MCCQE 1 Exam 2023 Questions with correct Answers

HERPETIC WHITLOW - Answer- Painful grouped vesicles on an erythematous base located on the distal finger Cause: Infection with HSV Treatment: Self-limiting disease Antiviral (e.g., acyclovir) may be beneficial ONYCHOCRYPTOSIS/ INGROWN NAILS - Answer- Inflammation and soft tissue hypertrophy +/− secondary infection occurring when the lateral edge of the nail plate impinges on the nail fold ONYCHOCRYPTOSIS Cause: Onychomycosis Incorrect technique of nail cutting Repetitive trauma Poor foot hygiene; poorly fitting shoes - Answer- Treatment Barrier placement between nail plate and nail fold Excision of the portion of nail plate pressing on the nail fold +/− Antibiotics Biphasic Anaphylaxis - Answer- Recurrence of Sx 4 to 32 h (mean 10 h) after the initial episode. Occurs in up to 20% of patients and is due to the release of 2◦ mediators and the late-phase response. Protracted Anaphylaxis - Answer- Refractory Resp distress or hypotension despite appropriate medical Rx. What Saves Lives? EPI, EPI, EPI - Answer- Adults: 0.3 to 0.5 mg IM Children: 0.01 mg/kg IM I V EPI: 0.1 mg, dilute 0.1 mL 1:1,000 in 10 mL N/S Give 1 to 2 mL/min All patients presenting with signs or Sx of anaphylaxis get: - Answer- • Measures to stop any continuing Ag exposure • Two large bore I Vs • Supplemental O2 • Cardiac and O2 sat monitoring • EPI IM or I V • Methylprednisolone 125 mg I V • Diphenhydramine 50 mg I V + ranitidine 50 mg I V MINOR BURNS - Answer- • cleaning with soap and water or dilute antiseptic solution. Td immunization prn topical Abx: 1%silver sulfadiazine(Dermazine) , bacitracin (Baciguent), or bacitracin/neomycin/polymyxin B (Neosporin ointment). Occlusive, clean dressings should be applied regularly. Parkland Formula - Answer- Fluid required (ml of RL) = 4 × kg body wt × TBSA • 1/2 given in first 8 h from time of injury, 1/2 given in next 16 h Anticholinergic - Answer- Antihistamines, TCAs, phenothiazines, atropine Cholinergic - Answer- Insecticides, nerve agents, nicotine, pilocarpine, urecholine Sympathomimetic - Answer- Cocaine, amphetamines, MDMA (ecstasy), ephedrine, theophylline Opiate/sedative - Answer- Heroin, morphine, benzodiazepines, barbiturates, meprobamate, EtOH Hallucinogens - Answer- LSD, mescaline, phencyclidine, psilocybin CVS - Answer- β-Blockers, CCBs Serotonin - Answer- MAOI, SSRI, meperidine, TCA, L-tryptophan Cellular - Answer- CO, H2S, cyanide TCAs - Answer- Amitriptyline, doxepin Simple asphyxiants - Answer- CO2, inert gases Drugs inducing metabolic acidosis (BP usually low) - Answer- Ethanol, methanol, ethylene glycol, ASA, NSAID, tylenol Anticholinergic ''hot as a hare, dry as a bone, red as a beet, blind as a bat, and mad as a hatter'' • ↑ Temperature • Possible ↑ HR • Dry mucous membranes • Erythematous • Mydriasis • Disoriented, agitated - Answer- • Reaching blindly for objects • Large ODs can lead to depressive state (sedation, coma) • ↓ bs and ↓ GI motility • Urinary retention Sympathomimetic ''fight or flight'' • ↑ HR • ↑ BP • ↑ Temperature - Answer- • Wet mucous membranes • Diaphoretic • Erythematous • ↑ Psychomotor activity • Mydriasis • Agitated, ' reved up'' Serotonin ''wet dog shakes'' • ↑ Temperature • Whole body tremor • May be diaphoretic; shivering; fever; diarrhea - Answer- • Altered or normal mental status • ↑ Reflexes • ↑ Tone Cholinergic ''secreting from every orifice''/ ''wet from head to toe'' • ↓ HR • May see ↓ BP • May see ↓ RR and Resp failure • Diaphoretic• Lacrimation• Salivation - Answer- • Fasciculations • Miosis common, may see mydriasis • Altered or normal mental status • Nausea + vomiting • Defecation • Urination • Bronchorrhea Opiod or sedative/hyponotics ''depressed all over'' - Answer- • ↓ RR• ↓ HR• ↓ BP • ↓ Temperature • Range from stuporous/drunk to coma • Miosis, possible nystagmus • ↓ LOC POISON labs: • Routine: CBC, Lytes, gluc., ASA + acetaminophen + EtOH levels, blood gas, serum Osm, ECG - Answer- • Additional tests to consider: INR/PT, LFTs, RFTs, specific drug levels, β-HCG if fertile female, urine tox screen (often unhelpful from a Tx perspective, but can identify other drug exposures) Consider AXR indications = ''CHIPES'') - Answer- ''CHIPES'' Calcium, Chloral hydrate, CCl4 Heavy metals Iron Potassium Enteric-coated Salicylates Elevated AG Acidosis ''MUDPILES'' - Answer- Methanol Uremia Diabetic ketoacidosis/alcoholic ketoacidosis Paraldehyde Isoniazid, iron Lactate Ethylene glycol Salicylates Normal AG Acidosis ''HYPERCHLOREMIC'' - Answer- Usually due to ++ saline administration because of high Cl content Narrow AG ''HARDUPS'' - Answer- Hyperventilation Acetazolamide, acids, Addison disease Renal tubular acidosis Diarrhea Ureterosigmoidostomy Pancreatic fistula Saline Gastric Decontamination - Answer- General principle: ↓ absorption or ↑ excretion of ingested poisons. Generally only effective if time since exposure ≤2 h or if delayed toxicity expected. There is limited data to support most methods of gastric decontamination. Activated Carchoal may have some benefit in specific instances Enhanced Elimination - Answer- HemoDialysis or hemoperfusion as well as alkalinization of urine or diuresis are used to enhance elimination. Methanol - Answer- • Delayed presentation common (can be 6-24 h) • OG, AG may be normal or elevated • ↓ LOC, ataxia, stupor, lethargy, coma • Visual complaints common: blurry vision, ↓ acuity, ''snowstorm'' perception • CNS effects: ↓ LOC, Parkinsonism in late stages Methanol Tx - Answer- • EtOH has greater affinity for EtOH dehydrogenase and saturates it, preventing breakdown of methanol into its toxic metabolites • Fomepizole has even greater affinity and less S/Es than EtOH • NaHCO3 used for acidemia • Consider folate supplementation Methanol - Answer- Metabolism to formic acid and elimination of folate stores leads to toxicity. Metabolism occurs by EtOH dehydrogenase in the liver Salicylates - Answer- • Early: Resp alkalosis due to stimulation of CNS chemoreceptors • Late: metabolic acidosis • Severe toxic dose 300 mg/kg, toxic dose considered to be 150 mg/kg Salicylates - Answer- • Symptom onset 3-8 h after ingestion • Dehydration common • Adults: mixed acid-base with Resp alkalosis and metabolic acidosis • Children: metabolic acidosis only; indistinguishable from Reye syndrome • Salicylate levels helpful to determine severity Salicylates - Answer- • Whole Bowel Irrigation or Activated Charcoal for large ingestions; Activated Charcoal may be helpful 2 h after (''It's never to late to aspirate with salicylate'') • ++ Fluids +/− dextrose +/− K • NaHCO3 to ↓ tissue distribution and ↑ urine elimination Acetaminophen - Answer- • Metabolized almost exclusively in the liver; 5% forms toxic metabolite • Toxic metabolite is conjugated by glutathione and excreted; in OD glutathione stores are depleted and hepatocytes are susceptible to the effects of the toxic metabolite, leading to a picture of hepatotoxicity • Toxic dose reported as 150 mg/kg or 7.5 g ingested Acetaminophen • Initial Sx of anorexia, nausea+/−vomiting, and diaphoresis subside in 24-48h; patient may then become asymptomatic - Answer- • This is the ''calm before the storm'' and patients may later present as hepatic failure if ingestion is severe enough • Toxicity determined by Rumack-Matthew nomogram; must draw acetaminophen levels at 4 h postingestion and to determine probable or possible hepatic toxicity Acetaminophen Tx - Answer- • N-AcetylCysteine is specific antidote and is 100% effective in preventing toxicity if given within 8 h of severe ingestion • Liver transplantation may be only choice if hepatic failure imminent Active external rewarming technigues - Answer- • Bath immersion at 40◦C • Hot water bottles • Heating pads • Forced-air warming systems (Bair Hugger) Active internal (core) rewarming techniques - Answer- • Warmed crystalloids • Heated, humidified O2 at 41◦C • Peritoneal Dialysis • Heated irrigation (gastric, thoracic, pericardial) • Diathermy (with ultrasonic or microwaves) • Extracorporeal (venovenous, HD, continuous AV, and CPB) Ideal cooling techniques • Evaporative cooling or body cooling unit • Ice water immersion - Answer- • Ice water immersion particularly effective in hypotensive patient → promotes vasoconstriction • Specialized equipment needed (fans, water at 40◦C, etc.) • Ice water immersion may complicate resuscitation efforts Hypothermia LABWORK/INVESTIGATIONS - Answer- CBC, Lytes, gluc., INR/PTT, ABG, amylase, ECG, CXR TCAs • Tertiary amines block norepinephrine and serotonin reuptake, and their metabolites, 2◦ amines predominantly affect norepinephrine reuptake - Answer- • Also have anticholinergic and antihistaminic effects TCAs Tox • Symptom onset within 6 h • Dx made on clinical grounds; no specific levels - Answer- • May see dizziness, confusion, agitation, and variable anticholinergic effects; presentation is often nonspecific • ECG findings characteristic: may see prolonged QRS, PR, or QT +/− right axis deviation of terminal 40 mV of QRS (seen as R wave in lead aVR and S wave in lead I) TCAs Tox • Rx is supportive • Activated Charchoal if ingestion 2 h - Answer- • Benzodiazepines for seizures • NaHCO3 for ECG changes • ++Fluids+/−pressors for hypotension Heat Exhaustion - Answer- • Temperature 37.5◦C- 40.5◦C • Mental function intact • Malaise, fatigue, headache • ↑ HR, + orthostatics, clinical dehydration Heat Stroke • Temperature classically 40.5◦C • CNS dysfunction (coma, seizures, death) • Liver transaminases ↑ - Answer- • ''Classical'' heatstroke occurs usually in an elderly patient due to ↓heat dissipation • ''Exertional'' heatstroke tends to occur in younger individuals due to exercise in high ambient temperatures +/− high humidity Top Causes of Trauma Fatalities in Canada - Answer- 1. Motor Vehicle Collision 2. Falls 3. Firearms Hemorrhagic/hypovolemic shock CO↑ (↑ HR, ↑ contractility) SVR↑ (Peripheral vasoconstriction) BP Narrowed pulse pressure - Answer- BP and HR are poor indicators of hemorrhagic and distributive shock as they depend on the patient's underlying health and physiologic reserve. CO will initially ↑ but, as hemorrhage continues, the patient will eventually decompensate leading to ↓ CO and BP. Distributive shock e.g., septic, anaphylactic) - Answer- CO ↓ (↓ Preload) SVR ↓ (Peripheral vasodilation) BP Widened pulse pressure Cardiogenic shock - Answer- CO ↓ (↓ Contractility) SVR ↑ or Normal BP ↓ Obstructive shock e.g., tamponade, PE, tension pneumothorax) - Answer- CO↓ SVR↑(Primarily due to venocongestion) BP ↓ The skin is made up of four layers: - Answer- epidermis, dermis, superficial fascia, and deep fascia ''SAMPLE'' Hx: - Answer- S—Signs and symptoms of injury/illness A—Allergies M—Medications P—Past Medical History, pregnancy L—Last oral intake, including EtOH/drugs (present in 30% of cases) E—Events surrounding the accident/trauma Critical Adjuncts to Primary Survey - Answer- • Regular vitals • Pulse oximetry • ECG + telemetry • I V fluids-2 L of RL • Urinary catheter • Gastric catheter • Temperature control Trauma Lab Panel • CBC • blood Group & Screen or cross-match • INR, PTT • Lytes • BUN, Cr • β-HCG in female - Answer- Consider: • ABG • Lipase, amylase • LFTs • Drug panel trauma Diagnostic Studies - Answer- • AP CXR • AP pelvis • C-spine series • Diagnostic Peritoneal Lavage or FAST • Additional XR of suspected injuries • CT head/Abdo as appropriate POTENTIAL COMPLICATIONS OF TRAUMA TX AND RESUSCITATION • Decubitus ulcers • DVT and PE — Prophylaxis consists of daily subcutaneous enoxaparin or LMWH. • Transfusion complications - Answer- Transfusion complications: infection (HBV, bacterial pathogens); immunologic (↓ cell mediated immunity, proinflammatory effects); metabolic (hypothermia, acidosis, coagulopathy, hyperkalemia, hypocalcemia, and citrate toxicity); mistransfusion (ABO incompatibility).