INFLUENCE OF PATIENT POSITION ON WITHDRAWAL FORCES DURING REMOVAL OF LUMBAR EXTRADURAL CATHETERS

We have investigated the force required to remove lumbar extradural ca theters from 88 parturients to determine the effects of patient positi oning at removal, relative to the position at insertion. Parturients w ere allocated randomly to one of four groups: LS (lateral insertion, s itting withdrawal), LL (lateral insertion, flexed lateral withdrawal), SL (sitting insertion, lateral withdrawal) or SS (sitting insertion, sitting withdrawal). In both positions, the lumbar spine was kept maxi mally flexed. The force required to remove the catheter was measured a t withdrawal. We found that the withdrawal force was influenced by the relationship between the position at removal and that at insertion, a nd we recommend that for ease of removal, patients should be placed in the same position as they were at the time of insertion. Compared wit h all other groups, the withdrawal force in patients in group LS was s ignificantly greater (P<0.05).