Running Repairs Flashcards
Hole in the Heart
- The heart cannot work properly with a hole in the wall between the two sides of the heart.
- This can be corrected by ‘open heart’ surgery.
- A ‘hole in the heart’ allows blood to flow from one side of the heart to the other, so blood leaving the heart in the aorta carries less than the usual amount of oxygen, causing muscles to have less oxygen and therefore less energy.
What does a hole in the heart cause?
A ‘hole in the heart’ causes mixing of oxygenated and deoxygenated blood, resulting in the arterial blood carrying less oxygen.
How is the circulation of a unborn different?
- The circulation in an unborn baby is different from its circulation after it is born since the lungs do not function until it is born.
- An unborn baby therefore does not need a double circulatory system.
- Before birth, a hole exists between the two sides of the heart which closes at birth.
When can the heart not work?
- The heart cannot work properly with damaged or weak valves.
- They can be repaired or replaced by surgery.
- A heart with damaged or weak valves produces a lower blood pressure and poor blood circulation, as blood will leak backwards.
What happens when the coronary artery is blocked?
- A blocked coronary artery reduces the blood flow to the heart muscles.
- It can be by-passed by transplanting a blood vessel from another part of the body.
How can major heart problems be corrected?
- Major heart problems can be corrected by transplanting donor hearts.
- Small electrical pumps (heart assist devices) can be also be used to provide extra pressure to blood leaving the heart, so allowing time for damaged muscles to recover.
What are the advantages and disadvantages of artificial pacemakers artificial valves?
- Artificial Pacemakers and artificial valves have obvious advantages of keeping patients alive and improving their quality of life.
- There are also no problems of donor shortages and finding tissue matches.
- Surgery carries a risk, especially the major surgery of a heart transplant.
- Preventing rejection of a transplant also involves lifetime use of immuno-suppressive drugs.
What do blood donation involve?
Blood donations involves the collection of blood from the volunteer. Anti-coagulant drugs such as heparin are used and the blood group and rhesus information is recorded.
Blood transfusion
A blood transfusion puts the correct blood type into the patient’s blood system, replacing blood lost after an accident or operation.
Drug for preventing clotting
Doctors can use drugs such as warfarin, heparin, and aspirin to prevent clotting, which can block blood vessels in some medical condition.
Haemophillia
People with the inherited condition haemophilia are at risk of internal bleeding from the slightest knock, as the blood does not clot.
Process of blood clotting
- The process of blood clotting is called a cascade process as it involves many steps.
- When blood platelets are exposed to the air at a wound site,
- it triggers a complex sequence of chemical reactions,
- eventually leading to the formation of a meshwork of fibrin fibres (clot).
Agglutination
A reaction called agglutination (bloodclumping) takes place when different blood groups are incompatible. When agglutins in red blood cells and blood plasma reacts, the blood transfusion endangers the patients life.
Agglutins
- Agglutins are:
- Two proteins: antigen A or antigen B on the surface of red blood cells
- Two antibodies: anti-A or anti-B in blood plasma.
- Antigen A will react with anti-A, and antigen B will react with anti-B, causing agglutination.
- Antigen A does not react with anti-B and antigen B does not react with anti-A.
Group A has:
- Antigen A and antibody B
- Donates to A, AB
- Receives from A, O
