title: Early acid-base and blood pressure effects of continuous renal replacement therapy intensity in patients with metabolic acidosis.
abstract: OBJECTIVE
  In acute kidney injury patients, metabolic acidosis is common. Its severity, duration, and associated changes in mean arterial pressure (MAP) and vasopressor therapy may be affected by the intensity of continuous renal replacement therapy (CRRT). We aimed to compare key aspects of acidosis and MAP and vasopressor therapy in patients treated with two different CRRT intensities.
  
  
  METHODS
  We studied a nested cohort of 115 patients from two tertiary intensive care units (ICUs) within a large multicenter randomized controlled trial treated with lower intensity (LI) or higher intensity (HI) CRRT.
  
  
  RESULTS
  Levels of metabolic acidosis at randomization were similar [base excess (BE) of -8 ± 8 vs. -8 ± 7 mEq/l; p = 0.76]. Speed of BE correction did not differ between the two groups. However, the HI group had a greater increase in MAP from baseline to 24 h (7 ± 3 vs. 0 ± 3 mmHg; p < 0.01) and a greater decrease in norepinephrine dose (from 12.5 to 3.5 vs. 5 to 2.5 μg/min; p < 0.05). The correlation (r) coefficients between absolute change in MAP and norepinephrine (NE) dose versus change in BE were 0.05 and -0.37, respectively.
  
  
  CONCLUSIONS
  Overall, LI and HI CRRT have similar acid-base effects in patients with acidosis. However, HI was associated with greater improvements in MAP and vasopressor requirements (clinical trial no. NCT00221013).
authors.affiliation: ANZICS CTG, Level 3, 10 Ievers St, Carlton, VIC 3053, Australia. rinaldo.bellomo@austin.org.au
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.forename: Miklos
authors.initials: M
authors.lastname: Lipcsey
authors.forename: Paolo
authors.initials: P
authors.lastname: Calzavacca
authors.forename: Michael
authors.initials: M
authors.lastname: Haase
authors.forename: Anjia
authors.initials: A
authors.lastname: Haase-Fielitz
authors.forename: Elisa
authors.initials: E
authors.lastname: Licari
authors.forename: Augustine
authors.initials: A
authors.lastname: Tee
authors.forename: Louise
authors.initials: L
authors.lastname: Cole
authors.forename: Alan
authors.initials: A
authors.lastname: Cass
authors.forename: Simon
authors.initials: S
authors.lastname: Finfer
authors.forename: Martin
authors.initials: M
authors.lastname: Gallagher
authors.forename: Joanne
authors.initials: J
authors.lastname: Lee
authors.forename: Serigne
authors.initials: S
authors.lastname: Lo
authors.forename: Colin
authors.initials: C
authors.lastname: McArthur
authors.forename: Shay
authors.initials: S
authors.lastname: McGuinness
authors.forename: John
authors.initials: J
authors.lastname: Myburgh
authors.forename: Carlos
authors.initials: C
authors.lastname: Scheinkestel
mesh_terms: D000137:Acid-Base Imbalance; D000138:Acidosis / Q000150:complications* / Q000503:physiopathology; D058186:Acute Kidney Injury / Q000150:complications* / Q000503:physiopathology / Q000628:therapy*; D000368:Aged; D001794:Blood Pressure; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D017582:Renal Replacement Therapy / Q000379:methods*