Abstract:

Objective   To design and make an automatic control hypoxic chamber for the development and evaluation of the intermittent hypoxia animal model of children obstructive sleep apnea hypopnea syndrome(OSAHS). Methods   Twenty-four SD rats were randomly divided into 3 groups: control group, mild hypoxia group and severe hypoxia group. The latter two groups were raised in the intermittent hypoxic chamber.  By adjusting the parameters, the rats in mild hypoxia group and severe hypoxia group were moved to and fro straightly among the 3 carbins of the automatic control hypoxic chamber in order to achieve intermittent hypoxia. Finger type blood oxygen saturation sensor was used to measure the oxygen saturation in different hypoxia conditions. Results   When oxygen concentration in the hypoxic carbin reached 6%-8%, the rats in mild group stayed in the hypoxic carbin, transition cabin and animal cabin for 8 s, 2 s and 600 s respectively. After the above cycle was continuously repeated in 8 hours per day, average oxygen saturation of the rats in this group determined in the transition cabin reached (85.25±1.75)%. While, the rats in severe group stayed in the hypoxic carbin, transition cabin and animal cabin for 8 s, 2 s and 150 s respectively. After the above cycle was continuously repeated in 8 hours per day, average oxygen saturation of the rats in this group determined in the transition cabin reached (77.63±3.78)%. When the rats of the two groups returned into the animal cabin, their oxygen saturation were all between 98%-100%. Apnea-hypopnea index(AHI)in mild group was 6 times/h, and AHI in severe group was 24 times/h. Oxygen saturation, duration and frequency of hypoxic events were consistent with the mild and severe standard of children OSAHS. Conclusion   The self-developed automatic control hypoxic chamber can be used to establish animal models of intermittent hypoxia of children OSAHS.

Key words: Obstructive sleep apnea hypopnea syndrome； Automatic control； Intermittent hypoxia； Children； Animal model； Rats， Sprague-Dawley