An observational study in Spinal Anesthesia and Total Knee Arthroplasty, sponsored by Sevim Şenol Karataş. Completed at 1 site in Turkey (Türkiye). Open to participants aged 45 Years to 85 Years. Per ClinicalTrials.gov, last updated 2025-12-03.
Sponsored by Sevim Şenol Karataş · Observational
This prospective, single-center, observational study aims to evaluate changes in the frontal QRS axis on ECG before and after spinal anesthesia in patients undergoing total knee arthroplasty. The primary objective is to determine whether spinal anesthesia causes a significant alteration in the frontal QRS axis. A total of 80 patients will be enrolled, and preoperative and postoperative ECG measurements will be compared using paired t-test or Wilcoxon signed-rank test depending on data distribution.
This study will be conducted in the Department of Anesthesiology and Reanimation at Elazığ Fethi Sekin City Hospital. It is a prospective, observational, and single-center study designed to evaluate the impact of spinal anesthesia on the frontal QRS axis in patients undergoing elective total knee arthroplasty.
The primary endpoint is the difference between preoperative and postoperative frontal QRS axis measurements. ECG recordings will be taken within 2 hours before and after surgery. Frontal QRS axis values will be automatically calculated by the ECG machine and verified manually.
Inclusion criteria include patients aged 45-85 years, ASA class I-III, undergoing spinal anesthesia for elective knee replacement surgery, and able to obtain ECG recordings before and after the procedure. Patients with arrhythmias such as atrial fibrillation or pacemaker dependency, or those requiring postoperative ICU care or general anesthesia conversion will be excluded.
The estimated sample size was calculated using G*Power software. Based on previous studies, a minimum of 34 patients is required to detect a clinically significant change of 10 degrees in QRS axis, with a planned enrollment of 80 patients considering data loss.
Statistical analysis will be conducted using SPSS 26.0. A p-value \<0.05 will be considered statistically significant.
Sevim Şenol Karataş is the lead sponsor of 5 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients aged 45-85 years undergoing elective total knee arthroplasty under spinal anesthesia at Elazığ Fethi Sekin City Hospital.
Exclusion Criteria:
Patients undergoing elective total knee arthroplasty under spinal anesthesia. Frontal QRS axis will be measured using standard 12-lead ECG preoperatively (within 2 hours before surgery) and postoperatively (within 2 hours after surgery and before mobilization). The study aims to evaluate the change in frontal QRS angle following spinal anesthesia.
Change in Frontal QRS Axis After Spinal Anesthesia
To evaluate the difference in frontal QRS axis values on the electrocardiogram (ECG) before and after spinal anesthesia in patients undergoing total knee arthroplasty.
Time frame: From 2 hours before to 2 hours after surgery
Plan to share: No
No publications or documents are linked to this record.
This study is completed, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Sevim Şenol Karataş