Crystallization of LA and Adjuvant Mixtures in Cerebrospinal Fluid

NCT07442929 | Recruiting

• 1 other identifier: Crystal_Liquor
• Study Type: observational
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Hydrocephalus

Keywords

local anesthetics;; local anesthetic mixtures; cerebrospinal fluid; in vitro; crystallization; pH; adjuvants

Outcome Measures

Primary Outcomes (1)

• Grade of Crystallisation

  For the grading of detectable precipitations, a scale from 0 (no signs of precipitation / single particulates \< 10 μm) to 5 (heavy polymorphic crystallization: \> 100 solid bodies \> 10 μm, and \> 1 solid body \> 50 μm or \> 1 solid body \> 100 μm) will be used.

  1 hour

Secondary Outcomes (2)

• pH value and of CSF and CSF LA mixtures

  1 hour

• pCO2 of CSF and CSF LA mixtures

  1 hour

Study Arms (1)

Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture

Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

patients with normal pressure hydrocephalus scheduled for elective lumbar puncture.

You may qualify if:

• Patients with normal pressure hydrocephalus scheduled for elective lumbar puncture.

You may not qualify if:

• Age \< 18 years

Sponsors & Collaborators

• Medical University Innsbruck: lead

Study Sites (1)

Medical University Innsbruck

Innsbruck, Tyrol, 6020, Austria

RECRUITING

Related Publications (1)

• 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 BACKGROUND

MeSH Terms

Conditions

Hydrocephalus

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Study Officials

• Elisabeth Gasteiger, MD PhD

  Medical Unicersity Innsbruck

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Elisabeth Gasteiger, MD PhD

CONTACT

+43-512-504-22400; elisabeth.gasteiger@tirol-kliniken.at

Lukas Gasteiger, MD PD

CONTACT

+43-512-504-22400; lukas.gasteiger@tirol-kliniken.at

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 18, 2025
• First Posted: March 2, 2026
• Study Start: September 1, 2025
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: March 2, 2026

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: ANALYTIC CODE
• Time Frame: Data will only be shared on a reasonable request.
• Access Criteria: Data will only be shared on a reasonable request.

Locations

AU (1)