Skin Conductance for Predicting Spinal Anesthesia-Induced Hypotension in Geriatric Urologic Oncology Patients

Official title

Skin Conductance as a Predictor of Spinal Anesthesia-Induced Hypotension in Geriatric Oncology Patients

Overview

Spinal anesthesia-induced hypotension is a common and clinically significant complication in elderly patients undergoing oncologic surgery. Early identification of patients at risk for hemodynamic instability remains a major challenge in perioperative management. Skin conductance reflects sympathetic nervous system activity and may provide a noninvasive indicator of autonomic responses. This prospective observational study aims to evaluate whether skin conductance measurements can predict the development of hypotension following spinal anesthesia in geriatric oncology patients undergoing urologic surgery. The findings may contribute to improved perioperative monitoring and early risk stratification in this vulnerable patient population.

Detailed description

Spinal anesthesia is widely used in urologic oncology surgery due to its favorable analgesic profile and reduced systemic anesthetic exposure. However, spinal anesthesia frequently leads to significant hemodynamic changes, particularly hypotension, which is more pronounced in elderly patients because of age-related alterations in autonomic regulation, reduced cardiovascular reserve, and increased comorbidity burden. Spinal anesthesia-induced hypotension may result in inadequate tissue perfusion and increased perioperative morbidity, making early identification of patients at risk an important aspect of perioperative management.

Skin conductance is a noninvasive physiological parameter reflecting sympathetic nervous system activity and sudomotor responses. Changes in skin conductance have been associated with variations in autonomic nervous system activity and may provide an indirect indicator of hemodynamic responses. Continuous monitoring of skin conductance may therefore offer a potential method for identifying patients who are more likely to develop hypotension after spinal anesthesia.

The aim of this prospective observational study is to investigate the relationship between skin conductance measurements and the development of hypotension following spinal anesthesia in geriatric oncology patients undergoing urologic surgery. Hemodynamic parameters including blood pressure and heart rate will be monitored perioperatively, and their association with skin conductance measurements will be evaluated. The results of this study may contribute to improving perioperative monitoring strategies and risk prediction in elderly oncology patients undergoing spinal anesthesia.

Interventions

• Other Skin Conductance Monitoring
  Skin conductance will be continuously monitored using a noninvasive electrodermal activity monitoring device to assess sympathetic nervous system activity during the perioperative period. Measurements will be recorded before and after spinal anesthesia and evaluated in relation to the development of spinal anesthesia-induced hypotension.

Primary outcome measures

• Number of Participants with Spinal Anesthesia-Induced Hypotension [Time frame: From initiation of spinal anesthesia until 20 minutes after spinal anesthesia.]

Secondary outcome measures (4)

• Incidence of Bradycardia After Spinal Anesthesia [Time frame: From initiation of spinal anesthesia until 20 minutes after spinal anesthesia]
• Maximum Percentage Decrease in Mean Arterial Pressure (MAP) [Time frame: From initiation of spinal anesthesia until 20 minutes after spinal anesthesia.]
• Number of Participants Requiring Vasopressor Administration [Time frame: From initiation of spinal anesthesia until 20 minutes after spinal anesthesia.]
• Changes in Skin Conductance Values [Time frame: From baseline measurement before spinal anesthesia until 20 minutes after spinal anesthesia]

Eligibility criteria

Inclusion criteria

• Patients aged 65 years and older
• Patients scheduled for elective urologic oncology surgery under spinal anesthesia
• American Society of Anesthesiologists (ASA) physical status I-III
• Patients who provide written informed consent to participate in the study

Exclusion criteria

• Refusal to participate or inability to provide informed consent
• Contraindication to spinal anesthesia (e.g., infection at puncture site, coagulopathy)
• Severe cardiac conduction abnormalities or presence of a cardiac pacemaker
• Severe autonomic dysfunction or known neuropathy affecting autonomic responses
• Use of medications that significantly affect autonomic nervous system activity
• Baseline hypotension or hemodynamic instability before spinal anesthesia
• Inability to obtain reliable skin conductance measurements (e.g., severe skin lesions at electrode placement site)

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model

Cohort

Study locations

Turkey (Türkiye) · 1 center

• Dr. Abdurrahman Yurtaslan Ankara Oncology Education and Research Hospital Clinic of Anesth — Ankara

Publications

• Norbeck DW, Lindgren S, Wolf A, Jildenstal P. Reliability of nociceptive monitors vs. standard practice during general anesthesia: a prospective observational study. BMC Anesthesiol. 2025 Jan 31;25(1):51. doi: 10.1186/s12871-025-02923-4. PMID 39891061
• Storm H. Changes in skin conductance as a tool to monitor nociceptive stimulation and pain. Curr Opin Anaesthesiol. 2008 Dec;21(6):796-804. doi: 10.1097/ACO.0b013e3283183fe4. PMID 18997532
• Ledowski T, Preuss J, Kapila R, Ford A. Skin conductance as a means to predict hypotension following spinal anaesthesia. Acta Anaesthesiol Scand. 2008 Nov;52(10):1342-7. doi: 10.1111/j.1399-6576.2008.01697.x. PMID 19025525

Identifiers

NCT: NCT07481851 · 2025-12/205

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗