Hemodynamics
Cerebral Perfusion Pressure (CPP) Calculator
MAP minus ICP, the pressure that drives blood through the brain; the number to protect after traumatic brain injury.
Formula
CPP = MAP - ICP
Reference: TBI target 60–70 mm Hg
How it is used
- Goal CPP in traumatic brain injury (TBI) is 60–70 mm Hg (Brain Trauma Foundation).
- Low CPP causes ischemia; avoid pushing CPP above 70 with fluids and vasopressors, which raised the risk of ARDS.
- Intact autoregulation holds cerebral flow steady across a CPP of roughly 50–150 mm Hg; after TBI, SAH or ICH it often fails and flow follows pressure.
Key points
- Treat elevated ICP with hyperosmolar therapy (mannitol, hypertonic saline), sedation, or CSF drainage before aggressively pushing MAP with vasopressors.
Related one-pagers
- Neuro: ICP and StrokeCPP · MAP − ICP
- ACLS Algorithms in BriefCPP is aortic minus right atrial diastolic pressure; no patient reached ROSC below 15 mm Hg (Paradis 1990).
- Pediatric Assessment and EmergenciesPECARN (Kuppermann 2009) for minor head trauma under age 2: GCS 14, other altered mentation or a palpable skull fracture means CT (4.4% risk of important brain injury); a nonfrontal scalp hematoma, loss of consciousness of 5 seconds or more, a severe mechanism or not acting normally allows observation or CT (0.9%); none of these means no CT (under 0.02%). In severe TBI the Brain Trauma Foundation (2019) treats ICP over 20 mm Hg, keeps CPP at least 40, gives 3% saline 2–5 mL/kg and avoids PaCO₂ below 30 in the first 48 hours.
- Hemodynamic Normals
Related calculators
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- Mean Arterial Pressure (MAP)
- Oxygen Delivery (DO₂)
- Pulmonary Vascular Resistance (PVR)
- QTc (Bazett)
- Shock Index
- Stroke Volume (SV)
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For education and exam preparation only. Follow your institution’s protocols. For education and exam preparation only. Verify results independently and follow your local protocols and medical direction. Not a substitute for clinical judgment.