Spinal Anesthesia, Hemodynamic Changes, Patient Positions, Bupivacaine
Conditions
Keywords
Spinal Anesthesia, Bupivacaine, Patient Positioning, hemodynamic changes
Brief summary
This study compares different combinations of local anesthetic doses and patient positions during spinal anesthesia for urogenital surgery. Spinal anesthesia is a common and safe technique where medication is injected into the lower back to numb the body during surgery. The study will test two different doses of bupivacaine (a numbing medication): a lower dose (8 mg) and a standard dose (12 mg). It will also test two different patient positions after the spinal injection: lying flat (neutral position) and lying with the head slightly lower than the feet (Trendelenburg position). Participants will be randomly assigned to one of four groups: * Group 1: Lower dose + lying flat * Group 2: Lower dose + head-down position * Group 3: Standard dose + lying flat * Group 4: Standard dose + head-down position The study will measure how well the anesthesia works, how high the numbness spreads in the body, and how it affects blood pressure and heart rate. The goal is to find the best combination of dose and position that provides good anesthesia while keeping blood pressure stable. This research may help doctors choose the safest and most effective anesthesia approach for each patient based on their individual needs.
Interventions
8 mg or 12 mg 0.5% hyperbaric bupivacaine administered intrathecally via spinal anesthesia at L3-4 or L4-5 interspace.
Sponsors
University of Health Sciences Balikesir Hospital Eduation and Research
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
The outcomes assessor evaluating sensory block levels, motor block, and recording data will be blinded to group allocation. The anesthesiologist performing the spinal anesthesia and positioning cannot be blinded due to the nature of the intervention.
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* Age 18-70 years * American Society of Anesthesiologists (ASA) physical status classification I-II * Scheduled for elective urogenital surgery * Suitable candidate for spinal anesthesia * Able to read, understand, and provide written informed consent * Body Mass Index (BMI) less than 35 kg/m² * Willing to participate in the study
Exclusion criteria
* Contraindications to spinal anesthesia (coagulopathy, infection at injection site, patient refusal) * History of neurological disease * Spinal deformity or previous spinal surgery * History of allergic reaction to local anesthetics (amide-type) * ASA physical status classification III or higher * Emergency surgery * Pregnancy * Psychiatric illness preventing effective communication * Refusal to participate in the study * Unable to understand or provide informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Maximum Sensory Block Level | From injection to 30 minutes post-spinal anesthesia | The highest dermatomal level of sensory blockade achieved, assessed using pin-prick test (sharp/dull discrimination). Measured as the specific dermatome level (e.g., T4, T6, T8). |
| Incidence of Hypotension | From spinal injection through end of surgery | Proportion of participants experiencing hypotension, defined as mean arterial pressure (MAP) decrease ≥20% from baseline |
| Sensory Block Onset Time | From spinal injection through end of surgery | Time required to achieve T10 dermatomal sensory block level, measured from completion of intrathecal injection to confirmation of T10 level by pin-prick test. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Motor Block Degree | From spinal injection through end of surgery | Degree of motor blockade assessed using modified Bromage scale (0=no motor block, able to raise extended leg; 1=unable to raise extended leg, able to flex knee; 2=unable to flex knee, able to flex ankle; 3=complete motor block, unable to move). |
| Surgical Adequacy | Throughout surgery | Proportion of participants with adequate anesthesia for surgical procedure completion, assessed as adequate (surgery completed without supplemental analgesia/sedation) or inadequate (requiring supplemental intervention). |
| Incidence of Bradycardia | From spinal injection through end of surgery | Proportion of participants experiencing bradycardia, defined as heart rate \<50 beats per minute requiring treatment. |
| Incidence of Nausea and Vomiting | From spinal injection through end of surgery | Proportion of participants experiencing nausea and/or vomiting during the intraoperative and immediate postoperative period. |
Contacts
CONTACTHasan Duman, M.D.
Outcome results
None listed