Effect of pentoxifylline on preventing acute kidney injury after cardiac surgery by measuring urinary neutrophil gelatinase - associated lipocalin.

BACKGROUND: Based on Acute Kidney Injury Network (AKIN) criteria, we considered acute kidney injury (AKI) as an absolute increase in the serum creatinine (sCr) level of more than or equal to 0.3 mg/dl or 50%. The introduction of Urinary neutrophil gelatinase-associated lipocalin (UNGAL) has conferred earlier diagnosis of AKI. Pentoxifylline (PTX), a non-specific phosphodiesterase inhibitor, can suppress the production of some factors of inflammatory response and presumably prevent AKI. We examined the PTX on the development of AKI in cardiac surgery patients by measuring the levels of UNGAL. MATERIALS AND METHODS: We performed a double blind randomized clinical trial, enrolling 28 consecutive patients undergoing elective coronary artery bypass graft (CABG) surgery. Patients were divided into two groups, one to receive PTX 5 mg/kg intravenous bolus injection, followed by 1.5 mg/kg/h continuous intravenous infusion until 3 hours after cessation of CPB and the other group received placebo. UNGAL was measured before, 3 and 24 hours after surgery. In addition serum creatinine was measured before and 24, 48, 72 and 96 hours after surgery and C-reactive protein (CRP) only 24 hours postoperatively. RESULTS: Both groups did not differ in demographic and baseline characteristics. 12 patients developed AKI 48 hours after surgery; 5 of them were in the intervention group and 7 in the control group (p= 0.445). There was an increase of UNGAL in both groups postoperatively, although not significant. Mean sCr was significantly increased in the control group at 24 and 48 hours after surgery (24-h mean: 0.79 ± 0.18 mg/dl vs. 1.03 ± 0.43 mg/dl, P value = 0.02; 48-h mean: 1.17 ± 0.24 mg/dl vs. 0.98 ± 0.20 mg/dl, P value = 0.03, respectively). PTX had a positive effect in preventing AKI reflecting in changes in sCr, and the increase of UNGAL was consistent with the emergence of AKI (Pearson's correlation = 0.30). CONCLUSION: Our study demonstrates a weak correlation between UNGAL and sCr after cardiac surgery. The rise of UNGAL in these patients may be reduced by administration of PTX although we did not show significance. PTX could reduce the occurrence of AKI as determined by attenuation of sCr rise without causing hemodynamic instability or increased bleeding. Overall, we suggest future studies with larger sample sizes to elucidate this effect and determine the different aspects of administrating PTX. TRIAL REGISTRATION: ISRCTN: IRCT138807302622N1.

Antibody response to influenza immunization in coronary artery disease patients: a controlled trial.

Safety of and humoral immune response to the anti-influenza vaccine in coronary artery disease (CAD) patients were evaluated. The trivalent vaccine was administered to 137 eligible CAD patients and 67 age- and sex-matched healthy individuals. Antibody (Ab) titers were measured before and 1 month after vaccination. CAD and HC groups were not significantly different in serologic response and magnitude of change in antibody titers against each of the vaccine antigens. In multivariate analyses, regular exercise and using multivitamin supplements were independently associated with better antibody response among CAD patients. There were no major cardiac or general adverse effects. Influenza vaccine was found safe in CAD patients and antibody responses were similar to HCs.

Relationship between serum magnesium level and arrythmias following post-coronary artery bypass grafting.

INTRODUCTION: Atrial and ventricular arrhythmias are among the most common complications after coronary artery bypass graft (CABG) surgery. It is known that cardiopulmonary bypass reduces serum magnesium level. In this study, we evaluated the relationship between total blood magnesium level (TMG) and the incidence of perioperative arrhythmias. METHODS: TMG was measured in patients who were scheduled for CABG on three occasions: just before anesthesia, on intensive care unit (ICU) arrival and on the first morning after operation. Patients were evaluated for primary cardiac rhythm, serum creatinine, urine output in operating room and diuretic therapy. Supplemental magnesium (SMG) was also recorded in operating room and ICU. Patients were then evaluated for the rate and kind of arrhythmia occurring during the next 3 days. RESULTS: Mean TMG level in 170 cases was 2.2 (0.5), 2.6 (0.6) and 2.4 (0.6) mg/dl on three occasions respectively. 53 patients developed post-operative arrhythmia (31%) [Atrial Fibrillation (AF) (7.1%), Non-AF Supraventricular arrhythmia (14.7%) and Ventricular arrhythmia (16.5%)]. Although there was a significant difference between TMG on three occasions (P <0.001), all values were within normal range. Although TMG was higher in arrhythmic patients compared to non- arrhythmics (2.26 vs. 2.14), both values were in normal range and there was no significant difference between two groups. DISCUSSION: This study shows that routine magnesium administration has no significant effect on serum magnesium level. We conclude that though routine regimen of magnesium administration has no effect on incidence of perioperative arrhythmia, it is probably necessary for maintaining normal magnesium level.

Magnesium infusion and postoperative atrial fibrillation: a randomized clinical trial.

BACKGROUND: Postoperative arrhythmias are among the most common complications of cardiac surgery. Total serum magnesium concentration will change after coronary bypass surgery but compensatory prophylactic administration of magnesium has remained a controversial issue. We studied whether prophylactic administration of magnesium could prevent post-coronary artery bypass grafting (CABG) arrhythmias and evaluated the effects of diabetes mellitus on prophylactic magnesium administration. METHODS: In a clinical trial, 345 consecutive CABG candidates were randomly assigned to study (n = 166, 48.1%) and control groups. Patients in study group received supplemental magnesium infusion as following: 2 g [corrected] after induction of anesthesia until cardio-pulmonary bypass and then 8 g upon arrival in Intensive Care Unit (ICU) until 24 hr. Total serum magnesium concentration was measured at four designated time points: onset of induction, and 0, 24 and 48 hr after ICU admission. Cardiac arrhythmias were sought with a 12-lead electrocardiogram (ECG) from the end of surgery up till discharge. RESULTS: Atrial Fibrillation (Af) occurred in 34 patients (9.9%). Total serum magnesium concentration was significantly higher in patients who received supplemental magnesium (P < 0.001) and significantly lower in Af patients (P= 0.02). Among non-diabetics, Af incidence was significantly lower in study group compared with control group. CONCLUSIONS: The occurrence of atrial fibrillation correlates with serum magnesium level. Diabetes mellitus probably hampers prophylactic effect of supplemental magnesium in preventing the occurrence of Af.