Q. What causes blood velocity to increase when blood goes from the capillaries to the veins?
A. energy, mass and momentum are conserved even as the vessels norrow, so to make up for the decreased area, the blood picks up speed. it can be shown by the equation A1V1=A2V2
A is area
V is velocity.
the more you narrow the vessel the faster it is going to go. It is kinda of like when you have a hose, and then you put your finger to restrict the flow, the water shoots out at a much greater velocity and distance.
A is area
V is velocity.
the more you narrow the vessel the faster it is going to go. It is kinda of like when you have a hose, and then you put your finger to restrict the flow, the water shoots out at a much greater velocity and distance.
How long can blood stay in a tube before being tested for blood alcohol level?
Q. Blood was drawn into a test tube but lab is closed and can't be tested until tomorrow. Will it still be accurate?
A. You have 14 days per below:
__________________________________
Whole blood or serum
Volume: 7 mL
Minimum Volume: 0.5 mL
Container: Gray-top (sodium fluoride) tube (preferred) or red-top tube. Submit original unopened tube.
Special Instructions: Do not prepare venipuncture site with alcohol or remove stopper from tube.
Storage Instructions: Refrigerate
Stability: Temperature Period
Room temperature 14 days
Refrigerated 14 days
Frozen 14 days
Freeze/thaw cycles Stable x3
Reference Interval: Negative (cutoff = 0.010%)
Use: Quantitation of alcohol level for medical or legal purposes; test unconscious patients; used to diagnose alcohol intoxication and determine appropriate therapy; detect alcoholism and to monitor ethanol treatment for methanol intoxication. Must be tested as possible cause of coma of unknown etiology since alcohol intoxication may mimic diabetic coma, cerebral trauma, and drug overdose.
Methodology: Gas chromatography (GC)
Additional Information: Ethanol is absorbed rapidly from the GI tract. Peak blood levels usually occur within 40 to 70 minutes on an empty stomach. Food in the stomach can decrease the absorption of alcohol. Ethanol is metabolized by the liver to acetaldehyde. Once peak blood ethanol levels are reached, disappearance is linear; a 70 kg man metabolizes 7-10 g of alcohol/hour (15±5 mg/dL/hour). The urine:blood ratio is considered to be about 1.35:1 but is quite variable. The average saliva:blood ratio is 1:20. Symptoms of intoxication in the presence of low alcohol levels could indicate a serious acute medical problem requiring immediate attention. The half-lives and effectiveness of certain drugs (eg, barbiturates, etc) are increased in the presence of ethanol.
__________________________________
Whole blood or serum
Volume: 7 mL
Minimum Volume: 0.5 mL
Container: Gray-top (sodium fluoride) tube (preferred) or red-top tube. Submit original unopened tube.
Special Instructions: Do not prepare venipuncture site with alcohol or remove stopper from tube.
Storage Instructions: Refrigerate
Stability: Temperature Period
Room temperature 14 days
Refrigerated 14 days
Frozen 14 days
Freeze/thaw cycles Stable x3
Reference Interval: Negative (cutoff = 0.010%)
Use: Quantitation of alcohol level for medical or legal purposes; test unconscious patients; used to diagnose alcohol intoxication and determine appropriate therapy; detect alcoholism and to monitor ethanol treatment for methanol intoxication. Must be tested as possible cause of coma of unknown etiology since alcohol intoxication may mimic diabetic coma, cerebral trauma, and drug overdose.
Methodology: Gas chromatography (GC)
Additional Information: Ethanol is absorbed rapidly from the GI tract. Peak blood levels usually occur within 40 to 70 minutes on an empty stomach. Food in the stomach can decrease the absorption of alcohol. Ethanol is metabolized by the liver to acetaldehyde. Once peak blood ethanol levels are reached, disappearance is linear; a 70 kg man metabolizes 7-10 g of alcohol/hour (15±5 mg/dL/hour). The urine:blood ratio is considered to be about 1.35:1 but is quite variable. The average saliva:blood ratio is 1:20. Symptoms of intoxication in the presence of low alcohol levels could indicate a serious acute medical problem requiring immediate attention. The half-lives and effectiveness of certain drugs (eg, barbiturates, etc) are increased in the presence of ethanol.
18. What is �blood typing�? How is it done? Why is it so important to run blood typing before a blood transfus?
Q. 18. What is �blood typing�? How is it done? Why is it so important to run blood typing before a blood transfusion? What happens if mom and baby have different blood types?
A. Blood typing is determining the antigens present on a red blood cell.
In a clinical setting, blood type is determined by mixing red blood cells with in three different tubes. One with anti-A antibodies, one with anti-B antibodies, and another with anti-D antibodies. This determines the forward type. The person's plasma (the liquid portion of blood) is mixed in two other tubes, one with type A red blood cells, and the other with type B red blood cells to determine the reverse or back type. Agglutination (red cells clumping) indicates a reaction between antigen and antibody. So if there is agglutination in the tubes of anti-A, anti-D, and B red blood cells, the person is A+.
It is important to determine the blood type because of the antibodies that are present to ABO blood group antigens that are not present on the person's red blood cells. For example, type A individuals are expected to produce anti-B antibodies. If you transfuse blood that has one of the antigens that the body has made antibodies toward, the antibodies will attach to the transfused red blood cells and hemolyze them. The resulting reaction can cause death.
If mom and baby have different blood types there is a chance that the mom's antibodies cross the placenta and start destroying the baby's red blood cells. In mild cases it will cause increased bilirubin levels after birth. In severe cases it could cause death of the baby if there is no intervention. ABO incompatibilities between mother and baby rarely cause major problems.
In a clinical setting, blood type is determined by mixing red blood cells with in three different tubes. One with anti-A antibodies, one with anti-B antibodies, and another with anti-D antibodies. This determines the forward type. The person's plasma (the liquid portion of blood) is mixed in two other tubes, one with type A red blood cells, and the other with type B red blood cells to determine the reverse or back type. Agglutination (red cells clumping) indicates a reaction between antigen and antibody. So if there is agglutination in the tubes of anti-A, anti-D, and B red blood cells, the person is A+.
It is important to determine the blood type because of the antibodies that are present to ABO blood group antigens that are not present on the person's red blood cells. For example, type A individuals are expected to produce anti-B antibodies. If you transfuse blood that has one of the antigens that the body has made antibodies toward, the antibodies will attach to the transfused red blood cells and hemolyze them. The resulting reaction can cause death.
If mom and baby have different blood types there is a chance that the mom's antibodies cross the placenta and start destroying the baby's red blood cells. In mild cases it will cause increased bilirubin levels after birth. In severe cases it could cause death of the baby if there is no intervention. ABO incompatibilities between mother and baby rarely cause major problems.
What should purified blood contain after being filtered in the kidneys?
Q. when blood is filtered in the kidney and then back in the renal vein, what should that blood contain?
A. Blood proteins. They are too large to filter through the fenstrated endothelium of of glomerulus in the kidney nephrons.
EDIT: In addition the blood will contain hemoglobin and anything else that is the same size or larger than a red blood cell.
EDIT: In addition the blood will contain hemoglobin and anything else that is the same size or larger than a red blood cell.
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