Comparison Between Oxycodone and Pregabalin as Preemptive Analgesia

The research will be conducted between March 2021 and June 2023. All patients scheduled electively for one of four surgeries (Laparoscopic Cholecystectomy, Submucosal resection, Breast lumpectomy, and median laparotomy) at that period of time at An-Najah National University hospital will be included in the research sample, unless not meeting with the criteria put.

Primary objectives are:

To evaluate the effectiveness of preemptive analgesia on postoperative pain relief and shorter hospital stay for adults undergoing surgical procedures, according to the type of surgery and the type of drug.

To compare the effect of a single oral preemptive dose of Pregabalin versus Oxycodone on postoperative pain relief, in terms of pain intensity as assessed by pain numeric rating scale (NRS)

* After signing the informed consent, each participant will undergo standard care for any surgical patient (general examination, vital signs recording, history taking, and cannula insertion). Then, a nurse will teach him\\her how to use the NRS for pain scores.
* Patients will be randomly allocated by computer-generated list to Group A (oxycodone 20 mg orally), Group B (pregabalin 150 mg orally), or Group C (multivitamins pill orally).
* The medication will be given 30 minutes before operation by an anesthesiology resident who is not aware of the study design in a closed envelope with a code similar to the file code of the participant and he will make sure that the participant ingests the pill with a sip of water and get rid of the envelope immediately.
* The participant then will be transferred to the preparation room before surgery, baseline scores will be recorded for the following parameter: pain scale (NRS) during rest and movement, Modified Ramsay Sedation Score (MRSS), and vital signs.
* Patient then will be transferred to the operation room, and induction of anaesthesia will begin.

The anaesthetic protocol will be standardized.

* The anaesthetists will record the duration of surgery as the time between induction of anaesthesia and arrival to Post-Anesthetic Care Unit (PACU). Arrival to PACU will be recorded as 0 times.
* The participant will be sent to the ward after collecting 8 points or greater or return to baseline on Post-Anesthesia Recovery Score (PARS). Time in PACU will be reported.
* A postoperative patient evaluation will be performed by an anaesthetist who will be unaware of the study design.
* Postoperative pain treatment will be with patient-controlled IV morphine 2.5 mg bolus (rescue analgesia). Nausea will be treated with ondansetron.
* Morphine consumption, pain intensity at rest and during mobilization, nausea and vomiting, sedation, dizziness, and consumption of ondansetron will be recorded at 0, 1, 4, and 8 h after operation.
* On discharge, time and date of discharge and satisfaction of analgesia score will be recorded.

Eligibility Criteria:
Inclusion Criteria:

1. Age \> 18-year-old.
2. Patients undergoing elective surgeries under general anesthesia.
3. American Society of Anesthesiology grade 1 or 2.
4. BMI 18-35 Kg/m2
5. Reliable participant (he/she can give history by him/herself)

Exclusion Criteria:

1. Current Pregnancy or breastfeeding.
2. Chronic use of analgesia (use of any analgesic drug for most days in the last three months).
3. Current use of analgesia (within last 24 hours).
4. Allergy to any medication used in the study.
5. Smoking or Nargila use within last 24 hour before surgery and until discharge.
6. History of psychiatric medication or disease.
7. Discharge from hospital within 6 hours after surgery.
8. Participants transferred from the ward to ICU or other wards.
9. Known case of liver or kidney impairment.
10. History of alcohol use or illicit drug.
11. Any complication during surgery leads to changes in protocol of the study.