I am at a disadvantage not knowing the exact type and location of the tumor that was removed. So unfortunately, I can't say whether that contributed at all to his passing and will have to limit my answer to the treatment Duffy received for the aspiration pneumonia.
In severe cases when the patient is exhibiting significant respiratory distress, oxygen therapy is often necessary. The use of an oxygen cage is generally the least stressful method of delivering oxygen therapy, but as these are quite expensive, not all private practices are equipped with them. Nasal insufflation (placing a tube into the nostrils) is the next best thing. If the cat is not in significant respiratory distress, then oxygen therapy is usually not needed.
Cats with pneumonia will very commonly go off food because they are more concerned with breathing, than eating or drinking. As a result, intravenous fluids are usually recommended to guard against dehydration. Subcutaneous fluids(fluids given just beneath the skin) may be substituted if dehydration is minimal. Force feeding is often needed but this needs to be done several times a day to keep up with the cat's metabolic requirements. Placement of a feeding tube would be ideal and less stressful for the cat, but was not practical in Duffy's situation because he simply could not have withstood another anesthetic procedure given the state of his lungs.
The use of antibiotics is essential in cases of aspiration pneumonia. Ideally, material is collected from the airway for submission for culture and sensitivity to determine what organisms are present and what is the best medication to use. Barring this, a combination of broad spectrum antibiotics such as amoxicillin with gentamicin, amikacin or Baytril, is usually what is required. The use of steroids is controversial- there is inflammation within the airways and the steroids will help alleviate that. In fact, steroids are commonly used in human patients with pneumonia. However, they also suppress the immune system and could potentially make the pneumonia worse. Unfortunately, there is not a good consensus in veterinary medicine as to whether steroids should or should not be used in these cases.
In cats with aspiration pneumonia, bronchodilators such as theophylline or terbutaline often help to open up the airways and aid breathing. Nebulization to loosen up consolidated areas of lung tissue is an important part of therapy in cases that are slow to resolve. Following nebulization, coupage (cupped hands "pounded" against the chest wall), is used to further loosen up secretions and encourage coughing to expel the material. Diuretics are not recommended for cases of pneumonia.
Again, I don't know that I can say that what was done was inappropriate or that the care Duffy received was a contributing factor in his death. The tumor may have played a part in weakening him and making him less responsive to the therapy that was offered, or it could be that sending him home too early proved too much of a stress on his system. As uncomfortable as it may be for you, I recommend that you request a sit down meeting with the veterinarians that were involved in Duffy's care. Approaching them in a non-confrontational manner and asking them to guide you step by step through the disease process and treatment. You may find that they were doing things that you weren't aware of (sometimes things go unmentioned or are assumed). It may be that they were not as upfront with you about how guarded his condition was, or that they felt that they had conveyed that to you but there was a miscommunication somewhere along the line. If they offered him the best quality of care they were capable of, they should have no reservations about discussing things with you and helping you to understand where things went wrong. I'm under no illusions that if they had slipped up somewhere down the line that they would necessarily admit to that- though it certainly would be refreshing. But perhaps learning more about what went on during Duffy's stay will enable you to get a clearer picture of illness and what was done to help him. It may be a good idea to allow yourself more time to grieve before you approach them about a meeting. This may allow you to focus your questions and objectives more clearly so that you are able to gather the information you're seeking.
Unfortunately in a situation like this, sometimes there are more questions than answers. I truly hope that you are able to bring some resolution to this and allow yourself to celebrate the 10 wonderful years you shared with your boy.
Please let me know if I can help you further.
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