CHLORHEXIDINE GLUCONATE IN THE ICU
According to this study:
* Cleaning patients'skin with chlorhexidine gluconate lowers the rate of VRE colonization.
* The practice also reduces environmental contamination with VRE.
Researchers at a large Chicago medical center found that bathing patients in the medical ICU (MICU) with a disposable cloth saturated with 2% chlorhexidine gluconate significantly reduced the rates of contamination of patients' skin and the ICU environment at large with vancomycin-resistant enterococci (VRE), a common nosocomial pathogen.
In a study involving 1,787 patients, the use of chlorhexidine gluconate was compared with two other bathing modalities, common soap and water and disposable unmedicated cloths, to determine whether use of the disinfectant affects the colonization of VRE on patients' skin, as well as related environmental contamination. Patients' rectums were swabbed upon admission to the MICU if the patients were expected to remain there for more than three days. If the initial culture was negative for VRE, rectal cultures were again obtained every one to two days and, if positive, a further evaluation for colonization was performed and culturing from the patient's skin (in the inguinal and antecubital areas), from the health care provider's hands, from objects in the room, and from the external ICU environment was completed. Each bathing technique was evaluated separately during three successive periods of time.
The number of patient-days and patient characteristics did not vary significantly among the three groups. Eighty-six patients in the total sample were identified as having VRE colonization, and the researchers found that after bathing them with the chlorhexidine cloths, there was a 2.5 log10 count reduction in VRE colonies on the skin, as compared with the soap and water, a reduction that persisted after possible confounding variables such as the administration of antimicrobial agents, the time of acquisition of the culture specimen, and the presence of catheters or drains were controlled for.
The analysis also revealed that environmental objects and the health care provider's hands were less contaminated after the use of chlorhexidine, which likewise reduced the incidence of the spread of VRE to patients with negative cultures to a rate of nine per 1,000 patient-days, compared with 26 in the soap-and-water group and 15 in the unmedicated cloth group. Two possible pitfalls of the intervention, the risk of skin irritation and microbial resistance to chlorhexidine, were not found to be significant.
The study findings support the use of chlorhexidine gluconate baths to assist in lowering the rates of VRE colonization in ICU patients and of contamination of environmental surfaces and health care workers' hands with the bacteria, leading to less frequent acquisition of infection. The cost of implementing the practice was not addressed in the study; however, provided that the use of chlorhexidine can accomplish enhanced control of VRE at the source, it might yield significant cost savings in the long term. -AK
Vernon MO, et al. Arch Intern Med 2006;(3)166:306-12.
GATIFLOXACIN AND GLUCOSE ABNORMALITIES
According to this study:
* The fluoroquinolone has been associated with both hypoglycemia and hyperglycemia.
* Clinicians might do well to consider not prescribing gatifloxacin altogether.
Limited data have suggested that gatifloxacin, one of the broad-spectrum antibiotics of the fluoroquinolone class, the most widely prescribed in the United States, might increase the risks of hypoglycemia and hyperglycemia. To investigate that association, researchers examined the medical records of approximately 1.4 million residents of Canada 66 years of age or older.
A population-based, case-control study conducted during a period of two years involved patients who received hospital care for hypoglycemia, hyperglycemia, diabetic ketoacidosis, or hyperosmolar nonketotic coma within 30 days of receiving a prescription for a macrolide antibiotic, an oral second-generation cephalosporin, or a respiratory fluoroquinolone (gatifloxacin, levofloxacin, moxifloxacin, or ciprofloxacin). For each patient, as many as five controls were randomly selected from among those who had received antibiotics but not hospital care for one of the aforementioned conditions and matched according to age, sex, and the presence or absence of diabetes.
A total of 788 patients, 93.4% of whom were matched to five controls, received hospital care for hypoglycemia within 30 days of the initiation of antibiotic treatment (at a median interval of six days). Ninety-one percent of case patients were being treated for diabetes. Patients treated for hypoglycemia were 4.3 times more likely than controls to have been treated with gatifloxacin rather than a macrolide antibiotic, and 1.5 times more likely than controls to have been treated with levofloxacin. No greater risk of hypoglycemia after treatment with moxifloxacin, ciprofloxacin, or second-generation cephalosporins was found.
The researchers also identified 470 patients (94.9% of whom were matched to five controls) treated for hyperglycemia-related conditions at a median interval of five days after the initiation of antibiotic treatment (only 37.9% were receiving treatment for diabetes). Patients treated for hyperglycemia were 16.7 times more likely than controls to have been treated with gatifloxacin rather than a macrolide antibiotic. No greater risk of hyperglycemia was associated with any other respiratory fluoroquinolone or with second-generation cephalosporins.
The researchers recommend that prescribers and pharmacists be aware of the greater risk of possibly life-threatening glucose abnormalities associated with the use of the gatifloxacin and that they instruct patients to seek medical attention if symptoms of hypoglycemia or hyperglycemia develop. They suggest that clinicians might want to avoid prescribing gatifloxacin altogether because it doesn't offer significant advantages over other antibiotics that haven't been associated with glucose abnormalities.-SDSJ
Park-Wyllie LY, et al. N Engl J Med 2006;354(13):1352-61.
NURSES' UNDERSTANDING OF PULSE OXIMETRY
According to this study:
* Critical care nurses have a sufficient level of knowledge concerning pulse oximetry.
* The nurses also have a good understanding of its limitations as an assessment tool.
Nurses working in critical care settings often provide care to patients who need continuous pulse oximetry monitoring. Because knowledge of the principles of pulse oximetry is necessary for proper monitoring, a study was conducted to measure how well-versed critical care nurses are in the use and interpretation of the technology. The results showed that not only did the nurses have a clear understanding of pulse oximetry principles, they knew more about the technology than other clinical workers have in earlier studies.
The sample consisted of 551 critical care nurses attending a 2002 American Association of Critical-Care Nurses conference, each of whom participated completely voluntarily and received a $5 phone card after completing a 10-minute written survey evaluating knowledge of pulse oximetry and the participant's perceptions of its performance in her facility. The questions focused on the factors that can affect the readings, the type of monitoring device on the participant's unit, and the necessity of obtaining arterial blood gas measurements. Demographic information was also collected.
The mean age of the participants was 44 years; they had a mean of 20 years of nursing experience, 15 of which had been spent in critical care. Nearly half (48%) held baccalaureates, 20% held master's degrees, and 31% held an associate's degree or a diploma. Approximately 45% were certified in critical care, and the majority (68%) worked in community hospitals.
Seventy percent of the sample knew whether the pulse oximetry monitoring devices on their units were tolerant of motion. In the identification of the factors that can adversely affect the accuracy of pulse oximetry readings, 63% proved to be aware of those related to movement of the patient (shivering, for example), 86.5% demonstrated awareness of the significance of poor peripheral perfusion, and 86.5% were cognizant of the significance of poor signal quality. Thirty percent of the nurses believed (incorrectly) that pulse oximetry could replace arterial blood gas measurements in critically ill patients if the reading is greater than 90%.
The study findings indicate a sufficient level of knowledge of the operations involved in pulse oximetry and the interpretation of the readings among the sample group of critical care nurses surveyed. However, the results were generated from a sample of nurses attending a critical care conference and may not be representative of all critical care nurses. -AK
Guiliano KK, Liu LM. Dimens Crit Care Nurs 2006;25(1):44-9.