Objective: The growing life expectancy has led the elderly to be increasingly referred to coronary artery bypass grafting. Preexisting comorbidities may benefit from theoretical advantages of pulsatile perfusion during cardiopulmonary bypass (CPB).
Design: Prospective randomized trial.
Setting: Cardiac surgery unit in a university hospital.
Patients: Eighty consecutive patients older than 70 years.
Interventions: Elective coronary artery bypass grafting on CPB, randomizing to conventional linear CPB (40 patients, group A) or intra-aortic balloon pump (IABP)-induced pulsatile CPB (40 patients, group B).
Measurements and main results: We evaluated hemodynamic response by pulmonary artery flotation catheter, metabolic/splanchnic response by lactate and transaminase, bilirubin, amylase, and renal function (creatinine clearance, creatinine, incidence of renal insufficiency and failure), respiratory response by Pao2/Fio2, respiratory compliance, scoring of chest radiograph, intubation time, and need for noninvasive positive-pressure ventilation, hematologic response by chest drainage, hemocoagulative and fibrinolytic cascades, and transfusions. IABP-related complications were recorded. Two minor IABP-related complications (2.5%) were registered. Hemodynamics was comparable, except for a slightly better cardiac index and indexed systemic vascular resistances at the end of CPB and at intensive therapy unit (ITU) admission (p < 0.05). Transaminases, bilirubin, amylase, proved lower in group B (p < 0.05 from ITU admission to 48 hours). Creatinine clearance, serum creatinine, and lactate were better in group B (p < 0.05), and acute renal insufficiency was accordingly lower (p = 0.02). Respiratory response demonstrated better Pao2/Fio2 and respiratory compliance from aortic declamping to 48 hours, with better scoring of chest radiograph (p < 0.05 from ITU admission to 48 hours), lower noninvasive positive-pressure ventilation (p = 0.002) and intubation time (p = 0.031) in group B. Lower chest drainage (p < 0.05 at first and second day), transfusions (p < 0.05), activated partial thromboplastin time, international normalized ratio, white blood cells, and D-dimer (p < 0.05 from ITU admission to 48 hours), together with higher platelets, fibrinogen, and antithrombin III (p < 0.05 from ITU admission to 48 hours) were demonstrated in the pulsated group.
Conclusions: IABP-induced pulsatile flow significantly improves whole body perfusion in the elderly undergoing CPB.