Predictors of Difficult Ultrasound-Guided Transversus Abdominis Plane Blocks

Background Fascial plane blocks are a valuable and important aspect of patient care. However, nerve blocks sometimes present with a technical difficulty that can lead to upsetting the operating room schedule, cause discomfort to the patient, or lead to inadequate block. Potential predictors of this difficulty were evaluated. Methods In a single-blind study, ultrasound image quality was evaluated on a grading metric, and its correlation with several factors that could potentially impact the difficulty of a procedure, including age, BMI, weight, length of surgery, IV fluids, and pre-vs postoperative block, was assessed. Results No correlation was found between any of our anesthetic, patient, or surgical factors, and the resulting image quality. Conclusion The study population was limited compared to our initial goals. We found no correlation between studied variables and image quality, but confounding factors that may affect image quality have not been ruled out.