Effect of Pre- and Postoperative ESP Block on Frontal QRS-T Angle in Laparoscopic Cholecystectomy

Harran University

Status: Enrolling

Conditions: Electrocardiography; Pain, Postoperative; Cholecystectomy, Laparoscopic; Cardiac Electrophysiology; Regional Anesthesia

Treatments: Procedure: Preoperative Erector Spinae Plane Block; Drug: Bupivacaine; Procedure: Standard General Anesthesia; Procedure: Postoperative Erector Spinae Plane Block

Study type: Interventional

Funder types: Other

Identifiers

NCT07058194

Veli Frontal

Details and patient eligibility

About

This study aims to investigate the effects of preoperative and postoperative Erector Spinae Plane (ESP) block on the frontal QRS-T angle, a marker of cardiac electrophysiological instability, in patients undergoing laparoscopic cholecystectomy. A total of 120 patients aged 18-65 with ASA I-II status will be randomized into three groups: Control (no ESP), Preoperative ESP, and Postoperative ESP. Electrocardiograms (ECGs) will be obtained preoperatively and one hour postoperatively to assess changes in QRS-T angle and other repolarization parameters. This randomized controlled trial will help clarify the potential cardiac effects of ESP block depending on its timing and may provide insight into optimizing anesthetic safety in surgical patients.

Full description

Erector Spinae Plane (ESP) block is widely used in laparoscopic surgeries for postoperative pain control due to its simplicity and efficacy. However, its influence on the autonomic nervous system and subsequent cardiovascular effects, including changes in cardiac electrophysiological parameters, remains insufficiently understood. The frontal QRS-T angle has emerged as a novel and reliable ECG-derived marker associated with increased cardiac risk and ventricular repolarization heterogeneity.

This prospective, randomized, controlled, single-center trial aims to evaluate the impact of ESP block timing on the frontal QRS-T angle. A total of 120 adult patients scheduled for elective laparoscopic cholecystectomy will be randomly assigned into three groups:

Control group (no ESP block),

Preoperative ESP block group,

Postoperative ESP block group.

Bilateral ESP blocks will be administered using 0.25% bupivacaine under ultrasound guidance at the T7 level. Standard general anesthesia will be applied to all patients. ECG recordings will be obtained preoperatively and at the first postoperative hour to calculate the frontal QRS-T angle, QT interval, QTc, Tp-e, Tp-e/QT, and Tp-e/QTc ratios.

The primary outcome is the change in the frontal QRS-T angle. Secondary outcomes include pain scores (VAS), analgesic consumption, and other ECG-based repolarization markers. The findings may enhance perioperative cardiac risk stratification and inform decisions on the optimal timing of ESP block administration in surgical patients with potential cardiac vulnerability.

Enrollment: 120 estimated patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age between 18-65 years
• ASA physical status I-II
• Scheduled for elective laparoscopic cholecystectomy
• Voluntary written informed consent obtained
• Normal preoperative 12-lead ECG (no conduction abnormalities or arrhythmias)

Exclusion criteria

• History of cardiac disease (e.g., arrhythmia, myocardial infarction, heart failure)
• Current use of medications affecting cardiac conduction (e.g., antiarrhythmics, beta-blockers)
• Known allergy to local anesthetics
• Coagulation disorders or current anticoagulant therapy
• Pregnancy or breastfeeding
• Local infection or anatomical deformity at the ESP block injection site
• Patients with psychiatric or neurological disorders impairing cooperation

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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120 participants in 3 patient groups

Preoperative ESP Block Group

Experimental group

Description:

Patients in this group will receive bilateral ultrasound-guided erector spinae plane (ESP) block at the T7 level with 20 mL of 0.25% bupivacaine on each side (total 40 mL) before the induction of general anesthesia. ECG will be recorded preoperatively and at 1 hour postoperatively. Frontal QRS-T angle, QT interval, QTc, Tp-e interval, and Tp-e/QTc ratio will be analyzed.

Treatment:

Procedure: Standard General Anesthesia

Drug: Bupivacaine

Procedure: Preoperative Erector Spinae Plane Block

Postoperative ESP Block Grou

Experimental group

Description:

Patients in this group will undergo standard general anesthesia. At the end of surgery, bilateral ESP block will be applied at the T7 level using 20 mL of 0.25% bupivacaine per side. ECG will be taken preoperatively and at 1 hour after surgery to evaluate changes in cardiac electrophysiologic parameters including the Frontal QRS-T angle.

Treatment:

Procedure: Postoperative Erector Spinae Plane Block

Procedure: Standard General Anesthesia

Drug: Bupivacaine

Control Group (No ESP Block)

Active Comparator group

Description:

Patients in the control group will receive standard general anesthesia only, without any regional block. Preoperative and 1-hour postoperative ECGs will be obtained for comparison of electrophysiologic markers such as Frontal QRS-T angle, QT, QTc, Tp-e, and Tp-e/QTc.

Treatment:

Procedure: Standard General Anesthesia