Effects of upper limb ischemia-reperfusion on regional oxidative stress during aortic surgery with moderate hypothermia.

INTRODUCTION: This study aims to evaluate the effect of acute, iatrogenic right arm ischemia and reperfusion (I/R) due to right axillary cannulation on regional oxidative stress using tissue perfusion markers such as central venous oxygen saturation, lactate, the difference between central venous and arterial CO2 pressure, near-infrared spectroscopy (NIRS) measurements, and biomarkers like sialic acid, malondialdehyde, advanced oxidative protein products in aortic surgery with moderate hypothermia. METHODS: Adult patients undergoing ascending aorta repair with antegrade cerebral perfusion via the axillary artery participated. Blood samples were collected from the internal jugular vein, right arm cubital vein, and left arm cubital vein, and analysis was performed at intraoperative time points. RESULTS: Right-arm venous oxygen saturation levels are significantly lower than left arm and central venous, as expected in iatrogenic ischemia. Right arm lactate levels are significantly higher. Somatic right arm NIRS values are significantly lower than somatic left arm. There are no significant differences for biomarkers throughout the time points. CONCLUSIONS: We have concluded that well-known markers reflect the results of ischemia-reperfusion more rapidly, and are more valuable than novel biomarkers. NIRS is a promising monitor in terms of providing information about tissue oxygenation. Oxidative stress biomarkers do not change quickly enough to give useful information in a short enough period of time; moreover, their costs are high and laboratory studies take time. Although axillary cannulation is controlled limb ischemia, the local effects of I/R did not completely normalize at the end of the surgery, and this regional I/R did not affect the global body organism.

Effects of intraoperative fluid therapy on intensive care process, morbidity, and mortality after lung transplantation.

Background: This study aims to evaluate the effect of intraoperative fluid therapy on intensive care process and first 90-day morbidity and mortality in patients undergoing lung transplantation. Methods: Between March 2013 and December 2020, a total of 77 patients (64 males, 13 females; mean age: 47.6±13.0 years; range, 19 to 67 years) who underwent lung transplantation were retrospectively analyzed. The patients were divided into two groups according to the amount of fluid given intraoperatively: Group 1 (<15 mL/kg-1/h-1) and Group 2 (>15 mL/kg-1/h-1). Demographic, clinical, intra- and postoperative data of the patients were recorded. Results: Less than 15 mL/kg-1/h-1 f luid w as a dministered t o 75.3% (n=58) of the patients (Group 1) and 24.7% (n=19) were administered more than 15 mL/kg-1/h-1 (Group 2). In t erms of native disease, the rate of diagnosis of chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis was higher in Group 1, and the rate of other diagnoses was higher in Group 2 (p<0.01). The ratio of women in Group 2 was higher (p<0.05), while the body mass index values were significantly lower in this group (p<0.01). The erythrocyte, fresh frozen plasma, platelet, crystalloid and total fluid given in Group 2 were significantly higher (p<0.001). Inotropic/vasopressor agent use rates and extracorporeal membrane oxygenation requirement were significantly higher in Group 2 (p<0.01). Primary graft dysfunction, gastrointestinal complications, and mortality rates were also significantly higher in Group 2 (p<0.05). Conclusion: The increased intraoperative fluid volume in lung transplantation is associated with primary graft dysfunction, gastrointestinal complications, and mortality rates.

Dynamic Thiol-Disulfide Homeostasis as a Marker for Oxidative Stress in Lung Transplant Candidates.

OBJECTIVES: Oxidative stress developing due to oxidant/antioxidant imbalance plays a crucial role in the etiopathogenesis of chronic progressive lung diseases.The condition is typically more severe in lung transplant candidates with end-stage lung disease. Here, we investigated dynamic thiol-disulfide homeostasis as a marker for oxidative stress in lung transplant candidates. MATERIALS AND METHODS: The study included 40 patients with end-stage lung disease with indications for lung transplant (candidate group) and 40 healthy controls. Patient demographic data, laboratory results, and thiol-disulfide homeostasis values were recorded. We categorized patients according to their primary diseases and noted clinical measurements of forced expiratory volume in 1 second, forced vital capacity, 6-minute walk test, systolic pulmonary artery pressure, and lung allocation scores.Thiol-disulfide homeostasis parameters were compared before and after transplant. RESULTS: Demographic characteristics were similar in the candidate and control groups. In the candidate group, native thiol and total thiol levels (antioxidant parameters of thiol-disulfide homeostasis) were significantly lower, whereas disulfide-to-native thiol and disulfide-to-total thiol ratios (oxidant parameters of thiol-disulfide homeostasis) were significantly higher. We observed no significant differences between the disease subgroups in terms of thioldisulfide homeostasis parameters. Moderately significant correlations were shown between the antioxidant markers ofthiol-disulfide homeostasis and the clinical measurements, including the lung allocation scores. Our multiple regression analyses showed that native thiol and total thiol were significant predictive factors to estimate the lung allocation score. During the study period, 6 patients (15%)received lung transplant. There were significant differences in antioxidant parameters ofthiol-disulfide homeostasis in the pre- versus posttransplant periods. CONCLUSIONS: In patients with end-stage lung disease, the dynamic thiol-disulfide homeostasis status is altered in favor of oxidants. Thus, thiol-disulfide homeostasis parameters can be used to detect oxidative stress and estimate lung allocation scores in these patients. Lung transplant may have positive effects on oxidative stress.

COVID-19 After Vaccination in Lung Transplant Recipients: Real-Life Data.

OBJECTIVES: The effectiveness of COVID-19 vaccines in lung transplant recipients is unclear. We retrospectively analyzed lung transplant recipients vaccinated with an inactivated virus vaccine (CoronaVac) and the mRNA vaccine BNT162b2 used against the SARS-CoV-2 virus in Turkey and shared their effects on COVID-19. MATERIALS AND METHODS: Demographic data of lung transplant recipients followed up for >3 months were collected, and vaccination dates and status against the SARS-CoV-2 virus were recorded. Recipients who received at least 3 doses of CoronaVac or 2 doses of BNT162b2, or 1 dose of CoronaVac plus 2 doses of BNT162b2, or 2 doses of CoronaVac plus 1 dose of BNT162b2 were considered fully vaccinated; those who were vaccinated less than this number were considered partially vaccinated. Patients with positive SARS-CoV-2 reverse transcription-polymerase chain reaction tests from respiratory tract samples were accepted as positive for COVID-19. Recipients were classified by number and type of vaccine, and groups were compared for infection, need for intensive care, and death as a result of COVID-19. RESULTS: Of the 53 lung transplant recipients, 51 were vaccinated (7 partially vaccinated, 44 fully vaccinated) and 2 were not vaccinated. Of fully vaccinated recipients, 13/44 received the inactivated vaccine, 5/44 received the mRNA vaccine, and 26/44 had a combination of the 2 vaccines. During the follow-up period, 13 patients (2/2 not vaccinated, 2/7 [28.5%] partially vaccinated, 9/44 [20.5%] fully vaccinated) were diagnosed with COVID-19. There was no significant difference in protection against infection between the inactivated, the mRNA, and combined vaccine groups. There was no significant association in cycle threshold values that determine the infection load and COVID-19 severity between transplant recipients who died and those who did not. CONCLUSIONS: In lung transplant recipients, 3 doses of inactivated vaccine, 2 doses of mRNA vaccine, or the combined heterologous vaccine provided similar protection. Prevention of exposure is one of the most crucial steps.

COVID-19 in a Lung Transplant Patient: Rapid Progressive Chronic Lung Allograft Dysfunction.

The pandemic of SARS-CoV-2, known as COVID-19, has continued to show its effect all over the world. The clinical course of the disease in solid-organ transplant recipients is a matter of concern. Lung transplant recipients also demonstrate special features because the graft encounters the COVID-19 pathogen directly as a result of inhalation, and the lungs are the most important organs affected by the disease. We shared the development process of acute rejection followed by rapid progression of chronic lung allograft dysfunction after COVID-19 in a recipient who was followed-up in the fifth year after lung transplant.