An Assessment of the Effects of Two Types of Bioresorbable Barriers to Prevent Postoperative Intra-Abdominal Adhesions in Rats

Purpose This study assessed and compared the efficacy of two types of bioresorbable membranes in the prevention of postoperative adhesion under clean contaminated and bacterial peritonitis conditions using a cecal ligation and puncture model in rats. Methods Wistar albino rats (n = 72) were divided into six groups. Bacterial peritonitis was induced using a cecal ligation and puncture model in groups 2, 4, and 6. Groups 1, 3, and 5 served as controls for clean contaminated procedures in the absence of bacterial peritonitis. Groups 1 and 2 were the untreated clean contaminated and bacterial peritonitis groups and served as controls for the effect of the bioresorbable membranes in each condition. In groups 3 and 4, a 1.5 × 3 cm USP glycerol/sodium hyaluronate/carboxymethylcellulose membrane was wrapped around the cecal resection area and a 2 × 4 cm membrane was left under the incision. The oxidized regenerated cellulose membrane was similarly applied in groups 5 and 6. Four weeks later, the adhesions were evaluated. In addition, fibrosis and inflammation were observed histopathologically. Results Adhesion development (P = .008), fibrosis (P = .008), and inflammation (P = .0001) differed among the groups. Both materials increased adhesion formation in the bacterial peritonitis condition. Increased fibrotic activity was detected in all material-applied groups under both conditions. In addition, more inflammation was detected in the groups that received the application of a material, especially in the presence of bacterial peritonitis. Conclusion Neither material prevented adhesions in clean contaminated conditions. Moreover, they increased adhesion formation in bacterial peritonitis.     

Does the use of a flap during abdominoperineal resection decrease pelvic wound morbidity?

We hypothesized that the use of muscle flaps, known as tissue transfer (TT), at the time of abdominoperineal resection (APR) reduces perineal wound complications. A restrospective review of patients undergoing an APR at the University of Washington (1984-2003) was conducted. Perineal wound complications and eventual wound healing were compared in patients with and without TT. Ninety-two patients (mean age, 56.6 years) underwent APR; 23.9 per cent (n = 22) had concurrent TT. Patients undergoing TT were more likely to have cancer (91% vs. 77%, P = 0.05) and radiation therapy (86% vs. 52%, P < 0.01). Operative times were nearly 2 hours longer in patients having TT (7.4 hours +/- 2.5 hours vs. 5.6 hours +/- 1.8 hours, P = 0.03), but lengths of stay were similar (13 +/- 5.9 days vs. 12 +/- 7.6 days, P = 0.5). Patients undergoing TT had a higher rate of all wound-healing complications (59% vs. 40%, P = 0.1) and major wound-healing complications (32% vs. 26%, P = 0.6). However, these differences were not statistically significant. No differences in major complications were identified in patients with and without preoperative radiation therapy (26% vs. 28%, P = 0.8). Fifteen per cent (n = 14) of all patients failed to heal wounds at 6 months, but only 9 per cent (n = 2) of patients undergoing TT failed to heal their wounds at 6 months compared with 17 per cent (n = 12) in the non-TT group (P = 0.3). After controlling for important covariates, patients undergoing TT during an APR did not have a significantly lower rate of wound complications. The impact of TT on wound healing in patients with recurrent cancer and preoperative radiation therapy is suggestive of a benefit but requires prospective investigation.     

Anatomical variations as potential risk factors for ulnar tunnel syndrome: a cadaveric study

The aim of this study was to assess the anatomical variations, especially the anomalous muscles passing through Guyon's canal and the fibrous arch forming the piso-hamate hiatus, which may play a role in ulnar tunnel syndrome. We have also focused on the relation of these structures with specific concern to the ulnar nerve. Nineteen embalmed cadavers (37 hands and forearms) were dissected. A fibrous arch extending between the pisiform and the hook of the hamate was observed in 21 hands. In majority of the cases flexor digiti minimi muscle was found to originate only from this arch. An anomalous muscle was disclosed in six hands with four of them passing through the piso-hamate hiatus with the deep branch of the ulnar nerve. In two of four cases, the superficial branch of the ulnar nerve was also accompanying the deep branch of the ulnar nerve beneath the anomalous muscle and through the piso-hamate hiatus. Because these anomalous muscles were generally found to course through the piso-hamate hiatus with the branches of the ulnar nerve, we conclude that the distal portion of the Guyon's canal has a relatively higher risk for ulnar nerve entrapment. We believe that surgeons operating on this region should take into account these various anatomic structures.     

Delayed gastric emptying in gastroesophageal reflux disease: the role of malrotation

The association between gastroesophageal reflux (GER) and intestinal malrotation (IM) has been well described. Delayed or impaired gastric emptying in IM is thought to be a contributing factor in the development of gastroesophageal reflux disease (GERD). The current study assessed the role of malrotation in delayed gastric emptying in children with GERD. We also evaluated the interactions between GERD, malrotation, gastric pH abnormalities, and gastric dysmotility. Sixty-seven patients between 1 and 5 years of age (mean 3.08±1.2) and with symptoms of GER, such as emesis, reactive or recurrent lung disease, and/or growth retardation, were studied in 2001–2005. Upper and lower gastrointestinal contrast studies were performed for the diagnosis of malrotation. Gastric motility was evaluated with a liquid gastric emptying protocol. GER was documented by upper gastrointestinal studies, scintigraphy, and/or 24-h pH monitoring. In our series of 44 children with GERD, there was an unexpectedly high incidence of IM: 54.5% (24/44). IM has previously been known to occur in 25% of patients with GERD. GERD was found in 24 (82.7%) of 29 patients with IM. Mean nuclear gastric emptying (MNGE) was 51.6±8.04 min in patients with isolated GERD and 96.6±20.5 min in children with IM and GERD. There was a statistically significant difference in MNGE time (p<0.05) between children with primary GERD and in those with GERD and IM. Esophageal pH monitoring showed that mean fraction time below pH 4 was 7.06±1.1% in patients with isolated GERD and 14.7±4.1% in patients with IM and GERD. GERD is common in children between 1 and 5 years old. Using gastric emptying studies and esophageal pH monitoring, we have shown that gastric dysmotility and esophageal pH abnormalities are highly prevalent, especially in children with malrotation compared with children with isolated GERD. These findings suggest that malrotation is an important factor responsible for delayed gastric emptying in GERD. Hence, we recommend that all infants and children with GERD and delayed gastric emptying undergo careful evaluation for malrotation.     

Does Coronary Artery Size Really Matter?

OBJECTIVE: To evaluate ischemia in right ventricle (RV) in patients with small caliber of right coronary artery (RCA). PATIENTS AND METHODS: The study population consisted of 60 consecutive patients undergoing coronary angiography within 3 months. The patients were divided into three different groups according to lumen diameter of RCA and coronary dominance. Group 1, 2, and 3 consisted of patients with small diameter of RCA, dominant RCA, and dominant circumflex artery, respectively. RV ischemia was assessed by using pulse-wave tissue Doppler sampling obtained from RV free wall close to the lateral tricuspid annulus at the apical four-chamber view during dobutamine stress echocardiography (DSE). RESULTS: When the mean systolic velocity percentages of increase from low to peak dose dobutamine in patients with small RCA were compared to those of other groups, statistically significant difference was found between group 1 and the other groups (P = 0.007 for group 1 vs group 2; P = 0.01 for group 1 vs group 3). The mean systolic velocity at peak dobutamine dose of patients with small caliber of right coronary artery was statistically lower than the other groups (P = 0.001 for group 1 vs group 2, P < 0.001 group 1 vs group 3). CONCLUSIONS: There are a group of patients with small diameter of RCA causing probable ischemia in RV and small caliber of RCA can really matter in these patients.     

Antioxidant properties of propofol and erythropoietin after closed head injury in rats

Reactive oxygen species play a role during brain injury due to closed head trauma. Enzymatic or nonenzymatic antioxidants may protect brain tissue against oxidative damage. The present study was performed to assess the changes of endogenous indices of oxidative stress in serum from rats subjected to head trauma and whether treatment with propofol and/or erythropoietin (EPO) modifies the levels of endogenous indices of oxidative stress. For these purposes, female Wistar Albino rats were divided into five groups: non-traumatic sham group, trauma performed control, trauma with propofol (i.p.), trauma with EPO (i.p.) and trauma with propofol and EPO performed study groups. At the end of the experimental procedure, blood was taken by cardiac puncture to determine superoxide dismutase (SOD) and xanthine oxidase (XO) activities as well as malondialdehyde (MDA) and nitric oxide (NO) levels in serum. Serum MDA level of control traumatic brain injury (TBI) group was significantly higher than sham operation group (p<0.012). Serum MDA levels in propofol, EPO and propofol+EPO groups were found to be decreased in comparison with control group (p<0.039, p<0.030 and p<0.018, respectively). Serum NO level was found to be increased in TBI group, but difference was not statistically significant when compared to sham-operated group (p=0.092). Propofol, EPO and propofol+EPO administration efficiently reduced serum NO levels to reach sham-operated group (p<0.002, p<0.001 and p<0.015, respectively). These results suggested that acute administration of both propofol and EPO altered the indices of oxidative stress similarly against brain injury due to trauma.     

Global fibrinolytic capacity in children on dialysis

Disturbances of coagulation and fibrinolysis have been reported in patients with chronic uremia. Studies of different coagulation and fibrinolysis parameters in regularly dialyzed patients have yielded conflicting results. Global fibrinolytic capacity (GFC) examines the function of the entire fibrinolytic system. This assay is a sensitive and reliable method for evaluating the fibrinolytic function of plasma in vitro. In this study, GFC was used as a screening test to investigate the effects of two different dialysis modalities on the fibrinolytic system on children on long-term dialysis. MATERIALS AND METHODS: The study included 12 children (age range, 11-20 years; mean age, 15.9+/-3.3 years) who were undergoing regular hemodialysis (HD) and 12 children (age range, 10-15 years; mean age, 13.1+/-1.7 years) who were undergoing continuous ambulatory peritoneal dialysis (CAPD). Thirteen healthy age- and sex-matched subjects served as controls. Each sample was investigated for complete blood count and serum levels of C-reactive protein, serum electrolytes, total cholesterol, triglyceride, fibrinogen, total protein and albumin. A GFC assay was also done in each case. RESULTS: The mean GFC in the CAPD group was lower than that in the HD and control groups (p<0.05). There was no significant difference between the mean GFC values of HD patients and controls. The mean serum albumin level was lower in CAPD patients than in HD patients (p<0.05), and there was also a positive correlation between serum albumin level and GFC in patient groups(r=0.52, p<0.05). Global fibrinolytic capacity was positively correlated with hemoglobin level and negatively correlated with weekly erythropoietin dose per kg body weight (r=0.56 and r=-0.49, respectively; p<0.05). CONCLUSION: The results suggest that CAPD patients have decreased fibrinolytic capacity compared to HD patients. Hypoalbuminemia and erythropoietin treatment may contribute to suppression of fibrinolytic function CAPD patients.     

Midterm results of aortic valve repair with the pericardial cusp extension technique in rheumatic valve disease

BACKGROUND: The encouraging results of valve repair in the atrioventricular valves have influenced a decision about aortic valve (AV) reconstruction. We report our experience with pericardial cusp extension to repair rheumatic AV disease. METHODS: From 1993 to 1998, 46 patients (25 women, 21 men) with a mean age of 31.5 +/- 12.2 years (range, 15 to 58 years) underwent AV repair. Twenty-two (47.8%) patients had moderate and 24 (52.2%) had severe aortic insufficiency (AI). Severe cusp retraction was repaired with glutaraldehyde-treated autologous pericardium. Twenty-one patients had more than one maneuver (mean, 1.8) to attain competence besides augmentation, which consisted of the release of stenotic commissures (in 11 cases), thinning of the AV cusps (in 10 cases), and resuspension of the cusps (in 17 cases). Simultaneous mitral valve repair was performed on 17 patients. Eight patients received triple valve reconstruction. RESULTS: There was no early mortality. Thirty patients no longer had AI with any significant transvalvular gradients. Five patients were followed with mild residual AI, and 2 patients with moderate AI not requiring reoperation. Nine patients developing severe AI required AV replacement with a reoperation rate 19.6% (4.26%/patient-year). The mean interval between repair and reoperation was 28.2 +/- 18.3 months (range, 3 to 58 months). The mean observation time was 4.6 +/- 3 years (211.6 patient-years). Late mortality rate was 2.2% with 1 patient. The significant negative predictors of aortic reoperation determined by univariate analysis were preoperative New York Heart Association class (p = 0.002) and postoperative severe AI (p < 0.001). Cox hazard studies identified that all risk factors were insignificant for aortic reoperation. The actuarial rate of freedom from aortic reoperation was 76.1% +/- 7% at 7.5 years. CONCLUSIONS: Although AV repair by extension with pericardium is worth considering with an acceptable solution to achieve a good geometry from unequal cusps, especially in young rheumatic patients for preservation of the native AV, the patients should be followed periodically for reoperation risk.     

Seroprevalence of antibodies to legionella pneumophila in hemodialysis patients

Patients with chronic renal failure are at increased risk for infections because of impaired cellular immunity. This study was designed to determine the prevalence of antibodies to Legionella pneumophila serogroups 1 to 6 and to evaluate the possible risk factors for Legionnaires' disease in hemodialysis patients. Serum samples to be screened for antibodies against L pneumophila and risk factor data were collected from 252 hemodialysis patients. The overall prevalence of L pneumophila antibodies in hemodialysis patients was found to be 5.16% There was no statistically significant difference between L pneumophila seropositivity and potential risk factors. Further studies are needed to determine possible risk factors for Legionnaires' disease in hemodialysis patients.