Postoperative Pain
Conditions
Keywords
Postoperative Pain, Thoracotomy, Acute Pain, Thoracic Surgery, Regional Anesthesia
Brief summary
This is a randomized, assessor-blinded, non-inferiority clinical trial comparing continuous thoracic paravertebral block (BPV) versus continuous thoracic epidural block (BPD) for postoperative pain control in adult patients undergoing elective open thoracotomy with one-lung ventilation. The primary outcome is the mean pain intensity at rest assessed by the Numeric Verbal Scale (NVS 0-10) during the first 48 hours after surgery. A total of 80 participants will be randomized 1:1 at Hospital de Clínicas de Porto Alegre, Brazil. The study aims to determine whether BPV provides non-inferior analgesia compared to BPD, with a potential advantage of less hemodynamic interference and better postoperative mobilization.
Detailed description
This is a randomized, assessor-blinded, non-inferiority clinical trial conducted at Hospital de Clínicas de Porto Alegre, Brazil, in adult patients undergoing elective open thoracotomy with one-lung ventilation. The objective is to compare the analgesic efficacy of continuous thoracic paravertebral block (BPV) versus continuous thoracic epidural block (BPD) for postoperative pain control during the first 48 hours after surgery. Patients will be randomly allocated to two groups (40 per group). In the BPV group, the paravertebral catheter is inserted at the end of surgery under direct thoracoscopic vision (without ultrasound), using a bolus of ropivacaine 0.375% (15 mL fractionated) followed by continuous infusion of bupivacaine 0.125% at 0.10 mL/kg/h. In the BPD group, the epidural catheter is inserted at the beginning of surgery using the loss-of-resistance technique with the same bolus and infusion regimen. The target dermatomal level is T5-T7 (or T5-T9). The primary outcome is the mean pain score at rest measured by the Numeric Verbal Scale (NVS 0-10) at 6, 12, 24, and 48 hours postoperatively. Secondary outcomes include pain on movement, total opioid consumption (converted to morphine equivalents), block-related complications (hypotension, urinary retention, technical failure, motor block), clinically significant pulmonary and cardiovascular complications, length of hospital stay, and patient satisfaction with analgesia. Randomization is centralized using variable block sizes and sealed numbered envelopes. Outcome assessors are blinded to allocation. Both groups receive identical multimodal analgesia and a standardized rescue protocol. The sample size of 80 participants was calculated to demonstrate non-inferiority with a margin of 1 point on the NVS (expected SD = 1.5; 80% power; one-sided α = 0.025). The study was approved by the Research Ethics Committee of HCPA (Opinion No. 8.544.882; CAAE 98467026.8.0000.5327) and will be conducted in accordance with the Declaration of Helsinki and current Brazilian regulations.
Interventions
Participants randomized to the continuous thoracic paravertebral block (BPV) group. At the end of surgery and before chest tube placement, a paravertebral catheter is inserted under direct thoracoscopic vision (without ultrasound) using a Tuohy needle. A bolus of ropivacaine 0.375% (15 mL, fractionated) is administered, followed by continuous infusion of bupivacaine 0.125% at 0.10 mL/kg/h. The target level is T5-T7 (or T5-T9). The catheter remains in place for at least 48 hours postoperatively.
PROCEDUREContinuous Thoracic Epidural Block
Participants randomized to the continuous thoracic epidural block (BPD) group. At the beginning of surgery, an epidural catheter is inserted at the thoracic level using the loss-of-resistance technique. A bolus of ropivacaine 0.375% (15 mL, fractionated) is administered, followed by continuous infusion of bupivacaine 0.125% at 0.10 mL/kg/h. The target level is T5-T7 (or T5-T9). The catheter remains in place for at least 48 hours postoperatively.
Sponsors
Hospital de Clinicas de Porto Alegre
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
The study is single-blind (outcomes assessor blinded). Due to the nature of the interventions, patients and the clinicians performing or managing the blocks (thoracic surgeons and anesthesiologists) are not blinded. Outcome assessors who evaluate pain scores, opioid consumption, and complications remain blinded to participant allocation. Randomization is centralized with sealed numbered envelopes to ensure allocation concealment.
Intervention model description
This is a two-arm, parallel-group, randomized controlled non-inferiority trial. Participants are randomly assigned in a 1:1 ratio to either the continuous thoracic paravertebral block group (BPV) or the continuous thoracic epidural block group (BPD). Both groups receive catheter-based regional analgesia using the same initial bolus (ropivacaine 0.375%, 15 mL) and continuous infusion (bupivacaine 0.125% at 0.10 mL/kg/h). The parallel design allows direct head-to-head comparison of the two techniques for non-inferiority in postoperative pain control during the first 48 hours, with blinded outcome assessment.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients aged 18 years or older; * Elective thoracic surgeries requiring open thoracotomy; * American Society of Anesthesiologists (ASA) physical status I to III.
Exclusion criteria
* Pregnancy or lactation; * Urgent or emergency surgeries; * Contraindications to epidural catheter insertion or neuraxial anesthesia; * Infection at the proposed block site; * Patient refusal to undergo the study blocks; * Video-assisted thoracic surgeries; * Anticipated need for invasive mechanical ventilation in the postoperative period; * Chronic opioid use (daily use for more than 3 months of ≥10 mg oral morphine equivalent); * Severe vertebral deformities or previous thoracic spine surgery that prevent safe performance of the blocks; * Known allergy to local anesthetics, opioids, or study medications; * Body mass index \> 35 kg/m²; * Advanced liver or kidney failure (Child-Pugh C or estimated glomerular filtration rate \< 50 mL/min/1.73 m²); * Severe cognitive impairment that prevents understanding of instructions or pain assessment.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean pain intensity at rest during the first 48 hours after surgery | 6, 12, 24, and 48 hours after surgery | Mean of the pain scores at rest measured by the Numeric Verbal Scale (NVS 0-10) at 6, 12, 24, and 48 hours postoperatively. This composite measure is the primary endpoint for the non-inferiority comparison between continuous thoracic paravertebral block and continuous thoracic epidural block. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain on movement | 6, 12, 24, and 48 hours after surgery | Pain intensity during movement (e.g., coughing, sitting, or walking) assessed by Numeric Verbal Scale (0-10) at 6, 12, 24, and 48 hours postoperatively. |
| Total opioid consumption in the first 48 hours | 0 to 48 hours after surgery | Total opioid consumption (converted to intravenous morphine equivalents in mg) from the end of surgery until 48 hours postoperatively. |
| Block-related complications | During the first 48 hours after surgery | Incidence of complications related to the regional blocks, including hypotension (systolic BP \< 100 mmHg or \>20% drop from baseline), urinary retention requiring catheterization, motor block (modified Bromage scale), and technical failure of the block. |
| Clinically significant pulmonary and cardiovascular complications | Up to 72 hours after surgery | Incidence of clinically significant pulmonary complications (e.g., atelectasis requiring intervention, pneumonia) and cardiovascular complications (e.g., arrhythmias requiring treatment, ischemic events) in the first 72 hours after surgery. |
| Length of hospital stay | From surgery until hospital discharge (assessed up to 30 days) | Total number of days from surgery until hospital discharge. |
| Patient satisfaction with analgesia | 48 hours after surgery | Patient satisfaction with postoperative pain control assessed by a 5-point Likert scale (1 = very dissatisfied to 5 = very satisfied) at 48 hours after surgery. |
Countries
Brazil
Contacts
CONTACTCristiano F Andrade, MD, PhD
CONTACTAndre P. Schmidt, MD, MSc, PhD
PRINCIPAL_INVESTIGATORCristiano F Andrade, MD, PhD
Federal University of Rio Grande do Sul
Outcome results
None listed