To determine the frequency and severity of thrombocytosis and thromboelastographic evidence of hypercoagulability during the first 2 weeks after splenectomy in dogs with splenic masses and to investigate relationships between platelet counts and thromboelastography values.
34 dogs undergoing splenectomy for splenic masses.
Blood samples for platelet counts and thromboelastography were obtained at induction of anesthesia (day 0) prior to splenectomy and on days 2, 7, and 14.
Mean platelet counts were 167.9 × 103/μL, 260.4 × 103 μ/L, 715.9 × 103/μL, and 582.2 × 103/μL on days 0, 2, 7, and 14, respectively, and were significantly higher at all postoperative assessment points than on day 0. Thrombocytosis was observed in 3% (1/34), 6% (2/33), 81% (21/26), and 69% (18/26) of dogs on days 0, 2, 7, and 14. Platelet counts > 1,000 × 103/μL were observed in 1 dog on day 2 and in 5 dogs on day 7. One or more thromboelastography values suggestive of hypercoagulability were observed in 45% (15/33), 84% (26/31), 89% (24/27), and 84% (21/25) of dogs on days 0, 2, 7, and 14. At each assessment point, higher platelet counts were correlated with thromboelastography values suggestive of hypercoagulability.
CONCLUSIONS AND CLINICAL RELEVANCE
Marked thrombocytosis and thromboelastography values suggestive of hypercoagulability were common during the first 2 weeks after splenectomy for the dogs of this study. If present, hypercoagulability could increase the risk for development of postsplenectomy thrombotic conditions such as portal system thrombosis and pulmonary thromboembolism.
Objective—To determine whether changes in presurgical plasma lactate concentration (before and after initial fluid resuscitation and gastric decompression) were associated with short-term outcome for dogs with gastric dilatation-volvulus (GDV).
Design—Retrospective case series.
Procedures—Medical records were reviewed, and signalment, history, resuscitative treatments, serial presurgical lactate concentrations, surgical findings, and short-term outcome were obtained for dogs with confirmed GDV.
Results—36 of 40 (90%) dogs with an initial lactate concentration ≤ 9.0 mmol/L survived, compared with only 13 of 24 (54%) dogs with a high initial lactate (HIL) concentration (> 9.0 mmol/L). Within HIL dogs, there was no difference in mean ± SD initial lactate concentration between survivors and nonsurvivors (10.6 ± 2.3 mmol/L vs 11.2 ± 2.3 mmol/L, respectively); however, there were significant differences in post-treatment lactate concentration, absolute change in lactate concentration, and percentage change in lactate concentration following resuscitative treatment. By use of optimal cutoff values within HIL dogs, survival rates for dogs with final lactate concentration > 6.4 mmol/L (23%), absolute change in lactate concentration ≤ 4 mmol/L (10%), or percentage change in lactate concentration ≤ 42.5% (15%) were significantly lower than survival rates for dogs with a final lactate concentration ≤ 6.4 mmol/L (91%), absolute change in lactate concentration > 4 mmol/L (86%), or percentage change in lactate concentration > 42.5% (100%).
Conclusions and Clinical Relevance—Calculating changes in plasma lactate concentration following initial treatment in dogs with GDV may assist in determining prognosis and identifying patients that require more aggressive treatment.
Objective—To determine long-term outcome of dogs
with gallbladder mucocele.
Animals—30 dogs with gallbladder mucocele, including
23 that underwent cholecystectomy.
Procedure—Medical records were reviewed for signalment,
history, and clinical, ultrasonographic, and
surgical findings. Follow-up information was obtained
for all dogs that survived the perioperative hospitalization
Results—23 dogs had signs of systemic illness; 7 had
no clinical signs. Median values for serum activities of
alanine aminotransferase and alkaline phosphatase,
serum total bilirubin concentration, and total WBC
count were significantly higher among dogs with gallbladder
rupture than among dogs without rupture.
Sensitivity of sonography for detection of rupture was
85.7%. Overall perioperative mortality rate for dogs
that underwent cholecystectomy was 21.7%; mortality
rate was not significantly greater for dogs with rupture.
Aerobic bacteria were isolated from the bile or gallbladder
wall in 8.7% of dogs. All 18 dogs discharged
from the hospital had complete resolution of clinical
signs. In dogs that underwent in-hospital reexamination,
serum liver enzyme activities were significantly
decreased, compared with preoperative activities.
Persistent increases in serum activities of 1 or more
liver enzymes were detected in 9 of 12 dogs; 6 of 12
dogs had persistent abnormalities in hepatic
echogenicity. Mean follow-up period was 13.9 months.
Conclusions and Clinical Relevance—Results suggest
that cholecystectomy is an effective treatment
for gallbladder mucocele. Although perioperative mortality
rate is high, prognosis after discharge from the
hospital is excellent. Rupture of the gallbladder warrants
emergency surgical intervention but does not
preclude a positive outcome. (J Am Vet Med Assoc
Objective—To determine survival time for dogs with splenic hemangiosarcoma treated with splenectomy alone, identify potential prognostic factors, and evaluate the efficacy of adjuvant chemotherapy.
Design—Retrospective case series.
Procedures—Medical records were reviewed, long-term follow-up information was obtained, and survival data were analyzed statistically.
Results—154 dogs were treated with surgery alone, and 54 were treated with surgery and chemotherapy. Twenty-eight dogs received conventional chemotherapy, 13 received cyclophosphamide-based metronomic chemotherapy, and 13 received both conventional and metronomic chemotherapy. Median survival time of dogs treated with splenectomy alone was 1.6 months. Clinical stage was the only prognostic factor significantly associated with survival time. When the entire follow-up period was considered, there was no significant difference in survival time between dogs treated with surgery alone and dogs treated with surgery and chemotherapy. However, during the first 4 months of follow-up, after adjusting for the effects of clinical stage, survival time was significantly prolonged among dogs receiving any type of chemotherapy (hazard ratio, 0.6) and among dogs receiving both conventional and metronomic chemotherapy (hazard ratio, 0.4).
Conclusions and Clinical Relevance—Clinical stage was strongly associated with prognosis for dogs with splenic hemangiosarcoma. Chemotherapy was effective in prolonging survival time during the early portion of the follow-up period. Combinations of doxorubicin-based conventional protocols and cyclophosphamide-based metronomic protocols appeared to be more effective than either type of chemotherapy alone, but prolongations in survival time resulting from current protocols were modest.
Objective—To determine the perioperative mortality rate, causes of death, and risk factors for perioperative death in dogs undergoing splenectomy for splenic mass lesions.
Design—Retrospective case series.
Procedures—Medical records of dogs that underwent splenectomy for known splenic masses were reviewed. Perioperative mortality rate and causes of death were determined. Associations between potential prognostic factors and perioperative death were evaluated by multivariable logistic regression analysis.
Results—41 of 539 (7.6%) dogs died during the perioperative period. Thrombotic and coagulopathic syndromes and uncontrolled bleeding from metastatic lesions were the most common causes of death. Of the variables selected for multivariable analysis, platelet count at admission, whether PCV at admission was < 30%, and development of ventricular arrhythmias during surgery were significantly associated with outcome. For each decrease in platelet count of 10,000 platelets/μL, odds of death increased by approximately 6%. For dogs with PCV < 30%, odds of death were approximately twice those for dogs with PCV ≥ 30%, and for dogs that developed intraoperative arrhythmias, odds of death were approximately twice those for dogs that did not.
Conclusions and Clinical Relevance—Marked preoperative thrombocytopenia or anemia and development of intraoperative ventricular arrhythmias were identified as risk factors for perioperative death in dogs with splenic masses. The risk of death may be limited by efforts to prevent thrombotic and coagulopathic syndromes and to control all sources of intra-abdominal hemorrhage.
To develop a multivariable model and online decision-support calculator to aid in preoperative discrimination of benign from malignant splenic masses in dogs.
522 dogs that underwent splenectomy because of splenic masses.
A multivariable model was developed with preoperative clinical data obtained retrospectively from the records of 422 dogs that underwent splenectomy. Inclusion criteria were the availability of complete abdominal ultrasonographic examination images and splenic histologic slides or histology reports for review. Variables considered potentially predictive of splenic malignancy were analyzed. A receiver operating characteristic curve was created for the final multivariable model, and area under the curve was calculated. The model was externally validated with data from 100 dogs that underwent splenectomy subsequent to model development and was used to create an online calculator to estimate probability of splenic malignancy in individual dogs.
The final multivariable model contained 8 clinical variables used to estimate splenic malignancy probability: serum total protein concentration, presence (vs absence) of ≥ 2 nRBCs/100 WBCs, ultrasonographically assessed splenic mass diameter, number of liver nodules (0, 1, or ≥ 2), presence (vs absence) of multiple splenic masses or nodules, moderate to marked splenic mass inhomogeneity, moderate to marked abdominal effusion, and mesenteric, omental, or peritoneal nodules. Areas under the receiver operating characteristic curves for the development and validation populations were 0.80 and 0.78, respectively.
CONCLUSIONS AND CLINICAL RELEVANCE
The online calculator (T-STAT.net or T-STAT.org) developed in this study can be used as an aid to estimate the probability of malignancy in dogs with splenic masses and has potential to facilitate owners' decisions regarding splenectomy.
Objective—To determine whether multiple organ dysfunction syndrome (MODS) could be identified in dogs with sepsis secondary to gastrointestinal tract leakage, and whether the number of affected organ systems was significantly associated with mortality rate.
Design—Multicenter retrospective case series.
Procedures—Medical records for dogs treated surgically because of sepsis secondary to gastrointestinal tract leakage between 2003 and 2007 were reviewed. Sepsis was diagnosed on the basis of results of bacterial culture of peritoneal fluid, gross evidence of gastrointestinal tract leakage at surgery, or both. Renal dysfunction was defined as a ≥ 0.5 mg/dL increase in serum creatinine concentration after surgery. Cardiovascular dysfunction was defined as hypotension requiring vasopressor treatment. Respiratory dysfunction was defined as a need for supplemental oxygen administration or mechanical ventilation. Hepatic dysfunction was defined as a serum bilirubin concentration > 0.5 mg/dL. Dysfunction of coagulation was defined as prolonged prothrombin time, prolonged partial thromboplastin time, or platelet count ≤ 100,000/μL.
Results—89 (78%) dogs had dysfunction of 1 or more organ systems, and 57 (50%) dogs had MODS. Mortality rate increased as the number of dysfunctional organ systems increased. Mortality rate was 70% (40/57) for dogs with MODS and 25% (14/57) for dogs without.
Conclusions and Clinical Relevance—Results indicated that MODS, defined as dysfunction of at least 2 organ systems, can be identified in dogs with sepsis and that organ system dysfunction increased the odds of death.
To assess histologic evaluation of mandibular lymph nodes (MLNs) and medial retropharyngeal lymph nodes (MRLNs) for metastatic disease during tumor staging for dogs with oral malignant melanoma (OMM) and oral squamous cell carcinoma (OSCC).
Retrospective multi-institutional study.
27 dogs with OMM and 21 dogs with OSCC.
Medical record databases of 8 institutions were searched to identify dogs with OMM or OSCC that underwent unilateral or bilateral extirpation of the MLNs and MRLNs during the same procedure between January 2004 and April 2016. Information extracted from the records included signalment, primary mass location and size, diagnostic imaging results, histologic results for the primary tumor and all lymph nodes evaluated, and whether distant metastasis developed.
Prevalence of lymph node metastasis did not differ significantly between dogs with OMM (10/27 [37%]) and dogs with OSCC (6/21 [29%]). Distant metastasis was identified in 11 (41%) dogs with OMM and was suspected in 1 dog with OSCC. The MRLN was affected in 13 of 16 dogs with lymph node metastasis, and 3 of those dogs had metastasis to the MRLN without concurrent metastasis to an MLN. Metastasis was identified in lymph nodes contralateral to the primary tumor in 4 of 17 dogs that underwent contralateral lymph node removal.
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated histologic evaluation of only 1 MLN was insufficient to definitively rule out lymph node metastasis in dogs with OMM or OSCC; therefore, bilateral lymphadenectomy of the MLN and MRLN lymphocentra is recommended for such dogs.