RESULTS
During the research period, 101 patients were admitted for cardiac
surgery, of these 22 were excluded for the following reasons: 03
required surgical reintervention before extubation, 10 remained on
mechanical ventilation for more than 24 hours, 5 refused to participate
in the research, 2 were death before extubation and 1 it was not
possible to collect blood gas data before NIV (Figure 1). Thus, 79
patients were studied, with no loss of follow-up after randomization, 42
were allocated to the conventional NIV group and 37 to the group
immediately after extubation.
Table 1 shows the clinical and surgical characteristics of the patients.
Among these, the male gender prevailed with 46 patients (58.22%), with
a mean age of 65 ± 9 years, with arterial hypertension being the most
prevalent comorbidity. The other variables are shown in table 1.
Significance was verified in FiO2 and in the PaO2/FiO2 ratio. The FiO2
variables in the post-intervention, in the conventional group, it had
0.43 ± 0.07 and in the intervention group 0.30 ± 0.10, with a p-value of
0.01. With regard to FiO2 one day later, the conventional group had 0.40
± 0.09 and in the intervention group 0.30 ± 0.05, with a p-value of
0.04. The value of the PaO2 / FiO2 ratio in the intervention group was
higher 95% CI 75 (+45 to +91) right after NIV and one day later 69
(95% CI +33 to +82). The other values are shown in table 2.
Table 3 shows the functional outcomes between the groups studied, at
different times of the research. FIM and MRC did not show any
statistically significant variation when comparing the groups and the
preoperative period with hospital discharge, but there was a significant
reduction when analyzing the preoperative and discharge from the ICU.
The group of patients who underwent immediate NIV presented better
performance on the 6MWT, loss of 51 ± 36 meters, when compared to the
conventional group that had a loss in the distance covered of 95 ± 40
meters (p <0.01). In the 6MWT the difference between the
groups was 44 (95% CI +25 to +59).
Regarding post-surgical pulmonary complications, Table 4 shows the
result between the groups. The only variable that obtained statistical
significance was reintubation, resulting from 5 patients who underwent
NIV one day after extubation and 1 who underwent NIV immediately after
extubation (p = 0.01).