Page 58 - Effects of radiotherapy and hyperbaric oxygen therapy on oral microcirculation Renee Helmers

Chapter 3
outflow nozzle connections to evenly dissipate oxygen in the entire pushcart- container, each of the 6 individual compartments could effectively contain 100% oxygen and were completely isolated once the installation of a 1 cm- thick poly(methyl methacrylate) (PMMA) or acrylic glass cover was lowered and fitted on the top of the entire pushcart-container. A photograph of the transport pushcart-container, compartment oxygenations test using a compact air oxygen-measuring device (GOX 100, Geisinger Electronic GmbH, Regenstauf, Germany), and use of the pushcart-container during a running experiment is illustrated in Figure 1.
Figure 1. A custom-built transport pushcart-container with its oxygen inflow and outflow tube connections stationed in the hyperbaric tank (Panel A). To test if each compartment was able to properly contain 100% oxygen, a compact air oxygen measuring instrument was used (Panel B); the oxygen meter registered 94.8% oxygen in the posterior compartments (i.e. most distal from oxygen inflow source) after 10 minutes of switching on the oxygen inflow. A photograph illustrating an actual experimental procedure during HBOT is presented in Panel C.
Preparation for the HBOT experimental procedure was initiated everyday at 11:00 in the morning by withdrawing of food and drink from each animal at their normal housing establishment until the start of the HBOT protocol onsite. This was intended to produce an urge to drink as a response from mild dehydration in order to stimulate deglutition for equalization of pressure in all animals during the pressurization phase of the diving protocol. Control animals were treated according to the same procedures, but did not undergo HBOT. Upon arrival at the hyperbaric tank site, the pushcart-container was rolled carefully into the tank and positioned directly under a ceiling-rack from which oxygen supply was obtained.
Fifteen minutes prior to commencing the hyperbaric diving protocol, solid food and drinking gel was provided to each animal and saturation of 100% oxygen in all compartments was initiated. An investigator was present in the hyperbaric tank during every experiment to monitor the animals during the HBOT procedure. Three in-tank investigators (RH, DMJM, and SH) were required
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