Ionized hypocalcemia as a prognostic indicator in dogs following trauma

Markers of tissue perfusion and their relation to mortality in dogs with blunt trauma

OBJECTIVE

To evaluate admission Animal Trauma Triage (ATT) score, shock index (SI), and markers of perfusion, including base excess (BE), plasma lactate, and lactate clearance in dogs with blunt trauma.

DESIGN

Prospective observational clinical study from 2013 to 2015.

SETTING

Private veterinary referral and emergency center.

ANIMALS

Forty-four client-owned dogs hospitalized following blunt trauma.

INTERVENTION

Within 1 hour of presentation and prior to fluid administration an initial hematocrit, total plasma protein, blood glucose, plasma lactate, blood gas, and electrolytes were obtained for analysis. Plasma lactate concentrations were also measured 4 and 8 hours following initial measurement, and a 4-hour lactate clearance was calculated if patients had an increased admission plasma lactate. ATT score and SI were calculated for each patient based on admission data. Outcome was defined as survival to hospital discharge.

MEASUREMENTS AND MAIN RESULTS

Twenty-nine dogs survived, 14 were euthanized, and 1 died. Nonsurviving dogs had a lower mean pH (7.28 ± 0.03 vs 7.36 ± 0.01, P = 0.006), lower median HCO₃ (15.7 vs 18.8 mmol/L, P = 0.004), lower median admission BE (-11.0 vs -7.0 mmol/L, P = 0.004), and higher median admission lactate (3.1 vs 2.4 mmol/L, P = 0.036) than those who survived. Median ATT was significantly higher in nonsurvivors (5 vsF 2, P < 0.001). The SI was not significantly different between survivors and nonsurvivors (P = 0.41). There was no difference in median 4-hour lactate (P = 0.34), median 8-hour lactate (P = 0.19), or 4-hour lactate clearance (P = 0.83) in survivors compared to nonsurvivors. No other statistically significant differences were noted between groups.

CONCLUSION

Dogs hospitalized following blunt trauma with a lower admission pH, HCO₃ , and BE and a higher admission plasma lactate were less likely to survive to hospital discharge. Median ATT score was also significantly higher in nonsurvivors. Although lactate clearance was not predictive of survival, the sample size was small, and additional studies with a larger study population are warranted.

Development of a veterinary trauma score (VetCOT) in canine trauma patients with performance evaluation and comparison to the animal trauma triage score: A VetCOT registry study

OBJECTIVE

To develop a population-derived, parsimonious, and objective risk stratification model for dogs following trauma and compare its predictive performance to the animal trauma triage (ATT) score.

DESIGN

Observational cohort study using data from the American College of Veterinary Emergency and Critical Care Veterinary Committee on Trauma (VetCOT) trauma registry acquired between September 2013 and October 2017.

SETTING

Nine Level I and Level II veterinary trauma centers.

ANIMALS

Nine hundred eighty-four dogs assessed within 24 h of traumatic injury.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patient mortality was 10.8%. The VetCOT model was constructed based on 4 variables: plasma lactate and ionized calcium obtained within 6 h of admission, and presence or absence of clinical signs consistent with either head or spinal trauma. The VetCOT score had good discriminatory performance (AUROC = 0.87, 95% CI = 0.83-0.91) comparable to that of the 6 variable ATT score for the same population (area under the receiver operator characteristic [AUROC] = 0.87; 95% CI, 0.84-0.90). No statistical difference in discriminatory performance between the 2 scores was identified (P = 0.98). The VetCOT score showed good calibration on this population (Hosmer-Lemeshow test P = 0.93), whereas the ATT score failed to calibrate (P = 0.02) due to overprediction of mortality at low scores. Sensitivity and specificity for outcome of the VetCOT score at a risk probability cutoff of 0.5 for this population were 28.97% and 97.95%, respectively.

CONCLUSIONS

The VetCOT score is a more parsimonious model with comparable discriminatory performance and superior calibration to the ATT score for risk stratification in dogs following trauma. Further prospective validation studies are required to confirm the discriminatory performance of the VetCOT score.

Volume Resuscitation in the Acutely Hemorrhaging Patient: Historic Use to Current Applications

Acute hemorrhage in small animals results from traumatic and non-traumatic causes. This review seeks to describe current understanding of the resuscitation of the acutely hemorrhaging small animal (dog and cat) veterinary patient through evaluation of pre-clinical canine models of hemorrhage and resuscitation, clinical research in dogs and cats, and selected extrapolation from human medicine. The physiologic dose and response to whole blood loss in the canine patient is repeatable both in anesthetized and awake animals and is primarily characterized clinically by increased heart rate, decreased systolic blood pressure, and increased shock index and biochemically by increased lactate and lower base excess. Previously, initial resuscitation in these patients included immediate volume support with crystalloid and/or colloid, regardless of total volume, with a target to replace lost vascular volume and bring blood pressure back to normal. Newer research now supports prioritizing hemorrhage control in conjunction with judicious crystalloid administration followed by early consideration for administration of platelets, plasma and red blood during the resuscitation phase. This approach minimizes blood loss, ameliorates coagulopathy, restores oxygen delivery and correct changes in the glycocalyx. There are many hurdles in the application of this approach in clinical veterinary medicine including the speed with which the bleeding source is controlled and the rapid availability of blood component therapy. Recommendations regarding the clinical approach to volume resuscitation in the acutely hemorrhaging veterinary patient are made based on the canine pre-clinical, veterinary clinical and human literature reviewed.

Clinicopathological abnormalities associated with increased animal triage trauma score in cats presenting for vehicular trauma: 75 cases (1998-2009)

OBJECTIVE

To document the clinical and clinicopathological changes in cats presenting with vehicular trauma (VT) and to determine whether the calculated animal trauma triage (ATT) score was associated with any clinicopathological abnormalities.

DESIGN

Retrospective descriptive study conducted between 1998 and 2009.

SETTING

University veterinary teaching hospital.

ANIMALS

Seventy-five client-owned cats that presented for VT to an urban veterinary hospital.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Pertinent history, physical examination findings, results of biochemical testing, and outcome were extracted from medical records. ATT score was calculated based on physical examination. Patients were classified as having either a low (<5) ATT (n = 30) or a high (≥5) ATT (n = 45) score. Male cats were overrepresented (60.0%), and a majority of cats had outdoor access (65.3%). Low PCV (P = 0.024), low total plasma protein concentration (P = 0.032), low venous blood pH (P = 0.047), high plasma lactate concentration (P = 0.047), low plasma bicarbonate concentration (P = 0.047), low base excess (P = 0.047), and high plasma glucose concentration (P = 0.047) were associated with higher ATT scores. In addition, low noninvasive blood pressure measurements (P = 0.008) were associated with higher ATT scores.

CONCLUSIONS

There was a significant association between lower PCV, lower total plasma protein concentration, lower venous blood pH, higher plasma lactate concentration, lower plasma bicarbonate concentration, lower base excess, higher whole blood glucose concentration, and lower noninvasive blood pressure and higher ATT scores at presentation in feline patients suffering from VT. Prospective evaluation of these values may prove useful in furthering understanding of the pathophysiology of trauma in cats.

Thyroid axis and adrenal activity in 28 day survivor and nonsurvivor dogs involved in recent road traffic accidents: A cohort study of 420 dogs

The objective of this retrospective cohort study was to determine the impact of a recent trauma on thyroid axis and adrenal activity in dogs and to assess the usefulness of urinary cortisol-to-creatinine ratio (UCCR), basal serum thyroid-stimulating hormone (TSH), total thyroxine (tT4), and free thyroxine (fT4) concentrations in predicting outcome in dogs traumatized by a road traffic accident (RTA). An RTA exposed group of 210 dogs was evaluated within 24  hours of the trauma. Their data were compared with data from a matched group of dogs with other diagnoses. UCCR was positively correlated with the trauma severity and was higher in the exposed group than in the nonexposed group (median 101.500 vs. 21.02; p < 0.0001). tT4 values were statistically similar between the two groups, but were correlated with a trauma score, while TSH (median = 0.050 vs. 0.080 ng/mL; p < 0.0001) and fT4 (median = 15.850 vs. 17.950 pmol/L; p = 0.0037) were significantly lower for the exposed group. Nonsurvivors in comparison to survivors presented and higher median UCCR (181.800 vs. 93.850 respectively; p = 0.020), and a lower serum fT4 (12.700 vs. 16.500 pmol/L, respectively; p = 0.0046). A similar pattern had been observed for tT4. TSH levels were not predictive of survival. This study provides insights into the endocrine characteristics of dogs suffering from acute trauma. UCCR was higher while fT4 and TSH were both lower in RTA-injured dogs than in dogs affected by other conditions. Furthermore low fT4 and tT4, and a high UCCR could be useful prognostic factors in dogs affected by RTA trauma.

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.

Clinicopathologic abnormalities associated with increased animal triage trauma score in cats with bite wound injuries: 43 cases (1998-2009)

OBJECTIVE

To document the clinical and clinicopathologic changes in cats presenting with trauma from bite wounds, identify common abnormalities associated with bite wounds, and to determine whether the calculated animal trauma triage (ATT) score is related to any clinicopathologic abnormalities.

DESIGN

Retrospective descriptive study.

SETTING

University veterinary teaching hospital.

ANIMALS

Forty-three client-owned cats that presented for bite wounds to a large, urban, veterinary hospital between 1998 and 2009.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Pertinent history, physical examination findings, results of biochemical testing, and outcome were extracted from medical records. Animal triage trauma score was calculated based on the physical examination at presentation in cats with adequate available information. Patients were classified as having either a low (<5) ATT (n = 20) or a high (≥5) ATT (n = 23) score. Male cats were overrepresented (65.1%), and a majority of cats had outdoor access (53.4%). Low venous blood pH (P = 0.047), high plasma lactate concentration (P = 0.018), and low ionized calcium concentration (P = 0.004) were associated with higher ATT scores.

CONCLUSIONS

There is a significant association between low venous blood pH, high plasma lactate concentration, and low ionized calcium concentration and higher ATT scores at presentation in cats suffering from bite wounds. Early recognition of these abnormalities may help to identify more severely injured patients.

Prospective evaluation of the acute patient physiologic and laboratory evaluation score and an extended clinicopathological profile in dogs with systemic inflammatory response syndrome

OBJECTIVE

To investigate the prognostic value of the acute patient physiologic and laboratory evaluation (APPLE) score and relevant clinicopathological markers in dogs with systemic inflammatory response syndrome (SIRS).

DESIGN

Prospective observational cohort study.

SETTING

Veterinary teaching hospital.

ANIMALS

Thirty-three dogs with SIRS admitted to the intensive care unit (ICU) were compared to 35 healthy control dogs. Dogs with SIRS were divided into septic (n = 20) and nonseptic (n = 13) etiologies and as survivors (alive to discharge, n = 22) and nonsurvivors (n = 11: died, n = 6, or humanely euthanized, n = 5).

MEASUREMENTS AND MAIN RESULTS

For all dogs, physiological and laboratory parameters were prospectively collected for the calculation of the APPLE fast score. No difference between septic and nonseptic SIRS dogs was detected for any parameter evaluated. Survivors had significantly higher total protein, albumin concentrations, antithrombin activity (ATA), and base excess (BE), as well as significantly lower lactate, urea, creatinine concentrations, urinary protein to creatinine ratio and APPLE fast score compared to nonsurvivors. Higher values of creatinine, lactate, anion gap, alanine transaminase (ALT), and APPLE fast score were significantly associated with an increased risk of death in SIRS dogs, while higher values of total protein, albumin, ATA, and BE were associated with a significantly reduced risk of mortality. When a multivariate binary logistic regression analysis was performed, the APPLE fast score was the only significant parameter retained.

CONCLUSIONS

The determination of the APPLE fast score in clinical setting, as well as the measurement of APP, ATA, lactate, BE, anion gap, ALT, urinary proteins, and electrolytes may be beneficial for a better assessment of dogs with SIRS. Identified parameters were significantly related with the presence of SIRS and their evaluation should be considered for the assessment of disease severity, and guidance of the decision-making process in critically ill dogs.

Hypocalcemia of critical illness in dogs and cats

Hypocalcemia occurs in critically ill dogs and cats and is associated with medications, treatments, and underlying diseases such as acute kidney disease, pancreatitis, parathyroid disease, sepsis, and trauma. Possible underlying mechanisms include hypovitaminosis D, acquired or relative hypoparathyroidism, hypomagnesemia, and alterations in the ionized fraction of calcium caused by changes in chelated or protein-bound calcium. If severe or acute, hypocalcemia can cause obvious clinical signs related to muscle or neurologic hyperexcitability or more subtle signs of cardiovascular dysfunction. Emergency treatment with calcium gluconate administration is recommended when clinical signs are present or if there is moderate to severe ionized hypocalcemia.

Acute management of calcium disorders

Acute management of hypercalcemia and hypocalcemia is an important part of small-animal emergency practice. In addition to hypercalcemia of malignancy and hyperparathyroidism, vitamin D toxicosis is becoming more common in companion animals as new and improved rodenticides and human pharmaceutical preparations (vitamin D analog skin creams) become more available. This article provides complete details regarding the emergency management of life-threatening hypercalcemia with focus on vitamin D intoxication. At the other end of the spectrum, hypocalcemic emergencies, such as periparturient hypocalcemia (eclampsia), may be less common but are often life threatening. This article contains guidelines for the emergency management of hypocalcemia. In summary, the urgent care of calcium disorders in small animals is reviewed.