From: Role of sleep on respiratory failure after extubation in the ICU
Normal sleep (N = 15) | Atypical or no REM sleep (N = 37) | P value | |
---|---|---|---|
Patient characteristics | |||
Age (years) | 71 [61–76] | 67 [58–76] | 0.34 |
Male sex, n (%) | 11 (73%) | 24 (65%) | 0.75 |
Body mass index (kg/m2) | 31 [27–37] | 28 [25–32] | 0.19 |
Simplified Acute Physiological Score II at admission (points) | 40 [30–57] | 50 [38–66] | 0.13 |
Duration of mechanical ventilation before extubation (days) | 4 [3–15] | 9 [6–16] | 0.14 |
Sedation before polysomnography (number of days) | 2 [1–6] | 4 [2–9] | 0.09 |
Sedation-free days at time of polysomnography (days) | 2 [2–6] | 3 [2–5] | 0.29 |
Difficult or prolonged weaninga, n (%) | 6 (40%) | 12 (32%) | 0.75 |
Respiratory parameters before extubation | |||
Maximal inspiratory pressure (cmH2O) | 55 [37–60] | 50 [36–62] | 0.73 |
P0.1 (cmH2O) | 4 [3, 4] | 3 [3, 4] | 0.04 |
pH, units | 7.45 [7.44–7.49] | 7.46 [7.43–7.49] | 0.96 |
PCO2 (mmHg) | 41 [39–47] | 41 [34–44] | 0.11 |
PaO2/FiO2 (mmHg) | 200 [183–276] | 256 [195–303] | 0.24 |
Ineffective cough, n (%) | 1 (7%) | 5 (14%) | 0.66 |
Abundant secretions, n (%) | 4 (27%) | 7 (19%) | 0.71 |
Clinical parameters at time of PSG | |||
Sequential Organ Failure Assessment (points) | 3.0 [2.0–3.5] | 3.0 [2.0–4.0] | 0.63 |
Richmond Agitation Sedation Scale (points) | 0 [0–0] | 0 [0–0] | 0.53 |
Intensive care delirium screening checklist (points) | 0 [0–0] | 1 [0–2] | 0.086 |
Delirium, n/n assessed (%) | 2/14 (14%) | 6 (16%) | > 0.99 |
Medical Research Council (MRC) score (points) | 60 [57–60] | 48 [33–59] | 0.01 |
ICU-acquired weakness (MRC < 48), n/n total (%) | 2/12 (17%) | 15/32 (47%) | 0.09 |
Prophylactic noninvasive ventilation, n (%) | 10 (67%) | 16 (43%) | 0.22 |
Sleep quantity | |||
Duration of polysomnography recording (h) | 16.9 [15.5–17.5] | 16.2 [14.2–17.2] | 0.27 |
Sleep duration (h) | 4.2 [3.5–5.0] | 1.7 [0.9–3.4] | < 0.001 |
Sleep efficiency (%) | 25 [21–30] | 11 [6–18] | < 0.001 |
Duration of light or atypical sleep (min) | 129 [70–214] | 87 [44–123] | 0.12 |
Duration of deep sleep stage 3 (min) | 99 [40–120] | 4 [0–36] | < 0.001 |
Duration of REM sleep stage (min) | 13 [10–24] | 0 [0–0] | < 0.001 |
Sleep quality | |||
Absence of deep sleep, n (%) | 0 (0%) | 15 (41%) | 0.002 |
Absence of REM sleep, n (%) | 0 (0%) | 33 (89%) | < 0.001 |
Atypical sleep, n (%) | 0 (0%) | 10 (27%) | 0.046 |
Pathological wakefulness, n (%) | 1 (7%) | 11 (30%) | 0.14 |
Altered EEG reactivity at eye-opening test, n/n assessed (%) | 3/14 (21%) | 12/34 (35%) | 0.50 |
Sleep fragmentation | |||
Arousals and awakenings, events per hour of sleep | 37 [22–40] | 42 [24–50] | 0.44 |
Average sound pressure level, decibels | 58 [55–64] | 57 [55–59] | 0.47 |
Sound level events above 60 decibels, n events/h | 25 [18–41] | 28 [20–37] | 0.85 |
Outcomes | |||
Post-extubation respiratory failure, n (%) | 2 (13%) | 10 (27%) | 0.47 |
Reintubation in ICU, n (%) | 1 (7%) | 7 (19%) | 0.41 |
Mortality in ICU, n (%) | 0 (0%) | 1 (3%) | > 0.99 |