The postoperative wound infection experience in 11 Israeli hospitals was investigated with two objectives: (1) to utilize the variability among hospitals for a better understanding of the determinants of these infections, and (2) to present surgeons and infection control teams with information upon which they can take action. This article summarizes the methods that were applied to maximize the uniformity of information obtained from hospitals. (1) The same kind of patients were sampled in every hospital. (2) The data collection system was standardized, and analyzed for errors. The overall error rate was small (2%) but there were potential problem areas, such as missing information on underlying diagnoses (12%). Few errors (1%) were found in the nurses' observations of the wounds. (3) All wound infections were diagnosed in a uniform manner by convening a panel of four specialists at the central Israeli Study of Surgical Infections (ISSI) office. (4) The definition of infection that was finally chosen for this multicenter study had to be broadened to include, in addition to pus, “discharge other than pus,” because of the higher reliability among panel members. This definition was also clinically valid in terms of morbidity. (5) The rate of postdischarge infections was estimated and was not found to be related to the discharge policies in the various hospitals.

In a study of 5,571 patients from the general surgery departments of 11 Israeli hospitals, the crude overall wound infection rates showed interhospital heterogeneity. The rates ranged from 6.3% to 12.4% (P(X2) = 0.039). Controlling for the different distributions of procedures performed in the various institutions did not reduce this variability. None of the hospitals had either consistently high or consistently low infection rates. A hospital could have low rates for one procedure and high rates for another. Therefore, the decision was made to proceed with procedure-specific analyses. This article details results of the analysis of 1,487 hernia operations. Four variables (old age, infection at another site, incarceration, and introduction of drains) accounted for almost all the differences in infection rates among the institutions. Of the four, presence of drains had the strongest association with infection (P derived from the logistic model <0.001). The risk was consistent in all hospitals and was unconfounded by other measurable factors. In contrast, the pattern of using drains seemed arbitrary and inconsistent, ranging from 9% of patients in one hospital to 41% in another. These findings were used as a basis for discussion with the surgical teams and for the initiation of a randomized clinical trial on the use of drains in hernia operations.

We initiated a prospective study of penile prosthesis implant surgery to evaluate risk factors for infection and other complications. Twenty-one patients admitted for surgery or related complications were evaluated over a seven-month period. The two types of penile prostheses implanted were (1) inflatable and (2) semirigid. Nine of 21 patients (43%) developed postoperative complications. Although cephapirin and gentamicin were given prophylactically, four of nine patients had four wound infections and one case of pneumonia. One case of Bacteroides fragilis bacteremia was due to stool incontinency during surgery. In two of the wound infections, removal and reinsertion of the prosthesis was necessary. Other complications included hypotension during surgery, prosthesis malfunction and malposition, and urethral tears. There were no significant associations between infection and age, length of surgery, or type of prosthesis used. These complications contributed to prolonged hospital stay and readmission (87 extra days for the infected patients at a cost of $44,000). Antibiotic costs to treat the infections totaled $1,900. Prospective evaluation by infection control practitioners of various elective surgeries can be useful in quantitating the complication rate and targeting patients at risk, with the goal of minimizing hospital costs.

During an eight-month period, 25 hospitalized patients became infected or colonized with methicillin-resistant Staphylococcus aureus (MRSA) in a 464-bed acute care, medical-surgical teaching hospital. There were only five cases during the eight months prior to the outbreak period (P < 0.0001). Initial measures, including category-specific isolation and education, did not limit the spread of the outbreak of a strain of MRSA. This prompted institution of additional measures including (1) strict isolation of all infected and colonized cases; (2) prospective microbiological surveillance to detect additional cases; (3) multiple site cultures of identified cases to determine the extent of colonization; (4) employee and environment surveillance; (5) antibiotic decolonization of patients and employees; and (6) educational efforts. The highest number of personnel carriers were noted in one of the critical care units where most of the cases occurred. The decolonization protocol was 100% effective for personnel carriers. The incidence of nosocomial cases of MRSA fell to zero in the five months following the implementation of the strategy. The cost of the entire eradication process was approximately half that of treating a single MRSA bacteremia.

Methicillin-resistant Staphylococcus aureus (MKSA) infections have become a major problem in many US hospitals in the last ten years.‘,’ Attempts to solve the problem have been hampered by many factors. One of these factors is the difficulty in eradicating the organism from colonized sites and thereby removing one of the reservoirs of endemicity. Another complicating factor is the lack of consistency in the published literature regarding what constitutes eradication and, therefore, when it is appropriate to discontinue isolation of patients or work restrictions of personnel. Even the decisions regarding when and how often to culture personnel remain difficult to define.” Finally, although the Australian experience illustrated an environmental component to an MRSA outbreak, the role of the environment in MRSA infections remains unclear. The following report describes the measures utilized to eradicate low-level MRSA skin colonization in a long-term psychiatric patient and illustrates several problems of-long-term MRSA carriage in institutionalized patients.

Recent concerns about the clinical relevance of susceptibility testing echo those expressed previously by a number of authors.’-” These concerns are well founded and are perhaps even more important today because of the proliferation of new antibiotics and the changes in reimbursement philosophy.” Ultimately, the question becomes that raised by David Greenwood: “In vitro veritas?” The following discussion will review the role of susceptibility testing in clinical medicine with emphasis on myth versus reality. In addition, new directions for susceptibility testing that promise increased clinical relevance will be covered.

This is the second in a series of articles addressing legal issues in infection control. The first article (Infect Control Hosp Epidemiol 1988: 9(3):127-129) discussed the basic elements of liability law as it relates to infection control in the hospital setting. This article will focus on confidentiality in the infection control process.

Infection monitoring and control, as it occurs in most hospital settings, depends on ready access to relevant information, careful evaluation of the data, and appropriate communication of conclusions and recommendations. Equally obvious, however, is the risk associated with free-floating information of this significance. Infection control programs produce a multitude of documents that are of potential interest to outsiders such as fellow staff members, other health care institutions, and attorneys. Without specific attention to mechanisms for protecting its confidentiality, information gathered in the infection control process may well become available to some or all of those interested parties.

Much of clinical and hospital epidemiology involves the identification and enumeration of cases or the comparison of case frequencies between two or more groups of interest. Because both of these activities involve the use of statistics, it is important to pay careful attention to biostatistical issues involved in the collection and the analysis of such data.

In this article, the first in a series of biostatistical papers, we discuss some general issues that are important in the design, analysis, and interpretation of clinical epidemiologic data. Subsequent papers in this series will deal with specific methods of analysis, examples of these methods of analysis, and limitations and interpretations of the methods.