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.

Comparison of median sternotomy closure-related complication rates using orthopedic wire or suture in dogs: A multi-institutional observational treatment effect analysis.

OBJECTIVE: To determine and compare median sternotomy (MS) closure-related complication rates using orthopedic wire or suture in dogs. STUDY DESIGN: Multi-institutional, retrospective observational study with treatment effect analysis. ANIMALS: 331 client-owned dogs, of which 68 were excluded. METHODS: Medical records of dogs with MS were examined across nine referral centers (2004-2020). Signalment, weight, clinical presentation, surgical details, complications, and outcomes were recorded. Follow-up was performed using patient records and email/telephone contact. Descriptive statistics, treatment effect analysis and logistic regression were performed. RESULTS: Median sternotomy closure was performed with wire in 115 dogs and suture in 148. Thirty-seven dogs experienced closure-related complications (14.1%), 20 in the wire group and 17 in the suture group. Twenty-three were listed as mild, four as moderate and 10 as severe. Treatment effect analysis showed a mean of 2.3% reduction in closure-related complications associated with using suture versus wire (95% CI: -9.1% to +4.5%). In multivariable logistic regression, the only factor associated with increased risk of closure-related complications was dog size (p = .01). This effect was not modified by the type of closure used (interaction term: OR = 0.99 [95% CI: 0.96/1.01]). CONCLUSION: The incidence of closure-related complication after MS was low compared to previous reports. The likelihood of developing a closure-related complication was equivalent between sutures and wires, independent of dog size, despite a higher proportion of complications seen in larger dogs (≥20 kg). CLINICAL SIGNIFICANCE: Use of either orthopedic wire or suture appear to be an appropriate closure method for sternotomy in dogs of any size.

Closure-related complications after median sternotomy in cats: 26 cases (2010-2020).

OBJECTIVES: The aim of this study was to determine closure-related complications and outcome after median sternotomy (MS) in cats. METHODS: This was a retrospective, multicentric study. The medical records of cats undergoing MS from six referral hospitals were reviewed (2010-2020). Data retrieved included signalment, history, presenting complaints, surgery, patient outcomes and complications. Follow-up was performed via patient records and email/telephone contact with both owners and referring veterinarians. Descriptive statistics were performed. RESULTS: Data on 36 cats were collected; four were excluded due to insufficient follow-up and six died less than 5 days after surgery. Twenty-six cats survived to discharge (survival rate 81%). Three cats had a full sternotomy (FS) performed and 23 cats a partial sternotomy (PS). Of the cats that underwent a PS, six included the manubrium (PSM) and three included the xyphoid process. For 14 cats, the length of sternotomy was unknown. Sternotomy closure was performed with suture in all cats. Two cats (7.7%) developed closure-related complications, both after PSM, during the long-term follow-up, one mild, slightly displaced sternal fracture and one severe, sternal dehiscence (without skin wound dehiscence) requiring revision surgery. No seroma, surgical site infection or wound dehiscence occurred. The most common reason for MS was the presence of a thoracic mass (17/26; 65%), with thymoma being the most common (11/17; 65%). CONCLUSIONS AND RELEVANCE: MS has a low closure-related complication risk in cats when compared with dogs. Complications in cats present differently to what has been previously described in dogs.

Complications associated with and outcome of surgical intervention for treatment of esophageal foreign bodies in dogs.

OBJECTIVE: To identify complications associated with and short- and long-term outcomes of surgical intervention for treatment of esophageal foreign bodies (EFBs) in dogs. ANIMALS: 63 client-owned dogs. PROCEDURES: Patient records from 9 veterinary hospitals were reviewed to identify dogs that underwent surgery for removal of an EFB or treatment or an associated esophageal perforation between 2007 and 2019. Long-term follow-up data were obtained via a client questionnaire. RESULTS: 54 of the 63 (85.7%) dogs underwent surgery after an unsuccessful minimally invasive procedure or subsequent evidence of esophageal perforation was identified. Esophageal perforation was present at the time of surgery in 42 (66.7%) dogs. Most dogs underwent a left intercostal thoracotomy (37/63 [58.7%]). Intraoperative complications occurred in 18 (28.6%) dogs, and 28 (50%) dogs had a postoperative complication. Postoperative complications were minor in 14 of the 28 (50%) dogs. Dehiscence of the esophagotomy occurred in 3 dogs. Forty-seven (74.6%) dogs survived to discharge. Presence of esophageal perforation preoperatively, undergoing a thoracotomy, and whether a gastrostomy tube was placed were significantly associated with not surviving to discharge. Follow-up information was available for 38 of 47 dogs (80.9%; mean follow-up time, 46.5 months). Infrequent vomiting or regurgitation was reported by 5 of 20 (25%) owners, with 1 dog receiving medication. CLINICAL RELEVANCE: Results suggested that surgical management of EFBs can be associated with a high success rate. Surgery should be considered when an EFB cannot be removed safely with minimally invasive methods or esophageal perforation is present.

Complications and outcome of cats with congenital extrahepatic portosystemic shunts treated with thin film: Thirty-four cases (2008-2017).

BACKGROUND: Congenital extrahepatic portosystemic shunts (CEHPSS) are rare in cats. Outcome after attenuation of CEHPSS with thin film has been described in a small number of cases. OBJECTIVES: To describe the clinical presentation, postoperative complications, and outcome of cats treated with thin film to attenuate CEHPSS. ANIMALS: Thirty-four cats with CEHPSS were identified from the database of 3 institutions over 9 years. METHODS: Retrospective study. Medical records were reviewed to identify cats with a diagnosis of a CEHPSS that underwent surgical attenuation. Congenital extrahepatic portosystemic shunts were suspected from clinical signs, clinicopathologic findings, and diagnostic imaging, and confirmed at exploratory laparotomy. Cats treated with thin film band attenuation were included. Postoperative complications and follow-up were recorded. RESULTS: Complications were recorded in 11 of 34 cats. Deaths related to CEHPSS occurred in 6 of 34; 4 cats did not survive to discharge. Persistent seizures were the cause of death in 4 cats. Seizures were recorded in 8 of 34 cats after surgery; all these cats received preoperative antiepileptic drugs. Serum bile acid concentrations normalized in 25 of 28 of the cats for which data was available. Three cats had persistently increased serum bile acid concentrations and underwent a second exploratory laparotomy. One had a patent shunt, the other 2 had multiple acquired portosystemic shunts. Median follow-up was 8 months (0.5-84 months). CONCLUSIONS AND CLINICAL IMPORTANCE: Congenital extrahepatic portosystemic shunts attenuation using thin film in cats carries a good short- and mid-term prognosis if they survive the postoperative period. Seizures were the most common cause of death.

Prevalence, Risk Factors and Outcome of Postoperative Tibial Tuberosity Fractures in Dogs Undergoing Triple Tibial Osteotomy Surgery.

OBJECTIVE: The aim of this study was to report the prevalence and to identify the risk factors associated with postoperative tibial tuberosity fracture following a triple tibial osteotomy. This article also evaluates the outcome of these patients treated conservatively. MATERIALS AND METHODS: Medical records of 100 dogs (113 limbs) that underwent triple tibial osteotomy procedure were evaluated. Information obtained included signalment, preoperative, immediate postoperative and 6-week postoperative radiographic findings, intraoperative and postoperative complications. Long-term outcome was assessed using an owner questionnaire. RESULTS: Postoperative tibial tuberosity fracture was identified in 25/113 stifles. The only variable associated with the presence or absence of postoperative tibial tuberosity fracture within 6 weeks of surgery was postoperative cortical hinge width (CHW) or an indexed value of CHW to tibial width (TW). Using either a cut-off value of CHW of ≥ 5.5 mm or a cut-off value of CHW/TW of ≥ 0.21, only 1/27 stifle in our study developed tibial tuberosity fracture. Long-term owner evaluation of outcome was considered excellent or good in 65/70 stifles. CONCLUSION: A narrow CHW at the distal cortical attachment of the tibial crest had a strong association with the development of postoperative tibial tuberosity fracture. No other patient or surgical variables were associated with tibial tuberosity fracture. Patients that developed tibial tuberosity fracture and were conservatively managed did not have a worse clinical outcome than patients that did not develop tibial tuberosity fracture.

Ventral stabilization of thoracic kyphosis through bilateral intercostal thoracotomies using SOP (String of Pearls) plates contoured after a 3-dimensional print of the spine.

OBJECTIVE: To describe a novel vertebral body stabilization and report its outcome in dogs with thoracic kyphosis and secondary myelopathy. STUDY DESIGN: Case series. ANIMALS: Six pugs with thoracic kyphosis and secondary myelopathy. METHODS: Medical records (2012-2017) of dogs with chronic progressive pelvic limb ataxia and ambulatory proprioceptive paraparesis due to thoracic kyphosis were reviewed. Dogs were evaluated via MRI and computed tomography. A 3-dimensional print of the kyphotic vertebral segment was used to precontour the SOP (String of Pearls) plates. Bilateral double, dorsal intercostal thoracotomies were performed to place precontoured SOP on the vertebral bodies. Long-term (6-16 months) clinical outcome was determined on the basis of neurological scoring (NS) and owner questionnaire. RESULTS: The only intraoperative complication consisted of a lung laceration due to preexisting adhesions. Postoperative complications included seroma formation (n = 2) and incidental radiographic evidence of screw breakage (n = 2). NS at presentation ranged between 2 and 4 and improved to 1 at long-term follow-up in all dogs but 1 (NS = 2). All owners felt that their dog had excellent quality of life at follow-up. CONCLUSION: In spite of the challenging local anatomy, all dogs undergoing vertebral stabilization with SOP placement experienced a good clinical outcome. CLINICAL SIGNIFICANCE: Stabilization of vertebral bodies with precontoured SOP placed through bilateral thoracotomies may be considered as a treatment option for dogs with thoracic kyphosis and secondary myelopathy.

Evaluation of osteotomy accuracy and rotational and angular alignment for cranial closing wedge ostectomy performed with and without alignment aids.

OBJECTIVE: To (1) investigate the use of K-wires as alignment aids for cranial closing wedge ostectomy (CCWO) and (2) evaluate their effect on osteotomy accuracy and angular/rotational alignment. STUDY DESIGN: Cadaveric study. ANIMALS: Cadaveric pelvic limbs (n = 20). METHODS: CCWO was performed with and without alignment aids on 20 cadaveric pelvic limbs. CT scans were performed pre- and post-operatively to evaluate tibial torsion and valgus/varus deformity. Digital photographs of the ostectomized bone wedges were used to assess divergence of the 2 osteotomies, and the area of the medial and lateral aspects measured to assess osteotomy angulation within the dorsal plane. RESULTS: Osteotomy divergence angle, the difference between the area of the medial and lateral aspects of the ostectomized wedges, and the difference between the pre- and post-operative angles of valgus/varus deformity were all significantly smaller for the alignment aid group. The difference in pre- and post-operative tibial torsion was not significantly different between groups. CONCLUSIONS: K-wires can be used successfully as alignment aids during CCWO and help to create a significantly more orthogonal osteotomy. This allows a significant reduction in the difference between the preoperative and postoperative angles of valgus or varus, which may reduce the risk of developing a clinically important iatrogenically introduced valgus/varus deformity postoperatively.

In vitro comparison of mechanical and degradation properties of equivalent absorbable suture materials from two different manufacturers.

OBJECTIVE: To compare the mechanical, knotting, and absorption properties of 3 synthetic absorbable suture materials (polyglactin 910, polydioxanone, poliglecaprone 25) from 2 different manufacturers (Huaiyin Medical Instruments Co. Ltd. and Ethicon Inc.). SAMPLE POPULATION: Suture material samples from the same manufacturing lot for each suture type and manufacturer. METHODS: Part 1: 10 samples of each suture were incubated in bovine serum and tested for ultimate load and stiffness at days 0, 1, 7, 14, 21, and 28. Part 2: 10 knotted samples were similarly evaluated, without incubation. RESULTS: Huaiyin polydioxanone had a greater (P<.001) ultimate load on days 0, 1, and 7; and a consistently greater stiffness for the duration of the study, compared with the Ethicon polydioxanone. Ethicon poliglecaprone 25 had a greater ultimate load on days 0, 1, 7 (P<.001); on day 21 Huaiyin had a greater ultimate load. Ethicon poliglecaprone had greater stiffness on days 0, 1, 7 (P<.001). Ethicon polyglactin 910 had a greater (P<.001) ultimate load at all times and a greater stiffness (P<.001) at days 0, 1, 7, and 14 compared with Huaiyin polyglactin 910. Huaiyin polydioxanone and polyglactin 910 had greater knot breaking strengths than Ethicon equivalents (P<.001). CONCLUSION: Differences in mechanical properties exist between nominally identical suture materials from different manufacturers.

Uterine horn torsion in a non-gravid cat.

An 11-year-old female domestic shorthair cat with a previous history of having been spayed, presented with signs of abdominal distension, lethargy and anorexia of 1 week's duration. On the basis of radiological and ultrasonographic findings a tentative diagnosis of pyometra was made. Exploratory coeliotomy revealed a 900 degrees left horn uterine torsion along the longitudinal axis. Ovariohysterectomy was performed without correction of the torsion. To the authors' knowledge this is the first case report of uterine torsion in a non-gravid cat.