Ozan Onur Balkanay

The dose-related effects of dexmedetomidine on renal functions and serum neutrophil gelatinase-associated lipocalin values after coronary artery bypass grafting: a randomized, triple-blind, placebo-controlled study.

OBJECTIVES Acute kidney failure after coronary artery bypass grafting (CABG) is a serious complication that increases morbidity and mortality rates. Early detection and prevention of this complication are very important. A novel biomarker named neutrophil gelatinase-associated lipocalin (NGAL) can play an important role in early diagnosis of acute kidney injury. Recent studies on the favourable effects of Dexmedetomidine on cardiac surgery have been published. The aim of this study is to investigate whether there is a dose-dependent positive effect of Dexmedetomidine on neutrophil gelatinase-associated lipocalin levels and renal functions when used after CABG. METHODS Our randomized, triple-blinded, placebo-controlled study was conducted among 295 patients scheduled for CABG surgery between August 2009 and March 2011 in a tertiary cardiac and vascular surgery clinic. A total of 90 consecutive patients who met inclusion criteria were randomized and divided into three groups. The first group received a placebo. The second and the third groups received 4 and 8 µg/cc concentration of the Dexmedetomidine infusion, respectively. Infusion rates were regulated to obtain sedation with a Ramsey sedation score of 2 or 3. Patients were regrouped according to the total Dexmedetomidine dose. Statistical analyses of variables including serum neutrophil gelatinase-associated lipocalin values and conventional renal function tests were made for all six possibilities before the blind was broken. RESULTS Results of conventional renal function tests were not significantly different. However, neutrophil gelatinase-associated lipocalin levels for the first postoperative day for placebo, low-dose and high-dose Dexmedetomidine groups were 176.8 ± 145.9, 97.7 ± 63.4 and 67.3 ± 10.9 ng/ml, respectively. These values were significantly different among the groups (P <0.001). CONCLUSIONS In our study, we found that Dexmedetomidine infusion for sedation after CABG under cardiopulmonary bypass can be useful in the prevention of kidney injury. Conventional renal function tests, including blood urea nitrogen, serum creatinine, urine output and creatinine clearance rate measurements typically may not detect the development of acute kidney dysfunction in the first 48-h postoperative period. Differences were detected in renal function in the early postoperative period and the development of acute kidney injury, as determined by measurements of blood NGAL levels, was significant and dose-dependent.

Aorta-right atrial tunnel in an adult

Aorta-right atrial tunnel was diagnosed in a non-symptomatic 31-year old female patient. The Q p /Q s ratio was 2.5. Computed tomography and intraoperative views showed a posterior vascular tunnel with left aortic sinus and right atrium openings (Figs 1 and 2). The tunnel had no myocardial branches. We successfully closed both the openings. Figure 1: (A) A reconstructed computed tomographic view of the aorta-right atrial tunnel, which passed along the posterior aspect of the aorta (arrows indicate the tunnel). (B) The aortic origin of the aorta-right atrial tunnel (arrow indicates the origin of the tunnel where a surgical aspirator is situated)

Thoracoabdominal aortic mural and floating thrombus extending into superior mesenteric artery

Thrombus in the thoracic aorta not related to aneurysm or atherosclerosis is a rare clinical entity with a limited number of cases reported. Floating thrombus is defined as non-adherent part of the thrombus floating within the aortic lumen. Herein, we present a 48-year-old woman who presented with progressive midline dull, aching abdominal pain of 2-day duration. Thoracoabdominal computed tomography revealed a free floating thrombus extending from the aortic arch into the superior mesenteric artery. Transesophageal echocardiography confirmed the findings of a thrombus extending through the aortic arch. Floating thrombus within the aortic lumen in a morphologically normal descending thoracic and abdominal aorta is a rare entity.

The Reliability of the Use of Serum Neutrophil Gelatinase–Associated Lipocalin Levels in the Assessment of Renal Functions after Coronary Artery Bypass Grafting

Objective Evaluation of perioperative renal function is very important for early diagnosis and treatment of acute kidney injury after coronary artery bypass grafting. Serum creatinine levels, creatinine clearance, and estimated glomerular filtration rates used in determination of postoperative kidney injury can lead to late detection. Therefore, it is necessary to make a diagnosis earlier in clinical practice and to search for a reliable method. The reliability of the use of serum neutrophil gelatinase–associated lipocalin levels in close follow-up of renal function was evaluated in patients with coronary artery bypass grafting under cardiopulmonary bypass in our study. Patients and Methods A total of 40 patients who underwent coronary artery bypass grafting under cardiopulmonary bypass between September 2009 and February 2010 were included in the study. The reliability of the postoperative 1st day plasma neutrophil gelatinase–associated lipocalin (Triage® NGAL Device; Biosite Inc.) measurements was evaluated in kidney injury developed in the first 5 days after operation that was detected using the Risk-Injury-Failure-Loss-End stage criteria. Results Ten (25%) women and 30 (75%) male patients were included in the study. The average age is 59 ± 8.6 years. Kidney injury according to Risk-Injury-Failure-Loss-End stage criteria developed in 8 patients (20%). For 150 ng/mL cutoff value of postoperative plasma neutrophil gelatinase–associated lipocalin levels, the area under the receiver-operating characteristic curve was 0.965. Neutrophil gelatinase–associated lipocalins sensitivity, specificity, and negative and positive predictive values were 100%, 93.8%, 100%, and 80%, respectively. Conclusion It has been determined that plasma neutrophil gelatinase–associated lipocalin levels can be reliably used for early diagnosis of kidney dysfunction in patients undergoing coronary artery bypass grafting.

The Surgical Treatment of Primary Cardiac B-Cell Lymphoma of Clinically Unstable Patient

The incidence rate of primary cardiac tumors is 13.8 per 1 million inhabitants per year, and 2.4% of them consist of primary cardiac lymphoma. Primary cardiac lymphoma is a fatal malignancy. Echocardiography and whole-body computed tomography are useful tools for diagnosis. Although chemotherapy has been previously described as the standard treatment for primary cardiac lymphoma, surgical treatment can be used for clinically unstable patients. Herein we report the first surgically treated case of a 57-year-old man with biatrial involvement of primary cardiac B-cell lymphoma.

Relaxant effect of the prostacyclin analogue iloprost on isolated human radial artery: An approach for the reversal of graft spasm

Radial artery graft spasm in the perioperative or postoperative period of coronary bypass surgery necessitates urgent treatment due to risk of graft failure and mortality. Herein, we evaluated the effect of iloprost, a prostacyclin (PGI2) analogue, against the contractions produced by noradrenaline and potassium chloride on isolated human radial artery. Following the determination of endothelial and vascular relaxing capacities of the arteries, iloprost (10-9M-10-6M) was cumulatively applied on rings precontracted submaximally with the spasmogens. In some rings, the response to iloprost was assessed following pretreatment with nitric oxide (NO) synthase inhibitor, l-NAME (3×10-4M,30min). Iloprost produced complete relaxations on radial artery rings precontracted with noradrenaline whereas, only moderate relaxations against the contractions induced by potassium chloride. Notably, the relaxation to iloprost was remarkably blunted in radial arteries with impaired endothelial function. Moreover, the relaxation to iloprost was unchanged in rings pretreated with l-NAME. Our results demonstrated that iloprost could be a potent relaxant agent in reversing radial artery spasm, particularly initiated by noradrenaline, possibly acting via an endothelium-mediated mechanism unrelated to NO.

Approach to peripheral arterial disease in the elderly

The prevalence of peripheral arterial disease, which usually develops on the basis of atherosclerosis and develops as a result of chronic arterial occlusive pathology, increases with age. Peripheral artery disease in the elderly patient population may be asymptomatic due to restrictive conditions associated with immobilization. Concurrent cerebrovascular disease and coronary artery disease risk and mortality rates are higher in elderly patients with peripheral artery disease. The life expectancy in patients with peripheral arterial disease is worse than in prostate cancer patients. Leading risk factors include advanced age, smoking, diabetes mellitus, hypertension, hyperlipidemia, hyperhomocysteinemia and hypothyroidism. The most important physical examination component is the palpation of the entire peripheral pulses. The cases in which the ankle-brachial systolic pressure index measurement for clinical diagnosis is below 0.9 are defined as peripheral arterial disease. It is aimed to completely correct or improve the existing clinical symptoms and to increase the survival rates of the patients. The existing risk factors are modified as the first step of the treatment. Smoking cessation, treatment of hypertension primarily with angiotensin-converting enzyme inhibitors, lowering of hemoglobin A1c levels below 7%, anti-hyperlipidemic treatment primarily with statin, antiaggregant therapy primarily with clopidogrel, cilostazol therapy, good foot care, controlled exercise program, if necessary, interventional or operational revascularization, amputation in the presence of irreversible effects are the main treatment components. Indications for major revascularization include the presence of resting pain in the limb and / or open and long-lasting unhealed wound in the extremity and / or severe complaints of intermittant claudication that will result in limitation in daily activities. It should not be forgotten that, all the clinical decisions to be taken in the treatment of elderly patients with peripheral arterial disease are determined by the patients physical condition, current clinical condition and the expectation level of the patient.