Adrenalectomy for the treatment of hypotension in a cat with phaeochromocytoma associated with caudal vena cava syndrome.

An 11-year-old spayed female, Persian cat was referred to the Jeonbuk Animal Medical Center for evaluation of a 2-month history of lethargy and anorexia. Physical examination revealed tachycardia and hypotension. Abdominal imaging via sonography and CT identified a right adrenal gland mass causing severe deviation and compression of the caudal vena cava. After stabilising the blood pressure and heart rate through positive inotropes and fluid therapy, right adrenalectomy was performed. Surgery confirmed the adrenal gland mass was severely compressing the caudal vena cava. Histopathological examination revealed that the mass was a pheochromocytoma. After adrenalectomy, blood pressure and heart rate stabilised and remained unaffected 8 months postsurgery. This report describes a rare case of an adrenal pheochromocytoma leading to caudal vena cava compression in a cat presenting with hypotension.

Ectopic adrenal tissue in a cat that underwent an ovariohysterectomy.

OBJECTIVE: To describe the use of ultrasound and adrenal function testing to confirm that excised periovarian tissue is normal ectopic adrenal tissue (EAT). ANIMAL: A 6-month-old female domestic shorthair cat. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: The cat underwent an ovariohysterectomy procedure, during which abnormal tissue was discovered adjacent to both ovaries. The tissue was removed during the ovariohysterectomy and submitted for histopathology, which was consistent with adrenal gland tissue, initially raising concern for an inadvertent adrenalectomy. Abdominal ultrasound and an adrenal function test were performed that confirmed normal adrenal structure and function; thus, the removed structure was diagnosed as EAT. TREATMENT AND OUTCOME: The patient continued to recover from the procedure uneventfully at home. CLINICAL RELEVANCE: Parovarian nodules are an uncommon finding but when observed and biopsied, may be mistaken for physiologic adrenal tissue on the basis of histopathologic features alone without awareness of their existence and clinical context. The use of abdominal ultrasound and ACTH stimulation test offers an affirmative method of differentiating adrenal gland tissue from EAT.

Adrenal tumors treated by adrenalectomy following spontaneous rupture carry an overall favorable prognosis: retrospective evaluation of outcomes in 59 dogs and 3 cats (2000-2021).

OBJECTIVE: To conduct a retrospective multi-institutional study reporting short- and long-term outcomes of adrenalectomy in patients presenting with acute hemorrhage secondary to spontaneous adrenal rupture. ANIMALS: 59 dogs and 3 cats. METHODS: Medical records of dogs and cats undergoing adrenalectomy between 2000 and 2021 for ruptured adrenal masses were reviewed. Data collected included clinical presentation, preoperative diagnostics, surgical report, anesthesia and hospitalization findings, histopathology, adjuvant treatments, and long-term outcome (recurrence, metastasis, and survival). RESULTS: Median time from hospital admission to surgery was 3 days, with 34% of surgeries being performed emergently (within 1 day of presentation). Need for intraoperative blood transfusion was significantly associated with emergent surgery and presence of active intraoperative hemorrhage. The short-term (≤ 14 days) complication and mortality rates were 42% and 21%, respectively. Negative prognostic factors for short-term survival included emergent surgery, intraoperative hypotension, and performing additional surgical procedures. Diagnoses included adrenocortical neoplasia (malignant [41%], benign [12%], and undetermined [5%]), pheochromocytoma (38%), a single case of adrenal fibrosis and hemorrhage (2%), and a single case of hemangiosarcoma (2%). Local recurrence and metastasis of adrenocortical carcinoma were confirmed in 1 and 3 cases, respectively. Overall median survival time was 574 days and 900 days when short-term mortality was censored. No significant relationship was found between histopathological diagnosis and survival. CLINICAL RELEVANCE: Adrenalectomy for ruptured adrenal gland masses was associated with similar short- and long-term outcomes as compared with previously reported nonruptured cases. If hemodynamic stability can be achieved, delaying surgery and limiting additional procedures appear indicated to optimize short-term survival.

Laparoscopic adrenalectomy for resection of unilateral noninvasive adrenal masses in dogs is associated with excellent outcomes in experienced centers.

OBJECTIVE: To report the short- and long-term outcomes of laparoscopic adrenalectomy (LA) for resection of unilateral adrenal masses and to document risk factors for conversion and peri- and postoperative morbidity. ANIMALS: 255 client-owned dogs. METHODS: Dogs were included if LA was attempted for resection of a unilateral adrenal mass. Medical records were evaluated and relevant data were reported, including complications, conversion, perioperative death, and long-term outcomes. Signalment, clinicopathological data, and surgical experience were factors statistically evaluated for possible associations with capsular penetration during surgery, conversion, surgical time, duration of hospital stay, death prior to discharge, mass recurrence, and survival time. RESULTS: 155 dogs had left-sided tumors, and 100 had right-sided tumors. Conversion to an open approach was performed in 9.4% of cases. Capsular penetration (19.2%) and major hemorrhage (5.4%) were the most prevalent intraoperative complications. Of the dogs operated on, 94.9% were discharged from the hospital. Lesion side, portion of the gland affected, and surgeon experience influenced surgical time. Conversion rate increased with increasing body condition score and lesion size. Risk of death prior to discharge increased with increasing lesion size. Risk of conversion and death prior to discharge were lower when performed by more experienced surgeons. Capsular penetration during LA increased the risk of tumor recurrence. CLINICAL RELEVANCE: LA for resection of unilateral adrenal masses is associated with excellent outcomes in experienced centers. Surgeons with greater experience with LA have lower surgical times, conversion rates, and risk of death prior to discharge.

Risk factors influencing death prior to discharge in 302 dogs undergoing unilateral adrenalectomy for treatment of primary adrenal gland tumours.

Adrenalectomies for canine adrenal tumours are associated with peri-operative morbidity and mortality. Objectives of this study included assessing the prognostic value of tumour- or surgery-related variables in predicting peri-operative mortality and overall survival in dogs undergoing adrenalectomies for primary adrenal tumours as well as pre-treatment with phenoxybenzamine on survival to discharge with pheochromocytomas specifically. A multi-institutional retrospective cohort study was performed across nine institutions. Electronic medical record searches identified 302 dogs which met the inclusion criteria. Data collected included dog-related, tumour-related, treatment-related, surgery-related, and outcome variables. Univariate and multivariable logistic regression and cox proportional hazards models were used to identify variables associated with death prior to discharge and tumour-related survival. Overall, 87% of dogs survived to discharge with a tumour-related survival time of 3.96 years. Post-operative complications were reported in 25%. Increased surgical time (p = 0.002) and pre-surgical medical treatment other than phenoxybenzamine (p = 0.024) were significantly associated with increased peri-operative mortality while ureteronephrectomy (p = 0.021), post-operative pancreatitis (p = 0.025), and post-operative aspiration pneumonia (p < 0.001) were significantly associated with decreased overall survival. Phenoxybenzamine pretreatment had no effect on peri-operative mortality. Thirty-seven of 45 (82%) dogs with pheochromocytomas not pretreated survived to discharge, and 50 of 59 (85%) dogs with pheochromocytomas pretreated with phenoxybenzamine survived to discharge (p = 0.730). This study provides information on risk factors for death prior to discharge and tumour-related survival that may help guide clinical management and owner expectations. In addition, the study findings challenge the previously reported benefit of phenoxybenzamine for pretreatment of dogs undergoing adrenalectomies for pheochromocytomas.

Bilateral, single-session, laparoscopic adrenalectomy was associated with favorable outcomes in a cohort of dogs.

OBJECTIVE: To report perioperative characteristics and outcome following bilateral, single-session, laparoscopic adrenalectomy (BSSLA) in dogs. ANIMALS: Client-owned dogs (n = 6). CLINICAL PRESENTATION AND PROCEDURES: Medical records were reviewed and perioperative data collected, including preoperative diagnostic imaging, operative details, complications, and need for conversion to open laparotomy. Bilateral, single-session, laparoscopic adrenalectomy was performed on the right or left side with a standard 3- or 4-portal transperitoneal technique. The dog was repositioned to contralateral recumbency, and laparoscopic adrenalectomy was repeated. Follow-up information was collected by telephone interviews with the owners and/or referring veterinarian. RESULTS: Median age and weight of dogs were 126 months and 14.75 kg, respectively. Contrast-enhanced CT (CECT) was performed in all dogs. Median maximal tumor diameter was 2.6 and 2.3 cm for the right and left-sided tumors, respectively. Median surgical and anesthesia times were 158 and 240 minutes, respectively. Conversion to open laparotomy was performed in 1 dog following renal vein laceration during initial adrenalectomy. Left adrenalectomy and ureteronephrectomy were performed, and the right adrenal tumor was left in situ. Cardiac arrest occurred in 1 dog following initial adrenalectomy (left); however, the dog was resuscitated successfully, and contralateral laparoscopic adrenalectomy was performed without complication. All dogs survived to hospital discharge. Follow-up ranged from 60 to 730 days (median, 264 days) for dogs that successfully underwent BSSLA. CLINICAL RELEVANCE: BSSLA was associated with favorable outcomes in this cohort of dogs. Laparoscopy may be considered in dogs with bilateral, modestly sized, noninvasive adrenal tumors.

Diagnosis, treatment and outcome of pheochromocytoma in a cat.

Pheochromocytoma in cats is a rare clinical condition characterised by the development of a secretory endocrine tumour that arises from the adrenal medulla. An 8-year-old castrated male, domestic shorthair cat was referred for further investigation of a 4-month history of progressive weight loss with normal appetite, polyuria/polydipsia, generalised weakness, and severe hypertension. Sonography and computed tomography of the abdomen disclosed a mass arising from the left adrenal gland. The contralateral adrenal gland was normal in size and shape. Results from a low dose dexamethasone suppression test and measurements of plasma aldosterone concentration and plasma renin activity ruled out a cortisol-secreting tumour and aldosteronoma. The clinical presentation made a sex-steroid secreting tumour unlikely. Increased plasma metanephrine and normetanephrine concentrations prioritised the differential diagnosis of pheochromocytoma. The cat underwent adrenalectomy of the left gland and histopathological diagnosis with immunohistochemical markers confirmed the diagnosis.

Surgical findings and outcomes after unilateral adrenalectomy for primary hyperaldosteronism in cats: a multi-institutional retrospective study.

CASE SERIES SUMMARY: Twenty-nine cats from different institutions with confirmed or highly suspected primary hyperaldosteronism treated by unilateral adrenalectomy were retrospectively included in this study. The most frequent clinical signs were lethargy (n = 20; 69%) and neck ventroflexion (n = 17; 59%). Hypokalaemia was present in all cats, creatinine kinase was elevated in 15 and hyperaldosteronism was documented in 24. Hypertension was frequently encountered (n = 24; 89%). Preoperative treatment included potassium supplementation (n = 19; 66%), spironolactone (n = 16; 55%) and amlodipine (n = 11; 38%). There were 13 adrenal masses on the right side, 15 on the left and, in one cat, no side was reported. The median adrenal mass size was 2 × 1.5 cm (range 1-4.6 × 0.4-3.8); vascular invasion was present in five cats, involving the caudal vena cava in four cats and the renal vein in one. Median duration of surgery was 57 mins. One major intraoperative complication (3%) was reported and consisted of haemorrhage during the removal of a neoplastic thrombus from the caudal vena cava. In 4/29 cats (14%), minor postoperative complications occurred and were treated medically. One fatal complication (3%) was observed, likely due to disseminated intravascular coagulation. The median duration of hospitalisation was 4 days; 97% of cats survived to discharge. The potassium level normalised in 24 cats within 3 months of surgery; hypertension resolved in 21/23 cats. Follow-up was available for 25 cats with a median survival of 1082 days. Death in the long-term follow-up was mainly related to worsening of comorbidities. RELEVANCE AND NOVEL INFORMATION: Adrenalectomy appears to be a safe and effective treatment with a high rate of survival and a low rate of major complications. Long-term medical treatment was not required.

Stereotactic body radiation therapy as an alternative to adrenalectomy for the treatment of pheochromocytomas in 8 dogs.

The objective of this report is to describe the use and outcome of stereotactic body radiation therapy (SBRT) for treatment of pheochromocytomas in 8 dogs. Pheochromocytomas are an uncommon but challenging tumour to manage. Adrenalectomy is the standard of care for treatment of pheochromocytomas in both animals and humans; however, unpredictable catecholamine secretion from the tumour and vascular and local invasion of the tumour and thrombi can pose life-threatening perioperative and anaesthetic risks. SBRT has been investigated as an alternative to adrenalectomy in human patients with pheochromocytomas. Eight dogs with clinical signs, an adrenal mass, and cytology and/or urine normetanephrine/creatinine ratios consistent with pheochromocytoma were treated with SBRT in lieu of adrenalectomy. Three dogs presented with acute hemoabdomen. Seven dogs had caval tumour invasion, 3 with extension into the right atrium. Following SBRT, all dogs had complete resolution of clinical signs and reduced urine normetanephrine/creatinine ratio and/or tumour size. No significant anaesthetic complications were encountered. Acute radiation toxicity was limited to grade I gastrointestinal signs in 3 dogs and resolved within 1-2 days of symptomatic therapy. Five of 8 dogs were alive at the time of follow up, with a median follow up time of 25.8 months. SBRT resulted in a favourable outcome and mitigated the life-threatening risks of adrenalectomy in these 8 dogs. SBRT may be a safe and effective alternative to adrenalectomy for pheochromocytomas in dogs with non-resectable tumours, or for owners averse to the risks of surgery.

Short- and long-term survival after adrenalectomy in 53 dogs with pheochromocytomas with or without alpha-blocker therapy.

OBJECTIVE: To report data related to the short- and long-term survival of dogs undergoing adrenalectomy for pheochromocytoma, and to determine the influence of preoperative alpha-blocker therapy. STUDY DESIGN: Retrospective. ANIMALS: Fifty-three dogs. METHODS: Medical records were reviewed for dogs diagnosed with pheochromocytoma and treated with adrenalectomy between 2010 and 2020. Preoperative management, imaging studies, intraoperative cardiovascular instability, complications, and procedural information were recorded. When applicable, duration of survival and cause of death, time to recurrence or metastasis, and postoperative complications were recorded. RESULTS: During anesthesia, a hypertensive episode was documented in 46/53 dogs and arrhythmias were recorded in 16/53 dogs. Of these, 37/46 hypertensive dogs and 11/16 dogs with arrhythmias were treated with an alpha-blocker before surgery. Intraoperative systolic blood pressures reached higher levels by a magnitude of nearly 20% in dogs that were treated preoperatively with an alpha-blocker (P = .01). All dogs survived surgery and 44 survived to discharge. Follow up ranged from 6 to 1653 days (median 450 days). Median survival time for dogs discharged from the hospital was 1169 days (3.2 years). Recurrence and metastasis were suspected in 3 and 8 dogs, respectively. CONCLUSION: Most dogs survived the immediate postoperative period and achieved long-term survival with a low reported incidence of tumor recurrence or metastasis. Preoperative alpha-blocker therapy was not associated with increased survival. CLINICAL SIGNIFICANCE: The favorable outcomes reported in this study should be taken into consideration when discussing treatment options for dogs with pheochromocytomas. This study provides no evidence to support preoperative alpha-blocker therapy.

Update on Adrenalectomy.

Surgical removal is the standard of care for adrenal tumors greater than 2.0 cm diameter. For tumors smaller than 2.0 cm, imaging techniques evaluating patterns of contrast washout may offer a promising avenue for early identification of adrenal malignancy. Pretreatment of pheochromocytoma with phenoxybenzamine is associated with reduced surgical mortality risk. Surgical technique can be laparoscopic or open, depending on tumor anatomy and the experience of the surgeon. Vascular invasion is a contraindication for a laparoscopic technique. This review provides a summary of minimally invasive and open adrenalectomy techniques, including a discussion of management of vascular invasion and partial cavectomy.

C-kit, flt-3, PDGFR-ß, and VEGFR2 expression in canine adrenal tumors and correlation with outcome following adrenalectomy.

The objective of this retrospective study was to evaluate the expression of receptor tyrosine kinases (RTKs) in canine adrenal tumors and correlate this expression with features of tumor aggressiveness and survival in dogs undergoing adrenalectomy. Forty-three canine adrenal tumors were evaluated for expression of c-kit, fms-like tyrosine kinase 3 (flt-3), platelet-derived growth factor receptor-ß (PDGFR-ß), and vascular endothelial growth factor receptor 2 (VEGFR2) using immunohistochemistry. Tumor RTK staining characteristics were compared to normal adrenals. Medical records were reviewed for data regarding patient outcome and tumor characteristics. Expression of c-kit, flt-3, PDGFR-ß, and VEGFR2 was detected in 26.9%, 92.3%, 96.2%, and 61.5% of cortical tumors and 0%, 63.2%, 47.4%, and 15.8% of pheochromocytomas, respectively. Expression of RTKs was not significantly increased when compared to normal adrenals and did not correlate with survival after adrenalectomy. Receptor tyrosine kinases are not overexpressed in canine adrenal tumors compared to normal adrenal tissue. Therapeutic inhibition of these receptors may still represent an effective approach in cases where receptor activation is present.

L'objectif de cette étude rétrospective était d'évaluer l'expression des récepteurs tyrosine kinases (RTKs) dans les tumeurs surrénales canines et de corréler cette expression avec des caractéristiques d'agressivité tumorale et de survie chez les chiens subissant une surrénalectomie.Quarante-trois tumeurs surrénales canines ont été évaluées pour l'expression de c-kit, de la tyrosine kinase 3 de type fms (flt-3), du récepteur du facteur de croissance dérivé des plaquettes-ß (PDGFR-ß) et du récepteur du facteur de croissance endothélial vasculaire 2 (VEGFR2) par immunohistochimie. Les caractéristiques de coloration de la tumeur RTK ont été comparées à celles des surrénales normales. Les dossiers médicaux ont été examinés pour les données concernant les résultats des patients et les caractéristiques de la tumeur. L'expression de c-kit, flt-3, PDGFR-ß et VEGFR2 a été détectée dans 26,9 %, 92,3 %, 96,2 % et 61,5 % des tumeurs corticales et 0 %, 63,2 %, 47,4 % et 15,8 % des phéochromocytomes, respectivement. L'expression des RTK n'était pas significativement augmentée par rapport aux surrénales normales et n'était pas corrélée avec la survie après surrénalectomie. Les récepteurs tyrosine kinases ne sont pas surexprimés dans les tumeurs surrénales canines par rapport au tissu surrénalien normal. L'inhibition thérapeutique de ces récepteurs peut encore représenter une approche efficace dans les cas où l'activation du récepteur est présente.(Traduit par Docteur Serge Messier).

Retrospective study of aldosterone and progesterone secreting adrenal tumors in 10 cats.

BACKGROUND: Primary hyperaldosteronism caused by adrenal neoplasia has been well described in cats. Multiple corticosteroid abnormalities occur in a subset of affected cats, but characterizations of this syndrome are limited to several case reports. OBJECTIVES: To describe a series of cats with adrenal tumors secreting aldosterone and additional corticosteroids. ANIMALS: Ten cats with multiple corticosteroid secreting adrenocortical tumors. METHODS: Retrospective case series. Medical records of cats with adrenal tumors secreting both aldosterone and progesterone were identified. Data concerning historical findings, clinicopathologic features, treatments, and outcomes were retrieved from medical records. RESULTS: All 10 cats had diabetes mellitus in addition to biochemical features of hyperaldosteronism such as hypokalemia. High corticosterone concentrations were observed in all 3 cats in which this corticosteroid was measured. Ultrasound examinations revealed unilateral adrenal tumors in all 10 cases, and the contralateral adrenal gland was either atrophied or not identified in 5 cats. Three of 4 cats developed hypoadrenocorticism after surgical adrenalectomy. Three cats achieved diabetic remission after adrenalectomy. Two cats treated with adrenalectomy survived >1 year, 1 cat survived 6.5 months, and 1 cat was alive 5.5 months after diagnosis. Survival >1 year occurred in 2 of 4 cats treated with medical management alone. Two cats were not treated. CONCLUSIONS AND CLINICAL IMPORTANCE: The presence of multiple corticosteroid abnormalities should be considered in cats with aldosterone secreting adrenal tumors, especially those with concurrent diabetes mellitus. Both surgical and medical management can result in long-term survival, although diabetic remission was documented only in cats undergoing adrenalectomy.

Renal venotomy for thrombectomy and kidney preservation in dogs with adrenal tumors and renal vein invasion.

OBJECTIVE: To describe the surgical technique and report the outcomes of adrenalectomy and thrombus removal with kidney preservation by renal venotomy in a population of dogs with adrenal tumors and vascular invasion into the renal vein (RV) and caudal vena cava (CVC). STUDY DESIGN: Short case series. ANIMALS: Five client-owned dogs that underwent adrenalectomy. METHODS: Dogs with adrenal tumors and vascular invasion into the RV and CVC were retrospectively enrolled in this multi-institutional study. Renal venotomy was performed at the time of adrenalectomy for tumor thrombus removal. Recorded data included signalment, clinical signs and results of laboratory testing, physical examination findings, diagnostic imaging results, surgical technique, surgical time, surgical complications, and outcome. RESULTS: Tumor thrombus was removed by renal venotomy in five dogs. In one dog with an ectopic adrenal tumor located ventral to the left kidney, the thrombus was occluding 90% of caval flow, and a small caval venotomy was required to remove it. Kidney preservation was achieved in all dogs. No significant intraoperative or postoperative complications occurred, and all dogs were discharged 3 to 4 days postoperatively. Median surgical time was 125 minutes (range, 80-210). At the end of the study, four dogs were alive without signs of recurrence, while one dog died of a suspected pulmonary embolism at 510 days. Median follow-up was 510 days (range, 279-890). CONCLUSION: Renal venotomy is feasible for thrombectomy in dogs with adrenal tumors and RV invasion and allowed for the preservation of the kidney in this case series, thus limiting perioperative morbidity.

A multi-organ infection involving a left adrenal gland abscess in a diabetic dog.

A 14-year-old, intact male, American cocker spaniel dog was presented with a 5-day history of lethargy, inappetence, loose stools, abdominal pain, and hematuria. The dog had a 4-year history of diabetes mellitus and was in remission for immune-mediated hemolytic anemia. Abdominal ultrasonography and computed tomography scan revealed diffuse left adrenomegaly, splenic nodules, prostatomegaly, bilateral testicular cysts, and a hepatic mass. The dog underwent an exploratory laparotomy and a left adrenalectomy. Histopathology of the left adrenal gland was consistent with an adrenal abscess. To the authors' knowledge, this is the first reported case of an adrenal gland abscess in a dog. Key clinical message: This case highlights the potential for multi-organ infections in uncontrolled diabetic patients with non-specific clinical signs.

Une infection multi-organes impliquant un abcès de la glande surrénale gauche chez un chien diabétique. Un cocker américain mâle de 14 ans, intact, a été présenté avec de la léthargie, de l'inappétence, des selles molles, des douleurs abdominales et de l'hématurie depuis 5 jours. Le chien avait une histoire de 4 ans de diabète sucré et était en rémission pour une anémie hémolytique à médiation immunitaire. L'échographie abdominale et la tomodensitométrie ont révélé une adrénomégalie diffuse gauche, des nodules spléniques, une prostatomégalie, des kystes testiculaires bilatéraux et une masse hépatique. Le chien a subi une laparotomie exploratoire et une ablation de la surrénale gauche. L'histopathologie de la glande surrénale gauche était compatible avec un abcès surrénalien. À la connaissance des auteurs, il s'agit du premier cas signalé d'abcès des glandes surrénales chez un chien.Message clinique cléCe cas met en évidence le potentiel d'infections multi-organes chez les patients diabétiques non maitrisés présentant des signes cliniques non spécifiques.(Traduit par Dr Serge Messier).

A comparison of outcomes between laparoscopic and open adrenalectomies in dogs.

OBJECTIVE: To compare short- and long-term outcomes of dogs with adrenal tumors treated by adrenalectomy with laparoscopy or laparotomy. STUDY DESIGN: Retrospective study of dogs that underwent adrenalectomy with laparoscopy or laparotomy. SAMPLE POPULATION: Fourteen dogs treated with laparoscopic adrenalectomy (LA) and twenty-six dogs treated with open midline adrenalectomy (OA). METHODS: Dogs treated with LA were matched with 1 or 2 dogs treated with OA on the basis of histological nature, size, and side of the tumor. Intraoperative complications, postoperative complications, and long-term survival were compared between LA and OA. RESULTS: Intraoperative hypotension occurred in 2 of 14 (14.3%) dogs in the LA group and in 16 of 26 (61.5%) dogs in the OA group (P = .007). The surgical time was 69.8 ± 21.8 minutes for the LA group and 108.6 ± 42 minutes for the OA group (P = .0003). The hospitalization time was 39.3 ± 14.9 hours for the LA group and 46.3 ± 25.1 hours for the OA group (P = .1453). The 1- and 2-year survival rates were 77% and 77%, respectively, for the LA group and 77% and 66%, respectively, for the OA group (P = .6144). CONCLUSION: Laparoscopic adrenalectomy was associated with a shorter surgical time and a reduced incidence of hypotension compared with open adrenalectomy in this case-matched study. Short- and long-term outcomes were not affected by the surgical technique used to complete the adrenalectomy. CLINICAL SIGNIFICANCE: Laparoscopy can be recommended for adrenalectomy in dogs; however, appropriate case selection is required.

Retrospective evaluation of labetalol as antihypertensive agent in dogs.

BACKGROUND: To evaluate the effect on arterial blood pressure (ABP) of labetalol infusion as treatment for perioperative non nociceptive acute hypertension in dogs. The clinical records of dogs receiving intra or postoperative labetalol infusion were retrospectively reviewed. Invasive systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressure and heart rate (HR) before labetalol infusion (T0) and 15, 30, 45 and 60 min (T1, T2, T3 and T4 respectively) after infusion were retrieved. The dose rate of labetalol infusion and use of concurrently administered drugs that could have potentially affected ABP and/or HR were also recorded. ANOVA for repeated measures and Dunnett's multiple comparison test were used to determine the effect of labetalol on ABP and HR. Differences were considered significant when p < 0.05. RESULTS: A total of 20 dogs met the inclusion criteria, and hypertension was documented after craniotomy (12/20), adrenalectomy (4/20) and other procedures (4/20). Five dogs received labetalol intraoperatively, 14 postoperatively, and 1 during the surgical procedure and recovery. Median infusion duration and rate were 463 (60-2120) minutes and 1.1 (0.2-3.4) mg/kg/h respectively. Median loading dose was 0.2 (0.2-0.4) mg/kg. Labetalol produced a significant decrease in SAP and DAP at all time points compared to T0 (p < 0.05), while the effect was not significant at T1 for MAP (p = 0.0519). Median maximum MAP decrease was 31 (20-90) mmHg. Heart rate did not increase significantly during treatment (p = 0.2454). Acepromazine given before or during labetalol treatment did not reduce significantly ABP (p = 0.735). CONCLUSIONS: Labetalol produced a reliable and titratable decrease in ABP with non significant increase in HR.

Short-term outcome of adrenalectomy in dogs with adrenal gland tumours that did not receive pre-operative medical management.

OBJECTIVE: Review medical records of dogs that underwent adrenalectomy without pre-operative medical management, to examine the peri-operative morbidity and mortality. DESIGN: Case series of 65 dogs. METHODS: Medical records were reviewed. Features recorded included the histologic diagnosis, intra-operative hypertension or tachycardia, requirement for cavotomy, administration of intra- and post-operative corticosteroids, performance of additional surgery and the occurrence of peri-operative complications. Dogs requiring emergency surgery were excluded. RESULTS: Of the 65 dogs, 49 had adrenocortical tumours (11 bilateral), 13 had pheochromocytomas (one bilateral) and three dogs had tumours in both adrenal glands of a different tumour type. Five dogs had caudal vena cava invasion and 33 had additional procedures performed at the same time. Mortality occurred in 1/65 dogs (1.5%; 95% CI 0.03%-8.2%), major complications were identified in 1/65 dogs (1.5%; 95% CI 0.03%-8.2%) and minor complications occurred in 10/53 dogs (15%; 95% CI 8.6%-26%). CONCLUSION: Based on the limited peri-operative complications and low mortality in this pre-operatively untreated cohort, and based on critique of the available literature, the added value afforded by pre-operative treatment is questioned. With appropriate management, adrenal tumours can be removed with few peri-operative complications and low mortality.

Outcome in dogs undergoing adrenalectomy for small adrenal gland tumours without vascular invasion.

Veterinary studies have reported the outcome of adrenalectomies in dogs; however, these studies typically include a wide variety of adrenal tumour sizes, including cases with or without vascular invasion. The purpose of this study was to report outcome in a cohort of dogs with histologically confirmed small adrenal tumours without vascular invasion treated with adrenalectomy. This retrospective study was conducted using data from the University of Florida and University of California-Davis databases between 2010 and 2017. Dogs were included if they underwent excision of an adrenal gland tumour with a maximal diameter ≤ 3 cm, without evidence of vascular invasion to any location as assessed via computed tomography. Fifty-one dogs met the inclusion criteria. The short-term survival rate of dogs undergoing adrenalectomy was 92.2%, and one-year disease-specific survival was 83.3%. Twenty-eight of 51 (54.9%) dogs were diagnosed with a malignancy. Minor complications were observed commonly intra-operatively and post-operatively. Major complications were observed in six dogs, and included sudden death, respiratory arrest, acute kidney injury, haemorrhage, hypotension and aspiration pneumonia. Short-term mortality occurred in four dogs. Sudden death and haemorrhage were the most common major complications leading to death. While adrenalectomy is sometimes controversial because of the high perioperative mortality rates previously reported, the results of this study support that adrenalectomy for small tumours with no vascular invasion can be performed with low risk.