Chloroprocaine for Inguinal Herniorrhaphy

A standard CSE procedure will be conducted in which the patient is placed in an upright sitting position on the side of the operation table and a epidural Tuohy needle 18G will be inserted into L3-L4 interspace via a loss-of-resistance technique. The dura will be punctured using a 27-gauge pencil-point spinal needle and a certain dose of chloroprocaine 1% will be given. After the spinal needle is withdrawn, an epidural catheter will be placed and the epidural needle will be withdrawn. After fixation of catheter the patient will be placed in a supine position.

The first spinal dose of chloroprocaine 1% to start with is 50mg. This dose has been successfully used for spinal anesthesia in hernia repair outpatients to reach an adequate analgesia. Each time there will be added 2,5 microgram of sufentanil for prolongation of the analgesia. The testing interval is 2 mg.

• Chloroprocaine 1% Injectable Solution (Drug), also known as chloroprocaine 3%: standard CSE procedure in outpatients for inguinal hernia. The first spinal dose of chloroprocaine 1% to start with is 50mg. This dose has been successfully used for spinal anesthesia in hernia repair outpatients to reach an adequate analgesia. 2,5 microgram of sufentanil will be added for prolongation of the analgesia. The testing interval is 2 mg. Efficacy of the analgesia will be evaluated: Successful : sensory block at or above T6 dermatome bilateral at the beginning of surgery without additional analgesia during surgery. Unsuccessful: sensory block under T6 dermatome bilateral and/or VAPS is more than 10 mm at the beginning of surgery what necessitates additional epidurals analgesia. Patients who indicate an ineffective result will receive a rescue treatment by the administration of 5 ml chloroprocaine 3% epidural every 5 minutes with maximum of 30ml. When CSE fails, general anesthesia will be performed.

Primary outcomes

• The dose of chloroprocaine 1% needed for the individual patient for a sensory anesthesia block at or above the T6 dermatome [start of surgery]: MLAD of chloroprocaine 1% with 2,5 mcg of sufentanil needed for the individual patient required for a sensory anesthesia at or above the T6 dermatome at the beginning of surgery with no additional epidural anesthesia required during surgery

Secondary outcomes

• Peak block height [during surgery]: highest sensible block
• Time for regression of two segments [during surgery]: Time for regression of two segments
• Ambulation time [From starting hour of spinal anesthesia to hour of first ambulation after the end of surgery measured up to 6 hours after surgery]: motor recovery
• Time to micturition [From starting hour of spinal anesthesia to hour of first micturition after the end of surgery measured up to 6 hours after surgery]: Time to micturition
• Incidence of side effects (perioperative hypotension, respiratory depression, neurologic deficits) [perioperative]: Incidence of side effects (perioperative hypotension, respiratory depression, neurologic deficits)
• Time to discharge [From starting hour of spinal anesthesia to hour of discharge from hospital measured up to 6 hours after surgery]: Time to discharge
• Patient satisfaction with anesthesia method: questionnaire [postoperatively,at moment of hospital discharge measured up to 6 hours after surgery]: Patient satisfaction with simple questionnair (highly satisfied, satisfied, unsatisfied)

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Outpatients for unilateral inguinal hernia repair
* ASA I - II - III

Exclusion Criteria:

* hypersensitivity to amino-ester local anesthetics, para-aminobenzoic acid or sufentanil
* contraindications to spinal or epidural anesthesia
* bilateral inguinal herniorrhaphy
* extremes of height and weight (BMI 20 or 35 kg/m2, height 150 cm or 185 cm)

• Aliaksandra Parashchanka, MD, Principal investigator, stafmember department of Anesthesiology