*Perfusionist
**Perfusionist-Instructor
***Chief Perfusionist,
****Associate Professor
*****MCh. Registrar, Professor and Head
Department of Cardiothoracic Surgery, Christian Medical College, Vellore
Presented at the 12th Annual Conference of the Indian Society of Extra-Corporeal Technology February 2012, Kolkata, India
Various factors are indicated as causes of cardiac surgery associated acute kidney injury (CSA-AKI). Controversy continues as to the significance of maintenance of optimal mean arterial pressure (MAP) during cardiopulmonary bypass (CPB) in preserving renal function. We undertook a prospective observational study to assess the role of low (MAP) in causing CSA-AKI.
To evaluate the association between MAP during CPB and acute renal injury in adult patients undergoing for open heart surgery using CPB in the Christian medical College Hospital, Vellore.
One hundred and twelve consecutive adult patients who underwent cardiac surgery under CPB were included in the study. Patients with pre-operative serum creatinine value more than 1.4 mg% were excluded. The MAP during surgery was tabulated and its correlation to post-operative renal function was analyzed.
The mean age was 49.12 years. Coronary artery bypass pass grafting (CABG) was performed in 61.61% of patients and valve replacement in 38.4%. The mean intra-operative MAP was 48.11 mmHg. Twenty one patients (18.75%) were found to have risk of CSA-AKI as per RIFLE criteria and of these 4 patients developed CSA-AKI. There was an association between low MAP with CSA-AKI, which is significant (p-value=0.035) at 5% level. Besides MAP, eight additional variables were also studied, three of these factors (age, Aortic cross clamp time, and CPB time) also showed significance in causing CSA-AKI.
Low mean arterial blood pressure during CPB is one of the risk factors for acute kidney injury even in patients with normal serum creatinine level.
Acute kidney injury, blood pressure, cardiopulmonary bypass, mean arterial pressure
