Comparison of regular insulin infusion doses in critically ill diabetic cats: 29 cases (1999–2007)

Objective – To compare biochemical parameters, neurologic changes, length of hospital stay, and clinical improvement in 3 groups of cats with diabetic ketosis/diabetic ketoacidosis (DK/DKA) prescribed varied doses of regular insulin as a continuous rate of infusion (CRI). Design – Retrospective study. Setting – University teaching hospital. Animals – Twenty‐nine client‐owned cats with DK/DKA prescribed a regular insulin CRI. Interventions – Cats were grouped as follows: 7 cats each in Group 1 and 2, (prescribed 1.1 and 2.2 U/kg/d, respectively), and 15 cats in Group 3 (prescribed increasing doses as needed). Measurements and Main Results – None of the groups received the total prescribed dose of insulin. The mean actual dose administered/kg/d ranged from 0.30 (0.21) to 0.87 (0.32) U/kg/d in Groups 1, 2, and 3. There was no difference in mean minimum blood glucose (BG) per 4 hours or change in BG from baseline per 4 hours between Groups 1 and 2 (P=0.63, 0.50). There was no difference between groups regarding the time required to reach a BG ≤13.9 mmol/L (250 mg/dL), serum phosphorus or potassium concentrations relative to baseline values (P=0.53, 0.90), length of time until urine or serum ketones were no longer detected (P=0.73), the animal commenced eating (P=0.24), or length of hospital stay (P=0.63). Four of the cats had declining mentation during hospitalization; there were no relationships between osmolality at presentation, either prescribed or administered insulin dose, and mentation changes. Three of the 4 cats with declining mentation survived. Twenty‐seven of the 29 cats (93%) survived to discharge. Conclusions – In this study, prescribing the published canine dose (2.2 U/kg/d) of regular insulin to cats with DK/DKA does not appear to increase the frequency of adverse neurologic or biochemical sequelae compared with cats that are prescribed the published cat dose (1.1 U/kg/d). The use of a sliding scale for determination of infusion rates significantly reduces the amount of insulin cats receive in this setting. Determination of whether adverse sequelae would occur more frequently if cats with DK/DKA received the full insulin prescribed doses of 1.1, 2.2, or >2.2 U/kg/d is warranted. Further controlled studies are necessary to determine if higher doses of insulin are associated with beneficial effects on morbidity or mortality.     

Retrospective Study: Surgical intervention in the management of severe acute pancreatitis in cats: 8 cases (2003–2007)

Objective – To evaluate clinical characteristics and outcomes of cats undergoing surgical intervention in the course of treatment for severe acute pancreatitis. Design – Retrospective observational study from 2003 to 2007 with a median follow‐up period of 2.2 years (range 11 d–5.4 y) postoperatively. Setting – Private referral veterinary center. Animals – Eight cats. Interventions – None. Measurements and Main Results – Quantitative data included preoperative physical and clinicopathologic values. Qualitative parameters included preoperative ultrasonographic interpretation, perioperative and intraoperative feeding tube placement, presence of free abdominal fluid, intraoperative closed suction abdominal drain placement, postoperative complications, microbiological culture, and histopathology. Common presenting clinical signs included lethargy, anorexia, and vomiting. Leukocytosis and hyponatremia were present in 5 of 8 cats. Hypokalemia, increased total bilirubin, and hyperglycemia were present in 6 of 8 cats. Elevated alanine aminotransferase and aspartate transferase were present in all cats. Surgery for extrahepatic biliary obstruction was performed in 6 cats, pancreatic abscess in 3 cats, and pancreatic necrosis in 1 cat. Six of the 8 cats survived. Five of the 6 cats that underwent surgery for extrahepatic biliary obstruction and 1 cat that underwent pancreatic necrosectomy survived. All 5 of the cats with extrahepatic biliary obstruction secondary to pancreatitis survived. The 2 nonsurvivors included a cat with a pancreatic abscess and a cat with severe pancreatitis and extrahepatic biliary obstruction secondary to a mass at the gastroduodenal junction. Postoperative complications included progression of diabetes mellitus, septic peritonitis, local gastrostomy tube stoma inflammation, local gastrostomy tube stoma infection, and mild dermal suture reaction. Conclusion – Cats with severe acute pancreatitis and concomitant extrahepatic biliary obstruction, pancreatic necrosis, or pancreatic abscesses may benefit from surgical intervention. Cats with extrahepatic biliary obstruction secondary to severe acute pancreatitis may have a good prognosis.     

Retrospective Study: The association of blood lactate concentration with outcome in dogs with idiopathic immune‐mediated hemolytic anemia: 173 cases (2003–2006)

Objective – To determine the association of blood lactate with outcome and response to transfusion therapy in dogs with idiopathic immune‐mediated hemolytic anemia (IMHA). Design – Retrospective study. Setting – Urban veterinary small animal emergency hospital. Animals – One hundred and seventy‐three client‐owned dogs with IMHA. Interventions – None. Measurements and Main Results – Serial blood lactate concentration, therapeutic interventions, and outcome were recorded. Nonsurvivors were defined as those that died or were euthanized. One hundred and thirty‐three dogs (77%) survived, 35 (20%) were euthanized, and 5 (3%) died. One hundred forty‐five dogs (84%; 145/173) had a lactate concentration above the laboratory reference interval [0.46–2.31 mmol/L] on presentation. Blood lactate at presentation was higher in the nonsurvivors (median 4.8 mmol/L; 0.5–13.6) compared with survivors (median 2.9 mmol/L; 0.3–13.2) (P<0.01). All dogs presenting with hyperlactatemia that normalized (<2.0 mmol/L) within 6 hours of admission survived, whereas, 71% of dogs that had a persistent hyperlactatemia at 6 hours survived (P=0.034). Lactate was positively correlated with age, BUN, and alkaline phosphatase, and inversely correlated with PCV. Receiver operating curve analysis for lactate concentration at admission as a test for outcome had an area under the curve of 0.69 with an optimal lactate cutoff concentration of 4.4 mmol/L correctly predicting outcome 73% of the time (sensitivity 60%, specificity 77%). Conclusions – Lactate concentration at presentation was significantly higher in nonsurvivors than survivors. Lactate was significantly correlated with previously reported outcome variables but lactate concentration at admission, as a predictor for outcome was less than optimal. However, serial lactate concentration measurements may be more predictive as patients with persistent hyperlactatemia 6 hours after admission were less likely to survive. Prospective studies evaluating serial lactate concentration while controlling for other variables may provide further insight into lactate measurement as a prognostic indicator in animals with IMHA.     

Retrospective evaluation of postoperative nasotracheal tubes for oxygen supplementation in dogs following surgery for brachycephalic syndrome: 36 cases (2003–2007)

Objective – To assess the utility of nasotracheal tubes in postoperative oxygen supplementation in dogs following corrective surgery for brachycephalic syndrome. Design – Retrospective study 2003–2007. Setting – University teaching hospital. Animals – Thirty‐six client‐owned dogs that underwent corrective surgery for brachycephalic syndrome. Interventions – None. Measurements and Main Results – Medical records were reviewed for animals that underwent surgical interventions for brachycephalic syndrome including palatoplasty, ventriculectomy, and rhinoplasty. Data collected included signalment, presenting complaints, analgesic and surgical interventions, type of supplemental oxygen therapy, complications and mortality occurring during hospitalization. A nasotracheal tube (NTT) was placed in 20 dogs at the end of surgery; 16 dogs received other forms of oxygen supplementation (8) or no oxygen supplementation (8) during recovery. The total number of postoperative complications was similar in both groups (8/20 dogs with NTTs and 7/16 in those without NTTs). However, respiratory distress was observed in 5 dogs without NTTs but was not observed in any dog while an NTT was in place. One dog in each group died postoperatively. Conclusion – Placement of an NTT was found to be easy and may offer benefit in dogs with brachycephalic syndrome as a noninvasive means of delivering oxygen. The use of NTT may minimize severe postoperative morbidity, in particular by reducing postoperative respiratory distress.     

Evaluation of acute congestive heart failure in dogs and cats: 145 cases (2007–2008)

Objective – To characterize the clinical presentation, management, and in‐hospital outcomes of dogs and cats diagnosed with acute congestive heart failure (CHF). Design – Retrospective study of animals seen between January 2007 and May 2008. Setting – Emergency service at a university teaching hospital. Animals – Ninety dogs and 55 cats with CHF. Measurements and Main Results – Patient characteristics, including age, clinical signs, clinicopathologic abnormalities, diagnostic testing, and outcome were recorded. Forty‐eight of the animals already were receiving cardiac medications at the time of presentation. The most common diseases represented were chronic valvular disease and cardiomyopathies. Cats had significantly lower median body temperature at admission compared with dogs (P<0.001). The most common abnormalities were elevated lactate (64%), elevated BUN (52%), hypochloremia (31%), hyperglycemia (27%), and elevated liver enzymes (26%). Many of these became even more prevalent during hospitalization. One hundred and sixteen animals were discharged from the hospital, for a survival rate of 80%. There was no survival difference between dogs and cats (P=0.39). Dogs that developed hypokalemia during hospital stay (P=0.04) were more likely to survive compared with those without hypokalemia and initial body temperature was lower for those cats that did not survive (P=0.02). Of those that did not survive, the majority were euthanized (n=25), while 4 dogs died. Conclusions – Dogs and cats presented to the emergency service with CHF had a high survival rate. In cats, initial body temperature was lower for those cats that did not survive. Although clinicopathologic abnormalities were common in both species, only dogs with hypokalemia had improved survival to hospital discharge.