Anesthesia, Blood Pressure, Hematocrit Change
Conditions
Keywords
Anesthesia, Blood pressure, Plasma volume, Vasopressor agents, Continuous noninvasive hemoglobin measurement, Coronary artery bypass
Brief summary
The arterial blood pressure affects the ratio between filtration and reabsorption of fluids in the circulating blood volume and thereby the hematocrit. During induction of anesthesia blood pressure, hemoglobin level and hematocrit decreases. The aim of the study is to evaluate weather a maintained blood pressure with norepinephrine during anesthesia induction reduces the decrease in hematocrit.
Detailed description
24 patients scheduled for coronary artery bypass surgery will be included and randomized to receive either norepinephrine in the dose needed to maintain pre-anesthesia blood pressure or to a control group and receive norepinephrine only if mean arterial pressure decreases below 60 mmHg. Arterial blood gas will be analysed every ten minutes. Equal anesthesia in both groups will be monitored. No fluids will be infused. Noninvasive continuous hemoglobin measurement (SpHb) will be measured.
Interventions
PROCEDUREMaintained blood pressure
Norepinephrine therapy to maintain preanesthesia blood pressure
DRUGNorepinephrine
Norepinephrine therapy to maintain preanesthesia blood pressure
Sponsors
Sahlgrenska University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Elective coronary artery surgery patients
Exclusion criteria
* Age under 18 years * untreated hypertension * a reduced left ventricular systolic ejection fraction of 45 % or less * diabetes mellitus * former stroke and/or a known carotid artery stenosis.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The magnitude and dynamics of the decrease in hematocrit during anesthesia induction | 70 minutes from anesthesia induction |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Reduced hematocrit decrease by vasopressor infusion maintained blood pressure | 70 minutes from anesthesia induction | To assess if the decrease in hematocrit can be reduced, by maintaining the blood pressure with vasopressor infusion |
Other
| Measure | Time frame | Description |
|---|---|---|
| Accuracy of continuous non-invasive hemoglobin monitoring (SpHb) to invasive Hb levels | 70 minutes from anesthesia induction | To evaluate if changes in invasive measured Hb levels, can be measured by continuous non-invasive hemoglobin monitoring (SpHb). |
Countries
Sweden
Contacts
Primary ContactTor Damén, MD
Backup ContactAndreas Nygren, MD
Outcome results
None listed