Adrenalectomy in Dogs

Adrenalectomy refers to the surgical removal of an adrenal gland, located just in front of the kidney. This procedure is challenging for several reasons and usually only undertaken in a specialist setting by expert surgeons. 

Indications for adrenalectomy include the presence of a tumor. The surgery is high-risk due to difficulty accessing the tumor and the high percentage of cases that throw fatal blood clots in the 24 hours post-surgery. However, those dogs that do survive often have a reasonable long term outlook.

Adrenalectomy requires a full general anesthetic at a facility with the capability to provide rigorous monitoring of blood pressure, blood gases, ECG, and other vital parameters during anesthesia, plus an intensive care facility for the postoperative period. 

Depending on the type of adrenal tumor, the dog may receive medical therapy for two weeks prior to surgery in order to reduce the risk of complications such as throwing a life-threatening blood clot and to control high blood pressure. 

On the day of surgery, the dog should be fasting, and a premed injection is given which includes painkillers. After the dog is anesthetized, the surgeon usually makes on incision in the midline of the dog's belly, although an alternative technique involving an incision high on the right flank is preferred by some specialist when the right adrenal gland is to be removed. 

The surgeon uses retractors to hold the gut and liver aside, in order to gain access to the adrenal gland deep within the abdomen. The blood supply to the gland is tied off and the gland itself dissected away. 

The surgeon closes the laparotomy site and the patient is transferred to intensive care for close monitoring for 24 hours. 

The act of removing the adrenal gland is an efficacious for getting rid of tumors in this location. The ultimate success depends on whether or not the patient survives to leave the hospital, how invasive the tumor was, and if malignant spread has already taken place or not. 

The complication rate is high (again depending on the type of tumor) with blood clots to the lungs being a major source of death peri and post-operatively. Other complications include pancreatitis, kidney failure, pneumonia, and heart rhythm irregularities. 

If surgery is not an option then the clinician can try to control the clinical signs by the use of medication, but this is only palliative and rarely satisfactory.

The patient is at greatest risk during the operation itself and in the 24 hours post surgery. This is because rapid changes in hormone levels, plus the tendency for blood clots to form, can cause catastrophic, potentially fatal, problems that are difficult to control. 

As a rule of thumb, those that cope with this vital time and are able to go home, often do well provided that their cancer was no well advanced prior to surgery. It is essential to observe the regular guidelines during the recovery period, such as preventing the dog from licking the wound, rest, and avoiding stress. 

Medication started prior to surgery is gradually reduced and stopped, as indicated by regular blood pressure monitoring.

Skin sutures are usually removed at the 10 - 14 day point. 

The dog requires an extensive work up prior to adrenalectomy which includes screening blood tests, specific diagnostic blood tests, radiographs and ultrasound. These alone will run into many hundreds of dollars. 

The surgical procedure and the intensive care needed in the postoperative period are costly, and an owner should expect to pay thousands of dollars or more. 

Adrenalectomy is not a procedure to be taken on lightly. Whilst the procedure may be the dog's best option for recovery, the complication rate is high. It is therefore essential that each dog is thoroughly screened prior to going ahead, in order to determine that the cancer is not already far advanced. This would mean that the risks are unacceptable in view of the limited extra time the dog would gain should surgery go well. 

It is not thought that environmental factors play a part in the development of adrenal gland tumors, thus it is difficult for the conscientious owner who wishes to reduce their pet's risk factors to do anything constructive. 

Adrenal tumors seem to be more prevalent in larger dogs than small; and there is an increased occurrence in female dogs over male. But other than that, whether or not a dog develops an adrenal tumor is largely a matter of fate.