Chapter 13 Respiratory Sys

– Disorders & Development

Respiratory Disorders: Respiratory Disorders: 1. Chronic Obstructive Pulmonary Disease (COPD)1. Chronic Obstructive Pulmonary Disease (COPD)

Chronic bronchitis & Emphysema

Major causes of death & disability in US

Features

-History of smoking

-Labored breathing (dyspnea)

-Coughing & frequent infections

-Retain carbon dioxide

-Hypoxia & respiratory acidosis

-Ultimately develop respiratory failure

EmphysemaEmphysema Alveoli enlarge as chambers break

Chronic inflammation promotes lung fibrosis

Airways collapse during expiration

Much energy to exhale

Over-inflation leads to a barrel chest

Cyanosis appears late in the disease

Chronic BronchitisChronic Bronchitis Mucosa of respiratory

passages becomes inflamed

Mucus production increases

Pooled mucus impairs ventilation and gas exchange

Risk of lung infection

Pneumonia is common

Hypoxia and cyanosis occur early

Chronic Obstructive Pulmonary Disease (COPD)Chronic Obstructive Pulmonary Disease (COPD)

Figure 13.13

Lung CancerLung Cancer

1/3 of all cancer deaths in the U.S.

Smoking = incidence

Three common types

- Squamous cell carcinoma

- Adenocarcinoma

- Small cell carcinoma

Sudden Infant Death syndrome (SIDS)Sudden Infant Death syndrome (SIDS)

Apparent healthy infant stops breathing and dies during sleep

Possible problem of neural respiratory control center

One third of cases appear to be due to heart rhythm abnormalities

AsthmaAsthma Chronic inflamed

hypersensitive bronchiole passages

Response to irritants with dyspnea, coughing, and wheezing

Developmental AspectsDevelopmental Aspects Fetal lungs filled with fluid

Not inflated til 2 weeks after birth

Surfactant that lowers alveolar surface tension not present until late fetal development; may not be present in premature babies

Developmental AspectsDevelopmental AspectsImportant birth defects

Cystic fibrosis – thick mucus clogs the respiratory system

Cleft palate

Newborns – 40 to 80 rpm

Infants – 30 rpm

Age 5 – 25 rpm

Adults – 12 to 18 rpm

Rate increases with old age

Respiratory Rate Changes Through Life

Aging EffectsAging Effects

Elasticity of lungs

Vital capacity

Blood oxygen levels

Controlling effects of carbon dioxide

Respiratory tract infection