Mert Akan

Risk Factors for Early Bacterial Infections in Liver Transplantation

OBJECTIVE Our aim was to determine perioperative risk factors for early bacterial infection after liver transplantation. METHODS Retrospectively examining medical records using Centers for Disease Control and Prevention (CDC) definitions to identify nosocomial infections, we analyzed data on 367 adult patients. RESULTS The incidence of infection was 37.3% (n = 137): namely, surgical site (n = 74; 20.2%) [corrected], blood stream (n = 64; 17.4%), pulmonary (n = 49; 13.4%), urinary system (n = 26; 7.1%). Significant risk factors within the first 30 days were as follows: deceased donor, Model for End-Stage Liver Disease (MELD) >20, albumin level <2.8 g/dL, intraoperative erythrocyte transfusion >6 U, intraoperative fresh frozen plasma >12 U, bilioenteric anastomosis, postoperative intensive care unit stay >6 days, and postoperative length of stay >21 days. Significant risk factors detected within the first 90 days were as follows: MELD >20, preoperative length of stay >7 days, reoperation, postoperative length of intensive care unit stay >6 days, and postoperative length of stay >21 days. Variability was observed in risk factors according to localization of infection. As a result, except for MELD, type of donor, and biliary anastomosis, the others are preventable factors for early bacterial infection. In addition, the same risk factors showed variability according to the site of infection.

Comparison of effects of preoperatively administered lornoxicam and tenoxicam on morphine consumption after laparoscopic cholecystectomy.

Background and objective: The efficacy, tolerability and the morphine‐sparing effects of lornoxicam were compared with those of tenoxicam when used preoperatively in patients undergoing laparoscopic cholecystectomy. Methods: In this prospective, double‐blind study, 60 ASA I–II patients undergoing laparoscopic cholecystectomy were randomized equally to receive intravenous tenoxicam 40 mg (Group T) or lornoxicam 16 mg (Group L), preemptively. Three patients withdrew from the study, so 57 patients were included in the analysis. In the postoperative period, the first morphine demand times, pain scores, side‐effects and cumulative morphine consumptions were evaluated during the first 24 h. Results: The patient characteristics data and the duration of surgery were similar between two groups, except for body weights (P = 0.002). The first morphine demand time was significantly longer in Group L (P = 0.037), but the pain levels did not differ. The mean pain scores were higher in Group T in the 15 min (P = 0.036), 1 h (P = 0.020), 2 h (P = 0.001) and 4 h (P = 0.0042) after extubation. A statistically significant difference between two groups was found in calculated cumulative morphine consumptions per kilogram in the 15 min (P = 0.037), 30 min (P = 0.016), and 1 h (P = 0.004) and 2 h (P = 0.013) between two groups. There was no difference in the severity of nausea but 13 patients in Group T and five patients in Group L had vomiting (P = 0.018). Patient satisfaction was similar in the two groups. Conclusions: Preoperatively administered lornoxicam 16 mg significantly prolonged the first morphine demand time, reduced postoperative morphine consumption during the first 4 h and caused significantly fewer adverse effects when compared with tenoxicam after laparoscopic cholecystectomy.

A possible perianesthetic serotonin syndrome related to intrathecal fentanyl

Serotonin syndrome occurs with selective serotonin reuptake inhibitors, opioids, and other serotonergic agents. We describe a possible serotonin syndrome related to intrathecal fentanyl in a patient taking multiple drugs and substances such as ergot alkaloids, marijuana, methylenedioxy-N-methylamphetamine, and ephedrine.

Acute Renal Injury Evaluation after Liver Transplantation: With RIFLE Criteria

BACKGROUND The aim of this study was to identify acute renal injury (ARI) through the use of RIFLE (risk, injury, failure, loss, end-stage kidney disease) criteria and to investigate perioperative risk factors for ARI in liver transplantation (LT). METHODS We reviewed medical records of adult LT patients retrospectively. Postoperative ARI was staged with RIFLE criteria by the 1st and 7th days of the surgery. RESULTS We analyzed 440 adult LT patients, categorized as risk (R), injury (I), or failure (F) according to the RIFLE criteria. In this study, in the first postoperative day, incidence of ARI was 7.95%; all of them were R-class, and, on the 7th day, the incidence of ARI was 7.27%, as R-class 6.59% and I-class 0.68%. Significant risk factors were detected within the first postoperative day including pre-operative hemoglobin levels <9 g/dL (P = .019), intra-operative transfusion of red blood cells (RBCs) (P = .049) and fresh-frozen plasma (FFP) (P = .049), blood loss (P = .011), and post-reperfusion syndrome (P = .023). Multivariate analysis revealed risk factors for ARI as RBCs (odds ratio [OR], 1.049; P = .247) and FFP (OR, 1.017; P = .627) transfusion and blood loss (OR, 1.000; P = .021) (blood loss OR: 0.9996952300184; 95% confidence interval: 0.9994356774026 to 0.999548500399). The only significant risk factor for the 7th postoperative day was the Model for End-Stage Liver Disease (MELD) score (>20) (P = .002). CONCLUSIONS This study showed that RBC and FFP transfusion, perioperative blood loss, and MELD score >20 are risk factors for LT-related ARI. Also normalization of hemoglobin levels with non-blood products in patients with preoperative low hemoglobin levels can diminish the need for RBC and that can prevent ARI.

Comparison of the effects of dexmedetomidine administered at two different times on renal ischemia/reperfusion injury in rats

BACKGROUND AND OBJECTIVES We investigated the effect of dexmedetomidine on ischemic renal failure in rats. METHODS In the present study, 26 male adult Wistar albino rats weighting 230-300 g were randomly separated into four groups: sham-operated (n=5), ischemia reperfusion (IR) (IR group, n=7), IR/reperfusion treatment with dexmedetomidine (Dex. R group, n=7) and IR/pre-ischemic treatment with dexmedetomidine (Dex. I group, n=7). In the first group, sham operation was achieved and renal clamps were not applied. For the IR group, renal ischemia was induced by occlusion of the bilateral renal arteries and veins for 60 min followed by reperfusion for 24h. For the Dex. R and Dex. I groups, the same surgical procedure as in the IR group was performed, and dexmedetomidine (100 mcg/kg intraperitoneal) was administrated at the 5th min after reperfusion and before ischemia. At the end of reperfusion, blood samples were drawn, the rats were sacrificed, and the left kidney was processed for histopathology. RESULTS The blood urea nitrogen (BUN) levels in groups Dex. R and Dex. I were significantly lower than in the IR group (p=0.015, p=0.043), although urine flow was significantly higher in group Dex. R (p=0.003). The renal histopathological score in the IR group was significantly higher than in the other groups. There was no significant difference between the Dex. R and Dex. I groups. CONCLUSIONS The results were shown that administration of dexmedetomidine reduced the renal IR injury histomorphologically. Administration of dexmedetomidine in the reperfusion period was considered as more effective due to increase in urinary output and decrease in BUN levels.

Effects of blood products on nosocomial infections in liver transplant recipients.

OBJECTIVES Infection is the most severe complication after an organ transplant. Blood cell transfusion is an independent risk factor for adverse events, including infection in the recipient. This study sought to evaluate the effect of blood product transfusions on nosocomial infections in liver transplant patients. MATERIALS AND METHODS Patients who underwent a liver transplant at our hospital between 2003 and 2010 were recruited for this study. Exclusion criteria were incomplete records, patients who were hospitalized for more than 48 hours during the 4 weeks before transplant, and pediatric transplants. Incidence of nosocomial infections, which were defined as infections occurring within 30 days after transplant was the primary endpoint. RESULTS The incidence of nosocomial infections was 28.7%. The number of transfusions of packed red blood cells and fresh frozen plasma was significantly higher in patients with nosocomial infection compared with patients without nosocomial infection (P = .018 and P = .039). Blood products dose-dependently contributed to nosocomial infections. Transfusions of ≥ 7.5 units of red blood cells (odds ratio: 2.8) or ≥ 12.5 units of fresh frozen plasma (odds ratio: 3.27) were associated with nosocomial infections (P = .042 and P = .015). The infection-related mortality rate was 10.3%. CONCLUSIONS Blood product transfusions are associated with an increased rate of nosocomial infections, which contributes to higher morbidity and mortality.

Efeitos de dexmedetomidina em conjunto com o pré-condicionamento isquêmico remoto em lesão de isquemia-reperfusão renal em ratos

BACKGROUND AND OBJECTIVES The aim of this study was to evaluate the effects of remote ischemic preconditioning by brief ischemia of unilateral hind limb when combined with dexmedetomidine on renal ischemia-reperfusion injury by histopathology and active caspase-3 immunoreactivity in rats. METHODS 28 Wistar albino male rats were divided into 4 groups. Group I (Sham, n=7): Laparotomy and renal pedicle dissection were performed at 65th minute of anesthesia and the rats were observed under anesthesia for 130min. Group II (ischemia-reperfusion, n=7): At 65th minute of anesthesia bilateral renal pedicles were clamped. After 60min ischemia 24h of reperfusion was performed. Group III (ischemia-reperfusion+dexmedetomidine, n=7): At the fifth minute of reperfusion (100μg/kg intra-peritoneal) dexmedetomidine was administered with ischemia-reperfusion group. Reperfusion lasted 24h. Group IV (ischemia-reperfusion+remote ischemic preconditioning+dexmedetomidine, n=7): After laparotomy, three cycles of ischemic preconditioning (10min ischemia and 10min reperfusion) were applied to the left hind limb and after 5min with group III. RESULTS Histopathological injury scores and active caspase-3 immunoreactivity were significantly lower in the Sham group compared to the other groups. Histopathological injury scores in groups III and IV were significantly lower than group II (p=0.03 and p=0.05). Active caspase-3 immunoreactivity was significantly lower in the group IV than group II (p=0.01) and there was no significant difference between group II and group III (p=0.06). CONCLUSIONS Pharmacologic conditioning with dexmedetomidine and remote ischemic preconditioning when combined with dexmedetomidine significantly decreases renal ischemia-reperfusion injury histomorphologically. Combined use of two methods prevents apoptosis via active caspase-3.

The Effects of Remote Ischemic Preconditioning and N-Acetylcysteine with Remote Ischemic Preconditioning in Rat Hepatic Ischemia Reperfusion Injury Model

Background. Remote ischemic preconditioning (RIP) and pharmacological preconditioning are the effective methods that can be used to prevent ischemia reperfusion (IR) injury. The aim of this study was to evaluate the effects of RIP and N-Acetylcysteine (NAC) with RIP in the rat hepatic IR injury model. Materials and Methods. 28 rats were divided into 4 groups. Group I (sham): only laparotomy was performed. Group II (IR): following 30 minutes of hepatic pedicle occlusion, 4 hours of reperfusion was performed. Group III (RIP + IR): following 3 cycles of RIP, hepatic IR was performed. Group IV (RIP + NAC + IR): following RIP and intraperitoneal administration of NAC (150 mg/kg), hepatic IR was performed. All the rats were sacrificed after blood samples were taken for the measurements of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and liver was processed for conventional histopathology. Results. The hepatic histopathological injury scores of RIP + IR and RIP + NAC + IR groups were significantly lower than IR group (P = 0.006, P = 0.003, resp.). There were no significant differences in AST and ALT values between the IR, RIP + IR, and RIP + NAC + IR groups. Conclusions. In the present study, it was demonstrated histopathologically that RIP and RIP + NAC decreased hepatic IR injury significantly.

Comparison of the RIFLE, AKIN, and KDIGO Diagnostic Classifications for Acute Renal Injury in Patients Undergoing Liver Transplantation

BACKGROUND The aim of this study was to determine the incidence and peri-operative risk factors for acute renal injury (ARI) and their relationship with mortality rate through the use of 3 different ARI diagnostic classifications in patients after liver transplantation (LT). METHODS We retrospectively investigated the medical records of adult LT recipients. Post-operative ARI was determined with the Risk, Injury, Failure, Loss, and End-Stage Renal Failure (RIFLE), Acute Kidney Injury Network (AKIN), and Kidney Disease: Improving Global Outcomes (KDIGO) classifications. RESULTS We analyzed 440 adult patients. The post-operative incidence of ARI was 8.0% by the RIFLE classification, 14.31% by the AKIN classification, and 14.54% by the KDIGO classification. Significant risk factors for ARI were pre-operative albumin (odds ratio [OR], 0.776; 95% confidence interval [CI], 0.473-1.273 for AKIN; and OR, 0.724; 95% CI, 0.444-1.182 for KDIGO) and hemoglobin levels (OR, 2.830; 95% CI, 1.157-6.9261 by RIFLE), intra-operative red blood cell transfusion (OR, 1.072; 95% CI, 1.004-1.143 by AKIN; and OR, 1.077; 95% CI, 1.011-1.147 by KDIGO), and blood loss (OR, 1.00; 95% CI, 0.999-1.000 by RIFLE). The early mortality rate was 7.9% in our series. CONCLUSIONS The RIFLE, AKIN, and KDIGO ARI classifications classify the severity of renal dysfunction in patients who have undergone LT. Direct associations were found between higher mortality rates and severity of renal disease.

Renal Ischemia/Reperfusion Injury in Diabetic Rats: The Role of Local Ischemic Preconditioning

Background. The aim of this study was to evaluate the effects of local ischemic preconditioning using biochemical markers and histopathologically in the diabetic rat renal IR injury model. Methods. DM was induced using streptozotocin. Rats were divided into four groups: Group I, nondiabetic sham group (n = 7), Group II, diabetic sham group (n = 6), Group III, diabetic IR group (diabetic IR group, n = 6), and Group IV, diabetic IR + local ischemic preconditioning group (diabetic IR + LIPC group, n = 6). Ischemic renal injury was induced by clamping the bilateral renal artery for 45 min. 4 h following ischemia, clearance protocols were applied to assess biochemical markers and histopathologically in rat kidneys. Results. The histomorphologic total cell injury scores of the nondiabetic sham group were significantly lower than diabetic sham, diabetic IR, and diabetic IR + LIPC groups. Diabetic IR group scores were not significantly different than the diabetic sham group. But diabetic IR + LIPC group scores were significantly higher than the diabetic sham and diabetic IR groups. Conclusion. Local ischemic preconditioning does not reduce the risk of renal injury induced by ischemia/reperfusion in diabetic rat model.