Plasma lactate concentrations in septic peritonitis: A retrospective study of 83 dogs (2007-2012)

Diagnosis of Septic Body Cavity Effusion in Dogs and Cats: Cytology vs. Bacterial Culture

The elective test for the determination of the effusions etiopathogenesis is represented by physico-chemical analysis and cytology. Nevertheless, the bacterial culture and antibiotic sensitivity tests are crucial for setting therapy and for the outcome. This study compared cytology with microbiology in the etiologic diagnosis of exudative body cavity effusions in dogs and cats collected from October 2018 to October 2022. All samples underwent aerobic and anaerobic culture and cytology examination. Bacterial identifications were confirmed using matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, whereas cytological samples were blindly evaluated either in May Grunwald-Giemsa (MGG) or Gram-stained samples by two board-certified clinical pathologists. A moderate agreement (κ = 0.454) between cytology and bacterial culture was revealed. The sensitivity of the cytological evaluation in our study ranged from 38.5% to 67.9%, and the specificity ranged from 88.9% to 100%, depending on the type of the effusion, so cytology may not be representative of the etiopathogenesis, whereas bacterial culture can misidentify or fail to isolate the correct pathogen for difficult in vitro growing due to the presence of inhibitory substances or contamination. Cytology and bacterial culture results for exudative body cavity effusions in dogs and cats can be misleading if conducted separately, so these two tests should be performed together to increase diagnostic accuracy.

Performance evaluation of a Test&Treat rapid detection kit for the diagnosis of septic effusions in dogs and cats

OBJECTIVE

To evaluate the sensitivity and specificity of a veterinary point-of-care (POC) luminometer-based kit for the diagnosis of septic peritoneal or pleural effusion in dogs and cats.

DESIGN

Prospective study performed between January 2020 and July 2021.

SETTING

University teaching hospital.

ANIMALS

Forty-eight animals with naturally occurring peritoneal or pleural effusion collected by aseptic abdominocentesis or thoracocentesis.

PROCEDURES

Effusion samples were split into filtered (using a 10-micron filter) and unfiltered aliquots and analyzed by the POC instrument according to the manufacturer's instructions and following variable incubation periods. Samples were also plated aerobically on standard and blood agar plates. Proprietary reagents were added to samples, causing bacterial ATP to generate bioluminescence that is detected by the luminometer. Bioluminescence values (relative light units [RLUs]) were recorded and compared with the presence of bacterial growth on the culture plates. Nucleated cell counts in native and filtered effusion samples were recorded.

RESULTS

Twenty-one samples were septic based on positive culture. RLUs were higher in septic effusions for filtered and native effusions compared with sterile effusions. The use of a filter reduced cell counts. In filtered samples incubated for 30 minutes before testing, the sensitivity and specificity of the luminometer for diagnosis of infection in cavitary effusions were 81% and 82%, respectively, using a cutoff of 12,202 RLUs.

CONCLUSIONS

The luminometer kit evaluated in this study represents a viable screening tool for diagnosis of septic cavitary effusions and could be used in conjunction with other POC diagnostics to support the rapid diagnosis of infection.

Comparison of two point of care lactate instruments in guinea pigs (Cavia porcellus)

Background

Lactate measurements have been utilized as diagnostic and prognostic tools for a variety of veterinary species. Reference intervals for lactate have not been published or validated in guinea pigs.

Methods

Whole blood from 48 anesthetized laboratory guinea pigs (46 Dunkin Hartley [38 males, eight females]; two Strain 13 [two males]) was analyzed using two point of care instruments (iSTAT and Lactate Plus). There were two consecutive timepoints on the iSTAT (iSTAT time 1 and time 2) and three consecutive timepoints on the Lactate Plus (Lactate Plus time 1, time 2, and time 3).

Results

There was agreement with no constant or proportional bias between the two instruments compared at equivalent timepoints (iSTAT time 1 and Lactate Plus time 3) as determined by Bland-Altman (bias: -0.19; 95% LoA: -0.55 to 0.16) and Deming linear regression analyses (slope: 1.092, 95% confidence intervals (CI): -0.9 to 1.29; y-intercept: 0.09, 95% CI: -0.12 to 0.30). Reference intervals for iSTAT time 1 were 0.49 to 1.83 mmol/L and Lactate Plus time 1 were 0.60 to. 2.2 mmol/L. There was a significant increase in lactate values from iSTAT time 1 to iSTAT time 2 and from Lactate Plus time 1 to Lactate Plus time 3.

Conclusions and Clinical Relevance

This study found strong agreement between the point of care instruments. Reference intervals for lactate for both the iSTAT and Lactate Plus instruments were similar to canine and feline intervals. Analysis should occur within 5 minutes of sample collection. Future work should assess lactate as a prognostic indicator in guinea pigs.

Aetiology, clinical parameters and outcome in 113 dogs surgically treated for septic peritonitis (2004-2020)

BACKGROUND

Septic peritonitis (SP) is a common life-threatening condition. The aims of this study were to describe the aetiology, clinicopathological abnormalities, complications, treatment, outcome and prognosis of dogs with SP.

METHODS

Records of 113 dogs diagnosed and surgically treated for SP between 2004 and 2020 were reviewed.

RESULTS

Overall survival rate was 74.3%. Parameters at presentation that were significantly associated with mortality were lateral recumbency (p = 0.001) and elevated respiratory rate (p = 0.045). Hypotension during or after surgery (p < 0.001), liver injury (p < 0.001) and acute kidney injury (p < 0.001) were also more common in non-survivors. The source of contamination, number of surgeries or the location of perforation in cases of gastrointestinal tract perforation were not associated with mortality. Delta glucose (serum vs. abdominal) was available in 36 out of 113 dogs and the difference was more than 20 mg/dl in only 22 of out 36 (61.1%) cases.

CONCLUSION

Liver and kidney injuries play a role in mortality, and early diagnosis and intervention are recommended to prevent multiple organ dysfunction and death. The reported high sensitivity of delta glucose is questionable in diagnosis of SP.

Association of point-of-care blood variables obtained from dogs and cats during cardiopulmonary resuscitation and following return of spontaneous circulation with patient outcomes

OBJECTIVE

To investigate the association of point-of-care biochemical variables obtained during CPR or within 24 hours of return of spontaneous circulation (ROSC) with patient outcomes.

DESIGN

Retrospective study.

SETTING

University teaching hospital.

ANIMALS

Ninety-four dogs and 27 cats undergoing CPR according to the Reassessment Campaign on Veterinary Resuscitation guidelines.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Blood gas, acid-base, electrolyte, glucose, and plasma lactate values obtained during CPR or within 24 hours of ROSC were retrospectively evaluated and are described. The blood sample type and collection time with respect to CPR initiation and ROSC were recorded. Measured variables, collection times, and species were included in a multivariable logistic regression model to estimate the odds ratio (OR) and 95% confidence interval of ROSC, sustained ROSC (≥20 min), and survival to hospital discharge. Significance was set at P < 0.05. Seventy-two venous blood samples obtained during CPR and 45 first venous and arterial blood samples obtained after ROSC were included in logistic regression analysis. During CPR, PvO₂ (1.09 [1.036-1.148], P = 0.001) and venous standard base excess (SBE) (1.207 [1.094-1.331], P < 0.001) were associated with ROSC. PvO₂ (1.075 [1.028-1.124], P = 0.002), SBE (1.171 [1.013-1.353], P = 0.032), and potassium concentration (0.635 [0.426-0.946], P = 0.026) were associated with sustained ROSC. Potassium concentration (0.235 [0.083-0.667], P = 0.007) was associated with survival to hospital discharge. Following ROSC, pH (69.110 [4.393-1087], P = 0.003), potassium concentration (0.222 [0.071-0.700], P = 0.010), and chloride concentration (0.805 [0.694-0.933], P = 0.004) were associated with survival to hospital discharge.

CONCLUSIONS

Biochemical variables such as PvO₂ , SBE, and potassium concentration during CPR and pH, potassium, and chloride concentration in the postarrest period may help identify dogs and cats with lower odds for ROSC or survival to hospital discharge following CPR.

Association of the origin of contamination and species of microorganisms with short-term survival in dogs with septic peritonitis

OBJECTIVE

To assess the association between anatomical location of contamination and mortality in dogs with gastrointestinal and biliary origin of septic peritonitis.

METHODS

Medical records at two private referral hospitals between 2003 and 2020 were retrospectively reviewed. Cases were included if the origin of contamination was confirmed intraoperatively within the gastrointestinal or biliary tract. Cases were excluded if the dog died or was euthanized intraoperatively or where the data regarding the origin of contamination were not available. The association of anatomical origin with survival was assessed specifying the locations as stomach, small intestine, large intestine and biliary tract. The gastrointestinal tract origin was further subdivided into pylorus, nonpylorus, duodenum, jejunum, ileum, caecum and colon.

RESULTS

The overall survival rate was 75.9% (n = 44/58). There were no significant differences in survival among different anatomical origins of contaminations before or after subdivision (P = 0.349 and 0.832, respectively). Also, there was no association between isolated microorganism species in microbiological culture and the anatomical origin (P = 0.951) and the microorganism species was not associated with survival (P = 0.674).

CONCLUSIONS

There was no association between anatomical location of leakage, microorganism species and survival although further studies are warranted to analyse the relationships between anatomical leakage site and microorganism species as well as microorganism species and mortality.

Evaluation of cardiac troponin I as a predictor of death in critically ill cats

BACKGROUND

Abnormally high serum cardiac troponin I (cTnI) concentration, reflecting leakage from or necrosis of cardiomyocytes, is a negative prognosticator for death in dogs.

OBJECTIVES

To investigate in critically ill cats whether serum cTnI concentration is abnormally high, identify conditions associated with abnormally high cTnI concentrations, and evaluate cTnI as an independent prognosticator for death and a potential coprognosticator to the acute patient physiologic and laboratory evaluation (APPLE) score in cats.

ANIMALS

One hundred nineteen cats admitted to intensive care units (ICU) and 13 healthy cats at 2 university teaching hospitals.

METHODS

Prospective study. Clinical examinations were performed, APPLE scores calculated, and serum cTnI and serum amyloid A (SAA) measured within 24 hours after admission. Outcome was defined as death/euthanasia or survival to discharge, 28 and 90 days after ICU-admission. Prognostic capacity of cTnI, APPLE scores and models combining cTnI and scores were evaluated by receiver-operator-characteristic analyses.

RESULTS

Median (IQR) serum cTnI concentration was higher in ill (0.63 [0.18-2.65] ng/mL) compared to healthy (0.015 [0.005-0.041] ng/mL) cats (P < .001) and higher in subgroups with structural cardiac disease (2.05 [0.54-16.59] ng/mL; P < .001) or SAA >5 mg/L (0.84 [0.23-2.81] ng/mL; P = .009) than in cats without these characteristics (0.45 [0.12-1.70] and 0.35 [0.015-0.96] ng/mL). The in-hospital case fatality rate was 29%. Neither serum cTnI concentration for all critically ill cats (area-under-the-curve 0.567 [95% CI 0.454-0.680], n = 119) or subgroups (0.625 [0.387-0.863], n = 27; 0.506 [0.360-0.652], n = 86), nor APPLE scores (fast 0.568 [0.453-0.682], full 0.585 [0.470-0.699], n = 100), were significant prognosticators for death.

CONCLUSIONS AND CLINICAL IMPORTANCE

Abnormally high serum cTnI concentration was common in critically ill cats. Unlike in dogs, cTnI did not confer prognostic information regarding death.

Evaluation of Resting Serum Bile Acid Concentrations in Dogs with Sepsis

Recent studies in the human literature suggest that serum bile acid concentrations could be an early predictor of short-term survival in critically ill patients. However, there is no available information in the veterinary literature regarding serum bile acid concentrations in dogs with sepsis. We aimed to evaluate if resting serum bile acid concentrations differ between septic and non-septic dogs. This was a retrospective observational study, of medical records at a single referral center over a twelve-year period. Twenty-six client-owned dogs diagnosed with sepsis were identified. Twenty-one dogs presenting with a non-hepatobiliary systemic disease and twenty-nine dogs admitted for an elective orthopedic procedure, considered otherwise healthy, were selected as control groups. Resting serum bile acid concentrations were significantly higher in the septic compared to the non-septic groups (ill control and orthopedic control groups). However, when assessing bile acid concentrations between groups individually, no difference was identified between the septic and the orthopedic control group. These results should be interpreted cautiously.

Prognostic value of lactate in cats presented in respiratory distress to the emergency room

Studies demonstrating the prognostic utility of plasma lactate concentration and lactate clearance in cats are limited. The objective of this study was to determine the prognostic utility of plasma lactate concentration upon admission and plasma lactate clearance in cats presented to the emergency room with respiratory distress attributed to underlying cardiac or respiratory disease. Additionally, we sought to determine if plasma lactate concentration on admission was significantly associated with the underlying cause of respiratory distress (cardiac vs. respiratory), type of respiratory disease, and vital parameters. Seventy-one cats presented in respiratory distress to the ER at a university teaching hospital were enrolled in this retrospective study. Admission lactate concentration was not associated with survival, duration of hospitalization, vital parameters, or underlying etiology for respiratory distress. In contrast, lactate clearance was significantly associated with survival and length of hospitalization. While a statistically significant association between lactate clearance and length of hospitalization was identified, this finding lacked clinical significance where an increase in lactate concentration by 1% was associated with an increased length of hospitalization by 11.4 min (p = 0.035). Results of this study suggest that lactate clearance may have prognostic utility in this population of cats. Further studies including the larger population of cats with underlying cardiac or respiratory disease are warranted.

Primary repair of nonsteroidal anti-inflammatory drug-associated full thickness gastrointestinal ulcers in 11 dogs

OBJECTIVE

To report the outcomes of dogs that underwent primary repair of gastroduodenal perforations associated with the administration of nonsteroidal anti-inflammatory drugs (NSAID). A secondary objective was to identify clinicopathological findings that predisposed dogs to postoperative death.

STUDY DESIGN

Retrospective study.

ANIMALS

Eleven dogs with complete gastric or duodenal perforation related to administration of an NSAID that underwent primary surgical repair.

METHODS

Medical records were reviewed for dogs that presented with peritonitis due to a complete gastroduodenal perforation while receiving NSAIDs between November, 2011 and January, 2021. Data collected included patient characteristics, clinical signs, clinicopathological results, surgical details, and postoperative management and outcome.

RESULTS

All dogs were large breeds (mean weight 42 kg; range 22-75 kg), with a mean age of 7.35 years. Nine dogs from a total of 11 (82 %) received a concurrent corticosteroid and NSAID, or a higher dose/frequency/length of NSAID administration than recommended by the manufacturer. All gastroduodenal perforations were found in the upper gastrointestinal tract. Eight of 11 (73%) dogs survived to discharge. The median postoperative duration of follow up was 444 days (range 2-1460 days). No association was detected between ulcer size or location and mortality.

CONCLUSION

Most dogs who underwent primary repair of complete gastroduodenal ulcers survived. Gastroduodenal perforations were generally due to the administration of higher or longer doses of NSAIDs, or concurrent administration of another NSAID or corticosteroid.

CLINICAL SIGNIFICANCE

Primary closure may be associated with a high success rate in dogs with full thickness gastroduodenal ulcers.

The Effect of Different Opioids on Acid-Base Balance and Blood Gas Analysis in Hospitalized Dogs

Pain management is central to veterinary practice, contributing to successful case outcomes and enhancement of the veterinarian-client-patient relationship. Analgesic drugs represent one of the pillars of the multimodal approach to acute and chronic pain management. In dogs, the most used opioids are methadone, buprenorphine and tramadol. Several episodes of hypoglycemia in people treated with tramadol and methadone have recently been described. The aim of this work is to evaluate the changes in the glycemic and acid-base balance induced by tramadol, methadone and buprenorphine in hospitalized dogs. A retrospective review of the medical records of dogs hospitalized for both medical and surgical reasons was performed. During 2018-2020, a total of 876 canine patients were treated with opioids, including 228 with tramadol, 273 with methadone and 375 with buprenorphine. Of all these dogs, only a small percentage met the inclusion criteria presented in the initial design. All the hospitalized animals were monitored daily through clinical examination and blood sampling. Blood samples were obtained before opioid administration (T0), and 24 h (T1) and 48 h (T2) after °pioid administration. The following parameters were evaluated: blood gas value (pH, pCO₂), acid-base state (cHCO₃), oxymetric values (ctHb, haematocrit), electrolyte values (K+, Na+, iCa, Cl-) and metabolic values (glucose, lactate, anion GAP K+c). The glycemic value in enrolled dogs showed a decrease over time, regardless of the type of opioid used, but remained within the physiological range. The highest average glycemic drop was recorded for methadone, between T0 and T1, followed by tramadol between T1 and T2, while buprenorphine recorded the highest overall glycemic drop between T0-T2 when compared to the other two opioids. Female dogs showed the greatest drop in glycemic value. Lactate concentration always presented values beyond the physiological range at an early stage, which then normalized quickly. Measurement of electrolyte concentrations showed a consistent increase in the values of iCa, Na and Cl. In hospitalized dogs treated with opioids monitoring of gas analytic parameters is important and more attention should be paid to patients hospitalized with certain metabolic and endocrine diseases.

Red cell distribution width, illness severity, and all-cause mortality in dogs admitted to the ICU

OBJECTIVE

To determine whether red cell distribution width (RDW) can predict illness severity and mortality risk in a heterogenous population of dogs admitted to the ICU.

DESIGN

Prospective observational study.

SETTING

Large, urban, private teaching hospital.

ANIMALS

One hundred eleven dogs consecutively admitted to the ICU between September 2017 and December 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Abbreviated Acute Patient Physiologic and Laboratory Evaluation (APPLE_fast ) score and RDW were measured within 6 h of ICU admission. This study did not demonstrate a significant difference in illness severity across patients stratified by RDW. There was no difference in RDW between survivors and nonsurvivors at hospital discharge or at 30 days.

CONCLUSIONS

In this study population, RDW did not correspond with illness severity as measured by APPLE_fast . Moreover, RDW did not predict in-hospital or 30-day mortality.

Classification of Septic Shock Phenotypes Based on the Presence of Hypotension and Hyperlactatemia in Cats

Background: Three different phenotypes of septic shock based on changes in blood pressure and lactate are recognized in people. Dysoxic shock, representing the combination of fluid-refractory hypotension and hyperlactatemia, is characterized by greater disease severity and mortality compared to cryptic shock (hyperlactatemia alone) and vasoplegic shock (hypotension with normal blood lactate). Little is known about septic shock and specifically its phenotypes in cats. Objective: To analyze the characteristics and prognostic implications of three septic shock phenotypes in cats with sepsis. Methods: Cats with septic shock were prospectively included. Septic shock was defined by the presence of hypotension (mean blood pressure <60 mmHg) requiring vasopressor support and/or persistent hyperlactatemia (>4 mmol/L) and classified in three subgroups: dysoxic shock, vasoplegic shock and cryptic shock. Clinical and clinicopathological variables including APPLE_fast and APPLE_full scores, occurrence of multi-organ dysfunction syndrome (MODS; presence of at least two dysfunctional organs simultaneously) and outcome were compared among subgroups. Cats with sepsis showing normal blood pressure and lactate concentrations hospitalized during the study period were included as uncomplicated sepsis, and compared to cats with septic shock for selected variables. Length of hospital stay and mortality were evaluated in the whole study population. Odds ratios for mortality were calculated using logistic regression analysis. Significance was set at P < 0.05. Results: The study enrolled 48 cats with uncomplicated sepsis and 37 cats with septic shock (dysoxic shock n = 17; vasoplegic shock n = 11; cryptic shock n = 7). Cats with dysoxic shock had significantly higher APPLE_fast and APPLE_full scores compared to vasoplegic and cryptic shock. Mortality rates were not significantly different among cryptic (57%), dysoxic (65%) and vasoplegic shock (91%), while MODS occurrence was significantly lower in cats with cryptic shock (57%) compared to patients affected by dysoxic (94%) and vasoplegic (100%) shock. Cats with septic shock had higher frequency of MODS and greater mortality rate than cats with uncomplicated sepsis. Conclusion: Despite similar in-hospital mortality, cats with dysoxic and vasoplegic shock are characterized by having higher occurrence of multi- organ dysfunction compared to cats affected by cryptic shock. Results from this study suggest novel means of identifying high-risk subgroups of septic cats.

Perioperative Outcome in Dogs Undergoing Emergency Abdominal Surgery: A Retrospective Study on 82 Cases (2018-2020)

Emergency abdominal surgery carries high morbidity and mortality rates in human medicine; however, there is less evidence characterising the outcome of these surgeries as a single group in dogs. The aim of the study was to characterise the clinical course, associated complications and outcome of dogs undergoing emergency abdominal surgery. A retrospective study was conducted. Dogs undergoing emergency laparotomy were included in the study. Logistic regression analysis was performed to identify variables correlated with death and complications. Eighty-two dogs were included in the study. The most common reason for surgery was a gastrointestinal foreign body. Overall, the 15-day mortality rate was 20.7% (17/82). The median (range) length of hospitalisation was 3 (0.5-15) days. Of the 82 patients, 24 (29.3%) developed major complications and 66 (80.5%) developed minor complications. Perioperative factors significantly associated with death included tachycardia (p < 0.001), hypothermia (p < 0.001), lactate acidosis (p < 0.001), shock index > 1 (p < 0.001), leukopenia (p < 0.001) and thrombocytopenia (p < 0.001) at admission, as well as intraoperative hypotension (p < 0.001) and perioperative use of blood products (p < 0.001). The results of this study suggest that mortality and morbidity rates after emergency abdominal surgery in dogs are high.

A feasibility study investigating the utility of a point-of-care rapid immunoassay for detecting septic peritoneal effusion in dogs

OBJECTIVE

To determine the sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy of a point-of-care urine bacterial rapid immunoassay (RIA) for a diagnosis of septic peritonitis, compared to more traditional diagnostic tools, such as cytology and bacterial culture.

DESIGN

Prospective, cross-sectional feasibility study conducted from October 2016 to June 2017.

SETTING

Four locations within a private practice referral hospital.

ANIMALS

Sixty-four dogs with peritoneal effusion of any etiology were enrolled. Four dogs were excluded due to absent RIA or bacterial culture results. Two additional dogs were excluded because of an inability to definitively classify them as having septic peritonitis.

INTERVENTIONS

Abdominocentesis was performed to obtain peritoneal effusion samples for aerobic and anaerobic bacterial culture, cytology, and RIA. Cytological slides were evaluated by a clinical pathologist following enrollment.

MEASUREMENTS AND MAIN RESULTS

Fifty-eight dogs were included in the study, 8 of which were classified as having septic peritonitis. Compared to final diagnosis of septic peritonitis, RIA had a low PPV (36.8%) but good NPV (97.4%) and was 77.5% accurate. SN of RIA (87.5%) to diagnose septic peritonitis was similar to cytology (85.7%) and bacterial culture (87.5%); however, SP was lower (76%, 100%, and 98%, respectively). Cytology had the best overall predictive values and accuracy for diagnosing septic peritonitis (PPV 100%, NPV 97.9%, and accuracy 98%) compared to RIA and bacterial culture.

CONCLUSIONS

RIA testing was similarly sensitive in identifying septic peritonitis compared to cytology and bacterial culture but was not very specific or accurate. As a stand-alone test, RIA commonly had false-positive test results, making it unreliable in identifying septic peritonitis. Cytology was the most accurate diagnostic test and had no false-positive results. Further investigation with a larger sample size and prevalence of septic peritonitis may prove beneficial.

Retrospective evaluation of the prognostic utility of quick sequential organ failure assessment scores in dogs with surgically treated sepsis (2011-2018): 204 cases

OBJECTIVE

To assess the prognostic utility of admission quick Sequential Organ Failure Assessment (qSOFA) scores for in-hospital mortality in a population of dogs with surgically treated sepsis.

DESIGN

Retrospective cohort study of dogs from January 2011 to January 2018.

SETTING

University teaching hospital.

ANIMALS

One thousand three hundred nine cases were identified with a clinical diagnosis of sepsis requiring surgical source control. Two hundred and four dogs with surgically treated sepsis met inclusion criteria, defined as: meeting 2 or more systemic inflammatory response syndrome (SIRS) criteria with a documented source of infection. One hundred and forty-three cases of septic peritonitis, 26 cases of septic soft tissue infection, 20 cases of pyometra, and 15 cases of pyothorax were evaluated.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Overall in-hospital mortality was 63 of 204 (30.9%). Patients with a qSOFA ≥ 2 were more likely to die or be euthanized (odds ratio [OR] 7.1, 95% confidence interval [CI] 2.9-16.4; P < 0.0001). Survivor and nonsurvivor qSOFA scores were significantly different in all categories. Dogs with septic peritonitis and a qSOFA ≥ 2 had an increased risk of postoperative complications (OR 3.9; 95% CI 1.3-11.1; P = 0.02). qSOFA scores were correlated with length of hospitalization in survivors of all-cause surgical sepsis (r = 0.28, P = 0.0007), septic peritonitis (r = 0.33, P = 0.001), and septic soft tissue infection (r = 0.59, P = 0.004).

CONCLUSIONS

This was the first study to retrospectively evaluate the prognostic utility of qSOFA scores in dogs surgically treated for sepsis. Dogs diagnosed with septic peritonitis and other causes of surgically treated sepsis with a qSOFA ≥ 2 may have a higher risk of in-hospital mortality, although future prospective studies are necessary.

Retrospective evaluation of the prognostic utility of plasma lactate concentration and serial lactate measurements in dogs and cats presented to the emergency room (January 2012 - December 2016): 4863 cases

OBJECTIVE

To determine the prognostic significance of plasma lactate concentration, plasma lactate clearance, and delta lactate in dogs and cats presented to an emergency room (ER).

DESIGN

Retrospective study.

SETTING

University teaching hospital.

ANIMALS

A total of 8,321 animals with a plasma lactate concentration measured with 4,863 presenting to the ER and 1,529 dogs and 444 cats having a measurement within 4 hours of admission.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Plasma lactate concentration of dogs and cats presented to a university teaching hospital was retrospectively evaluated. Of dogs and cats with a plasma lactate concentration measured within 4 hours of admission to the ER, hyperlactatemia was common, and the prevalence of hyperlactatemia for dogs 78% (361/462) and cats 67% (78/116) was highest when evaluated within the first 30 minutes following admission. The distribution of patient's plasma lactate concentration was significantly higher in non-survivors compared to survivors at all time points evaluated (P < 0.001). Both lactate clearance (P = 0.010) and delta lactate (P = 0.013) were significantly different between survivors and nonsurvivors. A delta lactate > 4.5 mmol/L was 100% (95% CI: 95 to 100%) specific for nonsurvival in patients with hyperlactatemia measured within 1 hour of admission to the ER. The most common cause of hyperlactatemia was shock in dogs (24%) and urinary tract diseases in cats (22%). Shock was associated with the highest mortality rate in both dogs (61%) and cats (77%). Hyperlactatemia was significantly associated with increased mortality for dogs with shock (P = 0.001), respiratory diseases (P = 0.022), diabetes mellitus (P = 0.018), and liver dysfunction (P = 0.006).

CONCLUSIONS

Hyperlactatemia was associated with mortality in both dogs and cats when measured at any time point in the 4 hours following admission to the ER. Serial lactate measurement may also be a valuable tool to guide clinical management decisions.

Evaluation of the quick sequential organ failure assessment score plus lactate in critically ill dogs

OBJECTIVES

To apply the quick sequential organ failure assessment (qSOFA) score to dogs admitted to a veterinary ICU, and evaluate whether the addition of lactate increased the predictive ability of the score.

MATERIALS AND METHODS

A quick sequential organ failure assessment score of 0, 1, 2, or 3 was assigned to each dog based on the following criteria: respiratory rate >22 breaths per minute, altered mentation, systolic blood pressure <100 mmHg. Lactate was added to quick sequential organ failure assessment in an LqSOFA model and assigned to each patient. Disease processes evaluated included sepsis, congestive heart failure, pneumonia and pancreatitis.

RESULTS

Two hundred and sixty-seven client-owned dogs met the inclusion criteria. There was no significant difference in quick sequential organ failure assessment score between survivors and non-survivors. The use of lactate >3, 4, and 5 mmol/L incorporated into the quick sequential organ failure assessment score (L3qSOFA, L4qSOFA, L5qSOFA) distinguished between survival and non-survival (AUC=0.62; AUC=0.64; AUC=0.62, respectively). Lactate alone distinguished between survival and non-survival (AUC=0.63). Lactate concentration was significantly lower in survivors.

CLINICAL SIGNIFICANCE

In this study, quick sequential organ failure assessment was not able to predict survival in a general population of critically ill patients. The addition of lactate to the quick sequential organ failure assessment score slightly increased the predictive ability of the score.

Comprehensive Review of Biliary Peritonitis

Biliary peritonitis is a growing concern in the canine patient and a thorough understanding of the disease will lead to better treatment outcomes. This article reviews the human and veterinary literature pertaining to biliary peritonitis including both scientific reviews and original publications. Compared to human medicine, biliary peritonitis can be difficult to diagnose preoperatively. Multiple risk factors exist increasing the likelihood of development of biliary peritonitis. Treatment recommendations center on stabilization, surgical cholecystectomy, and postoperative supportive care. Clinically, further studies on treatment and prevention in veterinary medicine are warranted.

Prospective evaluation of plasma lactate parameters for prognosticating dogs with shock

OBJECTIVE

To determine whether admission venous plasma lactate concentration, serially calculated lactate variables, or the Acute Patient Physiologic and Laboratory Evaluation (APPLE_fast ) score could discriminate hospital survivors from non-survivors in dogs presenting to the emergency department with clinical signs of shock.

DESIGN

Prospective case series performed over a 24-month period.

SETTING

Large urban private teaching hospital.

ANIMALS

Seventy-one dogs admitted to the ICU with initial peripheral venous plasma lactate concentration > 2.5 mmol/L and clinical and hemodynamic parameters consistent with shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Heart rate, systolic blood pressure, temperature, initial venous plasma lactate, and APPLE_fast score were recorded at admission. Lactate concentrations were serially recorded at predefined time points and used to calculate lactate variables, including lactime (time lactate > 2.5 mmol/L), lactate clearance ([lactate_initial - lactate_delayed ]/ lactate_initial × 100), and LAC_AREA (area under the lactate concentration versus time curve). Primary outcome was survival to discharge. Overall survival rate was 61%. Admission plasma lactate did not differ between groups (P = 0.28). Lactime was shorter in survivors vs non-survivors (P = 0.03). Lactate clearance at hours (h) 1, 4, 10, and 16 was greater in survivors vs non-survivors (P < 0.05). Final plasma lactate clearance differed between groups (P < 0.05). LAC_AREA at time intervals 1 to 4 hours, 4 to 10 hours, 10 to 16 hours, and 16 to 24 hours was larger in non-survivors vs survivors (P < 0.05). Total LAC_AREA did not differ between groups (P = 0.51). Admission APPLE_fast was not different between survivors and non-survivors (P = 0.16).

CONCLUSIONS

While neither single APPLE_fast nor admission plasma lactate concentration could discriminate between hospital survivors and non-survivors, measures of lactate clearance can prognosticate survival in dogs with shock.

Fluid Resuscitation for Refractory Hypotension

Hypotension is a common occurrence, especially in anesthetized patients and in critical patients suffering from hypovolemia due to shock and sepsis. Hypotension can also occur in normovolemic animals, anesthetized or conscious, under conditions of vasodilation or decreased cardiac function. The main consequence of hypotension is decreased organ perfusion and tissue injury/dysfunction. In the human literature there is no consensus on what is the threshold value for hypotension, and ranges from < 80 to < 100 mmHg for systolic blood pressure and from < 50 to < 70 mmHg for mean arterial blood pressure have been referenced for intraoperative hypotension. In veterinary medicine, similar values are referenced, despite marked differences in normal arterial blood pressure between species and with respect to humans. Therapeutic intervention involves fluid therapy to normalize volemia and use of sympathomimetics to enhance cardiac function and regulate peripheral vascular resistance. Despite these therapeutic measures, there is a subset of patients that are seemingly refractory and exhibit persistent hypotension. This review covers the physiological aspects that govern arterial blood pressure control and blood flow to tissues/organs, the pathophysiological mechanisms involved in hypotension and refractory hypotension, and therapeutic considerations and expectations that include proper interpretation of cardiovascular parameters, fluid recommendations and therapy rates, use of sympathomimetics and vasopressors, and newer approaches derived from the human literature.

Hypophosphatemia in Dogs With Presumptive Sepsis: A Retrospective Study (2008-2018)

Background: In humans with sepsis, hypophosphatemia is a marker of illness severity and a negative prognostic indicator. Hypophosphatemia has not been previously investigated in dogs with sepsis, however. This study aimed to estimate the prevalence of hypophosphatemia in dogs, the prevalence of presumptive sepsis in dogs with hypophosphatemia, the prevalence of hypophosphatemia in dogs with presumptive sepsis and the association between outcome and hypophosphatemia in dogs with presumptive sepsis. Methods: Electronic medical records of the Cornell University Hospital for Animals from 2008-2018 were queried to identify all dogs with hypophosphatemia and all dogs with presumptive sepsis. Hypophosphatemia was defined as a serum phosphate concentration <2.7 mg/dL. Sepsis was presumed where ≥2 of 4 systemic inflammatory response syndrome (SIRS) criteria were satisfied associated with a documented or highly suspected infection. Variables were assessed for normality using the D'Agostino-Pearson test. Continuous variables were compared between groups using the Mann-Whitney U test. Differences in frequency between categorical variables were analyzed using contingency tables, calculation of Fisher's exact test or Chi² and estimation of odds ratios. Results: In the study period, 47,992 phosphate concentration measurements from 23,752 unique dogs were identified. After eliminating repeat analyses, the period prevalence of hypophosphatemia on a per dog basis over the 11-year study period was 10.6% (2,515/23,752). The prevalence of presumptive sepsis within dogs with hypophosphatemia was 10.7% (268/2,515). During the 11-year study period, 4,406 dogs with an infection were identified, of which 1,233 were diagnosed with presumptive sepsis and had a contemporaneous phosphate concentration. Hypophosphatemia was more prevalent in dogs with presumptive sepsis than in dogs without 21.7 vs. 10.2%; OR 2.44 [95% CI 2.12-2.81]; P < 0.0001. The mortality rate was greater in dogs with hypophosphatemia and presumptive sepsis than in dogs with hypophosphatemia without presumptive sepsis (15.3 vs. 3.1%; OR 5.70 [95% CI 3.76-8.52]; P < 0.0001), however hypophosphatemia was not associated with outcome in dogs with presumptive sepsis OR 0.87 [95% CI 0.60-1.26]; P = 0.518. Conclusions: In dogs with hypophosphatemia, a presumed diagnosis of sepsis was associated with increased mortality compared to other associated disease processes. In dogs with presumptive sepsis, hypophosphatemia was not associated with outcome.

Effect of time until sample analysis on lactate in dogs with shock

INTRODUCTION

Lactate concentrations can increase with hypoperfusion in dogs and could be used as a prognostic indicator in sick dogs. In a busy emergency service, sample evaluation could be delayed. However, sample evaluation delays have been shown to cause lactate concentration increases in healthy dogs. In sick dogs, the magnitude of increased lactate is unknown. The goal of this study was to prospectively evaluate the effect of room temperature storage times on lactate measurements in dogs presenting to an emergency service.

METHODS

We evaluated the precision and accuracy of the NOVA Lactate Plus, using standard procedures. To assess the impact of time on lactate concentrations in sick dogs, we prospectively enrolled dogs presenting to an emergency service. Lactate concentrations were measured at six time points using samples stored at room temperature. A Friedman test, followed by a Wilcoxon rank test with a Bonferroni correction was used to evaluate time points.

RESULTS

Forty-five dogs were enrolled in this prospective observational study. The Lactate Plus and table-top analyzer compared favorably, with an R² of .98, and a mean bias of 0.26 in 50 canine samples. Precision was acceptable, with a percent coefficient of variation of 5.39. Statistically significant increases in lactate concentrations were found at all time points over baseline (P = .008).

CONCLUSIONS

In as little as 7.5 minutes, lactate concentrations increased significantly in samples stored at room temperature. Dogs with lower initial lactate concentrations had had higher increases in lactate concentration percentages over 90 minutes.

Outcomes of dogs undergoing immediate or delayed surgical treatment for gastrointestinal foreign body obstruction: A retrospective study by the Society of Veterinary Soft Tissue Surgery

OBJECTIVE

To evaluate gastrointestinal injury and outcomes between dogs treated with immediate surgical intervention vs those treated with delayed surgical intervention for gastrointestinal foreign body obstruction (GIFBO).

STUDY DESIGN

Retrospective cohort study.

SAMPLE POPULATION

Client-owned dogs (n = 855) from five referral hospitals.

METHODS

Medical records of dogs in which GIFBO had been diagnosed between 2007 and 2017 were reviewed for preoperative management, timing of surgery, intraoperative findings, postoperative management, outcome, and survival. Surgical intervention was classified as immediate when it occurred within 6 hours of presentation and delayed when it occurred >6 hours after presentation.

RESULTS

Outcomes did not differ between dogs treated immediately (n = 584) or over 6 hours after presentation (n = 210). Intestinal necrosis and perforations were more common when surgery was delayed (P = .008; P = .019) but became nonsignificant after controlling for preoperative differences. Risk factors for necrosis and perforations included duration of clinical signs, increased lactate, linear foreign material, and timing of surgery. Enterectomies (P = .004) as well as the duration of surgery (P = .004) and anesthesia (P = .001) were increased when surgery was delayed. Immediate surgery was associated with earlier return to feeding (P = .004) and discharge from the hospital (P < .001); (5%) dogs in each group (n = 33 immediate; n = 11 delayed) either had a negative explore or the foreign body was milked aborally into the colon at the time of surgery.

CONCLUSION

Although outcomes were not associated with surgical timing, the unadjusted prevalence of gastrointestinal injury and, thus, the requirement for complex surgical procedures was higher in the delayed group.

CLINICAL SIGNIFICANCE

Earlier surgical treatment of stabilized dogs with GIFBO may involve fewer complex procedures and accelerate recovery.

Factors associated with dehiscence and mortality rates following gastrointestinal surgery in dogs

OBJECTIVE

To identify factors associated with dehiscence and mortality rates following gastrointestinal surgery in dogs.

ANIMALS

170 client-owned dogs that underwent gastrointestinal surgery from 2010 to 2016.

PROCEDURES

Medical records of all included dogs were reviewed to collect information on preoperative (breed, sex, age, body weight, American Society of Anesthesiologists [ASA] physical status classification, emergency status, and plasma lactate concentration), intraoperative (indication for surgery, type of surgery, and whether bacterial peritonitis was identified), and postoperative (development of dehiscence and survival status at 2 weeks after surgery) factors. Preoperative and intraoperative factors were evaluated for associations among each other and with postoperative factors.

RESULTS

Univariate analyses revealed that preoperative plasma lactate concentration increased with increasing ASA status, and lactate concentrations were significantly higher for nonsurvivors (mean ± SD, 4.6 ± 3.7 mmol/L) than for survivors (2.4 ± 1.7 mmol/L). Multivariate analysis controlling for age, body weight, and plasma lactate concentration revealed that dogs with an ASA status ≥ 3 were more likely to develop dehiscence after gastrointestinal surgery than were dogs with a lower ASA status (OR, 17.77; 95% confidence interval, 2.17 to 144.06). Multivariate analysis also revealed that dogs with an ASA status ≥ 3 or high lactate concentration were less likely to survive than were other dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

These findings regarding ASA status and preoperative plasma lactate concentration and their associations with outcome may help clinicians to determine and provide optimal perioperative care to dogs requiring gastrointestinal surgery as well as to inform owners about prognosis.

Recognition, Treatment, and Monitoring of Canine Hypovolemic Shock in First Opinion Practice in the United Kingdom

The aim of this study was to gain a greater understanding of the detection, treatment, and monitoring of hypovolemic shock (HVS) in dogs by general practitioners in the United Kingdom (UK). An online survey was devised and distributed by email to first opinion practices in the UK. All veterinarians working in first opinion practice treating small animals were eligible to complete the survey. Most respondents (n = 164, 93%) were confident with HVS diagnosis. Isotonic crystalloid fluids were the most common fluid type for first-line treatment and administered as a 10-30 mL/kg bolus over 10-30 minutes by 57% respondents. Initial intravenous isotonic crystalloid fluid rates for HVS management ranged from maintenance fluid requirements to 90 mL/kg/hr for an undefined time period. A synthetic colloid was the most popular second-line fluid choice, typically considered after a total administered volume of 60-90 mL/kg of isotonic crystalloid fluids. Only 72 respondents (40.7%) were able to measure blood lactate in-house, which was used routinely by 36 respondents (20.3%) for initial treatment decision making. Respondents treating HVS most frequently were more likely to use lactate for initial decision making (P = .008). This study highlighted variabilities in the initial approach, fluid management strategies and monitoring instituted by UK general practitioners when faced with canine patients in HVS. This suggests that there is a discrepancy in what is determined to be the most optimal diagnostic and treatment plan for canine HVS patients.

Identification of risk factors for recurrent secondary septic peritonitis following initial surgical treatment of secondary septic peritonitis in dogs

OBJECTIVES

To report the incidence of and risk factors for development of recurrent secondary septic peritonitis (RSSP) in dogs. To report the outcome of dogs treated surgically for RSSP.

DESIGN

Retrospective study.

SETTING

University teaching hospital.

ANIMALS

One hundred forty-nine client-owned dogs treated surgically for secondary septic peritonitis (SSP).

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

The medical records database was searched for dogs that underwent surgery to treat SSP. Of 149 dogs that met the inclusion criteria, 15 (10.1%) dogs developed RSSP following surgery and 134 (89.9%) did not. Dogs with RSSP had significantly lower albumin prior to the first surgery to treat secondary septic peritonitis (SPsx1) (median 18 g/L [1.8 g/dL] vs 22 g/L [2.2 g/dL], P = 0.005) and significantly higher PCV prior to SPsx1 (median 52% vs 45%, P = 0.028). Dogs with septic peritonitis of gastrointestinal (GI) origin were significantly more likely to develop recurrent peritonitis than those with sepsis from a non-GI source (odds ratio [OR], 4.4, 95% CI: 0.95-20, P = 0.041). Of dogs with sepsis of GI origin, those with sepsis due to a foreign body were significantly more likely to develop RSSP than those with GI sepsis from a non-foreign body cause (OR, 7.2, 95% CI: 1.6-43, P = 0.0018). Of the 15 dogs in the RSSP group, 8 were euthanized without further treatment. Relaparotomy was performed in the remaining 7 cases; 3 of these (42.9%) survived.

CONCLUSIONS

There was a 10.1% rate of RSSP following SPsx1. Preoperative albumin was significantly lower and preoperative PCV was significantly higher in dogs that developed recurrence. Dogs with GI sepsis were at increased risk of recurrence and, among dogs with GI sepsis, the presence of a foreign body was an additional risk factor for recurrence.

Retrospective study of complications associated with surgically-placed gastrostomy tubes in 43 dogs with septic peritonitis

OBJECTIVES

To determine the safety of surgically-placed gastrostomy feeding tubes in dogs with septic peritonitis.

MATERIALS AND METHODS

Retrospective analysis of 43 dogs with septic peritonitis that had undergone surgical exploration and gastrostomy tube (de Pezzer or Foley) placement as part of the surgical procedure. Postoperative recovery times, hospitalisation times, complication rates and overall survival times were documented.

RESULTS

The most common cause of septic peritonitis was dehiscence of an enterotomy or enterectomy site. Fifteen dogs had a Foley gastrostomy tube placed and 28 had a de Pezzer gastrostomy tube placed. The median time from surgery to the start of enteral nutrition was 16 hours (range 3 to 28 hours). There were no major complications relating to the gastrostomy tube; minor complications occurred in 11 (26%) patients. The overall median time spent in hospital was 5 days (range 3 to 29 days) for patients surviving to discharge and 22 (51%) dogs survived overall.

CLINICAL SIGNIFICANCE

Gastrostomy feeding tubes provide a safe way to provide enteral nutrition to dogs with septic peritonitis; they are associated with a low complication rate in these patients.

Prognostic indicators in cats with septic peritonitis (2002-2015): 83 cases

OBJECTIVE

To identify physical exam findings, clinicopathological parameters, time to surgery, empirical antimicrobial use, and culture results that could be associated with outcome in cats with septic peritonitis (SP).

DESIGN

Retrospective cohort study of cats from 2002 to 2015.

SETTING

Four university teaching hospitals.

ANIMALS

Eighty-three cats diagnosed with SP by cytology or culture.

INTERVENTIONS

None MEASUREMENTS AND MAIN RESULTS: Fifty-eight cats survived to discharge (69.9%); 1 cat was euthanized in surgery; 20 were euthanized postoperatively; 4 cats suffered cardiac arrest after surgery. The most common etiology of SP was secondary SP due to gastrointestinal perforation (49.4%), followed by primary SP (22.3%). Mean blood glucose concentration was significantly different between survivors and nonsurvivors (P = 0.006). Cats that received appropriate empirical antibiotic therapy were 4.4 times more likely to survive than cats that did not receive appropriate antibiotics (P = 0.018).

CONCLUSIONS

As previously documented, SP secondary to gastrointestinal leakage was the most common etiology. In this population, cats with a higher blood glucose concentration on presentation had a worse prognosis. Cats that received appropriate empirical antimicrobial therapy were more likely to survive.

Utility of admission lactate concentration, lactate variables, and shock index in outcome assessment in dogs diagnosed with shock

OBJECTIVE

To determine whether admission venous plasma lactate concentration, calculated lactate variables, or shock index (SI) could discriminate hospital survivors from nonsurvivors in dogs admitted with shock.

DESIGN

Prospective investigation performed over a 19-month period.

SETTING

Large urban private teaching hospital.

ANIMALS

Twenty-three dogs consecutively admitted to the ICU from January 2008 to July 2009 with initial peripheral venous plasma lactate concentration >2 mmol/L (18.0 mg/dL) and clinical and hemodynamic parameters consistent with shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Heart rate, systolic blood pressure, and venous plasma lactate concentrations were serially recorded at predefined time points and used to calculate SI (SI = heart rate/systolic blood pressure) and lactate variables, including lactime (time lactate > 2.0 mmol/L), lactate clearance ([lactate_initial - lactate_delayed ]/lactate_initial × 100), and LAC_AREA (area under the lactate concentration versus time curve). Primary outcome was survival to discharge. Overall survival rate was 61%. Admission venous plasma lactate concentration did not differ between groups (P = 0.2). Lactime was shorter in survivors versus nonsurvivors (P = 0.02). Lactate clearance at 1, 10, 16, 24, and 36 hours, and final lactate clearance were greater in survivors versus nonsurvivors (P < 0.05). LAC_AREA at time intervals 0-1, 1-4, 4-10, 10-16, 16-24, 24-30, and 30-36 hours was larger in nonsurvivors versus survivors (P < 0.05). Total LAC_AREA did not differ between groups (P = 0.09). Admission SI and time to normalize SI (SI < 0.9) were not different between survivors and nonsurvivors (P > 0.05).

CONCLUSIONS

While admission venous plasma lactate concentration could not discriminate between hospital survivors and nonsurvivors, lactate variables showed clinical utility to predict outcome in dogs with shock. Further studies are needed to determine SI reference ranges and optimal SI cut-off values to improve its prognostic ability in sick dogs.

Biomarker Guided Diagnosis of Septic Peritonitis in Dogs

Septic peritonitis (SP) is common in dogs and is associated with high mortality. Early recognition is essential to maximizing survival and may be aided by biomarker measurement. The present study aimed to evaluate the ability of biomarkers to discriminate septic peritonitis from non-septic ascites (NSA). Eighteen dogs with SP and 19 age-matched controls with NSA were enrolled. Contemporaneous blood and peritoneal effusion samples were obtained. Concentrations of cell-free DNA (cfDNA), cytokines, glucose, lactate, N-terminal pro-C-type natriuretic peptide (NT-proCNP), nucleosomes, and procalcitonin (PCT) were measured using commercial reagents and assays. Paired biomarker concentrations were compared with the Wilcoxon matched-pairs signed rank test, and biomarker concentrations between groups were compared with the Mann-Whitney U-test. P-values were adjusted for multiple comparisons using the Bonferroni correction. Receiver operating characteristic curves were generated to assess the ability of the above biomarkers to discriminate SP from NSA. Dogs with SP had significantly greater blood CCL2 concentrations than dogs with NSA (P = 0.032). Dogs with SP had significantly greater effusion CCL2, IL-6, IL-10, and lactate concentrations than dogs with NSA (P ≤ 0.0121). Blood-effusion concentration gradients of CCL2, glucose, IL-6, IL-10, and lactate were significantly different in dogs with SP compared to dogs with NSA (P ≤ 0.0165). Effusion lactate concentration had the highest AUROC value (0.866, 95% CI 0.751–0.980, P = 0.0001), although other biomarkers performed similarly. An effusion lactate concentration of 4.2 mmol/L was 72.2% (95% CI 46.5–90.3%) sensitive and 84.2% (95% CI 60.4–96.6%) specific for the diagnosis of SP.

Retrospective evaluation of the route and timing of nutrition in dogs with septic peritonitis: 68 cases (2007-2016)

OBJECTIVE

To determine the impact of route of nutrition on length of hospitalization and survival to discharge in dogs with septic peritonitis.

DESIGN

Retrospective study from 2007 to 2016.

SETTING

University teaching hospital.

ANIMALS

Sixty-eight dogs with septic peritonitis that survived ≥48 hours.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Nutritional strategy was categorized into 1 of 4 groups: voluntary, feeding tube, parenteral (PN), and combined feeding tube and PN. Body weight, body condition score, time without caloric intake before and during hospitalization, length of hospitalization, and percentage of resting energy requirements provided during the first 3 days of nutritional support were recorded. Overall, 54/68 dogs survived (79%). Survival Prediction Index 2 scores were not significantly different between groups. Dogs receiving PN only were less likely to survive than those receiving any enteral nutrition (OR 9.7; 95CI 1.84-58.75). Compared to dogs not receiving PN, dogs receiving any PN were significantly less likely to survive (OR 9.66; 95% CI 1.7-105.8), and were in hospital significantly longer (P = 0.025). Metabolic complications associated with PN were frequent but not associated with increased length of hospitalization or survival to discharge.

CONCLUSIONS

Dogs with septic peritonitis that received any PN were in hospital longer and less likely to survive but may have been sicker than those receiving other forms of nutritional support. Further studies are warranted to evaluate reasons for worse outcomes in dogs with septic peritonitis receiving PN.

Evaluation of tissue oxygen saturation in naturally occurring canine shock patients

OBJECTIVE

To measure tissue oxygen saturation (StO₂ ) in a population of dogs with naturally occurring shock and to evaluate the relationship of StO₂ with an established veterinary severity scoring system (Acute Patient Physiologic and Laboratory Evaluation) and patient survival.

DESIGN

Prospective observational study.

SETTING

University teaching hospital.

ANIMALS

Twenty-five adult dogs presenting in shock, as determined by the presence of hypotension, the calculated shock index, and hyperlactatemia.

INTERVENTIONS

StO₂ was measured prior to any therapeutic interventions. Blood samples were also collected for measurement of plasma lactate, complete blood count, and a serum biochemical profile. Abdominal and thoracic focused assessment with sonography was also performed.

MEASUREMENTS AND MAIN RESULTS

Dogs enrolled in this study had lower mean (±SD) StO₂ values (65.12 ± 17.7%) than previously reported in experimental models of canine hemorrhagic shock. There was a moderate correlation between lower StO₂ and increasing Acute Patient Physiologic and Laboratory Evaluation scores. A single StO₂ value, assessed prior to therapeutic intervention, was not a sensitive predictor of mortality in this population.

CONCLUSIONS

Dogs with naturally occurring shock have lower mean StO₂ values than those previously reported in dogs with experimentally induced shock. A lower initial StO₂ was associated with worse disease severity but was not a significant predictor of survival in this population.

Utility and Prognostic Significance of Neutrophil-to-Lymphocyte Ratio in Dogs with Septic Peritonitis

Systemic inflammation is known to cause WBC abnormalities, specifically neutrophilia and lymphopenia. The neutrophil-to-lymphocyte ratio (NLR) is a simple and affordable biomarker that has been used in human clinical settings of sepsis but has not been investigated in veterinary species. We evaluated NLR in dogs with septic and nonseptic systemic inflammatory diseases and compared with a healthy dog population. An NLR ≥6 had an 84.39% sensitivity and 86.95% specificity to identify dogs with systemic inflammatory states; however, no ratio distinguished septic and nonseptic causes. The NLR was not associated with length of hospitalization, morbidity based on the acute patient physiologic laboratory evaluation scoring system, or mortality. The disassociation may be due to the retrospective nature of the study, including a restricted population size and acquisition of only a one-time blood sample. NLR is currently of limited use for diagnosis and prognosis in systemic inflammatory states in dogs, and larger, prospective studies are necessary to further evaluate NLR.

Clinical use of plasma lactate concentration. Part 2: Prognostic and diagnostic utility and the clinical management of hyperlactatemia

OBJECTIVE

To review the current literature pertaining to the use of lactate as a prognostic indicator and therapeutic guide, the utility of measuring lactate concentrations in body fluids other than blood or plasma, and the clinical management of hyperlactatemia in dogs, cats, and horses.

DATA SOURCES

Articles were retrieved without date restrictions primarily via PubMed, Scopus, and CAB Abstracts as well as by manual selection.

HUMAN AND VETERINARY DATA SYNTHESIS

Increased plasma lactate concentrations are associated with increased morbidity and mortality. In populations with high mortality, hyperlactatemia is moderately predictive in identifying nonsurvivors. Importantly, eulactatemia predicts survival better than hyperlactatemia predicts death. Consecutive lactate measurements and calculated relative measures appear to outperform single measurements. The use of lactate as a therapeutic guide has shown promising results in people but is relatively uninvestigated in veterinary species. Increased lactate concentrations in body fluids other than blood should raise the index of suspicion for septic or malignant processes. Management of hyperlactatemia should target the underlying cause.

CONCLUSION

Lactate is a valuable triage and risk stratification tool that can be used to separate patients into higher and lower risk categories. The utility of lactate concentration as a therapeutic target and the measurement of lactate in body fluids shows promise but requires further research.

Evaluation of the association between strong ion acid-base disturbances and mortality in dogs: a retrospective study

Acid-base abnormalities are frequently encountered in veterinary emergency and critical care, but information regarding the prognostic value of these findings is limited. Several systems for analysing acid-base disturbances have been reported, but the prognostic abilities of these systems have not been compared in dogs. The objectives of this retrospective study were to determine if the commonly used acid-base interpretation methods (Henderson-Hasselbalch, Stewart and semi-quantitative) have prognostic value, and to compare the performance of the three methods. Electronic medical records were searched to create a database containing point-of-care blood-gas, electrolyte and serum chemistry values for 1024 dogs assessed at a university teaching hospital. Dogs with contemporaneous blood-gas analysis, blood lactate and serum biochemistry samples were eligible for study, and only the first recorded analyses for each patient visit were included. Components of the Henderson-Hasselbalch, Stewart and semi-quantitative methods were calculated. To assess prognostic ability and to compare analysis system performance, receiver-operating characteristic (ROC) curves for survival to hospital discharge were created. Of the 1024 dogs identified, case fatality rate was 23.8%. Area under the ROC curve did not exceed 0.63 for any calculated variable. Performance of all three analysis systems was similar. While some acid-base abnormalities identified were associated with mortality, no individual abnormality or system output yielded sensitive and specific cut-off values for mortality prediction, and no interpretation method outperformed the others. This study suggests that initial acid-base abnormalities have limited prognostic utility and that various analysis systems can be used to assess acid-base disturbances in critically ill dogs.

Retrospective evaluation of plasma cholesterol concentration in septic dogs and its association with morbidity and mortality: 51 cases (2005-2015)

OBJECTIVE

To determine whether plasma cholesterol concentrations in dogs with sepsis is associated with morbidity or in-hospital mortality.

DESIGN

Retrospective cohort study from 2005-2015.

SETTING

Two private referral centers.

ANIMALS

Fifty-one dogs diagnosed with sepsis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Dogs were classified as septic if they displayed ≥2 criteria of the systemic inflammatory response syndrome in conjunction with a documented underlying infectious cause. Dogs were excluded if they had been diagnosed previously with any concurrent illness reported to alter plasma cholesterol concentrations. Plasma cholesterol concentrations at the time of sepsis diagnosis were statistically analyzed for association with morbidity, as measured by the presence of organ dysfunction, the number of dysfunctional organs, duration of hospitalization, cost of hospitalization, and in-hospital mortality. Twenty-eight (55%) dogs survived to discharge, 15 (29%) were euthanized during hospitalization, and 8 (16%) died despite treatment. While median cholesterol concentrations were significantly different when comparing survivors to discharge versus nonsurvivors who died naturally despite treatment (P = 0.0245), they were not significantly different when comparing survivors to all nonsurvivors (P = 0.1821). Receiver operating characteristic curve analysis showed a cholesterol cutoff of 4.5 mmol/L (174 mg/dL) with a sensitivity of 75% and a specificity of 50% for predicting in-hospital mortality. For surviving dogs, plasma cholesterol concentrations were not associated with increased length of hospital stay. Number of dysfunctional organs and plasma cholesterol concentration were the 2 most significant individual predictors for survival, and when incorporated into a multivariate logistic regression model used for prediction, the model yielded a sensitivity of 94% and specificity of 63%.

CONCLUSION

Plasma cholesterol concentration can provide prognostic information in dogs with sepsis. Further prospective studies investigating the role of cholesterol in sepsis are needed.

Assessment of a portable lactate meter for field use in the white rhinoceros (<i>Ceratotherium simum</i>)

Blood lactate is a predictor of mortality in critically ill humans and animals. Handheld lactate meters have the potential to be used in the field to evaluate the condition of severely injured rhinoceroses but have not been compared with laboratory-based methods. Agreement between a handheld lactate meter and a laboratory method was assessed, as was the stability of rhino blood lactate in the anticoagulant sodium fluoride/potassium oxalate (fluoride/oxalate). Blood samples were obtained from 53 white rhinos that had been immobilised for management reasons. Lactate was measured by means of a handheld meter using whole blood in heparin (WBHEP), whole blood in fluoride/oxalate (WBFO) and fluoride/oxalate plasma (PFO). Results were recorded in both blood (BL) and plasma (PL) modes and compared to an established laboratory method for measuring plasma lactate. To assess the stability of lactate over time, blood lactate in fluoride/oxalate was measured on the handheld meter at intervals for up to 91 h. Agreement was best using WBFO in PL mode, with small bias (−0.16), tight 95% limits of agreement (LOA) (−1.46, 1.14) and a Pc (95% CI) of 0.97 (0.92, 0.99). The agreement was improved for all sample types when using the PL mode compared to the blood lactate (BL) mode. Blood lactate was stable in fluoride/oxalate for 91 h, with a mean change from baseline of 0.15 (−0.178, 0.478) mmol/L (mean, 95% CI). The handheld meter was found to be suitable for field use in white rhinos but provided more reliable results with the device in PL mode. Furthermore, rhino blood lactate was found to be stable in fluoride/oxalate for as long as 3 days.

A pilot study evaluating the prognostic utility of platelet indices in dogs with septic peritonitis

OBJECTIVE

To characterize platelet indices at time of diagnosis of septic peritonitis in dogs and to assess the relationship between platelet parameter data and survival to discharge in dogs treated surgically.

DESIGN

Retrospective, observational, descriptive pilot study from 2009 to 2014.

SETTING

University teaching hospital.

ANIMALS

Forty-eight dogs diagnosed with septic peritonitis were included in this study. Thirty-six dogs had surgical source control. Blood samples from 46 healthy control dogs were used for reference interval (RI) generation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Dogs with septic peritonitis had significantly increased mean values for mean platelet volume (MPV), plateletcrit (PCT), and platelet distribution width (PDW) with increased proportions of dogs having values above the RI compared to healthy dogs. A significantly increased proportion of dogs with septic peritonitis had platelet counts above (12.5%) and below (8.3%) the RI, with no significant difference in mean platelet count compared to healthy dogs. No significant differences in the mean platelet count, MPV, PCT, or PDW were found between survivors and nonsurvivors in dogs with surgical source control; however, dogs with MPV values above the RI had significantly increased mortality compared to dogs within the RI (P = 0.025). Values outside the RI for other platelet parameters were not associated with significant differences in mortality.

CONCLUSIONS

Dogs with septic peritonitis have increased frequency of thrombocytosis and thrombocytopenia with increased MPV, PCT, and PDW. An increased MPV may be a useful indicator of increased risk of mortality in dogs treated surgically.

Evaluation of the Safety of Early Compared to Late Enteral Nutrition in Canine Septic Peritonitis

Septic peritonitis is a relatively common condition in the veterinary intensive care unit, with a classically high mortality rate. Early enteral nutrition (EEN) in critically ill humans can lead to improved outcome. This study was performed to determine the safety of early postoperative feeding in canine septic peritonitis. In this retrospective case series, 56 dogs were identified. Sixteen dogs received EEN, defined as nutrition within 24 hr of surgery; 27 received late enteral nutrition (LEN) defined as nutrition more than 24 hours following surgery; and 13 dogs had no enteral nutrition in hospital (NEN). Signalment, physical examination findings, and occurrence of pre-admission vomiting, regurgitation, and length of anorexia were the same amongst all groups. There was no significant difference in the number of gastrointestinal complications postoperatively between the EEN, LEN, and NEN groups or in the occurrence of vomiting/regurgitation postoperatively compared to preoperatively. There was no difference in the length of hospitalization between any group, although fewer dogs in the NEN group survived compared to the EEN/LEN combined group (46% [6/13] versus 81% [37/40]). This study indicates it is safe to initiate EEN without additional risk of gastrointestinal complications. Prospective studies are needed to evaluate the potential benefits of EEN in dogs with septic peritonitis.

Update: Clinical Use of Plasma Lactate

Lactate is an essential, versatile metabolic fuel in cellular bioenergetics. In human emergency and critical care, lactate is used as a biomarker and therapeutic endpoint and evidence is growing in veterinary medicine supporting its clinical utility. Lactate production is a protective response providing ongoing cellular energy during tissue hypoperfusion or hypoxia and mitigating acidosis. Hence, hyperlactatemia is closely associated with disease severity but it is an epiphenomenon as the body attempts to protect itself. This article reviews lactate biochemistry, kinetics, pathophysiology, some practical aspects of measuring lactate, as well as its use in diagnosis, prognosis, and monitoring.

Point of Care Measurement of Lactate

Lactate is generated as a consequence of anaerobic glycolysis by all tissues of the body. Increased l-lactate, the isoform produced by most mammals, reflects increased anaerobic metabolism secondary to tissue hypoperfusion or tissue hypoxia in most clinical situations, and is called type A lactic acidosis. The utility of lactate measurement and serial lactate monitoring in veterinary patients has been demonstrated in multiple studies. Blood lactate concentration is significantly elevated in many disease processes including septic peritonitis, immune-mediated hemolytic anemia, Babesiosis, trauma, gastric dilation and volvulus, and intracranial disease. Lactate clearance can be used to assess response to fluid therapy, cardiovascular therapeutics, and blood product transfusion in patients affected by type A lactic acidosis. Lactate concentration in peritoneal, pericardial, and synovial fluid can also be used as a diagnostic tool. Point of care analyzers such as the Lactate Pro, Lactate Scout, Accutrend, iSTAT, and Lactate Plus have been shown to be accurate lactate measurement instruments in small animal patients.

Prognostic Markers in Acute Babesia canis Infections

Background

Canine babesiosis, caused by Babesia canis, is a prevalent and clinically relevant disease in Europe. Severe acute babesiosis is characterized by a high mortality but prognosis is not always correlated with clinical signs nor with the level of parasitemia.

Objective

This study evaluated prognostic markers associated with poor outcomes in acute Babesia canis infections.

Animals and Methods

We compared the results of routine laboratory profiles, hand‐held lactate and glucose analyzer, and the acute phase response in 2 groups of naturally infected dogs (7 survivors and 8 nonsurvivors). Samples were collected at the time of first admission and before any treatment. Subsequently, the course of prognostic markers was followed in 3 dogs experimentally inoculated with B. canis.

Results

Nonsurvivors showed significantly higher concentrations of lactate, triglycerides and phosphate and lower hematocrit, leukocyte counts, total serum protein concentrations, and thrombocyte counts when compared to survivors. All nonsurvivors (8/8) had hyperlactatemia, whereas most survivors (6/7) had values within the reference range. All survivors had leucocyte counts within the reference range, unlike the nonsurvivors, which showed leukopenia. During the course of acute babesiosis, the variables serum lactate, triglyceride, and phosphate concentrations, and thrombocyte count only exceeded a prognostic threshold during acute crisis.

Conclusions and clinical importance

Poor outcome in acute B. canis infection is indicated by changes in the laboratory profile. Intensive care should be considered for dogs presenting with moderate anemia, severe thrombocytopenia, mild to moderate leukopenia, hyperlactatemia, moderately increased serum phosphate, and triglyceride concentrations, and moderately decreased total serum protein concentrations.