Monthly Journal Round-Up - April 2018

Thanks as always to Lara Brunori DVM CertAVP MRCVS

Clinical studies:

Prospective:

  • Bhalla, R.J. et al. (2018) ‘Comparison of intramuscular butorphanol and buprenorphine combined with dexmedetomidine for sedation in cats’. Journal of Feline Medicine and Surgery, 20(4), pp.325-331
  • Sylvane, B. et al. (2018) ‘Effect of cross-match on packed cell volume after transfusion of packed red blood cells in transfusion-naïve anemic cats’. Journal of Veterinary Internal Medicine, doi: 10.1111/jvim.15120 (Early view)
  • Ateca, L.B. et al (2018) ‘Evaluation of the relationship between peripheral pulse palpation and Doppler systolic blood pressure in dogs presenting to an emergency service’. Journal of Veterinary Emergency and Critical Care, doi: 10.1111/vec.12718 (Early view)

Retrospective:

  • Lux, C.N. et al. (2018) ‘Perioperative mortality rate and risk factors for death in dogs undergoing surgery for treatment of thoracic trauma: 157 cases (1990-2014)’. Journal of the American Veterinary Medical Association, 252(9), pp.1090-1097. 
  • Gremillion, C.L. et al. (2018) ‘Radiographic findings and clinical factors in dogs with surgically confirmed or presumed colonic torsion’. Veterinary Radiology & Ultrasound, doi: 10.1111/vru.12595 (Early view)

Observational:

  • Ash, K. et al. (2018) ‘Performance evaluation and validation of the animal trauma triage score and modified Glasgow Coma Scale with suggested category adjustment in dogs: A VetCOT registry study’. Journal of Veterinary Emergency and Critical Care, doi: 10.1111/vec.12717 (Early view)
  • Reminga, C.L. et al. (2018) ‘Evaluation of the placement and maintenance of central venous jugular catheters in critically ill dogs and cats’. Journal of Veterinary Emergency and Critical Care, doi: 10.1111/vec.12714 (Early view) 

Case report:

  • Scagnelli, A.M. et al. (2018) ‘Effects of therapeutic plasma exchange on serum immunoglobulin concentrations in a dog with refractory immune-mediated hemolytic anemia’. Journal of the American Veterinary Medical Association, 252(9), pp. 1097-1108
  • Ueda, Y. Et al. (2018) ‘Severe lactic acidosis and hypoglycemia due to acute metformin intoxication in a dog’. Journal of Veterinary Emergency and Critical Care, doi: 10.1111/vec.12711 (Early view)

For a copy of any of the papers mentioned in this post (personal education purposes only), please email lara.brunori@gmail.com.

Pick of the Month

‘Evaluation of the relationship between peripheral pulse palpation and Doppler systolic blood pressure in dogs presenting to an emergency service’
Ateca, L.B. et al. (2018) Journal of Emergency and Critical Care, doi: 10.111/vec.12718

Peripheral pulse palpation is considered a key parameter of the emergency patient’s triage. Its evaluation is relevant for the identification of cardiovascular abnormalities like hypotension, dysrhythmias, hyperdynamic states, decreased cardiac output and peripheral vasoconstriction. 

Pulse quality is closely related to stroke volume, arterial wall compliance and intrathoracic pressure and it is determined by the difference between systolic and diastolic blood pressure. It is, therefore, a common assumption that a strong peripheral pulse is indicative of a normal/high systolic blood pressure, while a weak one represents a low systolic blood pressure or an arterial clot. 

However, recent publications in the human medical literature are no longer supportive of this assumption. Several studies demonstrated that measured arterial blood pressure was significantly lower than expected from the peripheral pulse palpation alone. 

The evidence in veterinary medicine is lacking and this prospective observational study is aimed at filling the gap evaluating the relationship between pulse quality and measured blood pressure in dogs. 

Ninety-three canine patients presented to the Emergency Department of the University of Pennsylvania Veterinary Teaching Hospital between February 2012 and December 2013 were enrolled. Inclusion criteria consisted of a complete physical examination and systemic blood pressure measurement prior to any other intervention. Dogs with suspected arterial thromboembolism were excluded from the study. 

Pulse quality of both femoral and dorsal metatarsal arteries was assessed by digital palpation. Normal pulses were defined as easily palpable, while weak or absent pulses were difficult to find or not found at all. 

Systolic blood pressure was measured via Doppler flow detector. The cuff was appropriately chosen and at least 3 measurements were obtained. The average value was then recorded.

The study’s results are clearly summarised in a table within the text (Table 1), which shows a noticeable trend for both femoral and dorsal metatarsal pulses: when quality weakens, median systolic blood pressure decreases and heart rate increases. However, the differences were only statistically significant for blood pressure values in relation to dorsal metatarsal pulse quality and for heart rate values in relation to femoral pulse quality.

Sensitivity, specificity and relative confidence interval values were calculated for the reliability of metatarsal pulse palpation to detect hypotension. A specificity of 93% vs a sensitivity of 33% was found. This means that a dog with an absent metatarsal pulse is very likely to be hypotensive, but a palpable dorsal metatarsal pulse is not enough to rule out a hypotensive status. 

This study, although generally well designed, presents several limitations. The main ones refer to the variability in the assessors’ clinical experience and the fact that they were not blinded to the systemic blood pressure measurements, nor assessed for inter-rater or intra-rater reliability. Inconsistencies in patients’ sizes and body condition scores were taken into consideration by the authors and deemed not significant in the assessment of pulse quality; nevertheless, a more homogeneous sample would have been preferable.

Ultimately the choice to use Doppler blood pressure measurement instead of more invasive methods could be justified in terms of study feasibility and patient welfare. However, it has previously been demonstrated that Doppler flow tends to underestimate systolic blood pressure values.

Conclusion:

In conclusion, this study demonstrates that an absent dorsal metatarsal pulse is very specific for hypotension and should trigger prompt interventions to re-establish adequate perfusion and blood pressure values. Nevertheless, it is not advisable to rely on a single parameter when evaluating the emergency patient’s cardiovascular status. The presence of dorsal metatarsal pulse alone does not rule out hypotension and evaluation of other indicators of poor perfusion like mucous membrane colour, capillary refill time, heart rate, mental status and systolic blood pressure should always be performed.

For a copy of any of the papers mentioned in this post (personal education purposes only), please email lara.brunori@gmail.com.

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