Postoperative Opioid Use and Pain Scores in Patients Undergoing Transforaminal Lumbar Interbody Fusion

Phase 4

Terminated

Brief Summary: The purpose of this project is to study the effects of preoperative followed by scheduled intravenous acetaminophen on pain control for 24 hours postoperatively after minimally invasive 1 or 2 level transforaminal lumbar interbody fusion.

Detailed Description: The purpose of this project is to study the effects of preoperative followed by scheduled intravenous acetaminophen on pain control for 24 hours postoperatively after minimally invasive 1 or 2 level transforaminal lumbar interbody fusion. The advantages of intravenous acetaminophen are well known in the literature and its opioid-sparing effects have been documented in multiple surgical studies.

Multimodal regimens are now being advocated in the literature to decrease opioid use (8, 23). This is especially significant in spine surgery patients who often have chronic pain requiring long-term use of these habit-forming drugs as well as in patients who may not be able to tolerate opiods due to health status.

To our knowledge there are no studies done in the U.S. on the opioid sparing and pain reducing effects of intravenous acetaminophen on patients undergoing elective minimally invasive 1 or 2 level transforaminal lumbar interbody fusion. Investigating intravenous acetaminophen, particularly its pain reducing and opioid sparing effects, may give surgeons another medication for use in a multimodal approach to pain.

Recruitment & Eligibility

Inclusion Criteria

Age > 18 years old
Being scheduled to have elective primary minimally invasive 1 or 2 level transforaminal lumbar laminectomy interbody fusion
ASA I, II, or III
Informed consent form signed

Exclusion Criteria

Anyone weighing less than 50kg (as this would require a dosing change).
Hypersensitivity or contraindication to intravenous acetaminophen or opioids
Allergy to Methocarbamol; morphine sulfate, sevoflourane, or fentanyl
Impairment of liver function-- defined as the inability to receive intravenous acetaminophen without dose adjustment as determined by the investigator; or history of chronic liver disease defined as history of hepatitis of any kind as recorded in the patient's chart
Mental retardation recorded as a diagnosis in the patient's chart
History of chronic pain (defined as currently receiving treatment from a specialist for pain)
History of pain recalcitrant to intravenous morphine
Impaired kidney function (defined as creatinine > 1.5)
Anyone who is not a candidate for general anesthesia or any other portion of the investigator's standard of

Arm && Interventions

Group	Intervention	Description
PlaceboComparator	Placebo comparator	Placebo Comparator 0.9% NaCl 100 mL over will be administered intravenously over a period of 15 minutes, 15 minutes (+/- 10 minutes) prior to the anticipated time of incision and every 6 hours (+/- 30 minutes) after the initial dose for 24 hours
acetaminophen	Acetaminophen	1g intravenous acetaminophen over a period of 15 minutes, 15 minutes (+/- 10 minutes) prior to the anticipated time of incision and every 6 hours (+/- 30 minutes) after the initial dose for 24 hours; maximum dose of 4 grams in 24 hours

Primary Outcome Measures

Name	Time	Method
VAS	Q4 x 24 hours averaged	The Visual Analogue Scale (VAS) and Verbal Rating Scale (VRS) will be measured at 4 hour intervals for a 24-hr period - measures of pain intensity in clinical and research settings. 0-10 Numeric pain intensity scale. 0 is no pain, 5 is moderate pain, and 10 is worst possible pain

Secondary Outcome Measures

Name	Time	Method
Vital Signs	4-hour intervals (+/- 30 minutes) for 24-hrs averaged	Routine postoperative vital signs will be collected at 4-hour intervals (+/- 30 minutes) postoperatively respiratory rate, oxygen saturation, mean arterial pressure, and heart rate. Any reports of headache, dizziness, nausea, vomiting, pruritis, agitation, constipation, insomnia, bradycardia (Heart rate below 60 beats per minute), hypotension (MAP less than 30% of baseline), or urinary retention will be recorded throughout the study and will be treated appropriately as they occur, and the treatment medication will be stopped if determined to be a causative factor.
Level of 100% Sedation	4-hr intervals for a 24-hr period averaged	Sedation will be measured on a scale of 1 to 5 at 4-hour intervals as follows: 1-completely awake; 2-awake but drowsy; 3 asleep, but responds to verbal commands; 4-asleep but responds to tactile stimuli; and 5-asleep and not responding to any stimuli.