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Surgery Today | 2007

Iatrogenic Major Venous Injuries Incurred During Cancer Surgery

Gursel Levent Oktar

PurposeIatrogenic operative injury to the major veins is associated with significant morbidity and mortality. This study was conducted to review the pattern, management, and outcome of iatrogenic major venous injuries incurred during cancer surgery.MethodsWe reviewed 24 patients with collective 30 venous injuries, evaluating clinical characteristics; operative and postoperative data, including location and type of venous injury, operative repair, blood loss, and transfusion requirements; and outcome.ResultsThirty venous and 12 associated arterial injuries were identified. The two most common sites of venous trauma were the iliac and femoral veins with 10 (33.3%) and 9 (30.0%) injuries, respectively. Twenty-three (76.7%) of the venous injuries were repaired primarily or with end-to-end anastomosis, while the remaining injuries required interposition grafts, patch venoplasty, or venous ligation. Postoperative revision procedures were performed in 3 (12.5%) patients. Perioperative mortality was 16.7% and major complications developed in 11 (45.8%) patients.ConclusionsSerious complications can be minimized by immediate recognition and prompt repair of iatrogenic vascular injuries. Close collaboration with a vascular surgeon during resection of tumors in proximity to the vascular structures may be helpful in preventing iatrogenic vascular injuries. In hospitals where tumor resection procedures are frequently performed, a vascular surgeon must be readily available.


Wound Repair and Regeneration | 2015

Effects of VEGF and MSCs on vascular regeneration in a trauma model in rats.

Mehmet Niyaz; Özer Aylin Gürpinar; Gursel Levent Oktar; Serdar Gunaydin; Mehmet Ali Onur; Kadir Kaan Özsin; Ali Yener

In the human body, vascular injuries that are caused by trauma, vessel lumen stenosis, and occlusions are often irreversible and can lead to sequelae formation as the vessels cannot reproduce fast enough. To solve this problem, the blood flow must be returned to the region as fast as possible. The adipose tissue contains progenitor cells with angiogenic potential and can be used to resolve the issue.


Journal of Surgical Research | 2013

Effects of adrenomedullin and vascular endothelial growth factor on ischemia/reperfusion injury in skeletal muscle in rats

Mehmet Kirişçi; Gursel Levent Oktar; Candan Ozogul; Eser Öz Oyar; Seda Nur Akyol; Canan Demirtas; Mustafa Arslan

BACKGROUND In this study we investigated the effects of adrenomedullin (AM) and vascular endothelial growth factor (VEGF) on skeletal muscle ischemia/reperfusion (I/R) injury in a rat model. MATERIALS AND METHODS Thirty-six Wistar rats were randomized into six groups (n = 6). Laparotomy was performed in all groups under general anesthesia. Nothing else was done in Group S (Sham). The Group I/R underwent I/R performed by clamping and declamping of the infrarenal abdominal aorta for 120 min, respectively. Group VEGF and Group AM received intravenous infusion of VEGF (0.8 μg/kg) or AM (12 μg/kg) respectively, without I/R. Group I/R + VEGF and Group I/R + AM received intravenous infusion of VEGF (0.8 μg/kg) or AM (12 μg/kg) immediately after 2 h period of ischemia, respectively. At the end of reperfusion period, skeletal muscle samples of lower extremity were taken from all groups for biochemical and histopathologic examinations. RESULTS Tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), and hypoxia inducible factor 1 alpha (HIF 1α) were found to be significantly higher in Group I/R than the levels in Group S (P < 0.05). Tissue levels of MDA, SOD, NO, and HIF 1α were significantly lower in Group I/R + AM compared with the levels in Group I/R (P < 0.05). In Group I/R + VEGF, tissue levels of MDA and NO were significantly lower than the levels in Group I/R (P < 0.05). No statistically significant difference was found in the tissue levels of catalase among the groups. Histologic examination revealed a larger central muscular necrosis than the peripheral necrosis, red blood cells in the lumens of capillary vessels, and a stronger atrophy and elliptical or round shape in muscle fibers in Group I/R. Terminal deoxynucleotidyl transferase mediated dUPT nick end labeling (TUNEL)-positive cell count was significantly lower in groups I/R + AM and I/R + VEGF than Group I/R (P < 0.0001, P < 0.0001, respectively). CONCLUSIONS These results indicate that AM and VEGF have protective effects on I/R injury in skeletal muscle in a rat model.


Surgery Today | 2008

Traditional single patch versus the "Australian" technique for repair of complete atrioventricular canal defects.

Velit Halit; Gursel Levent Oktar; Veli Yildirim Imren; Erkan Iriz; Dilek Erer; Serdar Kula; Fatma Sedef Tunaoglu; Levent Gökgöz; Rana Olguntürk

PurposeA variety of operative techniques has been used to repair complete atrioventricular (AV) canal defects and satisfactory outcomes after single patch repairs have been reported. We report our comparative results of repairing complete AV canal defects between 1998 and 2006 using the traditional single patch and the “Australian” techniques.MethodsFourteen patients underwent traditional AV canal repair with the single patch technique (Group 1) and 11 patients underwent repair with the “Australian” technique (Group 2). All patients were examined with preoperative echocardiography and cardiac catheterization, and were followed up with echocardiography to evaluate AV valve and ventricular function.ResultsThere were two early postoperative deaths in Group 1 and one in Group 2. One patient from each group had moderate left AV valve regurgitation postoperatively, but none from either group had left ventricular outflow obstruction.ConclusionsThe “Australian” technique is a simpler method requiring shorter aortic cross-clamping and total bypass times with good clinical and functional results. The early postoperative results are as encouraging as those achieved by the traditional single patch technique; however, long-term follow-up results are required to establish the efficacy of this simplified technique.


Journal of Heart and Lung Transplantation | 2008

Right-to-left Shunt Through a Patent Foramen Ovale Left Open in the Management of Acute Right Heart Failure After Heart Transplantation

Mehmet Emin Ozdogan; Dilek Erer; Erkan Iriz; Gursel Levent Oktar; Serdar Kula; Mustafa Büyükateş

Severe pulmonary hypertension is a risk factor for mortality in heart transplantation due to elevated post-operative right heart failure. Various treatment modalities have been used in the management of pulmonary hypertension in the peri-operative period. We report a case of successful management of acute right heart failure after orthotopic heart transplantation by decompression of the right ventricle through the patent foramen ovale of the donor heart and inhalation of iloprost.


Drug Design Development and Therapy | 2016

Effects of alprostadil and iloprost on renal, lung, and skeletal muscle injury following hindlimb ischemia–reperfusion injury in rats

Dilek Erer; Abdullah Özer; Hüseyin Demirtaş; İpek Işık Gönül; Halil Kara; Hande Arpacı; Faruk Metin Çomu; Gursel Levent Oktar; Mustafa Arslan; Ayşegül Küçük

Objectives To evaluate the effects of alprostadil (prostaglandin [PGE1] analog) and iloprost (prostacyclin [PGI2] analog) on renal, lung, and skeletal muscle tissues after ischemia reperfusion (I/R) injury in an experimental rat model. Materials and methods Wistar albino rats underwent 2 hours of ischemia via infrarenal aorta clamping with subsequent 2 hours of reperfusion. Alprostadil and iloprost were given starting simultaneously with the reperfusion period. Effects of agents on renal, lung, and skeletal muscle (gastrocnemius) tissue specimens were examined. Results Renal medullary congestion, cytoplasmic swelling, and mean tubular dilatation scores were significantly lower in the alprostadil-treated group than those found in the I/R-only group (P<0.0001, P=0.015, and P<0.01, respectively). Polymorphonuclear leukocyte infiltration, pulmonary partial destruction, consolidation, alveolar edema, and hemorrhage scores were significantly lower in alprostadil- and iloprost-treated groups (P=0.017 and P=0.001; P<0.01 and P<0.0001). Polymorphonuclear leukocyte infiltration scores in skeletal muscle tissue were significantly lower in the iloprost-treated group than the scores found in the nontreated I/R group (P<0.0001). Conclusion Alprostadil and iloprost significantly reduce lung tissue I/R injury. Alprostadil has more prominent protective effects against renal I/R injury, while iloprost is superior in terms of protecting the skeletal muscle tissue against I/R injury.


Surgery Today | 2011

Saphenous vein wrapping for the treatment of a perigraft seroma: report of a case.

Yildirim Imren; Lawand Qaradaghi; Gursel Levent Oktar; Emrah Ereren; Naim Boran Tumer

A 61-year-old man who had undergone an iliofemoral bypass with an expanded polytetrafluoroethylene (PTFE) graft was readmitted to our hospital for the investigation and treatment of a possible complication of the surgery. A tender, pulsatile, bulging mass, about the size of an adult fist, was palpated around the left lower abdominal region. Diagnostic procedures showed a large low-density area around the PTFE graft and angiography revealed a patent graft with no anastomotic leakage. An operative inspection revealed the mass to be a large perigraft seroma. The PTFE graft was covered with a saphenous vein strip, a treatment that has not previously been mentioned in the literature. The success of this strategy was confirmed by clinical observations and diagnostic procedures including ultrasonography and computed tomography, with no sign of recurrence for 5 months.


Drug Design Development and Therapy | 2018

Assessment of the effects of levosimendan and thymoquinone on lung injury after myocardial ischemia reperfusion in rats

Şaban Cem Sezen; Ayşegül Küçük; Abdullah Özer; Yiğit Kılıç; Barış Mardin; Metin Alkan; Fatmanur Duruk Erkent; Mustafa Arslan; Yusuf Ünal; Gursel Levent Oktar; Murat Tosun

Aim The aim of this study was to investigate the effects of levosimendan and thymoquinone (TQ) on lung injury after myocardial ischemia/reperfusion (I/R). Materials and methods Twenty-four Wistar albino rats were included in the study. The animals were randomly assigned to 1 of 4 experimental groups. In Group C (control group), left anterior descending artery was not occluded or reperfused. Myocardial I/R was induced by ligation of the left anterior descending artery for 30 min, followed by 2 h of reperfusion in the I/R, I/R-levosimendan (24 µg/kg) (IRL) group, and I/R-thymoquinone (0.2 mL/kg) (IRTQ) group. Tissue samples taken from the lungs of rats were histochemically stained with H&E and immunohistochemically stained with p53, Bcl 2, Bax, and caspase 3 primer antibodies. Results Increased expression of p53 and Bax was observed (4+), especially in the I/R group. In IRTQ and IRL groups, expression was also observed at various locations (2+, 3+). H&E staining revealed that that the lungs were severely damaged and the walls of the alveoli were too thick, the number of areas examined was increased during the evaluation. Caspase 3 expression was observed to be at an (1+, 2+) intensity that was usually weak and diffuse in multiple areas. Bcl 2 was not found to be expressed in any of the tissues. H&E staining revealed that that the lungs were severely damaged in the I/R group, with the walls of the channels and alveoli thickened and edematous, and also an intense inflammatory cell migration was observed. Immunohistochemical staining was more prominent in inflammatory areas and structures around the terminal bronchioles. Conclusion The findings in our study have shown that administration of levosimendan and TQ during I/R increases expression of caspase 3, p53, and Bax in lung tissue and has a protective effect on lung as distant organ. We suggest that findings of this study be elucidated with further large-scale clinical studies.


Central European Journal of Medicine | 2009

Coronary artery bypass graft surgery in the elderly patients

Gursel Levent Oktar; Veli Yildirim Imren; Dilek Erer; Erkan Iriz; Levent Gökgöz; Halim Soncul

The purpose of this retrospective study was to determine the results of coronary artery surgery in the elderly patients and to compare the outcome with a younger group. Two hundred thirteen patients aged 70 years and older who underwent on-pump coronary artery surgery were retrospectively studied and data were compared with those of 524 patients aged 50–69. The groups were similar with respect to preoperative characteristics except for sex distribution and the incidences of peripheral vascular disease and prior cerebrovascular accident. The use of internal mammarian artery grafts was significantly lower in the elderly patients (80.3% versus 91.6%, p<0.001). The 30-day mortality for the elderly group was 4.7% while that of younger group was 2.3%. The elderly patients had a significantly higher incidence of postoperative low cardiac output, pulmonary complications and acute renal failure. The elderly group also had also significantly longer intensive care unit length of stay (1.9 versus 1.7 days, p=0.006) and postoperative length of stay (10.1 versus 7.4 days, p<0.001). Although mortality and complication rates are higher, coronary artery surgery can be performed with acceptable risk in the elderly patients. Old age alone should not be a deterrent factor for surgical revascularization in coronary artery disease.


Journal of Surgical Research | 2014

The effects of iloprost on ischemia-reperfusion injury in skeletal muscles in a rodent model

Tuba Avci; Dilek Erer; Ayşegül Küçük; Yasin Öztürk; Murat Tosun; Gursel Levent Oktar; Mustafa Arslan; Erkan Iriz; Mustafa Kavutcu; Tolga Tatar

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