The Effects of Low Dose Ketamine on Cardiovascular Function

Study Overview
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Brief Summary
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Low dose ketamine is used for pain management and for the treatment of anxiety and depression. Prior studies on low dose ketamine have noted short-term (minutes to hours) increases or decreases in blood pressure. Blood pressure that is too high or too low can be problematic if untreated. It is unknown exactly how low dose ketamine affects blood pressure. In fact, no prior studies have measured sympathetic nervous system activity after low dose ketamine has been given to an adult. Because sympathetic nervous system activity has a large influence on blood pressure, we need to know how exactly low dose ketamine affects these body systems. Therefore, in this research we will study how low dose ketamine affects sympathetic nervous system activity and cardiovascular function. The results from this research will inform doctors about how low dose ketamine affects the sympathetic nervous system, heart, and blood vessels.

Official Title
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The Effects of Low Dose Ketamine on Cardiovascular Function

Conditions
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Healthy

Intervention / Treatment
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* Drug: Ketamine
* Drug: Saline (placebo)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Non-obese (body mass index less than 30 kg/m2) *alternatively, individuals will be permitted to participate if they have a body mass index value below 35 kg/m2 but a waist circumference below 88 cm for females and 102 cm for males Systolic blood pressure <140 mmHg Diastolic blood pressure <90 mmHg Exclusion Criteria: Participants who have cardiac, respiratory, neurological, and/or metabolic illnesses Current or previous use of anti-hypertensive medications Any known history of renal or hepatic insufficiency/disease Pregnancy or breast feeding Current smokers, as well as individuals who regularly smoked within the past 3 years Individuals with a history of drug abuse Individuals who have an unexplained positive urine drug screen (e.g., some agents cause false-positive results, but when the agent is abstained for hours/days/weeks, the repeated drug screen is negative. One example could be an over-the-counter supplement)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: We plan to implement a crossover design. A parallel design is an alternative approach we may consider as the primary outcome is the effect of low dose ketamine on muscle sympathetic nervous system, for which a placebo administration may not be fully necessary.
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low Dose Ketamine<br> | Drug: Ketamine<br>* Low dose ketamine - Ketalar (Racemic Ketamine Hydrochloride) Saline - Isotonic/Normal Saline<br>|
| Placebo Comparator: Saline (placebo)<br> | Drug: Saline (placebo)<br>* Saline (placebo)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle Sympathetic Nerve Activity Burst Frequency | We will measure muscle sympathetic nerve activity (MSNA), quantified as burst frequency and/or incidence, using microneurography | This outcome will be assessed within one trial lasting up to approximately five hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial Blood Pressure | We will measure arterial blood pressure, quantified as systolic, mean, and/or diastolic pressure, using an automated monitor before and after administration of low dose ketamine. | This outcome will be assessed within one trial lasting up to approximately five hours |