The pulmonary artery catheter sleeve--protective or infective?

The use of sterile plastic sleeves to protect pulmonary artery catheters (PAC) may decrease infection risk. The catheter may require manipulation but contamination of the sleeve risks inoculating organisms into the patients. We sought to determine whether the sleeve remains sterile and for how long. We conducted a prospective observational study to culture the components of the PAC in a critically ill population. Upon removal we cultured 1) the PAC tip, 2) the PAC introducer exit site, 3) the PAC introducer hub and 4) a sterile irrigant solution which ran down the inside of the protective sleeve. Demographic, catheter and disease variables were also collected. There were 102 PAC episodes amounting to 3952 catheter hours with a mean duration of catheterisation of 39.1 (24.2) hours. There were 17 positive culture results, of which six were positive sleeve fluid cultures. In three of these patients the exit site was culture positive, and the same organism was isolated as within the sleeve. No patient had a positive blood culture. There was no difference between those with and without a positive sleeve culture in terms of demographic or disease variables. The protective sleeve of the pulmonary artery catheter does not remain sterile and should not be considered as a sterile barrier. We believe that manipulating the PAC within the sleeve carries the risk of inoculating the patient with pathogenic organisms. The duration of sterility remains to be determined.

Screening and electronic labelling of ward contacts of vancomycin-resistant Enterococcus faecium vanB carriers during a single-strain hospital outbreak and after discharge from hospital

A large single-strain outbreak of vancomycin-resistant Enterococcus faecium (VREF) vanB occurred in Royal Perth Hospital from July to December 2001. When a VREF-carrying patient was discovered on a ward, all patients on the ward were screened with rectal swabs. A total of 172 patients were colonised, four with infections, but no deaths were attributable to VREF. The number of rectal swabs required to detect each carrier was recorded. On average four rectal swabs, each collected on separate days, were needed to detect more than 90 per cent of the 172 VREF carriers who were epidemiologically linked to the Royal Perth Hospital outbreak. An electronic alert system (Micro-Alert) was used to identify ward contacts of VREF carriers and enabled those who had not been screened before discharge to be followed-up and screened. Ninety-six contacts were actively followed-up in October 2001 and 32 (33.3%) were found to be VREF carriers. From 28 September 2001 to 30 April 2002, a total of 1,977 ward contacts were screened after discharge from hospital and 54 (2.73%) were found to be carrying VREF. We conclude that during single-strain outbreaks of vancomycin-resistant enterococci in hospitals, patient contacts need to be screened on more than three occasions in order to detect most of the carriers and control the outbreak. Secondly, electronic labelling and active follow-up of ward contacts of VREF carriers resulted in a significant number of carriers being detected who otherwise posed a risk of initiating further outbreaks in hospitals if they were readmitted.

A rapid (20 h) solid screening medium for detecting methicillin-resistant Staphylococcus aureus

Methicillin aztreonam mannitol salt agar is a sensitive and reliable solid screening medium for detecting methicillin-resistant Staphylococcus aureus (MRSA). With this medium an incubation period of only 20 h is sufficient to either produce visible colonies of MRSA or to exclude MRSA (no staphylococcal colonies). Coagulase testing (requiring a further 6 h) enables coagulase-positive isolates to be provisionally reported as 'possible MRSA' 26-30 h after the swabs were collected. The medium supports growth of intrinsically resistant staphylococci including low-expression-class MRSA (methicillin minimum inhibitory concentration (MIC) 8-16 mg/L), but methicillin susceptible staphylococci and beta-lactamase hyperproducers are suppressed.

Use and abuse of psychiatric emergency services

The pattern of use of psychiatric emergency services of a large university hospital are examined for a twelve month period. Factors associated with social isolation and poverty were found to be linked both with multiple episodes and disposition to a public facility. The implications for health planners are discussed.