ANATOMICAL VARIATIONS OF THE BRACHIAL PLEXUS AND THEIR PHARMACOLOGICAL IMPLICATIONS IN REGIONAL ANESTHESIA: A CLINICAL OBSERVATIONAL STUDY
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Keywords
Anatomy, Pharmacology, Brachial Plexus, Regional Anesthesia, Ultrasonography
Abstract
Background: Understanding anatomical variations of the brachial plexus is essential for effective administration of regional anesthesia. Variations in nerve branching patterns can influence the spread and efficacy of local anesthetic drugs, potentially leading to failed blocks or complications. Pharmacological considerations such as dose adjustment and choice of anesthetic agents must be tailored to the anatomical findings.
Methodology: A total of 100 adult patients undergoing upper limb surgeries requiring brachial plexus block were included in this observational study. Pre-procedural ultrasonography was performed to assess anatomical variations in nerve branching, fascicular arrangement, and surrounding structures. Standardized doses of bupivacaine and lidocaine were administered, and block success rate, onset time, duration of analgesia, and complications were recorded. Data were analyzed using descriptive statistics and chi-square test for associations between anatomical variations and pharmacological outcomes.
Results: Out of 100 patients, 28% demonstrated anatomical variations of the brachial plexus, including atypical branching and aberrant fascicular patterns. These variations were significantly associated with delayed onset of anesthesia (p < 0.05) and increased requirement of supplemental doses. Patients with typical anatomy showed higher block success rates (95%) compared to those with variations (78%). No major complications were reported, though minor vascular punctures occurred in 6% of cases.
Conclusion: Anatomical variations of the brachial plexus significantly affect the pharmacological efficacy of regional anesthesia. Incorporating ultrasonographic evaluation prior to block administration enhances drug delivery precision, reduces complications, and optimizes clinical outcomes. A combined anatomical and pharmacological approach is crucial for safe and effective anesthesia practice.
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Dr. Halima Sadia
Assistant Professor, Department of Pharmacology Bacha Khan Medical College, Mardan, Pakistan.
Dr. Amna Halima
Assistant Professor Anatomy, Bacha Khan Medical College, Mardan, Pakistan
Zarak Iqbal
Final Year MBBS, Abbottabad International Medical College, Abbottabad, Pakistan
Afaf Ayaz Khan
Final Year MBBS, Abbottabad International Medical College, Abbottabad, Pakistan
Dr. Rysaeva Safia
Demonstrator, Biochemistry Department, Abbottabad International Medical College, Abbottabad, Pakistan
Syeda Aliza Fatima
Final Year MBBS, Abbottabad International Medical College, Abbottabad, Pakistan