title: Cardiac output with CO2 rebreathing method in CAPD patients.
abstract: The aim of this study is to evaluate cardiac output (CO) with CO2 rebreathing method (RCO2) in patients (pts) on CAPD. We have studied 15 pts on CAPD from at least 6 months, the mean (+/- SD) age was 55 +/- 4 years, mean (+/- SD) hemoglobin was 10 +/- 2 gr/dl. The respiratory tests excluded obstructive or restrictive broncopneumopathies. Electrocardiograms and B-mode echocardiograms were normal. RCO2 was evaluated using the FICK formula: CO = VCO2/CvCO2 - CaCO2 where VCO2 is CO2 production; CvCO2 is the CO2 content in venous mixed blood; CACO2 is arterial CO2. VCO2 was obtained by collecting expired air into a Douglas bag during respiration at rest for 4 minutes. CvCO2 was obtained after 10-15 seconds of respiration in a mixture of 7% CO2 in O2. CaCO2 was obtained at CO2 end-tidal capnogram. RCO2 was performed in CAPD with full and empty abdomen. The mean (+/- SD) CO was 2.3 +/- 1.04 l/min with both full and empty abdomen, values below those theoretically calculated, taking into account the age and body surface (4.7 +/- 0.6 l/min P less than 0.0005). The reduction of CO is not induced by left ventricular insufficiency, but such phenomenon could be attributed to a redistribution of body fluid between intra and extracellular, in favour of the intracellular compartment. Therefore the increase in hematocrit and total plasma proteins can be fictitious.
authors.affiliation: Renal Unit, L. Sacco Hospital, Milan, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Bertoli
authors.forename: D
authors.initials: D
authors.lastname: Scorza
authors.forename: A
authors.initials: A
authors.lastname: Genderini
authors.forename: M T
authors.initials: MT
authors.lastname: Barone
authors.forename: S
authors.initials: S
authors.lastname: Milani
authors.forename: M
authors.initials: M
authors.lastname: Sergi
authors.forename: M
authors.initials: M
authors.lastname: Rizzi
authors.forename: E
authors.initials: E
authors.lastname: Bosisio
authors.forename: G B
authors.initials: GB
authors.lastname: Di Belgiojoso
mesh_terms: D000368:Aged; D000403:Airway Resistance; D002245:Carbon Dioxide / Q000502:physiology*; D002302:Cardiac Output; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory; D012129:Respiratory Function Tests; D014109:Total Lung Capacity; D014797:Vital Capacity
chemical_list: D002245:Carbon Dioxide