|Articles|September 15, 2017

Mystery Patient Drills Reveal Gaps in Infection Control Practices in NYC Hospitals

New CDC Morbidity and Mortality Report highlights gaps in infection control practices in many New York City hospitals.

Rapid detection and isolation of patients with severe and highly contagious infectious diseases is paramount in the hospital setting. To this end, many institutions carry out “unannounced mystery patient drills” in an attempt to assess infection control practices that are currently in place to identify areas of improvement. Ninety-five of these drills were carried out in 49 New York City hospital emergency departments (EDs) between December 2015 and May 2016. The findings, published in the latest Centers for Disease Control and Prevention (CDC) Morbidity and Mortality Report highlight gaps in infection control practices in many New York City hospitals.

These drills marked the “first report describing the use of unannounced mystery patient drills to test ED preparedness for Middle East Respiratory Syndrome (MERS) and measles,” according to the report. Mirroring current outbreak scenarios, patients presented to EDs with signs and symptoms, and appropriate travel history, consistent with either possible measles (53 drills) or MERS (42 drills). Emergency department teams were evaluated on “key infection control performance measures, including time to patient masking and isolation,” according to the report. Drills were considered to have failed, and were thus terminated, if the ED failed to triage the patient within 30 minutes.

In total, 80% of the patients were asked if they had experienced a recent fever, and 85% were asked about recent travel. Half of the patients were asked about any rashes or unusual skin lesions, and 68% were asked about any respiratory symptoms. A total of 88% of the patients were given a mask, “including 45 (85%) patients in the measles scenarios and 39 (93%) patients in the MERS scenarios,” according to the report.

An assessment of the “times required to perform patient masking and isolation,” revealed a median time of 1.5 minutes (range of 0 to 47 minutes) from the time a patient entered the hospital to when they were masked, and a median time of 8.5 minutes (range of 0 to 57 minutes) before they were isolated. In addition, “masking and isolation occurred significantly more frequently when travel history was obtained (88%) than when it was not (21%).” Variability was seen between hospitals in “their ability to identify potentially infectious patients and implement recommended infection control measures in a timely manner.”

In all, 74 (78%) of the hospitals passed the drills, and no significant differences were found between masking for MERS vs measles patients. However, 19 (39%) of the hospitals “failed at least 1 drill,” which is concerning given the highly infectious nature of these diseases, and high transmissibility of these diseases in ED waiting areas. The researchers note that “masking and isolation occurred significantly more frequently in situations where a travel history had been elicited. [This] suggests that routinely inquiring about recent travel could prevent exposures to infectious patients at critical entry points to the health care system.”

Aside from the masking and isolation procedures, evaluators also recorded adherence to “key infection control practices,” and found that many EDs needed to make changes in this area. In total, 36% of the hospitals practiced appropriate hand hygiene, 74% practiced appropriate PPE use, and 70% practiced appropriate posting of isolation signage. These results indicate that all hospitals could potentially benefit from “routing competency-based infection-control training programs,” according to the report.

Two limitations of the drills highlighted in the report include the fact that, “exercise evaluation was limited to items that were under direct control of the staff members who participated in the drill, the controller, and the evaluator,” and that “controllers were not able to objectively present all signs of illness (eg, fever, chills), and the moulage used to simulate a measles rash might have been misleading or unconvincing, although this information was not captured in the drill reports.”

As a result of this report, researchers have created a toolkit which can be used in other jurisdictions “to support health care facilities and health departments conduct similar drills to identify areas for improvement and enhance readiness at a critical point of entry into the health care system.” The toolkit is available at http://on.nyc.gov/IDPrep.


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