The optimal concentration of ropivacaine used for transversus thoracic muscle plane block

JRCT ID: jRCT1031230585

Registered date:22/01/2024

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: ASA-PS II-IV patients between 18 and 80 years of age scheduled to undergo open heart surgery
• Date of first enrollment: 28/10/2024
• Target sample size: 70
• Study type: Interventional
• Intervention(s): After induction of general anesthesia, an ultrasound-guided transversus thoracic muscle plane block is performed on the patient. Administer ropivacaine at preset concentrations of 0.4 mL/kg on one side and 0.8 mL/kg on both sides using a biased coin designed up-and-down-method. The first case uses 0.2% ropivacaine.

Outcome(s)

• Primary Outcome: The primary endpoint is the success or failure of transversus thoracic muscle plane block. Efficacy is judged as block failure if blood pressure or heart rate within 2 minutes after median sternotomy increases by more than 20% from the baseline value measured at the end of anesthesia induction, and as successful block if the increase is less than 20%.

Secondary Outcome

Additional narcotic analgesics (fentanyl/remifentanil) from post skin incision to completion of median sternotomy.
Time from the end of the block to the midline sternotomy.
Postoperative pain (NRS) score.
The total amount of fentanyl and remifentanil used intraoperatively and postoperatively.
Time to completion of ventilatory management.
Postoperative ICU length of stay.
Frequency of postoperative nausea and vomiting.
Presence of postoperative complications (wound infection, pneumonia, etc.).
Presence or absence of wound pain three months after surgery, (NRS pain score based on mailed questionnaire) .
Changes in blood test results from preoperative period.

Key inclusion & exclusion criteria

• Age minimum: >= 18age old
• Age maximum: < 80age old
• Gender: Both

Include criteria

1) Patients undergoing cardiac surgery under median sternotomy.
2) Patients with American Society of Anesthesiologist(ASA)-physical status classification II-IV.
3) Patients who are 18 years old or older and younger than 80 years old at the time of obtaining consent.
4) Patients who have been fully informed of the study and who have given written consent of their own free will.

Exclude criteria

Patients with the following conditions will be excluded from the study
1) Previous median sternotomy
2) Deformity near the sternum (e.g., funnel chest)
3) Neuropathy near the puncture site
4) Nerve block puncture site infection
5) History of allergy to local anesthetics or drugs used for general anesthesia
6) Pregnancy
7) Emergency surgery
8) Heart failure with NYHA Classification IV symptoms
9) Pulmonary hypertension requiring inhalation of nitric oxide
10) Preoperative ventilatory management
11) Serious blood coagulation disorder (platelet count less than 50000/mcL, PT% less than 60%, APTT 15 seconds longer than control value)
12) Patients with serious systemic diseases
13) Cases of infective endocarditis
14) Patients on drugs that inhibit CYP1A2
15) Other patients deemed inappropriate as subjects by the investigator

Related Information

• Primary Sponsor: Tachi Keitaro
• Source(s) of Monetary Support: University of Tsukuba Hospital