Anesthesia and Analgesia

The goal of this clinical trial is to learn if a new local anesthesia technique can control pain as well as the standard spinal anesthesia for adults having hip endoprosthesis surgery. The main questions it aims to answer are: * Is the new local anesthesia technique as effective as standard spinal anesthesia in managing pain during the first two days after surgery? * Does the new technique allow participants to move their leg sooner after the operation? Researchers will compare the new local anesthesia technique (numbing medicine injected directly around the hip joint) to standard spinal anesthesia (a numbing injection in the back) to see if the new technique works just as well for pain control while possibly causing fewer side effects like nausea. Participants who join this study will be randomly placed into one of two groups. One group will receive the standard spinal anesthesia before their surgery. The other group will receive the new local anesthesia technique before their surgery. After the operation, researchers will track the amount of extra pain medicine each participant uses and will check their ability to move their hip, knee, and foot.

Modern anesthesiology, in search of alternatives to opioid-based pain management, is turning to low-opioid and non-opioid protocols. Replacing opioids with non-opioid analgesics, co-analgesics, and regional and local anesthesia techniques allows avoiding the adverse effects of opioids while maintaining satisfactory analgesia. This is of particular importance in bariatric surgery, where reducing the incidence of respiratory depression, sedation, opioid hyperalgesia, and postoperative nausea and vomiting is a priority. Standard non-opioid anesthesia (OFA) includes ketamine, lidocaine, and dexmedetomidine infusions, while regional techniques additionally reduce the need for analgesics. Despite the widespread use of these methods, there is no clear data on the superiority of any of them in bariatric procedures.

Rationale: While total knee replacements (TKA) are one of the most commonly performed surgical procedures in the United States, this procedure can also be very painful. Postoperative mobilization and rehabilitation is vital to a patient's recovery, but inadequate pain control can impede patients' progress. Diaphragmatic breathing is an additional non-pharmacological and non-invasive tool with no adverse effects that could aid in recovery. This will serve as a pilot study for a possible larger controlled trials.