Utilization, efficiency, and safety of the intermediate care unit for the three periods
| Period of admission | Period I: open format IMCU January 2001–September 2005 | Period II: closed format IMCU April 2006–December 2010 | Period III: joint format IMCU July 2011–December 2015 | P values* | ||
| Number of beds available | 4 | 5 | 6+1† | |||
| Utilization | Total admissions (n=8894) | 2495 | 3137 | 3262 | ||
| Average number of admissions per year | 526 | 660 | 725 | |||
| Admissions for specific interventions‡ (%) | 55 (2.25) | 97 (3.13) | 127 (3.91) | |||
| Surgical patients (%) | 2371 (96.97) | 2980 (96.22) | 3191 (97.91) | <0.001 | ||
| Sex, male (%) | 1606 (64.37) | 2052 (65.41) | 2121 (65.02) | 0.715 | ||
| Age, mean (CI) | 57.71 (56.98 to 58.42) | 59.27 (58.65 to 59.86) | 61.60 (61.02 to 62.16) | <0.001 | ||
| Nursing workload, TISS-28, mean (CI) | 18.40 (18.17 to 18.63) | 19.56 (19.35 to 19.78) | 21.64 (21.43 to 21.85) | <0.001 | ||
| Admission duration, in hours, mean (BCA CI) | 66.95 (62.54 to 72.87) | 67.99 (64.74 to 72.53) | 53.84 (51.53 to 56.64) | < 0.001 | ||
| Readmissions (%) | From ward | 103 (4.13) | 151 (4.81) | 190 (5.82) | 0.012 | |
| From ICU | 103 (4.13) | 96 (3.06) | 201 (6.16) | <0.001 | ||
| Time until readmission, in days, mean (BCA CI) | From ward | 3.78 (3.16 to 4.55) | 3.69 (3.16 to 4.25) | 4.27 (3.79 to 4.82) | 0.176 | |
| From ICU | 4.66 (4.25 to 5.09) | 4.66 (4.26 to 5.08) | 4.66 (4.25 to 5.08) | 0.581 | ||
| Efficiency | Overtriaged admissions (%) | From ICU | 248 (9.94) | 327 (10.42) | 344 (10.55) | 0.740 |
| From recovery | 222 (8.90) | 251 (8.00) | 359 (11.01) | <0.001 | ||
| Safety | Early (<24 hours) transfer to ICU (%) | 87 (3.49) | 91 (2.90) | 105 (3.22) | 0.456 | |
| Readmissions <24 hours, from ward (%) | 12 (0.48) | 29 (0.92) | 37 (1.13) | 0.029 | ||
| Mortality (unplanned), total (%) | ||||||
| Without treatment restrictions (%) | 10 (0.40) | 8 (0.26) | 6 (0.18) | 0.285 | ||
| With a non-ICU policy (%) | 8 (0.32) | 6 (0.19) | 0 (0.00) | 0.002§ | ||
This table shows the utilization, efficiency, and safety of the IMCUs in time periods with different management formats of the IMCU and the ICU. The management format open means that the attending surgeon remained in charge, closed means that the anesthetist was in charge, and joint means that the IMCU was run by dedicated trauma surgeons with additional training in the field of critical care. Overtriage is defined as transfer to the hospital ward within 24 hours after admission.
*These p values are based on analysis of variance tests for continuous variables and χ2 tests of independence for categorical and dichotomous variables. P-values <0.05 are displayed in bold
†In 2011 this was supplemented with an additional procedure bed (6+1), used for specific interventions.3
‡Specific interventions such as the placement of a chest tube or central venous catheter.
§Fisher’s exact test was used since expected values were less than 5.
BCA , Bootstrapped Confidence Interval; ICU, intensive care unit;IMCU, intermediate care unit; TISS, Therapeutic Intervention Scoring System.