Diagnose und Therapie der Sepsis

Using Arden Syntax Medical Logic Modules to reduce overutilization of laboratory tests for detection of bacterial infections-Success or failure?

OBJECTIVE

Bacterial infections frequently cause prolonged intensive care unit (ICU) stays. Repeated measurements of the procalcitonin (PCT) biomarker are typically used for early detection and follow up of bacterial infections and sepsis, but those PCT measurements are costly. To avoid overutilization, we developed and evaluated a clinical decision support system (CDSS) in Arden Syntax which computes necessary and preventable PCT orders.

METHODS

The CDSS implements a rule set based on the latest PCT value, the time period since this measurement, and the PCT trend scenario. We assessed the CDSS effects on the daily rate of ordered PCT tests within a prospective study having two ON and two OFF phases in a surgical ICU. In addition, we performed interviews with the participating physicians to investigate their experience with the CDSS advice.

RESULTS

Prior to the deployment of the CDSS, 22% of the performed PCT tests were potentially preventable according to the rule set. During the first ON phase the daily rate of ordered PCT tests per patient decreased significantly from 0.807 to 0.662. In subsequent OFF, ON and OFF phases, however, PCT utilization reached again daily rates of 0.733, 0.803, and 0.792, respectively. The interviews demonstrated that the physicians were aware of the problem of PCT overutilization, which they primarily attributed to acute time constraints. The responders assumed that the majority of preventable measurements are indiscriminately ordered for patients during longer ICU stays.

CONCLUSION

We observed an 18% reduction of PCT tests within the first four weeks of CDSS support in the investigated ICU. This reduction may have been influenced by raised awareness of the overutilization problem; the extent of this influence cannot be determined in our study design. No reduction of PCT tests could be observed during the second ON phase. The physician interviews indicated that time critical ICU situations can prevent extensive reflection about the necessity of individual tests. In order to achieve an enduring effect on PCT utilization, we will have to proceed to electronic order entry.

[Guidelines on therapy with blood components and plasma derivatives: human albumin. Recommendations of the scientific advisory board of the Medical Council]

Human albumin (HA) is by far the most expensive option for volume replacement and correction of hypoalbuminemia but is still widely used. The value of HA in the clinical setting continues to be controversial and it remains unclear whether there is still a place for using such a high-priced substance in the present cost-consciousness climate. Thus the Medical Council has presented some recommendations with regard to blood and plasma products including HA. There appear to be no indications for HA to correct hypovolemia either perioperatively or in the intensive care setting including children and patients undergoing cardiac or liver surgery. For maintaining colloid oncotic pressure (COP) cheaper modern synthetic colloids can be alternatively given and the value of HA for correcting hypoalbuminemia is also not clearly justified. Some small uncontrolled studies have shown that only patients with liver cirrhosis, spontaneous bacterial peritonitis and massive ascites drainage may profit from HA. Theoretical benefits such as oxygen radical scavenging or binding of toxic substances are no indications for using HA as beneficial clinical consequences have not yet been demonstrated. Experimental data from cell lines or animals must be viewed with skepticism because they do not mimic the clinical setting. According to the recommendations of the scientific advisory board of the Medical Council the use of HA should be considered very cautiously.

Sepsisähnliches Krankheitsbild bei Immunsuppression nach früherem Mallorcaurlaub

In immunosuppressed patients, a high rate of complications due to opportunistic infection is known. We report the case of a 36 year old patient with ulcerative colitis and a septic complication with ongoing pancytopenia. Due to colonic perforation, colectomy had to be performed. Despite this intervention, the septic constellation persisted. The pancytopenia in peripheral blood counts also persisted with the necessity of repetitive transfusions. A bone marrow biopsy showed an infiltration with Leishmania bodies in macrophages. Tissue culture allowed for typing of the parasites as belonging to the L. donovani/infantum complex, DNA sequencing confirmed infection with L. infantum. This infection must have been contracted during a vacation on Mallorca about 1.5 years earlier. Administration of liposomal amphotericin B cured the patient. Surprisingly, histological examination of the resected colon reveiled the presence of an immunoblastic B-cell lymphoma. In this case, immunosuppression was a prerequisite for the manifestation of leishmaniosis.