Quantitative Analysis

Quantitative analysis: analyze care delivery to identify the rate-limiting steps 

Ultimately patients and providers care most about final clinical outcomes, like whether or not a patient has developed a hospital-acquired DVT or PE. Our chances to reduce the likelihood of hospital-acquired VTE begin the moment the patient is admitted and actually recur every day. To help the team focus its time on the most high yield interventions, it is extremely helpful to identify the most frequent sources of missed chances to prevent HA-VTE. Through the eyes of a perfectionist, these missed chances can be thought of as “rate-limiting steps.” To someone who is merely an optimist, they may be thought of as “high leverage points” for improvement.

Empirical analysis of each step below is very useful. We highly recommend the following brief audit exercise. Go to 20-30 random charts on the pilot unit. Tally up the prevalence of appropriate prophylaxis (as judged by the team’s new gold standard, the VTE protocol). Next, look at the charts of the patients who were not on appropriate prophylaxis. If mechanical prophylaxis alone has been ordered, look also at the patient to determine if mechanical prophylaxis is being worn. This should take no more than 2-3 hours, especially with a chart audit form. Once the chart audit is complete make a simple tally sheet of the type and number of failures; or alternatively annotate the diagram as below.

Figure 2-2: Care Delivery for Preventing Hospital-Acquired VTE. In this hospital, a sample of 25 charts showed that two-thirds of failures to order appropriate VTE prophylaxis occurred at the time of admission and are attributable either to provider ordering or medical decision-making (35% ordered nothing for VTE prophylaxis, another 30% ordered something that the VTE team considered inappropriate). One in 5 failures was due to failures to re-assess VTE risk later in the hospital stay. One in 8 failures was due to problems with delivering or wearing sequential compression devices.

With quantitative information like this the improvement team can make rational choices when deciding which steps in care delivery to re-design and which steps to measure. For VTE prevention in the hospital above, a key moment occurs when physicians write admission orders. At this moment at least two different types of failure modes appear to contribute significantly to a poor overall baseline prevalence of appropriate VTE prophylaxis.