Toxidromes

Question 1

Toxidromes

Hydrogen Sulfide (H2S) gas exposure locations:

Answer 1

Sewers, wells, volcanoes, hot springs, oil and gas industry, fracking

Question 2

Toxidromes

Hydrogen Sulfide (H2S) gas exposure symptoms:

Answer 2

HA, N/V, cough, confusion, LOC, upper airway irritation, conjunctivitis, seizure, cardiac arrest, MI, knock down effect (sudden loss of consciousness)

Question 3

Toxidromes

Hydrogen Sulfide (H2S) gas workup labs:

Answer 3

VBG, CXR, ECG, CBC, BMP, co-oximetry

Question 4

Toxidromes

Hydrogen Sulfide (H2S) gas workup treatment:

Answer 4

Tx: remove from environment, 100% FiO2, ± ETT/RSI prn, ± pressors for ↓BP, sodium nitrite 10 ml of 3% sol over 2 min to induce methemoglobinemia, ± HBO
Sodium nitrite can cause hypotension
Can consider cobinamide, hydroxocobalamin and methylene blue

Question 5

Toxidromes

Hydrofluoric acid exposures?

Answer 5

Jewelers, petrochem, rust removal, glass etching solutions

Question 6

Toxidromes

Hydrofluoric acid symptoms?

Answer 6

Sx:
Dermal - liquefactive necrosis, pain-out-of-proportion
Inhalation - pulm edema/ARDS, cough, wheeze
Ingestion - N/V, abd pain, viscus perforation
Systemic - ↓ Ca, ↓ Mg, ↑ K, VF/torsades and metabolic acidosis

Question 7

Toxidromes

Hydrofloric acid treatment?

Answer 7

Tx:
Remove clothes and irrigate copiously, ECG (QT, hypocalcemia), electrolytes
Ca gluconate gel (NOT Ca Chloride) AAA and/or Ca gluc sol SQ for skin burn, Ca gluc neb for inhalation,
Electrolyte replacement (will need CVL and CaCL plus Mg)
Ventricular dysrhythmias/arrest: ACLS, intubation, calcium gluconate or chloride 1v q 5 min unil ROSC, sodium bicarb, magnesium

Question 8

Toxidromes

INH Pathophysiology?

Answer 8

Prevents conversion of pyridoxine → pyridoxine-5-phosphate. Needed cofactor for glutamic acid → GABA
Deficiency of GABA→ seizures

Question 9

Toxidromes

INH Toxic dose?

Answer 9

> 3 grams causes rapid onset of toxicity within 30 minutes
Peak absorption 1-2 hours, metabolized by liver

Question 10

Toxidromes

INH Treatment?

Answer 10

Tx: Pyridoxine/B6 4 gm IV

Question 11

Toxidromes

Digitalis Types and causes?

Answer 11

acute vs. chronic (foxglove, oleander)

Question 12

Toxidromes

Digitalis Acute Toxcicity?

Answer 12

Acute: 10 x daily dose, dose ingested > 10 mg (adult) or > 4 mg (child), serum digoxin > 15, serum K > 5.5

Question 13

Toxidromes

Digitalis Symptoms?

Answer 13

Sx: yellow-green vision, fatigue, N/V/D, palpitations, syncope, AMS, arrhythmias

Question 14

Toxidromes

Digitalis Treatment?

Answer 14

Tx: Digibind 10 vials IV for ave adult, 20 vials in cardiac arrest, chronic 4-6 (indications Malignant dysrhythmia, K>5, Dig level >15 acutely or >10 6 hours post
ingestion)
Cardiac arrest- 20 vivals, should continue for at least 30 minutes after
If unable to get digibind: AV atropine, Ventricular tachydysrhythmia- lidocaine
Hyperkalemia: treat as normal
Stone heart: historical thought that calcium was cause stone heart. If undifferentiated hyperkalemia should give Ca. If known acute dig OD don’t need to give
Ca because already intracellularly loaded with calcium.

Question 15

Toxidromes

Methemoglobinemia Causes?

Answer 15

Nitrites, nitrates, dapsone, phenazopyridine, benzocaine

Question 16

Toxidromes

Methemoglobinemia Diagnosis?

Answer 16

Need co-oximetry analysis, pulse ox reads 85%

Question 17

Toxidromes

Methemoglobinemia Treatment?

Answer 17

Tx: Methylene blue 1-2 mg/kg IV of 1% sol, if doesn’t improve consider sulfa-Hb

Question 18

Toxidromes

What medications can cause NMS?

Answer 18

Phenothiazines, butyrophenones, thioxanthenes, benzamides, clozapine, risperidone, abrupt stopping of neuroleptic, alcoholics, exhaustion, dehydration

Question 19

Toxidromes

What are the signs and symptoms of NMS?

Answer 19

Develops over 24-72 hours, hyperthermia, rigidity, rhabdomyolysis
Decreased chest wall compliance tachypnea, dyskinesia, agitation, coma, chorea, trismus, renal failure, autonomic dysfunction, increased LFTs

Question 20

Toxidromes

How is NMS different from Serotonin Syndrome?

Answer 20

Differences from SS: prolonged exposure to neuroleptics or after withdrawal of dopamine receptor agonist, develops over days to weeks, hyperthermia,
severe muscle rigidity, rhabdomyolysis, associated with multiorgan failure

Question 21

Toxidromes

What is the treatment for NMS?

Answer 21

Supportive, hyperventilation, fluid resuscitation, cool, paralyse
Bromocriptine, amantadine, dantrolene

Question 22

Toxidromes

What is the pathophysology of Serotonin Syndrome?

Answer 22

SS: drug induced over stimulation of serotonin receptors in CNS → CNS dysfunction, autonomic dysfunction and neuromuscular effects
2 or more serotonergic drugs (SSRIs, TCAs, MAO-1, St Johns Wort, methylene blue) (venlafaxine highest mortality)

Question 23

Toxidromes

How quickly does Serotonin Syndrome onset?

Answer 23

Onset within 24 hours

Question 24

Toxidromes

What are the signs and symptoms of Serotonin Syndrome?

Answer 24

Tachycardia, BP changes, flushing, tachypnea, confusion, seizures, coma, agitation, restless, clonus, hyperreflexia, ataxia, rigidity, dilated pupils, fevers,
DIC, renal failure

Question 25

Toxidromes

What is the treatment for Serotonin Syndrome?

Answer 25

Tx: supportive, benzodiazepine (seizures), if marked hyperthermia, rhabdomyolysis, DIC, renal failure, ARDS → cyproheptadine and chlorpromazine
Can try AC if ingested within 1 hour

Question 26

Toxidromes

Malignant Hyperthmia Signs and Symptoms?

Answer 26

Increased ETCO2, tachycardia, tachypnea, masseter spasm, muscle rigidity, temperature increase, difficult to ventilate, HTN, sweating, DIC, hyperkalemia

Question 27

Toxidromes

Malignant Hyperthmia Treatment?

Answer 27

Tx: Stop anesthetic agents, maintain anesthesia with other agents, muscle relaxation, hyperventilation, 100% O2, cool, mainatin UO, inotrops prn, bicarb prn
Hyperkalemia treatments, BB and lidocaine for arrhythmias, monitor for DIC
Dantrolene 2.5 mg/kg q 5 min