Anesthesia, LocalNCT06166394
Spinal Hypobaric Local Anesthetic Study
An observational study of Anesthesia, Local, run by University Health Network, Toronto at 1 site in Canada.
Trial summary
The length of hospital stay after total hip and knee arthroplasty is determined based on the successful mobilization of the patients post surgery. Fast track pathways involving early mobilization and discharge of the patient on the same day of surgery, shortens the hospital stay and reduces the risk of adverse… Read more about this study
- Who is it for?
- Ages 20 years and older
- Conditions the study is for
- Anesthesia, Local
- What is being tested?
- Spinal hypobaric Mepivacaine Local Anesthetic Injection and Spinal hypobaric Bupivacaine Local Anesthetic Injection
- Type of treatment
- Injection or infusion
- How many people
- 60 participants
- Where
- 1 siteCanada
- Study dates
- 9 Jun 2023to 24 May 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: All day surgery and in-patients who are scheduled to undergo elective unilateral total hip or knee arthroplasty under spinal anesthesia at Toronto Western Hospital
Who may be able to join
- Patients undergoing elective unilateral total hip or knee arthroplasty under spinal anesthesia at Toronto Western Hospital
- American Society of Anesthesiologists physical status class (ASA-PS) 1-3
- Aged ≥ 20 years
Who cannot join
- Refusal to participate
- Inability to communicate due to language barrier or cognitive impairment
- Height < 150 cm or > 200 cm
- Weight < 40 kg or >130 kg
- Contraindication or allergy to amide-type local anesthetic
- Contraindication to spinal anesthesia (e.g., infection at the injection site, existing coagulopathy)
Show all 10Show fewer
- Spinal anesthesia performed in the operating room rather than the block room (which will preclude adequate testing)
- Spinal anesthesia that includes administration of intrathecal opioids (e.g., morphine, fentanyl),so as to avoid unanticipated alterations in block quality or solution baricities.
- Pre-existing sensory or motor impairment in the lower extremities
- -
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Pharmacodynamic Profile of Intrathecal Hypobaric Local Anesthetics. An Observational Study
The length of hospital stay after total hip and knee arthroplasty is determined based on the successful mobilization of the patients post surgery. Fast track pathways involving early mobilization and discharge of the patient on the same day of surgery, shortens the hospital stay and reduces the risk of adverse effects. The long acting LA (bupivacaine) is most commonly used in spinal anesthesia for arthroplasty surgeries and is associated with a prolonged motor and sensory block. In contrast, hypobaric bupivacaine and hypobaric mepivacaine helps in achieving the desired block level with smaller dosage and shorter onset time and faster recovery when compared to long acting local anesthetics. The aim of the study is to observe the effects of hypobaric local anesthetics ( bupivacaine and mepivacaine ) in patients undergoing unilateral total hip or knee arthroplasty in terms of time to onset and time to recovery of the block and also its effect on hemodynamic stability and time to mobilization after surgery. This study will allow the investigators to recommend optimal dosing strategies that in turn will help in faster recovery from spinal anesthesia and early mobilization thereby reducing harmful outcomes.
Read the detailed description
Fast-track pathways involving same day mobilization and hospital discharge for total hip and knee arthroplasty are increasingly popular in modern orthopedic practice. Numerous reports have demonstrated the feasibility of this approach.
The choice of local anesthetic (LA) drug and dose administered in spinal anesthesia is determined by several considerations including the desired block height (the upper limit of sensory loss and surgical anesthesia that is achieved) and block duration. Block height and duration should be adequate for the surgery in question, but should ideally not be excessive, as they can lead to adverse effects including sympathetic blockade and hypotension, urinary retention, and delayed recovery of motor function in the lower limbs. The long-acting amide LA, bupivacaine, is most commonly used in this setting at Toronto Western Hospital (TWH) and elsewhere in the world. It is, however, associated with a prolonged motor and sensory recovery (4-6 hours). An alternative strategy to achieve adequate block height without using excessive doses of LA is to administer a hypobaric solution of bupivacaine or mepivacaine; this has been trialed with success at TWH and is now used routinely by staff anesthesiologists. Nevertheless, most of the investigator's knowledge regarding hypobaric LA solutions in spinal anesthesia comes from studies that are more than two decades old. There are no studies on mepivacaine, and neither hypobaric bupivacaine nor mepivacaine have been investigated in the context of fast-track total hip and knee arthroplasty pathways. In this context, the ideal LA solution used for spinal anesthesia should provide a consistent and fast onset time to achieve the required surgical anesthesia while the sensory and motor block should resolve as soon as possible after surgery. The investigators believe that hypobaric bupivacaine and hypobaric mepivacaine may satisfy these criteria and hence, the investigators aim to study their pharmacodynamics.
- Conditions
- Anesthesia, Local
- Being tested
- Spinal hypobaric Mepivacaine Local Anesthetic Injection, Spinal hypobaric Bupivacaine Local Anesthetic Injection
- Keywords
- Spinal Hypobaric LA, Bupivacaine, Mepivacaine
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Spinal hypobaric Mepivacaine Local Anesthetic InjectionDrug
Also called Carbocaine
- Administration of a hypobaric spinal mixture for Day-Surgery patients: 3.4ml of 1.5% mepivacaine created by 3ml 2% mepivacaine with 1ml sterile water, and then discarding 0.6ml
Spinal hypobaric Bupivacaine Local Anesthetic InjectionDrug
Also called Marcaine
Administration of a hypobaric spinal mixture for In-patients:
3ml of 0.33% bupivacaine created by 2ml 0.5% bupivacaine with 1ml sterile water
| Study group | Role | What they receive |
|---|---|---|
| Mepivacaine | Day surgery patients(30 patients); For these patients- Administration of a spinal hypobaric mepivacaine injection Receives: Drug: Spinal hypobaric Mepivacaine Local Anesthetic Injection | |
| Bupivacaine | In-patients(30 patients): For these patients- Administration of a spinal hypobaric bupivacaine injection Receives: Drug: Spinal hypobaric Bupivacaine Local Anesthetic Injection |
What is being measured
The primary outcome is the main question the study is designed to answer.
1. Time to reach the most cephalad/cranial sensory block level (onset time of spinal anesthesia on the surgical side).
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
Time to reach sensory block level of L1 or higher (adequate level of anesthesia for knee surgery) on the surgical side
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
Time to reach sensory block level T10 or higher (adequate level of anesthesia for hip surgery) on the surgical side
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
The most cephalad/cranial sensory block level
Sensory block will be assessed every 5 mins during the first 30 mins after spinal injection. A pinprick test using an 18G (Gauge) blunt-tipped needle (BD Blunt Fill needle) will be performed on non-dependent and dependent sides to detect sensory loss over the torso and lower limbs.
Measured: Assessed over the duration of time period till the patient is discharged.
Time to achieve complete motor block on the modified Bromage scale
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
Secondary outcomes (7)
Time to regression of the sensory block to the L2 dermatome on both lower limbs.
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
Time to full motor recovery on the modified Bromage scale
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
Hemodynamic stability after the spinal injection
Will be assessed by the measurement of vitals
Measured: Assessed over the duration of time period till the patient is discharged.
Time to ambulation
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Measured: Assessed over the duration of time period till the patient is discharged.
Patient satisfaction score
Assessed by a five-point Likert scale provided to the patient
Measured: Assessed before the patient is discharged.
Surgeon's perception of quality of anesthesia
Assessed by a three-point Likert scale provided to the surgeon
Measured: Assessed after the end of surgery.
Rate of successful spinal anesthesia
Will be determined as successful when there will be no need to convert to general anesthesia or administer supplemental opioids or local infiltration in the operating room.
Measured: Assessed after the spinal block till the end of surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Dec 2023
- Study start9 Jun 2023
- Primary completion17 Oct 2023
- Study completion24 May 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Anesthesia, LocalStudies of the same condition, open and under way.
- More trials run by University Health Network, TorontoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 60 participants (actual)
Sponsor and investigators
- Lead sponsor
- University Health Network, Toronto
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Ki Jinn Chin, MD,FRCPC, Principal investigator, UHN
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06166394
- Sponsor's protocol ID
- 22-5558
- Other IDs
- v04Nov2022
- Status last verified
- Mar 2025
- First submitted
- 4 Dec 2023
- Last updated
- 28 Mar 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Tan JMH, Wang W, Yoshida T, Abdullah S, Chowdhury J, Chin KJ. The anesthetic and recovery profiles of low-dose hypobaric mepivacaine and bupivacaine for spinal anesthesia in total hip and knee arthroplasty: a prospective observational study. Can J Anaesth. 2025 Feb;72(2):242-253. doi: 10.1007/s12630-024-02887-y. Epub 2024 Dec 10.
PubMed 39653970
Study at a glance
From the registry record, last updated by the sponsor on 28 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Pharmacodynamic Profile of Intrathecal Hypobaric Local Anesthetics. An Observational Study
- ClinicalTrials.gov ID
- NCT06166394
- Acronym / sponsor ID
- 22-5558
- Conditions
- Anesthesia, Local
- Keywords
- Spinal Hypobaric LA, Bupivacaine, Mepivacaine
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 60 participants (actual)
- Lead sponsor
- University Health Network, TorontoUniversity, hospital or other
- Study start
- 9 Jun 2023 (actual)
- Primary completion
- 17 Oct 2023 (actual)
- Study completion
- 24 May 2024 (actual)
- First posted
- 12 Dec 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The length of hospital stay after total hip and knee arthroplasty is determined based on the successful mobilization of the patients post surgery. Fast track pathways involving early mobilization and discharge of the patient on the same day of surgery, shortens the hospital stay and reduces the risk of adverse effects. The long acting LA (bupivacaine) is most commonly used in spinal anesthesia for arthroplasty surgeries and is associated with a prolonged motor and sensory block. In contrast, hypobaric bupivacaine and hypobaric mepivacaine helps in achieving the desired block level with smaller dosage and shorter onset time and faster recovery when compared to long acting local anesthetics. The aim of the study is to observe the effects of hypobaric local anesthetics ( bupivacaine and mepivacaine ) in patients undergoing unilateral total hip or knee arthroplasty in terms of time to onset and time to recovery of the block and also its effect on hemodynamic stability and time to mobilization after surgery. This study will allow the investigators to recommend optimal dosing strategies that in turn will help in faster recovery from spinal anesthesia and early mobilization thereby reducing harmful outcomes.
Detailed description
Fast-track pathways involving same day mobilization and hospital discharge for total hip and knee arthroplasty are increasingly popular in modern orthopedic practice. Numerous reports have demonstrated the feasibility of this approach.
The choice of local anesthetic (LA) drug and dose administered in spinal anesthesia is determined by several considerations including the desired block height (the upper limit of sensory loss and surgical anesthesia that is achieved) and block duration. Block height and duration should be adequate for the surgery in question, but should ideally not be excessive, as they can lead to adverse effects including sympathetic blockade and hypotension, urinary retention, and delayed recovery of motor function in the lower limbs. The long-acting amide LA, bupivacaine, is most commonly used in this setting at Toronto Western Hospital (TWH) and elsewhere in the world. It is, however, associated with a prolonged motor and sensory recovery (4-6 hours). An alternative strategy to achieve adequate block height without using excessive doses of LA is to administer a hypobaric solution of bupivacaine or mepivacaine; this has been trialed with success at TWH and is now used routinely by staff anesthesiologists. Nevertheless, most of the investigator's knowledge regarding hypobaric LA solutions in spinal anesthesia comes from studies that are more than two decades old. There are no studies on mepivacaine, and neither hypobaric bupivacaine nor mepivacaine have been investigated in the context of fast-track total hip and knee arthroplasty pathways. In this context, the ideal LA solution used for spinal anesthesia should provide a consistent and fast onset time to achieve the required surgical anesthesia while the sensory and motor block should resolve as soon as possible after surgery. The investigators believe that hypobaric bupivacaine and hypobaric mepivacaine may satisfy these criteria and hence, the investigators aim to study their pharmacodynamics.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Mepivacaine | – | Drug: Spinal hypobaric Mepivacaine Local Anesthetic InjectionDay surgery patients(30 patients); For these patients- Administration of a spinal hypobaric mepivacaine injection |
| Bupivacaine | – | Drug: Spinal hypobaric Bupivacaine Local Anesthetic InjectionIn-patients(30 patients): For these patients- Administration of a spinal hypobaric bupivacaine injection |
Who may qualify
- Ages
- 20 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- All day surgery and in-patients who are scheduled to undergo elective unilateral total hip or knee arthroplasty under spinal anesthesia at Toronto Western Hospital
Key inclusion criteria (3 listed)
- Patients undergoing elective unilateral total hip or knee arthroplasty under spinal anesthesia at Toronto Western Hospital
- American Society of Anesthesiologists physical status class (ASA-PS) 1-3
- Aged ≥ 20 years
Key exclusion criteria (10 listed)
- Refusal to participate
- Inability to communicate due to language barrier or cognitive impairment
- Height < 150 cm or > 200 cm
- Weight < 40 kg or >130 kg
- Contraindication or allergy to amide-type local anesthetic
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Spinal hypobaric Mepivacaine Local Anesthetic InjectionAlso: Carbocaine• Administration of a hypobaric spinal mixture for Day-Surgery patients: 3.4ml of 1.5% mepivacaine created by 3ml 2% mepivacaine with 1ml sterile water, and then discarding 0.6ml | Drug | Mepivacaine |
| Spinal hypobaric Bupivacaine Local Anesthetic InjectionAlso: MarcaineAdministration of a hypobaric spinal mixture for In-patients: 3ml of 0.33% bupivacaine created by 2ml 0.5% bupivacaine with 1ml sterile water | Drug | Bupivacaine |
Primary outcome
1. Time to reach the most cephalad/cranial sensory block level (onset time of spinal anesthesia on the surgical side).
Time frame: Assessed over the duration of time period till the patient is discharged.
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Time to reach sensory block level of L1 or higher (adequate level of anesthesia for knee surgery) on the surgical side
Time frame: Assessed over the duration of time period till the patient is discharged.
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
Time to reach sensory block level T10 or higher (adequate level of anesthesia for hip surgery) on the surgical side
Time frame: Assessed over the duration of time period till the patient is discharged.
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
The most cephalad/cranial sensory block level
Time frame: Assessed over the duration of time period till the patient is discharged.
Sensory block will be assessed every 5 mins during the first 30 mins after spinal injection. A pinprick test using an 18G (Gauge) blunt-tipped needle (BD Blunt Fill needle) will be performed on non-dependent and dependent sides to detect sensory loss over the torso and lower limbs.
Time to achieve complete motor block on the modified Bromage scale
Time frame: Assessed over the duration of time period till the patient is discharged.
Time to onset is a continuous variable and therefore will be expressed as mean ± standard deviation.
7 secondary outcomes
Time to regression of the sensory block to the L2 dermatome on both lower limbs.
Time frame: Assessed over the duration of time period till the patient is discharged.
Time to full motor recovery on the modified Bromage scale
Time frame: Assessed over the duration of time period till the patient is discharged.
Hemodynamic stability after the spinal injection
Time frame: Assessed over the duration of time period till the patient is discharged.
Time to ambulation
Time frame: Assessed over the duration of time period till the patient is discharged.
Patient satisfaction score
Time frame: Assessed before the patient is discharged.
Surgeon's perception of quality of anesthesia
Time frame: Assessed after the end of surgery.
Rate of successful spinal anesthesia
Time frame: Assessed after the spinal block till the end of surgery
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Mar 2025.
- Derived from this study: PubMed 39653970Tan JMH, Wang W, Yoshida T, Abdullah S, Chowdhury J, Chin KJ. The anesthetic and recovery profiles of low-dose hypobaric mepivacaine and bupivacaine for spinal anesthesia in total hip and knee arthroplasty: a prospective observational study. Can J Anaesth. 2025 Feb;72(2):242-253. doi: 10.1007/s12630-024-02887-y. Epub 2024 Dec 10.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Ki Jinn Chin, MD,FRCPC principal investigator
UHN
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Anesthesia, Local, run by University Health Network, Toronto at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 28 Mar 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
1. Time to reach the most cephalad/cranial sensory block level (onset time of spinal anesthesia on the surgical side). (time frame: Assessed over the duration of time period till the patient is discharged.). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06166394, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Mar 2025; AzTrials last refreshed its copy on 4 Nov 2026.