88 British Journal of Oral and Maxillofacial Surgery
followed 2 minutes later by midazolam again titrated to a similar patient response. Local anaesthesia was then achieved and surgery commenced (Fig. 1). A hypoxic episode was deemed to have occurred if the oxygen saturation fell below a predetermined value, irrespective of the length of time ,for which this persisted. Severity of hypoxia was classified according to the criteria of Smith et al. (1989) shown in Figure 2. Differences in severity of hypoxia were compared using the chi-squared test. As the data was skewed, the difference in the incidence of hypoxia in the two groups was compared using the Mann-Whitney Utest. The mean dose of midazolam required to sedate patients was also compared in the two groups and analysed using the student t-test.
RESULTS Fifteen of the patients in the midazolam group experienced some degree of hypoxia whilst 18 patients receiving the combination technique experienced similar events. The degree of hypoxia experienced by patients in each group is shown in Figure 3. It can be seen that most of the patients in the midazolam group experienced mild hypoxic episodes and that only three patients (15%) experienced a moderate or severe episode. However, only six patients in the combination agent group experienced mild hypoxia, and the majority, 12 (60%), experiencing moderate or severe episodes of hypoxia. These differences were found to be significant (p
followed 2 minutes later by midazolam again titrated to a similar patient response. Local anaesthesia was then achieved and surgery commenced (Fig. 1). A hypoxic episode was deemed to have occurred if the oxygen saturation fell below a predetermined value, irrespective of the length of time ,for which this persisted. Severity of hypoxia was classified according to the criteria of Smith et al. (1989) shown in Figure 2. Differences in severity of hypoxia were compared using the chi-squared test. As the data was skewed, the difference in the incidence of hypoxia in the two groups was compared using the Mann-Whitney Utest. The mean dose of midazolam required to sedate patients was also compared in the two groups and analysed using the student t-test.
RESULTS Fifteen of the patients in the midazolam group experienced some degree of hypoxia whilst 18 patients receiving the combination technique experienced similar events. The degree of hypoxia experienced by patients in each group is shown in Figure 3. It can be seen that most of the patients in the midazolam group experienced mild hypoxic episodes and that only three patients (15%) experienced a moderate or severe episode. However, only six patients in the combination agent group experienced mild hypoxia, and the majority, 12 (60%), experiencing moderate or severe episodes of hypoxia. These differences were found to be significant (p
