Biomedical subjects

H Karakayali

Publications and source records attributed to H Karakayali.

At least 37 records · Page 2Linked to original sources

PubMed2006

Stent placement in pediatric patients with hepatic artery stenosis or thrombosis after liver transplantation.

Hepatic artery stenosis (HAS) and thrombosis (HAT) after orthotopic liver transplantation remain significant causes of graft loss. Postoperative HAT follows approximately 5% to 19% of orthotopic liver transplantation. It is seen more frequently in pediatric patients. In the past, repeat transplantation was considered the first choice for therapy. Recently, interventional radiological techniques, such as thrombolysis, percutaneous transluminal angioplasty, or stent placement in the hepatic artery, have been suggested, but little data exist related to stent placement in the thrombosed hepatic artery during the early postoperative period in pediatric patients. Between March 2000 and March 2005, percutaneous endoluminal stent placement was performed in seven pediatric liver transplant patients. HAT or HAS initially diagnosed in all cases by Doppler ultrasound then confirmed angiographically. We intervened in four cases of hepatic artery stenosis and three cases of hepatic artery occlusion. Stents were placed in all patients. Three ruptures were seen during percutaneous transluminal angioplasty of the hepatic artery using a covered coronary stents on the first, fifth day, or 17th postoperative day. In one patient, dissection of the origin of the common hepatic artery developed owing to a guiding sheath, and a second stent was placed to cover the dissected segment. The other two hepatic artery stents remained patent. In one stent became occluded at 3 months after the intervention with no clinical problems. Follow-up ranged from 9 to 40 months. In conclusion, early and late postoperative stent placement in the graft hepatic artery was technically feasible.

Adolescent↗

PubMed2005

Comparison of two different percutaneous splenic artery interventions in the treatment of hypersplenism: preliminary report.

BACKGROUND: Splenomegaly and hypersplenism occur in patients with chronic liver disease and liver transplant recipients. The traditional treatment for hypersplenism is surgical removal. Percutaneous interventional methods, such as partial splenic embolization, are alternatives to surgery for hypersplenism. This article gives preliminary findings for a new percutaneous technique in which a narrowed stent is placed in the splenic artery. METHODS: The study focused on 10 patients (eight males and two females) who were treated for hypersplenism. Partial splenic embolization was performed in six patients (age range, 1-43 years) who were waiting for liver transplantation, and narrowed stents were placed in four patients (age range, 12-47 years) who had undergone either orthotopic two patients) or heterotopic two patients) liver transplantation. For embolization, the splenic artery was catheterized and polyvinyl alcohol particles were infused to the distal branches, reducing blood flow in the spleen by 40% to 50%. In the other cases, a narrowed stent was deployed to the middle portion of the splenic artery. RESULTS: Hypersplenism was successfully treated in all 10 cases. Compared with partial splenic embolization, placement of narrowed stents was associated with lower frequencies of postintervention fever and pain, shorter hospital stay, and decreased need for antibiotics. In addition to treating hypersplenism, narrowed-stent placement also completely resolved splenic artery steal syndrome in the two patients (orthotopic liver transplant recipients) with this condition. CONCLUSION: Percutaneous placement of a narrowed stent in the splenic artery is a promising new technique for treating hypersplenism and splenic arterial steal syndrome.

Adolescent↗

PubMed2005

The effect of anesthetic technique on early postoperative renal function after donor nephrectomy: a preliminary report.

General and regional anesthesia may both be used successfully in donor nephrectomy although the use of regional anesthesia is rare. We compared the remaining kidney function during general (n = 10) versus combined spinal-epidural (n = 10) anesthesia for donor surgery. Blood biochemistry data were collected preoperatively and postoperatively, while renal function was assessed by scintigraphy and urine levels of microalbumin, creatinine, Na, K, Ca and creatinine clearance rate were measured/calculated in 24-hour urine samples collected preoperatively and on postoperative day 2. There were no differences preoperatively and on postoperative day 2 with respect to glomerular filtration rate, microalbuminuria, or creatinine clearance rate (P > .05 for all). There were also no differences between the groups with respect to other scintigraphic findings preoperatively and on postoperative day 2 (P > .05 for all). The results suggest that general or combined spinal-epidural anesthesia for donor nephrectomy have similar effects on the remaining donor kidney function.

Anesthesia, Epidural↗

PubMed2005

Liver transplantation and tacrolimus monotherapy for hepatocellular carcinoma with expanded criteria.

Liver transplantation is the only curative treatment option for patients with cirrhosis and unresectable hepatocellular carcinoma (HCC) without extrahepatic dissemination. Criteria for transplantation in HCC are controversial. In this study, we evaluate the early results of liver transplantation for unresectable HCC. Between 2003 and 2004, 10 patients (three woman, seven men; aged 1.1 to 64 years) with occult or incidental HCC underwent liver transplantation. The inclusion criteria (independent of tumor size and number of tumor nodules) were: no invasion of major vascular structures and no evidence of extrahepatic disease, including that based on hilar lymph node biopsy and cytopathological examination of intraperitoneal fluid. Eight patients (80%) received tacrolimus and two patients (20%) received rapamycin monotherapy with early withdrawal of the corticosteroid. Four patients had neoadjuvant chemoembolization before transplantation. None of the patients received adjuvant chemotherapy. Two patients with hepatitis B virus cirrhosis underwent antiviral prophylaxis with anti-HBs antibody and lamivudine. During follow-up (range, 8 to 19 months), all patients did well with excellent graft function. There was no evidence of tumor recurrence on imaging studies, and there were no elevations in alpha fetoprotein or carcinoembryonic antigen levels. Low-dose immunosuppression and expanded criteria for liver transplantation for HCC appear to have beneficial effects on disease recurrence and patient outcomes, especially in regard to living donation.

Adolescent↗

PubMed2005

Living-related liver transplantation in pediatric patients.

INTRODUCTION: Many developments in surgical technique, immunosuppression, and patient selection criteria have led to improved long-term patient and graft survival in pediatric patients receiving liver transplants. In this study, we examined the early results of 26 pediatric recipients who underwent 26 liver transplantations between January 2003 and December 2004 at our institution. MATERIALS AND METHODS: The most common indications for liver transplantation were cholestasis in 10 patients (38.5%) and Wilson's disease in 8 (30.8%). Other indications were fulminant hepatic failure (4 patients, 15.4%), tyrosinemia (2 patients, 7.7%), Caroli disease (1 patient, 3.8%), and cryptogenic cirrhosis (1 patient, 3.8%). One recipient with Byler disease and two with tyrosinemia also had incidental hepatocellular carcinoma. RESULTS: Of 26 patients, 24 (92.3%) underwent living-related liver transplantation and 2 (7.7%) underwent cadaveric transplantation. The medical records of all patients were retrospectively reviewed. Twenty-two of 26 survived with excellent graft function, showing 91.2%, 86.4%, and 81.6% at 3, 12, and 24 months graft and patient survival rates, respectively. Sixteen patients (61.5%) developed various morbidities with biliary and vascular complications being the most common. Four patients (15.3%) developed bile leaks. Four patients (15.3%) developed hepatic artery thromboses. Five patients (19.2%) developed life-threatening infections. Four patients (15.4%) died during the study period, three owing to infectious complications. The other patient died due to acute respiratory distress syndrome. CONCLUSION: Despite technical difficulties and a donor organ shortage, the results of liver transplantation in pediatric patients with end-stage liver disease have demonstrated promising results at our institution.

Adolescent↗

PubMed2005

Influence of HLA compatibility on success with living-related pediatric liver transplantation.

It is not clear how HLA compatibility influences acute rejection and postoperative complications in cadaveric liver transplantation. Even less is known about this factor in pediatric living-related liver transplantation (LRLT). This research assessed HLA compatibility relative to rejection rates and complications in pediatric LRLT. The study retrospectively investigated data from 14 pediatric LRLTs in which the donor and recipient HLA genotypes were determined preoperatively. Three recipients (21.4%) developed biliary complications (two biliary leakage, one bile duct stenosis). Three others (21.4%) developed vascular complications (two hepatic artery thrombosis, one hepatic artery stenosis). Eight recipients (57.1%) were diagnosed with acute rejection. The incidence of acute rejection was not correlated with the number of HLA mismatches (P > .05), or with the number of HLA class I mismatches (P > .05); however, it was negatively correlated with number of HLA class II mismatches (P = .02). Arterial and biliary complications were not correlated with any of these categories of HLA compatibility. In conclusion, the data from this small group of patients provided no evidence that closeness of donor-recipient HLA matching influences outcome in pediatric LRLT.

Adolescent↗

PubMed2005

The effect of graft nephrectomy on long-term graft function and survival in kidney retransplantation.

We retrospectively evaluated the long-term results of 53 (3.5%) recipients who received second allograft among 1486 kidney transplants between November 3, 1975 and June 30, 2004. Two study groups were patients in Group 1 (n = 21) who underwent allograft nephrectomy and those in Group 2 (n = 32) who did not. We assessed demographic features, rejection rates throughout the follow-up period, and serum creatinine levels at 12 months as well as graft and patient survival rates, postoperative complications, time interval between transplantations, and HLA matches. Forty-three patients who underwent retransplantation received kidneys from living-related donors and the remaining 10 from cadaveric donors. Mean serum creatinine levels of Group 1 versus Group 2 were 1.8 mg/dL (range, 0.8 to 6.6 mg/dL) versus 2.1 +/- 1.1 mg/dL (range, 1.1 to 7.1 mg/dL). HLA-AB and HLA-DR mismatches were 1.9 +/- 1.1 versus 1 +/- 0.6, respectively (P = .01). Acute rejection rates were not significantly different between Groups 1 (9/21, 43%) and 2 (12/32, 38%) (P < .05). The average intervals between the first and the second transplantations were 62 +/- 26 months in Group 1 (P = .02) and 32 +/- 11 months in Group 2. One-, 3-, and 5-year graft survival rates in Group 1 versus Group 2 were 83% versus 89% (P > .05); 64% versus 79% (P > .05), and 45% versus 68% (P = .04), respectively. In conclusion, we did not observe any advantage of graft nephrectomy before retransplantation. The length of the interval between the first and the second transplantations may have a negative correlation with second graft survival.

Adolescent↗

PubMed2005

Biliary complications and their management in pediatric liver transplantations: one center's experience.

Following living-donor liver transplantation, biliary complications are more prevalent among pediatric patients (<18 years old), with reported rates varying between 15% and 30%. In this study, we retrospectively analyzed biliary complications observed in 21 pediatric liver transplant patients (16 boys [76.2%], 5 girls [23.8%] of ages 1 to 18 years (mean, 8.3 +/- 5.05 years) between September 2001 and June 2004. Biliary reconstruction was accomplished via a duct-to-duct anastomosis in 12 (57.1%) and a Roux-en-Y hepaticojejunostomy in 9 (42.9%) patients. Postoperative biliary complications were encountered in six (28.5%) patients. Four of the biliary leaks were from a duct-to-duct anastomosis and two from an hepaticojejunostomy. One (4.7%) patient who experienced biliary leakage after a duct-to-duct anastomosis developed stenosis after the leak healed; five (23.8%) had the leakage treated successfully. One patient had biliary leakage from the duct-to-duct anastomosis subsequent to a hepatic artery thrombosis. All patients with biliary leakage were treated without surgery. Mean follow-up time was 10.2 +/- 9.6 months (range, 1 to 26 months). Three patients died during follow-up; however, these deaths were not related to the biliary complications. Interventional radiologic approaches are effective to biliary complications, even when the anastomoses are heavily disrupted. In cases of biliary complication, percutaneous combined with internal drainage may prevent biliary sepsis and provide long-term patency.

Adolescent↗

PubMed2005

The history and activities of transplantation in Turkey.

The cornerstone events of transplantation history in Turkey are summarized herein. In 1975, we performed the first living-related renal transplant in Turkey. This was followed in 1978, by the first deceased donor kidney transplantation, using an organ supplied by Eurotransplant. In 1979 the law on harvesting, storage, grafting, and transplantation of organs and tissues was enacted; later that year, the first local deceased donor kidney transplantation was performed by our team. In 1988, another groundbreaking event in Turkey was successfully achieved; the first cadaveric liver transplantation; and in 1990, the first pediatric living-related segmental liver transplantation in Turkey and in the region by our team. One month later, an adult-to-adult living-related liver transplantation was successfully performed. Until now, we have performed 1506 kidney and since 1988, 121 liver transplantations. During 29 years of solid organ transplantation history in Turkey, 6686 kidney transplants have been performed nationwide in 28 different centers; 696 livers; 13278 corneas; 2883 bone marrow; 132 hearts; and 15 pancreas transplants. In 2001, the health ministry established the National Coordination Center as an umbrella organization to promote transplantation activities, especially for deceased donor organ procurement. Transplantation activities are accelerating day by day all around the country, but deceased donors are still far below the desired rates. Improvements in the fields of education and coordination should increase the quality and the quantity of transplantation activities.

Adult↗

PubMed2005

Duct-to-duct biliary anastomosis with a "corner-saving suture" technique in living-related liver transplantation.

OBJECTIVES: Biliary complications after living-related liver transplantation (LRLT) remain a major source of morbidity for recipients. We describe our technique and early results with 32 recipients who underwent LRLT with duct-to-duct anastomoses during the last 2 years. METHODS: Between January 2003 and December 2004, 50 patients underwent liver transplantation in our center with overall patient and graft survival rate of 86.4% and 86.4%. Of 50 patients, 41 (82.0%; 17 adult and 24 pediatric) underwent LRLT, 32 (78.0%) of whom had duct-to-duct biliary anastomoses with a "corner-saving suture" technique. RESULTS: Of 32 patients in whom duct-to-duct biliary anastomoses were performed, 4 (12.5%) had an anastomotic leak with 2 eventually developing bile duct strictures within 3 months. One patient required reoperation for a bile leak. All other anastomotic leaks and strictures were treated with percutaneous drainage and balloon dilatation with excellent outcomes. There was no long-term morbidity and no graft loss owing to biliary complications. Seven patients died during follow-up (0.5 to 25 months); 43 are doing well with optimal liver function in the early posttransplantation period. CONCLUSION: According to our early results, we recommend duct-to-duct anastomosis in LRLT when calibration of the ducts show suitable results and when there is no tension on the anastomosis site. Otherwise, Roux-en-Y hepaticojejunostomy should be performed to decrease risk of biliary complications.

Anastomosis, Surgical↗

PubMed2004

Comparison of hemodynamic changes associated with two different polytetraflouroethylene arteriovenous fistulae in hemodialysis patients.

The aim of this prospective study was to identify hemodynamic factors associated with two different types of polytetrafluroethylene (PTFE) AV grafts. The study was conducted on 46 hemodialysis patients over a 3-year period. The subjects were randomly assigned to one of two study groups: Group 1 patients (n = 24) underwent a brachiocephalic loop PTFE fistula; Group 2 patients (n = 22), a brachioaxillary PTFE fistula. Preoperatively, we recorded each individual's subclavian catheter history, hemodialysis frequency, and serum levels of parathormone (PTH), calcium (Ca)-phosphorus (P) product, homocysteine, protein C, and protein S. Doppler ultrasonography was used to evaluate vascular hemodynamic changes in the proximal and distal portions of the AV fistula at 48 hours and 1 week postoperatively. Group 1 showed a significantly greater number of ipsilateral subclavian catheter interventions prior to AV graft surgery than Group 2 (14 versus 7, respectively; P = .05; chi-square). The mean peak systolic velocity in the brachial artery in Group 1 was significantly higher than that in Group 2 at 1-week postoperatively (P = .04, paired t-test). The mean radial artery diameter in Group 1 was greater than that of Group 2 at 1 week postoperatively (P = .05, Student t-test). At 48 hours postoperatively the observed change in cephalic vein diameter in Group 1 was significantly greater than the change in axillary vein diameter in Group 2 (P = .08, paired t-test). Preoperatively, the mean serum protein C and protein S levels in Group 1 were higher than those in Group 2 (P = .03 and P = .04, respectively; Mann-Whitney U test). The total numbers of dialysis sessions per week in each group were significantly different (P = .001, chi-square). Six Group 1 patients exhibited graft thrombosis at 48 hours after AV graft surgery. None of the patients in Group 2 exhibited thrombosis at 48 hours or 1 week postoperatively. The results indicate that patients with brachiocephalic PTFE AV grafts show more significant changes in the cephalic vein and brachial artery than patients with brachioaxillary PTFE AV grafts. The findings also suggest that more ipsilateral subclavian catheter interventions and a higher weekly frequency of hemodialysis prior to AV graft surgery are risk factors for early thrombosis of PTFE AV grafts.

Adult↗

PubMed2004

Regional versus general anesthesia for donor nephrectomy: effects on graft function.

Various general and regional anesthesia methods are used successfully in living-donor kidney transplantation. This study compared kidney graft function after general versus combined spinal-epidural anesthesia for donor nephrectomy. The study groups included recipients who received grafts from donors who had undergone nephrectomy under general anesthesia (GA group; n=10), and recipients who received grafts from donors who had combined spinal-epidural anesthesia (CSE group, n=10). Standard continuous epidural anesthesia was administered during all transplantations. Graft function was assessed using scintigraphy and Doppler ultrasonography on days 3 and 7. Urine levels of microalbumin, creatinine, and creatinine clearance rate were measured/calculated in 24-hour urine samples collected on postoperative days 3 and 7. There were no differences on either day 3 or day 7 with respect to glomerular filtration rate, microalbuminuria, or creatinine clearance rate (P >.05 for all). There were also no differences between the groups with respect to other scintigraphic findings on day 3 or day 7 (P >.05 for all). Ultrasonography on day 7 showed significantly higher mean peak systolic flow in the main renal artery in the CSE group than in the GA group (P=.035). The results suggest that GA and CSE for donor nephrectomy have similar effects on kidney graft function in recipients.

Adult↗

PubMed2003