In ambulatory surgery, the choice of the local anesthetic used is essential. The ideal local anesthetic must allow a quick installation of the spinal block, a duration of the sensory block adapted to the surgery with a minimum of side effects. These side effects include bradycardia, hypotension and block failure during the intraoperative period; bladder retention, transient neurological disorders during the post-operative period. The achievement of kinetic objectives associated with a reduction in side effects is related to the choice of local anesthetic and the dose administered. However, there are interindividual pharmacokinetic variations that make it difficult to predict the effective dose and the unfortunate occurrence of side effects. In this context, the height of the patient is a criterion involved in the level, the duration of the sensitive motor block and therefore the side effects The local anesthetic of the amino ester family, isobaric 2-chloroprocaine (2-CP) has been successfully used for spinal anesthesia since several decades. With a short duration of action, it is preferred to other anesthetics for the short-term outpatient surgeries. However, the effective dose 95 (ED95) of intrathecal isobaric 2-CP is currently unknown. The purpose of this prospective study is to determine the ED95 of the spinal 2-CP using the continuous re-evaluation method (Continual Reassessment Method) (CRM) based on patient's height
Study Type
OBSERVATIONAL
Enrollment
120
The doses of isobaric 2-chloroprocaine will be administrated intrathecally and will be adjusted according to the observed responses in the previous subjects.
Braine-l'Alleud Hospital
Braine-l'Alleud, Belgium
Success or failure of anesthesia
The anesthesia will be considered as a success if there is an extension of the sensory block to the Th12 dermatome after inflation of the tourniquet, absence of pain during tourniquet inflation, incision and overall surgery. Or the anesthesia will be considered as a failure if there is an absence of extension of the sensory block at the Th12 dermatome, pain at the tourniquet inflation, at the incision, or during surgery.
Time frame: perioperative
Maximum level of sensory block assessed as loss of sensation to pinprick, cold
The level of sensory block will be assessed as loss of sensation to pinprick and cold at 5, 10, 20 and 30 minutes after the intrathecal injection (corresponding to time 0), every 10 minutes in the Post Anesthesia Care Unit (PACU) and every 30 minutes after PACU discharge.
Time frame: Until complete release of sensory block (up to 5 hours after surgery)
Level of motor block assessed by the Bromage score
The level of motor block will be determined at 5, 10, 20 and 30 minutes after intrathecal injection (corresponding to time 0) and every 10 minutes in the post-anesthesia care unit (PACU). The level of motor block will be assessed by using the Bromage Scale.
Time frame: Until complete release of motor block (up to 5 hours after surgery)
Side-effects (nausea, vomiting)
Nausea and vomiting are treated in the PACU and the post operative unit.
Time frame: up to 5 hours after surgery
Pain as assessed by Visual Analog Scale
Pain levels will be determined at tourniquet inflation, incision, every 10 minutes in the post-anesthesia care unit (PACU), every 30 minutes after PACU discharge and 24h after the surgery at home (by phone). Visual Analog pain score (scale = 0 no pain; 10= worst pain imaginable)
Time frame: up to 24 hours after surgery
End time of sensory block
The patient is asked to note the time at which he/she feels that he/she has regained a strictly normal sensitivity
Time frame: Until complete release of sensory block (up to 5 hours after surgery)
Time to void
The time to obtain the first micturition will be noted.
Time frame: up to maximum 5 hours after surgery
Bladder volume before first micturition
An evacuating bladder catheterization is performed when a bladder volume greater than 600 mL, confirmed by a Bladderscan device, is associated with the following signs and/or symptoms: hypogastric pain, anuria or overflow urination.
Time frame: up to maximum 5 hours after surgery
Time to eligibility for discharge defined by complete regression of sensory block
Time of discharge of the patient from the hospital.
Time frame: up to maximum 5 hours after surgery
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.