Resp II

Mechanics of respiration

3

• inhalation

• exhalation (expiration)

• gas exchange

inhalation

• active process

• muscles

  • contract to elevate rib cage

  • allows thoracic cavity to increase in size

  • decreasing in pressure

  • air flows in lungs to inflate

• diaphragm

  • moves caudally and ventrally

• external intercostals

• others

  • scalenus, serratus ventralis and dorsalis, external abdominal oblique 

exhalation (expiration)

• usually passive

  • muscles relax, decrease thoracic size, increase pressure, air flows out, lungs deflate

• forced exhalation = active

  • internal intercostals, abdominal and other muscles

gas exchange

• governed by partial pressure of gases 

  • same as concentration gradient

  • low to high concentration

  • gaw laws

  • gases in alveolar air, alveolar capillaries, body cells, body capillaries

hemoglobin

carries O2

also likes to carry CO

control of respiration

6

• medulla oblongata 

• chemoreceptors

• parasympathetic

• sympathetic

• reflexes

• carotid and aortic bodies

medulla oblongata

• respiratory center

chemoreceptors

• for H

• interstitial fluid and CSF

• detect O2 and CO2

• regulates breathing pattern

  • rhythmic breathing pattern

  • respiratory rate

  • deepness of breath

parasympathetic

• resting

• Vagus

• bronchoconstriction

  • doesn't need more O2

  • wants O2 in tissue and organs

sympathetic

• fight or light

• bronchodilation

  • wants more O2 for heart, lungs, and skeletal muscles

carotid and aortic bodies

• chemoreceptors for CO2, O2, and H

  • increased CO2

  • H build up

    • more acidic

      • sends signals to medulla oblongata to increases RR and depth

  related to acid/base balance

reflexes

inflation of lungs stimulates receptors in lungs

skin receptors

• important in newborns

• lick newbon/rub with towel

• excitatory 

upper airways

• mucous membrane stimulation

  • stimulates CN V Trigeminal

    • swallowing, sneezing, and coughing

    • protective

diving reflexes

• bobbing for apples

• protective reflex

  • responds to low levels of oxygen

  • slows down Hr, peripheral vasoconstriction

acid base disturbances

• disturbances in the pH of body fluids can contribute significantly to the morbidity and mortality associated with a variety of diseases 

• body uses buffer systems to regulate pH

• respiratory acidosis

• respiratory alkalosis

• respiratory compensation

maintenance of pH is critical for normal homeostasis

• pH = H concentration

  • too much H

    • acidic

  • too little h

    • basic

• for most animals pH is maintained at 7.4

  • 6.8-7.8

body uses buffer systems to regulate pH

• bicarbonate system

  • lungs regulate CO2

    • net pH change can happen quickly

  • kidneys regulate HCO3 and H

    • H excreted in urine and NH4 and HCO3 is conserved

    • net pH change can take days to occur

respiratory acidosis

def

• respiratory diseases which result in decreased ventilation

  • hypoventilation prevents gas exchange

  • CO2 is not able to be expelled and is this retained by the body

  • resulting in respiratory acidosis

  • kidneys attempt to compensate by excreting more H

respiratory acidosis

causes

• anything that prevents proper gas exchange

• injury to brain, nerve, or spinal cord that controls respiratory rate

• drugs that affect respiratory rate

  • anesthetics and opiates

• weakness in muscles of respiration

• pneumonia

• obstructive airway disease

respiratory alkalosis

def

• hyperventilation

  • too much CO2 is exhaled

  • resulting in an increase in pH

  • kidneys try to compensate and reabsorb H

respiratory alkalosis

• causes

  • anxiety

  • fever

  • pain

  • high ambient temperature

  • nervous system disease

respiratory compensation

• body will change

  • respiratory rate to alter CO2

  • kidney excretion of H and HCO3 in urine

metabolic acidosis

• increased production of acids or loss of HCO3

• pulmonary compensation

  • hyperventilation

    • get rid of CO2

      • increase pH

metabolic alkalosis

• too much loss of H

• pulmonary compensation

  • hypoventilation

    • retain CO2

      • decrease pH

birds

• air sacs in addition to lungs

• no alveoli

• no muscular diaphragm

• inhalation and exhalation

frogs

• pulmonary cutaneous system

  • can breathe through their skin

• air pouch in bottom of throat

fish

• gills instead of lungs

• countercurrent flow of water and blood in capillaries of gills

Eupnea =

normal, relaxed breathing

Hyperpnea

• increased rate and/or depth

Tachypnea

•  abnormally increased rate 

Polypnea

• increased rate with decreased depth

• Rapid, shallow breathing  panting

• Usually not considered abnormal

Dyspnea

• difficult breathing

Bradypnea

• abnormally slowed breathing

Apnea

• cessation of breathing 

pneumothorax

• wall of thoracic cavity is injured

• air leaks into thoracic cavity

• collapse of lung

pulmonary emphysema

• conditions which destruction of alveolar membranes has occurred

• resulting in smaller area available for gas diffusion

• seen with chronic bronchitis

  • increase the positive pressure with alveoli that is needed for the expiratory phase of the respiratory cycle 

pneumonia

• airway restriction by music and inflammation

• labored breathing

• bacteria and inflammation passageways

• acidotic

• increases RR

pleuritis/pleurisy

• inflammation of the lining of the lungs

• hard to take in breath

• rapid shallow breathing