🧪 Lecture 8
Lab Values & Five Deadly Ds
ABCD priority scheme, neutropenic precautions, Five Deadly Ds.
Priority Guide
⭐
ABCD Scheme: A=ignore a few hrs | B=monitor closely | C=critical, act now | D=highest, stay at bedside
| Lab | Normal | Priority Level |
|---|---|---|
| pH | 7.35–7.45 | Level D if pH in 6s |
| K+ | 3.5–5.3 | Level C if low/high | Level D if >6 |
| CO2 | 35–45 | Level C if 50s | Level D if 60s+ |
| O2/PaO2 | 78–100 | Level C if 70–77 | Level D if <60 |
| INR | 2–3 | Level C if ≥4 → hold Coumadin |
| Hgb | 12–18 | Level B if 8–11 | Level C if <8 |
| Platelets | 150k–450k | Level C if <90k | Level D if <40k |
| WBC | 4k–11k | Level C if <4k → neutropenic precautions |
| O2 Sat | 93–100% | Level C if <93 → give O2 now |
🚑 Five Deadly Ds — NEVER pit against each other
K+ >6 | pH in 6s | CO2 in 60s | pO2 <60 | Platelets <40,000
Neutropenic Precautions
✅
Strict hand washing | Vitals q4 hrs | Private room | Reverse isolation
✅
Shower BID with antimicrobial soap | Avoid crowds | Dedicated equipment
❌
No fresh flowers/plants | No raw fruits/veggies | No undercooked meat
❌
No water pitcher standing >15 min | No indwelling catheters | Check WBC daily
📖 Notes for Dummies
🧠 Think of it this way…
Lab values tell you how sick a patient is. The ABCD scheme is like a triage system for lab results — it tells you how urgently to respond. Don't memorize every number — just know the critical ones and what to DO.
🔴
Level D = "Drop everything and go!" — Five Deadly Ds:
K+ >6 (heart stops) | pH in 6s (severe acidosis) | CO2 in 60s (respiratory failure) | O2 <60 (not enough oxygen) | Platelets <40k (uncontrolled bleeding)
K+ >6 (heart stops) | pH in 6s (severe acidosis) | CO2 in 60s (respiratory failure) | O2 <60 (not enough oxygen) | Platelets <40k (uncontrolled bleeding)
🟡
Level C = "Act now but don't panic":
K+ just low or high (but not deadly yet), O2 sat below 93%, hemoglobin below 8, WBC below 4000
K+ just low or high (but not deadly yet), O2 sat below 93%, hemoglobin below 8, WBC below 4000
🟢
Level A & B = "Keep an eye on it":
Creatinine a bit off, BUN high, hemoglobin 8–11 — abnormal but not emergency
Creatinine a bit off, BUN high, hemoglobin 8–11 — abnormal but not emergency
📝 Easy memory tricks:
📉 Low K+? → assess heart (EKG) → give K+
📈 High K+? → hold K+, assess heart → insulin + Kayexalate
💉 Low O2 sat? → just give oxygen first, ask questions later
🩺 WBC low? → neutropenic precautions — protect them from every germ!
📉 Low K+? → assess heart (EKG) → give K+
📈 High K+? → hold K+, assess heart → insulin + Kayexalate
💉 Low O2 sat? → just give oxygen first, ask questions later
🩺 WBC low? → neutropenic precautions — protect them from every germ!