Ketogenic Diet for Reduction of CNS Oxygen Toxicity in Working Divers

• ClinicalTrials.gov Identifier: NCT03433261
• Recruitment Status: Completed
• First Posted: February 14, 2018
• Last Update Posted: December 14, 2021
• Sponsor: Duke University
• Collaborator: United States Department of Defense
• Information provided by (Responsible Party): Duke University

Study Description

Brief Summary:

The purpose of this research study is to understand the effect of nutritional ketosis on CNS oxygen toxicity in undersea divers. The investigators hope this will provide a starting point to develop methods for improving the safety of Navy divers, warfighters and submariners.

Condition or disease	Intervention/treatment	Phase
CNS Oxygen Toxicity, Ketogenic Diet	Dietary Supplement: Ketogenic Diet	Not Applicable

Detailed Description:

Participants in the study will undergo a physical exam and testing as well as training on cognitive testing software as part of the screening process. Eligible subjects will be assigned a normal diet or a ketogenic diet (a diet high in fat/protein and low in carbohydrates) for three days before testing. Subjects will be immersed in water to the shoulders, inside a hyperbaric (high pressure) chamber while breathing 100% oxygen at increased atmospheric pressure, and doing cycling exercise. Testing on the cognitive software, as well as blood sampling and physical monitoring will be done while in the chamber. All tests and procedures will be completed again at least one week later with the diet not assigned for the first session.

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 91 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Intervention Model Description: Each subject will randomize to one of two arms and will crossover to the other arm at least one week later.
• Masking: Double (Investigator, Outcomes Assessor)
• Masking Description: Neither the investigator nor the outcomes assessor will no the ketone level of the participant during either arm of the study
• Primary Purpose: Prevention
• Official Title: Ketogenic Diet for Reduction of Oxygen Toxicity in Working Divers
• Actual Study Start Date: March 1, 2018
• Actual Primary Completion Date: October 30, 2021
• Actual Study Completion Date: October 30, 2021

Arms and Interventions

Arm	Intervention/treatment
No Intervention: Normal Diet; The participant will eat their usual diet for at least 72 hrs prior to the experiment, document their diet during that time and be tested for ketone level immediately prior to the experiment.
Experimental: Ketogenic Diet; The participant will follow a ketogenic diet for 72 hrs prior to the experiment and consume a ketone supplement 60 minutes prior to the experiment. They will document their diet and be tested for ketone level immediately prior to the experiment.	Dietary Supplement: Ketogenic Diet; Eat a ketogenic diet (low carbohydrate, high fat diet) for 72 hrs prior to the experiment and consume a dietary ketone supplement 60 minutes before the experiment.

Outcome Measures

Primary Outcome Measures :

1. Time to First Manifestations of CNS Oxygen Toxicity [ Time Frame: 2 hrs ]
   Time to the first manifestation of CNS Oxygen Toxicity: visual or hearing changes, nausea, twitching, irritability, dizziness, convulsions or change consistent with possible CNS Oxygen Toxicity.

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 50 Years (Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

• Males & females between 18 and 50 years old
• Able to pedal a bicycle ergometer continuously for 15 minutes
• Non-smoker
• No history of cardiovascular disease, including coronary artery disease, valvular disease, cardiomyopathy or hypertension.
• No history of lung disease

Exclusion Criteria:

• Prolonged QTc on initial ECG
• Currently pregnant or attempting to become pregnant.

• Have a history of:

  1. Smoking
  2. Coronary artery disease
  3. Hypertension
  4. Seizures
  5. Exercise intolerance
  6. Psychiatric disorder
  7. Previous pneumothorax or pneumomediastinum
  8. Hypo or hyperglycemia
  9. Diabetes
• Regularly take any medications which may alter heart rate, blood pressure, neurotransmitter function, mood or affect.

Contacts and Locations

Locations

United States, North Carolina

Duke University Hospital

Durham, North Carolina, United States, 27710

Sponsors and Collaborators

Duke University

United States Department of Defense

More Information

• Responsible Party: Duke University
• ClinicalTrials.gov Identifier: NCT03433261
• Other Study ID Numbers: Pro00070499
• First Posted: February 14, 2018
• Last Update Posted: December 14, 2021
• Last Verified: November 2021

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No

Additional relevant MeSH terms:

Hyperoxia; Signs and Symptoms, Respiratory