Please select the eligibility criteria that correspond to the clinical trial below.
Title: The Median Effective Dose (ED50) of Paracetamol and Morphine for Postoperative Patients: A Study of Interaction.
Brief Summary: The aim of our study is to define the median effective analgesic doses (ED50) of paracetamol, morphine, and their combination and determination the nature of their interaction administered IV for postoperative pain after moderate painful surgery using up-and-down and isobolographic methods.


Options:
A: Inclusion Criteria:

* Provide written Informed Consent prior to participation in the Study
* Is scheduled to undergo abdominal laparoscopic surgery under general anesthesia (laparoscopic bariatric procedures, including gastric bypass or gastric banding, laparoscopic exploratory procedures in which no visceral dissection is performed, and laparoscopic procedures with minimal visceral dissection, such as laparoscopic sterilization,are excluded)
* If Subject is a female of childbearing potential, have a negative pregnancy test within 21 days of surgery
* Be at least 18, but not more than 80 years of age
* Have a Body Mass Index (BMI) ≥ 19 and ≤ 40 lb/in2
* Have an American Society of Anesthesiologist (ASA) risk class of I, II, or III
* Have the ability to read and understand the Study procedures and the use of the pain scales and have the ability to communicate meaningfully with the Study Investigator and staff
* Be free of other physical, mental, or medical conditions which, in the opinion of the Investigator, makes Study participation inadvisable

Exclusion Criteria:

* Used opioids or tramadol daily for greater than 7 days prior to Study Medication administration (Subjects who, in the Investigator's opinion have or are developing opioid tolerance are to be excluded)
* Has been treated with Chapparal, Comfrey, Germander, Gin Bu Huan, Kava, Pennyroyal, Skullcap, St. John's Wort, or Valerian within 14 days prior to surgery
* Has significant medical disease(s), laboratory abnormalities or condition(s) that in the Investigator's judgment could compromise the Subject's welfare, ability to communicate with the Study staff, complete Study activities, or would otherwise contraindicate Study participation
* Has known hypersensitivity to opioids, acetaminophen, or the inactive ingredients (excipients) of the Study Medication
* Has known or suspected history of alcohol or drug abuse or dependence within the previous 2 years
* Has impaired liver function, e.g., aspartate aminotransferase (AST)/Alanine transaminase (ALT)/bilirubin greater than or equal to 3.0 times the upper limit of normal, active hepatic disease, evidence of clinically significant liver disease, or other condition (e.g., alcoholism, cirrhosis, or hepatitis) that may suggest the potential for an increased susceptibility to hepatic toxicity with Study Medication exposure
* Has been treated with monoamine oxidase inhibitors (MAOIs) within 7 days prior to surgery
* Has participated in another clinical Study (investigational or marketed product) within 30 days of surgery

Post Operative Exclusion Criteria

The Subject must not meet any of the following criteria prior to randomization to Study Medication:

* Had any other surgery than the planned laparoscopic surgery or had intra operative or post operative complications which in the view of the Investigator would make Study participation inadvisable
* Has taken non steroidal anti-inflammatory drugs (NSAIDs), steroids or MAOIs during the day after surgery. Exceptions: The use of low-dose aspirin, e.g, 81 mg/day, for cardioprophylaxis, and limited use of topical or inhaled steroids are acceptable.
* Had any neuraxial (spinal or epidural) opioid injected perioperatively
* Had a local anesthetic injection (including into surgical wound at closure) or continuous infusion by any route
* Had an epidural, regional, or percutaneous (intrawound) catheter with continuous local anesthetic infusion used for postoperative analgesic management
* Had a fever (greater than 38.6 ºC or 101.5 ºF) requiring treatment

Post Operative Day 1 Randomization Criterion On the morning of the first post operative day (POD1), the Subject must have a categorical pain intensity score at rest of moderate or severe and a score ≥ 40 mm and ≤ 70 mm at rest on a 100 mm Visual Analogue Scale (VAS)
B: Inclusion Criteria:

1. ASA physical status І or ІІ
2. Moderately painful surgery patients
3. postoperative pain more than 3 on a numerical pain score (NPS) -

Exclusion Criteria:

1. contraindication to the use of paracetamol and morphine
2. Pregnancy
3. age younger than 18 yr
4. patient weight less 65kg
5. intra-operative regional anesthesia,
6. intra-operative administration of analgesics other than fentanyl,
7. postoperative pain less than 3 on a numerical pain score (NPS)
C: Inclusion Criteria:

* lower abdominal surgery

Exclusion Criteria:

* body weight more than 150% of their ideal body weight
* history of significant cardiac, pulmonary, renal, hepatic or hematological disease; chronic drug or alcohol abuse; hypersensitivity to any of the studied drugs; bronchial asthma; gastritis or peptic ulcer; and pregnancy
* patients who received any analgesic drug a day before surgery
D: Inclusion Criteria:

* American Society of Anesthesiologist (ASA) physical status I and II children undergoing elective lower abdominal surgery

Exclusion Criteria:

* increased intracranial pressure hemorrhagic diathesis infection at the puncture site Those with a known history of allergy to the study drugs

Answer: B