Objective -To determine if absolute plasma lactate concentration or lactate clearance in dogs with septic peritonitis is associated with morbidity or mortality. Design -Retrospective cohort study from 2007 to 2012. Setting -University teaching hospital. Animals -Eighty-three dogs with septic peritonitis were included. Patients had at least 1 plasma lactate measurement during the course of the hospitalization. Results -Sixty-four percent of the patients survived to discharge, 22% were euthanized, and 14% died during hospitalization. Plasma lactate concentration >2.5 mmol/L on admission (29% of the patients) was associated with mortality (P = 0.001). Median admission plasma lactate concentration (n = 81) was significantly different between nonsurvivors (2.5 mmol/L, range 0.5-8.4) and survivors (1.4 mmol/L, range 0.5-9.7; P = 0.007). Admission plasma lactate concentration >4 mmol/L yielded a sensitivity of 36% and a specificity of 92% for nonsurvival. The inability to normalize plasma lactate concentration within 6 hours of admission (n = 10/24) yielded a sensitivity of 76% and specificity of 100% for nonsurvival. Postoperative hyperlactatemia (plasma lactate concentration >2 mmol/L; n = 18/76) had a sensitivity of 46% and specificity of 88% for nonsurvival. Persistent postoperative hyperlactatemia (n = 11/18) had a sensitivity of 92% and a specificity of 100% for nonsurvival. Lactate clearance less than 21% at 6 hours (n = 20) had a sensitivity of 54% and specificity of 91% for nonsurvival. Lactate clearance less than 42% at 12 hours (n = 18) had a sensitivity of 82% and a specificity of 100% for nonsurvival. Conclusions -Admission plasma lactate concentration and lactate clearance were good prognostic indicators in dogs with septic peritonitis. Crit Care 2015; 25(3): 388-395) (J Vet Emerg

Objectives The objective was to identify clinical or ultrasonographic results associated with ureteral obstruction or outcome in cats with azotaemia. Methods This was a retrospective cross-sectional study of cats with azotaemia (serum creatinine >180 μmol/l) that had ultrasonography of the urinary tract, ultrasound images available for review and received treatment for azotaemia. Cats with pre-renal azotaemia or urethral obstruction were excluded. Associations between clinical and ultrasonographic results and the dependent variables 'tentative diagnosis of ureteral obstruction', 'pyelography positive for ureteral obstruction' and 'death in hospital' were tested using binary logistic regression. Results In total, 238 cats satisfied the inclusion criteria. Median age was 7 years (range 2 weeks to 20 years), duration of clinical signs was 7 days (range 1 day to 6.3 years) and serum creatinine was 417 μmol/l (range 184-2100 μmol/l). Tentative diagnosis of ureteral obstruction in 92/238 (39%) cats was significantly associated with unilateral enlarged kidney on palpation, and dilated renal pelvis and calculi within the ureter on ultrasonography. Pyelography was performed in 49/92 (53%) cats (16 bilateral) with a tentative diagnosis of ureteral obstruction, and was positive for obstruction in 46/65 (71%) instances. No significant differences in ultrasonographic signs were found between cats with obstructed and non-obstructed ureters. Receiver-operating characteristic analysis of renal pelvic diameter as a diagnostic test for ureteral obstruction found an area under the curve not significantly different from 0.5. There was good agreement between results of radiography and ultrasonography for presence of urinary calculi (kappa 0.67). Treatment was medical in 171 (72%) cats and surgical (ureteral stent or bypass device) in 67 (28%). Death in hospital was significantly associated with serum creatinine and presence of peritoneal fluid, but not with clinical diagnosis, ultrasonographic signs or treatment method. Conclusions and relevance Ultrasonography may be used to identify azotaemic cats at greatest risk of ureteral obstruction, but when using pyelography as the reference test ultrasonography appears to be inaccurate for diagnosis of ureteral obstruction.

Objectives The objective of this study was to identify the renal ultrasonographic (US) findings most strongly associated with azotaemia in cats. Methods US findings in 238 cats with (serum creatinine >180 μmol/l) and 270 cats without azotaemia were compared in a retrospective case-control study. Cats with pre-renal azotaemia or urethral obstruction were excluded. Data extracted from the medical records included age, body weight and body condition score (BCS). Quantitative and subjective US findings were extracted from archived ultrasound images and contemporaneous reports. Results In non-azotaemic cats, mean ± SD renal length was 40.1 ± 5.5 mm. Male cats had larger kidneys than female cats (mean difference 5.2 mm; P = 0.001) and, on average, the right kidney was slightly larger than the left (mean difference 1.6 mm; P = 0.01). Azotaemic cats had significantly lower mean body weight and BCS, and greater mean age and renal pelvic diameter. Renal pelvic diameter was negatively correlated with urine specific gravity (ρ -0.44, P <0.001). Compared with non-azotaemic cats, there was no difference in mean renal length of azotaemic cats because the numbers with enlarged kidneys and small kidneys were similar. Radiologists' subjective assessments of renal size differed markedly between azotaemic and non-azotaemic cats, with azotaemic cats more likely to be recorded falsely as having abnormally small or enlarged kidneys. US findings significantly associated with azotaemia were perinephric fluid (odds ratio [OR] 26.4, 95% confidence interval [CI] 3.4-207.7), small kidneys (OR 8.4, 95% CI 4.0-17.4), hyperechoic renal cortex (OR 4.1, 95% CI 2.2-7.6), loss of corticomedullary differentiation (OR 4.1, 95% CI 1.8-9.6), renal calculi (OR 2.7, 95% CI 1.4-4.9), enlarged kidneys (OR 2.5, 95% CI 1.2-5.5) and dilated renal pelvis (OR 1.6, 95% CI 1.3-1.9). Conclusions and relevance Perinephric fluid was the US finding most strongly associated with azotaemia in this study and may merit more emphasis than it has received to date. Bias in radiologists' subjective assessments of renal size suggests that other subjective findings will also be biased.