Electronic Supplement ICM-2006-00135.R5
“Elimination of Daily Routine Chest Radiographs in a Mixed Medical – Surgical Intensive Care Unit” by Marleen E. Graat, Anke Kröner, Peter E. Spronk, Johanna C. Korevaar, Jaap Stoker, Margreeth B. Vroom, and Marcus J. Schultz
Costs analysis
The difference between the observed number and the projected number of CXRs was used to determine the impact on costs of the intervention. In our institution, costs of each CXR is €45, which includes costs for the film and supplies and costs for radiology technician time; fixed costs of equipment/administrative overhead were not included.
Using the ratio of 1.1 CXRs per patient day before the intervention, we projected that 3353 CXRs would have been obtained during phase 2. A total of 1268 CXRs was obtained, a decline of 2085 CXRs. A decline of 2085 CXRs during the 5–month period equals a cost savings of 2085 * €45 = €93.825 for phase 2 (= €18.765 per month).
However, part of cost per CXR is from technician time; if there is no corresponding change in employee full-time equivalents (FTE), this amount would have little meaning. In practice, however, there was a substantial decrease in the volume of CXRs during morning rounds caused by the intervention, and the radiology technicians were subsequently rescheduled to accommodate other times. The net effect of the rescheduling for peak times was a decline of ~0.4 technician time (3 radiology technicians were rescheduled ¾ hr/day, 7 days per week). Since costs of personnel varies, we were not able to calculate the real costs reduction. Second, abnormalities found on CXRs may – or may not – trigger additional interventions. The design of the study did not allow us to calculate alterations of costs associated with this change in a reliable way.
Figure legends
Figure E1. Averaged distribution of chest radiographs (CXRs) in phase 1 (open bars, 1437 on demand CXRs) and phase 2 (closed bars, 1267 on demand CXRs) over 24 hours. Daily-routine CXRs (in phase 1) were ignored.
Tables
Unit policy
Any admittance to the intensive care unit
Tracheal intubation
Suspected pneumothorax (e.g., subcutaneous emphysema)
New central venous catheter (in vena subclavia or vena jugularis)1
New other invasive devices
Left to the discretion of the attending supervisor
Oxygenation worsening
1, central venous lines are never changed over a guide wire
Table E2. On demand chest radiographs with unexpected predefined major abnormalities resulting in a change in management per admittance category
Diagnostic category / Medical / General
Surgery / Cardiopulmonary
Surgery / Neurosurgery / Other
Abnormalities / unexpected abnormalities resulting in a change in management / all unexpected abnormalities per category2
Total – phase 1
(% of all on demand CXRs per group) / N = 409
14/42
(3.4%/10.3%) / N = 253
8/26
(3.1%/10.3%) / N = 608
26/61
(4.3%/10.0%) / N = 114
8/15
(7.0%/13.2%) / N = 53
1/3
(1.9%/5.7%)
Total – phase 2
(% of all on demand CXRs per group) / N = 272
19*/51*
(7.0%/18.8%) / N = 402
21/43
(5.2%/10.7%) / N = 460
21/46
(4.6%/10.0%) / N = 122
3/16
(2.5%/13.1%) / N = 11
0/0
(0%/0%)
CXRs, chest radiographs
N = absolute numbers of CXRs per diagnostic category
*, P < 0.05 versus phase 1
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