title: Comparison between intermittent and continuous measurement of cardiac output after acute normovolemic hemodilution in pigs.
abstract: Continuous cardiac output (CO) and mixed venous oxygen saturation (SvO2) determined through the pulmonary artery catheter may be helpful in monitoring hemodynamic conditions in critically ill patients. This study aimed to evaluate CO and SvO2 in a model of acute normovolemic hemodilution (ANH), analyzing the accuracy of the continuous versus intermittent method for CO and SvO2 measurement in pigs. Twenty-three pigs were enrolled to three groups: control, ANH with 6% hydroxyethyl starch (HES), or ANH with lactated Ringer's (LR) solution. After hemodilution, we showed that SvO2 was reduced in both groups, mainly in LR animals (P < 0.05). Regarding the evaluation of CO, we showed an increase in both groups submitted to ANH (P < 0.05). Through Bland-Altman analysis, we showed that the continuous CO catheter presented lower values than the intermittent method after hemodilution, mainly with HES (P < 0.001), and there was no difference in the measurement of SvO2. The ANH promoted a decrease in SvO2 and an increase in CO values, mainly in animals submitted to hemodilution with HES. The use of continuous and intermittent (laboratory) measurement of SvO2 showed clinical applicability and good agreement, an effect not reproduced by the CO measurement. New studies are needed to further investigate the agreement between the continuous and intermittent methods for the measurement of CO in adverse hemodynamic conditions such as ANH.
authors.affiliation: Department of Anesthesia (LIMOS), University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: Denise A
authors.initials: DA
authors.lastname: Otsuki
authors.forename: Fernando A
authors.initials: FA
authors.lastname: Cardieri
authors.forename: André P
authors.initials: AP
authors.lastname: Schmidt
authors.forename: Marcio
authors.initials: M
authors.lastname: Brudniewski
authors.forename: Denise T
authors.initials: DT
authors.lastname: Fantoni
authors.forename: José O C
authors.initials: JO
authors.lastname: Auler
mesh_terms: D000818:Animals; D001794:Blood Pressure; D002302:Cardiac Output; D002407:Catheterization, Swan-Ganz; D005260:Female; D006438:Hemodilution / Q000379:methods*; D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D010092:Oximetry / Q000379:methods*; D010952:Plasma Substitutes; D000077325:Ringer's Lactate; D013552:Swine
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D010952:Plasma Substitutes; D000077325:Ringer's Lactate