Evaluate Requirements of 2% Prilocaine in MR-UF Prostate Biopsy
Conditions
Keywords
ED50, hyperbaric prilocaine, ultrasound fusion guided prostate biopsy
Brief summary
The aim of the present study was to determine the ED50 and ED90 of intrathecal hyperbaric 2% prilocaine (HP) for patients undergoing ambulatory prostate biopsy via magnetic resonance imaging (MRI)/ultrasound fusion.
Detailed description
Prostate biopsy to diagnose or exclude cancer is currently performed an estimated one million times annually worldwide. In this method, the operator images the prostate using ultrasound, as performed for the past several decades; while thus viewing the prostate, the MRI of that prostate, which is performed beforehand and stored in the device, is fused with real-time ultrasound using a digital overlay, allowing the target(s), previously delineated by a radiologist, to be brought into the aiming mechanism of the ultrasound machine. The fusion results in creation of a three-dimensional reconstruction of the prostate, and on the reconstructed model, the aiming and tracking of biopsy sites occurs. This method needs for sedation/general/ spinal anesthesia because of patient discomfort with the transperineal approach of the biopsy needle passing through the perineum. Even though the MRI/ultrasound fusión prostate biopsy is widespread used, the anaesthetic techniques for this procedure are not standardised. Hyperbaric prilocaine is an amide-type local anesthetic widely used in short surgical procedures showing its efficacy for outpatient surgery. The proposed intrathecal doses of prilocaine for various surgical procedures range from 10 to 80 mg. Thus, even though the drug is in clinical use, optimal doses of HP required for specific types of surgery warrant further refinement. The aim of the present study was to determine the ED50 and ED90 of intrathecal HP for patients undergoing undergoing ambulatory MRI/ultrasound fusión prostate biopsy.
Interventions
With the patient in the sitting position, spinal anesthesia was performed using the midline approach at the L3-L4; L4-L5 interspace with a spinal needle. The dose of HP that a patient received was determined by the previous patient's response. If successful anesthesia was obtained, the next patient's dose was decreased. The first patient will receive a dose of 20 mg. The dose decrement/increment for each subsequent patient will be set at 2 mg. A nurse blinded to the dose, will assess the sensitive level achieved with each block. Furthermore, all patients will be unaware of the injected dose of HP. For purposes of the study, anesthesia was considered successful when there was complete loss of pinprick and cold sensation at the L1 dermatome. Values of ED 50 will be determined by calculating the midpoint concentration after at least 8 crossover points sufficient/insufficient anesthesia will be obtained. A single measurement will be obtained from each patient.
Sponsors
Study design
Masking description
The nurse blinded to the dose, was absent during the procedure and assessed each block. Furthermore, all patients were unaware of the injected dose of HP.
Intervention model description
To evaluate the ED50 and ED90 of intrathecal HP for patients undergoing undergoing ambulatory MRI/ultrasound fusión prostate biopsy.
Eligibility
Inclusion criteria
ASA II-III patients Aged 18-85 years Prostate fusion biopsy procedure Scheduled to ambulatory surgery Signed informed consent
Exclusion criteria
* Standard contraindications to neuraxial blockade, coagulopathy, site infection, neurological impairment, known allergy to local anesthetics. Refusal of the patient to participate in the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| ED50 of intrathecal hyperbaric 2% prilocaine in transperineal magnetic resonance imaging-transrectal ultrasound fusion guided biopsy | From the baseline, previous to prilocaine adminstration until the end of the prostate biopsy procedure. 30 minutes | to determine the ED50 and ED90 of intrathecal HP for patients undergoing undergoing ambulatory MRI/ultrasound fusión prostate biopsy. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| To analyze the hemodynamic response during surgery | From the baseline previous to prilocaine adminstration until the end of the prostate biopsy. 30 minutes | To evaluate the incidence of hypertension, hypotension, bradycardia or tachycardia during the prostate biopsy procedure. |
| acute urinary retention | From the baseline previous to prilocaine adminstration until the first 24 hours after the prostate biopsy procedure | Evaluate the incidence of urinary retention |
| length of stay in the facility | From the baseline previous to prilocaine adminstration until the patient meets discharge criteria, defined by complete regression of sensory block. | Time to eligibility for home discharge, |
| incidence of unplanned admissions | From the baseline previous to prilocaine adminstration until the first 24 hours after the prostate biopsy procedure | To know the incidence of patients who cannot be discharged from the unit. |
Countries
Spain