Epidural Catheter Placement Techniques by Anesthesia Residents: Success and Complications

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.

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.

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