The current study is designed to measure and evaluate the pharmacokinetic profiling of acetaminophen in the young obese patient population.

This will be a descriptive study carried out by study staff from the anesthesiology department. The patient population will include obese patients scheduled for robot-assisted or laparoscopic bariatric surgery. There will be no change in our usual anesthetic care for these patients. Volume of distribution and elimination half-life of acetaminophen in serum samples are the primary measurements of the study. If detected, a significant reduction in opioid requirements may lead to improved patient satisfaction and decreased opiate side effects.

Inclusion Criteria:

• Patients older than 12, but younger than 21 years of age undergoing robotic assisted or laparoscopic bariatric surgery
• American Society of Anesthesiologists Physical Status Classification System (ASA) I, II or III
• Parent/guardian willing and able to give consent
• Patient willing to give assent, or consent
• Patients that are otherwise healthy at the discretion of the study staff
• Patients with BMI >95th percentile

Exclusion Criteria:

• Patients with severe right heart failure or severe asthma
• Patients with deficient hepatic function that can affect drug metabolism
• Systemic steroid use within the last 3 months
• Patients who have taken acetaminophen containing medications within 24 hours of surgery date
• Patients younger than 12, but older than 21 years of age undergoing robotic assisted or laparoscopic bariatric surgery
• Patients having other procedures in addition to robotic assisted or laparoscopic bariatric surgery
• American Society of Anesthesiologists Physical Status Classification System (ASA) IV and above
• Females testing positive for pregnancy
• Parent/guardian not willing and able to give assent, or consent
• Patient not willing to give assent, or consent
• Patients with BMI < 95th percentile

The study population will consist of 30 patients presenting to the OR for robotic assisted or laparoscopic bariatric surgery.

12 hours