1. Kayyali, Andrea MSN, RN

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PDAs might serve as a cost-effective means of surveillance.

In a recent study, researchers who assessed the joint use of handheld personal digital assistants (PDAs) and surveillance by computer in the identification of nosocomial urinary tract infection (UTI) in a critical care population found it to be nearly as accurate, less time-consuming, and less costly than observation by an infection control practitioner (ICP).


The researchers selected patients who had had a urinary catheter in place for more than 48 hours and were in the medical intensive care unit (MICU) for at least that long, excluding from the evaluation those who had a urine culture positive for UTI within the first 48 hours of admission. Data were collected independently over the course of one month by an ICP (the traditional approach) and by a research assistant using a PDA and a computer (the technologic approach). The ICP performed daily rounds among the eligible MICU patients, identifying clinical indicators of UTI such as duration of catheter placement, urine culture results, diagnoses, and symptomatology. The ICP continued to monitor patients for seven days after the removal of catheters, and all data were entered manually into a database. In the technologic approach, the gathering of data entailed first uploading the MICU patient census into the PDA, then downloading it from there into a database. A research assistant obtained the number of days of catheter placement from the patient's bedside chart and entered it into the PDA and then downloaded it into the database. By daily automatic query, the password-secured database extracted microbiology reports of all positive urine cultures in the group of eligible patients.


The ICP approach identified eight cases of nosocomial UTI during the study period, three of which were considered to be attributable to urinary catheter placement. The remaining five cases were excluded because the diagnoses were made within 48 hours of the patient's admission to the MICU. Comparatively, the PDA approach also identified the eight patients with UTI and correctly excluded the five who did not meet the established criteria. The ICP, however, was able to correctly specify the unit on which the infection originated, whereas the PDA inaccurately associated two of the three infections with units outside the MICU because of errors in programming.


The researchers note that the joint use of the PDA and computer saved approximately 6.5 hours per week in time spent collecting and evaluating data, compared with ICP surveillance, and that, although such use would entail a considerable initial financial investment, hospitals could realize significant savings by the fourth year, especially if the practice were implemented on several units. In addition, they note that the study was limited in scope by a short time period during which no patients were diagnosed purely according to clinical symptoms-had some such cases been included, the PDA and computer surveillance method may have proven to be less accurate than the findings indicate.


Farley JE, et al. Am J Infect Control 2005;33(8):444-9.



Investigative study challenges propriety of routine use.

Researchers in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial, found that the use of pulmonary artery catheters (PACs) in critical care patients did not improve overall mortality and led to a greater number of adverse events, eliciting the conclusion that they should not be used routinely to guide the treatment of patients with advanced heart failure.


The ESCAPE trial was a large, randomized, controlled study conducted over a period of nearly three years in 26 institutions in North America, into which 433 patients diagnosed with advanced and symptomatic heart failure were recruited. Upon enrollment, the patients were randomly divided into two groups, one in which clinical judgment alone served as the basis for treatment decisions, and another in which clinical judgment and also PACs were used for that purpose. The goal of therapy in both study arms was improvement in the signs and symptoms of congestion, and in the PAC group the attainment of certain hemodynamic parameters was also sought. The researchers didn't determine the medications or therapies used, but strongly discouraged the use of inotropes in favor of diuretic and vasodilator therapies.


The trial's primary end point was the number of days the patient survived out of the hospital during the first six months after enrollment. In that measure, there was no difference between the PAC group and the control group, and neither were there differences in mortality rate or the duration of hospitalization. Secondary end points of the study included the quality of life and physiologic measures, in regard to which there were improvements in both groups, although more substantially in the PAC group. Specifically, at three measurement time points, PAC patients scored better on a "time trade-off" questionnaire designed to ascertain the amount of survival time a patient would exchange for a higher quality of life.


The study revealed also a greater number of adverse events in the PAC group, the majority of them attributable to catheter infection, a finding that was cited as one reason that the trial recruitment was stopped prematurely.


Because decreased congestion that reduced symptoms was attained in both groups, and there was no difference in the primary end point between them, the researchers conclude that the use of the PAC is not routinely necessary to guide treatment of advanced heart failure, especially in light of the greater risk of adverse events. It may be considered, however, in patients with advanced heart failure when traditional therapies have proven ineffective and the information obtained is to be used for the purpose of making treatment decisions.


Binanay C, et al. JAMA 2005;294(13):1625-33.



Might lower surgical site infection rates without incurring great risk.

In a recent editorial, a physician advocates the administration of a higher oxygen concentration in surgical patients to help reduce surgical site infection rates, in an argument based on current and previous research conducted on the topic, although all such studies did not reach the same conclusion regarding the possible benefit conferred in the practice.


The author examined the findings of three research trials, the most recent one a study published in 2005 involving patients undergoing colorectal surgery in which the researchers found that in those who received intraoperative 80% fraction of inspired oxygen (FIO2) (n = 148) rather than 30% FIO2 (n = 143) there was a 39% lesser risk of the development of surgical site infection. In a study published in 2000, a randomized trial of 500 patients also undergoing colorectal surgery, there were comparable results-a surgical site infection rate of 5.2% in the group given 80% FIO2 (n = 250), and a rate of 11.2% in the group given 30% FIO2 (n = 250). However, a study published in 2004 yielded markedly different results-in a randomized, controlled trial in which FIO2 concentrations of 80% in one group and 35% in another were used, the surgical site infection rate was 25% and 11%, respectively. One of the differences in that study that might partially account for the discrepant findings is the performance of a variety of abdominal procedures, not only colorectal surgery.


The author cites also various studies of the physiology of oxygen tension in the tissues (partial pressure of oxygen [PO2]) and how it can support resistance to infection, some of the theories advanced therein proposing that it might enhance the bactericidal property of leukocytes, providing a sound biological rationale for the effectiveness of the practice in stemming proliferation of such microorganisms at the surgical site.


The author asserts that, because the administration of a higher concentration of FIO2 during surgery poses little risk and has been proven effective in two independent trials, the practice is supportable despite the lack of unanimous agreement concerning it and recommends that the surgical team strive to reduce surgical infection rates also by using established preventive methods, such as the administration of the right antibiotic at the right time, the maintenance of normal glucose levels, and the clipping (rather than shaving) of hair in surgical preparation.


Belda FJ, et al. JAMA 2005;294(16):2035-42; Greif R, et al. N Engl J Med 2000;342(3):161-7; Pryor KO, et al. JAMA 2004;291(1):79-87.