Comparison of noninvasive cardiac output monitor (NICOM, Cheetah Medical) with Edwards FloTrac minimally-invasive cardiac output monitor in predicting fluid responsiveness in sepsis and septic shock.

Study will evaluate ability of passive leg raise test to predict fluid responsiveness in patients in septic shock, on vasopressors, using both the NICOM and FloTrac devices. An increase in CI, SVI, or Pulse Pressure of >10% in response to the passive leg raise will be considered a positive passive leg raise test, and the same indicators will be considered a significant response to a fluid challenge with either crystalloids or colloids.Each device will be evaluated independently, but simultaneously.

Inclusion Criteria:

• All adult patients with severe sepsis or septic shock, who have arterial catheter placed with FloTrac monitor, with or without a central venous catheter.

Exclusion Criteria:

• Declination of consent
• Known allergy to adhesive
• Pregnancy
• Contraindication to raising legs or head to 45 degrees for 3 minute intervals