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

Effect of systemic inflammatory response syndrome on thrombocytogram, acute phase proteins, electrolytes, acid-base indices and cytokine expression in naturally canine parvovirus infected dogs

Systemic inflammatory response syndrome (SIRS) in canine parvoviral enteritis (CPVE) is associated with high mortality in young puppies. Changes in acute phase response, thrombocytogram, inflammatory cytokine profiles, and disturbances in electrolyte and acid-base homeostasis are thought to have a significant impact on the development of SIRS. However, the mechanisms causing these perturbations have not been well described in CPVE puppies, especially with SIRS. The purpose of this study was to assess the changes of electrolytes, acid-base indices using strong ion model, acute phase proteins and thrombocytogram in blood and expressions of inflammatory cytokines in blood mononuclear cells of CPVE puppies with or without SIRS at admission. Additionally, the positive predictive value (PPV) and cut-off value with specificity and sensitivity of the biomarkers were determined by receiver operating characteristic (ROC) curve analysis to predict the development of SIRS in CPVE puppies at admission. A case-controlled, prospective and observational study was conducted on fifteen SIRS-positive CPVE, twenty-one SIRS-negative CPVE and six healthy puppies. Our data showed marked hyponatremia, hypokalemia, hypoalbuminemia and hypoproteinemia, decreased A_Tot-albumin and A_{Tot-total protein} and increased mean platelet volume (MPV), platelet distribution width (PDW) and C-reactive protein (CRP) concentration and up-regulation of TNF-α, IL-8 and IL-10 expressions in SIRS-positive CPVE puppies as compared to SIRS-negative CPVE puppies at admission. Based on sensitivity, specificity and AUC from ROC curve analysis and PPV, the CRP concentration in serum at a cut-off value of 141.9 mg/L and TLC of blood at a cut-off value of 3.355 × 10³/μL were identified as potential prognostic biomarkers followed by A_{Tot-total protein} and total protein at a cut-off value of 11.80 and 4.72 g/dL, respectively to predict the development of SIRS in CPVE puppies at admission. In conclusion, the findings of the current study will help the canine practitioners to institute the time-sensitive and need based interventions to disrupt progression along the continuum of shock and multi-organ dysfunction syndrome in CPVE puppies that develop SIRS at admission.

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.

Biological evaluation of a mechanical ventilator that operates by controlling an automated manual resuscitator. A descriptive study in swine

The Covid-19 outbreak challenged health systems around the world to design and implement cost-effective devices produced locally to meet the increased demand of mechanical ventilators worldwide. This study evaluates the physiological responses of healthy swine maintained under volume- or pressure-controlled mechanical ventilation by a mechanical ventilator implemented to bring life-support by automating a resuscitation bag and closely controlling ventilatory parameters. Physiological parameters were monitored in eight sedated animals (t₀) prior to inducing deep anaesthesia, and during the next six hours of mechanical ventilation (t₁-₇). Hemodynamic conditions were monitored periodically using a portable gas analyser machine (i.e. BEecf, carbonate, SaO₂, lactate, pH, PaO₂, PaCO₂) and a capnometer (i.e. ETCO₂). Electrocardiogram, echocardiography and lung ultrasonography were performed to detect in vivo alterations in these vital organs and pathological findings from necropsy were reported. The mechanical ventilator properly controlled physiological levels of blood biochemistry such as oxygenation parameters (PaO₂, PaCO₂, SaO₂, ETCO₂), acid-base equilibrium (pH, carbonate, BEecf), and perfusion of tissues (lactate levels). In addition, histopathological analysis showed no evidence of acute tissue damage in lung, heart, liver, kidney, or brain. All animals were able to breathe spontaneously after undergoing mechanical ventilation. These preclinical data, supports the biological safety of the medical device to move forward to further evaluation in clinical studies.

A Preliminary Investigation into the Association of Chloride Concentration on Morbidity and Mortality in Hospitalized Canine Patients

Purpose

To evaluate whole blood chloride concentration and hospital-acquired AKI in hospitalized canine patients. Secondary outcome measures included the volume-adjusted chloride load, in-hospital mortality and length of ICU stay.

Patients and Methods

This is a prospective, observational study. Sixty dogs admitted to the ICU and receiving IV fluid therapy for >24 hours from February 2018 to July 2019. Corrected chloride and creatinine concentrations were obtained twice daily. Total volume of IV fluid and total chloride load were recorded. Volume-adjusted chloride load (VACL) was calculated by dividing the chloride administered by the volume of fluid administered. Hospital-acquired AKI was defined as an increase in creatinine of ≥26.5 μmol/L (0.3 mg/dL) or 150% from baseline to maximum. Survival to hospital discharge or non-survival and ICU length of stay were also recorded.

Results

Fifteen out of 60 patients developed hospital-acquired AKI. Maximum corrected chloride was significantly different in AKI group (median 122.3 mmol/L) vs non-AKI group (median 118.1 mmol/L; p=0.0002). Six out of 60 patients developed hyperchloremia. Hyperchloremic patients were significantly more likely to develop in-hospital AKI (p=0.03). Patients hospitalized ≥2 days had a significantly higher [Cl⁻]_max compared to those with shorter ICU stay (121.8 ± 5.9 mmol/L vs 117.5 ± 4.3 mmol/L; p=0.002). Eight out of 60 patients were non-survivors. Maximum corrected chloride and creatinine concentrations were not significantly different between survivors and non-survivors. VACL was not significantly different between AKI or mortality groups.

Conclusion

Maximum corrected chloride concentration was significantly higher in dogs with hospital-acquired AKI, even amongst dogs without hyperchloremia. Additionally, maximum corrected chloride concentrations were significantly higher in dogs hospitalized in the ICU longer compared to those hospitalized for fewer than two days. There was no significant difference in VACL in any of the outcome groups. Results from this study suggest alterations in chloride may be observed alongside the development of acute kidney injuries. Future studies in critically ill dogs are warranted.

Role of electrolyte abnormalities and unmeasured anions in the metabolic acid-base abnormalities in dogs with parvoviral enteritis

BACKGROUND

The strong ion model (SIM) is an alternative paradigm in the characterization of acid-base disturbances particularly in complex disorders.

HYPOTHESIS/OBJECTIVES

To compare the acid-base changes in dogs with parvoviral enteritis (PE) using the Henderson-Hasselbalch (HH) approach, with 2 strong ion approaches.

ANIMALS

Forty-four dogs with PE, and 16 age-matched control dogs.

METHODS

Prospective controlled observational study. Acid-base status was evaluated using the HH model, Fencl-Stewart (FS) approach and a validated strong ion model (VDM). The acid-base changes according to each model were classified and compared. Statistical correlations between pH, CO₂ , and various SIM variables were performed, as well as between the sum of effects (SOE) of the SIM and the individual variables comprising the SOE.

RESULTS

The HH model identified acid-base disorders in 31/44 cases of which 16/31 were mixed with metabolic acidosis and concurrent respiratory alkalosis the most common (10/31). Using the FS approach, metabolic changes were present 36/42 cases, with changes in free water (FW), chloride, and unmeasured anions (UA) being the most prevalent. Both FW and UA correlated well with pH; however, UA were most consistently abnormal in severe acidemia. Similarly to the HH, the VDM detected acid-base disturbances in 28/44 cases. Major contributors to the acid-base changes were hyponatremia, hypochloremia, and A_tot acidosis because of elevated globulins and increased UA.

CONCLUSIONS AND CLINICAL IMPORTANCE

Acid-base changes are common and complex in dogs with PE, and were easier to understand using a SIM paradigm. Increases in UA have not been documented in PE in dogs.

Higher Serum Uric Acid Level Predicts Non-alcoholic Fatty Liver Disease: A 4-Year Prospective Cohort Study

Background: Non-alcoholic fatty liver disease (NAFLD) has become a serious disease affecting people's health in the world. This article studies the causal relationship between NAFLD and serum uric acid (SUA) levels. Methods: During the 4 years of follow-up in a fixed cohort that was established in 2014, 2,832 follow-up subjects without NAFLD were finally included in this study. The study population was divided into four groups according to baseline SUA levels. Cox hazard regression model and Kaplan-Meier survival curves analysis were used to predict risk factors of NAFLD. The receiver operating characteristic curve analyses were used to determine SUA cutoffs for predicting NAFLD. Results: The cumulative prevalence rates of NAFLD were 33.97% (962/2,832), 38.93% (758/1,947) in males and 23.05% (204/885) in females. The results showed that males had a higher incidence of NAFLD (χ² = 68.412, P = 0.000). The Cox regression analysis disclosed that the hazard ratios of NAFLD [95% confidence interval (CI)] were 1.431 (95% CI, 1.123~1.823), 1.610 (95% CI, 1.262-2.054), and 1.666 (95% CI, 1.287-2.157) across the second to the fourth quartile of SUA adjusted for other confounders. The SUA cutoffs, sensitivity, specificity, and area under the curve (AUC) (95% CI) were ≥288.5 μmol/L, 75.5, 46.5%, 0.637(0.616-0.658), respectively, for total; ≥319.5 μmol/L, 65.8%, 48.4%, 0.590 (0.564-0.615), respectively, for males; and ≥287.5 μmol/L, 51.0%, 75.6%, 0.662 (0.619-0.704), respectively, for females. Kaplan-Meier survival curves revealed that individuals with higher SUA level had an increased risk of NAFLD in comparison to lower SUA level (P = 0.000). Conclusion: Serum uric acid is positively correlated with NAFLD, and elevated SUA level can be used as an independent predictor for NAFLD.

Severity of Ionized Hypercalcemia and Hypocalcemia Is Associated With Etiology in Dogs and Cats

Background: Calcium disorders are common in small animals, but few studies have investigated the etiology of ionized hypercalcemia and hypocalcemia in large populations. This study aimed to determine the incidence of ionized calcium disorders in dogs and cats treated at a tertiary referral clinic and to describe the associated diseases.

Methods: An electronic database of electrolyte analyses conducted at the Cornell University Hospital for Animals from 2007 to 2017 was searched. Dogs and cats with ionized hypercalcemia or hypocalcemia were identified based on institution reference intervals. Duplicate case entries were removed. Medical records were reviewed to identify the cause of the calcium abnormality. Chi-squared analysis with Bonferroni adjustment was performed to compare frequencies of disease processes between mild and moderate-severe disturbances.

Results: The database included 15,277 dogs and 3,715 cats. Hypercalcemia was identified in 1,641 dogs and 119 cats. The incidence of canine and feline hypercalcemia was 10.7 and 3.2%, respectively. Hypocalcemia was identified in 1,467 dogs and 450 cats. The incidence of canine and feline hypocalcemia was 9.6% and 12.1%, respectively. The most common pathologic causes of hypercalcemia in dogs were malignancy-associated (12.9%), parathyroid-dependent (4.6%) and hypoadrenocorticism (1.7%). In cats, malignancy-associated hypercalcemia (22.7%), kidney injury (13.4%) and idiopathic hypercalcemia (12.6%) were most common. Dogs presenting with moderate-severe hypercalcemia vs. mild hypercalcemia were significantly more likely to have hyperparathyroidism, malignancy-associated hypercalcemia or hypervitaminosis D, whereas cats were significantly more likely to have malignancy-associated hypercalcemia or idiopathic hypercalcemia. The most common pathologic causes of hypocalcemia in dogs were critical illness (17.4%), kidney injury (10.4%) and toxicity (7.5%). In cats, kidney injury (21.6%), urethral obstruction (15.1%), and critical illness (14.7%) were most frequent. Dogs presenting with moderate-severe hypocalcemia were significantly more likely to have hypoparathyroidism, kidney injury, eclampsia or critical illness, whereas cats were significantly more likely to have kidney injury, soft tissue trauma or urethral obstruction.

Conclusions: Mild calcium disturbances are most commonly associated with non-pathologic or transient conditions. Malignancy-associated hypercalcemia is the most common cause of ionized hypercalcemia in dogs and cats. Critical illness and kidney injury are frequent causes of ionized hypocalcemia in both species.