title: Effect of increased renal venous pressure on renal function.
abstract: OBJECTIVE
  Acute renal failure is seen with the acute abdominal compartment syndrome (AACS). Although the cause of acute renal failure in AACS may be multifactorial, renal vein compression alone has not been investigated. This study evaluated the effects of elevated renal vein pressure (RVP) on renal function.
  
  
  METHODS
  Two groups of swine (18-22 kg) were studied after left nephrectomy and placement of a renal artery flow probe to measure renal artery blood flow, renal vein catheter, and ureteral cannula. Two hours were allowed for equilibration and an inulin infusion was begun to calculate inulin clearance for measurement of glomerular filtration rate. Group 1 animals (n = 4) had RVP elevated by 30 mm Hg for 2 hours with renal vein constriction. RVP was then returned to baseline for 1 hour. In group 2 (n = 4), the RVP was not elevated. The cardiac index (2.9 +/- 0.5 L/min/m2) and mean arterial pressure (101 +/- 9 mm Hg) remained stable. Plasma renin activity and serum aldosterone were measured every 60 minutes.
  
  
  RESULTS
  Elevation of RVP (0-30 mm Hg above baseline) in the experimental group showed a significant decrease in renal artery blood flow index (2.7 to 1.5 mL/min per g) and glomerular filtration rate (26 to 8 mL/min) compared with control. In addition, there was significant elevation of plasma serum aldosterone (14 to 25 microng/dL) and plasma renin activity (2.6 to 9.5 microng/mL per h) as well as urinary protein leak in the experimental animals compared with control. These changes were partially or completely reversible as RVP returned toward baseline.
  
  
  CONCLUSIONS
  Elevated RVP alone leads to decreased renal artery blood flow and glomerular filtration rate and increased plasma renin activity, serum aldosterone, and urinary protein leak. These changes are consistent with the renal pathophysiology seen in AACS, morbid obesity, and preeclampsia. The changes are partially or completely reversed by decreasing renal venous pressure as occurs with abdominal decompression for AACS.
authors.affiliation: Department of Surgery, Medical College of Virginia of Virginia Commonwealth University, Richmond, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Doty
authors.forename: B H
authors.initials: BH
authors.lastname: Saggi
authors.forename: H J
authors.initials: HJ
authors.lastname: Sugerman
authors.forename: C R
authors.initials: CR
authors.lastname: Blocher
authors.forename: R
authors.initials: R
authors.lastname: Pin
authors.forename: I
authors.initials: I
authors.lastname: Fakhry
authors.forename: T W
authors.initials: TW
authors.lastname: Gehr
authors.forename: D A
authors.initials: DA
authors.lastname: Sica
mesh_terms: D000005:Abdomen / Q000098:blood supply*; D000208:Acute Disease; D058186:Acute Kidney Injury / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology*; D000450:Aldosterone / Q000097:blood; D000818:Animals; D001783:Blood Flow Velocity; D003161:Compartment Syndromes / Q000150:complications*; D004195:Disease Models, Animal; D005919:Glomerular Filtration Rate; D007444:Inulin / Q000493:pharmacokinetics; D011507:Proteinuria / Q000209:etiology / Q000652:urine; D012077:Renal Artery / Q000503:physiopathology*; D012079:Renal Circulation; D012083:Renin / Q000097:blood; D013552:Swine; D014563:Urodynamics; D014655:Vascular Resistance; D014690:Venous Pressure
chemical_list: D000450:Aldosterone; D007444:Inulin; D012083:Renin