NORMAL ICU HEMODYNAMIC VALUES

1. Cardiac Output (CO)

• Normal: 4 – 8 L/min

CO = HR × Stroke Volume
Higher in sepsis; lower in cardiogenic shock.

---

2. Cardiac Index (CI)

• Normal: 2.5 – 4.0 L/min/m²

• Shock definition: CI < 2.2 (cardiogenic shock)

CI adjusts CO for body size → more accurate measure of perfusion.

---

3. Central Venous Pressure (CVP)

• Normal: 2 – 8 mmHg

  • < 2 = hypovolemia

  • 12 = volume overload / RV strain

  • Not reliable alone—use ultrasound + clinical exam.

---

4. Mean Arterial Pressure (MAP)

• Normal goal: ≥ 65 mmHg in ICU
  Lower MAP tolerated in some chronic HTN patients or young healthy individuals.

---

5. Pulmonary Artery Pressures (if Swan catheter)

Pulmonary Artery Pressure (PAP)

• Normal: 15–30 / 8–15 mmHg

  • Systolic: 15–30

  • Diastolic: 8–15

Mean PAP (mPAP)

• Normal: 10–20 mmHg

• Pulmonary hypertension: mPAP > 20 mmHg

---

6. Pulmonary Capillary Wedge Pressure (PCWP)

• Normal: 6 – 12 mmHg

• > 18 mmHg → pulmonary edema, left-sided heart failure

• < 5 mmHg → hypovolemia

---

7. Systemic Vascular Resistance (SVR)

• Normal: 800 – 1200 dyn·s/cm⁵

• Low SVR: septic shock, anaphylaxis

• High SVR: cardiogenic shock, hypovolemia

SVR = (MAP − CVP) / CO × 80

---

8. Pulmonary Vascular Resistance (PVR)

• Normal: 20 – 130 dyn·s/cm⁵
  Elevated in:

• ARDS

• Pulmonary hypertension

• PE

• RV failure

---

9. Mixed Venous Oxygen Saturation (SvO₂)

• Normal: 60–80%

• Low SvO₂ → low CO, anemia, or high O₂ extraction (shock)

• High SvO₂ → sepsis, shunting, or mitochondrial dysfunction

---

10. Central Venous O2 Saturation (ScvO₂)

• Normal: 70–80%

• ScvO₂ < 70% → inadequate oxygen delivery (shock)

---

Quick ICU Hemodynamics Cheat-Sheet (What they mean)

Parameter	Low Value Suggests	High Value Suggests
CO / CI	cardiogenic shock, hypovolemia	sepsis, anemia, hyperdynamic
CVP	hypovolemia, vasodilation	RV failure, overload
PCWP	hypovolemia	LV failure, pulmonary edema
SVR	sepsis, anaphylaxis	shock states (cardio, hypo), vasoconstriction
SvO₂	low CO, increased extraction	sepsis, shunt
PVR	PE, ARDS	pulmonary HTN

 

***ICU Pearls

• CI is more important than CO for shock diagnosis.

• CVP is not reliable alone—use ultrasound (IVC, RV function).

• SvO₂ < 60% = bad; think shock, low CO.

• SVR low = septic; SVR high = cardiogenic/hypovolemic.

• PCWP helps separate ARDS vs cardiogenic pulmonary edema.