Effects of Eliminating Daily Chest X-Rays in the ICU

Abstract & Commentary

By Saadia R. Akhtar, MD, MSc, Idaho Pulmonary Associates, Boise, is Associate Editor for Critical Care Alert.

Dr. Akhtar reports no financial relationship to this field of study.

Synopsis: This single center prospective observational study finds that the utility of a routine daily chest x-ray (CXR) for an ICU patient is quite limited. A change in practice to ordering CXR only when clinically indicated did not adversely impact patient outcome but reduced CXR volume and overall costs.

Source: Hendrikse KA, et al. Low Value of Routine Chest Radiographs in a Mixed Medical-Surgical ICU. Chest. 2007;132: 823-828.

A prospective observational study was conducted to assess diagnostic and therapeutic efficacies of a daily routine CXR and to evaluate the impact of discontinuing this practice. The setting was a 10-bed mixed medical-surgical ICU of a non-academic teaching hospital in The Netherlands. A daily CXR was obtained on every ICU patient every day for 1 year. These CXRs were read independently by radiologists; images and reports were not available to the patient's attending physicians unless there was a new potentially life-threatening finding (eg, tension pneumothorax).

If the attending physician requested a CXR for a specific clinical indication close to the time the daily study CXR was obtained, this CXR was released for view; if the clinical indication arose at a different time, a new CXR was performed and made available to the physician. The authors documented data on specific new or progressive radiological findings (eg, malpositioning of hardware, infiltrates, pneumothorax, etc) and patient management decisions (adjustment of hardware, change in medications or ventilator settings, etc.) that were defined a priori. Finally, after a 1-year study period, routine daily CXRs were discontinued and both clinician practice and outcomes were observed for another 6 months. Cost estimates were determined a priori for each CXR, and standard statistical methods were employed.

There were 559 admissions in 486 patients during the 1-year study period, accounting for a total of 1780 daily routine CXRs; 907 additional clinically indicated CXRs were performed. Only 4.4% (79) of the daily routine CXRs, vs 15.2% (138) of the clinically indicated CXRs, revealed new or progressive radiological findings. This was independent of intubation status or admission type (medical vs surgical). Similarly, only 1.9% (33) of the daily routine CXRs, but 17.9% (162) of the clinically indicated CXRs, led to a change in patient management.

During the follow-up 6 month phase, 433 clinically indicated CXRs were performed during 274 admissions for 250 patients. That is, the total number of CXRs per patient per day decreased by about 50%. There was an associated cost reduction of $99,000 per year. There was no change in ICU length of stay, readmission rate, or hospital mortality noted, although the study was not designed or powered to truly detect differences in cost, ICU length of stay, readmission or mortality.

Commentary

The ordering of a routine daily CXR for every ICU patient remains a common practice, despite prior work suggesting this may not be necessary.1,2 The authors of the present article reasoned that because previous studies had been somewhat limited in terms of size, setting (most had been conducted at academic centers) or lack of blinding of attending physicians to the findings of daily CXRs, further research was indicated. Their prospective observational study is large, set in a non-academic center, and does blind attending physicians to the findings on daily CXRs. The latter is the greatest strength of this work: it allows the authors to demonstrate more clearly and robustly that clinical course and management are not often altered by knowledge of results of daily routine CXRs.

As might have been expected, the findings on clinically-indicated CXRs were much more likely to impact the course of care. Furthermore, between the 1-year study period and the 6-month follow-up phase, the number of clinically-indicated CXRs requested did not change, suggesting that the attending physicians' medical practice, standards and decision-making process were largely unaffected by the presence or absence of daily routine CXRs.

The authors address the limitations of their work thoroughly. The ideal would be a similar study but conducted at multiple centers with a randomized, controlled design and powered to detect differences in clinical outcomes (length of stay, readmission, specific morbidities such as complications of a missed pneumothorax or delay in treatment of pneumonia, and mortality). However, taken together with the current body of literature on the limited utility or lack of utility of routine daily CXRs, Hendrikse et al's work reinforces the need to break this old habit.

A recently released study of accepted indications for CXRs in ICU patients surveyed 82 French intensivists and found that over 50% of them did not feel a daily routine CXR was needed in an intubated patient.3 I wonder what a similar survey in the U.S. would reveal about our beliefs and our practice.

References

  1. Graat ME, et al. Intensive Care Med. 2007;33:639-644.
  2. Krivopal M, et al. Utility of daily routine portable chest radiographs in mechanically ventilated patients in the medical ICU. Chest. 2003;123:1607-1614.
  3. Hejblum G, et al. A web-based Delphi study on the indications of chest radiographs for patients in intensive case units. Chest. 2007; Epub prior to print (PMID: 17989166).