Anesthesia, General
Conditions
Keywords
Intraoperative hypotention, Induction of anesthesia, Arterial blood pressure monitoring
Brief summary
Hypotension is common during surgery and about one-third of hypotension occur during the period from anesthesia induction to skin incision. Therefore, monitoring blood pressure during this period is crucial. Two methods are used for measuring blood pressure during surgery: the intermittent measurement method (oscillometric method) and the continuous measurement method (arterial catheterization method). The latter is frequently used in surgical patients who require meticulous hemodynamic management, although there is no clearly defined indication for its use. Despite the benefits of arterial catheterization, it is often delayed after induction of general anesthesia, and blood pressure is monitored intermittently using the oscillometric method. A recent study showed that continuous arterial pressure monitoring using arterial catheterization method during the induction of general anesthesia reduced hypotension significantly compared to 2.5-min interval intermittent arterial pressure monitoring using oscillometric method. The study was conducted on patients scheduled for continuous arterial pressure monitoring during surgery and the group with continuous arterial pressure monitoring showed significantly lower incidence of hypotension during the first 15 minutes of anesthesia induction. However, measuring blood pressure using the oscillometric method at 1-min interval, rather than 2.5-min interval, may not be significantly inferior to continuous monitoring via arterial catheterization in terms of hypotension occurrence. This study aims to compare hypotension incidence between arterial catheterization method and oscillometric method with 1-min interval during induction of anesthesia in non-cardiac surgery patients.
Interventions
DEVICE1-min interval oscillometric method
Before induction of anesthesia, 20-gauge catheter is inserted to radial artery after local anesthesia with lidocaine, and continuous blood pressure monitoring is started. Anesthesia is induced using propofol, opioids (fentanyl or remifentanil), and neuromuscular relaxants (rocuronium, cisatracurium, or vecuronium). For maintenance of anesthesia, propofol infusion or inhalation anesthetics (sevoflurane or desflurane) are used. From the start of anesthesia induction to 15 minutes after, arterial blood pressure is monitored at 1-min interval using oscillometric method. The display of continuous arterial pressure on the anesthesia monitor is turned off during the 15-min study period.
DEVICEarterial catheterization method
During the same time window for 1-min interval oscillometric method, arterial blood pressure is monitored using continuous blood pressure monitoring.
Sponsors
Seoul National University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult patients aged 19 or older undergoing scheduled non-cardiac surgery with general anesthesia and continuous invasive arterial blood pressure monitoring via the radial artery
Exclusion criteria
* Arterial access is clinically necessary before induction of anesthesia (e.g., moderate or higher degree of aortic stenosis, moderate or higher degree of heart failure, coronary artery disease requiring revascularization, intracranial aneurysm with a significant risk of rupture, etc.) * Emergency surgery * American Society of Anesthesiologists (ASA) physical status 5 or 6 * Arterial access is required in a different artery other than the radial artery (e.g., the femoral artery) * Electrocardiogram other than sinus rhythm * Refusal to participate in the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| MAP integral | From the start of anesthesia induction to 15 minutes after | The area under the mean arterial pressure (MAP) of 65 mmHg calculated using the MAP recorded every second |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Area under MAP of 60, 50, 40 mmHg (mmHg∙min) | From the start of anesthesia induction to 15 minutes after | calculated using the MAP recorded every second |
| Duration of MAP <65, <60, <50, <40 mmHg (min) | From the start of anesthesia induction to 15 minutes after | calculated using the MAP recorded every second |
| Exposure to MAP <65, <60, <50, and <40 mmHg (binary) | From the start of anesthesia induction to 15 minutes after | calculated using the MAP recorded every second |
| Exposure to continuous MAP <65, <60, <50, <40 mmHg for 1 minute or longer (binary) | From the start of anesthesia induction to 15 minutes after | calculated using the MAP recorded every second |
| Area above MBP of 100, 110, 120, 140 mmHg (mmHg∙min) | From the start of anesthesia induction to 15 minutes after | calculated using the MAP recorded every second |
| MAP standard deviation (mmHg) | From the start of anesthesia induction to 15 minutes after | calculated using the MAP recorded every second |
| Use of vasopressor (binary) | From the start of anesthesia induction to 15 minutes after | ephedrine, phenylephrine, norepinephrine (binary) |
| Use of vasopressor (dose) | From the start of anesthesia induction to 15 minutes after | ephedrine (mg), phenylephrine (μg/kg), norepinephrine (μg/kg) |
| Crystalloid (ml) | From the start of anesthesia induction to 15 minutes after | Total amount of crystalloid administered |
Countries
South Korea
Contacts
STUDY_DIRECTORKaram Nam, MD
Seoul National University Hospital
Outcome results
None listed