EFFECT OF UPPER AIRWAY OBS)'RUCTION ON THE LOWER AIRWAY AND CARDIOVASCULAR SYSTEM JOSEPH
ST.
H.
OCURA,
M.D.
LOUIS, MISSOURI
crease in P0 2 • The combination of modest hypercapnia and a more marked hypoxia in these experiments suggest that the changes occur at the ventilation perfusion ratio, the degree of changes of arterial hypoxia correlate well with the degree of increase in the expiratory laryngeal resistance. The decline of the Observations Between Nose and Pul- P0 2 values was found to correlate most monary System. Patients were studied linearly with the expiratory laryngeal reemploying a standard body plethysmo- sistance. graph, cathode ray oscilloscope, ink writLaryngeal resistance surgically creer, computer and write-out system. An esophageal balloon was also utilized. In- ated by severing both recurrent larynvestigations involving patients with devi- geal nerves resulted in an arterial blood ated septa were studied and their com- gas decrease in P0 2 • Increased laryngeal pliance and resistance assessed. When obstruction was associated with an inthe nose was obstructed, nasal resistance crease in pulmonary resistance. Thereincreased and lung compliance went fore, neuroanatomic changes in larynx down. can influence changes in the airway. During the past twenty years we have been interested in obstructive disease of the upper airway. This interest stemmed from the acknowledgment that little is known of the area. The following is an outline of past studies conducted in our laboratories.
The effect of nasal obstruction on the pulmonary mechanics of the dog was studied. Unilateral nasal obstruction in the dog was compensated; however, when bilateral obstruction was induced, pulmonary airway resistance was persistently increased and there was a compliance change throughout a five-month observation period.
Experiments in Humans with Nasal Packing for Epistaxis. The observation that some patients who had nasal packing tor epistaxis suddenly died, prompted an investigation into the pathogenesis of this phenomenon. Studies revealed arterial blood gas changes in the P0 2 and PC0 2 in such patients. The P0 2 changes were observed when the nose was packed even though the subject was breathing through his mouth. After the nasal packs were removed the P0 2 returned to normal. This suggests a reflex relationship between the nose and the tracheobronchial tree probably mediated through the maxillary nerves. In conclusion tben, complete nasal obstruction can result in increased pulmonary resistance.
The conclusion of these experiments is that nasal obstruction alters the total pulmonary resistance in human and animal experiments. Arterial Gas Changes in Animals with Laryngeal Obstruction. Experiments in dogs revealed that laryngeal obstruction resulted in an elevated PC0 2 and de-
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ST.
H.
OCURA,
M.D.
LOUIS, MISSOURI
crease in P0 2 • The combination of modest hypercapnia and a more marked hypoxia in these experiments suggest that the changes occur at the ventilation perfusion ratio, the degree of changes of arterial hypoxia correlate well with the degree of increase in the expiratory laryngeal resistance. The decline of the Observations Between Nose and Pul- P0 2 values was found to correlate most monary System. Patients were studied linearly with the expiratory laryngeal reemploying a standard body plethysmo- sistance. graph, cathode ray oscilloscope, ink writLaryngeal resistance surgically creer, computer and write-out system. An esophageal balloon was also utilized. In- ated by severing both recurrent larynvestigations involving patients with devi- geal nerves resulted in an arterial blood ated septa were studied and their com- gas decrease in P0 2 • Increased laryngeal pliance and resistance assessed. When obstruction was associated with an inthe nose was obstructed, nasal resistance crease in pulmonary resistance. Thereincreased and lung compliance went fore, neuroanatomic changes in larynx down. can influence changes in the airway. During the past twenty years we have been interested in obstructive disease of the upper airway. This interest stemmed from the acknowledgment that little is known of the area. The following is an outline of past studies conducted in our laboratories.
The effect of nasal obstruction on the pulmonary mechanics of the dog was studied. Unilateral nasal obstruction in the dog was compensated; however, when bilateral obstruction was induced, pulmonary airway resistance was persistently increased and there was a compliance change throughout a five-month observation period.
Experiments in Humans with Nasal Packing for Epistaxis. The observation that some patients who had nasal packing tor epistaxis suddenly died, prompted an investigation into the pathogenesis of this phenomenon. Studies revealed arterial blood gas changes in the P0 2 and PC0 2 in such patients. The P0 2 changes were observed when the nose was packed even though the subject was breathing through his mouth. After the nasal packs were removed the P0 2 returned to normal. This suggests a reflex relationship between the nose and the tracheobronchial tree probably mediated through the maxillary nerves. In conclusion tben, complete nasal obstruction can result in increased pulmonary resistance.
The conclusion of these experiments is that nasal obstruction alters the total pulmonary resistance in human and animal experiments. Arterial Gas Changes in Animals with Laryngeal Obstruction. Experiments in dogs revealed that laryngeal obstruction resulted in an elevated PC0 2 and de-
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