Pheochromocytomas and other Adrenal tumors


Adrenal tumor, death after surgery, risk factors

Question: Hi..I am a recent subscriber and in addition to a few questions, I want to thank you for helping me through a very tough time. So much of the information on your site has helped me come to terms with what happened to my dog Zack. I know that my questions are after the fact, however I desperately need the prespective from someone who can look at the facts in an unbiased manner.

Zack who would have been 13 in October, was diagnosed with an adrenal tumor in May ( ultrasound.) We started seeing symptoms in January, however understandably it was misdiagnosed as diabetes and some other things and we spent valuable time treating them. By May he was having trouble making it back from walks but other than the frequent urinating and drinking he had no other problems that we know of. Then over a weekend he went blind and deaf.

We made the decision to operate on the tumor and the surgeon at the emergency clinic reported that he had gotten most of the tumor except some attached to the renal artery. They had to ventilate during surgery, but he was stable. That was at about 5:30 pm and at 1:30am he was making peculiar vocalizations (they used isoflourine during surgery but he should have been awake from it by then?) and they gave him pain meds (Torbalgesicsp??) this happened again at 3:30 and then at 6:30am. At 6:30 they also gave him a needleprick of numorphan. By 7:00am he had stopped breathing. They said it was a complete shock and out of the blue. They did think that there was blood in the abdomen.

These are my questions and I know from what I have read you will be honest with me:

The emergency clinic said that it would best if we weren't with him after surgery b/c he would need to be calm and not excited so we were not with him when he died like we promised him we would be. We rarely left his side over his almost 13 years. Would Zack have known we weren't there or would the medications have him sedated enough not to know any different? And do you think if we'd been there we could have calmed him down and he wouldn't have volcalized, causing them to give the numorphan? If I am ever responsible for another pet I need to know how to handle things differently in the future...

Should the numorphan been administered given that they had to ventilate during surgery and he had a rough time recovering from the sedative given for the ultrasound? We did tell them all about that as well as the tough time during walks.

I have read on your site that adrenal tumors are risky however didn't see any information about what particularly increases the risks.

Thank you in advance for your response. All of this has happened so fast. For so long my husband and I and our two daughters have had an intense relationship with Zack and to have it all end so suddenly and so traumatically we feel that we have failed our poor dog so badly by allowing the misdiagnosis (I finally diagnosed it myself with info from your site) and then the surgery possibly when his heart was too weak, and then by not being there with him when he needed us the most.

Zack was a mixed breed, possibly german shepard/ collie, 65 pounds and the liver looked good on the ultrasound, as well as the vet said that kidneys were also good if that helps at all.

Thank you so much, Cheryl

Answer: Cheryl-

Adrenal gland tumors tend to fall into one of three classes, adrenal gland carcinomas, adrenal gland adenomas and pheochromocytomas. The risk associated with surgery varies a little, depending on which tumor type is present.

Adrenal gland carcinomas and adenomas tend to produce hyperadrenocorticism, or Cushing's disease. This condition causes changes in the blood glucose levels, the electrolyte levels, the blood pressure and it increases the tendency for blood to clot, leading to an increase in pulmonary embolisms. In addition, if only one adrenal gland is affected, the increased production of cortisols from this gland tends to make the other adrenal gland atrophy, so that it is not functioning well when the cancerous gland is removed. These factors all increase the risk of surgery. Urinary tract infections are also extremely common in patients with Cushing's disease and these can lead to postsurgical complications if the stress of the surgery further suppresses the immune system, allowing the infections to get out of hand. Adrenal gland carcinomas frequently invade the surrounding blood vessels and organs and may affect both adrenal glands, which significantly increases the surgical risks. Adrenal gland ademomas are more likely to affect one gland and the postsurgical survival time is better for this type of tumor. The greatest postsurgical risks for these tumors are sudden drops in plasma cortisol levels and pulmonary embolism. Other possible surgical complications are hemorrhage during surgery and postoperatively, electrolyte imbalances, pancreatitis from blood clots or manipulation of the pancreas during surgery and complications from undetected or uncontrolled urinary tract infections that become severe due to the stress of the surgery.

Pheochromocytomas also cause disturbances in electrolyte levels, increases in blood pressure (sometimes life threatening with or without surgery) and increased tendency for blood clotting to occur. These tumors will release substances (catecholamines) when manipulated that make all of these problems significantly worse, making them an even greater surgical risk. The major complications with these tumors are severe spikes in blood pressure and pulmonary embolisms. The other complications include pancreatitis, hemorrhage and electrolye imbalances.

While surgeons know about the potential for complications, it is hard to prevent them, even with great care. For this reason, the death rates in the surgical and immediate postsurgical period for these types of tumors are very high. Patients who live through the surgery and immediate postoperative period can have good long term prognoses, though. So even with the risk, these surgeries may be the best option for many patients, although medical treatment may be an option for the adrenal gland adenomas and adenocarcinomas.

Numorphan (Rx) is the trade name for oxymorphone. Torbugesic SA (Rx) is the trade name for butorphanol. These are both opioid medications. Opioids can be divided up into classes based on whether they stimulate opioid receptors (agonists) or inhibit them (antagonists). There are several receptors for opioids and different drugs may be pure agonists (only stimulate receptors), pure antagonists (only block receptors) or mixed agonists (mixed antagonists) -- block some receptors and stimulate others. Oxymorphone is an agonist and butorphanol is a mixed agonist. In general, the pure agonists are better pain relievers but as odd as it sounds, both agonists and antagonists have pain relieving effects. The reason that I went into this discussion is that butorphanol, because it has some antagonistic properties, can interfere with the action of oxymorphone by blocking access to receptors. So there is some chance that even though oxymorphone was administered, it may not have had as much effect as if it was administered when butorphanol had not been used. This could be viewed as a good thing, if Zack was sensitive to its effects, or a bad thing, if he needed the pain relieving effect of the oxymorphone. In general, pain relief is beneficial enough that it should be attempted, even when there are complications with anesthesia during surgeries with significant potential for post-operative pain. This is somewhat of a judgment call, but pain relief helps more often than it hurts and so I would favor their use in most circumstances. If an opioid was used in sedation for the ultrasound examination and Zack was sensitive to its effect, that would influence the decision making on this issue. However, opioids are rarely used as a sole agent and the sedatives they are used with are often viewed as the culprit when dogs react adversely to the sedation with combinations of sedatives or tranquilizers and opioid medications.

The hardest question to answer is whether it would have been better if you could have been with Zack. My personal opinion on this is that almost all patients are better off if they can have comfort and support from their families. I do believe that it is most likely that Zack would have known you were there. It is less clear if it would have been helpful. I think for most pets it is and that it may have made him less likely to whine, cry or make other vocalizations. A few dogs and cats seem to really want to be left alone, but they are the exception, in my opinion. If the vocalization was due to confusion from being in unfamiliar surroundings having a family member probably would have helped with that. It wouldn't have made me want to stop or avoid pain relief medications, though. It is almost certain that pain was present after a surgery as extensive as removal of an adrenal gland tumor.

However, there is another side to this. In some cases family members seriously interfere with the delivery of medical care, even though their intentions are good. In some instances, this interference becomes life threatening, either to the patient they are concerned about, or to other patients in the hospital. This can happen when owners ask questions during procedures in which the veterinarian or technician really need to concentrate, when owners object to necessary restraint or to necessary procedures and delay care and when owners become verbally or physically abusive of the staff. I have had owners physically threaten me and two owners actually resorted to punching me or hitting me with handy objects when I was doing the best that I could to save their pets. This year, I had a small bird owner grab my arm, just as I was clipping her bird's toenail and this resulted in total removal of the nail -- which became an instant life threatening situation. These are really tense emotional moments and superimposing them on routine medical care can be extremely difficult. So veterinary hospitals have to weigh the interference with delivery of care against the potential benefits for the pet. Many veterinarians and veterinary staff members become convinced that the risk of a family member interfering with care exceeds the potential benefits. I really do find this understandable. It isn't how we practice, most of the time, but I do understand what they are thinking. In addition to this problem, one of my associates really truly believed that pets were upset by visits from their owners and by the presence of their owners post-surgically, because the owners left at some point and that was stressful. We had long discussions about this at times and were never able to reach an agreement, except to recognize that there probably are some pets who prefer to be left alone and some that prefer to be with their families. I just think the majority are in the latter category.

We attempt to reach a compromise by telling clients they can stay with their pets only if they do not interfere with the care of their pet or any other pet in our hospital (such as by demanding attention for their pet when another pet has immediate needs that we believe are more pressing) and that they must agree to leave immediately, if asked. We almost never have to ask, because most pet owners are very good. But we have had to make at least one pet owner leave this year in order to try to efficiently work on their pet in an effort to save its life. This person claims they will not return, even though we were successful in our efforts. We're not too concerned about the loss of the client but we do wonder how they are presenting their side of the story to people in our community.

These are the sort of issues that vets are struggling with when attempting to set policies about letting owners stay with their pets. While I favor letting families stay with pets during recovery if they wish to, I am not absolutely certain it is best in all situations for the pet and I know that it makes things a little harder for my staff.

I am hopeful that this information is helpful. I don't think you should feel guilty about Zack's care. After all, you took on the responsibility of seeking information to help him and succeeded in finding an answer through persistence. While the outcome wasn't good it wasn't because you didn't try to do the right things. That is all that we can ask of our families and even our health care workers, because no one can guarantee a good outcome. All we can do is to try to make it happen to the best of our ability and it really seems to me that you did that.

Mike Richards, DVM 8/21/2001


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...