Effect of learning curve on the perioperative course of robotic-assisted laparoscopic donor nephrectomy compared with laparoscopic donor nephrectomy.

OBJECTIVE: This study was designed to compare the standard and robotic-assisted laparoscopic donor nephrectomy in terms of perioperative course, short-term postoperative outcome, and to evaluate the effect of surgeon's learning curve on these parameters. METHODS: This was a prospective randomized study including 60 patients (mean age, 47 years; age, 21-72 years; 26 males, 34 females) who had been planned laparoscopic donor nephrectomies in our clinic. For comparison of standard and robot-assisted techniques and to evaluate the impact of learning curve, patients were randomized into three groups by a computer, each group containing 20 patients. Group 1: standard laparoscopic donor nephrectomies; Group 2: the first 20 patients who underwent robot-assisted laparoscopic donor nephrectomy; and Group 3: the next 20 patients who underwent robot-assisted laparoscopic donor nephrectomy. RESULTS: Operative time was significantly higher in Group 2 (221.0±45.1 min) than both Group 1 (183.5±16.9 min, p=0.001) and Group 3 (186.5±20.6 min, p=0.002). Similarly, time for laparoscopic system setup was significantly higher in Group 2 (39.5±8.6 min), which contained the first cases of robot-assisted laparoscopic donor nephrectomy where surgeon had least experience than Group 1 (19.3±3.7 min, p<0.001) and Group 3 (24.0±9.4 min, p<0.001). On the other hand, duration of operation and time for laparoscopic system setup was similar between Groups 1 and 3. CONCLUSIONS: Learning curve extends the operative time and laparoscopic system setup time in robotic-assisted laparoscopic donor nephrectomy, however, after the learning process was completed, these parameters were similar between robotic-assisted and standard laparoscopic nephrectomy.

Effect of learning curve on the perioperative course of robotic-assisted laparoscopic donor nephrectomy compared with laparoscopic donor nephrectomy

Summary OBJECTIVE: This study was designed to compare the standard and robotic-assisted laparoscopic donor nephrectomy in terms of perioperative course, short-term postoperative outcome, and to evaluate the effect of surgeon's learning curve on these parameters. METHODS: This was a prospective randomized study including 60 patients (mean age, 47 years; age, 21-72 years; 26 males, 34 females) who had been planned laparoscopic donor nephrectomies in our clinic. For comparison of standard and robot-assisted techniques and to evaluate the impact of learning curve, patients were randomized into three groups by a computer, each group containing 20 patients. Group 1: standard laparoscopic donor nephrectomies; Group 2: the first 20 patients who underwent robot-assisted laparoscopic donor nephrectomy; and Group 3: the next 20 patients who underwent robot-assisted laparoscopic donor nephrectomy. RESULTS: Operative time was significantly higher in Group 2 (221.0±45.1 min) than both Group 1 (183.5±16.9 min, p=0.001) and Group 3 (186.5±20.6 min, p=0.002). Similarly, time for laparoscopic system setup was significantly higher in Group 2 (39.5±8.6 min), which contained the first cases of robot-assisted laparoscopic donor nephrectomy where surgeon had least experience than Group 1 (19.3±3.7 min, p<0.001) and Group 3 (24.0±9.4 min, p<0.001). On the other hand, duration of operation and time for laparoscopic system setup was similar between Groups 1 and 3. CONCLUSIONS: Learning curve extends the operative time and laparoscopic system setup time in robotic-assisted laparoscopic donor nephrectomy, however, after the learning process was completed, these parameters were similar between robotic-assisted and standard laparoscopic nephrectomy.

The relationship between left ventricular mass index and body composition in new-diagnosed hypertensive patients.

BACKGROUND: Cardiovascular disease (CVD) is considered a public health burden and most common cause of mortality in all over the world. The latency time for developing CVD may be several decades. the objective of this study was to examine the relationship between body composition and Left Ventriculare Mass Index (LVMI) in newly diognosed hypertensive patients. METHODS: We enrolled 120 new-diagnosed hypertensive patients (mean age 45 ± 8 years) who admitted to our nephrology clinic. Body fat percentage (BFP) was measured by bioelectrical impedance (BIA). Echocardiography examinations were performed for all patients. RESULTS: Mean values of Waist hip ratio, Body mass index, Body fat percentage, Systolic blood pressure, Diastolic blood pressure were significantly higher for females than males (all p values <0.05). The female patients had higher LVMI than male patients (94.8 ± 13.1 vs 89.2 ± 14.6, p < 0.05). The study patients were divided into 3 groups according to their BFP defined by BIA. Group 3 patients, who exhibited higher body fat, had significantly higher BMI (p < 0,05), total leukocyte count (p < 0.05), CRP (p < 0.05), triglyceride (p < 0.05), and female predominance. Group 3 patients were statistically older than group 1 patients (46.2 vs. 40.6 years, p < 0.05). Additionally, LVMI levels were higher in Group 3 than Group 1 (p < 0.05) (Table 3). In logistic regression analysis, independent factors affecting LVMI were age, weight, gender and BFP (all p values were <0.05). CONCLUSIONS: BFP was associated with higher LVMI, in newly diognosed hypertensive patients. Its use results in significantly lower proportions of individuals with LVH in the population, in particular among hypertensive and the obese patients.

Straight versus S-shaped sternotomy: a histologic study in the sheep model.

INTRODUCTION: Straight sternotomy is the most common access for open heart surgery. Techniques have been proposed for maximizing sternal stability in high-risk patients. This trend implies a growing need for newer surgical techniques. The aim of this experimental study in the sheep model is to evaluate median vs. S shaped sternotomy the feasibility of using a special device to accelerate the sternal instability and bone healing. MATERIALS AND METHODS: We enrolled 31 sheep, weighing 18-30 kg. For all animals a midline skin incision was made. In group I (n = 16 animals), straight median sternotomy and in group II (n = 15 animals), S-shaped incision was marked on the periosteum of the sternum by new created device for standard S-shaped sternotomy. Sternum biopsies were performed on second surgery month for all survived animals from the sternum and the surrounding soft tissue. RESULTS: No early superficial wound complications were observed. Overall mortality in the initial approach group was 19.3% (6 sheep). In group I; 3 sheep had died on first surgery day, the reason may be hemorrhage and in group II; 3 sheep developed intractable VF during surgery procedure or immediately afterwards so died. There were statistically significant differences in the scores of bone healing between group 1 and group 2 (4.2 vs.7.3, ANOVA, p < 0.001). DISCUSSION: Our work is based on the use of a standard S-shaped sternotomy procedure on sheep sternum. In our experience with the sternal healing in the sheep model, the process of new bone formation was accelerated with S- shaped cut than straight sternotomy procedure.

Allopurinol reduces cardiovascular risks and improves renal function in pre-dialysis chronic kidney disease patients with hyperuricemia.

To determine the effect of hyperuricemia and allopurinol therapy on renal functions in chronic kidney disease (CKD) stage 3-4, we studied 96 patients in stage 3-4 CKD (57% male, age 65.3 ± 12.4 years). The mean estimated glomerular filtration rate (GFR) was 44.62 ± 14.38 iriL/ min/1.73 m 2 . The study patients were divided into non-allopurinol users (n = 47) and those using allopurinol (n = 49) in the last 12 months. Serum uric acid (UA) and C-reactive protein levels decreased after allopurinol therapy (P = 0.00 and P = 0.04, respectively), but no change was observed in the control group during the study period. In the allopurinol group, the mean GFR increased 3.3 ±1.2 mL/min/1.73 m 2 /year, while it decreased 1.3 ± 0.6 mL/min/1.73 m 2 in the control group during the follow-up period (P = 0.04); the patients in the allopurinol group exhibited lower levels of serum potassium, serum low-density lipoprotein (LDL) and renal resistance index (RRI) (P-values were <0.05). The patients with stable renal functions or GFR change <10% (n = 25) at the end of 12 months had significantly lower LDL and RRI values and more allopurinol users than the group with decreasing GFR (74% vs. 48%, P <0.05). In the regression analysis, UA and RRI were found as independent variables (r 2 = 0.68, P <0.01; r 2 = 0.25, P <0.01) that affected loss of renal function. We conclude that our study suggests a role for allopurinol, an effective agent in lowering serum UA levels, as a reliable therapeutic option in controlling renal progression in pre-dialysis CKD patients.

Accumulation of an endogenous inhibitor of nitric oxide synthesis and oxidative DNA damage in end-stage renal disease.

BACKGROUND: Elevated oxidative status and reduced antioxidant defence systems in patients with chronic renal failure (CRF) accelerate the prevalence of atherosclerosis and other chronic complications. We aimed to investigate the levels of reactive oxygen, nitrogen species, and antioxidants in patients with end-stage renal disease (ESRD) having hemodialysis and controls and evaluate the factors that might influence the oxidative-antioxidative balance. METHODS: Sixty four patients with ESRD were enrolled in this study. Twenty two controls with normal renal function were included. 8-hydroxy-2'-deoxyguanosine, asymmetric dimethylarginine, and nitrotyrosine levels were quantitated by Elisa. Catalase was assayed with a colorimetric method. Glutathione, nitric oxide, total antioxidant capacity, and lipid hydroperoxide were assayed spectrophotometrically. RESULTS: 8-hydroxy-2'-deoxyguanosine, asymmetric dimethylarginine, nitrotyrosine, and nitric oxide levels of patients were higher than those of the control group (p < 0.01) (p < 0.001), respectively. Total antioxidant capacity and catalase activity were significantly increased in controls compared to patients with renal failure (p < 0.001) (p < 0.01), respectively. CONCLUSIONS: Our data confirmed the previous findings that an increase in oxidative stress may be considered as one of the major risk factors in CRF patients. The lowering of total antioxidant defences in patients with end-stage renal disease on hemodialysis may contribute to the increased oxidative damage and to the development of renal complications.

The relationship of visfatin levels with insulin resistance and left ventricular hypertrophy in peritoneal dialysis patients.

BACKGROUND/OBJECTIVES: Cardiovascular abnormalities are common in patients with chronic kidney disease. Visfatin influences lipid metabolism, insulin sensitivity, and cardiovascular health. The aim of this study was to explore the relation of serum visfatin to cardiovascular risk factors in nondiabetic peritoneal dialysis (PD) patients. PATIENTS AND METHODS: Eighty-seven nondiabetic patients (mean age 48 ± 15 years, 39 males) under PD were enrolled. Weight, anthropometric measurements, blood pressure, biochemical parameters, and insulin resistance (homeostatic model assessment-insulin resistance-HOMA-IR) were measured. Visfatin was measured and left ventricular mass index (LVMI) was calculated by echocardiography. RESULTS: LVMI was correlated with body mass index (BMI; r = 0.47, p = 0.01), systolic blood pressure (SBP; r = 0.62, p = 0.04), and serum visfatin levels (r = 0.49, p = 0.03). According to HOMA-IR levels patients were grouped as insulin-resistant (IR) (HOMA-IR ≥2.0, n = 35) and noninsulin-resistant (non-IR) (HOMA-IR <2.0, n = 52) groups. The IR group had longer PD duration and higher BMI, total cholesterol, uric acid, and serum visfatin levels (p < 0.05). The study patients were divided into three groups according to their serum visfatin levels. Group 1 (≤34 ng/mL, n = 22) was considered as the lowest tertile of low visfatin and group 2 (35-42 ng/mL, n = 43) and group 3 (≥43 ng/mL, n = 22) in the upper tertile. Considering the visfatin groups, group 3 patients had significantly higher BMI (p = 0.00), total cholesterol (p = 0.03), C-reactive protein (CRP) (p = 0.03), HOMA-IR (p = 0.03), and LVMI (p = 0.02). In regression analysis, SBP (ß = 0.19, p < 0.05) and serum visfatin levels (ß = 0.74, p < 0.05) were independent variables affecting LVMI. CONCLUSION: Serum visfatin might be a sensitive marker than HOMA-IR evaluations for cardiac performance in nondiabetic PD patients.

Increased cardiac troponin T levels are related to inflammatory markers and various indices of renal function in chronic renal disease patients.

BACKGROUND/OBJECTIVES: Cardiovascular disease begins early in the course of chronic kidney disease (CKD), and the glomerular filtration rate (GFR) is an independent risk factor for it. There is little information on cardiac troponin concentrations in patients with CKD who have not commenced dialysis. Factors associated with this deleterious process are not completely understood, and we aimed to determine associated laboratory abnormalities of increased cardiac troponin T (cTnT) in patients with CKD. METHODS: In this study, 104 patients (65 males and 39 females with mean age of 65 ± 15 years) were recruited. A detailed clinical history was recorded and routine biochemical variables and cTnT levels were measured. GFR was estimated (44.62 ± 14.38 mL/min/1.73 m(2)) using the modification of diet in renal disease study formula. RESULTS: cTnT is correlated with blood urea (r = 0.262, p < 0.05), uric acid (r = 0.399, p < 0.001), blood phosphorus (r = 0.550, p < 0.001), triglyceride (r = 0.329, p = 0.011), C-reactive protein (CRP; r = 0.768, p < 0.001), renal resistive index (RRI; r = 0.412, p = 0.017), and GFR (r = -0.755, p = 0.011). On stepwise multiple regression analysis, increased CRP (≥12 mg/L), uric acid (≥5 mg/L), and RRI (≥0.70) were independent variables for increased cTnT status (r(2) = 0.053, p < 0.05). CONCLUSION: Increased cTnT not only shows ongoing inflammation but also is a sensitive marker of functioning renal mass. It is strongly correlated with factors influencing the decline in renal function; thus, it can be used as a renal risk parameter.

Association of conicity index and renal progression in pre-dialysis chronic kidney disease.

BACKGROUND/OBJECTIVES: Abdominal fat deposition is represented by means of the conicity index (CI), an anthropometric estimate that models the relative accumulation of abdominal fat. We examined the influence of markers of cardiovascular disease in terms of inflammation and lipid profile and body fat distribution on the progression of renal disease in patients with stable chronic kidney disease (CKD) stages 3-5. MATERIAL AND METHODS: We studied 104 pre-dialysis CKD patients (64 males, 62%; age 64.6 ± 14.7 years). Glomerular filtration rate (GFR) was estimated (44.62 ± 14.38 mL/min/1.73 m2) by modification of diet in renal disease formula. GFR values were estimated at baseline and at the end of the 12-month follow-up. Patients were stratified into three groups: group 1 had a loss of GFR ≥20%; group 2 had a loss of GFR 10-20%; and group 3 patients had stable renal functions or GFR change <10% at the end of 12 months. Body mass index (BMI), waist/hip ratio (WHR), and CI were subsequently computed. Renal resistive index (RRI) was measured using Doppler ultrasonography. RESULTS: CI was strongly correlated with total cholesterol (r = 0.37, p < 0.01), low-density lipoprotein (LDL) (r = 0.53, p < 0.01), C-reactive protein (r = 0.21, p < 0.05), and serum potassium (r = 0.216, p < 0.02), whereas BMI and WHR were not associated with these parameters. The values of CI, serum cholesterol, LDL, alkaline phosphatase, alanine aminotransferase, lactate dehydrogenase activity, the degree of proteinuria and microalbuminuria, and RRI were significantly lower in group 3. In linear regression model, LDL (r2 = 0.17, p = 0.02), uric acid (r2 = 0.19, p < 0.01), and RRI (r2 = 0.64, p < 0.01) were independently associated with CI for all groups. CONCLUSION: CI is an independent predictor of systemic inflammation, cardiovascular risk, and GFR in patients during the pre-dialysis period.

Insulin resistance and left ventricular mass in non-diabetic hemodialysis patients.

BACKGROUND: Insulin resistance (IR) is frequently recognized in patients with uremia, and it is thought that IR has a basic role in the pathogenesis of cardiovascular disease. OBJECTIVE: To evaluate the effect of IR on cardiovascular risk in non-diabetic patients receiving hemodialysis (HD). METHODS: We performed a cross-sectional observational study that comprised 186 non-diabetic patients receiving HD (95 men; mean [SD] age, 46.4 [10.8] years; age range, 35-60 years) who had been receiving HD for 7.3 (3.5) years. Demographic variables and laboratory values were recorded. Insulin resistance was determined using the Homeostatic Model Assessment (HOMA), and the left ventricular mass index (LVMI) was calculated via echocardiography. RESULTS: According to HOMA-IR levels, patients were categorized as having IR (HOMA-IR score ≥2.5; n = 53) or not having IR (HOMA-IR score <2.5; n = 133). Insulin resistance was determined in 28.4% of study patients. Compared with the non-IR group, the IR group had been receiving HD longer; had greater body mass index; and had higher serum creatinine, uric acid, triglyceride, insulin, and C-reactive protein concentrations, leukocyte count, and LVMI (P < 0.05). Patients with increased LVMI had significantly higher body mass index, systolic blood pressure, serum cholesterol and C-reactive protein concentrations, and HOMA score. At multivariate analysis, systolic blood pressure (ß = 0.22; P = 0.03) and HOMA score (ß = 0.26; P = 0.01) affected LVMI. CONCLUSIONS: Insulin resistance and hypertension are independent risk factors for left ventricular hypertrophy in non-diabetic patients with uremia who are receiving HD. Further studies are needed to indicate the benefits of improving IR for cardiovascular mortality in this subgroup of patients with uremia.

Body fat percentage as a risk factor for atherosclerosis but not for inflammation for hemodialysis patients: differences between genders.

INTRODUCTION: Atherosclerosis (AS) and malnutrition are 2 major causes of morbidity and mortality in hemodialysis (HD) patients. A high body fat percentage (BFP) may be paradoxically associated with improved survival in chronic HD patients. We aimed to establish BFP profile of the HD patients by using bioimpedance analysis, body mass index (BMI), and waist/hip ratio (WHR) to find out their association with inflammation and AS. METHODS: In total, 125 HD patients (64 male, 51% mean age of 49.7 ± 12.3 years) were included in the study. Malnutrition-inflammation score (MIS) has been used and supported with biochemical parameters: C-reactive protein, serum iron, total iron binding capacity, ferritin, complete blood count, serum albumin, total cholesterol, low- and high-density lipoproteins, and triglyceride. The patients were divided into 3 groups according to their BFP that were defined by bioimpedance analysis. We also compared these groups according to BMI percentiles. Independent variables affecting BMI and MIS were identified by logistic regression analysis. RESULTS: AS was correlated with high BFP for our female HD patients, but not for the males. BFP, BMI, and WHR were significantly higher for females. Older age (P = .02), BMI (P < .01), WHR (P < .01), total leukocyte count (P = .02), serum iron (P < .01), and total iron-binding capacity (P = .02) were found significantly correlated with higher BFP for female HD patients, whereas only BMI (P < .01) and serum creatinine levels (P = .04) were significant for male patients. In logistic regression analysis, independent factors affecting cardiovascular disease (CVD) were gender, BFP, MIS, and lymphocyte/leukocyte ratio. Independent factors affecting MIS were gender, BFP, CVD, serum albumin level, and serum C-reactive protein. CONCLUSION: BFP and male gender may be contributing factors for CVD; however, female HD patients with high BFP had higher risk of CVD than male counterparts. Further studies are needed to evaluate the pathophysiology of this discrepancy between genders.