Table 2:
Patient and resident outcomes: overall and by overnight duty schedule
| Outcome | Duty schedule; no. (per 1000 patient-days)* | p value | |||
|---|---|---|---|---|---|
| All | 24-h night | 16-h night | 12-h night | ||
| Patients | |||||
| Adverse events† | 464 (78.7) | 166 (81.3) | 126 (76.3) | 172 (78.2) | 0.7 |
| Increased hospital stay | 93 (15.8) | 37 (18.1) | 15 (9.1) | 41 (18.6) | 0.5 |
| Disability | |||||
| None at discharge | 151 (25.6) | 59 (28.9) | 39 (23.6) | 53 (24.1) | 0.9 |
| Present < 1 mo after discharge | 283 (48.0) | 102 (49.9) | 78 (47.2) | 103 (46.8) | 0.5 |
| Present ≥ 1 mo after discharge | 20 (3.4) | 3 (1.5) | 4 (2.4) | 13 (5.9) | 0.3 |
| Errors‡ | |||||
| Of commission | 41 (7.0) | 11 (5.4) | 14 (8.5) | 16 (7.3) | 0.6 |
| Of omission | 246 (41.7) | 85 (41.6) | 67 (40.6) | 94 (42.7) | > 0.9 |
| Preventable adverse events† | 8 (1.4) | 1 (0.5) | 0 (0) | 7 (3.2) | 0.1 |
| ICU mortality, no. (%) | 160 (16.5) | 57 (18.3) | 50 (17.1) | 53 (14.4) | 0.2 |
| Residents | |||||
| Stanford Sleepiness Scale§ | |||||
| Total no. of measurements (while awake) | 1726 | 614 | 478 | 634 | |
| Day (8 am, noon, 4 pm), no. of measurements | 1286 | 468 | 350 | 468 | |
| Median score (IQR) | 2 (2–3) | 2 (1–3) | 2 (2–3) | 2 (2–3) | |
| Mean score ± SD | 2.39 ± 1.13 | 2.33 ± 1.20 | 2.61 ± 1.17 | 2.30 ± 0.99 | 0.3 |
| Night (8 pm, midnight, 4 am), no. of measurements | 440 | 146 | 128 | 166 | |
| Median score (IQR) | 2 (2–3) | 3 (2–4) | 2 (2–3) | 2 (2–3) | |
| Mean score ± SD | 2.72 ± 1.37 | 3.06 ± 1.57 | 2.73 ± 1.24 | 2.42 ± 1.21 | 0.2 |
| At 4 am | |||||
| No. (%) of residents asleep¶ | 42 (28) | 15 (32) | 10 (21.3) | 17 (29) | |
| No. of measurements on Stanford Sleepiness Scale | 108 | 36 | 37 | 35 | |
| Stanford Sleepiness Scale, mean score ± SD | 3.74 ± 1.51 | 4.08 ± 1.66 | 3.81 ± 1.24 | 3.31 ± 1.55 | 0.2 |
| End-rotation Maslach Burnout Inventory** | |||||
| No. of residents providing data | 41 | 13 | 14 | 14 | |
| Depersonalization domain, mean score ± SD | 11.9 ± 6.2 | 12 ± 6.9 | 12.2 ± 7.1 | 11.6 ± 5.0 | > 0.9 |
| No. (%) with high burnout by depersonalization | 24 (59) | 6 (46) | 9 (64) | 9 (64) | 0.7 |
| Emotional exhaustion domain, mean score ± SD | 26.8 ± 10.3 | 28 ± 11.1 | 27.1 ± 9.5 | 25.4 ± 11.0 | 0.8 |
| No. (%) with high burnout by emotional exhaustion | 23 (56) | 7 (54) | 8 (57) | 8 (57) | > 0.9 |
| Personal accomplishment domain, mean score ± SD | 34.6 ± 6.8 | 34.7 ± 6.6 | 33.1 ± 8.5 | 36.0 ± 5.4 | 0.6 |
| No. (%) with high burnout by personal accomplishment | 16 (39) | 7 (54) | 6 (43) | 3 (21) | 0.2 |
| Somatic symptoms,†† no. of assessments | 387 | 138 | 114 | 135 | |
| Most severe symptoms, mean ± SD | 2.08 ± 0.87 | 2.38 ± 0.91 | 1.86 ± 0.87 | 1.96 ± 0.77 | 0.05 |
| Symptoms ≥ moderate severity, mean ± SD per report | 0.62 ± 1.24 | 1.15 ± 1.71 | 0.38 ± 0.75 | 0.28 ± 0.73 | 0.04 |
| Symptoms < moderate severity, no. (%) of assessments | 274 (71) | 80 (58) | 84 (74) | 110 (81) | |
| Continuity survey‡‡ | |||||
| No. of responses from residents | 90 | 32 | 26 | 32 | |
| No. of days’ care by residents, mean ± SD | 2.34 ± 1.19 | 2.16 ± 1.19 | 2.73 ± 1.25 | 2.21 ± 1.10 | 0.1 |
| No. of responses from nurses | 123 | 41 | 34 | 48 | |
| No. of days’ care by nurses, mean ± SD | 1.58 ± 0.87 | 1.78 ± 0.91 | 1.47 ± 0.86 | 1.48 ± 0.82 | 0.2 |
Note: ICU = intensive care unit, IQR = interquartile range, SD = standard deviation.
Except where indicated otherwise.
Adjustment for Acute Physiology Assessment and Chronic Health Evaluation (APACHE) score was performed for adverse events (p = 0.6), preventable adverse events (p = 0.4) and mortality (p = 0.6). We report results for the comparison of 12- and 24-hour schedules for evaluation of preventable adverse events, as models with the 16-hour schedule (zero events) did not converge. Adjustment for APACHE score did not change the p values for the occurrence and persistence of disability (all p > 0.3).
Adverse events were classified as errors of omission or errors of commission when the preventability rating was 2 or more on the 6-point scale.
The Stanford Sleepiness Scale associates the following numeric values with descriptions of sleepiness: 1 = feeling active, vital, alert or wide awake; 2 = functioning at high levels, but not at peak, able to concentrate; 3 = awake but relaxed, responsive but not fully alert; 4 = somewhat foggy, let down; 5 = foggy, losing interest in remaining awake, slowed down; 6 = sleepy, woozy, fighting sleep, preferring to lie down; 7 = no longer fighting sleep, anticipating sleep onset soon, having dream-like thoughts. An additional category, “I was asleep at the time of assessment,” was used for study coding purposes, but these ratings were excluded from analyses of the Stanford Sleepiness Scale.
Residents reported being asleep on 2 occasions other than at 4 am: once at midnight and once at noon.
Overall (i.e., separate from rotations) post hoc comparison of start and end-rotation Maslach Burnout Inventory domain scores showed a significant decrease for the personal accomplishment domain (1.8, 95% confidence interval [CI] 3.5 to 0.03) and statistically insignificant increases for the emotional exhaustion domain (0.88, 95% CI −1.5 to 3.3) and the depersonalization domain (0.24, 95% CI −1.3 to 1.8).
Residents who were on duty in the ICU indicated which of the following 14 symptoms they had experienced in the past 24 hours: headache, eye pain, blurred vision, light-headedness, anxiety, nausea, vomiting, diarrhea, epigastric pain, other abdominal pain, palpitations, chest pain, musculoskeletal pain and swollen feet. Symptom severity was rated as the worst of none = 1, mild = 2, moderate = 3, moderately severe = 4 and severe (constant distraction) = 5.
Each week, the nurse and resident providing care to each of 2 randomly selected patients completed the continuity survey. Data presented here are based on responses to the question, “In the last 7 days, how many days have you looked after this patient?”