Blood Volume, Extravasation
Conditions
Keywords
blood volume
Brief summary
In patients undergoing extracorporal circulation during cardiac operation, the hemoglobin is subjected to large changes. The purpose of this study is to see if it is possible with the help of volume kinetic techniques to use these variations to measure blood volume and fluid escape from the intravascular volume.
Detailed description
In many clinical situations, such as extensive surgery, it is of value to determine blood volume and rate of fluid loss from the intravascular space, since hypo- and hypervolemia are combined with increased morbidity and mortality. In this study we which to use the large variations in hemoglobin during extracorporal to calculate both these variables. Hemoglobin is measured every 5 minutes during one hour beginning shortly before start of the heart-lung machine. When the extracorporal circulation begins the hemoglobin decreases due to the quick mix and dilution of the priming fluid from the heart-lung machine with the patients blood. From the amount of priming fluid and the fall of the hemoglobin, the blood volume can be calculated. If no further fluid is given the next 20 to 30 minutes, the hemoglobin concentration will in most cases increase as a result of the fluid loss from the vascular space. This increase in combination with the diureses can be used to calculate the intravascular fluid loss to the interstitium during surgery. Sodium concentration will also be measured in parallel with the hemoglobin concentration. The Sodium concentrations in combination with given and excreted (urine)Sodium can be used in a mass balance to calculate if intracellular edema is induced.
Interventions
None listed
Sponsors
University Hospital, Linkoeping
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* open heart surgery, with extracorporal circulation * consent to participation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Blood Volume | 30 minutes after start of CPB | volume kinetic technique: During start of cardio pulmonary by-pass a known amount of fluid will expand the blood volume and dilute the hemoglobin. 1. The hemoglobin variation is used to calculate the blood volume. The last hemoglobin value before CPB and the hemoglobin value directly after start (extrapolated from the following 30 minutes after start) of CPB are used in the calculation. 2. The value for the blood volume directly prior to CPB will be influenced by intra venous fluids given during early stages of the anesthesia. To achieve the blood volume prior to anesthesia a hemoglobin value before anesthesia and the last hemoglobin value before CPB are used to correct the blood volume calculation. In this way blood volume prior to anaesthesia can be calculated. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intracellular Edema | 30 minutes after CPB | Mass balance based on repeated Sodium concentration, fluid volume given, given and excreted Sodium. A positive value indicating intracellular fluid accumulation and a negative value indicating cell dehydration. This is the change that will occur during the first 30 min after start of cardio pulmonary bypass. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Fluid Extravasation | Two distribution half-times. Approximately 16 minutes. | Rate of fluid transfer from the intravascular to the extravascular compartment during two distribution half-times. Graph derived from the hemoglobin change during 20 to 30 minutes after start of cardio pulmonary by-pass. |
Countries
Sweden
Participant flow
Recruitment details
January 2010 to September 2010 at thoracic surgery department
Pre-assignment details
Included patients (10). All participated in the study.
Participants by arm
| Arm | Count |
|---|---|
| Cardiac Surgery Patients subjected to open cardiac surgery with the help of extracorporal circulation. | 10 |
| Total | 10 |
Baseline characteristics
| Characteristic | Cardiac Surgery |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 8 Participants |
| Age, Categorical Between 18 and 65 years | 2 Participants |
| Age Continuous | 71.1 years STANDARD_DEVIATION 11.6 |
| Region of Enrollment Sweden | 10 participants |
| Sex: Female, Male Female | 2 Participants |
| Sex: Female, Male Male | 8 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 10 |
| serious Total, serious adverse events | 0 / 10 |
Outcome results
Primary
Blood Volume
volume kinetic technique: During start of cardio pulmonary by-pass a known amount of fluid will expand the blood volume and dilute the hemoglobin. 1. The hemoglobin variation is used to calculate the blood volume. The last hemoglobin value before CPB and the hemoglobin value directly after start (extrapolated from the following 30 minutes after start) of CPB are used in the calculation. 2. The value for the blood volume directly prior to CPB will be influenced by intra venous fluids given during early stages of the anesthesia. To achieve the blood volume prior to anesthesia a hemoglobin value before anesthesia and the last hemoglobin value before CPB are used to correct the blood volume calculation. In this way blood volume prior to anaesthesia can be calculated.
Time frame: 30 minutes after start of CPB
Population: The study was mainly an observational study, and 10 patients was regarded as a sufficient number to register general changes.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Cardiac Surgery | Blood Volume | 4.61 Litre | Standard Deviation 0.86 |
Secondary
Intracellular Edema
Mass balance based on repeated Sodium concentration, fluid volume given, given and excreted Sodium. A positive value indicating intracellular fluid accumulation and a negative value indicating cell dehydration. This is the change that will occur during the first 30 min after start of cardio pulmonary bypass.
Time frame: 30 minutes after CPB
Population: Mainly observational. 10 patients were regarded to be a sufficient number to se a tendency.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Cardiac Surgery | Intracellular Edema | -0.33 Litre | Standard Deviation 0.557 |
Other Pre-specified
Fluid Extravasation
Rate of fluid transfer from the intravascular to the extravascular compartment during two distribution half-times. Graph derived from the hemoglobin change during 20 to 30 minutes after start of cardio pulmonary by-pass.
Time frame: Two distribution half-times. Approximately 16 minutes.
Population: The study was mainly an observational study, and 10 patients was regarded as a sufficient number to register general changes.
| Arm | Measure | Value (MEDIAN) | Dispersion |
|---|---|---|---|
| Cardiac Surgery | Fluid Extravasation | 0.38 mL/kg/min | Standard Deviation 0.24 |