Section 1, 3, 6&7 Flashcards
Explain the term hypovolemia and 2 potential causes
This is the decrease in circulatory volume of the blood due to a haemorrhage or vomiting or diarrhoea
What is the clinical definition of shock
This is the lack of oxygen supply to cells resulting from a loss of blood resulting in reduced blood pressure
Explain the likely cause of the yellowish tinge in Phil’s eyes and skin
This is due to the build up of bilirubin. In liver failure, the amount of RBC broken down is reduced therefore causing a reduced production of bile. Reduced production of bile means that bilirubin cannot be secreted therefore leading to a build up known as jaundice
What is meant by the term ascites and what causes it?
This is the accumulation of fluid in the peritoneal cavity and occurs due to portal hypertension. It is formed due to loss of colloid osmotic pressure as the blood loses ability to hold water in the intravascular space causing it to leak into the surrounding interstitial space and because of the imbalance of electrolytes and plasma proteins such as albumin
Explain why Phil has been presented to A and E with periodic disorientation and how he is only responding to voice
This is due to the liver failure which has caused increased levels of ammonia. Protein is broken down into ammonia which in a healthy liver is converted into urea and therefore excreted by the kidneys. However in liver failure, the liver is unable to breakdown ammonia and therefore this molecule passes through the blood brain barrier into the cerebral fluid and cells which causes cerebral oedema and results in encephalopathy causing disorientation
Explain the likely cause of Phil’s haematemesis and how this has occured
This is due to the rapture of his varices caused by hypertension. Increased resistance to venous blood flow causes a back flow of pressure leading to portal hypertension greater than 10mmhg. Venous blood flow becomes diverted to collateral vessels when pressure builds up. The increase blood flow along the collateral vessels then causes them to become engorged leading to the development of varices. These varices present in the oesophagus, the fundus of the stomach and the fundus of the anus
Consider Phil’s chronic condition and current medication, why might Phil’s mild history of asthma now become a problem?
This is due to the use of beta-blockers (propanolol) which is a non-selective beta blocker and causes broncho constriction
Describe the pathological changes that have occurred to Phil’s liver as a result of his prolonged, excessive alcohol intake
Excess drinking causes scaring tissue and formation of fibrosis causing the liver to become harder and smaller. These changes in structure reduces the compliance of the liver and there is more blood flow from the portal vein into the liver. This resistance and increased blood flow causes the pressure to rise in the portal vein and is know as portal hypertension. Fatty acids also accumulate leading to fatty liver disease
Why has Phil lost weight and is noted to have muscle wastage?
In liver cirrhosis, the storage of glucose and glycogen is impaired. This means there is little glucose available for cells to use as ATP especially during times of stress. Therefore the fats and muscle reserves are broken down for alternative source of energy which causes muscle wastage and weight loss. Furthermore, toxins from alcohol stimulate the nausea and vomiting centre which can lead to poor oral intake
Why does Phil need vitamin K?
This is needed for the production of clotting factors and is usually derived from fats absorbed from diet. In Phil, the clotting time is extended which shows reduced clotting factors
Physiologically explain one potential benefit and one potential risk to Phil of his propranolol intake
It is a non selective beta blocker which works by reducing hypertension and by lowering cardiac output by blocking beta 1 receptors in the kidneys. Propanol can reduce BP and stop bleeding from his varices
In terms of it’s action, how is chlodiazepoxide of therapeutic benefit to Phil?
Due to it’s sedative, anxiety and muscle relaxing effect, it helps Phil during the period of his alcohol withdrawal. It works on GABA receptors in the brain. GABA are neurotransmitters that act as natural nerve calming agents and are involved in reducing anxiety and stress during alcohol withdrawal.
In terms of it’s action, explain why Phil was prescribed Terlipressin
This is to treat his variceal bleed. Due to it’s vasopressin action, terlipressin will bind to the vasopressin receptors causing arteriole vasoconstriction. It also has a stronger action to splenic arteriole system by causing vasoconstriction hence reducing portal hypertension therefore reducing the risk of a further variceal bleed which was noted when he was admitted
One common side effect of chlordiazepoxide
Insomnia
Hallucinating
Depression
Why has Phil been prescribed Lactulose, explain according to it’s action
It is an osmotic diuretic which increases the quantity of water in the large intestine by drawing fluid from the body which also pulls ammonia hence reducing the concentration of ammonia in the brain. This helps with Phil’s encephalopathy
