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

Centre Hospitalier Universitaire Saint Pierre

Status: Completed

Conditions: Knee Arthroscopy

Treatments: Drug: Isobaric 2-chloroprocaine

Study type: Observational

Funder types: Other

Identifiers

NCT03882489

B076201836762

Details and patient eligibility

About

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

Enrollment: 120 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

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

Trial design

120 participants in 3 patient groups

Cohort 1 : Height 150-165 cm

Description:

Dose-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.

Treatment:

Drug: Isobaric 2-chloroprocaine

Cohort 2 : Height 166-180 cm

Description:

Dose-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.

Treatment:

Drug: Isobaric 2-chloroprocaine

Cohort 3 : Height 181-195 cm

Description:

Dose-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.

Treatment:

Drug: Isobaric 2-chloroprocaine