The effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on local tissue reaction and inflammation in rabbit carotid artery anastomosis.

OBJECTIVES: In addition to the hemostatic properties of hemostatic agents, the investigation of their immunogenic properties, their local effects on application area has been the subject of many experimental studies. There are limited data on the inflammatory effects of Bovine serum albumin-glutaraldehyde and Polyethylene glycol polymer. Therefore, we investigated the effects of these agents on tissue reactions and inflammation in rabbit carotid artery anastomosis in our experimental study. METHODS: Twenty-one New Zealand male rabbits were randomly divided into three groups. The right carotid artery anastomosis was performed on the control group after transection. Hemostatic agents were applied locally to other two groups separately after transection and anastomosis. At the end of 28 days, the type of inflammation, inflammatory cell infiltration, degree of inflammation, and amount of residual adhesives were examined and compared statistically. RESULTS: Cell infiltrations associated with inflammation on the anastomosis site (eosinophils, epithelioid/giant cells, lymphocytes, and plasma cells) and inflammation grade in the groups of hemostatic agents were significantly lower compared to the control group (p < .05). There was no difference between the hemostatic agents. While mild inflammation (61.9%) was dominant in the groups of hemostatic agents, moderate inflammation (85.7%) was more common in the control group. No severe inflammation was observed in any of the three groups. Residual sealant grade between hemostatic agents did not differ significantly. CONCLUSIONS: When inflammation and tissue reactions of the 4th week were evaluated, it was determined that both hemostatic agents did not cause severe inflammation. However, comparative results at multiple time intervals are needed due to the dynamic process of inflammation.

Direct kidney injury or lower extremity ischemia induced indirect kidney injury: Which one is more harmful for kidneys?

OBJECTIVES: The aim of this study was to investigate and compare the severity of kidney damage following lower limb ischemia-reperfusion and direct kidney ischemia-reperfusion. METHODS: Thirty Sprague Dawley male rats were randomly divided into three groups; lower extremity ischemia-reperfusion group (Group 2), renal ischemia-reperfusion group (Group 3) and control (anesthesia and median laparotomy only) (Group 1). In group 3, 1-h ischemia was performed on the kidney and in group 2, 1-h ischemia was performed on the left lower extremity. This procedure was followed by reperfusion for 24 h. Renal tissues were removed after the reperfusion period and the groups were evaluated for glutathioneperoxidase activity, malondialdehyde and GSH levels, and furthermore, their histolopathological scores were calculated. RESULTS: Renal malondialdehyde levels were significantly higher in Group 2 and Group 3 than they were in the Control group. There was no significant difference in renal malondialdehyde levels between Group 2 and Group 3. Kidney glutathione (GSH) levels were statistically lower in Group 2 and Group 3 than in the Control group. No statistically significant difference was found between Group 2 and Group 3 regarding their GSH levels. In histological evaluation, there was no statistically significant difference between Group 2 and Group 3 in terms of kidney damage score. CONCLUSIONS: This study has identified that lower extremity ischemia induces remote kidney damage with similar features to kidney injury, occurring after direct kidney ischemia-reperfusion.

Which Distant Organ is Most Affected by Lower Extremity Ischemia-Reperfusion?

BACKGROUND: It has been experimentally shown that reperfusion injury occurs in many remote organs after ischemia-reperfusion (I/R) of the lower extremity. However, which distant organ is affected more after I/R of the lower extremity has not been investigated. In this study, we investigate which remote organ is predominantly affected after lower extremity I/R. METHODS: Twenty male Sprague-Dawley rats were randomly divided into 2 groups: sham (group 1) and lower extremity I/R (group 2). In group 2, 1 hr of ischemia of the left lower extremity was followed by 24 hr of reperfusion of the limb. After reperfusion, the lung, liver, kidney, heart, and small intestine tissues were harvested in both groups. RESULTS: In the I/R group, the malondialdehyde levels were significantly higher in the heart and small intestine tissues than those in other tissues (P < 0.05). In addition, in the I/R group, the glutathione and glutathione peroxidase activities were also higher in the heart tissues than those in other tissues (P < 0.05). However, these results were not significant because the malondialdehyde, glutathione, and glutathione peroxidase levels of the heart tissues in the control group were higher than those of the other tissues. Therefore, no statistically significant difference was found between the tissues in terms of the histological damage score we created and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cell numbers. CONCLUSIONS: There was no difference in the severity of reperfusion injury between the tissues we examined after lower extremity I/R. This suggests that every distal organ should be carefully monitored after lower extremity I/R.

Dynamic alterations in cerebral, celiac and renal flows resulting from ascending aorta, subclavian artery and femoral artery cannulations of extracorporeal devices.

INTRODUCTION: The aim of this study was to assess the relationships among cardiac output, extracorporeal blood flow, cannulation site, right (RCa) and left carotid (LCa), celiac (Ca) and renal artery (Ra) flows during extracorporeal circulation. METHODS: A mock circulatory circuit was assembled, based on a compliant anatomical aortic model. The ascending aorta, right subclavian and femoral artery cannulations were created and flow was provided by a centrifugal pump (Cp); cardiac output was provided by a roller pump (Rp). Five volume flow rates were tested. The Rp was set at 4 L/min with no Cp flow (R4-C0) and the basic volume flow rates of the vessels were measured. The flow of the Cp was increased while the Rp flow was decreased for other measurements; R3-C1, R2-C2, R1-C3 and R0-C4. Measurements were repeated for all cannulation sites. RESULTS: The RCa flow rate at R4-C0 was higher compared to the R3-C1, R2-C2, R1-C3 and R0-C4 RCa flows with subclavian cannulation. The RCa flow decreased as the Cp flow increased (p<0.05). The RCa flow with ascending aortic and femoral cannulation was higher compared to subclavian cannulation. Higher flows were obtained with subclavian cannulation in the LCa compared to the others (p<0.05). R4-C0 Ca and Ra flows were higher compared to other Ca and Ra flows with femoral cannulation. Ca and Ra flows decreased as Cp flow increased. Flows of the Ca and Ra with ascending and subclavian cannulations were not lower compared to the R4-C0 flow (p<0.05). CONCLUSION: This study shows that prolonged extracorporeal circulation may develop flow decrease and ischemia in cerebral and abdominal organs with both subclavian and femoral cannulations.

Should we change the cannulation site for right subclavian artery cannulation? An experimental study with a newly designed cannula.

BACKGROUND:: In this experimental study, we primarily aimed to show the hemodynamic effects and superiority of this newly designed cannula for perfusion compared to standard subclavian cannulation. The new cannula (Figure 1) allows bidirectional axial flow and it directly fits in the brachiocephalic trunk (innominate artery). METHODS:: We used a cardiopulmonary bypass roller pump, reservoir, 3/8- 1/2- 1/4-inch Y-connectors and tubing set. Lines were set as seen in Figures 2, 3, 4 and 5. The anatomy of the aorta (ascending, arch, branches, descending) was mimicked, using tubing sets with different sizes and the connectors yielding similar angles and configurations. In this experimental vascular system, systemic vascular resistance was created with partial clamping of the common tubing set. The cannulation sites were created in the subclavian artery and the innominate artery. Perfusion was established with the same pump rate and the same occlusion pressures (systemic vascular resistance). The pressure readings were obtained in the right carotid artery, the left carotid artery and the left subclavian artery. RESULTS:: These experimental models of vasculature allowed us to measure pressures in the carotid system for different cannulation set-ups, using both our newly designed double-outflow cannula, which was introduced via the innominate artery, and the standard arterial cannula, which was introduced via the subclavian artery. Higher pressure recordings were obtained in the carotid system with the new cannula introduced through innominate artery. CONCLUSION:: Higher cerebral perfusion readings were obtained with our newly designed bidirectional cannula introduced via the innominate artery compared to standard cannulation through the right subclavian artery.

An experimental model of aortic surgery and the effect of Iloprost on lung injury.

OBJECTIVES: Ischemia/reperfusion (I/R) damage of the lung is a frequently encountered complication following aortic surgery. The aim of the present study is to investigate the histopathological effects of Iloprost on pulmonary damage developed after I/R. DESIGN: Twenty-four Sprague-Dawley rats were randomly divided into 3 groups. In the control group, aortas were not clamped. In the I/R group, aortas were occluded, and after 1 h of ischemia, clamps were removed. After 2 h of reperfusion period, lungs of the rats were extracted. In the I/R + Iloprost group after 1 h of ischemia, Iloprost infusion was initiated, and maintained for the duration of 2 h reperfusion period. For histopathological scoring, density of polymorphonuclear leucocytes, congestion, interstitial edema, and bleeding were semiquantitatively evaluated, and histopathological changes were scored. RESULTS: In the I/R group, multifocal-marked histopathological changes in 5 (62.5%), and multifocal-moderate histopathological changes in 3 (37.5%) rats were detected. In the I/R + Iloprost group, multifocal-moderate histopathological changes in 4 (50%), and multifocal-mild changes in 4 (50%) rats were detected. CONCLUSIONS: In the experimental rat model, administration of Iloprost has been shown to have preventive effects for pulmonary damage occurring after I/R generated by infrarenal aortic occlusion.

The effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on neointimal hyperplasia in rabbit carotid artery anastomosis.

OBJECTIVE: Since the systemic drugs have been used to reduce the hyperplasic response in the tunica intima, the periadventitial local drug applications to the vascular wall have gained more popularity. In this study, we investigated the effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on neointimal hyperplasia in rabbit carotid artery anastomosis to explore the effects of these two different agents. METHODS: 21 New Zealand male rabbits were randomly divided into three groups. The carotid artery transection and anastomosis was performed onthe control group. The bovine serum albumin-glutaraldehyde and the polyethylene glycol polymer were applied locally on the other two groups seperatley after transection and anastomosis of the carotid arteries. At the end of 28-day follow-up, the histological and the immunohistochemical results related to neointimal hyperplasia were compared. RESULTS: The glue residues were detected in the BSA-glutaraldehyde group, but in the PEG polymer group there was no glue residue. The intima thickness and the intima/media thickness ratio in the control group was significantly higher (p<0.05) than the other groups. These values did not differ significantly between the BSA-glutaraldehyde group and the PEG polymer group (p>0.05). The lumen diameter and the area in the control group were significantly higher (p < 0.05) than the BSA-glutaraldehyde group. These values between the control group and the PEG polymer group did not differ significantly (p>0.05). aSMA-positive staining score in the Control group was found to be significantly lower (p < 0.05) than the BSA-glutaraldehyde and PEG polymer group and the VEGF-positive staining score in the control group was found to be significantly higher (p < 0.05) than the BSA-glutaraldehyde and the PEG polymer group. CONCLUSIONS: Although the both agents have positive results on neointimal hyperplasia, it would be favorable to use polyethylene glycol polymer, since it does not seem to affect the lumen area and the lumen diameter of the vessel.

Surgical Management of Left Sinus of Valsalva Aneurysm Presenting with Exertional Chest Pain.

Left sinus of Valsalva aneurysm (SVA) is a very infrequent clinical entity. Valsalva aneurysms are often asymptomatic in right and non-coronary sinuses and the diagnosis is often incidental. A left SVA which presents with exertional chest pain due to compression of left coronary system arteries is extremely rare. In this case, we present a successful surgical repair of left SVA without aortic regurgitation or myocardial infarction in a 59-year-old male patient.

How important is the damage to the liver after lower limb ischemia-reperfusion? An experimental study in a rat model.

BACKGROUND: The aim of this study was to compare the effect of lower extremity ischemia reperfusion on the liver and the effect of ischemiareperfusion on the liver itself in a rat model. METHODS: Thirty Sprague-Dawley male rats were randomly divided into three groups including 10 in each group: sham (Group 1), lower limb ischemia-reperfusion (Group 2), and liver ischemia-reperfusion (Group 3). In Group 2, one hour of left lower limb ischemia was performed. In Group 3, one hour of ischemia in the liver was performed, followed by 24 hours of reperfusion. After reperfusion, the liver tissues were removed, and the groups were evaluated biochemically and histologically. RESULTS: The liver malondialdehyde levels were significantly higher in Groups 2 and 3 than in the sham group (p<0.001). In Group 2, the malondialdehyde levels were significantly higher than in Group 3 (p=0.019). The glutathione levels in the liver were significantly lower in Groups 2 and 3 than in the sham group (p<0.001). However, the glutathione levels were significantly higher in Group 2 than in Group 3 (p=0.005). In the histological evaluation, although the liver damage score was higher in Group 3 than in Group 2 (p=0.015), there was no significant difference between the two groups in TUNEL(+) cell number (p>0.05). CONCLUSION: Reperfusion injury in the liver after lower limb ischemiareperfusion is as important as ischemia-reperfusion injury which is specifically induced in the liver. This should be taken into account, particularly in reperfusion surgeries following vascular trauma or in cases of leg tourniquets to stop bleeding after lower limb vascular trauma.

Comparison of Femoral and Axillary Artery Cannulation in Acute Type A Aortic Dissection Surgery.

INTRODUCTION: One of the most important points of the acute type A aortic dissection surgery is how to perform cannulation regarding cerebral protection concerns and the conditions of arterial structures as a pathophysiological consequence of the disease. OBJECTIVE: In this study, femoral and axillary cannulation methods were compared in acute type A aortic dissection operations. METHODS: The study retrospectively evaluated 52 patients who underwent emergency surgery for acute type A aortic dissection. Patients without malperfusion according to Penn Aa classification were chosen for preoperative standardization of the study groups. The femoral arterial cannulation group was group 1 (n=22) and the axillary arterial cannulation group was group 2 (n=30). The groups were compared in terms of perioperative and postoperative results. RESULTS: There was no statistically significant difference in terms of preoperative data. In terms of postoperative parameters, especially early mortality and new-onset cerebrovascular event, there was no statistically significant difference. Mortality rates in group 1 and group 2 were 13.6% (n=3) and 10% (n=3), respectively (P=0.685). Postoperative new-onset cerebral events ratio was found in 5 (22.7%) in the femoral cannulation group and 6 (20%) in the axillary cannulation group (P=0.812). CONCLUSION: Both femoral and axillary arterial cannulation methods can be safely performed in patients with acute type A aortic dissection, provided that cerebral protection strategies should be considered in the first place. The method to be performed may vary depending on the patient's current medical condition or the surgeon's preference.

"Overtime Hours Effect" on Emergency Surgery of Acute Type A Aortic Dissection.

OBJECTIVE: Treatment of acute diseases of the aorta is still associated with high mortality and morbidity. It is believed that interventions for these diseases on overtime hours (night shifts or weekend shifts) may increase mortality. In this study, we investigated the effect of performing acute type A aortic dissection surgery on overtime hours in terms of postoperative outcomes. METHODS: 206 patients who underwent emergency surgery for acute type A aortic dissection were retrospectively evaluated. Two groups were constituted: patients operated on daytime working hours (n=61), and patients operated on overtime hours (n=145), respectively. RESULTS: Chronic obstructive pulmonary disease and repeat surgery were higher in group 1. There was no statistically significant difference between the two groups in terms of operative and postoperative results. Mortality rates and postoperative neurological complications in group 1 were 9.8% and 13.1%, respectively. In group 2, these rates were 13.8% and 12.4%, respectively (P=0.485 - P=0.890). Multivariate analysis identified that cross-clamp time, amount of postoperative drainage, preoperative loss of consciousness and postoperative neurological complications are the independent predictors of mortality. CONCLUSIONS: As the surgical experience of the clinics improves, treatment of acute type A aortic dissections can be successfully performed both overtime and daytime working hours.

Inflammation, Atrial Fibrillation and Cardiac Surgery: Current Medical and Invasive Approaches for the Treatment of Atrial Fibrillation.

Atrial fibrillation (AF) is a cardiac dysrhythmia commonly seen in clinical practice especially after cardiac surgery. It is associated with increased morbidity and mortality for the patients. The pathogenesis of AF is not exactly understood yet, but there is growing data about the relationship between AF and inflammation. Cardiac surgery itself is a big source for inflammation. It causes major surgical trauma, ischemia/reperfusion injury, hypothermia, low arterial pressure, and the equipment of cardiopulmonary bypass makes a large foreign surface thus it activates inflammatory response. There is a large number of data about the treatment options of AF and there are also strategies, which are related to reduction of inflammatory activation during cardiopulmonary bypass. In order to review the relationship between cardiac surgery, inflammation, AF and treatment strategies in patients with AF, we conducted a search through Pubmed for articles in English using the keywords: "atrial fibrillation, cardiac surgery, inflammation, medical therapy, surgical therapy, ablation therapy" from January 2012 to present. We also searched separately for each alternative treatment modality on Pubmed. To identify further articles, we also looked into related citations in review articles and commentaries. We searched thoroughly the guidelines published by the European Society of Cardiology (2016), and the American Heart Association/ American College of Cardiology/ Heart Rhythm Surgery (2014). Many studies concluded that inflammation contributes in the occurrence of AF. Inflammatory markers, such as CRP, interleukins and complements have high sensitivity and specificity for prediction of AF whether the patient having cardiac surgery or not. Betablockers, diltiazem and amiodarone are the most commonly used drugs for rate control in AF following surgery. Although there are some new therapeutic approaches to reduce postoperative inflammatory activation, such as the use of vitamins, fatty acids, statins, or technical improvements to cardiopulmonary bypass unit like miniaturized bypass circuits, heparin coating of the circuits, leukocyte filters, or various surgical approaches like off-pump coronary bypass surgery, we still need more effective strategies to reduce both postoperative inflammation and postoperative AF risk after cardiac surgery. Today we use more advanced invasive and surgical treatment strategies for AF although we need far more advanced technics to reduce perioperative inflammatory activation, which actually causes AF.

The effects of sildenafil and n-acetylcysteine on ischemia and reperfusion injury in gastrocnemius muscle and femoral artery endothelium.

PURPOSE: We aimed to examine the effects of sildenafil and n-acetylcystein on ischemia/reperfusion injury in femoral artery endothelium and gastrocnemius muscle. BASIC METHODS: 32 rats of Sprague-Dawley breed were randomly divided into four groups (n=8). Median laparotomy was performed, then a 120-minute ischemia was created by microvascular clamping of infrarenal aorta, followed by the release of clamping. In sildenafil group, 1 mg/kg of sildenafil infusion and in the n-acetylcystein group, 100 mg/kg of n-acetylcystein infusion was administered after release of clamps. Blood samples and tissue samples of femoral artery and gastrocnemius muscle were extracted for a histopathological evaluation. PRINCIPAL FINDINGS: Serum levels of malondialdehyde in ischemia/reperfusion group (6.16±0.79) were higher compared to the control group (4.69±0.33), whereas a significant decrease was detected in sildenafil (5.17±0.50) and n-acetylcystein (4.96±0.49) groups. Femoral artery tissue sections of the control group, mean tumor necrosis factor alpha and hypoxy-induced factor-1 alpha immunoreactivity were found to be negative. In the ischemia/reperfusion group, mean tumor necrosis factor α immunoreactivity was intense and mean hypoxy-induced factor-1 alpha immunoreactivity was 51-75%. In the ischemia/reperfusion+Sildenafil and ischemia/reperfusion+NAS groups, mean tumor necrosis factor α immunoreactivity was slight and mean hypoxy-induced factor-1 alpha immunoreactivity was 26-50%. CONCLUSIONS: In conclusion, sildenafil and n-acetylcystein may reduce femoral artery endothelium and gastrocnemius muscle injury following lower extremity ischemia/reperfusion.