Korean J Anesthesiol.  2011 Aug;61(2):138-142. 10.4097/kjae.2011.61.2.138.

Effect of airway pressure on lumbar epidural pressure during positive pressure ventilation

• Han SS
• Lim YJ
• Jeon Y
• Min KB
• Ahn WS
• Lee SC

• KMID: 1766708
• DOI: http://doi.org/10.4097/kjae.2011.61.2.138

Abstract

BACKGROUND
The purpose of this study was to measure lumbar epidural pressure (EP) during the insertion of a Tuohy needle under general anesthesia and to evaluate the influence of airway pressure on EP.
METHODS
Lumbar EP was measured directly through a Tuohy needle during intermittent positive pressure ventilation in fifteen patients. Mean and peak EP were recorded after peak inspiratory pressures (PIP) of 0, 15, and 25 cmH2O.
RESULTS
All measured lumbar EPs were positive, with the pressure increasing during inspiration and decreasing during expiration. Median EP was 6.0 mmHg (interquartile range, 4.0-8.0) at 0 cmH2O of PIP, 6.5 mmHg (4.5-8.5) at 15 cmH2O, and 8.5 mmHg (6.0-10.5) at 25 cmH2O, increasing significantly at 15 cm H2O PIP, and further increasing at 25 cmH2O (P < 0.001).
CONCLUSIONS
We demonstrate the influence of increased airway pressure on lumbar EP measured directly through a Tuohy needle. Lumbar EPs were positive, and increasing PIP levels significantly increased lumbar EP.

Keyword

Epidural pressure; General anesthesia; Lumbar

MeSH Terms

Anesthesia, General
Humans
Intermittent Positive-Pressure Ventilation
Needles
Positive-Pressure Respiration