Abstract Background Urolithiasis in small ruminants has a poor long-term prognosis, and long-term clinical outcomes are variable and unpredictable. Objectives To assess the accuracy of preoperative and postoperative blood l-lactate concentrations in predicting a negative outcome in goats undergoing tube cystostomy. Animals Thirty-four male goats undergoing tube cystostomy. Methods Retrospective study. Medical records of goats undergoing tube cystostomy from 2015 to 2020 were reviewed. Clinical variables recorded included signalment, procedures before surgery, urolith location and type, duration of hospitalization, and heart rate. PCV, plasma total protein, potassium, preoperative and postoperative blood l-lactate concentrations, preoperative and postoperative creatinine concentrations, and relative changes in blood l-lactate and creatinine concentrations over time were measured using heparinized blood. A negative outcome was defined as death or euthanasia from urolithiasis complications at 6 months after discharge. Negative outcomes as a function of independent clinical variables were evaluated using χ2 or Fisher's exact tests, and multivariate logistic regression. P < .05 was considered significant. Results Median (95% confidence interval) preoperative, postoperative, and the relative change over time of blood l-lactate concentrations were 3.3 mmol/L (2.2, 4.8), 1.0 mmol/L (0.7, 1.3), and 0.4 mmol/L (−3.5, 3.2), respectively. Preoperative (P = 1), postoperative (P = .14), and the relative change over time (P = .63) of blood l-lactate concentrations were not significant predictors of a negative outcome. Furthermore, all other clinical variables measured were not significant predictors of a negative outcome (P > .05). Conclusions and Clinical Importance Veterinarians should advise clients that clinical outcomes after tube cystostomy in goats are likely unpredictable.