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VetVine Client Care

Posted On Jun 23, 2025

Updated On Jul 01, 2025

Shock: Pulse Quality And Blood Pressure In Cats

Emergency & Critical Care

The triage evaluation of patients is very important and key to identifying life-threatening conditions. Shock - one life-threatening condition - can develop due to abnormalities in tissue perfusion. Poor tissue perfusion can lead to decreased oxygen delivery to organs and ultimately result in organ failure. If the patient is left untreated, they may die. Therefore, assessment of tissue perfusion is one of the core tenets of critical care medicine.

Some of the parameters we assess to identify abnormalities in blood flow (hypotension) and tissue perfusion include mucous membrane color, capillary refill time, and heart rate. Interpreting the heart rate in cats can be a bit of a challenge because cats with perfusion abnormalities / shock can become either tachycardic or bradycardic. Bradycardia has been reported as one sign of shock in cats. Respiratory rate, mentation, and pulses are also part of our assessment. When palpating peripheral pulses we can also assess the temperature of the extremities. A relatively "cold" extremity can be a sign of poor blood flow to the limb. All of these vital signs should be considered together when assessing tissue perfusion. 

We don’t, however, rely solely on those physical findings; systolic blood pressure measurements are performed to assess for hypotension. The gold standard for assessing systolic blood pressure is invasive and impractical in a triage situation. Direct arterial pressure measurements require arterial catheterization and this can be challenging - especially in cats. In the emergency practice setting, Doppler blood pressure measurements are typically assessed.

With regard to peripheral pulse palpation, it's important to remember that what we are detecting is the difference between the systolic and diastolic blood pressure of the patient. This difference (pulse pressure) depends on stroke volume and arterial elasticity. Pulse pressure can be affected by volume status, low cardiac output, or vasodilatory states like sepsis or SIRS. Other factors can also influence pulse pressure. In human medicine, peripheral pulse palpation has been studied as a method to assess circulatory status and predict hypotension. These studies have found it to be unreliable, with a tendency to overestimate systolic blood pressure.

Pulse palpation is commonly performed in veterinary medicine and it's not uncommon for inexperienced professionals to have difficulty palpating peripheral pulses in cats (practice tip: in obese or fractious cats, it may be easier to palpate metatarsal pulses than femoral ones). Experienced clinicians can often detect a difference in pulse quality between metatarsal and femoral pulses in both dogs and cats. Pulse palpation has been suggested to offer objective insight into an animal’s blood pressure. Anecdotal statements in the literature have suggested that when the systolic blood pressure is above 90 mmHg, both femoral and dorsal metatarsal pulses should be palpable. If neither is palpable, it may suggest a blood pressure below 60 mmHg.

A scientific study was eventually undertaken to assess whether peripheral pulse palpation correlated with systolic blood pressure measurements in cats. Their hypothesis was that digital palpation of peripheral pulse quality could accurately detect hypotension in cats. They wanted to investigate the anecdotal claim that cats would not have palpable pedal pulses if their systolic blood pressure dropped below 90 mmHg. This was a prospective, observational study conducted in the emergency service at the University of Pennsylvania. It involved 102 cats that had presented to the emergency service due to owner concerns about illness.

Cats with suspected aortic thromboembolism - which could affect blood flow to the pelvic limbs and compromise Doppler blood pressure readings - were excluded. A physical exam was performed on each patient and clinicians were asked to record perfusion parameters and grade pulses as strong, moderate, poor, or absent — assessing both femoral and dorsal metatarsal pulses.

Following the physical exam, blood pressure was measured using the Doppler technique. Blood pressure was taken on either a forelimb or hind limb, with several measurements averaged. Standard technique was used: clipping hair, measuring limb circumference for appropriate cuff size, applying gel, and using a 9.5 MHz probe.

For study purposes, hypotension was defined as a systolic blood pressure <90 mmHg. In cases where blood pressure could not be measured, a value of 30 mmHg was assigned for statistical analysis.

The study population consisted mostly of domestic shorthair cats, with a few domestic longhairs and three purebreds (two Persians, one Devon Rex). The median age was 9.5 years and the median weight was 5 kg [range 1.37 kg to 8 kg].

Cats presented to the emergency service with a variety of diseases including diabetic ketoacidosis, primary gastrointestinal disease, primarily renal disease, lower urinary tract disease — either urethral obstruction or non-obstructive lower urinary tract disease — and cancer. There were also cats with various other problems including trauma, anemia, sepsis, heart disease, and primary neurologic disease. They had a category of “other,” which included cats with respiratory problems. If a clinician could not determine the problem due to an owner declining a workup, the cat was also categorized as “other.” 

The median systolic blood pressure for all cats was 92.5 mmHg, but they did have a large range — from 30 mmHg (cats that had an undetectable Doppler blood pressure measurement were assigned 30) and up to 240 mmHg (hypertension).

Approximately 60% of the cats were considered to have a normal or high systolic blood pressure (greater than 90 mmHg), and about 40% of cats were considered to be hypotensive based on their Doppler blood pressure measurement (systolic blood pressure less than 90 mmHg). The range in these hypotensive cats was 30 mmHg at the low end and up to 85 mmHg at the high end.

Looking closer at the pulse quality in the hypotensive cats, 15 of those cats had absent metatarsal pulses and either absent or poor femoral pulses. Two cats had both poor metatarsal pulses and poor femoral pulses.

Regarding femoral pulse quality:

  • 25% of cats were considered to have strong pulses
  • 25% of cats had moderate pulses
  • 38% of cats had poor pulses
  • 8% of cats had absent femoral pulse quality


Regarding assessment of their metatarsal pulse quality:

  • 26% had strong metatarsal pulses
  • 20% had moderate metatarsal pulses
  • 26% had poor metatarsal pulses
  • 26% had absent metatarsal pulses


Looking closer at the femoral pulse quality of the 23 cats with absent metatarsal pulses:

  • 8 cats also had absent femoral pulses
    • The median systolic blood pressure in these 8 cats was 30 mmHg (assigned value) [range: 30 mmHg to 105 mmHg]

  • The remaining 15 cats with absent metatarsal pulses had poor femoral pulses
    • The median systolic blood pressure in this group was 30 mmHg [range of 30 mmHg to 120 mmHg]


When they evaluated the relationship of pulse palpation with systolic blood pressure — specifically looking at femoral pulses — they found that digital palpation was good for predicting the Doppler blood pressure. The systolic blood pressure for each category of pulse quality was significantly different.

The blood pressure for a cat with strong femoral pulses was significantly different compared to cats with moderate, poor, or absent pulses. They found that clinicians were actually pretty good at categorizing the pulses, and when they are "strong," that correlates with a better systolic blood pressure. Cats thought to have absent femoral pulses tended to have a low systolic blood pressure.

Looking at metatarsal pulses and their relationship with systolic blood pressure they found that only descriptors of “strong” or “absent” were correlated with Doppler blood pressure measurement. This makes sense because the difference between “moderate” and “poor” pulses is pretty subjective — especially when you're talking about a small blood vessel.

They further analyzed the relationship between absent metatarsal pulses and systolic blood pressure. They grouped cats into those with absent pulses and those with present pulses (grouping poor, moderate, and strong together as “present”). The analysis showed that if a cat had absent metatarsal pulses, this correctly identified a blood pressure ≤75 mmHg 84% of the time. Absent metatarsal pulses were both a sensitive and specific test for diagnosing hypotension (blood pressure <75 mmHg).

The findings of this study (a big take-home message) contradict previous anecdotal statements that metatarsal pulses aren't palpable when systolic blood pressure is <90 mmHg. They did have a fair number of cats with palpable dorsal metatarsal pulses even when their blood pressure was <90 mmHg. Therefore, clinicians cannot rely solely on peripheral pulse palpation to detect hypotension.

The conclusion of their study ... when assessing patients (in this case, cats) for abnormalities in tissue perfusion, evaluation should include vital signs and other perfusion parameters such as capillary refill time, heart rate, respiratory rate, body temperature, mucous membrane color, and pulse quality.

They used a scoring system to evaluate pulse quality (strong to absent), and the results suggest that an “absent” pulse is the most important indicator. If a dorsal metatarsal pulse cannot be palpated in a cat, this is very suggestive of hypotension. Feeling for both femoral and metatarsal pulses should be part of every triage exam. It is rare for a cat to lose femoral pulses; the first thing to go with progressive hypotension is the metatarsal pulse. Its quality will decline sooner than the femoral pulse.

Pulse palpation is highly subjective and there was significant overlap between systolic blood pressures across the pulse quality categories. Therefore, just feeling pulses — whether femoral or metatarsal — should not be used alone and should not replace systolic blood pressure measurement.

These cats were not allowed to acclimate to the hospital environment and some cats may have been stressed (and hypertensive). There were cats categorized as having weak or poor femoral pulses that did have high blood pressure. Anyone who has been practicing for a while has probably experienced hypertensive patients with "poor-feeling" pulses. One takeaway from this study is that when evaluating tissue perfusion and blood flow abnormalities in the emergency setting, frequent reassessments should be performed. This includes feeling both femoral and metatarsal pulses and comparing their quality and monitoring response to interventions like fluids. Systolic blood pressure measurements should also be rechecked to confirm findings.

Numerous clinicians performed pulse quality assessments in this study. Despite the "subjectivity" that this introduced, they were pretty good at physical exams. Consistently, strong pulses generally meant higher systolic BP and absent pulses strongly correlated with low systolic BP (<75 mmHg). As previously mentioned, there was overlap between pulse quality groups and individual variability existed. For example, a cat in the “strong” group could still have a low blood pressure (outlier). Because of this subjectivity, the authors advocate for objective BP measurement.

Another key point is that it may not even matter what the actual blood pressure measurement is if tissue perfusion parameters and pulse quality suggest hypoperfusion. In early compensatory shock blood pressure may be normal, but subtle pulse differences can signal abnormal intravascular volume status and the need for intervention — even if systolic BP appears normal. Clinicians need to integrate all findings to assess whether perfusion is affected and whether intervention is indicated.

If a cat presents unresponsive and in cardiopulmonary arrest, the femoral pulse shoul be assessed first. It’s rare to lose femoral pulses except in cases of severe hypotension. In those cases, if you're checking for a pulse to determine whether to initiate CPR, use the femoral artery. If no femoral pulse is felt within 10 seconds, begin chest compressions and intubation. If the cat is alive, it will resist, at which point you reassess.

[1] Prediction of systolic blood pressure using peripheral pulse palpation in cats. J Vet Emerg Crit Care. 2016 Jan-Feb;26(1):52-7. doi: 10.1111.vec.12418