Deimplementation of Routine Chest X-rays in Adult Intensive Care Units

Semistructured Interviews

Based on the direct observations, we developed semistructured interview questions to further evaluate provider perspectives (eg, “Do you believe ICU patients need a daily CXR?”) and constructs aligning with CFIR (eg, “intervention source—internally vs externally developed;” see Supplemental Material, 4 – Interview Questions).

Stakeholders from both ICUs were recruited through e-mail and in-person requests to participate in semistructured interviews. In the CVICU, we interviewed critical care physicians, anesthesia critical care fellows, and ACNPs. In the MICU, we interviewed medical students, interns, residents, critical care fellows, attending intensivist physicians, and ACNPs. We also interviewed X-ray technologists who routinely perform portable films in the units.

RESULTS

Quantitative Results

We analyzed CXR ordering data from a period of 86 weeks, comprising 50 weeks of baseline data, three weeks of washout period, and 33 weeks following the introduction of the intervention. In both ICUs, patient characteristics were similar in the baseline and intervention periods (Table 1).

Cardiovascular Intensive Care Unit

The median baseline CXR ordering rate in the CVICU was 1.16 CXRs per patient per day, with interquartile range (IQR) 1.06-1.28. During the intervention period, the rate dropped to 1.07 (IQR 0.94-1.21; P < .001; Table 2). The time-series analysis suggested an essentially flat trend during the baseline period, followed by a small but significant drop in ordering rates during the intervention period (P < .001; Table 3 and Figure 1). Ordering rates appeared to increase slightly over the course of the intervention period, but this slight upward trend was not significantly different from the flat trend seen during the baseline period.

Medical Intensive Care Unit

For both physician and ACPN teams, the median baseline CXR ordering rates in the MICU were much lower than the baseline rate in the CVICU (Table 2). For the MICU physician care team, the baseline CXR ordering rate was 0.60 CXRs per patient per day (IQR 0.48-0.73). For the ACNP team, the median rate was 0.39 CXRs per patient per day (IQR 0.21-0.57). Both rates stayed approximately the same during the intervention period (Table 2). The time-series analysis suggested a statistically significant but very slight downward trend in CXR ordering rates during the baseline period, in the physician (P = .011) and ACNP (P = .022) teams (Table 3, Figure 2). Under this model, a small increase in CXR ordering initially occurred during the intervention period for both physician and ACNP teams (P = .010 and P = .055, respectively), after which the rates declined slightly. Trends in ordering rates during the intervention period were not significantly different from the slight downward trends seen during the baseline period.

Qualitative Results

We identified 25 of 39 CFIR constructs as relevant to the initiative (see Supplemental Materials, 3 – CFIR Table.) We determined the major facilitators of deimplementation to be peer champion discussions about CXR ordering on rounds and weekly data feedback, particularly if accompanied by in-person follow-up.

Major differences between the units pertained to the “inner setting” domain. Compared with the CVICU, which is staffed by a stable group of ACNPs, two of the three MICU teams are staffed by resident physicians who rotate on and off service. CVICU providers and ACNPs in the MICU reported significant investment in the CXR and other QI interventions. Conversely, resident physicians, who complete two- to four-week MICU rotations, reported less investment as well as greater fatigue and competing priorities. Some MICU residents began ignoring weekly feedback, citing “e-mail fatigue” and the lack of in-person follow-up or didactic sessions associated with the reports.

We also noted differences in CXR ordering rationales and decisions between the units. Generally, residents in the MICU and ACNPs in the CVICU made decisions to order CXRs. However, decisions were influenced by the expectations of attending physicians. While CVICU providers tended to order CXRs reflexively as part of morning labs, MICU providers—in particular, ACNPs who had been trained on indications for proper CXR ordering—generally ordered CXRs for specific indications (eg, worsening respiratory status). Of note, MICU ACNPs reported the use of bedside ultrasound as an alternate imaging modality and a reason for their higher threshold to order CXRs.

Deimplementation barriers in both units included the need to identify goal CXR ordering rates and the intervention’s limited visibility. To address these barriers, we conducted PDSA cycles and used the CFIR and ERIC to generate potential solutions.²⁴ We established a goal of a 20% absolute reduction in the CVICU, added monthly CXR rates to weekly e-mail reports to better account for variations in patient populations and ordering practices, and circulated materials to promote on-demand CXR ordering. Promotional materials contained guidelines on CXR ordering and five “Frequently Held Misconceptions” about ordering practices with succinct, evidence-based explanations (see Supplemental Material, 2 – CXR Flyer).

Approximately four months after the start of intervention, some CVICU physicians became concerned that on-demand CXR ordering might be inappropriate for high-risk surgical patients, including those who are undergoing or have undergone heart transplants, lung transplants, or left-ventricular assist device placement. This concern arose following two adverse outcomes, which were not attributed to the CXR initiative, but which heightened concerns about patient safety. A rise in CXR ordering then occurred, and CVICU providers requested that we perform an analysis of these high-risk groups. While segmented linear regression in this subgroup suggested that average daily CXR ordering rates did decrease among the high-risk group at the start of the intervention period (P = .001), the difference between the rates in the two periods was not significant using the Wilcoxon rank-sum test. Exclusion of these patients from the main analysis did not alter the interpretation of the findings reported above for the CVICU.