Pericapsular Nerve Group Block Versus Intrathecal Morphine for Analgesia After Total Hip Arthroplasty

Total amount of oxycodone delivered by the intravenous PCA pump, calculated as the sum of all delivered PCA boluses and reported in milligrams. Lower values indicate lower postoperative opioid requirement.

Total number of patient-initiated analgesia requests (button presses) recorded by the intravenous patient-controlled analgesia (PCA) pump. This measure includes all demand attempts, regardless of whether a bolus was delivered. Reported as count.

Patient-reported pain intensity at rest assessed using the 11-point Numerical Rating Scale (NRS), where 0 = no pain and 10 = worst imaginable pain. Higher scores indicate worse pain. Pain score is recorded at each scheduled assessment time point.

Patient-reported dynamic pain intensity during passive straight leg raise of the operated limb (knee extended and hip flexed to 45°), assessed using the 11-point Numerical Rating Scale (NRS), where 0 = no pain and 10 = worst imaginable pain. Higher scores indicate worse pain. Pain score is recorded at each scheduled assessment time point.

Patient-reported satisfaction with postoperative analgesia assessed using a 5-point Likert satisfaction scale:

• = definitely dissatisfied,
• = dissatisfied,
• = neither satisfied nor dissatisfied (neutral),
• = satisfied,
• = definitely satisfied. Higher scores indicate greater satisfaction.

Assessment via a Visual Analogue Scale (VAS), where "0" indicates no nausea and "10" indicates the most severe nausea

Assessment via a Visual Analogue Scale (VAS), where "0" indicates no pruritus and "10" indicates the worst possible itching

Duration from hospital admission to hospital discharge, reported in days.

Sedation/agitation is assessed using the Richmond Agitation-Sedation Scale (RASS), ranging from -5 to +4, where:

• 5 = unarousable,
• 4 = deep sedation,
• 3 = moderate sedation,
• 2 = light sedation,
• 1 = drowsy, 0 = alert and calm,

• 1 = restless,
• 2 = agitated,
• 3 = very agitated,
• 4 = combative. Higher scores indicate greater agitation; lower scores indicate deeper sedation. For postoperative recovery, scores closer to 0 are considered more favorable, while scores further from 0 indicate a less favorable state.

Motor blockade is assessed using the Bromage motor blockade scale from Grade 0 to Grade 3, where:

Grade 0 = no motor blockade (full movement at knee and ankle joints), Grade 1 = partial block (limited/simple knee movement, full foot movement), Grade 2 = almost complete block (no knee movement, preserved foot movement), Grade 3 = complete block (no movement of lower limbs, including knees and feet).

Higher grades indicate greater motor blockade (worse motor function). Lower grades indicate less motor blockade (better motor function recovery).

Evaluation of the spinal anesthesia level based on thermal sensation (using an antiseptic spray)

Total dose of ondansetron and/or other antiemetics administered.

Estimated blood loss during surgery, reported in milliliters (mL).

Time from skin incision to skin closure, reported in minutes.

Number of participants who required at least one vasopressor dose during surgery, reported as count.

Heart rate measured by bedside monitoring and reported in beats per minute (bpm).

Peripheral oxygen saturation measured by pulse oximetry and reported as percent (%).

Non-invasive diastolic blood pressure measured with an automated cuff and reported in mmHg.

Mean arterial pressure reported in mmHg at each assessment time point (device-reported value or calculated from SBP and DBP, per site standard).

Time interval from administration of spinal anesthesia to first mobilization, defined as first upright positioning and/or ambulation, reported in hours.

Number of participants with at least one predefined anesthesia-related complication, including accidental vascular puncture, local anesthetic systemic toxicity (LAST), and respiratory failure. Reported as count.

Number of participants with at least one predefined hospitalization-related complication, including requirement for blood product transfusion, pneumonia, cardiovascular events, and surgical site infection (SSI). Reported as count.