These findings can be generalized to the inpatient setting, where hospitalists have the opportunity to influence and modify prescribing practices in the elderly population.
5. Lessnau KD. Is chest radiography necessary after uncomplicated insertion of a triplelumen catheter in the right internal jugular vein, using the anterior approach? Chest. 2005;127:220-3.
The routine use of chest radiography to confirm proper triplelumen catheter (TLC) placement may be an unnecessary and costly intervention. Lessnau conducted a prospective observational study of 100 consecutive patients over a 4-month period who required non-urgent TLC placement. The primary operators of the procedure included 18 medical residents, 3 pulmonary fellows, and a pulmonary attending with supervision provided for more junior clinicians. Operators followed a standardized approach to TLC placement utilizing the anterior approach to the right internal jugular vein. Complicated procedures were predefined as any procedure that required more than 3 needle passes, resulted in hemorrhage or hematoma formation (where there was concern for pneumothorax), or an absence of blood return in any of the TLC’s lumens. All subjects underwent routine post-procedure chest radiography to determine proper placement of the catheter and to exclude pneumothorax. A blinded radiologist reviewed these images.
Ninety-eight of the 100 catheters were in proper position. One malpositioned catheter was 7 cm above the right atrium in a patient who was 215 cm (>7 feet) tall. The second was noted to be in an S-shaped position on chest radiography. This procedure had required 20 needle passes and 5 slides of the catheter; additionally, blood return was inadequate in 2 lumens of the catheter. An operator reported a possible complication in 10 other procedures, but the only clinical finding in these cases was the development of a local hematoma in 1 patient. Eighty-eight patients had uncomplicated insertions and had normal chest radiographs. There were no pneumothoraces.
This study demonstrates that in carefully controlled and supervised situations, as described in the study, routine chest radiography may be omitted if the insertion goes smoothly. It is important to note that these results are specific to the technique described in the study (using the anterior approach to the right internal jugular, using a short finder needle to initially locate the vein) and cannot be extrapolated to other methods of TLC insertion. Important limitations of the study include the sample size of only 100 patients and the use of only a single anatomic approach to TLC insertion. These findings, although an important first step, will need to be reproduced on a larger scale before we can recommend the cessation of routine chest radiography after TLC placement on a more widespread basis.
6. Safdar N, Fine JP, Maki DG. Metaanalysis: methods for diagnosing intravascular devicerelated bloodstream infection. Ann Intern Med. 2005;142:451-66.
Intravascular device (IVD)–related blood stream infections are a frequent cause of morbidity and mortality, and yet there is lack of a clear consensus on the most accurate method to make this diagnosis.
In this metaanalysis, Safdar et al. reviewed 185 studies, including 8 different diagnostic tests, for the detection of IVD-related bloodstream infections, of which 51 studies met the inclusion criteria. Tests were divided into IVD-sparing and those requiring IVD removal. Pooled sensitivity and specificity, summary measures of accuracy, and the mean log odds ratio were determined. The most accurate IVD-sparing test was paired quantitative blood cultures (simultaneous blood cultures from the IVD and a peripheral site, with a positive result defined as an IVD-site microorganism concentration 3–5 times greater than peripheral site) with a sensitivity of 0.87 (95% CI: 0.83–0.91) and specificity of 0.98 (95% CI: 0.97–0.99). This was followed by quantitative IVD-drawn blood cultures alone (positive result defined as growth of ≥100 CFU), with a sensitivity of 0.77 (95% CI: 0.69–0.85) and a specificity of 0.90 (95% CI: 0.88–0.92). IVD-drawn qualitative blood cultures had a sensitivity of 0.87 (95% CI: 0.80–0.94) and a specificity of 0.83 (95% CI: 0.78–0.88), and IVD- and peripheral-drawn qualitative blood cultures with differential time to positivity had a sensitivity of 0.85 (95% CI: 0.78–0.92) and specificity of 0.81 (95% CI: 0.81–0.97).