Best Evidence Topics

Randomised control trial

Julie Leung, MBBS, BSc; Martin Duffy, MBBS; Andrew Finckh, MBBS, BA
Real-Time Ultrasonographically-Guided Internal Jugular Vein Catheterization in the Emergency Department Increases Success Rates and Reduces Complications: A Randomized, Prospective Study
Annals of Emergency Medicine
November 2006; Pages 540-547
  • Submitted by:Matthew Flannigan - Emergency Medicine Resident
  • Institution:Grand Rapids Medical Education and Research/Michigan State University
  • Date submitted:4th March 2007
Before CA, i rated this paper: 7/10
1 Objectives and hypotheses
1.1 Are the objectives of the study clearly stated?
  Yes. Comparison of real-time ultrasound-guided insertion of internal jugular central venous catheter insertion in the emergency department compared to traditional landmark techniques.
2 Design
2.1 Is the study design suitable for the objectives
  Yes, prospective randomized control trial.
2.2 Who / what was studied?
  Rate of successful insertion of internal jugular venous catheter, number of attempts, access time, and complication rates in adults in the emergency department with an indication for central venous access.
2.3 Was this the right sample to answer the objectives?
2.4 Is the study large enough to achieve its objectives? Have sample size estimates been performed?
  Yes. Calculated target sample size was 360 for a power of 80% and p=0.5; but the study was allowed an early cutoff level if there were >100 patients and had a P <0.01, which was achieved.
2.5 Were all subjects accounted for?
2.6 Were all appropriate outcomes considered?
  Yes, the main outcome was the rate of successful insertion of internal jugular central venous catheter within three attempts. Secondary outcome measures were the number of attempts required, access times, and complication rates.
2.7 Has ethical approval been obtained if appropriate?
  Yes, informed consent from participants was obtained and the study was approved by the hospital's ethics committee.
2.8 Were the patients randomised between treatments?
2.9 How was randomisation carried out?
  Computer block randomization was used and allocation assignments were concealed.
2.10 Are the outcomes clinically relevant?
  Yes. Successful cannulation of internal jugular vein with ultrasound-guidance occurred in 61 of 65 patients (93.9%) vs. 51 of 65 patients (78.5%) using landmark techniques, a significant difference of 15.4% (p=0.009; 95%CI 3.8-27%) Complcation rates were 16.9% in the landmark technique vs. 4.6% in the ultrasound-guided group, a difference of 12.3% (95%CI 1.9 to 22.8%). Mean number of attempts were 1.3 with ultrasound-guidance vs. 1.6 with landmark techniques. Access times were not significantly different with either method.
3 Measurement and observation
3.1 Is it clear what was measured, how it was measured and what the outcomes were?
  Yes. Successful rate of internal jugular central venous catheter insertion, number of attempts required, access time, and complication rate in emergency department patients requiring central venous access.
3.2 Are the measurements valid?
3.3 Are the measurements reliable?
3.4 Are the measurements reproducible?
3.5 Were the patients and the investigators blinded?
  No. Due to the nature of the study, it was impossible to blind the operator from the intervention. Operators were knowledgeable of outcome variables (complication rates, access times, and number of attempts) were being measured, potentially introducing a Hawthorne Effect. In addition, enrollment was non-consecutive, potentially creating an assembly bias.
4 Presentation of results
4.1 Are the basic data adequately described?
  Yes in tables 3 and 4.
4.2 Were groups comparable at baseline?
  Unfortunately, baseline characteristics favored improved outcomes in the landmark group. Therefore, there is a potential that the measured outcomes would have been stronger in the ultrasound-guided group, had they been more evenly balanced.
4.3 Are the results presented clearly, objectively and in sufficient detail to enable readers to make their own judgement?
4.4 Are the results internally consistent, i.e. do the numbers add up properly?
4.5 Were side effects reported?
  Yes in Table 3 and described in the results section.
5 Analysis
5.1 Are the data suitable for analysis?
5.2 Are the methods appropriate to the data?
5.3 Are any statistics correctly performed and interpreted?
  Yes. The main outcome was successful insertion of a central venous catheter in the internal jugular vein using a Chi-squared analysis. Secondary measures of number of attempts and complication rates were interpreted through chi-squared analysis. Access time was interpreted by a two-sample t-test.
6 Discussion
6.1 Are the results discussed in relation to existing knowledge on the subject and study objectives?
6.2 Is the discussion biased?
  No. It acknowledges that several prior studies have yielded higher success rates with ultrasound-guided central venous catheter insertions and fewer complication rates. This study appears to be more widely applicable because 8 of its 15 operators were inexperienced (performed <25 internal jugular central venous catheter insertions), perhaps more closely representing the skills of current emergency department physicians.
7 Interpretation
7.1 Are the authors' conclusions justified by the data?
7.2 What level of evidence has this paper presented? (using CEBM levels)
7.3 Does this paper help me answer my problem?
  Yes. Ultrasound-guided internal jugular central venous catheter insertion offers a higher rate of successful cannulation, irregardless of operator experience, with fewer attempts and complications, without a significant increase in access time compared to traditional landmark techniques in the emergency department setting.
After CA, i rated this paper: 5/10
8 Implementation
8.1 Can any necessary change be implemented in practice?
  Yes. Utilization of ultrasound-guided internal jugular vein catheterization should be considered as a practice standard for central venous access in emergency department patients.
8.2 What aids to implementation exist?
  There is an increasing level of public and medical society concern regarding preventable iatrogenic complications; ultrasound-guided central venous catheter insertion would aid in reducing these complications.
8.3 What barriers to implementation exist?
  Each emergency department would require a capital expenditure to purchase an ultrasound machine and require a training of its physicians in venous access techniques.