Mustafa Saçar

Systemic and local antibiotic prophylaxis in the prevention of Staphylococcus epidermidis graft infection

BackgroundThe aim of the study was to investigate the in vivo efficacy of local and systemic antibiotic prophylaxis in the prevention of Staphylococcus (S.) epidermidis graft infection in a rat model and to evaluate the bacterial adherence to frequently used prosthetic graft materials.MethodsGraft infections were established in the subcutaneous tissue of 120 male Wistar rats by implantation of Dacron/ePTFE grafts followed by topical inoculation with 2 × 107 CFUs of clinical isolate of methicillin-resistant S. epidermidis. Each of the graft series included a control group, one contaminated group that did not receive any antibiotic prophylaxis, two contaminated groups that received systemic prophylaxis with teicoplanin or levofloxacin and two contaminated groups that received teicoplanin-soaked or levofloxacin-soaked grafts. The grafts were removed 7 days after implantation and evaluated by quantitative culture.ResultsThere was significant bacterial growth inhibition in the groups given systemic or local prophylaxis (P < 0.05). Methicillin-resistant S. epidermidis had greater affinity to Dacron graft when compared with ePTFE graft in the untreated contaminated groups (P < 0.05).ConclusionThe study demonstrated that the usage of systemic or local prophylaxis and preference of ePTFE graft can be useful in reducing the risk of vascular graft infections caused by staphylococcal strains with high levels of resistance.

Activated protein C attenuates intestinal reperfusion-induced acute lung injury : an experimental study in a rat model

BACKGROUND Activated protein C (APC) is a serine protease with anticoagulant and anti-inflammatory activities. APC has been shown to attenuate local deleterious effects of ischemia/reperfusion (I/R) injury in many organs. We aimed to investigate the effects of APC on lung reperfusion injury induced by superior mesenteric occlusion. METHODS Male Wistar-Albino rats were allocated into 4 groups: (1) sham-operated group, laparotomy without I/R injury (n = 12); (2) sham + APC group, identical to group 1 except for APC treatment (n = 12); (3) intestinal I/R group, 60 minutes of ischemia followed by 3 hours of reperfusion (n = 12); and (4) I/R + APC-treated group, 100 microg/kg injection of APC intravenously, 15 minutes before reperfusion (n = 12). Evans blue dye was injected into half of the rats in all groups. We assessed the degree of pulmonary tissue injury by measuring activities of oxidative and antioxidative enzymes, as well as nitrate (NO(3)(-))/nitrite (NO(2)(-)) levels, biochemically. We evaluated acute lung injury (ALI) by establishing pulmonary neutrophil sequestration and ALI scoring histopathologically. Pulmonary edema was estimated by using Evans blue dye extravasation and wet/dry ratios. The plasma levels of proinflammatory cytokines and D-dimer were measured. RESULTS APC treatment significantly reduced activities of oxidative enzymes and nitrate/nitrite levels in the lung tissues, and plasma levels of proinflammatory cytokines and D-dimer, and also significantly increased activities of antioxidative enzymes (P < .05). Pulmonary neutrophil sequestration and ALI scores were decreased significantly with APC administration (P < .05). In addition, APC treatment significantly alleviated pulmonary edema (P < .05). CONCLUSIONS This study clearly showed that APC treatment significantly attenuated the lung reperfusion injury. Further clinical studies are required to clarify whether APC has a useful role in the reperfusion injury during particular surgeries in which I/R-induced organ injury occurs.

Hyperbaric Oxygen as Adjunctive Therapy in Experimental Mediastinitis

BACKGROUND Mediastinitis is a dreaded complication of cardiac surgical procedures. The purpose of our study was to research the role of hyperbaric oxygen therapy (HBO) in the treatment of experimental mediastinitis and to investigate whether it potentiates the antibiotic effects of linezolid, teicoplanin, and vancomycin. METHODS The study included nine groups; an uncontaminated and a contaminated untreated control groups, and seven contaminated groups that received HBO or systemic antibiotics with linezolid, vancomycin, or teicoplanin, or a combination therapy consisting of one of these antibiotics and HBO. There were six adult male Wistar rats in each group. Contaminated groups were inoculated with 0.5 mL 10(8) CFU/mL methicillin resistant Staphylococcus aureus in the mediastinal and in the sternal layers. The antibiotic treatment continued 7 d. Twelve hours later at the end of the treatment, the rats were sacrificed, a sternotomy was performed for each rat and tissue samples from the upper ends of the sternum were aseptically obtained and evaluated microbiologically. RESULTS There was no difference between the therapeutic efficacy of linezolid, teicoplanin, or vancomycin (P>0.05). When the groups were analyzed separately, treatment with a combination of HBO and antibiotic therapy reduced the bacterial count in comparison with HBO or antibiotic treatment alone (P<0.05). The combination of teicoplanin or vancomycin and HBO, respectively, was not more effective in reducing the bacterial count in comparison with the combination of linezolid and HBO (P>0.05). CONCLUSIONS Linezolid and teicoplanin therapy was found as effective as standard vancomycin therapy for methicillin resistant Staphylococcus aureus (MRSA) mediastinitis. Adjunctive HBO offered additional benefit to the antibiotic treatment of mediastinitis.

Preservation of pleural integrity in patients undergoing coronary artery bypass grafting: effect on postoperative bleeding and respiratory function.

Objective —The purpose of this study was to evaluate the influence of preserved integrity of pleura on postoperative bleeding and respiratory function in patients undergoing coronary artery bypass grafting (CABG). Methods and results — Seventy-two CABG patients who received pedunculated IMA graft without opening the pleura (group of intact pleura, group IP) between July 2002 and September 2004 were matched to 72 CABG patients who received pedunculated IMA graft with opened pleura (group of opened pleura, group OP).To match the patients with IP and unique patients with OP, logistic regression was used to develop a propensity score. The C statistic for this model was 0.79. Patients with IP were matched to unique patients with OP with an identical 5-digit propensity score. If this could not be done, we proceeded to a 4-, 3-, 2-, or 1-digit match. Patients characteristics were well matched. There were no differences in preoperative and peroperative variables between the groups. The incidence of postoperative pleural effusion and thoracentesis were significantly lower in group IP than group OP (pleural effusion in 15.2 versus 30.5%; p = 0.029, thoracentesis in 5.5 versus 18.5%; p = 0.036). Other pulmonary complications such as prolonged ventilation, reintubation, pneumothorax, atelectasis, diaphragmatic paralysis were similar in both groups. Patients with IP had significantly lower blood loss (520 versus 870 ml; p < 0.001) and whole blood unit transfusion (26.3 versus 41.6%, p = 0.036). Also, intensive care unit and hospital stay were similar in both groups. Conclusions — Meticulous internal mammary artery harvesting and preservation of the pleural integrity significantly reduces postoperative bleeding and pleural effusion.

Pyrrolidine Dithiocarbamate Prevents Deleterious Effects of Remote Ischemia/Reperfusion Injury on Healing of Colonic Anastomoses in Rats

BackgroundPyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-κB (NF-κB) activation. It has been shown to attenuate local harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent animal studies, a delaying effect of remote organ I/R injury on the healing of colonic anastomoses has been demonstrated. In this study we investigated whether PDTC prevents harmful systemic effects of superior mesenteric I/R on left colonic anastomosis in rats.MethodsAnastomosis of the left colon was performed in 40 rats randomly allocated into the following four groups: (1) Sham-operated group (group I, n = 10)—simultaneously with colonic anastomosis, the superior mesenteric artery and collateral branches divided from the celiac axis and the inferior mesenteric artery were isolated but not occluded. (2) Sham+PDTC group (group II, n = 10)—identical to sham-operated rats except for the administration of PDTC (100 mg/kg IV bolus) 30 minutes prior to commencing the experimental period. (3) I/R group (group III, n = 10)—60 minutes of intestinal I/R by superior mesenteric artery occlusion. (4) PDTC-treated group (group IV, n = 10)—PDTC 100 mg/kg before and after the I/R. On postoperative day 6, all animals were sacrificed, and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for investigation of anastomotic hydroxyproline (HP) contents, perianastomotic malondialdehyde (MDA) levels, myeloperoxidase activity (MPO), and glutathione (GSH) level.ResultsThere was a statistically significant decrease in anastomotic bursting pressure values, tissue HP content and GSH level, along with an increase in MDA level and MPO activity in group III, when compared to groups I, II, and IV (p < 0.05). However, PDTC treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP content and GSH level, along with a decrease in MDA level and MPO activity in group IV (p < 0.05).ConclusionsThis study showed that PDTC treatment significantly prevented the delaying effect of remote organ I/R injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent for increasing the safety of the anastomosis during particular operations where remote organ I/R injury occurs.

Activated protein C attenuates intestinal mucosal injury after mesenteric ischemia/reperfusion.

BACKGROUND Activated protein C (APC) is a serine protease with anticoagulant and ant-inflammatory activities. APC has been shown to attenuate deleterious effects of ischemia/reperfusion (I/R) injury in many organs. In this study, we aimed to investigate the effects of APC on intestinal mucosal injury induced by superior mesenteric occlusion. MATERIALS AND METHODS Male Wistar-albino rats were allocated into four groups: (1) sham-operated group, laparotomy without I/R injury (n = 12); (2) sham + APC group, identical to Group 1 except for APC treatment (n = 12); (3) I/R group, 60 min of ischemia followed by 3-h of reperfusion (n = 12); and (4) I/R + APC-treated group, 100 mug/kg injection of APC intravenously, 15 min before reperfusion (n = 12). We evaluated the degree of intestinal mucosal injury on a grading scale from 0 to 5, histopathologically, and by measuring activities of oxidative and antioxidative enzymes as well as nitrate/nitrite levels, biochemically. Intestinal edema was estimated by using wet/dry weight ratios. The plasma levels of proinflammatory cytokines and D-dimer were measured. Animal survival was observed up to 1 wk. RESULTS Intestinal mucosal injury scores were significantly decreased with APC administration (P < 0.05). APC treatment significantly reduced activities of oxidative enzymes and nitrate/nitrite levels in the intestinal tissues, and plasma levels of proinflammatory cytokines and D-dimer, and also significantly increased activities of antioxidative enzymes in the intestinal tissues (P < 0.05). Intestinal edema was significantly alleviated with APC treatment (P < 0.05). The survival rate of rats in the APC-treated group were significantly higher than that of the I/R-treated group (P < 0.05). CONCLUSIONS This study clearly showed that APC treatment significantly attenuated intestinal mucosal injury caused by superior mesenteric ischemia/reperfusion. Further clinical studies are required to clarify whether APC has a useful role in reperfusion injury during particular surgeries in which I/R-induced organ injury occurs.

Effect of Diclofenac on Experimental Pleurodesis Induced by Tetracycline in Rabbits

Background and Objective Pleurodesis is a frequently preferred procedure in thoracic surgery, and many factors may affect the process. We aimed to determine whether the administration of systemic diclofenac sodium diminishes the effectiveness of the pleurodesis induced by intrapleural tetracycline in rabbits. Methods Twelve male New Zealand rabbits that received tetracycline 35 mg/kg intrapleurally were allocated into two groups. The first group (diclofenac group, n = 6) received 2 mg/kg diclofenac sodium intramuscularly for 10 days, and the second group (control group, n = 6) received acetaminophen 30 mg/kg orally for 10 days after the pleurodesis procedure. The rabbits were sacrificed after 28 days, and the pleural spaces were assessed grossly for evidence of pleurodesis and microscopically for evidence of fibrosis, inflammation, and collagenization. Results The mean macroscopic pleurodesis score of the diclofenac group was 2.16 ± 0.40 compared with 2.83 ± 0.40 in the control group (p = .027). The mean microscopic pleurodesis score of the diclofenac group was 2. 3 ± 1.03, whereas it was 3.5 ± 0.54 in the control group (p = .045). Conclusion The administration of diclofenac sodium for 10 days following tetracycline pleurodesis reduces the effectiveness of pleurodesis in rabbits.

Activated protein C prevents deleterious effects of remote reperfusion injury caused by intestinal ischemia on wound healing in the left colonic anastomoses: an experimental study in the murine model.

BACKGROUND Activated protein C (APC) is a serine protease with anticoagulant and antiinflammatory activities. The delaying effects of remote reperfusion injury on the wound-healing process in colonic anastomoses have been previously shown. In this study, we aimed to investigate whether APC protects against deleterious systemic effects of intestinal ischemia/reperfusion (I/R) injury on colonic anastomotic wound healing process. METHODS Male Wistar-albino rats were randomly allocated into 4 groups, and a left colonic anastomosis was performed in all animals: (1) sham-operated group, simultaneously with left colonic anastomosis, the superior mesenteric artery and collateral branches were divided from the celiac axis, and the inferior mesenteric artery were isolated but not occluded (group 1, n = 12), (2) sham + APC group, identical to group 1 except for APC treatment (100 microg/kg, intravenously, 15 minutes before construction of the colonic anastomosis), (group 2, n = 12), (3) intestinal I/R group, 60 minutes of superior mesenteric ischemia followed by reperfusion (group 3, n = 12), and (4) APC-treated group, (100 microg/kg, intravenously, 15 minutes before reperfusion) (group 4, n = 12). All animals were sacrificed, and colonic anastomotic bursting pressures were measured in vivo on day 7. Tissue samples were obtained for analysis of hydroxyproline contents, nitrate/nitrite levels, and activities of oxidative and antioxidative enzymes. The plasma levels of proinflammatory cytokines and D-dimer were also measured. RESULTS Intestinal I/R led to significant decreases in colonic anastomotic bursting pressures, tissue hydroxyproline contents, and activities of antioxidative enzymes, along with increases in tissue nitrate/nitrite levels, activities of oxidative enzymes, and plasma levels of proinflammatory cytokines and D-dimer (P < .05). However, APC treatment led to significant increases in colonic anastomotic bursting pressures, tissue hydroxyproline contents, and activities of antioxidative enzymes, along with decreases in tissue nitrate/nitrite levels, activities of oxidative enzymes, and plasma levels of proinflammatory cytokines and D-dimer (P < .05). CONCLUSION This study clearly showed that APC treatment prevented the delaying effects of remote I/R injury on colonic anastomotic wound healing process. Further clinical studies are required to determine whether APC has a useful role in the enhancement of colonic anastomotic wound healing after particular operations in which I/R injury occurs.

Coronary Arterial Revascularization in an Adult with Congenitally Corrected Transposition of Great Arteries and Dextrocardia

Abstract  Objectives:Congenitally corrected transposition of great arteries with dextrocardia is an extremely rare lesion in adulthood. This group of patients does not live long enough for atherosclerotic coronary artery disease processes, because of existing comorbid anomalies. Methods: We report a 47‐year‐old man with isolated congenitally corrected transposition of great arteries, dextrocardia, and athersclerotic coronary artery disease. The patient underwent coronary artery revascularization with cardiopulmonary bypass. The free left internal mammary artery (LIMA) was grafted to the tiny left anterior descending artery (LAD), and the reversed saphenous vein Y graft was anastomosed to the posterior descending and posterolateral branches of the morphologic right coronary artery. Results: The patient recovered uneventfully. He is alive and well 24 months after the surgery. Conclusions: To our knowledge, the present case is the first congenitally corrected transposition of great arteries with dextrocardia treated with grafted coronary artery bypass. Early and full revascularization is very important for the systemic right ventricle exposed to a systemic workload. The vessel pathologies and technical details of this unusual case are discussed in this paper.

Comparison of simultaneous antegrade/vein graft cardioplegia with antegrade cardioplegia for myocardial protection.

Antegrade cardioplegic delivery via the aorta ensures distribution of cardioplegic solution through open arteries, but distribution may not be adequate beyond a stenotic coronary artery. This potential problem can be overcome by direct delivery of cardioplegia via a vein graft. The purpose of this study was to compare simultaneous antegrade/vein graft cardioplegia with antegrade cardioplegia during coronary artery bypass surgery. Twenty patients were divided into 2 groups. In group 1, intermittent antegrade cardioplegia was provided (n=10). In group 2, intermittent antegrade cardioplegia was supplemented by antegrade perfusion of vein grafts after distal anastomoses were completed (n=10). Data on enzyme release and hemodynamics were obtained preoperatively, before the induction of anesthesia, just before cross-clamping, immediately after aortic unclamping, and at 1, 6, 12, 24, and 48 h after unclamping. Enzyme release (creatinine phosphokinase-isoenzyme MB, cardiac troponin I, myoglobin) was similar in both groups (P > .05). Furthermore, no significant difference was noted in the incidence of postoperative low cardiac output syndrome, perioperative myocardial infarction, or ventricular arrhythmia (P > .05). In conclusion, both techniques permitted rapid postoperative recovery of myocardial function. Supplementation of antegrade perfusion of vein grafts with antegrade cold blood cardioplegia offered no advantage to study patients. However, hemostasis of a distal anastomosis may be controlled by this technique.