Paravertebral block by proxy and local anesthetic concentrations

JRCT ID: jRCT1031240233

Registered date:24/07/2024

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: Spontaneous pneumothorax, patients undergoing lobectomy for lung tumours
• Date of first enrollment: 24/07/2024
• Target sample size: 30
• Study type: Interventional
• Intervention(s): Two types of paravertebral proximal blocks are performed and blood local anaesthetic concentrations are measured at defined times after local anaesthetic injection. The maximum plasma concentration of local anaesthetic C max and the time to reach the maximum plasma concentration for paraspinal block and block in the shallow layer of the superior transverse costovertebral ligament (costotransverse block, mid-point transverse process to pleura block) Tmax (min) are measured and compared.

Outcome(s)

• Primary Outcome: Determine the maximum local anaesthetic plasma concentration C max and the time Tmax (min) to reach the maximum plasma concentration from the value of the ropivacaine plasma concentration at 5min, 10min, 15min, 30min, 45min, 60min, 90min and 120 min after nerve block.
• Secondary Outcome: Patient pain score VAS or NRS after extubation in the operating theatre (0 h, 2 h, 6 h, before sleep, next morning after surgery, 24 h after extubation), record of analgesic use, presence of PONV, vital signs on leaving the operating theatre (max/min/average blood pressure, respiratory rate, pulse rate), other, patient information and treatment from the electronic anaesthetic record Information and treatment details, number of cases requiring additional prescriptions for rescue analgesia (NSAIDs, weak opioid analgesics) in the intensive care unit and the time since awake extubation when that additional analgesia was requested.

Key inclusion & exclusion criteria

• Age minimum: >= 20age old
• Age maximum: Not applicable

Include criteria

1) Adults 20 years of age or older
2) Those who fall under BMI 18.5 to 25.0 kg/m2
3) Patients with American Society of Anesthesiologists Pre-Anesthesia Risk Assessment (ASA-PS) 3 or less (ASA-PS Classification 1: No organic, biochemical or psychiatric abnormalities. Classification 2: Mild to moderate systematic impairment. Classification 3: Severe systematic disorder. Classification 4: Severe, life-threatening systemic disorders that cannot be cured by surgery (Classification 5: Dying). Classification 5: Dying.)
4) Persons who give written consent to participate in the research.

Exclude criteria

1) Patients who do not meet the above selection criteria
2) Patients allergic to amide-type local anesthetics
3) Patients on anticoagulation therapy with PT-INR (Prothrombin Time International Normalized Ratio) > 1.2 or on dual anti-platelet therapy (DAPT), excluding biaaspirin monotherapy and prophylactic low molecular weight heparin therapy
4) Patients with any of the contraindications listed in the package insert.
5) Patients with moderate to severe hepatic dysfunction
6) Patients with arrhythmia requiring pacemaker insertion
7) Patients who meet all of the above selection criteria and none of the above exclusion criteria.
8) Patients who have refused to participate in this study.

Related Information

• Primary Sponsor: Nakazawa Keisuke