Crystallization of LA and Adjuvant Mixtures in Cerebrospinal Fluid
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- This is an observational study: the protocol does not assign a study treatment.
- Who it may be relevant to
- Registry conditions: Hydrocephalus. Basic parameters: from 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Austria
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Crystallization of Local Anesthetic and Adjuvant Mixtures in Cerebrospinal Fluid as a Model for Interstitial Space - a Semiquantitative in Vitro Trial
Overview
Different mixtures of local anesthetics or local anesthetics with adjuvants that are known to precipitate in vitro are tested in human cerebrospinal fluid (CSF). CSF is gained from patients with normal pressure hydrocephalus scheduled for elective lumbar puncture. Patients signed an ICF for leftover samples. CSF will be assessed for pH values at different timepoints (t0-t3; 0 to 60 minutes). In a second step six commonly used mixtures of LA with LA or LAs with adjuvants will be mixed using the following mixture ratios: ropivacaine 0.75% + lidocaine 2% (ratio 1:1), ropivacaine 0,75% + mepivacaine 2% (ratio 1:1), ropivacaine 0.75% + chloroprocaine 2% (ratio 1:1), lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:0.1), ropivacaine 0.75% + lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:1:0.1) and ropivacaine 0.75% + dexamethasone (1.5:1). The used mixture ratios are inspired by commonly mixtures described in the current literature and have been proven to precipitate in vitro. For every mixture, a Grade of Crystallisation will be determined at baseline without CSF and then at t0 (immediately) to t3 (60 minutes) every 15 minutes.
Detailed description
Different mixtures of local anesthetics or local anesthetics with adjuvants that are known to precipitate in vitro are tested in human cerebrospinal fluid (CSF). CSF is gained from patients with normal pressure hydrocephalus scheduled for elective lumbar puncture. Patients signed an ICF for leftover samples.
CSF will be assessed for pH values at different timepoints (t0-t3; 0 to 60 minutes).
In a second step six commonly used mixtures of LA with LA or LAs with adjuvants will be mixed using the following mixture ratios: ropivacaine 0.75% + lidocaine 2% (ratio 1:1), ropivacaine 0,75% + mepivacaine 2% (ratio 1:1), ropivacaine 0.75% + chloroprocaine 2% (ratio 1:1), lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:0.1), ropivacaine 0.75% + lidocaine 2% + sodium bicarbonate 8.4% (ratio 1:1:0.1) and ropivacaine 0.75% + dexamethasone (1.5:1). The used mixture ratios are inspired by commonly mixtures described in the current literature and have been proven to precipitate in vitro. For every mixture, a Grade of Crystallisation will be determined at baseline without CSF and then at t0 (immediately) to t3 (60 minutes) every 15 minutes.
Primary outcome measures
- Grade of Crystallisation [Time frame: 1 hour]
Secondary outcome measures (2)
- pH value and of CSF and CSF LA mixtures [Time frame: 1 hour]
- pCO2 of CSF and CSF LA mixtures [Time frame: 1 hour]
Eligibility criteria
Inclusion criteria
- Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture.
Exclusion criteria
- Age < 18 years
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Other
Study locations
Austria · 1 center
- Medical University Innsbruck — Innsbruck
Publications
- Hoerner E, Stundner O, Putz G, Steinfeldt T, Mathis S, Gasteiger L. Crystallization of ropivacaine and bupivacaine when mixed with different adjuvants: a semiquantitative light microscopy analysis. Reg Anesth Pain Med. 2022 Jun 23:rapm-2022-103610. doi: 10.1136/rapm-2022-103610. Online ahead of print. PMID 35738668
Identifiers
NCT: NCT07442929 · Crystal_Liquor