Clinical Measurement Flashcards
What is clinical measurement?
Clinical measurement is the development, use, on-going support, and maintenance of technology for diagnosing, aiding or treating patients.
What is vomiting?
Vomiting involves the forceful movement and elimination of the contents of the stomach by the constant action of the abdominal muscles with the opening of the gastric cardia.
What causes vomiting?
- Dehydration
- Nutritional deficiencies
- Electrolyte and acid-base imbalance
- Toxins
- Metabolic conditions
- Organ failure/ disorders of viscera
- Neurological conditions
What two areas are associated with the pathophysiology of vomiting?
- The pathophysiology of nausea and vomiting is complex. The act of emesis is associated with 2 main centres located in the medulla oblongata (the brain stem)
- The vomiting centre
- The chemoreceptor trigger zone (CTZ)
What is CTZ (vomiting)?
- Chemoreceptor trigger zone
- The CTZ is an area of the brain not fully separated from the blood by the blood brain barrier so it can detect chemicals in the blood and cerebrospinal fluid and initiate vomiting.
- The CTZ is also stimulated by signals from the gut to the inner ear
What are the two general mechanisms for vomiting?
Neurological and peripheral
What is the physiology of vomiting in the brain?
Brain area- Medulla Oblongata- Centre of MO is called vomiting centre-> muscarinic receptor gets stimulated= vomiting reflex
What is the physiology of vomiting in the CTZ?
Near the MO is chemoreceptor trigger zone (CTZ) is chemically stimulated- has 5 HT and dopamine 2 receptors- chemotherapy can trigger CTZ= CTZ triggers MO vomiting centre= vomiting
What is the physiology of vomiting in the ear?
Motion sickness- labyrinth in inner ear
What is the neurological mechanism of vomiting?
- Stimulation of the Medulla Oblongata (within the brain stem) which ‘senses’ noxious chemical agents e.g poisons, chemotherapy agents, digoxin, causing nausea and the emesis reflex (vomiting)
- Diseases of the central nervous system (brain and spinal cord) such as infections or tumours which stimulate structures within CNS to elicit nausea and vomiting
What is the peripheral mechanism of vomiting?
- Diseases such as those of the gastrointestinal (GI) tract. Brain centres where nausea is perceived stimulate vomiting
- Tumours, infections or drugs in the periphery may cause local dysfunction, in a variety of organ systems that is sensed as nausea that, when severe causes vomiting
What toxins cause vomiting?
- Medications/drugs e.g cytoxics, opioids, NSAIDs, antibiotics, anticonvulsants, iron and many others
- Poisoning
- Substance abuse
What metabolic conditions cause vomiting?
- Hypercalcaemia
- Hyponatremia
- Ketoacidosis
What is hypercalcaemia?
A condition in which the calcium level in your blood is above normal. Too much calcium in your blood can weaken your bones, create kidney stones, and interfere with how your heart and brain work. Hypercalcemia is usually a result of overactive parathyroid glands.
What is hyponatremia?
Hyponatremia means that the sodium level in the blood is below normal. When the sodium level in your blood is too low, extra water goes into your cells and makes them swell. This swelling can be dangerous especially in the brain, since the brain cannot expand past the skull.
What is ketoacidosis?
Diabetic ketoacidosis (DKA) is a serious problem that can happen in people with diabetes if their body starts to run out of insulin. When this happens, harmful substances called ketones build up in the body, which can be life-threatening if it’s not found and treated quickly.
What organ failure/ viscera disorders cause vomiting?
- Liver
- IBS (VD)
- Renel obstruction e.g gastric outlet, bowel, biliary, pancreatic
- Severe constipation
- Gastroparesis inflammation or irritation e.g gastroenteritis
- Hepatitis
- Cholecystitis- inflammation of the gallbladder
- NSAID- Non-steroidal anti-inflammatory drugs
- Chemotherapy (radiation)
- Malignancy- the state or presence of a malignant tumour; cancer
- Ascites- Ascites is the abnormal buildup of fluid in the abdomen
What is a viscera disorder?
Visceral pain, defined as pain originating from the internal organs, is a hallmark feature of multiple diseases, including inflammatory bowel disease, pancreatitis, irritable bowel syndrome (IBS), and functional dyspepsia.
What neurological conditions cause vomiting?
- Increased intracranial pressure e.g malignancy, haemorrhage, cranial irradiation or abscess
- Meningeal infiltration
- Vestibular e.g labyrinthitis or effects of medications/drugs
- Anxiety
- Pain
What is haematemesis?
Presence of blood in vomit, bright pink or ‘coffee ground’
What is copraemesis?
Odour or presence of faeces in vomit
What is retching?
Movements associated with vomiting without the expulsion of gastrointestinal contents