Effects of Anesthesia Technique on Endothelial Function

The Effects of General Anesthesia and Infraclavicular Block Applications on Oxidative Stress and Endothelial Dysfunction in Upper Extremity Surgeries

The aim of this study was to compare the effects of two different anesthesia methods, general anesthesia and infraclavicular block, on oxidative stress and endothelial dysfunction in upper extremity forearm operations.This prospective study aims to determine the ideal anesthesia method for patients undergoing upper extremity forearm surgeries under tourniquet by comparing general anesthesia and infraclavicular block applications in terms of oxidative stress and ED related to ischemia-reperfusion injury.

Pneumatic tourniquets are commonly used in orthopedic extremity surgeries to reduce surgical trauma and blood loss. When the tourniquet is released, it leads to the release of more free oxygen radicals than under physiological conditions, resulting in ischemia-reperfusion injury, oxidative stress, and endothelial dysfunction (ED).

Endothelial dysfunction is characterized by the imbalance between vasoactive substances such as nitric oxide (NO) and endothelin, which regulate vascular tone by exerting vasodilatory and vasoconstrictive effects.During ischemia, xanthine oxidase (XO) derived from xanthine dehydrogenase is the main source of free oxygen radicals (FOR), including superoxide anion (O2-), hydrogen peroxide (H2O2), and hydroxyl anion (OH-). Superoxide anion reacts with NO to produce peroxynitrite (ONOO-), a reactive oxygen derivative. Free radicals affect unsaturated fatty acids in membranes, leading to the production of malondialdehyde (MDA), which exerts cytotoxic effects on endothelial cells. Increased production of FOR due to oxidative stress and dysfunction of antioxidant mechanisms result in protein carbonylation. Protein carbonyl groups (PC) serve as indicators of severe oxidative damage and loss of protein function

Inclusion Criteria:

• Scheduled for upper extremity surgery using a pneumatic tourniquet
• American Society of Anesthesiologists (ASA) physical status classification I

Exclusion Criteria:

• Under 18 or over 65 years of age
• Hypertension
• Diabetes mellitus
• Malignancy
• Cardiovascular disease history (congestive heart failure, myocardial infarction, venous thrombosis)
• Cerebrovascular disease history
• Liver/kidney dysfunction
• Pregnant or breastfeeding women
• History of substance and tobacco use
• History of extremity ischemia