Greater Occipital Nerve Blockade in Veterans With Post-concussion Headache: Sub-study 1

The acute and subacute sensations that occur on the scalp with injection of different concentrations of bupivacaine for grater occipital nerve blockade will be compared. Each Veteran participant will be randomized to receive three different concentrations, which will be injected one week apart each.

Military Servicemembers are at elevated risk for traumatic brain injury (TBI) and its consequences, including post-traumatic headache (PTH). The most common phenotype of PTH is migraine, for which there are numerous potential treatments, though these have limitations, including poor efficacy, drug-drug interactions, and intolerable side effects. Therefore, the consideration of other methods to manage PTH in Servicemembers and Veterans is warranted. Anesthetic greater occipital nerve (GON) blockade is a simple, inexpensive, and safe procedure that has demonstrable headache pain suppressing effects in a variety of headache disorders. This intervention is frequently done to provide immediate relief, followed by a period of reduced headache burden. The acute burning that occurs during injection and then the numbing over the scalp that occurs shortly after anesthetic GON blockade make controlled investigations against placebo difficult to interpret. In sub-study 1 of this project, different concentrations of bupivacaine (0.0%, 0.01%, 0.05%, 0.1%) will be examined in order to identify a suitable control dose to later compare to the full dose of 0.5%. Acute and subacute sensations from bupivacaine GON blockade will be measured and the lowest concentration that resembles the sensations elicited by full dose (0.5%) will be used in a subsequent efficacy trial (sub-study 2).

Both bupivacaine concentration and order of administration will be unknown except to Research Pharmacy

The maximum intensity of the sensation on the scalp at the time of injection on 0-10 numerical rating scale

Inclusion Criteria: United States Military Veterans within VA Connecticut Healthcare System Chronic post-traumatic headache per ICHD-3 criteria (i.e., headaches are continuing to occur three months after the head injury) At least two headache days per week MRI brain scan completed within the past 3 months if chronic PTH for less than one year, within the past year if chronic PTH for less than 5 years, and within 5 years if chronic PTH for more than 10 years Review of MRI and the medical record does not reveal another source for headache Exclusion Criteria: Skull defect Other contraindication to bupivacaine Allergy or adverse reaction (e.g., rash, cardiac effects) to amide anesthetics, such as lidocaine Instruction from clinician to avoid amide anesthetics, such as lidocaine Pregnant or lack of adequate birth control