Sensory Distribution and Postoperative Analgesia of Ultrasound-Guided Interfascial Plane Blocks in Living Liver Donors

Assessment of Sensory Block Distribution and Postoperative Analgesia Following Ultrasound-Guided Interfascial Plane Blocks in Living Liver Donors: A Prospective Observational Study

Living liver donor hepatectomy at our institution routinely includes ultrasound-guided interfascial plane blocks as part of postoperative analgesia. Although these blocks have become increasingly used in donor hepatectomy, their cutaneous sensory distributions and block-related dermatomal coverage have not been systematically evaluated, with only anecdotal reports available in the literature.

This prospective observational study aims to assess both the sensory blockade patterns and the early postoperative analgesic performance of interfascial plane blocks administered to living liver donors. Following surgery, all consenting donors receive the institution's standard block protocol. Cutaneous sensory mapping is performed in the post-anesthesia care unit (PACU) at the second postoperative hour. Pain intensity and analgesic requirements within the first 24 hours are also recorded.

The study is designed to provide objective data on the dermatomal coverage and postoperative analgesic effects of contemporary ultrasound-guided interfascial plane blocks used in living liver donor surgery.

Study Overview

• Status: Completed
• Conditions: Pain
• Intervention / Treatment: Other: interfascial plane block; Other: patient controlled analgesia device; Other: cutaneus sensory mapping

• Study Type: Observational
• Enrollment (Actual): 30

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye)
    • Bahcesehir Unişversity Medicalpark Goztepe hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult living liver donors undergoing elective donor hepatectomy at a tertiary care center. All participants receive ultrasound-guided interfascial plane blocks as part of the institution's routine postoperative analgesia protocol. Eligible donors are aged 18 to 65 years, classified as ASA physical status I-II, and able to cooperate with postoperative cutaneous sensory mapping procedures. Individuals with contraindications to regional anesthesia, conditions preventing accurate sensory assessment, or those who decline participation are excluded.

Description

Inclusion Criteria:

• Adult living liver donors undergoing elective donor hepatectomy
• Age 18 to 65 years
• ASA physical status I-II
• Patients who have received ultrasound-guided interfascial plane blocks as part of their postoperative analgesia
• Ability to cooperate with postoperative sensory mapping procedures
• Patients who agree to participate and provide written informed consent

Exclusion Criteria:

• Patients who refuse to participate or do not provide written informed consent
• Patients who have not received any ultrasound-guided interfascial plane block
• ASA physical status > II
• Presence of surgical incisions or wound complications preventing reliable sensory mapping
• Prior major abdominal surgery that may alter cutaneous innervation patterns
• Cognitive impairment limiting the ability to cooperate with sensory testing
• Known psychiatric disorders (e.g., major depression, mania, schizophrenia) that may interfere with postoperative assessment
• Local infection, skin disease, or dermatologic condition preventing accurate cutaneous mapping
• Allergy or contraindication to local anesthetics used in the block

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cutaneous sensory block area mapping for different regional anesthesia techniques in liver donor surgery	The cutaneous sensory block area produced by the regional anesthesia technique will be evaluated at the 120th minute post-block using a standardized pinprick test. Sensory borders will be identified radially and marked on the skin with a UV-visible marker. Each mapped region will be photographed with a calibrated reference scale placed on the skin. These images will be processed using a predefined digital template to calculate the total blocked surface area in square centimeters. The resulting measurements will be used to characterize the sensory distribution of the interfascial plane blocks in living liver donors.	At 120 minutes after block administration in the post-anesthesia care unit (PACU).

Collaborators and Investigators

• Sponsor: Bahçeşehir University

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2025
• Primary Completion (Actual): May 21, 2026
• Study Completion (Actual): May 21, 2026

Study Registration Dates

• First Submitted: November 19, 2025
• First Submitted That Met QC Criteria: November 19, 2025
• First Posted (Actual): November 26, 2025

Study Record Updates

• Last Update Posted (Actual): May 26, 2026
• Last Update Submitted That Met QC Criteria: May 21, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain
• Other Study ID Numbers: Liver mapping

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No