The Effectiveness of IV/PO Acetaminophen in the Perioperative Period in Reducing Opiate Use After Lumbar Spine Fusion

Simple explanation and rationale:

Recovery after spine surgery is usually accompanied by severe pain which has traditionally been managed with opioids. It is common practice to supplement opioid treatment with different classes of analgesics which work through alternative pain pathways and receptors in order to achieve an additive or synergistic effect while reducing the amount of opioids necessary for pain control.

Acetaminophen can be a beneficial supplemental analgesic to opioids for postoperative pain relief.

Intervention:

Patients will be randomized to either the treatment with IV acetaminophen (A), PO acetaminophen (B), or hydromorphone control group (C).

Objective/Purpose:

Primary objective is to determine the impact of administering a supplemental non-opioid analgesic drug such as IV or PO acetaminophen on total opioid dose administered over the postoperative period.

Secondary objectives include investigating the impact of IV/PO acetaminophen on the level of postoperative pain, patient satisfaction, and side effects secondary to opioids such as nausea, vomiting, pruritus, sedation, respiratory depression, ileus, and urinary retention, and PACU (postoperative care unit) discharge time.

Study population:

126 patients will be enrolled in the study (42 for group A, 42 for group B, and 42 for control group C).

Follow-up and Endpoints / Outcomes:

Postoperative assessments will be done at 0, 30, and 60 minutes, 6 hours, 12 hours and 24 hours after surgery. Patients will be evaluated for pain (using a numeric rating scale), total opioid consumption, and for opioid side effects including drowsiness (using the Ramsey sedation scale and the Aldrete score at the time of arrival to and discharge from recovery room), respiratory depression, nausea, vomiting, and pruritus. Patient satisfaction will also be assessed using a numeric rating scale.

Simple explanation and rationale:

Recovery after spine surgery, especially spinal fusion surgery, is usually accompanied by severe pain which has traditionally been managed with opioids. While opioids have been proven effective, they are associated with undesirable side effects including nausea, vomiting, pruritus, sedation, respiratory depression, ileus, and urinary retention leading to increased time required in recovery and a decrease in patient satisfaction. For this reason, it is common practice to supplement opioid treatment with different classes of analgesics which work through alternative pain pathways and receptors in order to achieve an additive or synergistic effect while reducing the amount of opioids necessary for pain control.

Acetaminophen is a centrally-acting cyclooxygenase inhibitor nonsteroidal anti-inflammatory medication that has minimal, if any, gastrointestinal and platelet-inhibiting side effects, and is better tolerated by patients than other cyclooxygenase inhibitors. This medication can be a beneficial supplemental analgesic to opioids for postoperative pain relief. Previously conducted studies demonstrate a rationale for the use of intravenous/PO acetaminophen in a multimodal analgesic regimen to reduce postoperative analgesia.

Intervention:

Patients will be randomized to either the treatment with IV acetaminophen (A), PO acetaminophen (B), or hydromorphone control group (C). Patients who are randomized to group A will receive 1 g of IV acetaminophen during the wound closure and every 4 to 6 hours postoperatively for a total of 4 g in 24 hours. Patients who are randomized to group B will receive 1 g of PO acetaminophen before surgery and every 4 to 6 hours postoperatively for a total of 4 g in 24 hours. Patients who are randomized to control group C will not receive acetaminophen. Post-operatively, patients in both groups will also receive IV hydromorphone PCA (patient-controlled analgesia) only for 24 hours for pain.

Objective/Purpose:

Primary objective is to determine the impact of administering a supplemental non-opioid analgesic drug such as IV or PO acetaminophen on total opioid dose administered over the postoperative period.

Secondary objectives include investigating the impact of IV/PO acetaminophen on the level of postoperative pain, patient satisfaction, and side effects secondary to opioids such as nausea, vomiting, pruritus, sedation, respiratory depression, ileus, and urinary retention, and PACU discharge time.

Study population:

126 patients will be enrolled in the study (42 for group A, 42 for group B, and 42 for control group C).

Follow-up and Endpoints / Outcomes:

Postoperative assessments will be done at 0, 30, and 60 minutes, 6 hours, 12 hours and 24 hours after surgery. Patients will be evaluated for pain (using a numeric rating scale), total opioid consumption, and for opioid side effects including drowsiness (using the Ramsey sedation scale and the Aldrete score at the time of arrival to and discharge from recovery room), respiratory depression, nausea, vomiting, and pruritus. Patient satisfaction will also be assessed using a numeric rating scale.

Statistics:

All sample size calculations with reference to:

* Specific Aim 1 reduction of opioid intake by at least 25% between the Control (Group C) and Intervention Groups A and B, and
* Specific Aim 2 improvement of Pain Score by at least 25% between the Control (Group C) and the Intervention Groups A and B,

Eligibility Criteria:
Inclusion Criteria:

* ASA (American Society of Anesthesiologists) I-III patients scheduled for elective one or two level minimally invasive lumbar fusions

Exclusion Criteria:

* Patients requiring surgery for neoplastic processes
* Allergy to acetaminophen
* Liver dysfunction and elevated Liver Function Tests (LFTs)
* Alcohol or drug dependency
* Mental retardation
* Less than 50 kg of weight
* regnant women
* Patients requiring long-acting opioid pain management (including fentanyl patch, oxycontin, etc) for over 3 weeks immediately prior to surgery