Joan Faoagali

A prospective, randomized trial of rifampicin-minocycline-coated and silver-platinum-carbon-impregnated central venous catheters

Objective:Central venous catheters are the predominant cause of nosocomial bacteremia; however, the effectiveness of different antimicrobial central venous catheters remains uncertain. We compared the infection rate of silver-platinum-carbon (SPC)-impregnated catheters with rifampicin-minocycline (RM)-coated catheters. Design:A large, single-center, prospective randomized study. Setting:Twenty-two-bed adult general intensive care unit in a large tertiary metropolitan hospital in Brisbane, Australia (2000–2001). Patients:Consecutive series of all central venous catheterizations in intensive care unit patients. Interventions:Randomization, concealment, and blinding were carefully performed. Catheter insertion and care were performed according to published guidelines. Blood cultures were taken at central venous catheter removal, and catheter-tip cultures were performed by both roll-plate and sonication techniques. Pulsed field gel electrophoresis was used to establish shared clonal origin for matched isolates. Measurements and Main Results:Central venous catheter colonization and catheter-related bloodstream infection were determined with a blinded technique using the evaluation of the extensive microbiological and clinical data collected and a rigorous classification system. Six hundred forty-six central venous catheters (RM 319, SPC 327) were inserted, and 574 (89%) were microbiologically evaluable. Colonization rates were lower for the RM catheters than SPC catheters (25 of 280, 8.9%; 43 of 294, 14.6%; p = .039). A Kaplan-Meier analysis that included catheter time in situ did not quite achieve statistical significance (p = .055). Catheter-related bloodstream infection was infrequent for both catheter-types (RM 4, 1.4%; SPC 5, 1.7%). Conclusions:The SPC catheter is a clinically effective antimicrobial catheter; however, the RM catheter had a lower colonization rate. Both catheter types had low rates of catheter-related bloodstream infection. These results indicate that future studies will require similar rigorous methodology and thousands of central venous catheters to demonstrate differences in catheter-related bloodstream infection rates.

Catheter-associated bloodstream infection incidence and risk factors in adults with cancer: a prospective cohort study

Central venous catheter-associated bloodstream infections (CABSIs) cause considerable morbidity in patients with cancer. We determined the incidence and risk factors for CABSI by performing a prospective observational cohort study of all adult patients requiring a central venous access device (CVAD) in a haematology-oncology unit. All CVADs were inserted under ultrasound guidance by trained operators in a dedicated interventional radiology facility. A total of 1127 CVADs were assessed in 727 patients over 51,514 line-days. The rate of CABSI per 1000 line-days was 2.50. Factors associated with CABSI included: type of CVAD, greatest for non-tunnelled lines [hazard ratio (HR): 3.50; P < 0.0001] and tunnelled lines (HR: 1.77; P = 0.011) compared to peripherally inserted central venous catheter (PICC) lines; patient diagnosis, greatest for aggressive haematological malignancies (HR: 3.17; P = 0.0007) and least for oesophageal, colon and rectal cancers (HR: 0.29; P = 0.019) compared to other solid tumours; side of insertion, greatest for right-sided lines (HR: 1.60; P = 0.027); and number of prior line insertions (HR: 1.20; P = 0.022). In patients with aggressive haematological malignancies there was significantly more CABSI with non-tunnelled lines (HR: 3.9; P < 0.001) and a trend to more CABSI with tunnelled lines (HR: 1.43; P = 0.12) compared to patients with PICC lines, as well as increased CABSI for right-sided insertions (HR: 1.62; P = 0.047). This study highlights the utility of a standardised CABSI surveillance strategy in adult patients with cancer, provides further data to support the use of PICC lines in such patient populations, and suggests that the side of line insertion may influence risk of CABSI.

Clinical utility of hygroscopic heat and moisture exchangers in intensive care patients.

OBJECTIVE To compare the degree of bacterial circuit colonization, frequency of ventilator-associated pneumonia (VAP), character of respiratory secretions, rewarming of hypothermic patients, disposable costs, and air flow resistance in intensive care patients ventilated using either a heat and moisture exchanger (HME) or hot water (HW) humidifier circuit. DESIGN A prospective, randomized blinded trial of patients in the intensive care unit undergoing mechanical ventilation. SETTING A metropolitan teaching hospital. PATIENTS One hundred sixteen patients undergoing mechanical ventilation for a minimum period of 48 hrs were enrolled. INTERVENTIONS Patients were randomized to three ventilation groups using a) an HW circuit with a 2-day circuit change (n = 41); or b) a bacterial-viral filtering HME in the circuit, with either a 2-day (n = 42); or c) a 4-day circuit change (n = 33). MEASUREMENTS AND MAIN RESULTS Circuit colonization was assessed using quantitative culture of washings taken from the circuit tubing and semiquantitative culture of swabs from the Y connectors. Sixty-seven percent of HW circuits became contaminated compared with 12% in the two HME groups (p < .0001). Median colony counts were lower in the HME groups (p < .0001). If circuits at first circuit change were contaminated in the HW group, 89% of subsequent circuit changes became contaminated compared with 0% and 25% for the 2- and 4-day HME groups, respectively. The frequency of VAP, the time to resolution of admission hypothermia, and the volume and fluidity of secretions were similar for all groups. The resistance of the HME after 24 hrs of use was < 0.025 cm H2O/L at gas flows of 40 L/min. HME use resulted in a cost reduction of

Ethanol lock therapy to treat tunnelled central venous catheter-associated blood stream infections: Results from a prospective trial

1.48 (Australian)/day. CONCLUSIONS Circuits with a bacterial-viral filtering HME are less readily colonized by bacteria. Contamination is a random event. Humidification technique has no influence on the frequency rate of VAP, the effectiveness of rewarming, nor the character of the respiratory secretions. Breathing resistance is generally low and disposable costs are reduced when an HME is used.

Comparison of the immediate, residual, and cumulative antibacterial effects of Novaderm R, Novascrub R, Betadine Surgical Scrub, Hibiclens, and liquid soap☆☆☆★★★

In order to assess the efficacy of 70% ethanol locks in addition to antibiotic therapy to treat tunnelled central venous catheter-associated bloodstream infections, a pilot study of 19 patients was performed prospectively using ethanol locks for 5 d in addition to antibiotic therapy to treat tunnelled central venous catheter-associated bacteraemia. 12 patients had mono-microbial infections and 7 had polymicrobial isolates. 17 of 19 patients completed ethanol lock therapy. 15 of 17 patients completing ethanol lock therapy had no recurrence of the original organism and retained their catheter for a median of 36 and an average of 47 d following initiation of ethanol lock therapy. These results demonstrate the safety and potential efficacy of this technique against a broad range of potentially virulent organisms. The intervention was acceptable to both staff and patients with no significant side-effects. These preliminary results from our prospective pilot study suggest that ethanol lock therapy is safe and easily integrated into clinical practice, and may have utility in treating central venous catheter-associated infections, avoiding removal of catheters in patients requiring long-term venous access.

Double-heater-wire circuits and heat-and-moisture exchangers and the risk of ventilator-associated pneumonia

BACKGROUND Triclosan (Irgasan), an antibacterial active against staphylococci and coliform bacteria, has been formulated for use as a handwash. There has been only one previous report of the use of the glove juice test to determine the immediate, residual, and cumulative effects of a 1% triclosan-based handwash product. There have been no previous studies on the use of 1% triclosan combined with povidone-iodine (PI) in a handwash product. METHODS The glove juice technique was used to document and compare the immediate, 3-hour residual, and 5-day cumulative effects on the mean log10 bacterial counts of 1% triclosan-based handwash product and 1% triclosan with 5% PI. A standardized surgical handwashing technique was used before sample collection. These results and the identity and type of the aerobic bacteria cultured from the samples were compared with the results of standardized washing and glove juice sampling with 4% weight/volume chlorhexidine gluconate (CHG), 7.5% PI, and a nonantimicrobial liquid soap. RESULTS All five tested products showed significant log10 reduction from baseline on day 1, hour 0 (p < 0.05). There was no significant difference between the mean log10 bacterial count when 7.5% PI, 4% CHG, and 1% triclosan with 5% PI were compared with each other immediately after washing (p > 0.05). There was a significant difference between 1% triclosan and the liquid soap when they were each compared with 4% CHG, 7.5% PI, and 1% triclosan with 5% PI. There was no statistically significant difference between the 1% triclosan product and the liquid soap (p > 0.20). All products were effective at reducing the immediate bacterial count from the baseline level. All formulations except the liquid soap showed significant cumulative effect (p < 0.05) after multiple washes, with no significant difference between the cumulative effects of the liquid soap and 1% triclosan (p > 0.05). Both products differed significantly (p < 0.05) from the CHG, PI, and triclosan with PI. CHG, PI, and triclosan with PI showed effects significantly different from each other (p < 0.05). CONCLUSIONS Triclosan combined with PI resulted in the prevention of bacterial regrowth at 3 hours such as occurred when PI alone was used. Triclosan-containing products have a small cumulative effect, although not as great as that produced by CHG. The triclosan-based products did not appear to select for gram-negative bacterial overgrowth, although the study period may have been too short to detect such an effect.

Successful treatment of post-influenza pseudomembranous necrotising bronchial aspergillosis with liposomal amphotericin, inhaled amphotericin B, gamma interferon and GM-CSF

Objective:To compare the incidence of ventilator-associated pneumonia (VAP) in patients ventilated in intensive care by means of circuits humidified with a hygroscopic heat-and-moisture exchanger with a bacterial viral filter (HME) or hot-water humidification with a heater wire in both inspiratory and expiratory circuit limbs (DHW) or the inspiratory limb only (SHW). Design:A prospective, randomized trial. Setting:A metropolitan teaching hospitals general intensive care unit. Patients:Three hundred eighty-one patients requiring a minimum period of mechanical ventilation of 48 hrs. Interventions:Patients were randomized to humidification with use of an HME (n = 190), SHW (n = 94), or DHW (n = 97). Measurements and Main Results:Study end points were VAP diagnosed on the basis of Clinical Pulmonary Infection Score (CPIS) (1), HME resistance after 24 hrs of use, endotracheal tube resistance, and HME use per patient. VAP occurred with similar frequency in all groups (13%, HME; 14%, DHW; 10%, SHW; p = 0.61) and was predicted only by current smoking (adjusted odds ratio [AOR], 2.1; 95% confidence interval [CI], 1.1–3.9; p = .03) and ventilation days (AOR, 1.05; 95% CI, 1.0–1.2; p = .001); VAP was less likely for patients with an admission diagnosis of pneumonia (AOR, 0.40; 95% CI, 0.4–0.2; p = .04). HME resistance after 24 hrs of use measured at a gas flow of 50 L/min was 0.9 cm H2O (0.4–2.9). Endotracheal tube resistance was similar for all three groups (16–19 cm H2O min/L; p = .2), as were suction frequency, secretion thickness, and blood on suctioning (p = .32, p = .06, and p = .34, respectively). The HME use per patient per day was 1.13. Conclusions:Humidification technique does not influence either VAP incidence or secretion characteristics, but HMEs may have air-flow resistance higher than manufacturer specifications after 24 hrs of use.

Streptococcus bovis bacteraemia: Identification within organism complex and association with endocarditis and colonic malignancy

A case of aspergillus tracheobronchitis following influenza A infection in an immunocompetent 35 year old woman is described that required prolonged mechanical ventilation for airways obstruction. Treatment included liposomal amphotericin, inhaled amphotericin, gamma interferon and GM-CSF. Liposomal amphotericin therapy was associated with reversible hepatosplenomegaly. Inhaled corticosteroids with continued antifungal therapy were used for the management of severe recurrent airway obstruction. After a prolonged course of treatment she survived with fixed airways obstruction unresponsive to corticosteroids.

Incubation time required for neonatal blood cultures to become positive

Aim: To identify Streptococcus bovis bacteraemia episodes and their clinical associations, including differences in associations by S. bovis biotypes (or species). Methods: The study was performed at Princess Alexandra Hospital, Brisbane. Streptococcus bovis blood culture results for 1999–2006 were retrieved. Patient data including diagnosis and investigations were retrospectively obtained from clinical records and compared with the microbiological result, including S. bovis biotype/species. Results: Twenty evaluable S. bovis bacteraemia episodes were identified. Ten were S. bovis biotype I (Streptococcus gallolyticus subspecies gallolyticus) and 10 S. bovis II. For S. bovis I infections, six patients had a diagnosis of infective endocarditis. Nine had assessment for colonic pathology and all had malignant or premalignant colonic lesions. Of patients with S. bovis II infections, two were diagnosed with endocarditis and six had a hepatobiliary source of infection. Of five patients assessed in this group, three had premalignant colonic lesions. Conclusions: Endocarditis and hepatobiliary infections were the main causes of S. bovis bacteraemia. Endocarditis was diagnosed in the majority of S. bovis I bacteraemias and all patients assessed in this group had premalignant/malignant colonic lesions. Determining S. bovis biotype/species provides information on likely clinical associations of bacteraemia episodes.

Comparison of the antibacterial efficacy of 4% chlorhexidine gluconate and 1% triclosan handwash products in an acute clinical ward

Aim:  We aimed to determine the laboratory detection time of bacteraemia in neonatal blood cultures, and whether this differed by: organism; samples deemed to represent true bacteraemia versus contaminants; and blood cultures collected from an infant <48 h of age (early) or ≥48 h of age (late).