title: Does aggressive hydration reverse the effects of pneumoperitoneum on renal perfusion?
abstract: BACKGROUND
  Although pneumoperitoneum (PP) decreases renal blood flow, it remains unclear whether this impacts renal function. Our aim was to characterize the effects of PP on renal perfusion and function using two fluid strategies for intravenous fluid administration.
  
  
  METHODS
  Twelve 30-kg pigs were randomized into two groups: maintenance (3 cc/kg/h of normal saline (NS)) and bolus (15 cc/kg/h + 20 cc/kg NaCl bolus prior to induction of PP). Pigs were studied in a blinded fashion for 30 min prior, 60 min during, and 30 min after release of 15 mmHg CO(2) PP. Cardiac output (CO) and stroke volume (SV) were measured using an esophageal Doppler probe, renal cortical perfusion (RCP) was measured with a laser Doppler probe on the right kidney, and renal function was measured using the fractional excretion of sodium (FeNa) and urine output. Statistical analysis was performed with area-under-the-curve (AUC) analysis and analysis of variance
  
  
  RESULTS
  AUC analysis revealed moderate effect size for CO (0.416) and small effect size for SV (0.366) and RCP (0.363), with decreases seen in the control group but not the bolus group. During PP, urine output increased in the bolus group (p = 0.04) but not in the control group; there was no difference in FeNa in either group.
  
  
  CONCLUSIONS
  Aggressive fluid hydration during CO(2) PP of 15 mmHg preserves CO, SV, and RCP while increasing urine output. No effect on renal function as measured by FeNa was observed in either group.
authors.affiliation: Steinberg-Bernstein Centre for Minimally Invasive Surgery, McGill University, 1650 Cedar Avenue, Room L9-316, Montreal, Quebec, H3G 1A4, Canada.
authors.forename: S V
authors.initials: SV
authors.lastname: Demyttenaere
authors.forename: L S
authors.initials: LS
authors.lastname: Feldman
authors.forename: S
authors.initials: S
authors.lastname: Bergman
authors.forename: S
authors.initials: S
authors.lastname: Gholoum
authors.forename: C
authors.initials: C
authors.lastname: Moriello
authors.forename: B
authors.initials: B
authors.lastname: Unikowsky
authors.forename: S
authors.initials: S
authors.lastname: Fraser
authors.forename: F
authors.initials: F
authors.lastname: Carli
authors.forename: G M
authors.initials: GM
authors.lastname: Fried
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000008:administration & dosage; D004231:Diuresis; D004305:Dose-Response Relationship, Drug; D005440:Fluid Therapy / Q000379:methods; D007275:Injections, Intravenous; D007668:Kidney / Q000503:physiopathology*; D007672:Kidney Cortex / Q000098:blood supply; D007674:Kidney Diseases / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy*; D009318:Natriuresis; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects*; D012079:Renal Circulation; D012965:Sodium Chloride / Q000008:administration & dosage / Q000627:therapeutic use; D013318:Stroke Volume; D013552:Swine
chemical_list: D002245:Carbon Dioxide; D012965:Sodium Chloride