Emergency Medicine & Vital Signs – Notes

Why EM?

• Internal medicine → EM shift: desire for immediacy, impact, fast connection with patients. 

• EM requires quick thinking, decision-making with incomplete info, constant adjustment.

• Love of detective work + adrenaline.

Approach to Vital Signs

• "Vital" = life. Numbers are not trivial.

• Common error: ignoring abnormal values (e.g., dismissing as error).

• Always review vital signs before discharge → missed case: trauma patient with puncture → delayed hemothorax, nearly collapsed on discharge.

Terminology

• Avoid “vital signs stable” → even death = most stable (0-0-0-0).

• Use “vital signs normal.”

Temperature

• Fever: >100.4–100.6 °F.

• Oral temp unreliable (ice, hot drinks, etc.).

• Axillary = not useful; tympanic unreliable (cerumen, canal anatomy).

• Best core measure: rectal temperature.

• Trust your exam (feel patient’s skin) > chart.

• Mnemonic: TIME for fever causes:

  • Toxic (e.g., serotonin syndrome, salicylates)

  • Infection

  • Metabolic (e.g., thyroid disease)

  • Environmental (heat stroke)

Treatment:

• Acetaminophen, ibuprofen, NSAIDs. Dose accurately.

Blood Pressure

• White coat HTN, anxiety, stress = possible. Recheck after time.

• Don’t diagnose HTN on a single ED measurement.

• Measurement errors:

  • Position (arm not at heart level).

  • Wrong cuff size (too small = falsely high, too big = falsely low).

• Don’t attribute high BP to pain/stress without checking trends.

• Headache + HTN: address separately; don’t assume causal link.

• Don’t aggressively normalize chronic high BP in ED → harm risk.

• Low BP: shock ≠ just hypotension. It = inadequate oxygen delivery.

  • Compensated vs. uncompensated shock.

  • Shock index = HR / SBP → should be <0.9.

Heart Rate

• Normal: 60–100 (better: 60–90).

• Tachy >90 in healthy adult = concerning.

• Brady in shock = preterminal.

• Always check pulse quality (strong/thready, regular/irregular).

• Pulse locations & systolic estimates:

  • Radial = ~90

  • Femoral = ~60

  • Carotid = ~40

Respiratory Rate

• Often falsely recorded as “20.”

• Observe >15 seconds; ideally 30–60 seconds.

• Look for work of breathing, depth, retractions, pattern.

• Example: rising RR trend → clue to salicylate poisoning.

• RR is an early sensitive marker → don’t ignore.

Orthostatic Vital Signs

• Unreliable, high false positives/negatives.

• Symptoms trump numbers (e.g., dizziness on standing = positive).

• No universal standard for measurement/cutoffs.

• Study: even healthy residents had varied responses to blood loss.

Pulse Oximetry

• True “5th vital sign.”

• O₂ sat ≥92% = good plateau.

• 90% sat = PaO₂ ~60 → below this, small drops = big PaO₂ decreases.

• Low sats are usually real (COVID-19 example: “happy hypoxemia”).

• Consider skin tone, nail polish, probe issues, but trust unless clear artifact.

Pediatric Vital Signs

• Vary by age.

• Newborn: systolic BP ≥70, RR up to 60 normal.

• Use apps or Broselow tape for quick reference.

• Don’t memorize; numbers shift quickly with growth.

Key Takeaways

• Vital signs are truly vital.

• Don’t dismiss abnormal values as errors.

• Interpret vitals in context with clinical exam.

• Use mnemonics (e.g., TIME).

• Always recheck, confirm, and document carefully.