decreased pulmonary perfusion associated with obstruction of pulmonary arterial blood flow by the embolus and vasoconstriction resulting from the local release of vasoactive substances (e.g. serotonin, endothelin, some prostaglandins);
decreased bronchial airflow associated with bronchoconstriction resulting from:
the local release of substances such as serotonin and some prostaglandins
a compensatory response to an increase in the amount of dead space in the underperfused lung area (the compensatory bronchoconstriction also affects airways in perfused lung areas);
loss of effective lung surface associated with atelectasis if it occurs.
The client will experience adequate O2/CO2 exchange as evidenced by:
usual mental status
unlabored respirations at 12 - 20/minute
oximetry results within normal range
blood gases within normal range.
Nursing Actions and Selected Purposes/Rationales
Assess for and report signs and symptoms of impaired gas exchange:
significant decrease in oximetry results
decreased PaO2 and/or increased PaCO2
central cyanosis (a late sign).
Implement measures to improve gas exchange:
maintain client on bed rest to reduce oxygen demands during acute respiratory distress; increase activity gradually as allowed and tolerated
maintain oxygen therapy as ordered
perform actions to improve breathing pattern (see Diagnosis 1, action b)
discourage smoking (the carbon monoxide in smoke decreases oxygen availability and the nicotine can cause vasoconstriction and further reduce pulmonary blood flow)
perform actions to improve pulmonary blood flow:
administer anticoagulants (e.g. continuous intravenous heparin, low-molecular-weight heparin, warfarin) as ordered
prepare client for the following if planned:
injection of a thrombolytic agent (e.g. streptokinase, alteplase [tPA])
Consult appropriate health care provider (e.g. respiratory therapist, physician) if signs and symptoms of impaired gas exchange persist or worsen.