Caudal epidural anesthesia was reported as the first epidural anesthesia technique in 1933, but its use began to become widespread after the 1960s (1). The procedure is reliable, easy to perform, the incidence of complications is low, and the total complication rate is 1.5/1000; Serious complications occur at a rate of 1/40000. There are many methods to demonstrate the success of caudal epidural block. Some of the common traditional methods are changes in mean arterial pressure and heart rate. These methods are sometimes not objective and take time. In this study, we will examine the block success in pediatric patients who underwent caudal epidural block, which is applied in our hospital, whether the Galvanic skin response measured with a finger probe, other than traditional methods, correlates with the block success, and whether it shows faster block success compared to other traditional methods.

A successful caudal epidural block can provide safe, effective regional anesthesia. (4). The overall failure rate of caudal epidural block in pediatric patients is approximately 4%, depending on the anatomical and developmental abnormalities of the caudal canal (5,6). Therefore, reliable and rapid evaluation of a successful caudal epidural block is important to optimize anesthesia management in pediatric patients. Evaluating the success of caudal epidural block with traditional methods such as mean arterial pressure (MAP) and heart rate (HR) does not give completely objective results and takes time. Galvanic Skin Response (GSR) is a parameter that shows sweat gland function related to the autonomic nervous system. Physically, the galvanic skin response is the change in the electrical structure of the skin in response to various stimuli (7).Changes in tension measured from the skin surface are recorded. The relaxation and calming response accompanies an increase in skin resistance, while the fight response accompanies a decrease in skin resistance. In general, low conductivity is a sign of relaxation. High conductivity is a sign of emotional, mental or physical arousal (8). Galvanic Skin Response (GSR) evaluation is a non-invasive measurement that allows us to observe skin resistance changes with two probes attached to the fingertip. The aim of this study is to evaluate whether using Galvanic skin response (GSR) values measured with a finger probe will detect the success of caudal epidural block more quickly than other traditional methods in pediatric patients who underwent surgery with caudal epidural block.

Inclusion Criteria:

• lower abdominal/urogenital/lower extremity surgery
• Patients with ASA1-2

Exclusion Criteria:

• Those with neuromuscular disease
• PATIENTS WITH ASA3-4
• patients with cerebral palsy
• patients in mental reter

PEDIATRIC GROUP BETWEEN 1-6 YEARS