A Case Study on Continuous Infusion of b-Lactam Antibiotics
By Jodi Amendola
Intermittent dosing has long been the most common method to infuse b-lactam cephalosporin and penicillin antibiotics. Intravenous doses are typically given over about 30 minutes, one- to four-times daily, depending on the drug. Continuous infusion therapy, the administration of these antibiotics and other drugs intravenously over an extended period of time, is a recent innovation that reduces drug costs while improving patient outcomes.
Fast becoming the most popular protocol for the provision of these medications in the acute care setting, whether used in concert with antibiotics to fight infection or as preventive drug therapy in the post-operative environment, continuous infusion offers distinct cost saving benefits for medical facilities while simultaneously improving patient outcomes.
A Case Study
Greenbrier Valley Medical Center, located in Ronceverte, West Virginia, is a 122-bed community hospital serving the emergency, surgical, and acute care medical needs of the southeastern region of West Virginia. The Medical Center averages 15 surgeries daily in general; orthopedic; obstetrics and gynecology; and ear, nose, and throat. The hospital is the epitome of a bustling small-town health center and, like its big-city colleagues, it faces a constant struggle to balance costs while maintaining or upgrading quality patient services. In 1995, Greenbrier focused these efforts on improving the outcomes of their intravenous antibiotic program. A review of medical literature showed that some clinicians were experiencing significant cost reductions and improved clinical results by moving intermittent b-lactam regimens to single-drug bolus doses followed by continuous infusions. As part of the effort to improve results and control costs, the Medical Center wanted to alter the way it administered intravenous antibiotics and other drugs. Greenbrier worked with a continuous infusion technology vendor to cut down on infections.
The Medical Center worked with Baxa Corporation (Englewood, Colo), a company that produced products to deal with many aspects of compounding and dispensing fluid medications, including oral unit dosing, IV admixture, syringe infusion, and TPN compounding. One of Baxa's more recent Baxa product innovations is the MicroFuseO Infuser. Designed for intermittent, fixed-rate drug delivery, the syringe infuser provides a simple alternative to proprietary minibag delivery systems and expensive infusion pumps. Specialized infusers offer delivery for niche drugs and 24-hour infusion therapies. Greenbrier began using 72 of the individual Direct Dual Rate Infuser units in 1995 and upgraded more durable and efficient MicroFuse Extended Rate Infuser in early 1999.
Initially, Greenbrier decided to try continuous infusion with cefuroxime for community-acquired pneumonia infections. After developing dosing protocols, the search began for an appropriate infusion pump. A selection committee reviewed the available options. Micro pumps, with dedicated disposables, were not selected due to cost. Similarly, full-size infusion pumps had dedicated disposables and were considered to be too restrictive for patient ambulation. The result of the infusion pump selection process was to purchase 72 Baxa Custom Dual Rate Infusers (DRI).
The DRI unit, less complicated than comparable pumps, allows for the use of low-cost generic syringes and microbore tube sets. The initial custom DRIs were specialized versions of the catalog DRI syringe infuser, with two fixed infusion rates. Rate one was used for bolus infusion over about 20 to 40 minutes. Rate two infused specific syringe sizes and volumes continuously over 24 hours.
In 1999, Greenbrier upgraded their infusers to the new MicroFuseO Extended Rate Infuser (ERI) model.
Controlling the ever-increasing costs of pharmaceuticals and related supplies is a challenge facing not only smaller, rural acute care hospitals like Greenbrier, but also larger hospitals. Tight budgets and labor markets require hospitals to provide more services with less labor. Continuous infusion provided opportunities to reduce drug and supply costs as well. Consequently, Greenbrier was able to cut labor costs by reducing the number of daily doses.
Keeping the required medications on the shelves and maximizing the use of stock and supplies became critical for meeting budget requirements. "With the continuous infuser, we use one $0.25 syringe instead of multiple, $0.90 IV bags," says Michael Barnes, Director of Pharmacy at Greenbrier.
Continuous infusion reduces the number of doses required each day. In turn, this decreases the chance for human error by nurses, technicians, hospital pharmacists, and even physicians. When using the MicroFuse Extended Rate Infusers, only one antibiotic syringe is administered each 24-hour period. This eliminates multiple daily interventions required in intermittent dosing to monitor and replace IV bags. Nurses make one stop at the bedside to load a syringe, returning only if patients require other assistance. With the constant demands during a nursing shift, this results in significant workflow efficiency.
"Continuous infusion concept allow us to prepare medication syringes in advance, saving valuable nurse time and eliminating frequent references to patients' charts," Barnes says. "Furthermore, the infuser has helped our nurses and pharmacy staff to reduce drug waste. Our nurses have more time for direct patient care and essential administrative tasks."
Through continuous infusion therapy, Greenbrier's patients have enjoyed a decreased patient length of stay with lower drug doses. Continuous infusion eliminates the blood level peaks and valleys seen with intermittent dosing. Drug blood levels are maintained consistently above the minimum inhibitory concentration (MIC) required to kill the infection with lower daily doses. Greenbrier has experienced a length-of-stay reduction, averaging a half-day, for its continuous infusion therapy patients.
The compact size and ease of portability of the unit makes handling easy. As long as the physician agrees, and the medical condition does not warrant against it, the MicroFuse Infuser can be detached from the IV pole mount or hanger and placed in a specially designed "waist pack," which can be worn by the patient. This new mobility frees patients to satisfy their own bathroom needs, move easily throughout the hospital for ancillary tests, or attend physical therapy sessions without the unwieldy pole apparatus that often tethers them to their beds or hospital rooms.
Previously, Greenbrier suffered extensive malfunctions and equipment breakdowns because of incidental damage due to patient product mishandling. By working with nurses at Greenbrier, Baxa developed a more durable unit, limiting the number and severity of repairs, and extending the service life of the infuser. The complete upgrade to the new model - the MicroFuse Extended Rate Infuser - was completed in early 1999.
"The original model did not withstand the rigors of a fall to the floor," Barnes says. "We often had large numbers of units out of service for repairs."
Jodi Amendola is the regional VP, CPR Communications for Baxa Corporation (Englewood, Colo).