Opioid Sparing Effect of an ISP Nerve Block on Post-Op Pain Control in Posterior Cervical Spine Surgery

The purpose of this research study is to evaluate the opioid-sparing effect of the use of an Inter-semispinalis plane (ISP) block after posterior cervical spine surgery.

Posterior cervical fusion (PCF) is a painful procedure that often requires the use of high doses of opioids to minimize postoperative pain. Uncontrolled pain can result in a delay in recovery and discharge. Additionally, high doses of opioids carry the risk of opioid dependence, and other side effects, include nausea, vomiting, sedation, and, in rare cases, respiratory depression. For all of the above reasons, reducing the use of opioids is of utmost importance.

Nerve blocks are one alternative to opioid use. The ISP block is a procedure described in 2017; it is a relatively simple procedure that entails injecting local anesthetic between two muscles in the back of the neck, bilaterally, to block the nerves that run in this plane. It is done under ultrasound guidance and, although a limited number of studies have shown promise, more data on its safety and efficacy are needed. The addition of Dexamethasone to local anesthetics, in nerve blocks, resulted in significant prolongation of the analgesia.

• Inter-semispinalis Plane Block (Procedure), also known as ISP nerve block: A nerve block targeting the dorsal rami of the cervical spinal nerves can help alleviate postoperative incisional pain.
• Opioids (Drug), also known as Pharmacologic pain management: Routine Pain Management

Primary outcomes

• Lower opioid use [48 hours post Post-Anaesthesia Care Unit (PACU) arrival time]: Comparison of the reduction in Morphine Milligram Equivalent (MME) dose of opioids consumed between the control group versus the nerve block group.

Secondary outcomes

• Lower opioid use. [MME use will be recorded from the patient's Anesthesia induction time until the patient's PACU arrival time. This will be the intra-operative period, which may last several hours, but not expected to exceed eight hours.]: MME from anesthesia induction time until PACU arrival time.
• Lower opioid use [24 hours after PACU arrival time]: MME for the 24 hours after PACU arrival time
• Pain Scores [48 hours after PACU arrival time]: Using a Numeric Rating Scale (NRS), pain scores will be obtained at specified times and then compared between the two groups. Participants will be asked to rate their pain on a scale from 0 - 10, where zero represents 'no pain at all' and 10 represents 'the worst pain ever possible'.
• Length of hospital stay [The patient's EMR will record the date and time of admission, as well as, the date and time of discharge. This will be quantified by the REDCap software being used for this study, and is not expected to exceed four days.]: The length of hospital stay will be compared between the two groups.

Sex: All, ages: 18 Years to 75 Years, accepts healthy volunteers

Inclusion Criteria:

* Having Posterior Cervical Spine Surgery from C2 - C7, which may extend to the upper thoracic vertebrae, inclusive to T3.
* Capacity to provide informed consent

Exclusion Criteria:

* Fusion and decompression due to trauma
* Emergent procedures
* Patient is on a medication-assisted treatment, e.g., buprenorphine, naltrexone or methadone.
* There is an infection near or in the area of neck where the block will be placed.
* The patient is having a complicated surgery or a revision surgery
* Female patient with a positive pregnancy test on the day of surgery (hospital standard-of-care).
* Patient has Diabetes
* Patients who have had a prior adverse reaction to bupivacaine or dexamethasone
* Patients with Glucose-6-phosphate dehydrogenase deficiency or congenital or idiopathic methemoglobinemia

• Eman Nada, MBBCH, Principal investigator, Stony Brook University Hospital