HOBBIT 3: Mental Exercises and Temporal Alteration

In the HOBBIT-trial by Vakaet et al. A protocol was developed to increase breath-hold time using (voluntary) hyperventilation and oxygenation to achieve DIBH times around 3 minutes. Multiple non-medical interventions are being investigated to prolong a L-DIBH that are feasible in clinical practice. One of these methods will be to alter the time perception of the subjects. It has been noted in multiple studies (both medical and not) that slowing a person's perception of time results in an increase in breath-hold time. This alteration in time perception can be achieved with the use of a slowed clock as well as the usage of mental or physical exercises to preoccupy the subjects. Volunteers will then be randomised into either the standard arm or the intervention arm. The intervention arm will follow standard protocol regarding DIBH preparation, though during the L-DIBH they will be asked to perform a simple mental exercise on a tablet. After 2 sessions of 3 L-DIBHs each, there will be a cross-over to the other arm in order to ascertain comfort and preference with each technique.

Sex

Female

Minimum age

18 Years

Inclusion Criteria:

* Volunteer
* Karnofsky index of at least 90
* Able to perform a single DIBH of at least twenty seconds without assistance
* Age ≥ 18 years
* Informed consent obtained, signed and dated before specific protocol procedures
* Female

Exclusion Criteria:

* Pregnant women
* Volunteers above WHO Obesity class II (BMI\>35kg/m²)
* Subjects on oxygen treatment during day or night
* COPD or Asthma patients
* Volunteers with pulmonary hypertension
* Gastric tube present
* Smoking
* Previous and substantial breath-holding experience in the past year (e.g., diver, etc.)
* Mental condition rendering the volunteer unable to understand the nature, scope and possible consequences of the study

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