Table 1.
Characteristics of patients and intensive care units (ICUs) by category of percentage of critical care registered nurses in each ICU.
| <50 % CCRN | 50–75% CCRN | >75% CCRN | p value | |
|---|---|---|---|---|
| Patient characteristics | N = 2360 | N = 7695 | N = 6563 | |
| Age in yearsa | 60.7 (18.0) | 61.1 (17.5) | 62.1 (17.2) | <0.001 |
| Men | 1401 (59.4%) | 4482 (58.2%) | 3768 (57.4%) | 0.24 |
| ICU admission category | <0.001 | |||
| Medical admission | 1594 (67.5%) | 4970 (64.6%) | 3113 (47.4%) | |
| Emergency surgical admission | 406 (17.2%) | 1379 (17.9%) | 1065 (16.2%) | |
| Elective surgery with planned ICU admission | 360 (15.3%) | 1346 (17.5%) | 2385 (36.3%) | |
| ICU admission diagnosis | <0.001 | |||
| Cardiac medical diagnoses | 305 (12.9%) | 960 (12.5%) | 611 (9.3%) | |
| Respiratory medical diagnoses (excl. pneumonia) | 212 (9.0%) | 660 (8.6%) | 334 (5.1%) | |
| Sepsis and other infections (incl. pneumonia) | 424 (18.0%) | 1378 (17.9%) | 844 (12.9%) | |
| Other medical diagnoses | 361 (15.3%) | 1191 (15.5%) | 738 (11.2%) | |
| Cardiothoracic & vascular surgery | 140 (5.9%) | 540 (7.0%) | 568 (8.7%) | |
| Coronary Artery Bypass Grafting and/or valve surgery | 134 (5.7%) | 514 (6.7%) | 882 (13.4%) | |
| Gastro-intestinal surgery | 204 (8.6%) | 733 (9.5%) | 799 (12.2%) | |
| Neurological and neurosurgical diagnoses | 118 (5.0%) | 502 (6.5%) | 529 (8.1%) | |
| Orthopaedic surgery | 44 (1.9%) | 183 (2.4%) | 392 (6.0%) | |
| Trauma | 271 (11.5%) | 565 (7.3%) | 363 (5.5%) | |
| Other surgical diagnoses | 147 (6.2%) | 469 (6.1%) | 503 (7.7%) | |
| COVID-19 pneumonitis | 105 (4.4%) | 297 (3.9%) | 106 (1.6%) | <0.001 |
| Illness severity scores | ||||
| Acute Physiology and Chronic Health Evaluation (APACHE) III/IV scorea | 54.1 (25.7) | 56.2 (25.2) | 52.0 (23.6) | <0.001 |
| Australian & New Zealand Risk of Death (ANZROD) percent (mean, median [IQR]) | 10.8, 2.9 (0.7–11.2) | 11.5, 3.1 (0.8–12.8) | 9.4, 1.8 (0.5–8.3) | <0.001 |
| Therapies provided in ICU | ||||
| Invasive ventilation | 903 (38.3%) | 3101 (40.3%) | 2639 (40.2%) | 0.19 |
| Renal replacement therapy | 163 (7.0%) | 562 (7.6%) | 291 (5.4%) | <0.001 |
| Extracorporeal membrane oxygenation | 32 (1.4%) | 44 (0.6%) | 13 (0.2%) | <0.001 |
| Inotropes | 1034 (44.2%) | 3763 (50.9%) | 2431 (45.4%) | <0.001 |
| Invasive ventilation, renal replacement or ECMO | 952 (40.3%) | 3297 (42.8%) | 2751 (41.9%) | 0.09 |
| Intensive Care Unit Characteristics | ||||
| Hospital classification | <0.001 | |||
| Public rural/regional (4 ICUs) | 702 (30%) | 1179 (15%) | 190 (3%) | |
| Public metropolitan (6 ICUs) | 748 (32%) | 2599 (34%) | 676 (10%) | |
| Public tertiary (5 ICUs) | 900 (38%) | 3496 (45%) | 3311 (50%) | |
| Private (5 ICUs) | 10 (0%) | 421 (5%) | 2386 (36%) | |
| Characteristics of the ICU and nursing skill-mix profile on the day of patient's admission to ICU (unless otherwise stated) | ||||
| Activity index of the ICU | 1.3 (0.5–1.7) | 1.4 (0.9–1.6) | 1.2 (0.7–1.5) | <0.001 |
| Occupancy (%)b | 88 (67–95) | 90 (77–95) | 85 (73–93) | <0.001 |
| Number of baseline ‘business as usual’ ICU bedsb | 10.0 (6.0–46.0) | 14.0 (10.0–25.0) | 17.0 (11.0–26.0) | <0.001 |
| Number of patients receiving 1:1 nursing in ICUb | 7.0 (2.0–47.7) | 8.5 (4.0–23.3) | 10.0 (3.0–21.3) | <0.001 |
| Number of COVID-19 patients in ICU on day of admissionb | 2.0 (0.0–6.7) | 1.3 (0.0–3.8) | 0.8 (0.0–2.0) | <0.001 |
| Number of Critical Care Registered Nursesb | 6.0 (3.0–28.0) | 9.0 (6.0–20.0) | 13.0 (7.0–22.0) | <0.001 |
| Number of early career/in training critical care nursesb | 5.0 (3.0–26.0) | 4.0 (2.0–9.0) | 2.0 (1.0–4.0) | <0.001 |
| Number of nurses without ICU experience redeployed into ICUb | 1.0 (0.0–5.0) | 0.0 (0.0–2.0) | 0.0 (0.0–0.0) | <0.001 |
| Number of nursing students & ‘non-nursing’ staff providing ICU bedside careb | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | <0.001 |
| Percentage of CCRN as proportion of all staff providing bed-side ICU careb | 44.1 (36.4–49.3) | 62.1 (54.5–70.0) | 84.6 (77.8–93.8) | <0.001 |
| Percentage of CCRN throughout patient's ICU admissionb | 44.5 (39.5–47.7) | 62.7 (55.6–69.1) | 83.3 (78.7–90.4) | <0.001 |
CCRN, Critical Care Registered Nurses; ICU, Intensive Care Unit. A vacant ICU bed is one that is not occupied by a patient but is available, equipped and can be staffed with 1:1 nursing ratio. A staffed ICU bed is equipped and can be staffed with 1:1 nursing ratio but may or may not be filled by a patient.
a
Data reported as mean (standard deviation).
b
Median (interquartile range); all other data reported as number (percentage).