Practice Guidelines Reduce Unnecessary Testing in the CCU

Abstract & Commentary

Synopsis: A 3-part intervention (guideline development, computerized order templates, and education) led to an overall 17% reduction in test ordering without a change in clinical outcomes.

Source: Wang TJ, et al. A utilization management intervention to reduce unnecessary testing in the coronary care unit. Arch Intern Med. 2002;1652: 1885-1890.

The routine use of laboratory and radiologic testing has come under increased scrutiny in recent years as a consequence of studies that suggest substantial variation in testing practice with comparable outcomes. While many studies have examined interventions to reduce test ordering, few have been conducted in the ICU, and none were found that targeted coronary care unit (CCU) patients. The study examined outcomes following an intervention designed to reduce test use in 471 patients admitted to a 15-bed CCU over a 6-month period in a large (855 bed) academic teaching hospital.

A multidisciplinary team (cardiologists, internist, medical intensivist, CCU nurses) developed guidelines using evidence-based recommendations when possible and expert opinion otherwise. The guidelines were incorporated into the CCU’s computer order entry template and presented to the house staff and nursing staff by the CCU director and a cardiology fellow. House staff were encouraged, but not required, to use the guidelines. Outcomes during the 3-month intervention period (n = 225 patients) were compared with the same 3-month period during the prior year (n = 246 patients).

No significant differences were seen in patient demographics or severity of illness between the 2 periods. During the intervention period, significant reductions were noted in the ordering of all chemistry tests, with the largest ordering reductions occurring in calcium, magnesium, and phosphorus ordering (40%, 31%, and 40%, respectively). Reductions in the ordering of other tests ranged from 7% for serum chloride to 23% for serum potassium. Nonsignificant reductions were seen in the ordering of complete blood counts (P = 0.34), arterial blood gases ([ABGs], P = 0.07), and chest radiographs (P = 0.10). When all tests were considered together, the estimated reduction was 17% (P < 0.001). There were no significant differences in hospital mortality, readmission to the CCU or hospital, or days of ventilator support between the 2 groups.

Comment by Leslie A. Hoffman, Phd, RN

The basic concept underlying the use of guidelines or protocols is that routine patient management can be improved when interdisciplinary teams of clinicians use evidence-based protocols to complement their clinical judgment. In the critical care setting, patients are likely to receive a large panel of "routine" daily tests based on the assumption that they will benefit from this increased surveillance. This study examined the potential to reduce such testing through evidence-based guidelines that provided specific recommendations for when routine testing was indicated and when this testing could be eliminated.

The intervention was associated with an overall reduction in test ordering. Importantly, this reduction was not associated with a measurable change in clinical outcomes. The intervention developed by the research team was designed using a behavioral model that suggests that such interventions will be most effective if they target attitudes or knowledge (predisposing factors), reduce barriers (enabling factors), and include periodic reinforcement for all involved participants (reinforcing factors). The educational sessions targeted both the house staff and the nursing staff since, unlike the house staff, the nursing staff does not change substantially from month to month. Therefore, the nursing staff could assist in promoting use of the guidelines by questioning orders that were not consistent with recommended practice.

The study was most effective in reducing orders for chemistries. In contrast to expectations, ordering of ABGs was only modestly affected. The research team attributed this finding to the widespread (and difficult to modify) perception that every change in ventilator settings needed to be accompanied by an ABG determination.

In the critical care setting, research involving the testing of protocols has yielded several important advances, as documented by randomized, controlled clinical trials. Of these, the most notable is the consistent support of positive outcomes when protocols are used to identify patients ready to wean from mechanical ventilation. Other examples include the reduction in mortality seen when protocols were used to achieve a lung-protective ventilatory strategy and positive outcomes when protocols are used to guide the provision of nutritional support, maintain tight glycemic control, and titrate the use of sedation and analgesia. Findings of this study support the need for continued examination of all aspects of critical care practice with the goal of identifying the approach most likely to be of benefit and eliminating practices based on tradition that have no demonstrated value.

Dr. Hoffman is Professor Medical-Surgical Nursing Chair, Department of Acute/Tertiary Care University of Pittsburgh School of Nursing.