Adrenalectomy in a Golden RetrieverBetty LobanovJan 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

▫ 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)▫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 TestTime 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

guarded-poor• 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

▫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•CBC•Chemistry panel•Abdominal

ultrasound•Thoracic radiographRESULTS: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- Profusehemorrhage 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

▫ 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

▫ Discontinued Hetastarch & Fentanyl CRI▫ Prednisone 5mg PO▫ Omeprazole 20mg PO▫ PT/PTT

• Discharged 9/28/13

Complications

•Addisonian crisis▫Hypoadrenocorticism▫Lack of aldosterone

•Hemorrhage•Fluid & electrolyte imbalances•Pulmonary thromboembolism•Delayed wound healing

Histopathology

◦ NORMAL

ADRENAL MASSDx: Locally extensive cortical adenoma

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

• Hospitalization = $1,219▫ 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

Total: $3,780.68

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 (1999-2005). J Am Vet Med Assoc 2008; 232:77-84

Questions?