PSIO 241 CH 13 cont..

anemia

reduction in Hb concentration

polycythemia

higher than normal Hb concentration

carbon monoxide poisoning

• Carbon monoxide (CO) binds with Hb to form carboxyhemoglobin (COHb)

• CO decreases __**functional concentration**__ of Hb; form of acute-onset anemia

• Condition worsens because Hb-O2 dissociation curve **shifts to left**, P50 is decreased, unloading of O2 is hindered

histotoxic hypoxia

**Venous PO2 (oxygen) is elevated** because tissue oxidative processes are inhibited, tissue uses less oxygen.

COPD

Chronic obstructive airway disease

• In all these disorders **expiration is affected more than inspiration resulting in over-inflated lungs**, barrel chest, need accessory muscles for resting expiration.

asthma

characterized by expiratory airflow limitation due to hyperactive bronchi, inflammation, mucous hypersecretion and bronchoconstriction

chronic obstructive bronchitis

an inflammation of the bronchioles characterized by excessive production of mucous

emphysema

characterized by a loss of elastic recoil due to destruction of elastic tissue

restrict pathology

In restrictive conditions, compliance is decreased, lungs are stiff and smaller; decreased inspiration

causes:

* loss of surfactant
* fibrosis
* chest wall diseases
* neuromuscular diseases