Lecture 2 part 1 Flashcards
What part of the brain controls breathing?
The respiratory centre situated in the brain stem, this relies upon chemical and neurological input.
What are the 2 phases of breathing?
Inspiration and expiration
What is Inspiration?
Movement of air into the lung, contraction of diaphragm expands thoracic chamber and negative pressure increases lung volume sucking in air to fill the space. Requires energy
What is Expiration?
Movement of air out of lungs, positive pressure, passive (no energy in normal circumstance, elastic recoil returns to resting state.
What is external respiration?
Exchange of gases between the alveoli of the lungs and the pulmonary blood capillaries
What is Internal respiration?
Exchange of oxygen and carbon dioxide between the systemic blood capillaries and the tissue cells.
Define: Tachypnoea
Abnormally rapid breathing (>20) is usually first indication of respitary distress
Define:Bradypnoea
Abnormally slow rate of breathing (>12) can indicate severe deteriation in pt condition. Possible causes: fatigue, hypothermia, CNS depression, opiate drugs
Define: Orthopnoea
Condition where a patient must stand/sit-up in order to breathe comfortably. (asthma, pulmonary oedema, emphysema)
Define: Cheyne stokes
Respiratory pattern – periods of apnea alternated with periods of hyperapnoea. (LVF, cerebral injury, end stage of life)
Define: Kussmaul Breathing
– (Air hunger) – deep rapid resps due to stimulation of respiratory centre in brain caused by metabolic acidosis
What is peripheral cyanosis?
Inadequate oxygenation of the circulating blood. Peripherals appear blue (tongue and lips pink)
What is Central cyanosis?
Systemic shortage of Oxygen (more serious then peripheral), detectable when arterial O2 sat <85%. (causes: Pneumonia, acute severe asthma, pulmonary oedema, PE)
