E.M. Cooke

The cost of infection in surgical patients: a case-control study

To determine the excess hospital cost attributable to hospital acquired infection in a UK hospital 67 surgical patients with hospital acquired infection (HAI) were matched with uninfected controls on the primary features of the first operative procedure and primary diagnosis, and on the secondary features of sex, age and surgical service. Costs were calculated from the hospitals unit costs for pathology, radiology and for the cost of one days extra stay. The mean cost of one day of antibiotic therapy was also measured. In infected patients there was a significant increase in the length of hospital stay of 8.2 days with a mean extra cost per patient of 1041 pounds (P < 0.001). Microbiology, haematology, chemical pathology and radiology requests were all significantly increased with a mean extra cost per infected patient of 10.4 pounds, 7.8 pounds, 96. pounds, and 3.3 pounds, respectively. Antibiotic therapy contributed significantly to the extra costs (44 pounds per infected patient). The mean extra cost per patient was highest in orthopaedic patients (2646 pounds) and least in gynaecology patients (404 pounds). For the infections with significantly increased cost, multiple infections carried the greatest (3362 pounds), and urinary tract infections the least (467 pounds) cost. Hospital length of stay was the greatest contributor to the cost and accounted for 95% of the extra cost in orthopaedics, 94% in gynaecology and 92% in general surgery and urology. Antibiotic therapy was the second most significant contributor to cost and, with the exception of urinary tract infection and infections in gynaecology, was at least five times more per patient than requests for microbiology, haematology, chemical pathology or radiology.

An evaluation of surveillance methods for detecting infections in hospital inpatients

Eight selective surveillance methods were compared with a reference method for their ability to detect hospital infections in patients was also assessed. In the reference method, case records were reviewed three times a week, and during the 11-month period of study, 668 infections were identified amongst 3326 patients. Three hundred and thirty-eight were community acquired infections (CAI) and 330 were hospital acquired infections (HAI). The time for data collection was 18.1 h per 100 beds per week. Of the selective surveillance methods, those based on the review of treatment and temperature charts detected the highest proportion (70%) of CAI; and the review of microbiology reports with regular ward liaison identified the highest proportion (71%) of HAI. The time for data collection in the eight methods ranged from 1.2 h per 100 beds per week to 6.5 h per 100 beds per week. After considering the sensitivity for identifying patients with HAI and time for data collection, the review of microbiology reports with regular ward liaison was judged to be an effective and efficient method of surveillance.

Review of case definitions for nosocomial infection — towards a consensus

As part of the preparatory work for a national surveillance scheme, consensus was sought on the case definitions for nosocomial infection. We compare six sets of case definitions for nosocomial urinary tract infection, surgical wound infection, bloodstream infection and pneumonia, and highlight areas of agreement and variation. We hope this will stimulate discussion among those with expertise and interest in surveillance and so contribute to the development of nationally agreed case definitions.

Methicillin-resistant Staphylococcus aureus in the UK and Ireland. A questionnaire survey.

The results of a questionnaire survey of the distribution of methicillin-resistant Staphylococcus aureus (MRSA) in the UK and Ireland between 1982 and 1983 are reported. Information was obtained about the geographical distribution of MRSA, the units affected, the sites of isolation and the preventive measures employed. Serious clinical problems were confined to a small number of hospitals with high isolation rates of MRSA.

An 11-month incidence study of infections in wards of a district general hospital

Between March 1988 and January 1989, an incidence study of infections in patients occupying 122 beds in a district general hospital was undertaken. Nursing notes, medical notes, temperature charts, drug prescription charts and laboratory information were reviewed three times a week to determine if patients had infection which met strict case definitions. In addition, the surveyor consulted with ward nursing and medical staff for clarification of symptoms and signs indicative of infection. During the study, 668 infections were identified amongst 3326 patients. Three hundred and thirty-eight (51%) were community-acquired infections (CAI) and 330 hospital-acquired infections (HAI). Excluding 24 HAI acquired in other hospitals, the incidence rates were 9.2 HAI per 100 discharges, and 1.1 HAI per 100 patient days. The common types of CAI were pneumonia, abdominal infection and urinary tract infection. The main types of HAI were urinary tract infection, surgical wound infection and pneumonia. The microorganisms most frequently associated with CAI and HAI were Gram-negative bacilli.

Introduction of laboratory based ward liaison surveillance of hospital infection into six district general hospitals

A previous study demonstrated that laboratory based ward liaison surveillance (LBWLS) of hospital infection was an effective and efficient method. The method involved the follow-up of positive microbiology reports by the review of patient records and liaison with ward nursing staff to consider whether any patients had infection. Here we report the introduction of LBWLS into six district general hospitals to determine whether it is feasible to use this method on an everyday basis. The time required for data collection was assessed and the method was compared with a reference method in one hospital to check its ability to detect infections. To assess reproducibility two infection control nurses (ICNs) performed LBWLS independently, but concurrently, for 5 weeks. The method could be used in all hospitals studied; however, the time for data collection ranged from 3.0 to 6.8 h/100 beds per week. In comparison with the reference method, LBWLS detected 15/41 (37%) of community acquired infections and 30/43 (70%) of hospital acquired infections. In the reproducibility assessment 72 patients were identified by both ICNs. There was agreement about the infected/non-infected status of 65 of these patients. The mean pair agreement and Kappa statistic were 0.88 and 0.72. Laboratory based ward liaison was readily used in all hospitals and was reproducible.