Evaluation of the Surgical Pleth Index During Spinal and General Anesthesia

Study Overview
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Brief Summary
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The Surgical Pleth index (SPI) has been introduced as a non invasive tool to measure stress and pain during surgery. Preliminary studies were performed in patients under general anaesthesia with propofol and remifentanil. These trials showed a good correlation between SPI and aching procedures and a negative correlation between SPI and the remifentanil dosage. Hence, it was concluded that SPI may be a bedside tool to measure 'pain' during surgery. So far, no study investigated SPI during regional anaesthesia.

Detailed Description
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Spinal anaesthesia secures full pain relieve and muscle relaxation usually in the lower part of the body. Thus, SPI - a measure that reflects pain during surgery - may not exceed significantly compared to baseline. It may slightly increase only during administration of the block. Increasing SPI values due to surgery under subarachnoid block may reflect intraoperative patient's stress mediated by activation of the autonomic nervous system, specifically sympathetic activation. In consistence with previously published data no changes of SPI should occur due to standardized sedation with propofol.

Official Title
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The Effects of Sedation and Analgesia on the Surgical Pleth Index (SPI)

Conditions
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Stress, Pain

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: surgical procedures feasible under general or spinal anesthesia duration between 30 and 90 min ASA status I,II or III Exclusion Criteria: contraindications against one of the anesthesia methods age under 18 emergencies chronical pain history lack of sinus rhythm

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| General Anesthesia<br>Patients undergoing short-term surgery (30-90 min) under general anesthesia | |
| Spinal<br>Patients undergoing short-term surgery (30-90 min) under spinal anesthesia | |
| Spinal + Sedation<br>Patients undergoing short-term surgery (30-90 min) under spinal anesthesia with sedation | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference Between All Groups for the Surgical Pleth Index(SPI) at Defined Timepoints | Surgical Pleth Index (SPI), derived from finger photoplethysmographic signal has a range from 0 showing the lowest stress level to 100 showing the maximum stress level. SPI was compared between the groups during six defined time points: baseline (BL)- day before surgery; induction (IND)-before induction of general anesthesia or before spinal punction respectively; intubation (INT) or spinal punction (SPA); skin incision (INC), surgical suture (SU) and 10 minutes after admission to the recovery room (PACU). Difference between the groups is calculated using ANOVA. | Time points for outcome measures: Baseline, before Induction of anesthesia, during Intubation or Spinal Punction, during Skin Incision, during Surgical Suture, during Post Anesthesia Care Unit stay | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Analgesia, Sedation, Spinal, Stress, Surgical, Surgical Stress, Pain