Physical Examination: Pulmonary

CO2 Transport CO 2 is carried to the lungs on the hemoglobin, after the oxygen has left to enter the tissues. The carbon dioxide reacts with water in the RBC to form carbonic acid, which then breaks apart into a hydrogen ion (which lowers blood pH) and a bicarbonate ion (which raises blood pH). Here is the carbonic anhydrase reaction: CO 2 + H 2 O  H 2 CO 3  H + + HCO 3 - This reaction is reversible, and would go mainly to the right in the tissues and to the left in the lungs. CO2 is transported in the blood predominately in the form of bicarbonate. The number of H + ions in the blood depends partly on the amount of CO 2 in the blood. The more CO2 in the blood, the more H+ in the blood, which makes the blood acidic. If the blood is too acidic, more bicarbonate ions are reabsorbed by the kidneys to raise the pH. If the blood is too alkaline, bicarbonate ions are excreted by the kidneys. 2

Lung Exam Percussion Auscultation Spirometry

Percussion Extend the middle finger of one hand and place the distal interphalangeal joint firmly against the patient's chest. With the end (not the pad) of the opposite middle finger, use a quick flick of the wrist to strike first finger in the middle of the intermediate phalanx. Categorize what you hear as normal, dull, or hyperresonant.

Percussion and Auscultation Sites Posterior Anterior At each spot, say 99 Then at each spot say “E” Then at each spot say 123

Percussion Notes and Their Meaning Flat or Dull: – Pleural Effusion or Lobar Pneumonia Normal: – Healthy Lung or Bronchitis Hyperresonant: – Emphysema or Pneumothorax –

Normal Lung Sounds upon auscultation m m

Rales m m

Rhonchi These are low pitched, snore-like sounds. They are caused by airway secretions and airway narrowing. They usually clear after coughing. ogy_ls_rhonchi.html ogy_ls_rhonchi.html

Wheezes m m

Measurement Value (Male/Female) CalculationDescription Total lung capacity (TLC) = 6.0 / 4.7 L IRV + Vt + ERV + RV The volume of air contained in the lung at the end of maximal inspiration. Vital capacity (VC) = 4.6 / 3.6 L IRV + Vt + ERV The amount of air that can be forced out of the lungs after a maximal inspiration. Forced vital capacity (FVC) = 4.8 / 3.7 L measured The amount of air that can be maximally forced out of the lungs after a maximal inspiration. Emphasis on speed. Tidal volume (Vt) = 500 / 390 mL measured The amount of air breathed in or out during normal respiration. Residual volume (RV) = 1.2 / 0.93 L measured The amount of air left in the lungs after a maximal exhalation. Expiratory reserve volume (ERV) = 1.2 / 0.93 L measured The amount of additional air that can be pushed out after the end expiratory level of normal breathing. Inspiratory reserve volume (IRV) = 3.0 / 2.3 L measured IRV=VC-(TV+ERV) The additional air that can be inhaled after a normal tidal breath in. Functional residual capacity (FRC) = 2.4 / 1.9 L ERV + RV The amount of air left in the lungs after a tidal breath out. Inspiratory capacity (IC) = 3.5 / 2.7 L measured Vt + IRV The maximal volume that can be inspired following a normal expiration.