• The primary end-point will be the incidence of spontaneous paraesthesia during catheter insertion in TEA-patients. [ Time Frame: 1 hour ] [ Designated as safety issue: Yes ]
  

• The frequency of inadvertent vascular cannulation [ Time Frame: 1 hour ] [ Designated as safety issue: Yes ]
  
• Difficulties involved in insertion and removal of the catheter [ Time Frame: 1 week ] [ Designated as safety issue: Yes ]
  
• Data on additional complications [ Time Frame: 1 week ] [ Designated as safety issue: Yes ]
  
• Data for the evaluation of handling characteristics [ Time Frame: 1 week ] [ Designated as safety issue: No ]
  

Epidural anaesthesia is a central neuraxial block technique with many applications. Improvements in equipment, drugs and technique have made it a popular and versatile anaesthetic technique, with applications in surgery, obstetrics and pain control. Both single injection and catheter techniques can be used. Its versatility means it can be used as an anaesthetic, as an analgesic adjuvant to general anaesthesia, and for postoperative analgesia in procedures involving the lower limbs, perineum, pelvis, abdomen and thorax.

Although epidural anaesthesia is a safe technique, during the insertion of epidural catheters several side effects may occur, including transient paraesthesia and inadvertent vascular cannulation.

Reported incidences for paraesthesia vary widely between about 0.2% and 50% in different articles, depending on the catheter (catheter material, soft-tipped or firm-tipped catheter), the applied technique (lumbar or thoracic epidural anaesthesia, depth of catheter insertion), the approach (midline or paramedian) and the included patients (obstetrical or non-obstetrical). Paraesthesias are not supposed to lead to permanent neurological sequelae, but are unpleasant and perturbing sensations for the patient.

Besides inadvertent intrathecal location of the catheter, further problems include technical difficulties during threading or removal of the catheter. Here, the catheter shaft material seems to be the crucial factor for the incidence of problems.

Based upon years of experience, a wide range of epidural catheters were created, among them the Perifix catheter of B. Braun. Common features are their high tensile strength and stretch resistance, excellent shaft stability with easy visualisation of blood or spinal fluid due to the crystal clear material, no risk of forming loops or knots, and softening of catheter within a few hours due to water absorption of the polyamide material.

Recently, B. Braun Melsungen AG has developed a new generation of Perifix epidural catheters, which are already CE-labeled. These new catheters are different in their composition compared to the current Perifix Standard catheter with regard to the catheter material and tip configuration. They have an outer poly-urethane liner and an inner polyamide body. Experimental tests have shown that the positive features (e.g. pushability, kink resistance, gliding, withdrawal) of the Perifix Standard catheter can be maintained. Due to the polyurethane outer layer, the catheter gets softer when reaching body temperature immediately upon insertion. Based on this, it is expected that paraesthesias during catheter injection can be reduced by at least 20%.