Search Results
, repeatability of results, 11 and accuracy of the blood pressure monitor used. There are 2 noninvasive methods for the measurement of arterial blood pressure in dogs, namely the use of Doppler ultrasonography or OBPMs. Oscillometric blood pressure assessments
size in dogs with Cushing's disease . J Vet Intern Med 2005 ; 19 : 23 – 28 . 10.1111/j.1939-1676.2005.tb02653.x 29. Stepien RL Rapoport GS Henik RA , et al . Comparative diagnostic test characteristics of oscillometric and Doppler
SUMMARY
Objective
To determine reliability of noninvasive methods of arterial oxyhemoglobin saturation (SpO2 ), end-tidal CO2 concentration (PEtCO2 and blood pressure (BP) determination during periods of hypoxemia and systemic arterial BP perturbations.
Animals
7 healthy, conditioned dogs weighing 19 to 22 kg.
Procedure
3 pulse oximeters, 2 capnometers, and 2 oscillometric BP monitors were used to measure oxygen-carrying capacity of the blood, heart rate, ventilatory status and arterial BP changes during hypoxemia, and altered arterial BP. Pulse oximeter-derived SpO2 and PEtCO2 were determined during rapidly induced plateaus of hypoxia (decreased fractional inspired oxygen concentration [FiO2 ) and altered systemic arterial BP. A lead-II ECG was used to monitor heart rate.
Results
Pulse oximetry provided an accurate assessment of fractional oxyhemoglobin saturation (SaO2 ) at SpO2 > 70%. As SaO2 decreased from 70%, the magnitude of the SpO2 error increased (20% error at SpO2 < 30%). The PEtCO2 was accurate at PaCO2 , ranging from 30 to 55 ± 5 mm of Hg under all experimental conditions. When PaCO2 was > 55 mm of Hg, both capnometers produced values that were as much as 20 mm of Hg less than the corresponding PaCO2 . Mean BP was least dependent on pulse wave quality, consistently underestimating mean arterial BP by approximately 10 mm of Hg.
Conclusions and Clinical Relevance
The pulse oximeters tested provided an accurate estimation of SaO2 at SpO2 > 70%. A PEtCO2 value > 55 mm of Hg may represent hypercapnia that is more profound than indicated. Systolic BP determinations were most accurate during hypotensive states and least accurate during hypertension. Diastolic BP measurements were generally more accurate during hypertension than normotension. Accuracy is not appreciably affected by hypotension resulting from vasodilation or blood loss. The tendency to underestimate systemic arterial BP should not interfere with trend detection during unstable clinical conditions. (Am J Vet Res 1998;59:205–212)
immobile. Indirect methods offer a more user-friendly solution but have limitations, namely their accuracy and/or precision. 4 – 6 The oscillometric method is widely used to assess ABP in several veterinary species, but information on its performance in
SUMMARY
Two digital oscillometric human blood pressure measuring devices were modified and evaluated as blood pressure monitors in 12 healthy anesthetized dogs. Direct arterial pressures were measured via cannulation of the dorsal pedal artery and were correlated with indirect measurements through an inflatable cuff placed over the dorsal pedal artery below the hock joint of the contralateral limb. Direct and indirect measurements were compared for systolic, diastolic, and calculated mean arterial pressures. Blood pressure ranges between 215/145 mm of Hg and 65/30 mm of Hg were obtained, using combinations of halothane, phenylephrine, calcium, and iv administered fluids. Machine A was found to be insufficient for clinical application, on the basis of correlation coefficients between direct and indirect pressures of 0.78, 0.65, and 0.74 for systolic, diastolic, and mean arterial pressures, respectively. Higher correlation coefficients between direct and indirect pressures (0.77, 0.87, and 0.87, respectively) were obtained with machine B. The results of the study reported here suggest machine B may be an effective blood pressure monitoring device in anesthetized dogs.
dogs, 15 and other companion animals, 16 – 18 to our knowledge, agreement between direct and indirect BP measurements has not been evaluated in chimpanzees. To use oscillometry to measure BP and apply oscillometric reference intervals for the
vaporizer was turned off. After extubation, 0.3 mg/kg, IV methadone was administered and dogs were moved to individual kennels. They were further monitored using HR, oscillometric blood pressure, respiratory rate and pattern, body temperature, demeanor
addition to respiratory rate. Furthermore, the current study did not evaluate blood pressure throughout the anesthetic period. A previous study 5 evaluating isoflurane and dexmedetomidine-ketamine-midazolam recorded indirect oscillometric blood pressure
limits of available equipment. Oscillometric blood pressure monitoring has been investigated in boids and iguanas but was not an accurate substitute for direct measurements. 37 , 38 Direct blood pressure monitoring has not previously been reported in
; 61 ( 5 ): 481 – 498 . 35. Bosiack AP , Mann FA , Dodam JR , Wagner-Mann CC , Branson KR . Comparison of ultrasonic Doppler flow monitor, oscillometric, and direct arterial blood pressure measurements in ill dogs . J Vet Emerg Crit