Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

show notes coming...

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

show notes coming...

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

show notes coming...

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

Show notes coming...

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

Show Notes Coming...

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

Show notes coming...

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

I. General Toxicology Principles

Elimination and Decontamination

Toxins that are Dialyzable: Toxins are dialyzable if they have:

• Low molecular weight.
• Low volume of distribution (low lipid binding).
• Low protein binding.
• Rapid equilibration.
• Low clearance.

Pneumonic for Dialyzable Toxins (ISTUMBLED):

• Isopropyl alcohol.
• Salicellates.
• Theophiline.
• Ureia.
• Metformin or Methanol.
• Barbbiterates.
• Lithium.
• Ethylene glycol.
• Valproic acid.

Activated Charcoal (AC) — Mainstay Decontamination

• Toxins NOT bound by AC:
• Metals (heavy metals, iron, lithium).
• Solvents.
• Caustics.
• Alcohols.
• Pesticides.

Whole Bowel Irrigation (WBI) Indications: Used for toxins that activated charcoal does not bind, or things that stick around for a long time:

• Body packers.
• Bezoars.
• Sustained release formulations.
• Metals or paint with lead.

Multi-Dose Activated Charcoal (MDAC) Indications (Pneumonic: Doubled dose activated charcoal can bind drugs quite tightly):

• Dilantin (Phenytoin).
• Digoxin
• Aspirin.
• Cyclic (TCAs).
• Carbamazepine.
• Barbbiterates.
• Dapsone.
• Quinine.
• Theophiline.

Diagnostic Gaps and Acidosis

Causes of Anion Gap Metabolic Acidosis:

• KULT mnemonic: Ketones, Uremia, Lactate, Toxins.
• A CAT MUD PILES mnemonic:
• AKA (alcoholic ketoacidosis).
• Cyanide, carbon monoxide
• Acetaminophen.
• Toluene.
• Methanol or metformin.
• Uremia.
• DKA (diabetic ketoacidosis).
• Paraldehyde.
• Isoniazid (INH) or iron.
• Lactic acid.
• Ethylene glycol.
• Salicellates (aspirin).

Toxins Causing Osmolar Gap ONLY (Initially):

• These are usually alcohols and sugars, prior to being metabolized to their toxic metabolite.
• Glycerol.
• Sorbitol.
• Acetone.
• Toxic alcohols (initially).

Differentials

Drugs that can Cause Seizures (mnemonic: Otis Campbell):

• Organophosphates or oral anti-glycemic agents.
• TCAs.
• Isoniazid (INH) or insulin.
• Sympathomimetics or salicellates.
• Cocaine, carbon monoxide, cyanate, cyanide, or chlorinated hydrocarbons.
• Amphetamines, anticholinergics, antidepressants.
• Methanol or methyl xanthines.
• PCP or propranolol (beta blocker that readily crosses the BBB).
• Benzo withdrawal or bupropion.
• Ethanol withdrawal or ethylene glycol.
• Lithium, lidocaine, lead, or lindane.

Differential for Altered Mental Status (AEIOU Tips):

• Alcohol, acidosis.
• Electrolytes or encphylopathy.
• Infection.
• Opioids or overdose.
• Uremia.
• Trauma.
• Insulin.
• Psychosis.
• Seizure or stroke.

Low and Slow Differential (BRADI):

• Brash (e.g., hyperkalemia).
• Reduced oxygen, temperature, glucose, or thyroid.
• ACS.
• Drugs (beta blockers, calcium channel blockers, clonidine, digoxin, or cholinergics).
• Infection (e.g., CNS infections or Lyme).

Anticholinergics

Anticholinergic Drugs (Pneumonic: A poop b****

• Atropine.
• Plants (gyosonweed, deadly nightshade, mandrake).
• Optho drugs (cyclopentolate).
• Oxybutynin.
• Phenytoin.
• Benztropine.
• Ipratropium.
• TCAs.
• Carbamazepine.
• H1 blockers (Benadryl or Gravol).

Anticholinergic Toxidrome:

• Dry, hot, tachycardic, crazy/delirious, mydriasis (dilated pupils).

Anticholinergic Treatment:

• Supportive care.
• Single dose activated charcoal (if seeds ingested).
• Benzos for agitation or hyperthermia.
• Cooling (mainstay).
• Physostigmine: Can be used for delirium but is strictly contraindicated if there is:
• TCA overdose.
• AV block.
• Bradycardia.
• Seizures.
• Glaucoma.

II. Specific Toxins and Overdoses

A. Tylenol (Acetaminophen - APAP)

Toxic Dosing and Levels:

• Toxic dose: Over 150 mg/kg.
• Severe massive ingestion: Over 500 mg/kg.
• Treatment line (Nomogram): Over 1,000 µmol/L at 4 hours post-ingestion.

Metabolism and Mechanism:

• Metabolized 15% via the CYP450 pathway to NAPQI (toxic metabolite).
• NAPQI causes hepatic zone 3 death.
• N-acetylcysteine (NAC) Mechanism: Increases sulfation, acts as a precursor and substitute for glutathione (which helps metabolize NAPQI), and is a free radical scavenger.

Stages/Phases of Toxicity:

1. Pre-injury (0 to 12 hours): Nausea, vomiting, malaise. High APAP level, normal AST/ALT.
2. Liver Injury (8 hours to 36 hours): Nausea, vomiting, right upper quadrant tenderness, increased AST/ALT (AST rises first).
3. Liver Failure (2 to 4 days maximum): Signs of liver failure, ARDS, sepsis, cerebral edema, hepatorenal syndrome, coagulopathy.
4. Recovery (After 4 days): Liver can completely regenerate if the patient survives.

NAC Treatment Indications (mnemonic: 1824):

• 1: Over ~1,000 µmol/L at the 4-hour mark on the nomogram.
• 8: If you Will not have an APAP level by 8 hours (start treatment within 8 hours).
• 24: Any APAP detectable after 24 hours.
• Chronic Ingestion: AST is two times normal or APAP is over 200 (consult toxicology).

NAC Dosing (21-Hour Three-Bag Protocol):

• Load: 150 mg/kg over 1 hour.
• Bag 2: 12.5 mg/kg per hour over 4 hours.
• Bag 3: 6.25 mg/kg per hour over 16 hours.

NAC Stopping Criteria:

• AST is less than 100 and downtrending.
• No detectable APAP.
• No symptoms.
• Coagulation levels are normal.

Dialysis Indications for Tylenol:

• Level over 6,620 at 4 hours.
• pH less than 7.3.
• End organ failure:
• Creatinine over 350.
• Lactate over 3.5.
• Encephalopathy.

Modified King's College Transplant Criteria:

• If after resuscitation, pH is still less than 7.3.
• OR, meeting all three of the following criteria:
• Creatinine over 291.
• INR over 6.5.
• Grade III encephalopathy (at least).

B. Aspirin (Salicylates)

Toxic Dosing and Levels:

• Therapeutic dose: 15 mg/kg.
• Toxic dose: 150 mg/kg.
• Severe dose: 500 mg/kg.
• Potentially toxic level: Over 2.2 millimoles per liter.
• Metabolism changes from first order to zero order kinetics above 2.2 millimoles per liter.

Key Mechanism (Acid-Base and pH):

• Aspirin causes respiratory alkalosis (medullary stimulation/tachypnea) and metabolic acidosis (uncoupling oxidative phosphorylation, inhibiting Kreb cycle). But also respiratory acidosis (aLOC) and metabolic alkalosis (vomiting).
• At a low pH, aspirin is unionized and crosses the blood-brain barrier.
• At a high pH, aspirin is ionized and trapped in urine/blood.

Treatment and Dosing:

• Correct dehydration and ensure potassium is over 4.5.
• Multi-dose activated charcoal every 2 to 4 hours.
• Urine Alkalinization Goals:
• Goal urine pH: 7.5 to 8.
• Max blood pH tolerated: 7.55.
• Alkalinization Recipe:
• 3 amps of bicarb into a liter of D5W.
• Run at 2 to 3 mLs/kg per hour.
• Add potassium (often 40 mEq) into the bag.
• Monitoring: Check aspirin levels every 2 hours with VBG; check urine pH hourly.

Dialysis Indications for Aspirin:

• Level over 7.2 in an acute ingestion.
• Level over 2.9 in a chronic ingestion.
• pH less than 7.2.
• End organ failure (acute renal failure, altered level of consciousness, acute lung injury, liver injury, or seizures).

Disposition:

• Check aspirin level every 2 hours until three levels are less than 2.2 (without the bicarb infusion).
• Patient must be asymptomatic and have normal pH.

C. Toxic Alcohols (Ethylene Glycol and Methanol)

General Alcohol Metabolism:

• Alcohol -> (Alcohol Dehydrogenase (ADH)) -> Aldehyde -> (Aldehyde Dehydrogenase (ALDH)->Acid.

Ethylene Glycol (EG)

• Major Toxic Metabolite: Oxalic Acid
• Worrisome Metabolite Level: Over 10 millimoles
• Treatment Level (Actual Alcohol): Over 3.23 mmol/L
• Dialysis Level (Actual Alcohol): Over 8 mmol/L
• Key Toxicity: Calcium oxalate crystals (leading to Acute Tubular Necrosis/ATN and hypocalcemia).

Methanol

• Major Toxic Metabolite: Formic Acid
• Worrisome Metabolite Level: Over 16.67 mmol/L
• Treatment Level (Actual Alcohol): Over 6.24 mmol/L
• Dialysis Level (Actual Alcohol): Over 15.6 mmol/L
• Key Toxicity: Ocular phase (snowstorm vision) and CNS symptoms (specifically putaminal necrosis).

Other Toxic Alcohols:

• Isopropyl Alcohol: Causes an osmolar gap but no anion gap. Treatment is supportive (fluids for hypotension, PPI for gastritis). Dialysis for refractory hypotension or coma.
• Diethylene Glycol: Causes lifelong renal failure. Managed like EG or Methanol.
• Propylene Glycol: Increases lactic acid. Treated with fomepizole or hemodialysis.

Treatment (EG & Methanol):

1. Decontamination: No role for GI decontamination.
2. Acidosis Correction: Correct acidosis to over 7.3 (may need bicarb).
3. ADH Inhibition (Fomepizole):
   • Fomepizole Dose: Load with 15 mg/kg, then 10 mg/kg BID.
   • Fomepizole Indications (If suspicious, treat if two of five met):
   • Acidosis less than 7.3.
   • Anion gap over 16.
   • Bicarb less than 18.
   • Osmolar gap greater than 10.
   • Urine oxalate crystals.
   • Treat immediately if: Level confirmed (Methanol > 6.24, EG > 3.23) or ingestion confirmed + osmolar gap > 10.
4. Co-Factors:
   • Ethylene Glycol: Vitamin B1 and B6.
   • Methanol: Vitamin B2.

Dialysis Indications for Toxic Alcohols:

• Specific toxic level (Methanol > 15.6, EG > 8).
• Acidosis less than 7.3.
• End organ dysfunction: Renal failure, vision loss, hyperkalemia, or hemodynamic instability.

D. Ethanol and Withdrawal

Ethanol Levels (in Millimoles):

• 5: Decreased fine motor function.
• 10: Impaired judgment (legal limit).
• 20: Gait instability.
• 30: Lethargy.
• 60: Coma.
• 80: Respiratory depression.
• Metabolism: Zero order kinetics at 5 millimoles per hour.

Wernicke's Encephalopathy:

• Triad: Ataxia, Ophthalmoplegia, Altered level of consciousness.
• Dose (Vitamin B1): 500 mg TID.

Alcohol Withdrawal Stages:

1. Autonomic Hyperactivity (0 to 24 hours): Tremor, nausea, vomiting, sweating.
2. Neuronal Excitement (1 to 2 days): Seizures, confusion.
3. Delirium Tremens (DT) (2 to 4 days): Hallucinations (lack insight), profound autonomic dysfunction, delirium.

CIWA-Ar Protocol (Scoring System Components):

• Scoring: Each mark has 0 to 7 points.
• Treatment Threshold: Over 10 points.
• Severe Withdrawal Threshold: Over 20 points.
• Components (Short NAP): Sweating, Hallucinations (tactile, visual, auditory), reduced intake, Orientation, Tremor, Nausea/Vomiting, Anxiety, Agitation, Pain (in the head).

Treatment of Severe Withdrawal (Dosing):

• Benzodiazepines (First Line): Diazepam (preferred for long half-life, 48 hours) or Lorazepam (12 hour half-life).
• Lorazepam: 1 to 4 mg IV.
• Diazepam: 5 to 10 mg IV (or PO for mild withdrawal).
• Barbiturates (Phenobarbital): Bolus 130 mg to 260 mg IV.
• Adjunctive: Thiamine (B1), Magnesium, and cooling (if hyperthermic).

Discharge Criteria:

• 6 hours post their last seizure.
• Less than two seizures total.
• Normal workup (normal head CT if seizure occurred).
• CIWA of less than 10 twice.

E. Antidepressants (TCAs and Others)

General Antidepressant Toxic Dose: 10 mg/kg.

Tricyclic Antidepressants (TCAs):

• Mechanism: Blocks norepinephrine/serotonin re-uptake, anticholinergic effect, blocks sodium/potassium channels, alpha 1 blocker (hypotension), blocks histamine/GABA receptors.
• ECG Findings:
• Tachycardic.
• QRS may be over 100 ms (considered wide).
• QTc may be greater than 500 ms.
• Terminal R wave in aVR that is more than 3 mm.
• Treatment (Dosing):
• Single dose activated charcoal.
• Sodium Bicarb: Indicated if QRS > 100, seizures, acidemia, hypotension, or dysrhythmias.
• If pH gets high (7.55), switch to 3% normal saline to aid QRS widening.
• Phenytoin or Lidocaine for dangerous arrhythmias.

Specific Antidepressants:

• Citalopram (SSRI): Higher seizure rate. Monitor for 12 hours.
• Venlafaxine (SNRI): Most worrisome SNRI due to extended release. Monitor for 24 hours.
• Bupropion (Wellbutrin):
• Overdose risk: Over 4.5 grams has a 50% risk of seizure.
• Monitoring: Definitely needs 24 hours of monitoring.

MAOIs (Tyramine Syndrome):

• Caused by eating old or fermented foods (beer, wine, aged cheese/meats) while taking MAOI.
• Symptoms: Headache, hypertension, diaphoresis.
• Treatment: Treat blood pressure (if over 200 or symptomatic) with Phentolamine or Nitroprusside.
• MAOI overdose requires monitoring for 24 hours.

F. Cardiac Toxins

Digoxin:

• Normal level: 0.9 to 1.4 nanomoles per liter (or 0.5 to 1.1 nanograms per mL).
• Arrhythmia risk: 50% will have arrhythmias at 2.5 nanograms per mL.

Digifab (Digoxin Immune Fab) Indications:

• Ventricular dysrhythmias or bradyarrhythmias affecting blood pressure.
• Potassium over 5.
• Co-ingestion with another cardiotoxic drug.
• Dose over 10 mg (adult) or 4 mg (child).
• Level over 7.68 millimoles per liter

Digifab Dosing:

• Empirical Dosing (Vials):
• Arrest: 20 vials bolus.
• Acute overdose: 10 vials.
• Chronic overdose: 6 vials.
• Stable: 1 vial.
• Calculated Dosing (Vials):
• Vials = (Dose of digoxin in mg x 0.8 [bioavailability]) / 0.5 (mg bound per vial).
• Observation: Patients need observation for at least 12 hours.

Calcium Channel Blockers (CCBs) and Beta Blockers (BBs):

• Toxic Dose: BBs (e.g., propranolol) over 1 mg/kg. Non-DHP CCBs (e.g., verapamil) 5 mg/kg.
• Dialyzable BBs (SANTA): Sotalol, Atenolol, Nadolol, Timolol, and Acebutolol.
• Monitoring: At least 6 hours (non-extended release) or 24 hours (extended release).

Treatment (High-Dose Insulin and Calcium Dosing):

• Supportive
• Calcium: 1 to 2 grams of Calcium Chloride, or triple that dose of Calcium Gluconate.
• May be followed by an infusion of 20 mg/kg per hour.
• Glucagon (if taken BBs): 10 mg IV.
• Euglycemic High-Dose Insulin (EHDI):
• Insulin run at 1 to 10 units/kg per hour.
• Run with D10 at 5 mLs/kg per hour (or as needed to maintain euglycemia).

Clonidine:

• Treatment: Fluids, pressors, and Naloxone (start at 0.1 mg, double dose as needed).
• Disposition: Monitor for 4 hours (asymptomatic) or 24 hours (symptomatic).

G. Serotonin Syndrome

Hunter Criteria (Requires Tremor or Clonus):

1. Spontaneous clonus (meets criteria alone).
2. Inducible clonus PLUS one of: agitation or diaphoresis
3. Occular clonus PLUS one of: agitation or diaphoresis,
4. Inducible OR ocular clonus PLUS hypertonia, and hyperthermia.
5. Tremors and hyperreflexia.

Treatment:

• Cooling.
• Benzodiazepines.
• Treat hypertension with Phentolamine or Nitroprusside.
• Cyproheptadine 12 mg PO (although evidence supporting benefit is noted as lacking).

H. Caustics

Types of Necrosis:

• Acids: Coagulation necrosis (painful, less penetration, leads to eschar formation).
• Alkaline agents: Liquefaction necrosis and saponification (less pain, deeper penetration).

Endoscopy Timing:

• Ideal: Delayed (after 12 to 24 hours) to better differentiate the degree of injury.
• Urgent (within 12–24 hours): If patient has vomiting, drooling, stridor, or dyspnea.

Degrees of Injury (Burn Classes/Risk of Stricture):

1. Grade 1: Edema and hyperemia (superficial injuries, no risk of strictures).
2. Grade 2: Ulcers begin to form.
   • Grade 2A (Non-circumferential): 15% risk of stricture.
   • Grade 2B (Circumferential): 75% risk of stricture.
3. Grade 3: Transmural or perforation (90% risk of stricture).

Analogy for Toxic Alcohol Management: Treating toxic alcohol overdose is like dealing with a dangerous factory that turns raw materials (EG/Methanol) into harmful pollutants (Oxalic/Formic Acid). You need to immediately hit the "stop" button on the machinery (giving Fomepizole to inhibit ADH) and then use "cleanup crew" co-factors (B vitamins) to neutralize the existing pollution, while performing "heavy industrial scrubbing" (dialysis) if the pollutant levels are already dangerously high or causing internal damage.

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

I. WOUNDS

Wound Infection Risk Based on Location

(Highest risk to Lowest risk):

1. Legs and thighs.
2. Arms.
3. Feet.
4. Chest and back.
5. Face.
6. Scalp (lowest risk due to high vascularization).

Indications for Antibiotics (CC FAM)

Antibiotics are indicated for the following types of wounds:

• Contaminated or Crush injuries.
• Cartilage injuries (e.g., nose or ears).
• Fractures (open fractures).
• Animal bites (cat, dog, human, ferret, pig, camel, bear, big cats, monkeys, etc.).
• Missiles (penetrating injury to the foot like a nail, or a gunshot wound).
• Delayed wound closure.
• Through and through oral injuries.

Local Anesthetic Maximum Dosing

The following are the maximum doses of local anesthetics:

• Lidocaine with epinephrine (EPI): 7 mg/kg.
• Lidocaine without EPI: 4 mg/kg.
• Bupivacaine with EPI: 3.5 mg/kg.
• Bupivacaine without EPI: 2.5 mg/kg.

Local Anesthetic Toxicity Symptoms

Toxicity can manifest in several systems:

• Early: Headache, tinnitus, metallic taste, perioral numbness, irritability.
• CNS Complications: Seizure, coma.
• CVS Complications: Ectopy, arrhythmias, decreased contractility, and arrest.
• Other: Methemoglobinemia.

Tissue Adhesives (Pros and Cons)

Tissue adhesives are beneficial but have limitations:

• Pros: Quick, cheap, comfortable, do not require removal, possess some antimicrobial properties, eliminate risk of needlestick injuries, and offer similar cosmesis to sutures.
• Cons: Can only be used for small wounds (less than 4 cm), cannot be used for wounds with high tension, incompatible with creams, cannot be submerged (will dissolve), and carry a higher risk of dehiscence due to lower tensile strength.

Suture Material and Dissolution

Suture materials can be biologic (higher reactivity, lower tensile strength, better knot security) or synthetic (lower reactivity, higher tensile strength, lower knot security).

• Common Biologic Examples: Cat gut, rapid gut, collagen, silk, linen, cotton.
• Rapid gut: 50% dissolved in 1 week.
• Regular gut: 50% dissolved within 4 weeks.
• Common Synthetic Examples: Dacron, nylon, proline, Vicryl, steel.
• Vicryl rapid: 50% dissolved in 1 week.
• Vicryl: 50% dissolved in 3 weeks.
• Non-dissolving: Nylon, proline, and steel.

Suture Removal Timelines

General timelines for suture removal:

• Face: 5 days.
• Most sutures: within 7 days.
• Limbs and joints: around 14 days.

Tetanus Prophylaxis

Prophylaxis includes immunization and immunoglobulin:

• Tetanus Immunization (TaP): Required if it has been 10 years since the last booster.
• Tetanus Immunoglobulin (TIG): Give 250 international units for an adult with any wound if they have an incomplete primary series (as per Rosens, CDC differs).

II. FOREIGN BODIES

Foreign Body Removal

Rectal Foreign Bodies:

• Digital removal.
• Removal with an anoscope and ring forceps.
• Use of a Foley catheter to break suction.
• Surgery.
• Non-standard technique: Filling hollow objects with plaster and a rope (Rosens has this listed, but please don't do this)

Body Packers vs. Body Stuffers:

• Body Packers: Swallow large amounts of well-packaged drugs.
• Treatment: Whole bowel irrigation. They must be monitored until they have three packet-free poops and a negative CT. If systemic toxicity occurs, immediate surgery is needed as the dose is likely lethal.
• Body Stuffers: Rapidly insert drugs (oral, vaginal, rectal); usually smaller amounts but poorer packaging. Higher likelihood of toxicity, but less significant than body packers if toxicity occurs.

ENT Foreign Bodies:

• Direct removal with forceps, blunt right angle hook, balloon catheter, or irrigation.
• Irrigation in the ear is contraindicated if the material is biologic (like a bean) or if there is a tympanic membrane (TM) perforation, in which case PO and topical antibiotics are required.
• If the object is an insect (bug), kill it chemically using 10% lidocaine spray, 2% lidocaine gel, alcohol, or mineral oil.

Airway Foreign Bodies:

• Infants: Five back blows followed by chest thrusts.
• Older than infants (awake): AHA recommends allowing them to cough if moving air. If not, then for Peds and adults to have 5 back blows and 5 abdominal thrusts, alternating.
• Unresponsive/CPR: CPR at 30 to 2 with mouth checks every time before breaths. Use a laryngoscope or NP scope and attempt removal with Magill forceps if visible.
• If unable to intubate, push the tube into the right main stem, remove it (may extract the foreign body), and then reintubate.

Esophageal Foreign Bodies:

• Three Most Likely Locations for Lodgement:
1. Cricopharyngeal muscle (at the clavicle on X-ray).
2. Mid-esophagus (at the aortic arch or carina).
3. Distally (at the GE junction).
• Coin Appearance: If in the esophagus, a coin will appear flat on an AP X-ray (if in the trachea, it appears on its long edge).

Endoscopy Indications (Immediate Removal):

• Sharp object.
• Object longer than 5 cm or wider than 2 cm.
• Button batteries (due to risk of pressure necrosis, corrosion, and electrical current damage).
• Multiple magnets.

Non-Invasive Removal Techniques:

• Glucagon (1 mg IV) (though not supported by literature).
• Coca-Cola (for fizziness and potential dissolving properties).
• Balloon catheter with fluoroscopy removal.

III. BITES AND STINGS

Mammalian Bites

Dog Bites:

• Primary Concern: Capnocytophaga canimorsus (30% mortality, higher in alcoholics, asplenic, and immunosuppressed people).
• Other Pathogens: Staph aureus, Pasteurella, Corynebacterium, Moraxella, Fusobacterium.
• Suturing: Can suture closed, except for hands and feet.
• Antibiotics: Only needed for hands, feet, and high-risk wounds.

Cat Bites:

• Primary Concern: Pasteurella multocida.
• Mortality: 30% mortality rate if P. multocida reaches the blood (higher in patients with liver disease, COPD, and malignancy).
• Suturing: Only suture the face.
• Antibiotics: Give antibiotics for all wounds that break the dermis.

General Animal Bite Antibiotics:

• PO: Amoxicillin-clavulanate (Amoxyclav).
• Alternatives PO: Ciprofloxacin or Clindamycin and Septra.
• IV (Admission): Ertapenem, Ampicillin-sulbactam, or Clindamycin and Ciprofloxacin.

Rodent Bites: Do not require prophylactic antibiotics, and wounds can be closed.

Monkey Bites:

• Require Amoxyclav and tetanus update.
• Require prophylaxis for Monkey B virus (Herpes B virus), which has an 80% mortality rate in humans.
• Prophylaxis Dosing: Valacyclovir for 14 days (generally required for every bite).

Human Bites:

• Primary Bacterial Concern: Eikenella corrodens.
• Viral Concerns: Give Post-Exposure Prophylaxis (PEP) for Hepatitis B virus and HIV if the biter is infected, or based on risk calculations and discussion.

Reptile and Spider Bites

Venomous Snake Families:

• Elapidae (Coral snake, Cobra): Carry a neurotoxin that blocks choline receptors.
• Treatment: Always need antivenom (3 to 5 vials).
• Viperidae (Pit vipers, Rattlesnakes): Carry a hemotoxic toxin.

Pit Viper Envenomation Grading Scale (0 to 4):

• Grade 0: No envenomation.
• Grade 1: local edema only
• Grade 2 (Systemic Symptoms Begin): Systemic symptoms are present and swelling is spreading.
• Grade 3: Vital sign changes (e.g., hypotension) and changes in DIC labs.
• Grade 4: Neuro symptoms (e.g., fasciculations).

Pit Viper Treatment (CROFAB):

• CROFAB (ovine derived antivenom) is given for all Grade 2 or more envenomations (aka systemic symptoms).
• Initial Dosing (Quick Guide): Grade of severity times 3 (number of vials).
• Maintenance Dosing (Quick Guide): Grade itself (number of vials).
• CROFAB is the first-line treatment for compartment syndrome secondary to a pit viper bite.
• Adverse Event: Serum sickness (Type III hypersensitivity) occurs in 15% of cases one week post-exposure.

Black Widow Spider (Lactrodectism):

• Toxin Type: Neurotoxic (causes increase in acetylcholine).
• Specific Symptoms: Hypertension, rigid abdomen, priapism.
• Management: Observe for at least 6 hours, give Diazepam for spasms.
• Antivenom (Lyovac): Given to pediatrics, elderly, pregnant patients, or those with severe symptoms (seizure, respiratory failure, uncontrolled hypertension/pain).

Brown Recluse Spider (Loxosceles reclusa):

• Toxin Type: Hemolytic, vasoconstrictive, necrotic toxin.
• Classic Sign: Red, white, and blue bite mark (inflammation, spasm, necrosis).
• Treatment: Supportive care; hyperbaric oxygen may benefit later wound healing. Antivenom is only available in Brazil.

Bark Scorpion (Centuroides sculpturatus):

• Toxin Type: Neurotoxin (opens sodium channels).
• Treatment: Ice, tetanus update, antivenom (available), Atropine (for hypersalivation/bradycardia), Nitroprusside (for hypertension).

Marine Stings

• Box Jellyfish: Can cause cardiac arrest.
• Treatment: Hot water submersion to inactivate the toxin. Also vinegar, ethanol, IV Verapamil, and antivenom (available).

IV. THERMAL BURNS

Burn Classification and Mortality

• Zones of Burn Injury (3): Central necrosis (irreversible), intermediate reversible stasis (target for resuscitation), and outer zone of inflammation.
• Mortality: Calculated via the Baux Score (TBSA + Age = Mortality). The LD50 is about 60 to 70% TBSA.

Burn Degrees/Classes:

• Superficial (First Degree): Red, blanches, heals in about 1 week.
• Superficial Partial (Second Degree): Red with blisters.
• Deep Partial (Second Degree): Red or white, may not blanch, wet appearance.
• Full Thickness (Third Degree): Leathery, charred, white, or yellow; does not blanch.
• Deep Full Thickness (Fourth Degree): Into muscle, tendon, or bone.
• Fifth Degree: Requires amputation.
• Note: Burns from superficial partial thickness and worse are counted within the TBSA calculation. Anything white or full thickness generally requires grafting.

Total Body Surface Area (TBSA) Estimation

• Palm Rule: A patient's palm (to fingertips) is 1% TBSA.
• Rule of Nines (Adults):
• Head and Neck: 9%.
• Anterior Thorax: 18%.
• Posterior Thorax: 18%.
• Each Arm: 9%.
• Each Leg: 18%.
• Groin: 1%.
• Rule of Nines (Pediatrics):
• Head: 18%.
• Each Leg: 14%.
• Otherwise same as adult

Burn Resuscitation Formulas and Goals

Most formulas estimate the total fluid required over 24 hours. Half of the total volume is given in the first 8 hours, and the remainder is given over the next 16 hours.

• Goal Urine Output: Adults: > 0.5 cc/kg/hr; Peds: 1 cc/kg/hr; Infants: 2 cc/kg/hr.
• Parkland: 4 cc/kg per TBSA.
• Modified Parkland: 3 cc/kg per TBSA.
• Brooke: 2 cc/kg per TBSA (0.5 cc of this volume is colloid infusion).
• Modified Brooke: 2 cc/kg per TBSA (Ringers Lactate only).
• Evans: 1 cc/kg per TBSA (Ringer's) + 1 cc/kg per TBSA (colloid) + 2 L of D5 water maintenance.
• Galveston (Peds): 5 L/m² TBSA + 2 L/m² TBSA (maintenance).
• Rule of 10 (Hourly Rate): TBSA times 10 cc/hour. If the patient is over 80 kg, add 100 cc/hour per 10 kg over the 80 kg threshold.

Burn Center Referral (10/3 CRISPLET Mnemonic)

A patient should be referred to a burn center if they meet any of these criteria:

• 10% TBSA.
• Third-degree burns, any.
• Chemical burns.
• Rascals (pediatrics).
• Inhalational injuries.
• Social factors.
• Past medical history/co-morbidities.
• Location (hands, face, feet, or groin).
• Electrical burns.
• Trauma associated.

Escharotomy Indications

Escharotomies are required when circumferential burns compromise circulation or ventilation:

• Chest: Difficulty with ventilation or high airway pressures.
• Neck: Airway compromise or neck vessel distension.
• Extremity: Decreased Doppler, or pulses showing 90% of the other side or an overall decreased pulse.

V. CHEMICAL EXPOSURES

Decontamination

Decontamination should occur on scene with Hazmat.

• General: All clothing must be removed.
• Dry Chemicals (e.g., dry lime, elemental metals, phenol, lye): Must be brushed off first.
• Wet Chemicals: Must be sprayed down with water for 10 or 15 minutes.

Mechanism of Injury

• Acid: Causes coagulation necrosis, forming an eschar that limits penetration.
• Bases: Cause liquefaction necrosis and saponification, which increases penetration and causes deeper damage.

Ocular Burns (Dua Classification)

The classification is based on limbal and conjunctival involvement. The primary treatment is copious irrigation of at least 2 L until the pH is 7.4. Any grade 2 or above requires an Emergency Department ophthalmology consult. Grading is based on a clock face.

• Grade 1: No limbal and no conjunctival involvement seen afterwards.
• Grade 2: Less than 3 hours limbal involvement and less than 30% conjunctival involvement.
• Grade 3: 3 to 6 hours limbal involvement and 30 to 50% conjunctival involvement.
• Grade 4: 6 to 9 hours limbal involvement and 50 to 75% conjunctival involvement.
• Grade 5: 9 to 12 hours limbal involvement and 75 to 100% conjunctival involvement.
• Grade 6: Complete (12 hours) limbal involvement and 100% conjunctival involvement.

Methemoglobinemia (MetHb)

MetHb occurs when Fe2+ is oxidized to the Fe3+ (ferric) state, rendering hemoglobin unable to carry oxygen.

• MetHb Symptoms by Percentage:
• 10%: Cyanosis with hypoxia.
• 20%: Headache, anxiety, increased respiratory rate and pulse.
• 50%: Confused, lethargic, acidotic.
• 70%: Coma, seizure, dysrhythmia, and death.
• Treatment:
• Methylene blue: 1 to 2 mg/kg of the 1% product.
• If G6PD deficiency is present (Methylene blue is contraindicated): Use Vitamin C or exchange transfusion.

Hydrofluoric (HF) Acid

HF acid is highly toxic because free fluoride binds calcium and magnesium, blocks ATPase, and blocks the Krebs cycle.

• Treatment Protocol:
1. Copious irrigation with water for 15 minutes.
2. Remove blisters (which may contain HF acid).
3. Topical: Calcium gluconate 3.5 g in KY jelly.
4. Subcutaneous: Injections of 10% calcium gluconate.
5. Intra-arterial: 10 mL of 10% calcium gluconate over 4 hours.
6. IV infusions to replete calcium and magnesium.

Phosphorus and Formic Acid

• Phosphorus (White, Elemental, Red): Found in munitions.
• Treatment: Water submersion of the burn and supportive care.
• Formic Acid: Causes metabolic acidosis.
• Treatment: Wound lavage, Bicarb for acidosis, folate, dialysis/exchange transfusion.

Chemical Warfare Agents

There are four types of agents:

1. Nerve Agents (e.g., Sarin, VX): Block acetylcholine esterases.
   • Symptoms (Cholinergic Toxidrome): Salivation, defecation, urination, lacrimation, bronchorrhea, bradycardia, and bronchoconstriction.
   • Treatment Dosing:
   • Atropine (until drying of airway secretions).
   • 2-PAM: 30 mg/kg initially, then 10 mg/kg/hour maintenance.
   • Benzodiazepines (for seizures).
2. Vesicants (e.g., Mustard Agents): Cause blisters; Mustard agents have a fishy/garlic odor and no immediate pain.
3. Choking Agents (e.g., Phosgene, Chlorine): Cause pulmonary edema.
4. Cellular Asphyxiants (e.g., Hydrogen cyanide).

⚕️ Pediatric Medicine Topics: Clinical Review

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.

I. Pediatric Diarrhea and Dehydration

A. Etiologies of Bloody Diarrhea (Pneumonic: SYSCO + Ciff)

• C - Clostridium difficile (C Diff)

• S - Salmonella

• Y - Yersinia

• S - Shigella

• C - Campylobacter

• O - O157:H7 E. coli

B. Reasons Diarrhea is Worse in Pediatrics

• Larger extracellular fluid compartment (more fluid to lose rapidly).

• Higher metabolism (turn over fluid more quickly).

• Lower glycogen, oxygen, and fat stores (less stores of fluid).

• Kidneys have a decreased ability to conserve water.

• Higher total body water content and surface area (to lose fluid through other means).

C. Treatment Specifics

• Antibiotics and antimotility agents should not be used if there is bloody diarrhea (due to concern for O157:H7).

• Antibiotics for Invasive Pathogens (Non-bloody): Cipro (once species is confirmed to not be Shiga toxin producing).

• C. diff: PO Vancomycin.

• Cryptosporidium: Nitazoxanide.

• Giardia and Entamoeba: Flagyl (Metronidazole).

D. Indications for Evaluation, Culture, and Hospitalization with diarrhea (Pneumonic: DAMSON)

• D - Dysentery (bloody diarrhea).

• A - Age:

  • Less than 6 months old (should be investigated).

  • Less than 3 months old (should be admitted).

  • Duration more than 2 weeks (culture should be obtained).

• M - Medical problems.

• S - Systemic illness or complications.

• O - Output decreased or significant dehydration.

• N - Not improving despite treatment.

E. Dehydration Assessment and Treatment Specifics

💡 Clinical Dehydration Scale (TEAM)

• T - Tears (0 to 2 points).

• E - Eyes (whether they are sunken, 0 to 2 points).

• A - Appearance (e.g., interactive, lethargic, 0 to 2 points).

• M - Mucous membranes (0 to 2 points).

• Scoring: 1 to 4 points total is considered mild.

Dehydration Severity Guide

• Mild

  • Total Body Water Deficit: 3 to 5%

  • Fluid Deficit (mls/kg): 30 to 50 mls/kg

  • Fluid Repletion Plan: Replete total fluid over 4 hours (ideally orally).

• Moderate

  • Total Body Water Deficit: 6 to 10%

  • Fluid Deficit (mls/kg): 60 to 100 mls/kg

  • Fluid Repletion Plan: Replete total fluid over 4 hours (ideally orally).

• Severe

  • Total Body Water Deficit: 10% plus

  • Fluid Deficit (mls/kg): Greater than 100 mls/kg

  • Fluid Repletion Plan: 1. Give 20 cc/kg fluid bolus. 2. Give remaining 10% deficit over 24 hours (first half in 8 hours, second half in 16 hours). 3. Add maintenance fluids on top.

II. Pediatric Nephrology and Urology

A. Priapism Etiologies (Pneumonic: THANKS TF)

• These are low-flow causes (ischemia, acidosis, pain):

  • T - Toxin (spider/scorpion bites/stings).

  • H - Hematology (Sickle cell disease, leukemia, thalassemia, TTP, HUS, polycythemia).

  • A - Anti-drugs (Anti-hypertensives, anti-depressants, antipsychotics, anticoagulants, anti-PDE5).

  • N - Neurogenic.

  • K - Krebs (Metabolic: Gout, hyperlipidemia, diabetes).

  • S - Street drugs (Meth, cocaine, alcohol, marijuana).

• These are high-flow causes (less pain, no acidosis/ischemia):

  • T - Trauma or lacerations.

  • F - Fistula (AV).

B. Priapism Management Specifics

• Analgesia: Dorsal nerve or ring block.

• Medication Trial: Terbutaline 10 mg PO every 15 minutes.

• Ambulation: Try getting them to walk around.

• Aspiration/Instillation:

  • Insert 18 gauge needle into corpus cavernosum.

  • Aspirate 20 to 30 cc's of blood.

  • Instill 100 micrograms of phenylephrine every 5 minutes as needed.

• Consult: Call urology if all fails.

C. Paraphimosis Management

• Analgesia (dorsal or ring block).

• Compression or moist gauze with sugar on the foreskin.

• Manual reduction (thumbs and forefingers).

• Add Addison forceps for traction if manual reduction fails.

• Micro puncture the foreskin to reduce swelling.

• Consult urology or perform a dorsal slit (in the community setting).

D. Pediatric Hematuria Causes

• Systemic (Bleeding/Clots): HUS, TTP, HSP, Sickle cell disease, leukemia, lupus, bleeding disorders, anti-coagulant medications.

• Extra Renal (within the urinary tract): Trauma, stones, tumor, infections (cystitis), menstruation, foreign bodies.

• Renal: Pyelonephritis, stone, tumor, nephritis, AIN (Acute Interstitial Nephritis), or ATN (Acute Tubular Necrosis).

E. Pediatric UTI Workup and Treatment Specifics

• Age Group:

  • Workup/Imaging: Full septic workup (as you'd only recognize this if there's a fever), catheterization, admission.

  • Treatment: Amp, Gent.

  • Duration: Admitted.

• Age Group: 2 months - 2 years

  • Workup/Imaging: Screen with bag urine (if positive, confirm with cath urine). Renal ultrasound (after first UTI). VCUG (after second UTI, or if significant hydronephrosis on ultrasound).

  • Treatment: Amoxiclav, 3rd gen cephalosporin, or Septra.

  • Duration: 7 to 10 days.

• Age Group: > 2 years (Cystitis)

  • Workup/Imaging: Based on symptoms.

  • Treatment: Keflex (simple) or upper tract agents.

  • Duration: 3 days.

• Age Group: > 2 years (Pyelonephritis i.e. upper tract)

  • Workup/Imaging: Based on symptoms.

  • Treatment: Amoxiclav, 3rd gen cephalosporin, or Septra.

  • Duration: 7 to 10 days.

Note: UTI Risk Factors: Females 39°C; History of UTI.

F. Pediatric Hypertension Differential (Pneumonic: VECTOR)

• V - Vascular (HSP, Kawasaki, renal artery stenosis or clot).

• E - Endocrine (Thyroid, pheochromocytoma, or Cushing's).

• C - Cardiac (Coarctation or CHF).

• T - Toxin (Cocaine or Meth).

• O - Oncology (Wilms tumor, neuroblastoma, pheochromocytoma).

• R - Renal (HSP, HUS, polycystic kidney disease, or nephritis).

G. Hemolytic Uremic Syndrome (HUS) (Pneumonic: FAT RN)

• F - Fever.

• A - Anemia (microangiopathic).

• T - Thrombocytopenia.

• R - Renal involvement.

• N - Neuro involvement.

• Specific Triad: Anemia, thrombocytopenia, and renal involvement.

• Management: Supportive, transfuse as needed, plasma pheresis. If complement mediated, Eculizumab can be given.

H. Henoch-Schönlein Purpura (HSP) Symptoms (Pneumonic: ARENA)

• A - Abdo pain.

• R - Rash (palpable purpura in dependent areas).

• E - ESR.

• N - Nephritis.

• A - Arthralgias.

• Common Causes: Post-viral, Mycoplasma, Campylobacter, drugs, horse serum, cold, insect bites.

I. Nephrotic vs. Nephritic Syndrome

• Nephrotic Syndrome

  • Pathophysiology & Specific Values: Loss of protein through kidneys. Diagnostic Values: Protein on dip (3+ or more) or 24-hour loss (3.5 grams or more). Low albumin (less than 25). High lipids (liver compensation).

  • Key Features: Edema (due to low protein). High VTE risk (clots).

• Nephritic Syndrome

  • Pathophysiology & Specific Values: Inflammation leading to hypertension, hematuria, and renal failure.

  • Key Features: Hypertension. Hematuria. Renal failure.

Note: Workup for Nephrotic and Nephritic Syndromes: SPEP, UPEP, ACR, IgA levels, ANCA, ANA, C3C4, ASOT, and anti-GBM.

III. Pediatric Neurology

A. Altered Mental Status (Pneumonic: AEIOU TIPS or DIMS)

• A - Ammonia or Alcohol.

• E - Electrolytes.

• I - Insulin, Inborn errors, or Insomnia.

• O - Oxygen (Hypoxia) or Overdose.

• U - Uremia.

• T - Trauma or Tumors.

• I - Infection.

• P - Psych.

• S - Seizures or Subarachnoid hemorrhage.

B. Meningitis

• Causes (

• Causes (General): Strep pneumo, N. meningitidis, H. flu (less common due to vaccination).

Treatment by Age Group:

• 0 to 28 days old: Ampicillin + Cefotaxime + maybe Acyclovir.

• Over 1 month old: Ceftriaxone + Vancomycin + maybe Acyclovir.

Additional Notes:

• Risk Factors for HSV encephalitis: Maternal herpes, newborn vesicles, seizures, or focal neuro deficits.

• Indications for CT before LP (Increased ICP): Focal deficits, seizures, significantly altered mental status, signs of elevated ICP (Cushing Triad or Papilledema), trauma, immunocompromised status, or history of CNS disease.

• Indications for Steroids: Give before or with antibiotics in infants over 6 weeks old if H. flu (benefit for hearing loss) or Strep pneumo (mortality benefit) is suspected.

C. Seizures Management and Specifics

• Causes (Pneumonic: DIMS):

  • D - Drugs/Toxins (mushrooms, jet fuel, withdrawal, TCAs overdose).

  • I - Infection (meningitis, encephalitis).

  • M - Metabolic (electrolytes, glucose, oxygen/hypoxia).

  • S - Structural (masses, bleeds, TBI, strokes).

• Indications for CT after Seizure: Continuing reduced level of consciousness, focal deficit, trauma, partial/focal onset seizure, or continued bad headache. (Generally required unless generalized seizure with return to baseline and no status, or known history matching previous seizures).

Initial Management (Dosing) by Age Group:

• Neonates: Phenobarb 20 mg/kg. Then anti-epileptic drug or Midazolam.

• Infants (Status): Benzodiazepines x 2 (Ativan or Midazolam) then AED.

Anti-Epileptic Drug Dosing (Infants/Status):

• Keppra at 60 mg/kg.

• Valproic acid at 40 mg/kg.

• Fosphenytoin at 20 mg/kg.

• Note: Repeat the anti-epileptic drug with a different agent before moving on.

Simple Febrile Seizure Criteria

• Age: 6 months to 6 years old.

• Duration: Lasting less than 15 minutes.

• Type: Must be generalized.

• Frequency: Must be a single episode in 24 hours.

• Baseline: Must be neurodevelopmentally normal and return to baseline.

• Workup: If all criteria are met, the only necessary workup is for the fever.

D. Pediatric Ataxia

• Most Common: Acute cerebellar ataxia post-Varicella or Coxsackievirus.

• Other Post-Infectious: Demyelinating encephalopathy (ADEM, Listeria, Enterovirus); Brainstem encephalitis (EBV, Listeria, Enterovirus).

• Miller Fisher GBS Triad: Ataxia and areflexia (Weakness is descending, unlike classic GBS).

• CSF findings: High protein and normal white blood cells.

E. Pediatric Stroke Risk Factors (mnemonic: BET)

• B - Bleed (Trauma, Moyamoya, sympathomimetic use).

• E - Embolic (Congenital heart disease, endocarditis, pre- or post-op).

• T - Thrombotic (Sickle cell disease, vasculitis, pregnancy, OCP, migraine, lupus, HUS).

F. Vertigo Categories

• Acute Vestibular Syndrome (Constant Vertigo):

  • Posterior stroke, posterior bleed, abscess, or mass.

  • Vestibular neuritis (no hearing loss).

  • Labyrinthitis (recent URI, with hearing loss; requires steroids and acute otitis media treatment if present).

• Spontaneous Episodic Vestibular Syndrome:

  • TIAs, vestibular migraines, cardiac dysrhythmias.

  • Meniere's disease (episodic, spontaneous, caused by fluid in the ear, has hearing loss).

• Triggered Episodic Vestibular Syndrome:

  • BPPV and CPPV (uncommon in pediatrics).

  • Orthostatic hypotension.

IV. Pediatric Musculoskeletal (MSK)

A. Salter Harris Classification (Pneumonic: SALTER)

• S - Straight through the physis.

• A - Above and through the physis (Metaphyseal into the physis and out).

• L - Lower (Through the physis and down through the joint of the epiphysis).

• T - Through the physis (Above and below).

• ER - Erasing of the physis.

B. Gartland Classification (Supracondylar Fractures)

1. Non-displaced.

2. Displaced with the posterior cortex intact (like a hinge).

3. Displaced with no cortex intact. Even the periosteum is disrupted.

   1. Diagnostic Value: Bowman's angle (normally 75 to 80°) can help find subtle supracondylar fractures.

   2. Complications: Volkmann's contracture/ischemia, gunstock deformity (varus deformity), brachial artery injury, nerve injuries (predominantly median, also radial).

C. Elbow Ossification Centers (nmemonic: CRITOE)

• C - Capitellum (1 year).

• R - Radial head (3 years).

• I - Internal epicondyle (5 years).

• T - Trochlea (7 years).

• O - Olecranon (9 years).

• E - External epicondyle (11 years).

D. Forearm Fractures (Mnemonic: MUGR)

• MU - Monteggia: Ulnar fractured with a dislocation of the radial head.

• GR - Galeazzi: Radius fractured and the ulna is dislocated through a DRUJ injury.

• Essex-Lopresti: Radial head is fractured with a DRUJ injury (similar to Galeazzi but different fracture location).

E. Developmental Dysplasia of the Hip (DDH)

• Risk Factors: Female, family history, breech presentation, oligohydramnios, big baby, post-dates, swaddling (especially through the bottom part).

• Diagnostic Values (Shenton Line):

  • Abnormal: More than 30°.

  • Dislocation: More than 40°.

• Physical Exam (

• Physical Exam (> 6 weeks): Increased abduction and a leg length discrepancy.

• Treatment:

  • Less than 6 weeks: Pavlik harness.

  • Greater than 6 weeks: Hip spica.

F. Pediatric Limp Differential (Mnemonic LIMPSS)

• L - Legg-Calvé-Perthes.

• I - Infection (septic joint, osteomyelitis, Lyme disease, transient synovitis).

• M - Malignancy (Ewing's, osteosarcoma, leukemia, or mets).

• P - Pain from trauma (fractures or non-accidental injuries).

• S - SCFE (Slipped Capital Femoral Epiphysis).

• S - Something in the abdomen (torsion, ectopics, etc.).

G. Septic Hip Screen (Kocher Criteria - Mnemonic: FEW WALK)

• F - Fever over 38.5°C.

• E - ESR over 40.

• W - WBC over 12.

• WALK - Unable to ambulate on the affected side in the emergency department.

• Note: Meeting any of these criteria suggests a non-zero chance of septic hip, requiring an ultrasound.

H. Septic Arthritis Organisms (Bugs)

• Less than 2 years old: GBS, Gram negative bacteria, Gonorrhea, Staph aureus.

• Otherwise: Staph aureus or GAS (most likely).

• Sexually Active: Gonorrhea.

• Sickle Cell Disease: Salmonella.

• IV Drug User/Immunocompromised: Gram negative (Pseudomonas).

• Specific: Kingella kingae (can present with normal labs).

Synovial Fluid Analysis Values (from Rosen's)

• Negative Fluid Analysis (Normal):

  • WBCs: Less than 5,000.

  • PMNs: Less than 25%.

• Positive Fluid Analysis (Bacterial):

  • WBCs: Greater than 50,000.

  • PMNs: Greater than 90%.

• Inflammatory/Equivocal Region:

  • WBCs: Between 8,000 and 20,000.

  • PMNs: Over 70%.

• Practical Rule: If WBCs are over 5,000 AND there are more than 25% PMNs, bacterial septic joint cannot be ruled out.

I. Slipped Capital Femoral Epiphysis (SCFE)

• Common Age: 12 to 16 year olds.

• Risk Factors: Obesity, male, CKD, radiation, hypothyroidism, growth hormone deficiencies, hypopituitary, renal osteodystrophy.

• X-ray Findings: Slippage of the epiphysis, positive Klein's line (line down femoral neck should transect physis), Steel sign (crescent-shaped, hyperdense overlap area), widened physis.

• Classification by Shaft Angle (Southwick):

  • Mild: Less than 30°.

  • Moderate: 30 to 50°.

  • Severe: Greater than 50°.

• Management:

  • Unstable SCFE: Non-weightbearing and emergent orthopedics consult.

  • Stable SCFE: Non-weightbearing and outpatient orthopedic follow-up (though discussion with ortho is recommended).

J. Legg-Calvé-Perthes Disease (LCPD)

• Common Age: 3 to 12 year olds.

• Pathophysiology: Avascular necrosis of the femoral head.

• Management: Technically follow up with ortho as an outpatient for bracing or surgical management; may be weightbearing as tolerated (though discussion with ortho is recommended).

K. Tibial Fractures

• Tillaux Fracture: Salter Harris III fracture of the anterolateral tibial epiphysis.

  • Management: Non-weightbearing, immobilized, consult ortho.

• Triplane Fracture: Salter Harris IV (fractures through the epiphysis, physis, and up through the metaphysis of tibia).

  • Management: Non-weightbearing, immobilized, consult ortho.

V. Pediatric Drugs and Infectious Disease

A. Drugs to Avoid in Pediatrics

• Ceftriaxone (less than 1 month): Can displace bilirubin.

• Septra (less than 1 month): Can displace bilirubin.

• NSAIDs (less than 6 months): Can harm kidneys.

• Over-the-counter cold medications (less than 5 years old).

• Aspirin (less than 15 years old): Risk of Reye's disease.

• Codeine (irregular metabolism).

• Pheninomes.

B. Lyme Disease (Specifics)

• Cause: Spirochete Borrelia burgdorferi.

• Vector: Deer tick (Ixodes scapularis).

• Stages: Early localized (flu-like illness, erythema migrans); Disseminated (arthritis, carditis, Bell's palsy, encephalitis); Late stage (arthritis, encephalitis).

• Diagnosis: Clinically, then Enzyme Immunoassay (EIA) followed by Western blot.

• Treatment: Amoxicillin or Doxycycline (varying durations). If Meningitis or Encephalitis is present, use Ceftriaxone instead.

VI. Non-Accidental Trauma (NAT)

A. Highly Specific Injuries/Locations

• TEN 4 FACES:

  • T - Torso.

  • E - Ears.

  • N - Neck.

  • 4 - Bruises in children less than 4 months old.

  • F - Frenulum.

  • A - Angle of the jaw.

  • C - Cheeks.

  • E - Eyelids.

  • S - Subconjunctival.

  • P - Patterned bruises or patterned burns.

B. Concerning Fracture Patterns

• Classic metaphysical injury (corner fracture).

• Long bone fractures if the child is not walking.

• Complex skull fractures.

• Fractures at different stages of healing.

• Posterior rib fractures (from shaking).

• Scapula fractures (from shaking).

• Femur fractures.

C. Mimics of NAT (Conditions Causing Brittle Bones)

• Osteogenesis Imperfecta.

• Rickets, Vitamin C deficiency, High Vitamin A.

• Syphilis, Osteomyelitis.

• Bone tumors or mets, Leukemia.

• Congenital insensitivity to pain.

D. NAT Workup and Admission Protocol (Mnemonic: A CRASH)

• Call CAS (Child Protective Services) and admit the patient.

• Perform the following tests:

  • A - AST or ALT (if less than 5 years old). (Abdo CT required if AST or ALT are over 80).

  • C - All Contacts (siblings less than 2 years old should get a skeletal survey).

  • R - Retinal exam (if TBI is present).

  • A - Abdo CT (if AST or ALT are over 80 or if history/physical suggests abdominal trauma).

  • S - Skeletal Survey (all 21 pictures) (required if less than 2 years old; maybe if less than 5 years old).

  • H - Head CT (required if less than 6 months old due to difficult neuro exam, or if any history/features of head trauma or signs of shaking).

Pediatrics 2 of 3 Pediatric Respiratory Topics

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care. 1. Asthma Assessment Tool: PRAM (Pediatric Respiratory Assessment Measure) The scoring system ranges from 0 to 12 points. The mnemonic provided is WE SOS.

• W (Wheeze): 0 to 3 points
• E (Air Entry): 0 to 3 points
• S (Suprasternal In-drawing): 0 to 2 points
• O (Oxygen Saturation): 0 points (>94%), 1 point (92 to 94%), 2 points (
• S (Scalene Retractions): 0 to 2 points

Severity Scoring:

• Mild: 1 to 3 points.
• Moderate: 4 to 7 points.
• Severe: 8 to 12 points, or the presence of cyanosis or altered level of consciousness.

Treatment and Dosing:

• Mild Asthma:
  • Ventolin (SABA): Every 20 minutes. Dose: 4 puffs (8 puffs (>20 kg). Give three rounds.
  • Dexamethasone (DEX): 0.6 mg/kg PO (give two doses: one now, and one dose to take tomorrow).
• Moderate Asthma:
  • Ventolin and Ipratropium Bromide: Both given every 20 minutes for three rounds.
    • Ipratropium Bromide Nebs: 250 micrograms (500 micrograms (>20 kg).
    • Ventolin Nebs: 0.15/kg/dose (5mg) up to 3/hr for continuous
  • DEX is also given.
• Severe Asthma:
  • Continuous nebulized Ventolin and Ipratropium Bromide.
  • DEX or Methylprednisolone.
  • Methylprednisolone Dose: 1 mg/kg.
  • Magnesium: 50 mg/kg (can be repeated every 20 minutes as needed).
  • Other options: Epi, epi infusion, inhaled epinephrine, ketamine, or heliox.

Admission and Discharge Criteria:

• Admission Criteria: Oxygen saturation less than 90%, respiratory distress, social concerns, comorbidities, or requiring a SABA more than every 4 hours.
• Discharge Criteria: The patient must be able to tolerate 4 hours without receiving a round of Ventolin.
• Take-Home Ventolin Dosing: Four puffs every 4 hours for 4 days.

2. Bronchiolitis Common Age: Less than one to less than three-year-olds. Scoring System Mnemonic: WE SOS for Real.

• W (Wheeze).
• E (Air Entry).
• S (Substernal In-drawing).
• O (Oxygen Saturation).
• S (Scalene or Abdominal Retractions).
• F (Feeding).
• R (Respiratory Rate): Less than 60 (normal), 60 to 70 (worse), greater than 70 (even worse).

Treatment:

• Oxygen for saturations less than 94%.
• Nasal suctioning.
• Trial of Ventolin (if it works, keep doing Ventolin).
• If Ventolin works, give Steroids.
• Volume repletion (by feeding or IV fluids).
• May also try nebulized or IM epinephrine.

Admission Criteria (CPS): 90 RASCAL.

• 90: Less than 90% oxygen saturation.
• R: Respiratory distress.
• A: Apnea.
• S: Social concerns.
• C: Comorbidities (especially cardiac or pulmonary conditions).
• A: Age less than 3 months or if premature.
• L: Lactation or not tolerating feeds.

3. Croup (Laryngotracheobronchitis) Common Age: 6 Month to 6 year olds. Scoring System: Wesley Croup Score. The mnemonic provided is CRIES.

• C (Cyanosis): 0 or 5 points
• R (Retractions): 0 to 3 points
• I (Impaired Consciousness): 0 or 5 points
• E (Air Entry): 0 to 2 points
• S (Stridor): 0 to 2 points

Severity Scoring:

• Mild: 0 to 3 points (stridor only when upset).
• Moderate: 4 to 6 points (stridor at rest).
• Severe: 7 plus points (stridor at rest, severe respiratory distress).

Treatment and Dosing:

• Mild Croup: Dexamethasone: 0.6 mg/kg (one dose now, and one dose to be taken in 24 hours).
• Moderate/Severe Croup (stridor at rest):
  • Dexamethasone 0.6 mg/kg
  • Racemic Epinephrine: 2.25% concentration. Dose: 0.1 mL per kilogram up to 0.5 mL (usually 0.5 mL). Can be repeated every 20 minutes as needed.
    • Monitoring: Due to the dose lasting 2 to 3 hours, patients must be monitored for at least 3 hours after their last dose of racemic epinephrine.
  • Severe Croup may also require intubation or IM/IV epinephrine.

Admission Criteria: Uses the 90 RASCAL mnemonic (similar to bronchiolitis), but also specifically includes stridor despite treatment and does not include apnea.

ENT & Head/Neck Infections

• Epiglottitis
  • Age Group: 5–7 years old or older
  • Common Bugs: H. flu (historically), Group A strep, S. aureus, S. pneumoniae
  • Treatment Specifics: Airway management/ICU monitoring, Ceftriaxone and Vancomycin.
• Tracheitis
  • Age Group: 3–5 years old
  • Common Bugs: Often mixed, potentially predominantly S. aureus
  • Treatment Specifics: Airway management/ICU monitoring, Ceftriaxone and Vancomycin.
• Retropharyngeal Abscess (RPA)
  • Age Group: 6 months to 3 years old
  • Common Bugs: Group A strep, S. pneumoniae, S. aureus, Fusobacterium
  • Treatment Specifics: Ceftriaxone and Clindamycin (due to anaerobes). Requires surgical consult, especially if the abscess is greater than 2 cm in size.
• Peritonsillar Abscess (PTA)
  • Age Group: 15–30 years old
  • Common Bugs: Mixed, Group A strep, S. aureus, Fusobacterium
  • Treatment Specifics: Ceftriaxone or Clindamycin. Needs drainage (needle aspiration or I&D). Maybe safe for discharge home on Amoxicillin/Clavulanate (amoxy clav) for 10 days.
• Lemierre's Syndrome
  • Age Group: 15–24 years old
  • Common Bugs: Group A strep, Fusobacterium (accounts for about a third of infections)
  • Treatment Specifics: Ampicillin/Sulbactam, Piperacillin/Tazobactam, or Carbapenem. Diagnosis via CT neck with contrast.

Lemierre's Syndrome Classic Triad: Pharyngitis, anterior neck tenderness and swelling, and non-cavitary pulmonary infiltrates (from septic emboli).

4. Acute Otitis Media (AOM) Watch and Wait Criteria (CPS): Must be met for observation to be acceptable.

1. Healthy, immunized, and over 6 months.
2. Well appearing.
3. Temperature less than 39° C.
4. Less than 2 days of symptoms.
5. Able to sleep well with mild pain.
6. Intact tympanic membrane (TM) with no discharge.
7. Unilateral infection.

Treatment (Moderate to Severe AOM): Pain control and antibiotics.

• Antibiotic Duration: 10 days (6 months to 2 years old); 5 days (over 2 years old).
• Amoxicillin Dosing (Most Common): 90 mg/kg per day divided into two doses. Other options include Cefuroxime or Amoxicillin/Clavulanate.
• Ear Tubes: Patients can go home with Ciprodex drops.

5. Pertussis (Bordetella pertussis) Incubation Period: 12 to 17 days. Three Phases:

1. Catarrhal Phase: Dry cough, rhinorrhea, mild fever (looks like a mild viral infection).
2. Paroxysmal Phase: Violent coughing paroxysms (8 to 10 coughs) followed by a whoop. This phase lasts 2 to 4 weeks.
3. Convalescent Stage: Gradual improvement, though cough can linger up to 8 weeks.

Treatment: Azithromycin for the patient as well as contacts. Admission Criteria: Less than 3 months old or premature, or less than a year old with significant symptoms.

Cardiovascular Topics 6. Congenital Heart Disease (General) Ductal Closure: The PFO closes at about 6 months. The PDA closes within 1 to 3 days. Prostaglandin E1 (PGE1) Dosing (for ductal-dependent lesions): 0.05 micrograms per kilogram per minute, titrated to effect.

• Side Effects: Apnea, hypotension, seizures, fever.

Specific Diagnostic Testing:

• 4limb Blood Pressure Test: Upper extremity BP greater than lower extremity BP by 20 points is concerning (e.g., for coarctation).
• Pre and Post-ductal Sats: Measure at the right arm and left leg. Concerning if the right arm is less than 90% or if there is a 3% difference between the two limbs.
• Hyperoxia Test (100% O2):
  • Poor Man's Test: Less than 10% increase in saturation is concerning.
  • True Test: Less than 100 mmHg increase in PaO2 is concerning for a right-to-left shunt. Greater than 250 mmHg rules out a right-to-left shunt.

Lesion Categories:

• Cyanotic Lesions: Tetralogy of Fallot (TOF), Truncus Arteriosus, Total Anomalous Pulmonary Vein Connection (TAPVC), Transposition of the Great Arteries (TGA), Tricuspid Atresia, Pulmonary Atresia or Stenosis.
• Obstructive Lesions (Lead to shock/gray baby, present in first few weeks): Severe Aortic Stenosis, Interrupted Aortic Arch, Coarctation of the Aorta, Hypoplastic Left Heart.
• CHF/Mixing Lesions (Present at 1 to 3 months): VSD, large ASD, PDA.

7. Tetralogy of Fallot (TOF) and Tet Spells The Four Lesions (TET): VSD, RV outflow obstruction, overriding aorta, and RV hypertrophy. Treatment for TET Spell (right-to-left shunting):

• Decrease Tachycardia: Anxiolysis or knee-to-chest position.
• Increase SVR (Systemic Vascular Resistance): Knee-to-chest position, fluid bolus, or possibly Phenylephrine.
• Decrease PVR (Pulmonary Vascular Resistance): Oxygen.

8. Kawasaki Disease Diagnosis Mnemonic: WARM CREAM. Diagnosis is clinical, based on fever for 5 or more days PLUS 4 out of 5 of the following criteria:

• C: Conjunctival injection.
• R: Rash (generalized, polymorphous).
• E: Erythematous palms and soles.
• A: Adenopathy (cervical, unilateral, more than 1.5 cm).
• M: Mucous membrane changes (dry cracked lips or strawberry tongue).

Incomplete Kawasaki Disease: Fever for 5 days PLUS 2 or 3 criteria.

• Labs: Order CRP and ESR.
• Diagnostic Values: Elevated CRP (more than 30) or ESR (more than 40).
  • If elevated and 3 criteria met: Treat as Kawasaki and order echo.
  • If elevated and 2 criteria met: Admit, order echo, and draw supplemental labs (including WBC > 15, Platelets > 450, albumin <30).

Treatment and Dosing:

• IVIG: 2 grams per kilogram (single dose).
• Aspirin: 30 to 50 mg/kg daily orally in four divided doses.

9. SVT versus Sinus Tachycardia (Pediatrics) SVT Rate Thresholds (Faster than Sinus Tachycardia):

• Infants: Over 220 bpm.
• Older Children: Greater than 180 bpm.

Other Differences: SVT is very regular (maintained R-R intervals), unlike sinus tachycardia, which varies with activity or respirations. SVT may lack P waves or have inverted P waves coming after the QRS.

10. Rheumatic Fever (Jones Criteria) Prerequisite: Documented diagnosis of a Group A Strep infection. Diagnostic Criteria: Two Major OR One Major and Two Minor criteria must be met. Major Criteria (Jones, where O is the heart):

• J: Joints (Arthritis with swelling).
• O (Heart): Carditis.
• N: Nodules (Subcutaneous nodules).
• E: Erythema Marginatum.
• S: Sydenham Chorea.

Minor Criteria (FAPE):

• F: Fever.
• A: Arthralgia (without swelling).
• P: PR interval prolongation.
• E: ESR or CRP elevation.

Gastrointestinal Topics 11. Neonatal Jaundice (Hyperbilirubinemia) Bilirubin Thresholds:

• Bilirubin level over 85 can cause jaundice.
• Bilirubin level over 340 is a risk factor for kernicterus.

Indications for Further Investigation:

• Jaundice within the first day of life.
• Jaundice beyond 3 weeks of life.
• Sick appearing infant.
• Elevated conjugated bilirubin (always pathological).
• Rapidly rising bilirubin level.
• Total serum bilirubin not responding to phototherapy and approaching the exchange transfusion threshold.

Neurotoxicity Risk Factors (Lower Threshold for Phototherapy): Isoimmune hemolytic disease, G6PD deficiency, asphyxia, lethargy, temperature instability, sepsis, acidosis, and Albumin less than 30. Causes of Unconjugated (Indirect) Hyperbilirubinemia (Examples): Physiological jaundice, breast milk jaundice, hemolysis (e.g., ABO incompatibility, G6PD deficiency), GI obstruction (e.g., pyloric stenosis), and metabolic conditions (e.g., Gilbert syndrome). Causes of Conjugated (Direct) Hyperbilirubinemia (Always Pathological): Infections (e.g., sepsis, TORCH), biliary obstructions (e.g., biliary atresia), and metabolic causes (e.g., cystic fibrosis, alpha 1 antitrypsin deficiency).

12. GI Foreign Bodies Indications for Urgent Removal/Consultation (Patient Factors):

• Respiratory distress.
• Esophageal obstruction (inability to swallow).
• Intestinal obstruction or perforation.
• Esophageal impaction for more than 24 hours.

Indications for Urgent Removal/Consultation (Object Factors):

• Esophageal button battery.
• Sharp object in the stomach.
• Long object in the stomach (longer than 5 cm).
• Wide object in the stomach (wider than 2 cm).
• Multiple magnets.

13. Specific Pediatric GI Conditions Meckel's Diverticulum

• Presentation: Painless bleeding (hematochezia). Can lead to intussusception.
• Rule of Twos: Affects 2% of the population, located 2 feet proximal from the ileocecal valve, typically 2 inches in length, common in less than two-year-olds, and has a 2:1 male to female ratio.
• Management: Meckel scan, transfusion, possible surgery.

Midgut Volvulus with Malrotation

• Presentation: Presents in the first month of life with bilious vomiting in a sick infant.
• Diagnosis: Upper GI series with small bowel follow-through (may show corkscrew pattern or double bubble on X-ray).
• Management: Resuscitation, decompression, Antibiotics (Ampicillin, Gentamicin, Flagyl), and surgical consultation.

Necrotizing Enterocolitis (NEC)

• Presentation: Presents in the first month of life, particularly in premature babies. Onset related to starting enteral feeding.
• X-ray findings: Pneumatosis intestinalis, perforation, and dilated loops.
• Management: Decompression, resuscitation, Antibiotics (Ampicillin, Gentamicin, Flagyl), and surgical consultation.

Intussusception

• Common Age: 6 months to 2 years of age.
• Features: Colicky abdominal pain, current jelly stools, right-sided sausage-like mass, and lethargy between pain episodes.
• Diagnosis: Ultrasound shows a target sign.
• Management: Air or barium enema.

Hirschsprung's Enterocolitis

• Pathophysiology: Congenital lack of innervation of the myenteric plexus.
• Suspicion: Delayed meconium passage beyond one day.
• X-ray findings: Cut off sign in the colon, pneumatosis intestinalis, or signs of perforation.
• Management: Biopsy to confirm diagnosis. Enterocolitis treatment requires Ampicillin, Gentamicin, Flagyl, and pediatric surgery consultation.

Pyloric Stenosis

• Presentation: 3 weeks to 2 months of life. Features include projectile non-bilious emesis and a palpable olive-like mass.
• Labs: May show low potassium, low chloride, and alkalosis.
• Ultrasound Diagnostic Values (PI pneumonic): 3 mm by 14 mm by 19 mm (note: one source cites 4 mm instead of 3 mm).
• Management: Hydration, electrolyte correction, and surgical consultation (surgery is not urgent).

Henoch-Schönlein Purpura (HSP)

• Age: 4 to 6 year olds.
• Symptoms Mnemonic: ARENA: Abdominal pain, Rash (palpable purpura), Edema (diffuse), Nephritis, Arthritis.
• Key Lab Finding: Normal platelets despite the purpura.
• Treatment: NSAIDs. Steroids if severe abdominal pain, GI bleeding, hematuria, or severe arthritis. These severe findings also serve as admission criteria.

Disclaimer: Content is for educational exam preparation only and does not constitute medical advice. Medicine changes quickly; always verify with current, local guidelines before applying to patient care.