Pulse contour cardiac output analysis in a piglet model of severe hemorrhagic shock.
OBJECTIVE
Pulse contour cardiac output (PCCO) analysis is a technique for continuous cardiac output (CO) monitoring through an arterial catheter after calibration by transpulmonary thermodilution (TPTD). Studies in adults show good correlation with pulmonary artery thermodilution (PATD) CO. Data are limited in children and patients with hemodynamic instability. The objective was to determine whether TPTD CO and PCCO analysis correlate with PATD CO in a piglet model of severe hemorrhagic shock. Mixed venous oxygen saturation (SVO2) was also compared with PATD CO.


METHODS
Prospective animal study.


METHODS
University animal research laboratory.


METHODS
Domesticated piglets, 24-37 kg.


METHODS
Hemorrhagic shock was created by graded hemorrhage in anesthetized piglets. Hemorrhage was initiated to achieve mean arterial pressure plateaus of 60, 50, 40, 30, and 20 mm Hg.


RESULTS
CO was measured by PATD and simultaneously with two femoral artery PCCO catheters. At each mean arterial pressure plateau, one PCCO catheter was recalibrated by TPTD; the other catheter was not recalibrated during hemorrhage. TPTD CO, PCCO measurements from each catheter, and SVO2 were compared with PATD CO at each mean arterial pressure level. TPTD CO and recalibrated PCCO showed excellent correlation (r2 = .96 and .97) and small bias (+0.11 and +0.14 L/min), respectively, compared with PATD. Without recalibration, PCCO measurements were not accurate during rapid hemorrhage (r2 = .22). SVO2 decline did not correlate as well with PATD CO (r2 = .69).


CONCLUSIONS
TPTD CO and recalibrated PCCO analysis correlate well with PATD CO in this severe hemorrhagic shock model. The mean difference is small (<0.15 L/min) and is not clinically significant. With rapid changes in blood pressure or intravascular volume, PCCO is not accurate unless recalibrated by TPTD CO. SVO2 did not correlate well with CO in this model.
Piehl
Mark D
MD
Division of Pediatric Critical Care, WakeMed Health and Hospitals, Raleigh, NC, USA. mpiehl@wakemed.org
Manning
James E
JE
McCurdy
Shane L
SL
Rhue
Tim S
TS
Kocis
Keith C
KC
Cairns
Charles B
CB
Cairns
Bruce A
BA
D000818:Animals; D001794:Blood Pressure; D002302:Cardiac Output; D004195:Disease Models, Animal; D016014:Linear Models; D008991:Monitoring, Physiologic / Q000379:methods*; D011674:Pulse; D012771:Shock, Hemorrhagic / Q000503:physiopathology*; D013552:Swine; D013815:Thermodilution / Q000379:methods