Ultrasound-Guided Catheter Insertion Did Not Decrease Catheter-Related Blood Stream Infection in Hematological Oncology Care Unit

Background: Central venous catheters (CVCs) are necessary for critically ill patients requiring intravenous pharmacological intervention and subsequent parenteral nutritional support. Although CVCs allow delivery of medications and nutritional support that cannot be administered safely through central venous, their use is inevitably associated with adverse events, mechanical complication and catheter-related infection. While ultrasound guide has already been proven to decrease mechanical complications, it is not fully elucidated whether ultrasound guide decrease the risk of catheter-related infection.

Methods: We observed consecutive CVC insertions between April 2009 and January 2013. In total, 395 insertion cases were surveyed in the hematological oncology unit. We divided the research period into two terms: before December 2011 (early term) and after January 2012 (latter term). Between the early and latter terms, there were substantial differences regarding the use of ultrasound guides. Because insertion maneuvers changed from blind to ultrasound-guided approach after 2012. SMAC Plus MicroNeedle (15G, 13 cm or 12G, 20 cm; Covidien Tokyo, Japan) was used. Practitioners determined which CVC device and which insertion site was preferred for each patient. To determine the clinical efficacy of chlorhexidine gluconate dressing (CHGD) at catheter insertion site, we performed matched cohort analysis among the patients who underwent stem cell transplantation. Total 44 cases were included in the cohort from the total study population.

Results: Underlying diseases included hematological malignancies and immunological disorders such as auto-immune diseases and solid organ malignancies. A total of 235 and 160 cases were included in early and latter terms, respectively. Insertion duration was a median 26 days (range, 2-126 days) in the early term and 18 days (range, 2-104) in the latter term. During the early term, the insertion sites were 22.6%, 40.2%, and 25.7% at the cervical, subclavian, and femoral veins, respectively, and 32.3%, 16.9%, and 25.4% in the latter term, respectively. The ultrasound-guided insertion method became a routine practice in the latter term. The frequency of catheter-related blood stream infection (CRBSI) was 8.46/person-days and 13.62/person-days in the early and latter terms, respectively. Mechanical comorbidities decreased from 0.39 (13/33) incidences/month to 0.00 (0/13) after the introduction of the ultrasound-guided insertion method. Using subgroup analysis, detected causative pathogens of CRBSI did not differ between the two terms: gram-positive coccus, gram-positive bacillus, and gram-negative bacillus were 68.9%, 11.5%, and 14.8% in the early term and 68.2%, 11.4%, and 18.2% in the latter term, respectively. Controlled-cohort study revealed CHGD decreased CRBSI caused by Staphylococcus spp. significantly, but not overall other organisms.

Conclusion: Ultrasound-guided insertion did not decrease the incidence of CRBSI. However, in our survey, insertion through the cervical vein approach clearly increased after the introduction of the ultrasound-guided method, and mechanical complications decreased significantly. Ultrasound guide and cervical vein approach trended for patients with hematological diseases who required CVC and those who concurrently harbored multiple risks, including thrombocytopenia. The prevalence of CRBSI slightly increased with this trend. With respect to CRBSI, the preventative effect of CHGD in patients undergoing allogeneic stem cell transplantation was promising. We advocate trending of ultrasound-guided, cervical approach CVC with CHGD can provide the safest parental alimentation for the patients with hematological malignancies.