title: Venous hypercarbia associated with severe sepsis and systemic hypoperfusion.
abstract: We studied 37 patients with severe sepsis and systemic hypoperfusion to assess changes in PvCO2. Before fluid administration, the cardiac index (CI) was 2.64 +/- 0.14 L/min.m2. The PvCO2 was 38 +/- 1 torr and mixed venous pH was 7.32 +/- 0.02. The venous-arterial CO2 tension gradient (P[v-a]CO2) was 6 +/- 1 torr. After fluid administration, the CI increased to 3.45 +/- 0.14 L/min.m2 (p less than .001) and the P(v-a)CO2 decreased to 5 +/- 1 torr. The correlation between the change in CI and the change in P(v-a)CO2 was r = .42, p less than .01. P(v-a)CO2 was elevated in 19 (51%) patients before fluid administration (P[v-a]CO2 greater than 6 torr) (hypercarbic group). The P(v-a)CO2 gradient in this group was 9 +/- 1 compared with 4 +/- 1 torr in 18 patients with a normal P(v-a)CO2 gradient (p less than .001) (normocarbic group). PvCO2 was 41 +/- 2 torr in the hypercarbic group compared with 35 +/- 2 torr in the normocarbic group (p less than .05). No difference was noted in PaCO2. Venous arterial pH and HCO3- gradients were of greater magnitude in the hypercarbic group, -0.05 +/- 0.003 and 2.4 +/- 0.3 mEq/L compared to -0.02 +/- 0.004 (p less than .001) and 1.1 +/- 0.2 mEq/L (p less than .001), respectively. CI in the hypercarbic group was 2.3 +/- 0.2 compared to 3.0 +/- 0.2 L/min.m2 in the normocarbic group (p less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Medicine, University of Health Sciences/Chicago Medical School, IL.
authors.forename: C E
authors.initials: CE
authors.lastname: Mecher
authors.forename: E C
authors.initials: EC
authors.lastname: Rackow
authors.forename: M E
authors.initials: ME
authors.lastname: Astiz
authors.forename: M H
authors.initials: MH
authors.lastname: Weil
mesh_terms: D000136:Acid-Base Equilibrium; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001639:Bicarbonates / Q000097:blood; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D005440:Fluid Therapy; D006439:Hemodynamics; D006801:Humans; D006935:Hypercapnia / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D012772:Shock, Septic / Q000097:blood / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D014680:Veins
chemical_list: D001639:Bicarbonates; D007773:Lactates; D002245:Carbon Dioxide; D010100:Oxygen