Predictors of brain injury after experimental hypothermic circulatory arrest:an experimental study using a chronic porcine model

Abstract There is a lack of reliable methods of evaluation of brain ischemic injury in patients undergoing cardiac surgery. The present study was, therefore, planned to evaluate whether serum S100β protein (I), brain cortical microdialysis (II), intracranial pressure (III) and electroencephalography (EEG) (IV) are predictive of postoperative death and brain ischemic injury in an experimental surviving porcine model of hypothermic circulatory arrest (HCA). One hundred and twenty eight (128) female, juvenile (8 to 10 weeks of age) pigs of native stock, weighing 21.0 to 38.2 kg, underwent cardio-pulmonary bypass prior to, and following, a 75-minute period of HCA at a brain temperature of 18°C. During the operation, hemodynamic, electrocardiograph and temperature monitoring was performed continuously. Furthermore, metabolic parameters were monitored at baseline, end of cooling, at intervals of two, four and eight hours after HCA and before extubation. Electroencephalographic recording was performed in all animals, serum S100β protein measurement in 18 animals, cortical microdialysis in 109 animals, and intracranial pressure monitoring in 58 animals. After the operation, assessment of behavior was made on a daily basis until death or elective sacrifice on the seventh postoperative day. All four studies showed that these parameters were predictive of postoperative outcome. Animals with severe histopathological injury had higher serum S100β protein levels at every time interval after HCA. Analysis of cortical brain microdialysis showed that the lactate/glucose ratio was significantly lower and the brain glucose concentration significantly higher among survivors during the early postoperative hours. Intracranial pressure increased significantly after 75 minutes of HCA, and this was associated with a significantly increased risk of postoperative death and brain infarction. A slower recovery of EEG burst percentage after HCA was significantly associated with the development of severe cerebral cortex, brain stem and cerebellum ischemic injury. In conclusion, serum S100β protein proved to be a reliable marker of brain ischemic injury as assessed on histopathological examination. Cerebral microdialysis is a useful method of cerebral monitoring during experimental HCA. Low brain glucose concentrations and high brain lactate/ glucose ratios after HCA are strong predictors of postoperative death. Increased intracranial pressure severely affected the postoperative outcome and may be a potential target for treatment. EEG burst percentage as a sum effect of anesthetic agent and ischemic brain damage is a useful tool for early prediction of severe brain damage after HCA. Among these monitoring methods, brain cortical microdialysis seems to be the most powerful one in predicting brain injury after experimental hypothermic circulatory arrest

Factors associated with delayed venous ulcer healing after endovenous intervention for superficial venous insufficiency

Abstract Objective: This retrospective trial analyzed the effect of predetermined variables on venous ulcer healing after endovenous ablation of insufficient veins. Methods: A total of 259 patients presenting 273 venous leg ulcers (VLUs) at Oulu University Hospital vascular outpatient clinic between January 2010 and December 2020 were included in the study. In addition to compression therapy, all patients received endovenous ablation (endothermal ablation and/or foam sclerotherapy) to promote venous healing. The hazard ratio (HR) for an ulcer to heal was analyzed in univariate analysis of predetermined factors, including age, sex, recurrent venous ulcer, presence of great saphenous vein or small saphenous vein reflux, persistent superficial vein reflux after ablation, recanalization in treated segments, ulcer age, body mass index >35 kg/m², history of deep vein thrombosis, history of erysipelas, ability to move, smoking, hypertension, atrial fibrillation, coronary artery disease, diabetes mellitus, and cardiac insufficiency. Logistic regression was used in a multivariate analysis to identify independent risk factors for ulcer healing. Results: In the univariate analysis, healing was negatively associated with persistent superficial vein reflux after ablation (HR, 0.117; 95% confidence interval [CI], 0.088–0.354), recanalization in treated segments (HR, 0.161; 95% CI, 0.060–0.433), nonambulatory patient (HR, 0.322; 95% CI, 0.130–0.800), history of deep vein thrombosis (HR, 0.518; 95% CI, 0.294–0.910), and presence of small saphenous vein reflux (HR, 0.565; 95% CI, 0.384–0.830). Independent risk factors included persistent superficial vein reflux after ablation (HR, 0.123; 95% CI, 0.0051–0.295). All the patients in the persistent superficial vein reflux group had their VLUs eventually healed after further endovenous treatment. Conclusions: When treating patients with VLUs, persistent superficial vein reflux after ablation was negatively associated with ulcer healing. After additional endovenous ablative treatment, ulcers with persistent reflux eventually healed

A study protocol for comparing the treatment of varicose tributaries either concomitantly with or separately from endovenous laser ablation of the incompetent saphenous trunk (the FinnTrunk Study):a multicenter parallel-group randomized controlled study

Abstract Background: Opinions on the treatment of varicose tributaries in relation to saphenous ablation in varicose disease vary. Moreover, the possible role of the tributaries regarding the recurrence of varicose disease remains unclear. The aim of the FinnTrunk study is to compare two different treatment strategies for varicose disease in a randomized setting. In group one, the initial treatment will entail endovenous laser ablation (EVLA) of the incompetent saphenous trunk without tributary treatment. In group two, the varicose tributaries will be treated with ultrasound-guided foam sclerotherapy (UGFS) concomitantly with truncal ablation. The primary outcome measure is the need for additional procedures during the follow-up. The secondary outcome measures are the cost of treatment and recurrence of varicose disease. Methods: Consecutive patients with symptomatic varicose disease (CEAP clinical class C₂–C₃) will be screened for the study. Patients who fulfil the study criteria and give their informed consent will be scheduled for the procedure and randomized to either study group. Patients will be followed-up at 3 months, 1 year, 3 years, and 5 years. The post-procedure pain score based on a numeric rating scale (NRS) and also the use of analgesics, as well as possible procedure-related complications will be recorded at 3 months. Patient-reported outcome measures (PROMs) will be recorded at 1 year. Data pertaining to the additional treatment of varicose tributaries, the Aberdeen Varicose Vein Questionnaire (AVVQ), the Venous Clinical Severity Score (VCSS), and the health-related quality of life (EQ-5D-5L) will be collected at each follow-up visit. A duplex ultrasound (DUS) examination will be performed at each visit, and data on varicose tributaries and the need for additional treatment will be recorded. Trial registration: Registered on ClinicalTrials.gov, ID NCT04774939