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Estimation of Effective Dose 95 (ED95) of Intrathecal Isobaric 2-chloroprocaine (2-CP) Based on the Height (cm) of a Patient Undergoing Ambulatory Knee Arthroscopy

Completed
Conditions
Knee Arthroscopy
Interventions
Registration Number
NCT03882489
Lead Sponsor
Centre Hospitalier Universitaire Saint Pierre
Brief Summary

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

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
120
Inclusion Criteria
  • signed informed consent
  • scheduled outpatient knee arthroscopy
  • between 18 and 80 years old
  • American Society of Anesthesiologists physical status (ASA) < III
  • Height between 150 and 195 cm
Exclusion Criteria
  • cardiac pathology (such as heart failure, aortic stenosis)
  • coagulation disorder (International Normalized Ratio (INR) > 1.3, platelets<80.000/mm3)
  • known allergy to local anaesthetics
  • central and peripheral neuropathies
  • patient's refusal

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Cohort 3 : Height 181-195 cmIsobaric 2-chloroprocaineDose-finding study with 4 subjects per dose and a maximum of 40 patients by cohort. The cohort 3 includes patients whose the height is between 166 and 180 cm. To identify the dose to give for reaching the ED95 (effective dose for 95% subjects), isobaric 2-chloroprocaine will be administrated at the dose initial of 50 mg in the cohort 3 for the first 4 subjects. For the next subjects, the doses to administrate will vary 5 mg (0.5 ml) and will be determined by the Continual Reassessment Method (CRM) according to the observed responses in the previous subjects. Doses will be staggered from 35 to 60 mg for cohort 3.
Cohort 1 : Height 150-165 cmIsobaric 2-chloroprocaineDose-finding study with 4 subjects per dose and a maximum of 40 patients by cohort. The cohort 1 includes patients whose the height is between 150 and 165 cm. To identify the dose to give for reaching the ED95 (effective dose for 95% subjects), isobaric 2-chloroprocaine will be administrated at the dose initial of 40 mg in the cohort 1 for the first 4 subjects. For the next subjects, the doses to administrate will vary 5 mg (0.5 ml) and will be determined by the Continual Reassessment Method (CRM) according to the observed responses in the previous subjects. Doses will be staggered from 25 to 50 mg for cohort 1.
Cohort 2 : Height 166-180 cmIsobaric 2-chloroprocaineDose-finding study with 4 subjects per dose and a maximum of 40 patients by cohort. The cohort 2 includes patients whose the height is between 166 and 180 cm. To identify the dose to give for reaching the ED95 (effective dose for 95% subjects), isobaric 2-chloroprocaine will be administrated at the dose initial of 45 mg in the cohort 2 for the first 4 subjects. For the next subjects, the doses to administrate will vary 5 mg (0.5 ml) and will be determined by the Continual Reassessment Method (CRM) according to the observed responses in the previous subjects. Doses will be staggered from 30 to 55 mg for cohort 2.
Primary Outcome Measures
NameTimeMethod
Success or failure of anesthesiaperioperative

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.

Secondary Outcome Measures
NameTimeMethod
Pain as assessed by Visual Analog Scaleup to 24 hours after surgery

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)

End time of sensory blockUntil complete release of sensory block (up to 5 hours after surgery)

The patient is asked to note the time at which he/she feels that he/she has regained a strictly normal sensitivity

Time to voidup to maximum 5 hours after surgery

The time to obtain the first micturition will be noted.

Maximum level of sensory block assessed as loss of sensation to pinprick, coldUntil complete release of sensory block (up to 5 hours after surgery)

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.

Level of motor block assessed by the Bromage scoreUntil complete release of motor block (up to 5 hours after surgery)

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.

Side-effects (nausea, vomiting)up to 5 hours after surgery

Nausea and vomiting are treated in the PACU and the post operative unit.

Bladder volume before first micturitionup to maximum 5 hours after surgery

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 to eligibility for discharge defined by complete regression of sensory blockup to maximum 5 hours after surgery

Time of discharge of the patient from the hospital.

Trial Locations

Locations (1)

Braine-l'Alleud Hospital

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Braine-l'Alleud,, Belgium

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