Cedric Edwards

Temporary Hemodialysis Catheter Placement by Nephrology Fellows: Implications for Nephrology Training

The insertion of temporary hemodialysis catheters is considered to be a core competency of nephrology fellowship training. Little is known about the adequacy of training for this procedure and the extent to which evidence-based techniques to reduce complications have been adopted. We conducted a web-based survey of Canadian nephrology trainees regarding the insertion of temporary hemodialysis catheters. Responses were received from 45 of 68 (66%) eligible trainees. The median number of temporary hemodialysis catheters inserted during the prior 6 months of training was 5 (IQR, 2-11), with 9 (20%) trainees reporting they had inserted none. More than one-third of respondents indicated that they were not adequately trained to competently insert temporary hemodialysis catheters at both the femoral and internal jugular sites. These findings are relevant to a discussion of the current adequacy of procedural skills training during nephrology fellowship. With respect to temporary hemodialysis catheter placement, there is an opportunity for increased use of simulation-based teaching by training programs. Certain infection control techniques and use of real-time ultrasound should be more widely adopted. Consideration should be given to the establishment of minimum procedural training requirements at the level of both individual training programs and nationwide certification authorities.

Assessment of vancomycin use in chronic haemodialysis patients: room for improvement

BACKGROUND Vancomycin is frequently prescribed for the management of infections in haemodialysis patients. We evaluated the appropriateness of vancomycin use in our chronic haemodialysis population. METHODS Charts of all chronic haemodialysis patients who received vancomycin between 1 March 2003 and 1 March 2004 were retrospectively reviewed. Indication was assessed according to the modified Hospital Infection Control Practices Advisory Committee guidelines for vancomycin prescription. The prescribed dosing regimens were evaluated. RESULTS A total of 163 courses of vancomycin in 105 patients were assessed. Of all courses, 88% were considered to be initially appropriate, but this decreased to 63% once culture and sensitivity results were available. Use of vancomycin for the management of beta-lactam-sensitive organisms accounted for the majority of inappropriate use. The most common vancomycin-dosing regimen prescribed was 500 mg intravenously at each haemodialysis session (51%); however, considerable variability was observed. CONCLUSIONS Although the initial indication for vancomycin use was generally appropriate, inappropriate continuation of this antibiotic, failure to obtain proper cultures to guide therapy and potentially subtherapeutic dosing regimens were some of the challenges identified. Centres providing chronic haemodialysis should take steps to optimize vancomycin prescription to improve clinical outcomes and reduce the risk of antimicrobial resistance.

Reply to Dr Myers' Commentary on the Use of Automated Blood Pressure Machines in Office Blood Pressure Measurements

To the Editor: We reviewed the commentary by Dr Myers wherein he suggests that casual automated office blood pressure (AOBP) should replace resting manual office blood pressure (MOBP), and that casual readings taken with AOBP are similar to awake ambulatory blood pressure monitoring (ABPM). Dr Myers suggests that the absence of resting for AOBP readings in the Conventional Versus Automated Measurement of Blood Pressure in the Office (CAMBO) trial accounts for the discrepancy between those results and our data. Indeed, a recent study by Nikolic and colleagues reported that office BP does decrease with resting time (by 4.1 mm Hg from 5 to 10 minutes). However, we would like to point out that the resting period did not change the precision, which was remarkably poor, in both the CAMBO trial and our study. Correlation coefficients and average bias data do not paint a complete picture when one is comparing two different methods. The primary outcome of our study was the Bland-Altman analysis, and we reported wide limits of agreement ( 31, +33 mm Hg) between AOBP and ABPM, which were quite similar to that reported by Dr Myers in the CAMBO trial ( 31.9, +33.6 mm Hg) despite the difference in the AOBP resting period. The scatter plots in our study (Figure 1) and in the CAMBO study (Figure 2) are indeed strikingly similar; however, with different conclusions being drawn. We therefore find it curious that Dr Myers has chosen to ignore the wide limits of agreement between AOBP and ABPM as assessed by Bland-Altman analysis and continues to promote AOBP as a surrogate for daytime ABPM. While clearly not a surrogate for ABPM when subjected to rigorous statistical testing, AOBP is endorsed by a number of national professional organizations in their guidelines for the diagnosis and management of office hypertension. According to these guidelines (National Institute for Health and Clinical Excellence [NICE], European Society of Hypertension [ESH], and Canadian Hypertension Education Program [CHEP], to name just a few), AOBP should be measured in a similar manner as MOBP. We, therefore, take issue with Dr Myers’ claim that AOBP measurements should not be preceded by a period of rest ostensibly because it led to an underestimation of daytime ABPM in those studies where proper office resting technique was used. Here, again, the reader needs to be reminded that just because the average bias was less with nonresting AOBP, this does not mean that there was any improvement in diagnostic accuracy. Except for data from one study, which was a post hoc analysis in a substudy of a larger trial using unconventional definitions, the published literature suggests that compared with MOBP, the mean BP from a series of readings by an AOBP device is lower not only among individuals with white-coat hypertension, but also among individuals who do not have the white-coat effect. This downward bias means that the price for a partial elimination of white-coat effect is an increased number of missed patients with masked hypertension. Rather than changing time-tested guidelines for the diagnosis of office hypertension, we suggest that a more accurate understanding of the role of AOBP be promoted.