Ketamine for Acute Migraine in the Emergency Department
Condition: Headache
MeSH terms: Migraine Disorders; Emergencies; Headache
Study type: Interventional

Summary: 
      This research study will be a prospective, randomized, double-blind, placebo-controlled
      trial. Because ketamine has yet to be directly studied as treatment for acute migraine
      headache in the emergency department, the research team is initially interested if ketamine
      can reduce pain scores in headache patients and reduce the incidence of recurrence while
      exhibiting an adequate safety profile. By using a placebo-controlled study design, the
      research team can adequately investigate the effectiveness of the medication in a subgroup
      previously not well studied.
    

Detailed description: 
      The investigators propose enrollment of patients upon or shortly after presentation to the
      emergency department for treatment with ketamine or placebo. 30 minutes after study drug is
      administered, patients will have the option to request rescue medication which will be
      ordered by the treating physician according to standard emergency department protocol. Pain
      scores will be documented using the Numerical rating scale (NRS-11), 4-Point Pain Intensity
      Categorical Scale, and 4-Point Functional Disability Scale at 0 minutes, 30 minutes, and 60
      minutes post treatment. Follow-up telephone calls will be made 72-120 hours after treatment
      to assess the incidence of recurrence of head pain and patient satisfaction with the
      treatment.

      Subjects eligible for this study must present to the emergency department with a chief
      complaint of primary headache that is determined non-emergent by the treating physician.

      Upon block randomization, each subject will receive an intravenous dose of 0.2 mg/kg, with a
      maximum dose of 30mg, of ketamine or an equivalent volume of saline. After 30 minutes
      patients will be asked if they need rescue medication, and the treating physician will
      administer rescue treatment, if requested.

      The research hypotheses include:

        1. The proportion of patients achieving significant pain reduction at 30 minutes will be
           higher in the ketamine treatment group compared to the placebo group.

        2. The proportion of patients experiencing pain response, defined as <50% reduction in the
           visual analog score compare to the baseline and a reduction of the 4-Point Pain
           Intensity Categorical Scale to a 1 or 0, will be higher for patients receiving ketamine
           compared to those receiving the placebo.

        3. Patients treated with ketamine for headache will experience lower recurrence rates
           within 24 hours

        4. Ketamine will demonstrate an adequate safety profile.

      The last two questions will be exploratory and not included in the power analysis.

      It is expected that ketamine will demonstrate a satisfactory safety profile with limited side
      effects. The proportion of patients attaining pain response is expected to be higher in the
      ketamine treatment group compared to placebo. It is also expected that patients treated with
      ketamine alone will be less likely to experience a recurring headache within 72 hours of
      treatment than those treated with placebo and rescue medication.

      The primary outcome will be achievement of pain response at 30 minutes after ketamine dose.
      Achievement of pain response will be defined as reduction in baseline pain score by at least
      50% on the NRS scale. Secondary outcomes will include attainment of pain-free state, patient
      headache relief, recurrence of headache, recovery of functional disability, and need for
      rescue medication.
    

Intervention name(s): Ketamine; Normal Saline
Intervention type(s): Drug; Drug
Intervention description(s): Patients in this arm will receive 0.2mg/kg ketamine intravenously, pain scores will be collected after 30 minutes. At that time rescue medication will also be offered. Pain scores will continued to be recorded until 60 minutes have passed since drug administration.; Patients will receive normal saline intravenously, pain scores will be collected after 30 minutes. At that time rescue medication will also be offered. Pain scores will continued to be recorded until 60 minutes have passed since drug administration.
Intervention MeSH terms: Ketamine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Treatment
Keywords: Ketamine; Migraine; Headache; Emergency Department