Conditions: Blood Volume Blood Coagulation
Keywords: Blood volume blood coagulation volume kinetics
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 10
Healthy volunteers: yes

Brief summary:
Volume kinetics is a method mostly used, so far, to study the distribution and elimination of crystalloid solutions. Voluven (in Sweden the most commonly used colloid for replacement of bleeding during surgery) is poorly studied, though. Also, a recent study showed unexpected volume kinetics for a crystalloid solution when it was given after a colloid solution. The investigators aim to study the volume kinetics of crystalloids and colloids and also the combination of the two in more detail. The investigators will also compare the invasive hemoglobin measurements with measurements from a new non-invasive tool (Radical 7, from Masimo Inc.) which could help to make volume kinetics more practical for everyday use. Finally the investigators will also study the concentrations of a few coagulation factors to see if they can explain the variations in coagulability that has been described in earlier studies of infusion solutions.

Detailed description:
We will study ten volunteers, each one on three occasions. Each volunteer will receive only crystalloid one time, only colloid another time, and on the third occasion first a colloid and then a crystalloid one hour later. The different protocols will be in random order in the different volunteers. During all these tests we will sample the hemoglobin (both invasive and non-invasive) every fifth minute in the beginning (every tenth minute later) after the infusion. On six to nine occasions during each test we will analyse Albumin, Cystatin-C, Ig-G, Ig-M as markers of hemodilution and D-Dimer, Fibrinogen, Factor VII, PK-INR (prothrombin complex international normalized ratio), and aPTT (activated partial thromboplastin time) as markers of coagulation. The volunteers are also monitored regarding non-invasive blood pressure and pulse rate.

Arms:
arm 1: First intervention: A. acetated Ringers 20 ml/kg bodyweight during 30 minutes followed by 150 minutes of equilibration, when blood samples were collected.

Washout \>7 days

Second intervention: B. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed by 390 minutes of equilibration and blood samples.

Washout \> 7 Days

Third intervention: C. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed 90 minutes later by acetated Ringers 20 ml/kg bodyweight during 30 minutes. thereafter the subjects stayed for Another 285 minutes of equilibration and blood samples. arm 2: First intervention: A. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed by 390 minutes of equilibration and blood samples.

Washout \>7 days

Second intervention: B. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed 90 minutes later by acetated Ringers 20 ml/kg bodyweight during 30 minutes. thereafter the subjects stayed for Another 285 minutes of equilibration and blood samples.

Washout \> 7 Days

Third intervention: C. acetated Ringers 20 ml/kg bodyweight during 30 minutes followed by150 minutes of equilibration, when blood samples were collected. arm 3: First intervention: A. acetated Ringers 20 ml/kg bodyweight during 30 minutes followed by150 minutes of equilibration, when blood samples were collected.

Washout \>7 days

Second intervention: B.Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed 90 minutes later by acetated Ringers 20 ml/kg bodyweight during 30 minutes. thereafter the subjects stayed for Another 285 minutes of equilibration and blood samples.

Washout \> 7 Days

Third intervention: C. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed by 390 minutes of equilibration and blood samples. arm 4: First intervention: A. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed by 390 minutes of equilibration and blood samples.acetated Ringers 20 ml/kg bodyweight during 30 minutes followed by150 minutes of equilibration, when blood samples were collected.

Washout \>7 days

Second intervention: B. acetated Ringers 20 ml/kg bodyweight during 30 minutes followed by150 minutes of equilibration, when blood samples were collected.

Washout \> 7 Days

Third intervention: C. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed 90 minutes later by acetated Ringers 20 ml/kg bodyweight during 30 minutes. thereafter the subjects stayed for Another 285 minutes of equilibration and blood samples. arm 5: First intervention: A. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed 90 minutes later by acetated Ringers 20 ml/kg bodyweight during 30 minutes. thereafter the subjects stayed for Another 285 minutes of equilibration and blood samples.

Washout \>7 days

Second intervention: B. Voluven 6 % (starch solution) 10 ml/kg bodyweight during 30 minutes followed by 390 minutes of equilibration and blood samples.

Washout \> 7 Days

Third intervention: C. acetated Ringers 20 ml/kg bodyweight during 30 minutes followed by150 minutes of equilibration, when blood samples were collected.

Interventions: intervention 1: acetated Ringers intervention 2: colloid intervention 3: colloid+acetated Ringer intervention 4: Non-invasive hemoglobin with pulse-oximeter (SpHb)
Intervention descriptions: intervention 1: Infusion of Ringer acetate 20 ml/kg over 30 min intervention 2: Infusion of starch 10 ml/kg over 30 min intervention 3: Infusion of combined colloid+acetated Ringer; 10 ml/kg of starch was infused between 0 and 30 min, followed by 20 ml/kg of Ringers acetate between 105 and 135 min. intervention 4: Non-invasive hemoglobin with pulse-oximeter (SpHb) was measured in all subjects, during all infusions.

Protocol document: