Can You Use A Regular Stethoscope On A Dog?
After you have located the general area, listen to the sounds with a stethoscope. When your dog is ill and has a problem with their heart rate or rhythm, a stethoscope may be useful in addition to a heart rate or rhythm monitor. A dog’s heart is frequently affected by these abnormalities, and these conditions can occasionally be caused by them.
When you wear a stethoscope, you can hear the sounds of both the lungs and the hearts of animals in their natural habitat. Because of the need for a larger bell, paediatric stethoscopes should not be used for most auscultation procedures. Ear pieces, tubing, bell, and diaphragms are the major components of a tube system (Figure 1). Each dog or cat breathes 15 to 30 times per minute. Small dogs and puppies have heart rates of 120 to 160 beats per minute. How long is a dog usually pregnant? For 58 to 68 days, the average is 58 to 68 days. Does dogs dream? If you’ve ever watched your dog twitching, chattering, or moving his or her paws while sleeping, you may be wondering if he or she is dreaming.
The sound is channeled directly into the animals chest, making it easier for a veterinarian to listen and find specific types of abnormal heart rates. This also allows the veterinarian to catch any other abnormal sounds in the chest area.
Veterinarians should always have a stethoscope on hand, but they may also want to invest in some other tools and supplies. For example, you will want an otoscope if the animal has ear problems or nasal congestion, and a rectal thermometer is necessary if there are any questions about the animals general health.
However, there are some misconceptions about whether vets can use a stethoscope on small animals, such as rabbits or hamsters. In this blog post we will discuss when a vet can use a stethoscope on small animals and what types of equipment they should have for doing so. If you need a new stethoscope for your veterinary practice, be sure to check out our Ultrascopeinventory.
A stethoscope is an important tool for any veterinarian, as it can be used to listen to the heart and lungs of both cats and dogs. Unfortunately, there are fake “high-quality brand name” stethoscopes on the market. You can find out how to recognize counterfeit stethoscopes in our blog.
It can make it much easier for an animals heart rate and breathing rates to be heard by veterinarians. This is important because some animals have faster than normal heart rates, which can be a complication for the animal.
How can I listen to my dog’s heart without a stethoscope?
It may take a little searching around to find it the first time – don’t give up! For smaller pets, placing your hand over the left side of the dog’s chest just behind the elbow also allows you to feel the heartbeat. Count the beats for 30 seconds and multiply by two to get the pulse rate in beats per minute.
How to Use a Stethoscope
Auscultation is a cheap and easy diagnostic tool available in veterinary practice. Yet it often creates uncertainty, prompting both nurses and veterinary surgeons to seek second opinions amongst colleagues. The purpose of this article is to explore the best techniques for auscultation, and discuss the different sounds that can be heard in dogs and cats when listening to the heart. The starting point of auscultation is to identify normal heart sounds. This will then help recognise abnormal heart sounds, which can then be split into loudness, timing, and point of maximal intensity.
Auscultation is a cheap and easy diagnostic tool available in every veterinary practice. Yet if we ask ourselves if it is used to its full potential, the answer is probably no. While it seems like an easy enough task to perform, it is frequently over complicated. Two things hinder auscultation technique. First, optimal listening conditions are rarely achieved; and second, cardiologists agree that recognising abnormal heart sounds, and gaining proficiency in the technique is difficult (Pedersen et al, 1999; Naylor et al, 2001; Ware, 2007).
Primarily, auscultation of the heart is used to record heart rate and rhythm, and to determine heart sounds. As with most things in life, practice is key, so that abnormal sounds can be readily distinguished from normal heart sounds. If abnormal sounds are heard, it is recommended to determine the timing of the additional sounds, the point of maximal intensity (PMI) — or where the sound is heard the loudest — and finally, the intensity or loudness of the sounds in relation to a grading system.
There are a few different types of stethoscopes available on the market (Figure 1). The better quality stethoscopes are adequate for veterinary use. Paediatric stethoscopes are not recommended for most auscultation because a larger bell is needed to maximise amplification of heart sounds. The main components are ear pieces, tubing, bell, and diaphragm (Figure 2).
The binaurals should face forward (Figure 3) and be placed snugly into the ears. It may be necessary to move the tubing to better fit the ear canal and minimise sound leakage. Sound leakage and/or environmental sounds are a common problem when attempting to detect lower heart sounds or identify heart murmurs. The diaphragm is used to hear high-pitched sounds in the lungs and heart. It is best for heart sounds one and two (S1 and S2). The bell is used for lower-pitched heart sounds and extra heart sounds (S3 and S4). Some stethoscopes do not have a separate bell and diaphragm, and so fingertip pressure should be used to distinguish high and low pitched sounds.
Consider where the auscultation is to be performed. Ideally, a quiet room and gentle handling is recommended, so as not to excite or distress the patient. Panting dogs can be a problem; gentle closing of the mouth can allow a few seconds of undisturbed auscultation. Sometimes cats may purr, which can make auscultation impossible. Holding a finger across the nose may stop purring for a moment, or turning on a tap near to the cat may provide some distraction. If the owner happens to be present during auscultation, it may need to be explained that silence is required for optimal auscultation. Owners quite often like to talk during quiet periods.
First, it is important to know what is expected to be heard. There are two normal heart sounds in the dog and cat:
S1 is a louder, longer, and duller sound than S2. It is best heard in thin and young animals, or those with high sympathetic tone, and those with tachycardia, mitral regurgitation, systemic hypertension, or anaemia. S2 is a shorter higher pitched sound, which is loudest over the pulmonic and aortic areas. Any other sounds are described as additional heart sounds. These extra sounds are described by location (the PMI), timing in the cardiac cycle, and intensity of the sound (loudness). Table 1 outlines the PMI in dogs and cats.
Timing of additional heart sounds is important. Sounds heard between S1 and S2 occur during systole. This is the most common type of heart murmur recorded in small animals. Sounds heard between S2 and S1 are diastolic. Diastolic murmurs are rare in small-animal medicine. Murmurs throughout systole and diastole are called continuous murmurs. The most common cause of a continuous murmur is a patent ductus arteriosus. Distinguishing when additional heart sounds occur, will help the veterinary surgeon to focus their differential diagnosis. An approach, such as the one described below, should be followed to reliably perform auscultation:
The loudness of a heart murmur is graded between I and VI (Table 2). Grading can be useful to assess disease progression and/or severity of certain cardiac conditions, such as aortic or pulmonic stenosis or mitral regurgitation. However, it is less useful to assess myocardial disease severity. Furthermore, ventricular septal defects will give a louder sound when the hole is smaller because of the higher pressure across the hole. Therefore, grade does not always indicate disease severity.
It is also important to remember that veterinary professionals will not always agree on the presence or loudness of a murmur. Pedersen et al (1999) conducted a study evaluating different people and their auscultation. The study used dogs diagnosed with mitral valve disease, and they found that interobserver agreement on presence and absence of mildly-diseased dogs varied between 63–88%. In a similar study, Höglund et al (2004) showed high interobserver variance in dogs with aortic stenosis. Another study looking at the comparison of cat cardiac auscultation, showed only moderate interobserver agreement (Wagner et al, 2010).
A murmur can be best described as an abnormal heart sound of prolonged duration (Ware, 2007). Blood flow normally passes through blood vessels and the heart with minimal turbulence, which does not cause a murmur. A murmur arises from a vibration of structures within the heart, created by high velocity, abnormal blood flow, turbulence or reduced blood viscosity. Heart murmurs can occur without the presence of heart disease. Innocent or physiological murmurs can be quite normal for puppies and kittens, and disappear by the age of 6 months. These murmurs are usually left sided and between grades I–III/VI. Innocent murmurs can still be present in adult cats and dogs, but if no disease is suspected, no treatment is required.
Also, in cases of severe anaemia a heart murmur can be caused by low viscosity of the blood. When the anaemia is corrected, the murmur can disappear. Heart murmurs caused by heart disease are seen when there is an obstruction to blood flow, seen with aortic stenosis, or valvular incompetence such as mitral valve disease. For a summary of heart murmur causes see Table 3.
Occasionally, it is possible to hear other heart sounds. These sounds, either an S3 or S4, are known as gallop sounds. They are lower pitched than the S2 sound and, when heard, can sound like a galloping horse. They are both heard in diastole; distinguishing one from the other is very difficult, and requires some experience and practice. An S3 sound occurs because of ventricular dilation and myocardial failure. It can sometimes be heard in dilated cardiomyopathy, or advanced valvular heart disease. An S4 sound is associated with atrial contraction in dogs and cats that have abnormal ventricular relaxation and stiffness. In cats, it can be heard with advanced hyperthyroidism or hypertrophic cardiomyopathy. Sometimes, it can be a transient finding in older, stressed, or anaemic cats.