Epidural Catheter Placement Techniques by Anesthesia Residents: Success and Complications (EPİ-TECH)

Anesthesia Residents' Epidural Catheter Placement Techniques: A Prospective Observational Study on Success Rates and Complications

This prospective observational study aims to evaluate the impact of epidural catheter placement techniques - loss of resistance (LOR) and hanging drop (HD) - on first-attempt success rates and procedural complications among anesthesia residents. Residents with at least two years of training will perform epidural catheterization under supervision for patients scheduled for elective surgery requiring perioperative epidural analgesia. An independent observer will record procedural details, complications, and postoperative pain scores. The study will enroll 440 patients aged 18-80 with ASA I-III classification.

Study Overview

• Status: Not yet recruiting
• Conditions: Postoperative Pain; Education; Epidural Anesthesia; Graduate Medical Education; Catheterisation; Medical
• Intervention / Treatment: Procedure: epidural catheter placement

Detailed Description

Epidural catheterization is a cornerstone technique in perioperative and obstetric pain management. Two established methods are commonly used to identify the epidural space: the loss of resistance (LOR) technique, using air or normal saline, and the hanging drop (HD) technique. Although both are widely employed, comparative data on their performance by residents in training are limited. This study prospectively observes which technique the resident chooses, records procedural parameters (depth of epidural space, number of attempts, level of insertion), and documents immediate complications (dural puncture, intravascular placement, paresthesia, hypotension) and postoperative outcomes (NRS scores at 0, 6, 12, and 24 hours; PDPH). Cases in which a resident is unable to complete the procedure are documented separately, including the reason for failure and subsequent management by a supervising specialist. All procedures are performed using an 18G Tuohy needle and standard catheter set. A test dose is administered to all patients following catheter placement. Data are recorded by an independent observer using a standardized data collection form.

• Study Type: Observational
• Enrollment (Estimated): 440

Contacts and Locations

• Study Contact: Name: dilara göçmen, Asst prof; Phone Number: +90 216 625 4545; Email: dilara.gocmen@marmara.edu.tr

Study Locations

• Turkey (Türkiye)
  • Maltepe
    • Istanbul, Maltepe, Turkey (Türkiye), 34852
      • Marmara University Pendik Training and Research Hospital
      • Contact: dilara göçmen, Asst prof; Phone Number: +90 216 625 4545; Email: dilara.gocmen@marmara.edu.tr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Adult patients scheduled for elective/emergency surgery with planned perioperative epidural analgesia or anesthesia at Marmara University Pendik Training and Research Hospital, Department of Anesthesiology and Reanimation.

Description

Inclusion Criteria:

• Age 18-80 years
• ASA physical status I, II, or III
• Scheduled for elective surgery requiring perioperative epidural analgesia or anesthesia (lumbar or thoracic approach)
• Epidural catheter to be placed by a resident with ≥ 2 years of anesthesia training

Exclusion Criteria:

• Spinal deformity (scoliosis, kyphosis, or prior spinal surgery at the target level)
• Coagulopathy or anticoagulant therapy precluding neuraxial blockade
• Active infection at the insertion site or systemic infection
• Pre-existing neurological disease affecting the spinal cord or nerve roots
• Emergency surgery
• History of prior failed epidural catheterization
• Patient refusal or inability to provide written informed consent
• Local anatomical pathology precluding safe epidural access

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Loss of Resistance (LOR) Group; Patients in whom the epidural space is identified using the loss of resistance technique. The attending resident uses a syringe filled with air or normal saline attached to the Tuohy needle hub and advances until resistance disappears upon entering the epidural space.	Procedure: epidural catheter placement; Epidural catheterization performed using an 18G Tuohy needle and standard catheter set by anesthesia residents with a minimum of two years of training, under specialist supervision. Technique selection (LOR or HD) is at the discretion of the performing resident and is not randomized.; Other Names: neuroaxial blockade
Hanging Drop (HD) Group; Patients in whom the epidural space is identified using the hanging drop technique. A drop of normal saline is placed at the Tuohy needle hub and observed to be aspirated inward by the negative epidural pressure as the needle tip traverses the ligamentum flavum.	Procedure: epidural catheter placement; Epidural catheterization performed using an 18G Tuohy needle and standard catheter set by anesthesia residents with a minimum of two years of training, under specialist supervision. Technique selection (LOR or HD) is at the discretion of the performing resident and is not randomized.; Other Names: neuroaxial blockade

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
First-attempt success rate	Defined as successful epidural space identification and catheter placement in a single Tuohy needle insertion attempt, without redirecting the needle.	Time Frame: Immediately upon procedure completion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dural puncture rate	Inadvertent dural puncture defined as free flow of cerebrospinal fluid through the Tuohy needle or epidural catheter, confirmed by visual inspection. Recorded as yes/no by the independent observer at the time of the procedure	Intraoperative
Catheter Advancement Failure Rate	Inability to thread the epidural catheter beyond 3 cm into the epidural space despite confirmed needle placement, necessitating needle repositioning or procedure abandonment. Recorded as yes/no by the independent observer.	intraoperative
Operator-Assessed Difficulty Score	The performing resident rates the overall technical difficulty of the procedure immediately upon completion using a 5-point Likert scale: 1 = very easy, 2 = easy, 3 = moderate, 4 = difficult, 5 = very difficult. Recorded on the standardized data collection form	Immediately after procedure completion
Intravascular catheter placement rate	Unintentional intravascular placement defined as aspiration of blood through the epidural catheter prior to test dose administration. Recorded as yes/no by the independent observer immediately following catheter advancement	intraoperative
Postoperative Pain Scores	Pain intensity assessed using the Numerical Rating Scale (NRS), where 0 = no pain and 10 = worst imaginable pain. Recorded at four time points: immediately upon arrival to the recovery unit (0 hours), and at 6, 12, and 24 hours postoperatively by the independent observer.	0, 6, 12, and 24 hours postoperatively
Rate and Type of Assistance Required During Catheter Placement	The level of assistance received by the performing resident is recorded in three categories: (1) No assistance - procedure completed independently; (2) Verbal guidance only - supervising specialist provides verbal instructions without physical intervention; (3) Physical assistance - supervising specialist takes over needle or catheter manipulation partially or completely. Recorded by the independent observer at the time of the procedure.	Intraoperative
First-Attempt Success Rate Stratified by Resident Seniority Level	First-attempt success rates are compared across three seniority strata defined by duration of anesthesia training: junior residents (2-3 years), intermediate residents (3-4 years), and senior residents (4 years and above). Seniority is determined by the total duration of anesthesia specialty training at the time of the procedure.	Intraoperative

Collaborators and Investigators

• Sponsor: Marmara University Pendik Training and Research Hospital

Publications and helpful links

General Publications

• 1. Hoffmann VL, Vercauteren MP, Vreugde JP, Hans GH, Coppejans HC, Adriaensen HA. Posterior epidural space depth: safety of the loss of resistance and hanging drop techniques. British Journal of Anaesthesia. 1999;83(5):807-811. 2. Günaydın B, Tan A, Doğru O, Mutlu M, Öztürk G, Güler HG. Comparison of spring-loaded, loss of resistance and hanging drop techniques in lumbar epidural blocks. Agri. 2012;24(1):13-18. 3. Azizov S, Okcu M, Goksu H. Could the Hanging Drop Technique Be an Alternative Method to Loss of Resistance in Cervical Epidural Injections? Pain Physician. 2025;28:217-221. 4. Tran DQH, González AP, Bernucci F, Finlayson RJ. Confirmation of Loss-of-Resistance for Epidural Analgesia. Regional Anesthesia and Pain Medicine. 2015;40(2):166-173. 5. Yoshida K, Tanaka S, Watanabe K. Hanging-Drop Technique Is More Suitable for Epidural Space Confirmation in Patients With Subcutaneous Emphysema After Traumatic Multiple Rib Fractures. Journal of Cardiothoracic and Vascular Anesthesia. 2023;37(12). 6. Konrad C, Schüpfer G, Wietlisbach M, Gerber H. Learning manual skills in anesthesiology: Is there a recommended number of cases for anesthetic procedures? Anesthesia & Analgesia. 1998;86(3):635-639. 7. De Oliveira GS, Glassenberg R, Chang R, Fitzgerald P, McCarthy R. Virtual airway simulation to improve dexterity among novices performing fibreoptic intubation. Anaesthesia. 2013;68(10):1053-1058. 8. Kopacz DJ, Neal JM, Pollock JE. The regional anesthesia learning curve. Regional Anesthesia. 1996;21(3):182-190. 9. Naik VN, Devito I, Halpern SH. Cusum analysis is a useful tool to assess resident proficiency at epidural anesthesia. Canadian Journal of Anesthesia. 2004;51(7):703-708.

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: May 1, 2026
• First Submitted That Met QC Criteria: May 1, 2026
• First Posted (Actual): May 7, 2026

Study Record Updates

• Last Update Posted (Actual): May 7, 2026
• Last Update Submitted That Met QC Criteria: May 1, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: epidural catheter; epidural space identification; loss of resistance; hanging drop; procedural training
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain, Postoperative
• Other Study ID Numbers: mü anesthesia

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