All that glisters?How to assess the ?value? of a scientific paper

Volatile anaesthetic depression of the carotid body chemoreflex-mediated ventilatory response to hypoxia: directions for future research

In assessing whether volatile anaesthetics directly depress the carotid body response to hypoxia it is necessary to combine in meta-analysis studies of when it is "functionally isolated" (e.g., recordings are made from its afferent nerve). Key articles were retrieved (full papers in English) and subjected to quantitative analysis to yield an aggregate estimate of effect. Results from articles that did not use such methodology were assessed separately from this quantitative approach, to see what could be learned also from a nonquantitative overview. Just 7 articles met the inclusion criteria for hypoxia and just 6 articles for hypercapnia. Within these articles, the anaesthetic (mean dose 0.75, standard deviation (SD) 0.40 minimum alveolar concentration, MAC) statistically significantly depressed carotid body hypoxic response by 24% (P = 0.041), but a similar dose (mean 0.81 (0.42) MAC) did not affect the hypercapnic response. The articles not included in the quantitative analysis (31 articles), assessed qualitatively, also indicated that anaesthetics depress carotid body function. This conclusion helps direct future research on the anaesthetic effects on putative cellular/molecular processes that underlie the transduction of hypoxia in the carotid body.

Declining randomized clinical trials from Canadian anesthesia departments?

PURPOSE

The research productivity was estimated by publications from anesthesiology departments at Canadian universities over a five-year period, and the articles published were classified into several study designs.

METHODS

In this observational study, the MEDLINE database was searched for publications listed by anesthesiology departments at Canadian universities as the primary corresponding source from 2000-2004. Abstracts were reviewed and each publication categorized into its respective methodological design. Impact factors of the journals in which the articles appeared were taken into consideration. "Total impact score" was defined as the total number of articles from a particular journal in a particular year multiplied by the impact factor value. Changes in overall publication numbers over the five-year period were compared and analyzed using Pearson correlation coefficients.

RESULTS

Total Canadian anesthesia publications remained constant from 2000-2004. In this five-year time frame, the University of Toronto had the highest number of publications (271) followed by the University of Montreal (86), and McGill University (84). These universities conducted primarily randomized controlled trials (RCTs) whereas smaller Canadian universities mainly published case reports, reviews, and cohort studies. The number of RCTs conducted seems to be decreasing whereas the number of case reports and reviews being published are remaining constant over the five-year period.

CONCLUSION

Although overall numbers in anesthesia publications do not suggest a significant decline, the number of RCTs decreased during the years 2000-2004. The quality of anesthesia research appears to be comparable to those in other medical specialties, with larger institutions conducting RCTs and smaller institutions publishing more case reports.