Renal Failure: CPB surgery

Clinical - Cardiovascular

After coronary revascularization, patients who develop ARF experience significant increases in both short- and long-term mortality. Mortality is far lower in patients with normal renal function (0.9 %) then in patients with accute renal failure (up to 60%).

Nonpulsatile flow and hypotension lead to renal vasoconstriction and decreased RBF. Norepinephrine and renin increase. High renin correlates c renal failure. Thromboxane from platelets also cause vasoconstriction. 2% of CPB patients will have ARF, if ARF occurs mortality is 60-80% . In normal kidney patients pulsatile vs non-pulsatile flow does not change ARF incidence . Pulsatile flow may be better for patients c CRI. ARF after CPB is more related to cardiac function after surgery than with mean pressures (even <50) while on CPB.

Risk factors

Risk factors for ARF following CPB include starting Cr 1.9 or higher , and combined/complex surgery .

Prophylactic Treatment

Dopamine does not improve renal outcome post CPB, and it may be harmful by increasing arrhythmias post-op. A metaanalysis of 13 RCTs including 1,059 patients suggested that fenoldopam (a D1 agonist) may reduce the risk of in-hospital death (OR 0.46, p = 0.002) and renal replacement therapy (OR 0.36, p < 0.001) as well as reducing ICU LOS by 0.93 days (p = 0.002).

Summary of Renal Dysfunction in CPB

  • 2% incidence (60-80% mortality when it occurs)
  • Risk factors include starting Cr 1.9 or higher, combined/complex surgery
  • Consider pulsatile flow for patients who already have CRI
  • Fenoldopam (but not dopamine) may reduce death, renal replacement therapy, and ICU stay.

Sources

    J Cardiothorac Vasc Anesth;2008 Feb;22(1):27-33

    [PubMed: 18249327]

    Circulation;2007 Sep 11;116(11 Suppl):I139-43

    [PubMed: 17846294]

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2012

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78%

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2009

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