportive care ! • Cardiotoxicity - How is this shock different? • Drug induced seizures 2

2/16/2014 Unstable overdose case #1 Unstable overdose case #1 • A 58 year-old male presents after • Initial treatment should include which of the ingesting an unknown quantity of aspirin in a suicide attempt. The patient following? appears diaphoretic and tachypneic, with • a. Intravenous fluids a respiratory rate of 32. Lungs are clear to auscultation bilateral. • b. Bicarbonate drip • Initial aspirin level = 110 mg/dL • c. Potassium supplementation • pH = 7.5, pCO2 = 17 mmHg, HCO3 = 13 • d. Nephrology consultation mmol/L • e. All of the above Unstable overdose case #1 • Initial treatment should include which of the following? • a. Intravenous fluids • b. Bicarbonate drip • c. Potassium supplementation • d. Nephrology consultation http://www.acmt.net/ • e. All of the above 3

2/16/2014 Unstable overdose case #1 • Intravenous fluids - hypovolemia often not addressed • Bicarbonate drip - enhanced elimination Unstable overdose case #1 Unstable overdose case #1 • Indications for dialysis: • Intravenous fluids - hypovolemia often not addressed • Rising levels • Bicarbonate drip - enhanced elimination • AMS, cerebral edema, seizures • K+ supplementation - hypokalemia works against you • Pulmonary edema • Nephrology consultation - aspirin can be dialyzed • Renal insufficiency • Deteriorating clinical condition • Profound acidemia 4

2/16/2014 What about intubation? What about intubation? • A 58 year-old male presents after • A 58 year-old male presents after ingesting an unknown quantity of aspirin ingesting an unknown quantity of aspirin in a suicide attempt. The patient in a suicide attempt. The patient appears diaphoretic and tachypneic, with appears diaphoretic and tachypneic, with a respiratory rate of 32. Lungs are clear a respiratory rate of 32. Lungs are clear to auscultation bilateral. to auscultation bilateral. • Initial aspirin level = 110 mg/dL • Initial aspirin level = 110 mg/dL • pH = 7.5, pCO2 = 17 mmHg, HCO3 = 13 • pH = 7.5, pCO2 = 17 mmHg, HCO3 = 13 mmol/L mmol/L Unstable overdose case #1 Unstable overdose case #1 • The treating physician is concerned that the patient • The patient died 40 minutes post is tiring and elects for rapid sequence intubation with etomidate and succinylcholine. intubation. • Post intubation ABG Think twice about intubating the aspirin poisoned patient ! • pH = 7.04, pCO2 55 mmHg, HCO3 = 9 mmol/L. (pH = 7.5, pCO2 = 17 mmHg, HCO3 = 13 mmol/L) 5

2/16/2014 Mechanical ventilation in aspirin poisoning Mechanical ventilation in aspirin poisoning • Case series of 7 patients with salicylate poisoning • Individual case reports of hypoventilation in (asa level > 50mg/dL) who underwent mechanical ventilation salicylate poisoned patient resulting in death: • • post-MV pH in all patients was <7.4 Salicylate-Associated Asystole: Report of Two Cases Am • J Med 1989;86: 505-6 In 5 patients post-MV pCO2 was > 50 mmHg • • Deleterious effects of endotracheal intubation in 2/7 died post intubation (within hours) salicylate poisoning Ann Emerg Med 2003; 41:583-4 • One patient with severe neurologic injury Stolbach et. al. Mechanical ventilation was associated with acidemia in a case series of salicylate-poisoned patients. Acad Emer Med 2008 Sep;15(9): 866-9 Expert Opinion Expert Opinion • Hyperventilation is not itself an indication for • Coingestion or therapeutic administration of intubation • Intubation and mechanical ventilation can be CNS/respiratory depressant drugs may also precipitate clinical deterioration associated with rapid worsening of toxicity and • Alcohol increased mortality. • • Maintain alkalosis through hyperventilation and Opiates • intravenous sodium bicarbonate. Benzodiazepines • Once intubated, maintain minute ventilation and low • Antihistamines pCO2. American College of Medical Toxicology (ACMT) Guidance Document: American College of Medical Toxicology (ACMT) Guidance Document: Management Priorities in Salicylate Toxicity http://www.acmt.net accessed Management Priorities in Salicylate Toxicity http://www.acmt.net accessed 1/2014 1/2014 6

2/16/2014 When is intubation indicated? Unstable overdose case #2 • A 25 year-old female with no sig PMH suddenly collapsed while at work. Upon arrival to the • Altered mental status emergency department she was unresponsive with a GCS of 5. • Pulmonary edema • BP is 90/p, HR 110 bpm, O2 Sat • Hypoventilation 100%, T afebrile. • Pupils 4 mm, sluggishly reactive, • Aspiration risk lungs sounds clear, neuro exam restless, nonpurposful movements. Unstable overdose case #2 Unstable overdose case #2 • A 25 year-old female with no sig PMH suddenly collapsed while at work. Upon arrival to the emergency department she was unresponsive with a GCS of 5. • Blood glucose = 158 mg/dL • BP is 90/p, HR 110 bpm, O2 Sat • ABG: pH 7.01, pCO2 = 21 mmHg HCO3 = 8 mmol/L 100%, T afebrile. • Pupils 4 mm, sluggishly reactive, lungs sounds clear, neuro exam restless, nonpurposful movements. 7

2/16/2014 Unstable overdose case #2 Unstable overdose case #2 • Blood glucose = 158 mg/dL • ABG: pH 7.01, pCO2 = 21 mmHg HCO3 = 8 mmol/L Call poison control ! 25 year old female with sudden collapse? Did you call poison control ! Call poison control 1-800-222-1222 ! Call them already ! 8

2/16/2014 Unstable overdose case #2 Unstable overdose case #2 • Additional laboratory studies: • Tylenol, aspirin, ethanol levels negative • Initial treatment includes the following: • WBC 19K • • Intubation Na 142, K 4.3, Cl 101, HCO3 9, BUN 8, Cr 1.5, Glucose • 155 IV fluids • Anion gap 22 • Additional laboratory studies • Serum ketones negative • STAT head CT negative • Lactate 10 mmol/L Clinical clues to the diagnosis Unstable overdose case #2 • Additional laboratory studies: Sudden collapse • Tylenol, aspirin, ethanol levels negative • Severe acidosis WBC 19K • Elevated anion gap Na 142, K 4.3, Cl 101, HCO3 9, BUN 8, Cr 1.5, Glucose 155 • Elevated lactate Anion gap 22 • No ketones Serum ketones negative • Lactate 10 mmol/L 9

2/16/2014 Unstable overdose case #2 Selected drugs and toxins causing lactic acidosis Acetaminophen Metformin Antiretroviral drugs • Additional history Propofol Beta agonists Salicylates • Caffeine Works in a laboratory with access to chemicals Seizures, shock, hypoxia Carbon Monoxide • Sodium azide Cyanide Has access to potassium cyanide Theophyilline • Hydrogen sulfide Co-oximetry reveals no evidence of CO Iron Isoniazid Electron Transport Chain Cyanide: Pathophysiology Mitochondrial Matrix 10

2/16/2014 Electron Transport Chain Electron Transport Chain e - e - H+ H+ H+ NADH NADH Electron Transport Chain Electron Transport Chain H+ H+ H+ e- ADP H+ ATP NADH NADH H+ H+ 11

2/16/2014 Electron Transport Chain Electron Transport Chain cytochrome aa3 cytochrome aa3 CN CN ADP ADP ATP ATP NADH NADH Treatment of CN Poisoning • Removal from source • 100% oxygen by tight-fitting mask/ET tube • Cyanide antidote kit? • Hydroxocobalamin? hydroxoCob Vit B12 12

2/16/2014 Cyanide Antidote Kit Shuttle Dumps Chelates hydroxoCob Vit B12 Nitrites Nitrites 13

2/16/2014 Nitrites Sodium thiosulfate Sodium thiosulfate Hydroxocobolamin • Combines with CN to form Vitamin B12. • Appears to be effective and safe • Preferred drug for CN due to smoke inhalation (safer than nitrites) 14

2/16/2014 Hydroxocobolamin • Side effects: – Red Skin, secretions 2-7 days – Nausea, vomiting – Occasional HTN and muscle twitching from Clin Toxicol 2006; 14.17 57 Unstable overdose case #3 Unstable overdose case #3 • A 45 year-old female with a history of • A 45 year-old female with a history of depression presents 1 hour after a depression presents 1 hour after a large ingestion of her antihypertensive large ingestion of her antihypertensive medications. On arrival she is medications. On arrival she is somnolent but arousable and has a somnolent but arousable and has a GCS of 14. GCS of 14. • Vital signs: BP 83/50, HR 65, RR 18, • Vital signs: BP 83/50, HR 65, RR 18, O2 sat 98% RA O2 sat 98% RA • Calcium Channel Blockers Finger stick glucose = 235 • Finger stick glucose = 235 • Beta Blocker Venous lactate = 5 mmol/L • Digoxin Venous lactate = 5 mmol/L • Clonidine rr Hyperkalemia 15