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Cerebral blood flow is proportional to cardiac index in patients with septic shock

S M Smith1, S Padayachee, K B Modaresi

  • 1Department of Intensive Care, Guy's Hospital, London, England.

Journal of Critical Care
|October 3, 1998
PubMed

Insights

Septic shock disrupts normal blood flow regulation. In septic shock patients, cerebral blood flow is linked to cardiac index, unlike in healthy individuals, indicating a loss of autoregulation.

Area of Science:

  • Cardiovascular Physiology
  • Critical Care Medicine
  • Neuroscience

Background:

  • Septic shock often presents with an increased cardiac index.
  • Regional hypoperfusion and blood flow maldistribution are key in septic shock-induced organ dysfunction.

Purpose of the Study:

  • To investigate the relationship between cerebral blood flow and cardiac index in septic shock patients.
  • To understand alterations in limb and cerebral blood flow regulation during septic shock.

Main Methods:

  • Doppler ultrasound was employed to measure limb and carotid blood flow.
  • 15 patients with septic shock and 9 nonseptic controls were studied.

Main Results:

  • Nonseptic controls showed proportional limb blood flow to cardiac index, indicating protective flow redistribution.
  • Septic shock patients lacked this limb blood flow-cardiac index relationship.
  • Cerebral blood flow was correlated with cardiac index in septic shock patients, but not controls.

Conclusions:

  • Data suggest a loss of cerebral blood flow autoregulation in human septic shock.
  • Changes in the control of limb blood flow were observed in septic shock.
Abstract

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