A surgeon-specific computer-generated monthly questionnaire was used to improve surveillance of surgical wound infections in outpatients as well as inpatients following discharge. From July 1988 through June 1989, 20,536 surgical procedures were performed at our medical center, of which 53% were for outpatients. The total wound infection rate was 0.63%: 0.13% in outpatients and 1.2% in inpatients (p<.005). Of the infected wounds, 20% were reported by the survey alone and would have gone undetected by conventional surveillance methods (71.4% of outpatient and 13.8% of inpatient wound infections). As a whole, clean and clean-contaminated wounds in outpatients were much less likely to become infected than those in inpatients. Wound cultures were not obtained in 85% of infections reported by the survey alone, and were less likely to be obtained in outpatients. The average time spent by the infection control department on the survey was approximately two hours per week.

To examine rates of falls and injuries by clinical department, a retrospective analysis was performed of 874 inpatient falls during a one-year period in a 1,000-bed acute-care hospital. Incident reports were reviewed, and for those patients injured, medical records were abstracted. Fall rates were calculated by age, sex and service using total patient days as the denominator.

During 1983, 874 falls occurred during 282,713 adult patient days (31/104 days). Fall rates were significantly higher (odds ratio = 2.12; 95% confidence interval [CI]: 1.84, 2.45) in the neuroscience and psychiatry departments (53/104 days) compared with other adult services combined (25/104 days); this difference persisted after direct adjustment for age. Differences by clinical department persisted throughout four additional years of surveillance, although fall rates for the oncology service increased. Injuries following falls occurred among 200 (22.8%) patients.

These data indicate that falls are not random events, and that falls and injury prevention programs can be more appropriately focused by consideration of clinical department.

A cross-sectional serological survey was undertaken in 82 randomly selected high-risk healthcare workers previously vaccinated with the hepatitis B vaccine. The study design allowed for the identification and testing for hepatitis B surface antibody in equal numbers of employees in six-month intervals up to five years after vaccination. The results showed a consistent decline in antibody level with time, and an increasing proportion of participants with antibody levels below the commonly accepted protective level of ≥10 S/N (sample counts/negative control counts) radioimmunoassay units. The percent of vaccinees whose S/N ratio was greater than 10 fell from 10% at one year, to 25% at two years, to over 50% at four years. Based on these figures, as well as the financial costs of hepatitis B in employees and the predictability of booster immunization, it was possible to assess the cost benefit of a hospital policy for reimmunization. At our institution, a strategy of revaccination at fixed intervals could save up to $200,000 over a ten-year period if revaccination was not offered and vaccine efficacy declined. The information obtained should help determine the need for revaccination and the advantages and disadvantages of alternative revaccination strategies.

Forty-three intubated and mechanically ventilated patients in five intensive care units (ICUs) of one hospital developed respiratory colonization or infection with Acinetobacter calcoaceticus subspecies anitratus over a 16-month interval. Neither the frequency nor rate of A anitratus isolation exceeded the hospital endemic norms. Single isolates from 34 of the patients were subtyped by plasmid DNA analysis, two biotyping systems and antimicrobial susceptibility to 24 drugs. Plasmid DNA fingerprints were distinct in 18 isolates (they differed from each other and all others), similar in two and identical or similar in ten. The latter group of isolates were recovered from patients in four ICUs. Reproducibility of biotyping was poor. Neither biotyping nor antimicrobial susceptibility were successful in identifying sameness among the group isolates nor differences among other isolates. We conclude that plasmid DNA fingerprinting should be used to assess the possibility of multiple patient transmissions of the same A anitratus strain in the absence of an obvious outbreak.

Achromobacter xylosoxidans is a nonfermenting, oxidase-positive, gram-negative rod that prefers aqueous environmental reservoirs. A variety of such sources have been implicated in epidemic and sporadic A xylosoxidans infections, including the deionized water of a hemodialysis system, a swimming pool chlorhexidine solutions, intravascular pressure transducers and distilled water. Nuclear medicine tracer material prepared at our institution was implicated in a 1978 outbreak that involved four hospitals. Fourteen patients developed proven or suspected A xylosoxidans bacteremia following intravenous injection with this tracer for lung, liver and bone scans. Contaminated non-bacteriostatic saline used as a diluent for the radioactive material was the likely source.

A xylosoxidans has been isolated from many different body sites, including the bloodstream, urinary tract, central nervous system, peritoneum, respiratory tract, biliary tree; bowel, eyes, ears, pharynx and surgical wounds. Many infected individuals have had compromised host defenses of varying types. Serious infections with this organism may be fatal, perhaps, in part, because of its resistance to multiple antibiotics.

Most intravascular device-related infections are caused by staphylococci, presumably because the microbial flora of the skin surface is the major reservoir of microorganisms colonizing and infecting percutaneously-inserted intravascular cannulas.

Recently, we observed two episodes of group A streptococcal cellulitis and bacteremia related to infection of the subcutaneous tunnel of indwelling catheters. This prompted us to review our experience with nosocomial and community-acquired group A streptococcal bacteremias for the past year, and we identified a third catheter-related case. In our ongoing prospective surveillance of nosocomial bacteremias, we have not previously identified any other cases of intravascular catheter-related bacteremia caused by group A streptococcus. Likewise, in two large prospective studies of Hickman and Broviac catheter-related infections, the investigators did not report infections caused by this organism.