Staphylococcus Aureus Bacterial Contamination
Conditions
Keywords
Levobupivacaine, Antibacterial effect, Patient Controlled Analgesia (PCA), Fentanyl, Scanning Electron Microscope (SEM), Staphylococcus aureus
Brief summary
This experimental in vitro study aimed to investigate the antibacterial effect of levobupivacaine on Staphylococcus aureus in a patient-controlled analgesia (PCA) model at concentrations commonly used for postoperative pain treatment (0.125%) and painless labour (0.0625%). The antibacterial activity was evaluated using colony count reduction and supported by Scanning Electron Microscope (SEM) imaging.
Detailed description
Study solutions were prepared as 100 mL each. Four groups were designed: * Group 1: 0.125% levobupivacaine + 4 mL fentanyl (200 mcg) * Group 2: 0.0625% levobupivacaine + 4 mL fentanyl (200 mcg) * Group 3: 4 mL fentanyl (200 mcg) * Group 4: 99 mL saline (control) Each group received 1 mL of Staphylococcus aureus 0.5 McF (1.5×10⁸ cfu/mL). All samples were infused through a Portex bacterial filter at 4 mL/h for 24 hours using PCA devices. Samples collected from bottles, filter inlets, and outlets were cultivated on Blood Agar. Colony counts were compared statistically using the Kruskal-Wallis and Mann-Whitney U tests (p\<0.05).
Interventions
DRUGLevobupivacaine
Levobupivacaine is a local anesthetic used at concentrations of 0.125% and 0.0625% to evaluate its antibacterial effect against Staphylococcus aureus in an in vitro PCA model.
DRUGFentanyl
Fentanyl is an opioid analgesic used at a concentration of 200 mcg/4 mL, either alone or in combination with levobupivacaine, to assess potential contribution to antibacterial activity.
OTHERSaline
Sterile saline solution (99 mL) used as the control group to compare antibacterial activity in the PCA infusion model.
Sponsors
Dokuz Eylul University
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Masking description
No masking was performed. The study was conducted as an open-label in vitro experimental model.
Intervention model description
Four independent groups were prepared using levobupivacaine and fentanyl at different concentrations and compared in parallel under in vitro laboratory conditions.
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* Laboratory study using Staphylococcus aureus bacterial cultures. * Samples exposed to different concentrations of levobupivacaine and fentanyl solutions. * Controlled laboratory environment (Dokuz Eylül University, Microbiology Laboratory).
Exclusion criteria
* No human participants included. * No animal models used. * Studies outside the defined experimental conditions were excluded.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Reduction in Staphylococcus aureus Colony Count | 24 hours | Quantitative measurement of the antibacterial effect of levobupivacaine and fentanyl by counting Staphylococcus aureus colonies grown on Blood Agar after 24-hour PCA infusion at different concentrations. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Morphological Changes of Staphylococcus aureus under SEM | 48 | Evaluation of ultrastructural changes in Staphylococcus aureus cells after exposure to levobupivacaine and fentanyl using Scanning Electron Microscope (SEM) imaging. |
Outcome results
None listed