Overdose Emergencies

Drug overdose has been a huge topic in Canada recently. Opioid painkiller addiction and fentanyl use have constantly been on TV, either as incidents leading to news reports or documentary/journalism pieces bringing about awareness. Not to mention tabloids blasting the alleged details of various actors’ drug rehab fails. So the issue of drug overdose is really not a new one. Below are some general guidelines to follow.

If the patient is alert enough, try to take as much history as possible: which substance did they use? How much did they use? Via what route? How much time has passed since usage? It’s also important to document the factors that can determine outcome, such as age, weight, underlying medical problems, and other medications. Remember to ask about suicide ideation and intention.

Always suspect overdose when:

·      Altered level of consciousness/coma

·      Young patient with life-threatening dysrhythmia

·      Trauma patient

·      Bizarre or puzzling clinical presentation

Manage DRABC first. DRAB is the same as conventional protocol, but D can be split into three different meanings: drugs, draw bloods, and decontamination (decrease absorption or increase elimination). E stands for examine the patient and exposure to specific toxidromes. F stands for full vitals monitoring (e.g. ECG, urinary catheter, X-rays); conduct physical examination with emphasis on vital signs, GCS, and pupils. The definitive treatment depends on what the patient has overdosed on.

Universal antidotes (remember DON’T):

D—dextrose

O—oxygen

N—naloxone

T—Thiamine (must give this BEFORE dextrose)

Naloxone administration may cause opioid withdraw in chronic users. Mild symptoms of opioid withdraw may include lacrimation, rhinorrhea, diaphoresis,

yawning, piloerection, hypertension, and tachycardia. Severe withdraw symptoms include hot and cold flushes, arthralgia, myalgia, abdominal cramping, and nausea and vomiting.

Blood work should include:

·      General: CBC, BUN/creatinine, glucose, INR/PTT, osmolality

·      ABG and oxygen saturation

·      Protein and albumin

·      Lactate

·      Ketones

·      Liver enzymes

·      Creatine kinase

·      Electrolytes and especially the following

o   Calcium

o   Magnesium

o   Phosphophate

·      Drug levels (can guess based on history and clinical findings)

o   Acetylsalicylic acid (ASA)

o   Acetaminophen

o   Ethanol

o   Urine screens also available

o   Remember negative toxicology screen does not rule out a toxic ingestion

Decontamination and enhanced elimination really depends on the area affected. For ocular, use saline irrigation to neutralize pH; alkali exposure requires ophthalmology consult. Dermal decontamination requires the removal of patient’s clothing (wear protective gear!), brush off toxic agents, and irrigate all external surfaces. For gastrointestinal decontamination, a single dose of activated charcoal can be given; beware that lithium, iron, alcohols, lead, and caustics are NOT absorbed by activated charcoal. Slow whole bowel irrigation (500ml in adults and slowly increase rate hourly) can be carried out.

Hemodialysis is use for the ingestion of methanol, ethylene glycol, salicylates, lithium, phenobarbital, chloral hydrate, theophylline, carbamazepine, valproate, and methotrexate. It can also be used in those who have impairment in normal mode of elimination.

Physical examination:

·      Vital signs (including temperature)

·      Skin (needle tracks, color) and mucous membranes

·      CNS, pupils

·      Odor

·      Head-to-toe survey

o   C spine

o   Signs of trauma, seizures (incontinence, tongue-biting), infection (meningismus), chronic alcohol/drug abuse (track marks, nasal septum erosion)

·      Mental status

Below is a guide to differential diagnosis based on clinical laboratory findings. It’s good to know, but I don’t think it’s absolutely necessary to commit to memory.

Below are two tables showing some toxidromes. I think it’s useful as a reference, but once again I don’t think it’s necessary to commit to memory because it’s just far too much and too complex.

Definitive treatment involves giving specific antidotes and treatments.

Substance	Antidote
Acetaminophen	N-acetylcysteine
Anticholinergics	Physostigmine
Benzodiazepines	Flumazenil
Calcium channel blockers	Calcium chloride, calcium gluconate
Cyanide or nitrate	Methylene blue
Digoxin	Digoxin immune fab
Heparin	Protamine sulfate
Iron	Deferoxamine
Insulin	Glucagon
Lead	Succimer
Opioids	Naloxone or nalmefene
Warfarin	Vitamin K

Warfarin overdose treatment is dependent on the INR of the patient.

<5.0                Hold warfarin, observation, and serial INR/PT

5.1~9.0          If no risk of bleeding, hold warfarin for 1~2 days and reduce maintenance dose. If risk of bleeding, vitamin K 1~2mg PO.

9.1~20.0        Hold warfarin, vitamin K 2~4mg PO, serial INR/PT, additional vitamin K if necessary

>20.0              Hold warfarin, vitamin K 10mg IV over 10min, increase dosing every 4 hours if needed

Lastly, here are some extra random bits of information that may prove to be useful—but I don’t think it’s necessary to commit this to memory.

As usual, you are most welcome to contribute further by posting on comment section below. Any suggestions for future episodes are also welcome. 

This blog post is available in podcast form! Look for "Med On The Go" on iTunes, Google Play, and Podbean or at www.medonthego.podbean.com.

Alcohol-related Emergencies

Be it a pint of cold beer on hot summer’s day or a glass of peppery shiraz after a day of hard work—my preferred poison is alcohol! So of course I’m going to hate covering this topic!

Alcohol intoxication

·      Slurred speech, disinhibition, lack of coordination, CNS depression

·      Hypotension (peripheral vasodilation)

·      Nystagmus, diplopia, dysarthria, ataxia, sometimes can progress to coma

·      If obtunded, need to rule out

o   head trauma/intracranial hemorrhage

o   Other drugs

o   Hypoglycemia

o   Hepatic encephalopathy: confusion, altered LOC, coma

o   Wernicke’s encephalopathy: ataxia, ophthalmoplegia, delirium

o   Postictal state

o   Basilar stroke

Complications of alcohol intoxication:

·      Cardiovascular

o   Hypertension

o   Cardiomyopathy: SOB, edema

o   Dysrhythmia “holiday heart”

§  Atrial fibrillation most common

§  Atrial flutter

§  SVT and VT (especially Torsade’s if hypomagnesemic or hypokalemic)

·      Metabolic

o   Alcoholic ketoacidosis

§  History of chronic alcohol intake and abrupt cessation/decrease

§  Malnutrition

§  Abdominal pain with nausea and vomiting

§  Classic combo: metabolic acidosis with big anion gap, urine ketones, low glucose, and normal osmolality

§  Treatment: thiamine 100mg IM/IV, dextrose, volume replenishment with normal saline

§  Usually resolves in 12~24 hours

o   Ingestion of other alcohols—produces severe metabolic acidosis with anion gap while ethanol co-ingestion has a protective effect

§  Ethylene glycol

·      CNS, CVS, renal abnormalities

§  Methanol

·      Early: lethargy, confusion

·      Late: headache, visual disturbances, nausea and vomiting, abdominal pain, tachypnea

§  Treatment

·      Urgent hemodialysis

·      Fomepizole IV bolus OR ethanol 10% IV bolus and infusion

·      Reduce active metabolites by giving folic acid for methanol ingestion and pyridoxine and thiamine for ethylene glycol ingestion

o   Other abnormalities associated with alcohol (CKPMS)

§  Hypocalcaemia (C)

§  Hypokalemia (K)

§  Hypophosphatemia (P)

§  Hypomagnesaemia (M)

§  Hypoglycemia (S)

·      Gastrointestinal

o   GI bleeds

o   Gastritis

o   Pancreatitis

o   Hepatitis

o   Spontaneous bacterial peritonitis

Beware of alcohol withdrawal!

Time since last drink	Syndrome	Description
6~8 hours	Mild withdrawal	Generalized tremor, anxiety, agitation, no delirium, autonomic hyperactivity such as sinus tachycardia, insomnia, nausea, vomiting
1~2 days	Alcoholic hallucinations	Visual (most common), auditory, and tactile hallucinations Vitals often normal
8 hours ~ 2 days	Withdrawal seizures	Typically brief generalized tonic-clonic seizures that may occur in clusters within a few hours CT head if focal seizures have occurred
2~5 days	Delirium tremens	Occurs in 5% of untreated withdrawal patients and has a high mortality rate Severely confused state, fluctuating LOC, agitation, insomnia, hallucinations/delusions, tremor, tachycardia, fever, diaphoresis

Treatment:

·      Diazepam or lorazepam IV/PO every hour until calm

·      Frequency of dosages vary depending clinical response

·      Thiamine IM/IV

·      If hypomagnesemic, give magnesium sulfate IV over 1~2 hours

·      Admit patients with delirium tremens or multiple seizures

Before letting the patient leave the ER ensure that his vital signs are stable and that he is fully oriented and can walk unassisted. Social service referral can be made to help seek shelter or detox program. Ensure the patient can obtain any medications prescribed and complete any necessary followup.

As usual, this post is available in podcast form. Look for "Med On The Go" on iTunes, Google Play, and Podbean www.medonthego.podbean.com