Urinary neutrophil gelatinase-associated lipocalin time course during cardiac surgery.

Background: NGAL is one of the most promising AKI biomarkers in cardiac surgery. However, the best timing to dose it and the reference values are still matter of discussion. Aim of the Study: We performed a uNGAL perioperative time course, to better understand its perioperative kinetics and its role in AKI diagnosis. Setting of the Study: San Raffaele University Hospital, cardiac surgery department. Material and Methods: We enrolled in this prospective observational study 19 patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). Based on preoperative characteristics, they were divided in low-risk and high-risk patients. uNGAL measurements were collected at pre-defined times before, during, and up to 24 hours after surgery. Statistical Analysis: Data were analysed by use of SAS 1999-2001 program or IBM SPSS Statistics. Results: In low-risk patients, uNGAL had the highest value immediately after general anesthesia induction (basal dosage: uNGAL: 12.20ng×ml-1, IQR 14.00). It later decreased significantly (3.40 ng×ml-1, IQR 4.80; P = 0.006) during CPB, and finally return to its original value 24 hours after surgery. In high-risk patients, uNGAL increased immediately after surgery; it had the highest value on ICU arrival (38,20 ng×ml-1; IQR 133,10) and remained high for several hours. A difference in uNGAL levels between the two groups was already observed at the end of surgery, but it became statistically significant on ICU arrival (P = 0.002). Conclusion: This study helps to better understand the different kinetics of this new biomarker in low-risk and high-risk cardiac patients.

A survey on the use of intra-aortic balloon pump in cardiac surgery.

Intra-aortic balloon pump (IABP) is an established tool in the management of cardiac dysfunction in cardiac surgery. The best timing for IABP weaning is unknown and varies greatly among cardiac centers. The authors investigated the differences in IABP management among 66 cardiac surgery centers performing 40,675 cardiac surgery procedures in the 12-month study period. The centers were contacted through email, telephone, or in person interview. IABP management was very heterogeneous in this survey: In 43% centers it was routinely removed on the first postoperative day, and in 34% on the second postoperative day. In 50% centers, it was routinely removed after extubation of the patients whereas in 15% centers it was removed while the patients were sedated and mechanically ventilated. In 66% centers, patients were routinely receiving pharmacological inotropic support at the time of removal of IABP. The practice of decreasing IABP support was also heterogeneous: 57% centers weaned by reducing the ratio of beat assistance whereas 34% centers weaned by reducing balloon volume. We conclude that the management of IABP is heterogeneous and there is a need for large prospective studies on the management of IABP in cardiac surgery.