Surgical Risk


Laryngeal paralysis surgery risk

Q: Dear Dr. Mike - My 13.5 year old golden retriever/irish setter mix has been diagnosed with Laryngeal paralysis. She does not have hyperthyroidism and has a strong heart and is in otherwise pretty good health. The surgeon also found a growth on her vocal chords. The surgeon has recommended surgery, but has warned me of potential complications such as pneumonia due to water/saliva etc. going down into her lungs. My questions are as follows:

1) What is the danger of surgery and general anesthesia for a 13.5 year old dog? Statistically, how many come through fine?

2) Given her general good health, would she be expected to recover fully? Or how long would it take for full recovery?

3) What is the statistical chance of her getting pneumonia from this surgery?

4) What are the dangers associated with removing the growth on the vocal chords?

5) Is there anything else I should consider or know about to help make my decision?

6) What would be your recommendation? Thank you very much for your help!

A: John- Most your questions are difficult to answer directly with the information available to veterinarians. There are few statistics kept on surgical or anesthetic success in veterinary medicine since there are few insured patients and few regulatory agencies collecting data directly from practicing veterinarians.

1) I can not remember losing a geriatric patient due to anesthesia, ever, in 18 years of practice. I have had older patients die during surgery but these have been deaths due to complications of the surgical procedure as far as I could tell. The risk of this depends on the surgery being contemplated. The risks associated with largyngeal surgery generally occur in the post-surgery time period so in this case the surgical time is not that risky.

2)Older dogs recover at approximately the same rate as younger animals except that they are a little more likely to be sensible and take it easy for a few days post-operatively.

3) I searched the databases I have access to and it appears that the rate of unacceptable post-surgical complications runs about 10% but there was a not a breakdown to indicate what percentage of dogs had pneumonia. Complications included post-operative hemorrhage, scarring causing obstruction of the airway, aspiration pneumonia and progression of neurologic signs despite surgical correction. In one study (the smallest) the complication rate was 30% but this was the only one with results even close to this bad.

4)Scarring would seem to be more likely with the removal of a tumor since there is less control over how much tissue is removed and which tissue is removed.

5)Hypothyroidism is a common complication in laryngeal paralysis cases. Even low normal thyroid values should be suspect when laryngeal paralysis is present.

6)If the tumor is already causing respiratory difficulty it seems to me you have little to lose by trying surgery, except the cost. If you can afford to have this surgery done without harming the care of other family members it seems to me that it is worth a try.

Good luck with this.

Mike Richards, DVM

Surgical risk for older dog

Q: Dear Dr Mike, Our 13 yr old German Shepard mixed female went in for her annual shots and during the examination the vet found 3 masses in her mammaries; one involving the gland. The dog is in good health; the only evidence of age seems to be arthritis in her hind quarters this started several months ago. We have been treating it with buffered asprin as needed. Since she was not spayed, the vet recommended that we have the masses removed and spay her at the same time since these tumors are normally hormone related. The vet took a blood to test for both heartworm and for pre-surgery testing. The blood test came back with high levels of alkaline phosphates indicating cushings disease. The vet indicated that cushings disease slows healing, so it would be necessary to put her on medication for several months prior to the surgery. The vet recommended that we take her in to a local animal hospital for more extensive bloodwork and for x-rays of the abdominal & chest areas. The x-rays of the chest area are to determine if the tumors have invaded her lungs. I have two questions; I have heard that surgery on older dogs is extremely risky and this dog has had no prior surgeries, so her sensitivity to anesthetic is unknown. Also, at her advanced age would the tumors significantly cut her life expectancy, since the normal life expectancy in this breed is 15-17 yrs? Of course, the quality & comfort of her remaining years is also important. Thank you, Vickie

A: Vickie- I have never really understood the logic behind thinking that older animals are more susceptible to anesthetic problems. Personally, I would much rather anesthetize a twelve year old dog with no previous history of anesthesia than a six month old one with the same history. Just the fact that the dog lives to be twelve or thirteen years old is a good sign that its body works well and is not likely to have a serious hidden defect that would lead to sensitivity to anesthesia. The veterinarians who claim that older animals are at an increased risk of anesthetic complications believe that as a pet ages it is more likely to accumulate problems such as heart valve insufficiencies, kidney damage or liver damage which make anesthesia a greater risk. I have repeatedly asked veterinarians which patients die most frequently from unexplained anesthetic crises and virtually all of them have lost a patient during a spay procedure, an ear crop or some other pediatric surgical procedure and very few can remember an incidence of anesthetic death in an older pet. Surgical deaths are more common in this age range because the surgeon is less likely to be doing a routine procedure on healthy tissue but I strongly question the assumption that there is an increased risk of anesthetic death in an older patient with normal clinical signs other than a problem such as mammary cancer. Particularly if the better anesthetic agents are used.

It is probably best to take lung X-rays and be sure the tumors haven't metastasized prior to surgery. Canine mammary tumors are benign most of the time but it is still a worthwhile precaution.

Mammary tumors grow unpredictably in size in dogs. Some stay small for long periods of time and other grow so rapidly that it kills the tissue around the tumor and necrotic abscesses form. In most cases, your dog will enjoy a much higher quality of life without the tumors. Since mammary tumors seem to enlarge under the influence of the reproductive hormones it is best to spay a bitch at the time of mammary tumor removal. While there is no sure way of knowing it is very likely that tumor removal could extend her lifespan.

Rises in alkaline phosphatase levels can occur for a number of reasons and Cushing's disease is only one of them. If this is the only abnormality on labwork it probably wouldn't deter me from doing surgery but a more complete workup is not harmful and may be helpful.

Again, age is not a major factor in anesthetic safety. Preanesthetic examination and labwork are likely to uncover any hidden problems that may impact on anesthesia such as kidney disease or diabetes that are more common in older dogs. As long as the exam and tests seem normal there should be no significant increase in risk in anesthetizing an older patient.

Mike Richards, DVM


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...