Surgical Pleth Index: Predicting the Optimal Timing for Tracheal Intubation During General Anesthesia

Study Overview
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Brief Summary
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Surgical pleth index (SPI) has been widely investigated in assessing the nociceptive level, and tracheal intubation is a noxious stimulus during the induction of anesthesia. This study aims to evaluate the ability of SPI to predict hemodynamic reactivity after tracheal intubation, and find the target value of SPI to guide the optimal timing for tracheal intubation.

Detailed Description
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The surgical pleth index (SPI)monitored by a oxygen saturation (Spo2) probe, is a dimensionless score which is based on the photoplethysmographic analysis of the pulse wave and the heartbeat interval. SPI score monitored during surgery is the indicator that may reflect a patient's autonomic response to certain noxious stimulus and is correlated to his/her nociception level. Once noxious stimulus occur, sympathetically-mediated vasoconstriction and cardiac autonomic tone increasing can be reflected by SPI. Several studies have since investigated the potential benefits of SPI-guided anesthesia, such as SPI could reduce the intraoperative opioid consumption and facilitate extubation after surgery.Jain N et al. found that the need for postoperative analgesics decreased although fentanyl consumption increased, when SPI guided opioid use Intraoperatively . The level of SPI was also reported to be able to predict postoperative pain, which could guide clinical use of opioids and improve patient postoperative satisfaction. Recent studies on SPI mainly focus on the maintenance period of anesthesia and postoperative analgesia, and there is few studies on the application of SPI in anesthesia induction period. Hemodynamic stability in induction period has always been the technical key point that anesthesiologists pay attention to, especially for patients with cardiovascular and cerebrovascular diseases, maintaining hemodynamic stability is particularly important. Endotracheal intubation is a common procedure during general anesthesia. The hemodynamic fluctuation caused by intubation stimulation is usually caused by the premature timing of intubation. At present, the timing of intubation is much depended on the clinical experience of an anesthesiologist, such as according to the degree of blood pressure, heart rate decline or predicted onset of propofol,opioid and neuromascular blocker. This study aims to explore whether the SPI can be used in quantitative prediction of intubation timing or prediction the hemodynamic reactivity after intubation, and to investigate the influence of age and gender on SPI value.

Official Title
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Dose Surgical Pleth Index Play a Role to Predict Optimal Timing for Tracheal Intubation During Anesthetic Induction?

Conditions
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Trachea Intubation

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiology physical status (ASA) 1-2 Patients aged 18-80 years undergoing non-emergency anesthesia Exclusion Criteria: age <18 years severe peripheral or cardiac neuropathy significant arrhythmia (i.e. atrial fibrillation or atrioventricular block) pacemaker neurovascular diseases uncontrolled hypertension treatment with vasoactive medication during the induction of anesthesia any intraoperative treatment with beta receptor blockers, clonidine, beta receptor agonists, or any other drug suspected to interact with the sympathovagal balance predicted difficult ventilation chronic pain requiring long-term analgesics addictive to opioids.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ability of SPI to predict hemodynamic reactivity after tracheal intubation in general population | The area under receiver-operating characteristic curve (AUC) of SPI | within 2 minutes after trachea intubation | 
| ability of SPI to predict hemodynamic reactivity after tracheal intubation in female | The area under receiver-operating characteristic curve (AUC) of SPI | within 2 minutes after trachea intubation | 
| ability of SPI to predict hemodynamic reactivity after tracheal intubation in male | The area under receiver-operating characteristic curve (AUC) of SPI | within 2 minutes after trachea intubation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| influence factors of hemodynamic reactivity | using logistic regression model | within 2 minutes after trachea intubation | 
| Cardiovascular stress level | delta rate pressure product (ΔRPP) between different ranges of SPI | within 2 minutes after trachea intubation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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surgical pleth index, hemodynamic reactivity, trachea intubation