An observational study in Anesthesia Induced Hypotension and Hypotension Drug-Induced, sponsored by Kocaeli City Hospital. Completed at 1 site in Turkey. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2025-05-30.
Sponsored by Kocaeli City Hospital · Observational
This study aims to explore the frequent occurrence of hypotension during anesthesia induction due to anesthetic drugs or fasting. Predicting this condition is important for patient safety and anesthesia management. The study examines two indices: the Pleth Variability Index (PVI), derived from pulse oximeter readings, and the Diastolic Shock Index (DSI), calculated using heart rate and diastolic blood pressure. While PVI is a well-known method, DSI has been less explored in predicting anesthesia-related hypotension. The study aims to compare the effectiveness of these two indices in forecasting hypotension during anesthesia induction.
Hypotension is frequently observed during anesthesia induction due to the effects of anesthetic drugs on hemodynamics and the requirement of a specific fasting period before surgery. Induction-related hypotension can lead to decreased tissue perfusion and, consequently, secondary organ damage. Predicting anesthesia-induced hypotension in advance contributes to better anesthesia management and patient safety (1). Induction-related hypotension is defined as arterial hypotension occurring within the first 20 minutes after anesthesia induction or until the start of the surgery. Arterial hypotension is identified when mean systolic arterial pressure (MAP) decrease > 20% or MAP \<65 mmHg or when norepinephrine is administered at a dose >;6 mcg/min at least once during this period (2).
The peripheral perfusion index (PI) is a simple, cost-effective monitoring method derived from non-invasive plethysmographic data using pulse oximetry. It provides an assessment of fluid status based on respiratory changes in pulse oximeter waves, with higher PI values indicating lower arterial tone. Changes in PI are interpreted as signs of vascular tone or fluid deficit issues in patients. The ratio of the highest and lowest PI values yields the Pleth Variability Index (PVI) (3,4). PVI can be used to predict hypotension during anesthesia induction (5).
Cardiac output (CO) is calculated by multiplying systemic vascular resistance (SVR) and heart rate (HR). In septic and shock patients, CO may be low, often due to decreased SVR. The autonomic system tries to maintain CO by increasing HR in response to the reduced SVR (6). Systolic and diastolic shock indices are obtained by dividing the HR by systolic and diastolic blood pressures, respectively. The diastolic shock index has been evaluated in studies to predict vasopressor response in septic patients (7). A high shock index has been associated with early vasopressor initiation and better prognosis. However, no study has yet examined the predictive power of the diastolic shock index, which is related to sympathetic response and systemic vascular resistance, for hypotension following anesthesia induction.
Moreover, the diastolic shock index has not been compared with the more commonly used PVI in terms of their ability to predict hypotension. Therefore, our study aims to test the success of diastolic shock index and PVI measurements in predicting anesthesia-induced hypotension
1,003 studies on the registry are indexed under Hypotension; 173 are open to participants now.
This study's enrollment of 126 is above the median of 84 across 294 observational studies indexed under Hypotension.
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Patients who will undergo elective lumbar spine surgery in Kocaeli City Hospital operating rooms constitute the study universe.
Exclusion Criteria:
This group includes all study patients who underwent elective lumbar spine surgery under general anesthesia. In these patients, both PVI and DSI measurements will be performed before and during anesthesia induction.
Diagnostic Test: Pulse variability index measurement · Other: Diastolic shock index
Peripheral perfusion index (PI) is an easy-to-implement and low-cost monitoring procedure obtained by interpreting non-invasive data obtained from pulse oximetry via plethysmography. It is a tool that allows interpretation of fluid status through changes in pulse oximetry waves caused by respiration. High perfusion indices are interpreted as low arterial tone. Changes in perfusion index are interpreted as indicators of vascular tone or fluid deficit problems in patients. The ratio of the highest and lowest PI values gives the Pleth Variability Index (PVI) (3,4). Hypotension can be predicted during anesthesia induction with PVI
Also known as: PVI
The Diastolic Shock Index (DSI) is a hemodynamic parameter calculated by dividing the heart rate (HR) by the diastolic blood pressure (DBP). It reflects the balance between cardiac output and systemic vascular resistance, particularly in critically ill patients. A higher DSI can indicate impaired vascular resistance and may be useful for predicting the need for vasopressor support, especially in conditions like septic shock. However, its application in predicting hypotension during anesthesia induction is still under investigation.
Also known as: DSI
Prediction of anesthesia-induced hypotension
Anesthesia-induced hypotension is a significant drop in blood pressure that occurs during the induction or maintenance of anesthesia.Arterial hypotension was defined as systolic blood pressure (SBP) ; 90 mmHg in at least one measurement during this period or norepinephrine administered at a dose of ;6 mcg/min at lea
Time frame: First 20 minutes after induction of anesthesia
Plan to share: No — Sharing of patient data is prohibited by the institution and may be requested from the institution with appropriate request.
This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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Kocaeli City Hospital