Cerebral Perfusion Pressure (CPP)

(Hamby, 2017; Mount & Das, 2021; Popovich, 2011)

What is CPP?

  • CPP is the net pressure gradient driving oxygen delivery to the brain. It is the difference between MAP and ICP, calculated with the formula: CPP = MAP - ICP. Normal range is 60-80 mm Hg. CPP should be kept at more than 60 mmHg for best outcomes. This is typically associated with TBI, but can occasionally be measured after a CVA, especially hemorrhagic. 

CPP Ranges

  • 60-65 mm Hg: ideal level; Therapy can proceed as normal

  • 50-59 & 65-70 mm Hg: Therapy can be performed, but limited to light activity. Be sure to discuss with the RN and/or medical team. Keeping the head of bed elevated to at least 30 degrees can help to maintain CPP

  • <50 or > 70 mm Hg: defer therapy

Why Do We Care?

  • Low CPP can result in further ischemic damage. CPP of < 50 mmHg is associated with poor outcomes in TBI and < 30 indicates a poor prognosis, resulting in irreversible neuronal hypoxia.

References

Hamby, J. (2017). The Nervous System. In H. Smith-Gabai & S. E. Holm (Eds.), Occupational Therapy in Acute Care (2nd ed.). AOTA Press.

Mount, C. A., & Das, J. M. (2021). Cerebral Perfusion Pressure. In StatPearls [Internet]. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK537271/

Popovich, K. (2011). The Intensive Care Unit. In H. Smith-Gabai (Ed.), Occupational Therapy in Acute Care (1st ed., pp. 41–73). AOTA Press.