Fatih Agalar

In vitro S. epidermidis and S. aureus adherence to composite and lightweight polypropylene grafts.

BACKGROUND Despite the significant risk of infection, prosthetic graft materials have become indispensable for incisional hernia repair. Composite and lightweight grafts have been developed to overcome adhesion and rigidity. The aim of this study was to evaluate in vitro S. epidermidis and S. aureus adherence to these new generation grafts, which have modified composition and textile properties. MATERIALS AND METHODS In this experimental study, sterile samples of multifilament polypropylene, multifilament lightweight composite, monofilament composite, and monofilament polypropylene grafts were incubated with slime positive S. epidermidis and S. aureus strains for 24 h. The grafts were washed and vortexed in saline. The saline was passaged to blood agar and incubated for 24 h. The colonies were counted. Naïve and incubated graft materials were examined by scanning electron microscopy to reveal both textile properties and biofilm formation. Physicochemical properties were evaluated. Wilcoxon signed ranks test and Friedman test were used for statistical analysis. RESULTS S. epidermidis showed a significantly decreased adherence to monofilament polypropylene graft, and increased adherence to multifilament polypropylene graft (P<0.05). S. aureus showed a significant affinity for monofilament composite graft (P<0.05). SEM studies showed that biofilm formation was present on multifilament polypropylene graft. CONCLUSIONS Both S. epidermidis and S. aureus had significantly less adherence to multifilament lightweight composite than multifilament polypropylene graft. S. epidermidis showed a greater affinity to monofilament composite graft compared with monofilament polypropylene graft. Overall S. epidermidis adherence for multifilament lightweight composite and monofilament composite was less than multifilament polypropylene and higher than monofilament polypropylene. S. epidermidis and S. aureus showed different adherence for each graft. Changes in material composition and textile properties may well influence bacterial adherence.

Staged Abdominal Repair for Treatment of Moderate to Severe Secondary Peritonitis

The aim of this study was to evaluate the effects of planned relaparotomy and to assess factors that may contribute to mortality in patients with moderate to severe secondary peritonitis. A total of 36 consecutive patients with an Acute Physiologic and Clinical Health Evaluation (APACHE) II score of >10 were enrolled the study for a 2-year period. The mean age of the patients was 56 years (17-92 years), and 23% of them were male. One-third of them had postoperative peritonitis; 152 scheduled operations were done, and the overall mortality rate was 36%. For patients whose septic source was in the upper gastrointestinal system, control of the source was more difficult (p = 0.004). Overall, 28 complications developed in 61% of the patients. Initial and second-day APACHE II scores were 14.5 (11-27) and 12.0 (9-25), respectively. The initial APACHE II score of survivors was lower than that of nonsurvivors [p = 0.0001, 95% confidence interval (CI) -9.5, -3.6]. Second-day APACHE II scores were not different (p = 0.19; 95% CI -3.79, 0.80). Striking end or lateral duodenal leaks were clearly associated with high mortality. It is found that the initial APACHE II score, the success of controlling the source, the occurrence of complications, and the type of illness are independent factors that may affect mortality. We concluded that staged abdominal repair should be used with caution in the treatment of lateral or end duodenal leaks. It is a good alternative to conventional laparotomy for moderate to severe forms of secondary peritonitis from other sources.

Effects of Laparotomy, and Carbon Dioxide and Air Pneumoperitoneum, on Cellular Immunity and Peritoneal Host Defences in Rats

OBJECTIVE To assess the effects of laparotomy, and insufflation of carbon dioxide and air, on the immune system in rats. DESIGN Randomised laboratory study. SETTING Teaching hospital, Turkey. ANIMALS 77 Wistar rats randomly allocated to 2 groups one of which was sensitised with dinitrofluorobenzene (DNFB, n = 43) and one of which was not (n = 34). INTERVENTIONS The DNFB group was sensitised and subdivided into control (n = 8), laparotomy alone (n = 7), and insufflation with carbon dioxide (CO2) for 30 and 60 mins (n = 7 in each) or room air for 30 and 60 mins (n = 7 in each). A week later DNFB was reapplied to the ears. In the group not sensitised with DNFB the animals were subdivided similarly, the corresponding numbers in each group being, 6, 6, 6, 6, 5, and 5. MAIN OUTCOME MEASURES Delayed type hypersensitivity (DTH) measured by ear swelling in the DNFB group, and peritoneal bactericidal activity, total free peritoneal cell counts (TPC), and cell types in the non-sensitised group. RESULTS There were significant differences in the degree of ear swelling in the DNFB group between control and laparotomy groups (p = 0.0001) and between control and both insufflations of air (p = 0.002 and p = 0.0003, respectively). In the non-sensitised group peritoneal bactericidal activity was significantly increased after 7 hours in the 60 mins air insufflation group (p = 0.04). At 24 hours there were no differences among the groups. TPC were not affected. The number of peritoneal polymorphonuclear leucocytes (PMN) was significantly higher in the laparotomy alone group than in the control or any of the insufflation groups (p < 0.05). CONCLUSIONS Laparotomy and air insufflation depressed cell-mediated immunity. Peritoneal bactericidal activity was affected only after 60 minutes of air insufflation.

Similar effects of general and spinal anaesthesia on perioperative stress response in patients undergoing haemorrhoidectomy.

Surgery induces release of neuroendocrine hormones (cortisol), cytokines (interleukin-6: IL-6, tumour necrosis factor-α: TNF-α), acute phase proteins (C-reactive protein: CRP, leptin). We studied the effects of general and spinal anaesthesia on stress response to haemorrhoidectomy. Patients were assigned to general and spinal anaesthesia groups (n = 7). Blood samples were drawn before induction and 24 hours after surgery. Perioperative levels of IL-6, TNF-α, CRP, cortisol, and leptin were comparable among the groups. Twenty four hours after surgery, TNF-α and cortisol did not change; IL-6 and CRP increased significantly in all patients. Significant increase in leptin levels was found in patients undergoing spinal anaesthesia. Except for the increase in leptin levels, there was no significant difference related to the effects of general and spinal anaesthesia.

The effect of lidocaine/prilocaine cream on an experimental wound healing model.

The effects of lidocaine/prilocaine cream on wound healing were evaluated in this study. An incisional wound model on abdominal wall was performed on mice. A full thickness skin incision 2 cm in length was performed then it was sutured primarily with 4/0 polypropylene. In group I (n  = 10) only suturing was done (control group), in group II (n  = 10) lidocaine cream was applied after suturing on wound site and it was repeated for 6 days (twice in a day), in group III (n  = 10) lidocaine/prilocaine cream was applied topically after suturing and repeated 6 days (twice in a day). At day 7, incisions were excised for evaluating tensile strength and 5-hydroxyproline (5-HP) values. Tensile strength values were lowest in control group and highest in lidocaine/prilocaine treatment group. 5-HP values were also expressed the same results. Both tensile strength and 5-HP values increased significantly in treatment groups in regard to the control (p  < 0.05). It was concluded that lidocaine/prilocaine cream as topical anaesthetic agent had no adverse effect in an incisional wound model, furthermore it may have some beneficial effects on wound healing which remains to be evaluated and it can be used safely in day-to-day emergency practices.

Spontaneous hepatic rupture in pregnancy.

The HELLP-syndrome (haemolysis, elevated liver enzymes, low platelets) is associated with pre-eclampsia and may cause subcapsular liver haematomas. When hepatic rupture occurs the mortality of mother and unborn is high. Rupture remains a surgical emergency with control of bleeding based on trauma principles. We report a case and discuss the diagnosis and management.

A RAT MODEL OF POLYPROPYLENE GRAFT INFECTION CAUSED BY STAPHYLOCOCCUS EPIDERMIDIS

Background:  The aim of this study was to constitute a valid graft infection model with Staphylococcus epidermidis in rats.

The effect of hypothermia on splanchnic flows and lung in a two-hit hemorrhagic shock model.

BACKGROUND To evaluate the effect of hypothermia on bacterial translocation, splanchnic vascular flow, lung tissue weight, and levels of malondialdehyde (MDA) and nitric oxide (NO) in a two-hit model of hemorrhagic shock. METHODS Thirty rats were randomly allocated into three groups of 10 rats each. In the control group (group C), rats were treated without hemorrhage, and normothermia (37 degrees C) was maintained. In the mild hypothermia group (group MH), rats were subjected to volume-controlled hemorrhage (2 mL/100g) and a rectal temperature of 34 degrees C was maintained. In the normothermic group (group NT), rats were treated as in group MH, except for hypothermia. Seventy-two hours after hemorrhagic shock (first insult), Pseudomonas aeuruginosa was administered intratracheally as a second insult. Finally, mesenteric vascular flow patterns were recorded. Bacterial translocation was studied from tissue samples of spleen, liver, and mesenteric lymph nodes. Blood samples were obtained to evaluate the possible presence of bacteria in the bloodstream. Lung tissue weight ratio, MDA, and NO levels in lung tissue were assessed. RESULTS Renal, mesenteric, and portal venous flow rates were found to be lower in groups MH and NT in comparison with group C. Blood flow profiles were lower in group NT than in group MH (P<0.05). Bacterial translocation was not observed in group C, and it was detected more often in group NT than in group MH. Lung weight ratio was found to be higher in group NT compared with groups MH and C. Although it did not reach the level of statistical significance, MDA level in the control group was lower than that in the NT group (P=0.085). CONCLUSION Hypothermia corrected mesenteric blood flow and decreased the occurrence of bacterial translocation in the two-hit model of hemorrhagic shock and tracheal inoculaton of P. aeruginosa.

Mild Hypothermia Improves Survival During Hemorrhagic Shock Without Affecting Bacterial Translocation

Background: Accidental hypothermia in patients with hemorrhagic shock (HS) is associated with increased mortality. However, experimental mild and moderate hypothermia has beneficial effects. The mechanisms for beneficial effects of hypothermia have not been completely understood. Therefore, the aim of this study was to investigate the effect of hypothermia on survival, bacterial translocation (BT), and remote pulmonary injury in a controlled HS model in rats. Methods: HS was achieved by blood withdrawal through femoral vein. Rats in the normothermia group (group I) were maintained at 37°C. Mild hypothermia group (group II) was observed at 32°C that was spontaneously induced by exposure to ambient temperature. Moderate hypothermia of 28°C was actively induced by external cooling in group III for 90 min. Survival and neurological deficit scores (NDS) were recorded at 24th hr. Mesenteric lymph nodes, liver and spleen samples were collected. Myeloperoxidase (MPO) and malondialdehyde (MDA) levels were measured in lung tissue. Results: Blood pressure significantly increased in hypothermia groups. Mild hypothermia significantly increased survival. No difference was found in BT rates in groups. Hypothermia was found to significantly decrease the NDS points in group III, compared to group I. There was no difference in lung tissue MPO levels among groups. Lung tissue MDA levels increased significantly in groups II and III. Conclusions: Mild hypothermia improved blood pressure, survival, and neurological outcome with a possible detrimental effect on pulmonary ROS production during HS in rats. These effects of hypothermia are not associated with BT.

Effect of Carnitine on Cutaneous Wound Healing in Immunosuppressed Rats

BACKGROUND The wound is ischemic in nature. Chronic steroid administration impairs wound healing by changing enzymes in the glycolytic pathway. Carnitine supplementation may help to restore the energy deficiency caused by chronic steroid administration in the wound. The aim of this study was to evaluate the effect of carnitine on impaired wound healing. METHODS The study was conducted in three groups. Surgical intervention was a 4 cm long midline skin incision at the back. In Group A, eight rats received methylprednisolone for 7 d prior to surgical intervention, and it was continued until the end of the experiment. In Group B, 12 rats received methylprednisolone for 7 d prior to surgical intervention. After surgery, methylprednisolone injection was continued and carnitine was supplemented until the end of the experiment. In Group C, eight rats received no medication. The wound of half of the animals in each group was harvested on the seventh day after surgical intervention and the remaining on the 14th d. Tensile strength and hydroxyproline content were measured in all groups. RESULTS There was no significant difference in parameters in any of the groups on day seven. On day 14, all parameters were statistically different between methylprednisolone and control groups (P < 0.05). Values for tensile strength were higher in the methylprednisolone/carnitine group compared with methylprednisolone group (P < 0.05). Carnitine administration had also increased hydroxyproline levels in the methylprednisolone/carnitine group compared with the control group (P < 0.05). CONCLUSIONS Carnitine is shown to increase tensile strength of the wound when supplemented to immunosuppressed rats in which wound healing is impaired by methylprednisolone.