Systolic pressure variation predicts the response to acute blood loss.
OBJECTIVE
To evaluate systolic pressure variation (SPV), defined as the difference between the maximum and minimum systolic blood pressure measured during a controlled mechanical respiratory cycle, as a predictor of the cardiac output (CO) response to an acute decrease in ventricular preload.


METHODS
Prospective study with each subject serving as his or her own control.


METHODS
Cardiac surgery operating rooms of a university medical center.


METHODS
15 adults with good ventricular function undergoing coronary artery bypass grafting.


METHODS
During stable anesthetic conditions and before surgical stimulation, 500 ml of blood was removed from each patient over 10 minutes.


RESULTS
CO, central venous pressure (CVP), pulmonary artery diastolic pressure, and pulmonary artery occlusion pressure (PAOP), and SPV before and after phlebotomy were recorded. Phlebotomy was associated with significant decreases in CVP, PAOP, and CO, and an increase in SPV. Of these variables, SPV was the best predictor of the percent decrease in CO resulting from blood loss.


CONCLUSIONS
SPV is a dynamic measurement, which, by revealing the response to small cyclical changes in left ventricular preload that occur during the controlled mechanical respiratory cycle, is a better predictor than central filling pressures of the response of CO to acute decreases in preload that occur as a result of acute blood loss.
Ornstein
E
E
Department of Anesthesiology/Critical Care Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
Eidelman
L A
LA
Drenger
B
B
Elami
A
A
Pizov
R
R
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016063:Blood Loss, Surgical / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D002302:Cardiac Output / Q000502:physiology; D001026:Coronary Artery Bypass; D006801:Humans; D008875:Middle Aged; D018962:Phlebotomy; D011446:Prospective Studies; D013599:Systole / Q000502:physiology; D014700:Verapamil / Q000627:therapeutic use
D002121:Calcium Channel Blockers; D014700:Verapamil