November 3, 2011

Trauma program’s infection-fighting efforts show results

Addison May, M.D.

Trauma program’s infection-fighting efforts show results

A new antibiotic stewardship protocol resulted in a significant decrease in resistant health care-acquired infections in Vanderbilt University Hospital’s trauma and surgical intensive care units.

The findings of a 10-year study of infection reduction strategies provide justification for widespread implementation of antibiotic stewardship tactics as part of infection reduction campaigns.

The study, conducted within Vanderbilt’s Trauma Intensive Care Unit (TICU) and Surgical Intensive Care Unit (SICU), proved a greater than 75 percent reduction of multi-drug resistant pathogens and an equal increase in pathogens pan-sensitive to all classes of drugs.

“General pathogen resistance has been increasing steadily over time in hospitals globally, particularly in intensive care units,” said Addison May, M.D., director of Surgical Critical Care and senior author of the study.

Addison May, M.D.

Addison May, M.D.

Marcus Dortch, Pharm.D.

Marcus Dortch, Pharm.D.

“People tend to take a nihilistic approach to limiting pathogen resistance because it’s so hard to believe you can change that. However, our results over the last 10 years of this study clearly indicate you can dramatically alter (pathogen resistance) in your ICU.”

Critically ill patients are more susceptible to infections, making prompt administration of broad-spectrum empiric antibiotics a commonly used strategy to improve outcomes of patients at risk for sepsis.

However, overuse of antibiotics leads to pathogen resistance and thus, subsequent infections, explained Marcus Dortch, Pharm.D., clinical pharmacist of Surgical Critical Care and lead author of the study.

Recognizing this issue, May, Dortch and colleagues established an antibiotic stewardship program in 2002 within the TICU and SICU that included strict indications for antibiotics, limited treatment courses and an antibiotic rotation to try to limit the potential impact of multi-drug resistant infections.

After developing a process to track the pathogens and their resistance patterns over time, they designed protocols that provided precise medication schedules as a systematic process for providers to follow for all patients.

The protocols made antibiotic use indication-specific and was designed to cover the pathogens most common in each area.

A schedule was implemented to change the antibiotic given for each quarter, helping prevent “selective pressures,” or using the same antibiotic every time.

“Use of order sets and making antibiotic use more consistent across the board helped us maintain compliance with the new schedule protocol,” Dortch said.

Additionally, the units became more aggressive in seeking empirical evidence of infections to ensure antibiotics are properly prescribed and not overused.

“Roughly 80 percent of critically ill patients present symptoms of systemic inflammatory response, including fever, elevated white count and increased respiratory rate. But only about 20 percent of those patients actually have an infection,” May said.

“Reducing the over-diagnosis of infections by requiring more precise diagnostic techniques helped to reduce our antibiotic exposure significantly.”

May and Dortch worked with Thomas Talbot, M.D., MPH, Chief Hospital Epidemiologist; Rondi Kauffmann, M.D., surgical resident; Sloan Fleming, Pharm.D., former trauma clinical pharmacist; and Lesly Dossett, M.D., MPH, former chief resident at Vanderbilt to conduct this study, which recently published in Surgical Infections.

Because the TICU and SICU are no longer seeing the same resistance patterns as were found prior to the antibiotic stewardship program, the researchers will next examine the current antibiotics used to see if they can be reduced to more narrow-spectrum, less toxic and less expensive medications.

Although not measured in their study, the study authors also credit institution-wide initiatives such as the hand hygiene campaign and the “VAP bundle” — evidence-based practices that, when implemented together, result in dramatic reductions in ventilator associated pneumonia – for the reduction of total infections.