Susceptibility and minimum inhibitory concentration are twoessential guideposts for clinicians in their selection of properantibiotic therapy. The lab and pharmacy in our 212-bed hospital haveadded a third–cost effectiveness. We furnish relative cost data for different drugs clinicians mayprescribe. This information, indicating how many times more expensiveone drug is than another, accompanies each report of culturesusceptibilities and minimum inhibitory concentrations.
Clinicians alsocan look up the exact dollar cost of planned antibiotic therapy oncharts widely posted throughout the hospital. Some costly drugs have virtually disappeared from use as a result.Of course, our clinicians first had to be shown that cheaper antibioticswere just as effective. As recently as six years ago, when I completed my medicaltechnology training, the listing of antibiotics available for clinicaluse was relatively simple.
I had learned drugs of choice for specificinfections, and setting up gram negative and gram positive batteries forsusceptibility testing did not require lengthy consideration. Since then, new antibiotics have cascaded like Niagara Falls intothe marketplace. Each of these many products promises a great deal.Pharmaceutical companies tell physicians about clinical effectiveness,indications and contraindications, possible adverse reactions, andmethods of administration and dosage. But the companies and detailpersons gloss over one critical point–R&d and other factorscontinually build up the prices of new drugs, threatening higher coststo patients in a period of already skyrocketing medical expenses.
Located in an area where many senior citizens live, our hospitalhas a large percentage of Medicare admissions. The transition toprospective payment makes it imperative that antibiotic therapyaccomplish its purpose and be cost-effective at the same time. Toprescribe wisely, clinicians need cost data as well as the otherinformation about drugs. An opportunity to present such data on an ongoing basis came inFebruary 1983. The laboratory acquired an automated instrument thatperformed bacterial identification and four-hour susceptibility testing.We had to develop a new report form, and that was the vehicle thelaboratory and pharmacy had been waiting for. The clinical pharmacist devised a cost code based on the contractprices of each drug we carried (Figure I).
The code is relative,assigning a “1” to the least expensive antibiotic andmultiples of its cost to more expensive drugs. For example, treatmentwith oral ampicillin is listed as 1, while piperacillin is marked 52.That means piperacillin is 52 times more expensive to use than oralampicillin. As chief microbiologist, 1 designed a report form that wouldincorporate the cost code with susceptibility and MIC data. By May, theform had been approved by the infection control committee, presented tothe medical staff, printed, and put into use. Clinicians noticed the new information on the form and commented onit, but did not follow through as we had hoped. Since the code wasrelative, they did not perceive the actual dollar impact of switching tolower cost drugs. Clearly, something more was needed to get the messageacross.
The pharmacist next drew up a chart of comparative hospital costsfor 10 days of intravenous therapy with equivalent doses of commonlyused antibiotics. Copies in a hard-to-miss 14 X 8-1/2-inch size wereposted in the doctors’ lounges and all the dictating booths inmedical and surgical units. The sample in Figure II displays costs forclasses of drugs, but the chart that clinicians referred to had thenames of the antibiotics. The span of treatment costs was predictably wide. Penicillins ranged from a low of $24 for 10 days of I.
V. therapy to a high of $568,for example. Now a number of clinicians began prescribing with bothsusceptibilities and cost-effectiveness in mind. Others remainedskeptical, however. A typical comment from the holdouts:”Gentamicin may in fact be cheaper, but more organisms aresusceptible to tobramycin.” So, to make our case airtight, we distributed one final set offigures–susceptibility percentages for our institution (Figure III).These proved that lower-cost antibiotics were often at least aseffective as much more expensive drugs, and even when they weren’t,the difference was not significant. Grop D Streptococcus, for example, is 96.
2 per cent susceptible toa new broad spectrum penicillin and 92.5 per cent susceptible to anolder form of penicillin. But 10-day I.V. therapy with the boradspectrum penicillin carries the $568 cost that we noted above, whilecomparable treatment with the other penicillin costs only $24. Among theaminoglycosides, one drug registered slightly higher susceptibilitypercentages among some organisms than products costing six and 12 timesas much. The joint laboratory-pharmacy cost awareness program has takenhold, although optimum drug prescribing is still a goal rather than areality.
One particularly encouraging set of statistics involves use ofa costly third-generation cephalosporin. In May 1983, ourhospital’s clinicians ordered more than 1,300 doses of thisantibiotics; in May 1984, they ordered none. It is still prescribed forpatients from time to time, but not very often. Other efforts to improve prescribing include discussions withindividual clinicians and periodic reviews at medical staff meetings.We haven’t felt a need to monitor physicians’ ordering habits.
Pharmaceutical companies know about our program. This may beleading to more careful sales presentations at our hospital. In summary, our laboratory-pharmacy partnership fulfills aresponsibility for helping the clinician prescribe cost-effective andfirst-rate therapy.
It’s one small facet of the hospitalwidecooperation made more necessary than ever by prospective payment.