Perioperative Methadone Compared to Placebo in Elderly Hip Fracture Patients

All opioids (short-acting and long-acting) will be converted into daily morphine milligram equivalent doses. The amount of opioids used by the patient within the last 24 hours will be registered daily. A minimum amount of 0 mg and a maximum amount of 150 mg can be recorded.

The opioid consumption will be registered as a mean daily consumption of both long-acting opioids and rescue medication prescribed in the medication chart and reported by the patient. Different types of opioids will be converted into the daily morphine milligram equivalent dose. Minimum score will be 0 mg and the maximum will be 150 mg.

Patients will be asked to assess pain intensity daily in the hip both at rest and when mobilized. Pain intensity will be evaluated using the verbal rating scale consisting of five choices - 1 (No pain), 2 (Slight pain), 3 (Moderate pain), 4 (Severe pain), and 5 (Unbearable pain).

This will be registered in hours and minutes. The minimum is 0 hours and 0 minutes and the maximum is 72 hours and 0 minutes.

The cumulated ambulation score describes the patient's independence with regard to three activities. The first getting in and out of bed, the second ability to transition from sit-to-stand-to-sit from a chair, and the third is walking ability. Each of these activities is assessed on a three-point scale from 0-2 (0 = Not able to, despite human assistance and verbal cueing, 1 = Able to, with human assistance and/or verbal cueing from one or more persons, 2 = Able to safely, without human assistance or verbal cueing. A CAS score will range from zero (worst) to six (best) and will be measure daily.

Postoperative nausea or vomiting (PONV) will be registered binomial as "yes" or "no" once daily

The number of days from ward admission until discharge. Patients moved to another department are still considered hospitalized. The minimum is 0 days and the maximum is 14 days.

Administration of an antidote will be registered binomial as "yes" or "no". Indications for the use of an antidote include a respiratory frequency of <10/min with peripheral oxygenation of <94% despite 4 liters of oxygen/minute, clinical signs of opioid overdose e.g. disproportionate drowsiness, or if the orthopaedic resident deems it necessary.

Patients will be monitored using the confusion assessment method for signs of delirium. The method is binomial so that 0 means no signs of delirium and 1 means a patient is delirious.

Occurrence of constipation during admission will be registered binomial as "yes" or "no". A patient with no bowel movements for ≥2 days is considered constipated.

Patients will be asked to assess pain intensity daily in the hip both at rest and when mobilized. Pain intensity will be evaluated using the verbal rating scale consisting of five choices - 1 (No pain), 2 (Slight pain), 3 (Moderate pain), 4 (Severe pain), and 5 (Unbearable pain).

The questionnaire comprises of five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each dimension has 5 levels: no problems, slight problems, moderate problems, severe problems and extreme problems. The patient is asked to indicate his/her health state by ticking the box next to the most appropriate statement in each of the five dimensions. This decision results in a 1-digit number that expresses the level selected for that dimension. The digits for the five dimensions can be combined into a 5-digit number that describes the patient's health state.

New mobility score assesses gait; inside the home, outside the home and whilst shopping. A score of 0-3 points is given for each of these three functions, resulting in a total score between 0-9 points.

The persistent presence of potential adverse reactions will be registered. This includes disproportional dizziness, vertigo, nausea, vomiting, constipation, and drowsiness.