Help with objective data

you can include both objective and subjective data to support your nursing diagnosis. let me ask you why you think vital signs would have something to do with a patient's knowledge deficit? the definition of deficient knowledge, the nursing diagnosis, is: "absence or deficiency of cognitive information related to a specific topic." (nursing diagnoses: definitions & classification 2005-2006 published by nanda international, page 112.) the defining characteristics for this particular diagnosis are the following:

• verbalization (the patient has stated) that the lack the knowledge
  
• inaccurate follow-through of the knowledge (they are performing what they were previously taught incorrectly)
  
• inaccurate performance (doing the thing wrong)
  
• inappropriate or exaggerated behaviors (ex: being hysterical, agitated, apathetic or hostile while doing the actions)

vital signs don't belong with this diagnosis as a defining characteristic. in fact, the only assessment data that you have to support this knowledge deficit is your observation of the patient's inaccurate performance.

what you are missing is another nursing diagnosis altogether. you might want to consider ineffective airway clearance. that would account for all the other symptoms you mention and support that nursing diagnosis. you could then include the teaching of deep breathing and coughing with ineffective airway clearance or leave it in it's own nursing diagnosis if the patient has the other factors affecting his cognitive ability to learn to satisfy using deficient knowledge.