Adrenalectomy in a Golden
Retriever
Betty Lobanov
Jan 29th 2014
Signalment & History
• 10 year old female
spayed Golden Retriever
•Presented to CUHA Soft
Tissue Surgery service
for adrenalectomy
• Presenting complaints
to rDVM 2 months prior
•Polyphagia
•Polyuria
•Alopecia
•Muscle atrophy
Problem List
• Alopecia
▫ Primary dermatologic, Endocrine, Immune mediated
• Polyphagia
▫ Endocrine
• Polyuria
▫ Endocrine, Renal disease, Hypercalcemia, Diuresis,
Pyelonephritis, Psychogenic
• Muscle atrophy
▫ Degenerative, Endocrine, Nutritional, Immune
mediated, Neurologic, Orthopedic
Diagnostics
• Senior wellness exam April 2013
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CBC: mild lymphopenia
Chem: ↑cholesterol, ↑triglycerides
T4: WNL
Urinalysis: 2+ proteinuria
USG 1.016
• USG & urine protein re-checks recommended
▫ 3+ proteinuria, USG 1.036
• Proteinuria still persisted  recommended urine
protein:creatinine (UPC), blood pressure, urine
culture/sensitivity
▫ UPC 1.3 (normal < 0.5)
▫ Culture/Sensitivity: No growth
▫ Monitor & re-check in 4 months
Diagnostics
• Re-check August 2013
▫ CBC: lymphopenia, eosinopenia
▫ Chem: ↑cholesterol, ↑triglycerides
▫ Urine culture/sensitivity: E.coli organisms
 Amoxicillin 400mg
 Re-check 5-7 days after termination of therapy  no
growth
Problem List
• Alopecia
▫ Primary dermatologic, Endocrine, Immune
mediated
• Polyphagia
▫ Endocrine
• Polyuria
▫ Endocrine, Renal disease, Hypercalcemia, Diuresis,
Pyelonephritis, Psychogenic
• Muscle atrophy
▫ Degenerative, Endocrine, Nutritional, Immune
mediated, Neurologic, Orthopedic
But wait, there’s more…
• Dermatologic punch biopsy 7/12/13  Calcinosis
cutis
• Abdominal ultrasound 7/30/13  adrenal mass
• ACTH stimulation test
▫ Screening test
▫ Confirmatory test
▫ Evaluates ability of adrenal gland to secrete cortisol
after maximal stimulation
▫ Protocol
 serum cortisol collected for baseline and 1 hour after
administering 0.25 mg synthetic ACTH IM
 serum cortisol collected for baseline and 2 hours after
administering 2.2 U/kg ACTH gel IM
Hyperadrenocorticism [HAC]
Time vs. Cortisol
• Patient’s ACTH stim consistent with Cushing’s
(hyperadrenocorticism)
▫ Pre 5.0ug/dL (ref 1.8-4)
▫ Post > 50ug/dL (ref 6-16)
• Low Dose Dexamethasone Suppression Test (LDDS)
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Differentiating test
Pre 3.8ug/dL
Post 4hr: 1.5ug/dL (healthy dog < 1ug/dL)
Post 8hr: 2.3ug/dL
Protocol
 Baseline blood sample for cortisol
 Inject 0.01 mg/kg dexamethasone obtain blood sample at 4 &
8hr
LDDS Test
Time vs. Cortisol
• Medical management: Trilostane
▫ PDH, ADH
▫ Competitive inhibition of steroid synthesis
 3β-hydroxysteroid dehydrogenase
▫ Daily doses needed
▫ Cats, Dogs, Birds
• Re-check cortisol levels post initiating Trilostane
▫ ACTH stim
 Pre 1.9ug/dL (ref 1.8-4)
 Post 2.4ug/dL (ref 6-16)
▫ Trilostane decreased from 60mg to 30mg
Hyperadrenocorticism (Cushing’s)
• 3 types –treated differently and different prognosis
• Pituitary dependent hyperadrenocorticism (PDH)
▫ 85%-90%; overproduction ACTH
▫ Can live normal lives for many years with medical management
(controlling adrenal gland)
▫ 15% neurological signs
 Macroadenomas > 1cm in diameter
 Microadenomas < 1cm in diameter
• Adrenal dependent hyperadrencocorticism (ADH)
▫ Functional tumor on the adrenal cortex
▫ Adenoma or carcinoma
▫ Benign  surgical removal, curative
▫ Malignant  surgical removal may help but prognosis guardedpoor
• Iatrogenic
▫ Excessive administration of an oral or injectable steroid
Hyperadrenocorticism (Cushing’s)
Adrenal Architecture & Products
Back to our visit
• 9/24/13 CUHA Soft Tissue Surgery
• Physical exam
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T: 101.8°F P: 108bpm R: 32bpm
23.5kg
BAR
Bilateral alopecia around the elbows
Hindlimb muscle atrophy
Healing sebaceous cyst on right hindlimb
Pre-op Diagnostics
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CBC
Chemistry panel
Abdominal ultrasound
Thoracic radiograph
RESULTS:
CBC: no significant findings
Chem: ↑cholesterol 557mg/dL (ref 138-332mg/dL)
↑triglycerides 314mg/dL (ref 22-125mg/dL)
Abdominal U/S: caudal pole of left adrenal gland
hyperechoic mass; right adrenal gland normal
Thoracic radiographs: no evidence of metastases
Surgical Approaches
• Ventral midline
▫ Dorsal recumbency, surgically prepped
▫ Xiphoid-pubis incision
Surgical Approaches
• Paralumbar
▫ Lateral recumbency, surgically prepped
▫ Lateral vertebral process-within 3-4cm of ventral
midline incision (caudal to 13th rib)
Surgical Approaches
• Laparoscopic
▫ Lateral/near-lateral with affected gland up, surgically
prepped
▫ Endoscopic tower directly opposite surgeon facing
patient’s back
▫ 3 or 4 port technique; Instrument ports are placed in a
triangulating pattern around the location of the
adrenal gland
Approach
Pros
Cons
Ventral midline
-Standard approach
-Enhanced visualization
for
exploratory/metastatic
evaluation
-Exposure of both
adrenal glands
-Dehiscence
-Exposure & dissection
may be difficult in large
dogs
Paralumbar
-Better access to adrenal
gland
-Minimal dissection and
damage to pancreas
-Limited metastatic
evaluation
-Dehiscence
Laparoscopic
-Minimally invasive
-Decreased pain
-Less risk of dehiscence,
wound infection
-Shorter hospitalization
-Ability to address
complications
compromised
- Profuse
hemorrhage possible
Exposure via Paralumbar
9/25/13 Surgery Day
• Exploratory laparotomy & Left adrenalectomy
▫ Xiphoid-pubis incision
▫ Abdominal exploration: unremarkable
▫ Mass identified & dissected
 Right angle forceps, tenotomy scissors,
bipolar electrocautery (hemostasis)
▫ Phrenicoabdominal vein ligated with
hemoclips
▫ 2 layer closure
▫ Skin staples & Tegaderm patch
• Intra-op Dexamethasone IV
Post-operative Care
• 9/25/13
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Dexamethasone IV
Plasmalyte fluids IV
Fentanyl CRI
Fragmin SQ
• 9/26/13
▫ Plasmalyte fluids IV
▫ Fentanyl patch
▫ ACTH stim
 Pre 0.25ug/dL (ref 1.8-4)
 Post 3.74ug/dL (ref 6-16)
▫ Discontinued Fragmin
• 9/27/13
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Discontinued Hetastarch & Fentanyl CRI
Prednisone 5mg PO
Omeprazole 20mg PO
PT/PTT
• Discharged 9/28/13
Complications
• Addisonian crisis
▫ Hypoadrenocorticism
▫ Lack of aldosterone
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Hemorrhage
Fluid & electrolyte imbalances
Pulmonary thromboembolism
Delayed wound healing
Histopathology
◦
ADRENAL
MASS
Dx: Locally
extensive
cortical
adenoma
NORMAL
Adrenal Neoplasia
• Adrenocortical
▫ Adrenal carcinoma
▫ Adrenal adenoma
• Pheochromocytoma: catecholamine secreting
tumors arising from medullary tissue
• Clinical signs due to nonfunctional tumors are
caused by local invasion of the tumor into
surrounding tissue, distant metastases, or both
• Functional tumors secrete excessive amounts of
cortisol, which inhibits pituitary ACTH secretion
and causes atrophy of the contralateral adrenal
gland
Adrenal Neoplasia
• Adrenocortical adenomas and carcinomas appear to
occur with equal frequency
• Usually unilateral
• Complications
▫ Adrenal insufficiency
▫ Pulmonary thromboembolism
▫ Pancreatitis
 Post op 2.5-11% (Schwartz 2008)
 Increase in manipulation due to invasive tumor
▫ Recurrence
 Clinical signs related to HAC within 3 years ~ 33%
(Axlund 2003)
Cost
• Visit + Specialty exam = $123
• Diagnostics = $579
• Surgery & Anesthesia = $1,113
▫ Adrenalectomy = $462
▫ Isoflurane = $206
Total: $3,780.68
• Hospitalization = $1,219
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ICU Maintenance = $165 + $165
Cosynotropin $62
ACTH stim = $29.48
PT/PTT = $80
Fragmin = $110 + $216
BP monitoring = 3 x $32 = $96
Gaslyte monitoring = $64 + $96 + $64
PCV/TP = 2 x $36
Patient follow-up
• 10/8/13 re-check at CUHA Soft Tissue Surgery
Service
▫ Ravenous appetite diminished
▫ Discontinued Omeprazole and Fentanyl patch
▫ Taking Prednisone
• 10/23/13
▫ rDVM call: doing well clinically, taking Prednisone
EOD
▫ ACTH stim
 Pre 3.4ug/dL (ref 1.8-4)
 Post 14.2ug/dL (ref 6-16)
Thank you to my advisors:
Dr. Harvey
Dr. Jay
Resources
• Axlund TW, Behrend EN: Surgical Treatment of Canine
Hyperadrenocorticism, Vol. 25, No. 5, May 2003
• Feldman EC, Nelson RW: Hyperadrenocorticism (Cushing’s syndrome), in
Feldman BF, Nelson RW (eds): Canine and Feline Endocrinology and
Reproduction, ed 2. Philadelphia, WB Saunders, 1996, pp 187-265
• Fossum, Theresa. Small Animal Surgery, 3rd edition. St.Louis: Mosby Inc.,
2007
• http://www.vsso.org/Adrenal_Cortical_Tumor.html
• Massari F, Nicoli S, et al. Adrenalectomy in dogs with adrenal gland
tumors: 52 cases (2002-2008). J Am Vet Med Assoc 2011; 239:216-221
• Pelaez MJ, Bouvy BM, Dupre GP: Laparoscopic adrenalectomy for
treatment of unilateral adrenocortical carcinomas: Techniques,
complications and results in seven dogs. Vet Surg 2008;37:444-453
• Schwartz P, Kovak JR, Koprowski A, et al. Evaluation of prognostic factors
in the surgical treatment of adrenal gland tumors in dogs: 41 cases (19992005). J Am Vet Med Assoc 2008; 232:77-84
Questions?