Table 3 Comparison of patients who developed post-extubation respiratory failure and those who succeeded extubation with no respiratory failure
From: Role of sleep on respiratory failure after extubation in the ICU
No respiratory failure (N = 40) | Post-extubation respiratory failure (N = 12) | P value | |
|---|---|---|---|
Patient characteristics | |||
Age (years) | 68 [59–76] | 65 [58–72] | 0.52 |
Male sex, n (%) | 27 (67%) | 8 (67%) | 0.99 |
Body mass index (kg/m2) | 30 [25–33] | 30 [25–37] | 0.47 |
Simplified Acute Physiological Score II at admission (points) | 48 [36–62] | 51 [37–59] | 0.94 |
Duration of mechanical ventilation before extubation (days) | 8 [4–16] | 10 [8–16] | 0.36 |
Sedation before polysomnography (n days) | 3 [2–8] | 7 [2–11] | 0.35 |
Sedation-free days at time of polysomnography (n days) | 3 [2–5] | 4 [1–6] | 0.96 |
Difficult or prolonged weaning, n (%) | 16 (40%) | 2 (17%) | 0.18 |
Respiratory parameters before extubation | |||
Maximal inspiratory pressure (cmH2O) | 56 [37–64] | 34 [29–50] | 0.02 |
P0.1 (cmH2O) | 3 [3, 4] | 3 [3, 4] | 0.56 |
pH | 7.45 [7.43–7.48] | 7.48 [7.47–7.50] | 0.10 |
PCO2 (mmHg) | 41 [36–46] | 40 [35–41] | 0.16 |
PaO2/FiO2 (mmHg) | 253 [197–314] | 244 [185–262] | 0.34 |
Ineffective cough, n (%) | 3 (7%) | 3 (25%) | 0.13 |
Abundant secretions, n (%) | 9 (22%) | 2 (17%) | 0.99 |
Clinical parameters at time of PSG | |||
Sequential Organ Failure Assessment (points) | 3 [2–4] | 4 [2–5] | 0.12 |
Richmond Agitation Sedation Scale (points) | 0 [0–0] | 0 [0–0] | 0.79 |
Intensive care delirium screening checklist (points) | 0 [0–1] | 1 [0–4] | 0.26 |
Delirium, n/n assessed (%) | 4/39 (10%) | 4/12 (33%) | 0.08 |
Medical Research Council (MRC) score (points) | 54 [37–60] | 45 [29–60] | 0.47 |
ICU-acquired weakness (MRC < 48), n/n total (%) | 11/34 (32%) | 6/10 (60%) | 0.15 |
Prophylactic noninvasive ventilation, n (%) | 20 (50%) | 6 (50%) | 0.99 |
Sleep quantity | |||
Duration of polysomnography recording (h) | 16.4 [14.6–17.3] | 16.8 [15.8–17.4] | 0.71 |
Sleep duration (h) | 2.0 [1.1–3.8] | 3.2 [2.0–4.4] | 0.34 |
Sleep efficiency (%) | 15 [7–23] | 20 [11–27] | 0.32 |
Duration of light or atypical sleep, min | 83 [44–177] | 103 [83–144] | 0.53 |
Duration of deep sleep stage 3 (min) | 14 [0–50] | 45 [4–99] | 0.16 |
Duration of REM sleep stage, min | 0 [0–12] | 0 [0–1] | 0.42 |
Sleep quality | |||
Absence of deep sleep, n (%) | 24 (60%) | 9 (75%) | 0.50 |
Absence of REM sleep, n (%) | 13 (33%) | 2 (17%) | 0.47 |
Atypical sleep, n (%) | 8 (20%) | 2 (17%) | 0.99 |
Pathological wakefulness, n (%) | 10 (25%) | 2 (17%) | 0.71 |
Altered EEG reactivity at eye-opening test, n/n assessed (%) | 12/37 (32%) | 3/11 (27%) | 0.99 |
Sleep fragmentation | |||
Arousals and awakenings, events per hour of sleep | 27 [16–36] | 21 [13–28] | 0.42 |
Average sound pressure level, decibels | 56 [54–59] | 60 [57–52] | 0.19 |
Sound level events above 60 decibels, n events/h | 25 [18–34] | 39 [29–39] | 0.19 |