Prospective controlled cohort study of Troponin I levels in patients undergoing elective spine surgery for degenerative conditions: prone versus supine position

Journal Publication ResearchOnline@JCU
Macfarlane, A.I.;Rudd, D.;Knight, E.;Marshman, L.A.G.;Guazzo, E.P.;Anderson, D.S.
Donna Rudd
Abstract

Prior studies have suggested that elevated serum Troponin-I (TnI) levels immediately after non-cardiac surgical procedures (8–40%) represent subclinical cardiac stress which independently predicts increased 30-day mortality. Routine post-operative TnI monitoring has therefore been suggested as a standard of care. However, no prior studies have focussed on elective degenerative spine surgery, whilst few have measured pre-op TnI. Further, prolonged prone positioning could represent an additional, independent, cardiac stress. We planned a prospective controlled cohort study of consecutive TnI levels in routine elective spine surgery for degenerative spine conditions, incorporating 3 groups: ‘prone < 2 h’, ‘prone > 2 h’ and ‘supine’ positioning. TnI levels (>0.04 μg/L) were recorded immediately pre-/post-surgery, and by 24 h of surgery. N = 120 patients were recruited. Complete results were obtained in 92 (39 supine, 53 prone). No significant between-groups differences were observed in demographic or cardiovascular risk factors. Validated TnI-elevation by 24 h was not observed in any group. Spurious elevations were recorded in one ‘prone < 2 h’ and one ‘prone > 2 h’. One non-ST segment myocardial infarction (STEMI) occurred on day 7 without TnI elevation by 24 h (prone > 2 h). There was no 30-day mortality. Conclusions: Despite a lower cut-off, no validated TnI elevation was observed in any group by 24 h after surgery. One non-STEMI had not been associated with TnI-elevation by 24 h. Immediately peri-operative cardiac stress therefore appeared comparatively rare in patients undergoing routine elective spine surgery. Further, prone positioning did not represent an additional, independent, risk. Routine immediately post-operative TnI monitoring in elective spine surgery therefore appears unjustified. Our study highlighted several caveats regarding consecutive TnI testing.

Journal

Journal of Clinical Neuroscience

Publication Name

Journal of Clinical Neuroscience

Volume

35

ISBN/ISSN

1532-2653

Edition

N/A

Issue

N/A

Pages Count

5

Location

N/A

Publisher

Elsevier

Publisher Url

N/A

Publisher Location

N/A

Publish Date

N/A

Url

N/A

Date

N/A

EISSN

N/A

DOI

10.1016/j.jocn.2016.09.008