A Randomized Trial of Pulsatile Perfusion Using an Intra-Aortic Balloon Pump Versus Nonpulsatile Perfusion on Short-Term Changes in Kidney Function During Cardiopulmonary Bypass During Myocardial Reperfusion
Received 29 December 2006; accepted 23 May 2007.
Background
Nonpulsatile perfusion during cardiopulmonary bypass can induce renal damage. We evaluated whether pulsatile perfusion using an intra-aortic balloon pump preserves renal function in patients undergoing myocardial revascularization.
100 patients undergoing preoperative perfusion using an intra-aortic balloon pump; 64 with baseline estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73 m2 or greater (≥1 mL/s/1.73 m2; stage 1 or 2) and 36 with eGFR of 30 to 59 mL/min/1.73 m2 (0.5 to 0.98 mL/s/1.73 m2; stage 3).
Intervention
Patients were randomly assigned to nonpulsatile perfusion during cardiopulmonary bypass (group A) or automatic intra-aortic balloon pump–induced pulsatile perfusion during cardiopulmonary bypass (group B).
Outcomes & Measurements
Renal function, daily diuresis, complications, serum lactate levels, and other biochemical indices at 24 and 48 hours.
Results
GFR, adjusted for baseline eGFR, was 16 mL/min/1.73 m2 [0.27 mL/s/1.73 m2] less in group A (58.1 mL/min/1.73 m2; 95% confidence interval [CI], 56.1 to 60.1 mL/min/1.73 m2 [0.97 mL/s/1.73 m2; 95% CI, 0.94 to 1.0 mL/s/1.73 m2]) than in group B (74.0 mL/min/1.73 m2; 95% CI, 72.0 to 76.1 mL/min/1.73 m2 [1.23 mL/s/1.73 m2; 95% CI, 1.20 to 1.27 mL/s/1.73 m2]; P < 0.001). Plasma lactate levels were +3.9 mg/dL (+0.43 mmol/L) higher in group A (19.5 mg/dL; 95% CI, 18.4 to 20.5 mg/dL [2.16 mmol/L; 95% CI, 2.04 to 2.28 mmol/L]) than in group B (16.7 mg/dL; 95% CI, 14.4 to 16.7 mg/dL [1.73 mmol/L; 95% CI, 1.60 to 1.85 mmol/L]; P < 0.001). No significant difference between the 2 groups was observed for 24-hour diuresis. Patients with eGFR stage 3 had a greater decrease in GFR and daily diuresis and greater increase in lactate levels than those with eGFR stages 1 to 2.
Limitations
Short-term change in kidney function as a surrogate outcome for “hard” clinical outcomes of mortality, morbidity, and length of hospitalization. Other limitations are short-term follow-up and absence of measurement of hemodynamic parameters or inflammatory mediators.
Conclusions
Use of automatic pulsatile intra-aortic balloon pumps during cardiopulmonary bypass is associated with better renal function during myocardial reperfusion. More studies are needed to verify the effects of pulsatile intra-aortic balloon pumps.
1Cardiac Surgery Unit, Magna Graecia University, Catanzaro, Italy
2Nephrology Unit, Magna Graecia University, Catanzaro, Italy.
Address correspondence to Giorgio Fuiano, MD, Professor of Nephrology, Cattedra di Nefrologia, Facoltà di Medicina, Campus Germaneto, Viale Europa 88100 Catanzaro, Italy.
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