Withdrawal forces of lumbar spinal catheters: no dependence on body position A. Michalek-Sauberer, M.J. Oehmke, G. Scharbert, K. Neumann, S.A. Kozek-Langenecker, E. Deusch British Journal of Anaesthesia Volume 100, Issue 6, Pages 846-849 (June 2008) DOI: 10.1093/bja/aen086 Copyright © 2008 British Journal of Anaesthesia Terms and Conditions
Fig 1 Withdrawal force measurement of the spinal catheter by a tension spring balance with a drag indicator calibrated to Newton (N). (a) Indicator and drag indicator were set to 0 N. Calibration to 0 N is done by turning the set screw on the top of the tension spring balance. (b) The spring balance was clamped to the spinal catheter and a constant retraction force was applied. (c) The maximum force needed for removal of catheter was read off the drag indicator. British Journal of Anaesthesia 2008 100, 846-849DOI: (10.1093/bja/aen086) Copyright © 2008 British Journal of Anaesthesia Terms and Conditions
Fig 2 Withdrawal forces of lumbar midline continuous spinal catheters in sitting or flexed lateral positions. The boxes in the box-whisker plot indicate median and first to third quartile; the bars show smallest to largest non-outlier observation. Circles and asterisks mark outliers and extreme outliers. British Journal of Anaesthesia 2008 100, 846-849DOI: (10.1093/bja/aen086) Copyright © 2008 British Journal of Anaesthesia Terms and Conditions