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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
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