An interventional study of Crystalloid Solutions in Hypotension Drug-Induced and Anesthesia, sponsored by Medical University of Graz. Active, not recruiting at 2 sites in Austria. Open to participants aged 45 Years and older. Per ClinicalTrials.gov, last updated 2025-11-21.
Sponsored by Medical University of Graz · Not applicable, Interventional, and Treatment
Theoretical framework:
Hypotension during surgery directly impacts patients' postoperative outcomes and complications. Decrease in blood pressure measurements secondary to anesthetic drugs is an expected scenario in most surgical cases. Moreover, hypovolemia secondary to fast pre-operative period may facilitate post-induction hypotension which can be compensated by fluid bolus pre-operatively.
Objectives:
The purpose of the study is to conduct a randomized intervention cohort study using pre-operative fluid therapy to assess its effect on blood pressure during the post-induction period. The investigators are testing the hypothesis that preoperative Crystalloid bolus decreases the risk of post-induction hypotension, specifically the time-weighted average (TWA) mean arterial pressure (MAP) under 65 mmHg during the first 20 minutes after anaesthetic induction or until surgical incision, whichever is first, compared to standard of care, which is minimal fluid administration in the pre-operative period.
Methods:
The investigators will conduct a randomized intervention cohort study using pre-operative fluid therapy to assess its effect on blood pressure during the post-induction period. The intervention group will receive a bolus of a balanced crystalloid solution within 60 ± 15 minutes before induction of anaesthesia. The control group will be treated according to the current clinical standard of care. The investigators will compare the time-weighted average (TWA) mean arterial pressure (MAP) under 65 mmHg during the first 20 minutes after anaesthetic induction or until surgical incision (whichever comes first).
1,003 studies on the registry are indexed under Hypotension; 173 are open to participants now.
This study's enrollment of 550 is above the median of 80 across 675 interventional studies indexed under Hypotension.
Browse Hypotension studies →Medical University of Graz is the lead sponsor of 459 studies on the registry; 98 are open to participants now.
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Subject to at least one of the following risk factors:
Exclusion Criteria:
The investigators will start a balanced crystalloid solution (in detail we will administer 500ml if the actual body weight is ≤90 kg: the investigators will administer 1000 ml if the actual body weight is \>90 kg:) within 60 +/- 15 minutes before induction of anesthesia in the pre-operative area or at the ward, as appropriate.
Other: Crystalloid Solutions
Patients will receive the balanced crystalloid solution according to the current clinical standard of care.
As above
Post-induction MAP
Post-induction hypotension is defined as TWA MAP under 65 mmHg during post-induction period. We will use non-invasive continuous arterial blood pressure monitoring as feasible. Anesthesia staff and nurses will be blinded, and standard of care will be provided. Data from the monitor will be recorded in the anesthesia record. We will be using standard intraoperative patient monitoring system. This system will measure 3 lead ECG (electrocardiogram), SpO2 (Arterial oxygen saturation), and number of respirations continuously. The primary outcome will be the TWA MAP under 65 mmHg during the post-induction period.
Time frame: 60 +/- 15 minutes before induction of anesthesia until the first 20 minutes after anesthetic induction or until surgical incision (whichever comes first)
Vasopressors
The major outcome for the vasopressor requirement will be a binary variable representing the use of vasopressors during the post-induction period. Additionally, we will compare the amount of vasopressors between the groups.
Time frame: 60 +/- 15 minutes before induction of anesthesia until the first 20 minutes after anesthetic induction or until surgical incision (whichever comes first)
Cardiac Output (CO)
The major outcome for the non-invasively measured CO will be a continuous measurement throughout pre-induction, induction of anesthesia and post-induction as feasible.
Time frame: 60 +/- 15 minutes before induction of anesthesia until the first 20 minutes after anesthetic induction or until surgical incision (whichever comes first)
Plan to share: Yes — For electronic data management we will use the CLINCASE software (Quadratek, Berlin, Germany). Data storage and back up will be provided by IT Systems \& Communications (ITSC) - IT4Science (Medical University of Vienna). Access to data is strictly controlled and will only be provided to the Sponsor (Medical University of Graz and the Medical University of Vienna), the study investigators and the ethic commission (Ethic commission of the Medical University of Vienna). All entries and changes in the CLINCASE software will be tracked.
Supporting information: Study protocol, Sap, Icf, Csr, Analytic code
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.
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Medical University of Graz