Traumatic urothorax in a dog: a case report

Case series: Pleural effusion caused by urinary ultrafiltrate in two cats without evidence of urinary obstruction, trauma, or simultaneous perinephric pseudocysts

Objectives

To describe the diagnostic techniques, surgical treatments, and outcomes of two cats with recurrent pleural transudate caused by urinary ultrafiltrate.

Animals

Two cats without evidence of trauma, urinary tract obstruction, or concurrent perinephric pseudocysts that were evaluated and treated for recurrent pleural transudate caused by urinary ultrafiltrate.

Study design

Short case series.

Methods

Multiphase contrast CT scan revealed leakage of contrast media from the kidneys bilaterally into the retroperitoneal spaces in both cats. Renal scintigraphy performed in one cat revealed progressive accumulation of 99mTc diethylenetriamine penta-acetic acid (Tc-DTPA) in the pleural space. Exploratory laparotomy localized the leakage of fluid to renal capsular defects bilaterally in both cats. The retroperitoneum was incised bilaterally to promote fluid drainage into the peritoneum, and nephropexies were performed.

Results

One cat had long-term survival with recurrent, though decreasing volumes of, pleural effusion. The second cat was euthanized 16 days postoperatively for progressive renal disease.

Conclusion

The diagnosis of spontaneous urinary ultrafiltrate accumulation in the pleural space of cats without evidence of trauma, urinary tract obstruction, or concurrent perinephric pseudocysts has not previously been reported. The surgical correction described reduced but did not completely eliminate the rate of pleural effusion accumulation.

Successful resolution of urothorax secondary to non-traumatic uroabdomen in a cat managed with peritoneal dialysis as a bridge to surgery

Case summary

A 9-year-old neutered male domestic shorthair cat was presented for evaluation of severe hemodynamic collapse and suspected lower urinary tract disease. On admission, severe metabolic acidosis, hyperkalemia and azotemia, and electrocardiographic findings consistent with cardiotoxicity were identified. The diagnosis of uroabdomen was made based on abdominal fluid to plasma concentration ratios of creatinine and potassium. A central line catheter was placed percutaneously into the abdomen for peritoneal drainage and used for peritoneal dialysis as a bridge to surgery. Retrograde contrast cystography confirmed rupture of the urinary bladder. Point-of-care ultrasound of the chest postoperatively revealed the presence of mild pleural effusion. Echocardiography was then performed showing no evidence of cardiac disease. Pleural fluid analysis revealed a transudate with a creatinine ratio of 2.38 ([Creatinine]_{pleural fluid}/[Creatinine]_plasma), consistent with the diagnosis of urothorax. The cat recovered uneventfully from surgery and was monitored for signs of respiratory distress during the rest of its stay in hospital. The cat was discharged 4 days later and the pleural effusion resolved without further medical intervention.

Relevance and novel information

There is limited information on the causes of urothorax and uroabdomen management of feline patients. Pleural effusion is a complication observed in critically ill cats secondary to fluid overload, underlying cardiomyopathy, primary thoracic pathology or a combination of these. To our knowledge, this is the first report of urothorax in a cat secondary to non-traumatic uroabdomen. Careful monitoring of respiratory signs consistent with pleural space disease is recommended in cases of uroabdomen.

Resolution of nonurine transudative pleural effusion in a cat after removal of a hydronephrotic kidney

CASE DESCRIPTION A 3-year-old spayed female Bengal cat was evaluated because of a history of bilateral pleural effusion and hydronephrosis of the right kidney. CLINICAL FINDINGS Cytologic analysis of a pleural fluid sample revealed characteristics of a pure transudate with a high percentage of lymphocytes. Results of fluid biochemical testing were not consistent with urine or chyle. Serum biochemical analysis and echocardiography yielded no evidence of hypoalbuminemia or high hydrostatic pressure secondary to cardiac disease. Abdominal ultrasonography revealed hydronephrosis of the right kidney and hydroureter of the right ureter. TREATMENT AND OUTCOME Exploratory laparotomy with nephrectomy of the right kidney was performed. At the time of surgery, there was no evidence of communication between the retroperitoneal space and thoracic cavity. No other treatments were performed. No evidence of pleural fluid accumulation was detected 1 week after surgery, and no recurrence of clinical signs associated with pleural effusion was observed for > 1 year after surgery. CLINICAL RELEVANCE Transudative, or nonchylous lymphatic, pleural effusion secondary to intra-abdominal disease, but independent of a low plasma protein concentration, is uncommon in veterinary medicine. This case emphasized that urinary tract obstruction should be considered as a differential diagnosis for cats with pleural effusion when more common disorders are not identified. Even without evidence of direct communication between the abnormal kidney or retroperitoneal space and the pleural space, removal of the hydronephrotic kidney appeared curative.

Urothorax Associated with Uroperitoneum in a Dog Without Diaphragmatic Disruption

Accumulation of urine in the pleural space secondary to uroperitoneum with no disruption of the diaphragm appears to be a rare pathological condition. A 2 yr old male mixed-breed dog was referred with dyspnea and abdominal pain after a road traffic accident. Plain radiographs demonstrated pleural effusion and reduced serosal detail in the abdominal cavity that was compatible with fluid accumulation. Retrograde urethrography revealed a pelvic urethra rupture. Biochemical analysis of the pleural and abdominal fluid confirmed the diagnosis of urothorax and uroperitoneum. The dog underwent a prepubic urethrostomy and intensive care management. The dog was reported to be in good health after a follow up time of 10 mo. To the authors' knowledge, this is the first reported case of urothorax associated with uroperitoneum with no detectable defects of the diaphragm in a dog.

The impact of surgical timing and intervention on outcome in traumatized dogs and cats

OBJECTIVE

To review the relevant human and veterinary literature regarding the timing of surgical intervention for trauma patients and the impact on outcome.

DATA SOURCES

Original research, clinical studies, and review articles with no date restrictions from both human and veterinary literature.

HUMAN DATA SYNTHESIS

Despite extensive research into the ideal timing of surgical intervention for human trauma victims, debate is ongoing and views are still evolving. Prior to the 1970s, the standard of care consisted of delayed surgical treatment, as these patients were considered too ill to undergo surgery. Beginning in the 1970s, and continuing for nearly 2 decades, early definitive surgical treatment was recommended. The most recent evolution of human trauma management incorporates the concept of damage control surgery, which acknowledges the importance of early skeletal stabilization or laparotomy for reducing morbidity while attempting to avoid complications such as acute respiratory distress syndrome or multiple organ dysfunction syndrome.

VETERINARY DATA SYNTHESIS

Despite a relatively large amount of literature available regarding veterinary trauma, no evidence exists to provide the clinician guidance as to the ideal timing of surgery for trauma patients. With the exception of diaphragmatic hernia, no studies were identified that attempted to evaluate this variable.

CONCLUSIONS

Veterinary-specific studies are needed to evaluate the impact of surgical timing on outcome following trauma. The information that can be obtained from studies in this area can improve veterinary trauma care and may be used as models for human trauma care through translational applications.