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Physical Examination of the Cat
Symposium on Physical Diagnosis
Physical Examination of the Cat
Barbara Sydney Stein, D.V.M.*
Physical examination of the cat must be accompanied by an accurate relevant medical history because it is the symbiotic relationship of the two that often suggests a diagnosis. The veterinarian must be as willing and able to take the time to obtain the anamnesis as to perform a thorough physical examination. Although technicians may obtain brief information as to the type of problem for which a patient is presented, it is the veterinarian who should delve further into the presenting complaint. The initial patient information data base· may often be obtained from a thorough form that clients are asked to complete on their first visit. These forms may include the following information: vaccination status, previous illnesses and surgeries, diet, drug idiosyncrasies, and present medication being given. This information is then transferred to the cat' s permanent record. The cat' s weight should be recorded before the animal is examined. Because of an owner's anxiety, it is most direct to first examine the cat for the problem for which it is presented. Once the area of initial concern has been acknowledged, the remainder of the normal examination should take place. Examination of the cat should be performed in a quiet, well lit environment. If the cat has been brought in a carrier, the animal should remain in it until the time of examination. Likewise, an unrestrained cat should be kept in the owner's arms. If cats are allowed to roam the exam room prior to evaluation, they may become aggravated or hostile due to residual animal odors and pheromones. To minimize distractions, preferably only one or two clients should remain in the exam room with the cat and veterinarian. Unless the cat is known to be very difficult to handle, it is best to have the owner, rather than a veterinary assistant, help restrain the cat as needed. The veterinarian's first contact with the cat is important and may well determine the ease with which the examination proceeds. Most cats will be naturally curious and advance toward an outstretched hand for initial interaction. Scratching the dorsum of the head will *Private Practitioner, Chicago, Illinois Veterinary Clinics of North America: Small Animal Practice- Vol. 11, No.3, August 1981
469
470
BARBARA SYDNEY STEIN
often establish a positive rapport between veterinarian and patient (Fig. 1). The veterinarian must remember that each cat has a different area of critical distance that can be approached only with time and gentleness. Rapid infringement upon that critical distance is often responsible for acute trauma-to the veterinarian. In some instances, the cat may act less threatened if the veterinarian is seated during the examination rather than looming tall above the patient. As the cat is placed on the exam table, obvious displays of aggressive behavior (hissing, growling, backward positioning of the ears) require that time be allowed to pass before any handling is attempted. If the cat remains hostile, the owners should position the cat so it is facing them; the veterinarian can then attempt to scratch its head from the rear. If the cat will still not allow contact for examination, a towel or small blanket is often useful to help subdue the aggressive patient. If this fails, the cat should be sedated if examination is deemed necessary. Whatever the order of examination, it is imperative for each clinician to establish his or her own pattern and that it become a routine progression. Haphazard examination will always be deficient in some category. If the cat is calm and easily handled, the rectal temperature may be taken while gathering some pertinent medical history from the client. Aggressive cats or those that are difficult to handle may best be restrained and soothed for a few minutes in a blanket held by the
*
Figure 1. Scratching the dorsum of the cat' s head during examination or while giving injections is often the best form of restraint or distraction.
PHYSICAL EXAMINATION OF THE CAT
471
owner before attempting to record body temperature. If the cat strongly resists having its temperature taken, the rest of the examination should proceed first. A thin' rectal or oral thermometer should be lubricated first before insertion. With the tail slightly elevated with one hand, the thermometer is gently inserted using a rolling motion. The clinician should hold on to the thermometer at all times to prevent accidental breakage. At the time the temperature is taken, the veterinarian should also note if the rectal area is clean or soiled from diarrhea or matting and whether the anal sacs are distended. The perineum is observed for the presence of tapeworms. Before examining specific areas of the body, the overall appearance of the cat should be determined. Respirations, head and body positioning, and degree of alertness may all change once the examination begins. The hair coat should be clean and shiny; shedding may increase at the veterinarian's office due to stress and fear. The body musculature should be firm, prominent, and sinewy. The presence of any body odor, the state of hydration, and degree of body fat are all assessments readily made. The entire body should be gently and quickly palpated externally for the presence of any masses or painful areas, as well as for signs of external parasitism. The limbs and tail are examined for evidence of swelling, bite wounds, and potential abscesses. The feet and nails should not be overlooked; it may be preventive medicine for the veterinarian to trim the nails of some patients early in the examination process! The external lymph nodes, especially mandibular and popliteal, should be evaluated. At the time of initial examination of kittens, the possibility of an umbilical hernia should be remembered, along with the many other common congenital defects. In cats of average weight, the inguinal fat pad may be markedly pronounced; owners often express concern that this represents an inguinal hernia rather than normal anatomy. Following routine examination and palpation, the cat should be observed for locomotion and possible gait abnormalities. HEAD AND NECK
Oral Cavity The single most neglected area of examination in the cat is the oral cavity. In some respects, this particular area of examination may reveal more signs of disease than any other. The cat' s mouth is easily opened for examination by placing one hand around the head and extending the head backward to allow the mandible to fall open (Fig. 2). With the mouth held open, quick but thorough examination of the entire oral cavity is possible. The normal cat' s tonsils are not visible on routine oral exam.
472
BARBARA SYDNEY STEIN
Figure 2. To examin~ the area under the eat's tongue, the thumb is placed in the intermandibular space and; gentle upward pressure applied.
A foul mouth odor is usually attributable to dental problems. Calculus formation, gingivitis, periodontal disease, root abscesses, broken teeth, and caries are all common e ntities in the cat which require a thorough dental evaluation under anesthesia. Seemingly hyperplastic gingival tissue may actually be covering deep caries on the buccal surface of a tooth. As in any species, dental prophylaxis is to be strongly encouraged before major dentistry is required. Examination of the sublingual area is accomplished by tilting the head upward with one hand and placing the opposite thumb in the intermandibular space (see Fig. 2). Ventral tongue tumors and foreign bodies (strings) retained by the frenulum are not uncommon~ Every vomiting cat should be examined for possible string foreign body originating under the tongue. By lifting the upper lip, the mucous membranes may be assesse d for color, refill, and moisture. Anemia, cyanosis, and icterus are ofte n readily detected by changes in gingival color. Similarly, dry mucous membranes indicate varying degrees of dehydration. Abnormal capillary refill time may suggest anemia or other circulatory defects (for example, cardiac distress). The chin should be examined for the presence of comedones or mandibular acne and pyoderma. Eye The overall appearance of the eyes should be noted, including the presence of any discharges, squinting, or asymmetry. Se vere weight
473
PHYSICAL EXAMINATION OF THE CAT
loss or dehydration will give the eyes a sunken appearance. In contrast, acute glaucoma or retrobulbar abscess or neoplasm may result in a swollen, enlarged globe (exophthalmos). Eyelid abnormalities such as ectropion (rare in the cat) and entropion are readily apparent. Detection of trichiasis or distichiasis, however, may require very careful examination with magnification. The normal sclera is predominantly white and relatively avascular. The conjunctiva is pink and moist but void of any discharge. The nictitating membrane is only slightly visible at the medial canthus. The size, shape, and symmetry of the pupil and its rapid response to light (both direct and consensual) is easily determined with a penlight. Any opacity of the lens should be noted. A clear anterior chamber permits easy visualization of the iris. Fundic evaluation is often not part of the routine physical examination. It is especially important, however, to perform a fundic examination in any instance when systemic or neurologic disease is suspected. Likewise, any evidence of external ocular disease suggests a complete ophthalmic exam. Routine fundic examination of the normal cat will h elp prepare the novice for recognizing abnormal findings and is strongly encouraged. Ear All cats have a normal area of preauricular alopecia, which is especially noticeable in cats with dark coats (Fig. 3). The entire area between the eye and the ear may be sparsely covered with hair.
*
Figure 3. Note normal preauricular alopecia, which is especially prominent in cats with dark coats.
474
BARBARA SYDNEY STEIN
The pinnae of the ear should be examined for alopecia or scaling caused by fungal infection. Bite wounds from other cats or self-trauma due to otitis externa may result in hematoma of the pinna. In sunny climates, severe sunburn and primary neoplasms of the pinna are known to occur. Thickening of the ear edges and crusting over the dorsum of the head is characteristic of Notoedres cati infection. The internal ear canal is best examined by gently positioning the pinna up, out, and backward (posterior) to straighten the vertical canal before inserting the otoscope. The normal ear canal has no foul odor, virtually no discharge, and is light pink in color. The tympanic membrane is translucent, glistening, and creamy white in color. If the canal is filled with debris, careful cleaning should precede the use of the otoscope so that de bris is not accide ntally we dged more deeply into the canal. Otodectes cynotis infection is the most common ear disorder in the cat; therefore, any debris in the cat' s ear should be microscopically examined for evidence of mite infestation. Chronic otitis may also be due to bacterial or fungal infections, seborrhea, or the presence of a foreign body. It is not uncommon to find small tumors d eep in the horizontal ear canal of cats with chronic otitis. The normal middle and inner ear can not be examined in a healthy cat. Only if disease exists are signs such as head tilt, ataxia, and nystagmus readily noticed. Hearing defects are probably best discovered b y the owner although a thorough ear examination should still be performed. Most blue-eyed white cats are genetically predisposed to deafne ss. Neck Lateral and dorsoventral neck movement should be well tolerated by the cat. Both mandibular lymph nodes and the salivary glands should be palpated for size and uniformity. The thyroid glands are not palpable in the normal cat; their presence may be noted in the hyperthyroid animal. Palpation of the larynx and trachea should not elicit a cough or be rese nted b y the cat.
THORAX
The initial thoracic examination should include observation, auscultation, palpation, and if necessary, p e rcussion. Because of the cat' s initial excitement at being at the veterinarian's office, both the respiratory and cardiac rates are usually elevated above normal. However, obse rvation of the cat' s pattern of breathing will immediately indicate if any severe dyspnea is pre se nt; nostril flare, abdominal breathing, or inspiratory or expiratory noise are all indications of distress. Similarly, the clinician may assess cardiovascular distress b y observing the presence of a jugular pulse .
PHYSICAL EXAMINATION OF THE CAT
475
Auscultation must be performed in a quiet room, preferably with a pediatric stethoscope. The heart rate and rhythm are easily determined. The heart should be auscultated on both sides of the chest as well as ventrally. At the same time the heart is auscultated, the femoral pulse should be determined. In addition to heart murmurs caused by congenital abnormalities, it is common to auscultate a rapid heart murmur in the anemic cat. When possible, anatomic localization of heart murmurs may help identify their origin. Due to the recent increased recognition of several forms of feline cardiomyopathy, it is no longer unusual for a pet to be presented with severe cardiac failure; radiography and electrocardiography are also required for a complete diagnosis. Muffling of the heart sounds may be due to fluid or a solid mass near the heart and requires further radiographic interpretation. Vesicular lung sounds of the normal cat are not dramatic and may be difficult for the novice to assess. At least four sites of auscultation of the lungs should be made. A characteristic high-pitched wheeze is heard in feline bronchial asthma and some forms of chronic bronchitis. The presence of peristaltic sounds within the thorax strongly suggests a diaphragmatic hernia with small bowel protrusion into the chest or even pericardium. Harsh moist rales may indicate pneumonia or early lower respiratory tract infection. Dull, muffled sounds suggest the presence of fluid and/or a mass in the chest. Palpation of the feline thorax is often overlooked despite being a quick and informative technique. The normal anterior thorax of the cat is relatively compressible; if the thumb is placed on one side of the anterior thorax with the fingers on the opposite side, the ribs should have a "spring" resiliency and allow for moderate compression of the anterior chest (Fig. 4). In the presence of an anterior mediastinal mass (lymphosarcoma), the compression is absent and the feeling of solid tissue is distinct. The ribs should be palpated for smoothness and continuity. If free fluid or air are suspected within the thoracic cavity, digital percussion may quickly verify the abnormality. This is a diagnostic art that must be practiced on many normal animals before one is confident of detecting the change in resonance from a dull sound ventrally to a tympanic sound dorsally. Cats that are severely dyspneic are serious risks for any type of examination. It is often wise to provide oxygen via an incubator or closed cage before further stressing the animal. In the presence of severe pleural effusion, thoracocentesis should be performed as soon as the cat is stable. Minimal sedation by injection rather than inhalation is given only when needed to avoid struggling and further stress. Examination of the fluid along with radiographic findings once the chest is cleared will usually establish the diagnosis. The purring cat may make auscultation impossible . The owner should stop touching the cat as this will often stop the purring. If not,
476
*
BARBARA SYDNEY STEIN
Figure 4. Palpation of the anterior thorax for compressibility. Four fingers are on the left lateral chest wall and the thumb is on the right lateral chest wall.
the veterinarian can gently apply pressure at the larynx for a few seconds at a time to make the cat cease purring.
ABDOMEN Abdominal palpation is a practice art that is never fully mastered. However, a systematic organ-by-organ approach will usually establish an examination pattern that becomes automatic and routine. The novice should especially take every opportunity to palpate the abdomen of a sedated animal because abdominal relaxation allows even easier organ identification. The cat should be placed standing and facing the owner with the veterinarian beginning palpation from a rear approach. Just as in the dog, abdominal palpation with the right hand may be aided by encircling the upper left hindlimb with the left hand. The left thumb is placed against the femur and the four fingers grasp the medial thigh (Fig. 5). At the same time it is helpful to have the owner simply rub the dorsum of the cat' s head. If the cat is slightly difficult to handle, the veterinarian may prefer to restrain the cat' s head with the left hand during palpation. Palpation of the normal liver is prohibited by the presence of the overlying rib cage. Occasionally the sharp edges of the normal liver may be barely palpable if the cat is held upright in a standing position.
PHYSICAL EXAMINATION OF THE CAT
477
Figure 5. Palpation of the cat' s abdomen with one hand may be aided by restraining the hindlimb on the opposite side.
Only in cases of hepatomegaly is the liver more fully palpable, and then the hepatic edges are usually rounded. The empty stomach is palpable only in a thin animal, although if distended with food, it is easily palpated in the upper left abdominal quadrant. The gallbladder and pancreas are normally not palpable. Palpation of the thin-walled small intestine filling much of the mid-abdomen is usually unremarkable and easily performed. Regional or generalized thickening of any area of the small intestine is abnormal and necessitates further testing and evaluation. Distinguishing hairballs and intestinal contents from intestinal masses is usually made by being able to gently move the position of the former farther through the intestine. Normal mesenteric lymph nodes are barely palpable, but severe lymphadenopathy may be mistaken for an intestinal mass. The large intestine is often full of fecal material and, therefore, easily identified by palpation of the posterior abdomen, just ventral to the spine. Palpation of the spleen is not consistently possible. It is located on the left side of the abdomen, posterior and lateral to the stomach, and its oblong outline is smooth and firm. Often only the free distal portion is palpable on the floor of the mid-abdomen. In severe splenomegaly, however, as occurs in mast cell sarcoma, the spleen may occupy the entire ve ntral abdominal floor and seem to fill the belly.
478
BARBARA SYDNEY STEIN
Both kidneys of the cat are easily palpable, kidney bean-shaped structures located on either side of the vertebral column at approximately the level of the third to fifth lumbar vertebrae. Their outline may be padded by fat directly proportional to the weight of the cat. The right kidney is usually slightly anterior to the left kidney (1 to 2 em). Although both kidneys are more loosely attached than in the dog, the left kidney is slight more movable than the right. The kidneys should be palpated not only ~or size and shape but for smoothness of outline and absence of pain. Finding only one kidney or disproportionate size between kidneys is not rare. The next palpable portion of the urinary tract is the pear-shaped bladder, which lies between the ventral abdominal wall and the descending colon. Its size, shape, and degree of firmness obviously varies with the amount of urine contained within it. Palpation of the normal bladder should not be painful. Since most feline cystic calculi are small and flat, they are rarely palpable. The normal nongravid uterus is not palpable. Enlargement due to pregnancy or pyometra, however, makes its outline easily discernible. The distended uterus lies between the bladder and the colon and falls ventroanteriorly into the abdominal cavity. Palpation of the eat's abdomen should be performed gently and methodically. Any indication of pain dictates gently repalpating the area to see if discomfort is a consistent finding which then warrants further investigation. Ascites may be suspected if the abdominal contents appear too movable or loose within a distended abdomen. Ballottement of the abdomen may also be helpful in detecting ascites. Similarly, abdominal distention is often more apparent if the cat is placed on the floor and viewed from above. Paracentesis and fluid analysis are necessary to establish a diagnosis.
EXTERNAL GENITALIA It is imperative that the mammary glands of both male and female cats be palpated on routine examination. There are normally eight glands in both sexes. Because of the high proportion of mammary gland malignancies, all masses within or between glands should be considered suspect and immediate surgical excision and biopsy is suggested. Often early pregnancy may be confirmed not only by abdominal palpation of distinct uterine enlargements but by a change in the nipples to a pink, turgid position. The vulva of both the intact and spayed female should be free of any discharge or discoloration. The spayed female's vulva is atrophied. In the intact male, the testes lie in a horizontal position within the scrotum, which is located dorsal to the penis and ventral to the anus. If
PHYSICAL EXAMINATION OF THE CAT
479
one or both testes are absent and the cat has not been castrated, palpation of the inguinal canal may reveal their partially undescended position unless the testes are completely within the abdominal cavity. Some male cats will allow the prepuce to be withdrawn and the distal end of the penis to be examined. In the intact male, the penis is covered with minute spiny papillae that atrophy and disappear following castration. Occasionally hair rings may form at the base of the penis of a breeding tomcat, which prevents the penis from retracting back into the sheath.
CONCLUSION By themselves, an accurate medical history and thorough physical examination will often provide a diagnosis. If further diagnostic procedures are necessary, the direction and degree of these tests are dictated b y the initial examination and history. The history provides the past, the examination reveals the present, and the clinician may determine the future. Chicago Cat Clinic 5301 West Devon Avenue Chicago, Illinois 60646
Physical Examination of the Cat
Barbara Sydney Stein, D.V.M.*
Physical examination of the cat must be accompanied by an accurate relevant medical history because it is the symbiotic relationship of the two that often suggests a diagnosis. The veterinarian must be as willing and able to take the time to obtain the anamnesis as to perform a thorough physical examination. Although technicians may obtain brief information as to the type of problem for which a patient is presented, it is the veterinarian who should delve further into the presenting complaint. The initial patient information data base· may often be obtained from a thorough form that clients are asked to complete on their first visit. These forms may include the following information: vaccination status, previous illnesses and surgeries, diet, drug idiosyncrasies, and present medication being given. This information is then transferred to the cat' s permanent record. The cat' s weight should be recorded before the animal is examined. Because of an owner's anxiety, it is most direct to first examine the cat for the problem for which it is presented. Once the area of initial concern has been acknowledged, the remainder of the normal examination should take place. Examination of the cat should be performed in a quiet, well lit environment. If the cat has been brought in a carrier, the animal should remain in it until the time of examination. Likewise, an unrestrained cat should be kept in the owner's arms. If cats are allowed to roam the exam room prior to evaluation, they may become aggravated or hostile due to residual animal odors and pheromones. To minimize distractions, preferably only one or two clients should remain in the exam room with the cat and veterinarian. Unless the cat is known to be very difficult to handle, it is best to have the owner, rather than a veterinary assistant, help restrain the cat as needed. The veterinarian's first contact with the cat is important and may well determine the ease with which the examination proceeds. Most cats will be naturally curious and advance toward an outstretched hand for initial interaction. Scratching the dorsum of the head will *Private Practitioner, Chicago, Illinois Veterinary Clinics of North America: Small Animal Practice- Vol. 11, No.3, August 1981
469
470
BARBARA SYDNEY STEIN
often establish a positive rapport between veterinarian and patient (Fig. 1). The veterinarian must remember that each cat has a different area of critical distance that can be approached only with time and gentleness. Rapid infringement upon that critical distance is often responsible for acute trauma-to the veterinarian. In some instances, the cat may act less threatened if the veterinarian is seated during the examination rather than looming tall above the patient. As the cat is placed on the exam table, obvious displays of aggressive behavior (hissing, growling, backward positioning of the ears) require that time be allowed to pass before any handling is attempted. If the cat remains hostile, the owners should position the cat so it is facing them; the veterinarian can then attempt to scratch its head from the rear. If the cat will still not allow contact for examination, a towel or small blanket is often useful to help subdue the aggressive patient. If this fails, the cat should be sedated if examination is deemed necessary. Whatever the order of examination, it is imperative for each clinician to establish his or her own pattern and that it become a routine progression. Haphazard examination will always be deficient in some category. If the cat is calm and easily handled, the rectal temperature may be taken while gathering some pertinent medical history from the client. Aggressive cats or those that are difficult to handle may best be restrained and soothed for a few minutes in a blanket held by the
*
Figure 1. Scratching the dorsum of the cat' s head during examination or while giving injections is often the best form of restraint or distraction.
PHYSICAL EXAMINATION OF THE CAT
471
owner before attempting to record body temperature. If the cat strongly resists having its temperature taken, the rest of the examination should proceed first. A thin' rectal or oral thermometer should be lubricated first before insertion. With the tail slightly elevated with one hand, the thermometer is gently inserted using a rolling motion. The clinician should hold on to the thermometer at all times to prevent accidental breakage. At the time the temperature is taken, the veterinarian should also note if the rectal area is clean or soiled from diarrhea or matting and whether the anal sacs are distended. The perineum is observed for the presence of tapeworms. Before examining specific areas of the body, the overall appearance of the cat should be determined. Respirations, head and body positioning, and degree of alertness may all change once the examination begins. The hair coat should be clean and shiny; shedding may increase at the veterinarian's office due to stress and fear. The body musculature should be firm, prominent, and sinewy. The presence of any body odor, the state of hydration, and degree of body fat are all assessments readily made. The entire body should be gently and quickly palpated externally for the presence of any masses or painful areas, as well as for signs of external parasitism. The limbs and tail are examined for evidence of swelling, bite wounds, and potential abscesses. The feet and nails should not be overlooked; it may be preventive medicine for the veterinarian to trim the nails of some patients early in the examination process! The external lymph nodes, especially mandibular and popliteal, should be evaluated. At the time of initial examination of kittens, the possibility of an umbilical hernia should be remembered, along with the many other common congenital defects. In cats of average weight, the inguinal fat pad may be markedly pronounced; owners often express concern that this represents an inguinal hernia rather than normal anatomy. Following routine examination and palpation, the cat should be observed for locomotion and possible gait abnormalities. HEAD AND NECK
Oral Cavity The single most neglected area of examination in the cat is the oral cavity. In some respects, this particular area of examination may reveal more signs of disease than any other. The cat' s mouth is easily opened for examination by placing one hand around the head and extending the head backward to allow the mandible to fall open (Fig. 2). With the mouth held open, quick but thorough examination of the entire oral cavity is possible. The normal cat' s tonsils are not visible on routine oral exam.
472
BARBARA SYDNEY STEIN
Figure 2. To examin~ the area under the eat's tongue, the thumb is placed in the intermandibular space and; gentle upward pressure applied.
A foul mouth odor is usually attributable to dental problems. Calculus formation, gingivitis, periodontal disease, root abscesses, broken teeth, and caries are all common e ntities in the cat which require a thorough dental evaluation under anesthesia. Seemingly hyperplastic gingival tissue may actually be covering deep caries on the buccal surface of a tooth. As in any species, dental prophylaxis is to be strongly encouraged before major dentistry is required. Examination of the sublingual area is accomplished by tilting the head upward with one hand and placing the opposite thumb in the intermandibular space (see Fig. 2). Ventral tongue tumors and foreign bodies (strings) retained by the frenulum are not uncommon~ Every vomiting cat should be examined for possible string foreign body originating under the tongue. By lifting the upper lip, the mucous membranes may be assesse d for color, refill, and moisture. Anemia, cyanosis, and icterus are ofte n readily detected by changes in gingival color. Similarly, dry mucous membranes indicate varying degrees of dehydration. Abnormal capillary refill time may suggest anemia or other circulatory defects (for example, cardiac distress). The chin should be examined for the presence of comedones or mandibular acne and pyoderma. Eye The overall appearance of the eyes should be noted, including the presence of any discharges, squinting, or asymmetry. Se vere weight
473
PHYSICAL EXAMINATION OF THE CAT
loss or dehydration will give the eyes a sunken appearance. In contrast, acute glaucoma or retrobulbar abscess or neoplasm may result in a swollen, enlarged globe (exophthalmos). Eyelid abnormalities such as ectropion (rare in the cat) and entropion are readily apparent. Detection of trichiasis or distichiasis, however, may require very careful examination with magnification. The normal sclera is predominantly white and relatively avascular. The conjunctiva is pink and moist but void of any discharge. The nictitating membrane is only slightly visible at the medial canthus. The size, shape, and symmetry of the pupil and its rapid response to light (both direct and consensual) is easily determined with a penlight. Any opacity of the lens should be noted. A clear anterior chamber permits easy visualization of the iris. Fundic evaluation is often not part of the routine physical examination. It is especially important, however, to perform a fundic examination in any instance when systemic or neurologic disease is suspected. Likewise, any evidence of external ocular disease suggests a complete ophthalmic exam. Routine fundic examination of the normal cat will h elp prepare the novice for recognizing abnormal findings and is strongly encouraged. Ear All cats have a normal area of preauricular alopecia, which is especially noticeable in cats with dark coats (Fig. 3). The entire area between the eye and the ear may be sparsely covered with hair.
*
Figure 3. Note normal preauricular alopecia, which is especially prominent in cats with dark coats.
474
BARBARA SYDNEY STEIN
The pinnae of the ear should be examined for alopecia or scaling caused by fungal infection. Bite wounds from other cats or self-trauma due to otitis externa may result in hematoma of the pinna. In sunny climates, severe sunburn and primary neoplasms of the pinna are known to occur. Thickening of the ear edges and crusting over the dorsum of the head is characteristic of Notoedres cati infection. The internal ear canal is best examined by gently positioning the pinna up, out, and backward (posterior) to straighten the vertical canal before inserting the otoscope. The normal ear canal has no foul odor, virtually no discharge, and is light pink in color. The tympanic membrane is translucent, glistening, and creamy white in color. If the canal is filled with debris, careful cleaning should precede the use of the otoscope so that de bris is not accide ntally we dged more deeply into the canal. Otodectes cynotis infection is the most common ear disorder in the cat; therefore, any debris in the cat' s ear should be microscopically examined for evidence of mite infestation. Chronic otitis may also be due to bacterial or fungal infections, seborrhea, or the presence of a foreign body. It is not uncommon to find small tumors d eep in the horizontal ear canal of cats with chronic otitis. The normal middle and inner ear can not be examined in a healthy cat. Only if disease exists are signs such as head tilt, ataxia, and nystagmus readily noticed. Hearing defects are probably best discovered b y the owner although a thorough ear examination should still be performed. Most blue-eyed white cats are genetically predisposed to deafne ss. Neck Lateral and dorsoventral neck movement should be well tolerated by the cat. Both mandibular lymph nodes and the salivary glands should be palpated for size and uniformity. The thyroid glands are not palpable in the normal cat; their presence may be noted in the hyperthyroid animal. Palpation of the larynx and trachea should not elicit a cough or be rese nted b y the cat.
THORAX
The initial thoracic examination should include observation, auscultation, palpation, and if necessary, p e rcussion. Because of the cat' s initial excitement at being at the veterinarian's office, both the respiratory and cardiac rates are usually elevated above normal. However, obse rvation of the cat' s pattern of breathing will immediately indicate if any severe dyspnea is pre se nt; nostril flare, abdominal breathing, or inspiratory or expiratory noise are all indications of distress. Similarly, the clinician may assess cardiovascular distress b y observing the presence of a jugular pulse .
PHYSICAL EXAMINATION OF THE CAT
475
Auscultation must be performed in a quiet room, preferably with a pediatric stethoscope. The heart rate and rhythm are easily determined. The heart should be auscultated on both sides of the chest as well as ventrally. At the same time the heart is auscultated, the femoral pulse should be determined. In addition to heart murmurs caused by congenital abnormalities, it is common to auscultate a rapid heart murmur in the anemic cat. When possible, anatomic localization of heart murmurs may help identify their origin. Due to the recent increased recognition of several forms of feline cardiomyopathy, it is no longer unusual for a pet to be presented with severe cardiac failure; radiography and electrocardiography are also required for a complete diagnosis. Muffling of the heart sounds may be due to fluid or a solid mass near the heart and requires further radiographic interpretation. Vesicular lung sounds of the normal cat are not dramatic and may be difficult for the novice to assess. At least four sites of auscultation of the lungs should be made. A characteristic high-pitched wheeze is heard in feline bronchial asthma and some forms of chronic bronchitis. The presence of peristaltic sounds within the thorax strongly suggests a diaphragmatic hernia with small bowel protrusion into the chest or even pericardium. Harsh moist rales may indicate pneumonia or early lower respiratory tract infection. Dull, muffled sounds suggest the presence of fluid and/or a mass in the chest. Palpation of the feline thorax is often overlooked despite being a quick and informative technique. The normal anterior thorax of the cat is relatively compressible; if the thumb is placed on one side of the anterior thorax with the fingers on the opposite side, the ribs should have a "spring" resiliency and allow for moderate compression of the anterior chest (Fig. 4). In the presence of an anterior mediastinal mass (lymphosarcoma), the compression is absent and the feeling of solid tissue is distinct. The ribs should be palpated for smoothness and continuity. If free fluid or air are suspected within the thoracic cavity, digital percussion may quickly verify the abnormality. This is a diagnostic art that must be practiced on many normal animals before one is confident of detecting the change in resonance from a dull sound ventrally to a tympanic sound dorsally. Cats that are severely dyspneic are serious risks for any type of examination. It is often wise to provide oxygen via an incubator or closed cage before further stressing the animal. In the presence of severe pleural effusion, thoracocentesis should be performed as soon as the cat is stable. Minimal sedation by injection rather than inhalation is given only when needed to avoid struggling and further stress. Examination of the fluid along with radiographic findings once the chest is cleared will usually establish the diagnosis. The purring cat may make auscultation impossible . The owner should stop touching the cat as this will often stop the purring. If not,
476
*
BARBARA SYDNEY STEIN
Figure 4. Palpation of the anterior thorax for compressibility. Four fingers are on the left lateral chest wall and the thumb is on the right lateral chest wall.
the veterinarian can gently apply pressure at the larynx for a few seconds at a time to make the cat cease purring.
ABDOMEN Abdominal palpation is a practice art that is never fully mastered. However, a systematic organ-by-organ approach will usually establish an examination pattern that becomes automatic and routine. The novice should especially take every opportunity to palpate the abdomen of a sedated animal because abdominal relaxation allows even easier organ identification. The cat should be placed standing and facing the owner with the veterinarian beginning palpation from a rear approach. Just as in the dog, abdominal palpation with the right hand may be aided by encircling the upper left hindlimb with the left hand. The left thumb is placed against the femur and the four fingers grasp the medial thigh (Fig. 5). At the same time it is helpful to have the owner simply rub the dorsum of the cat' s head. If the cat is slightly difficult to handle, the veterinarian may prefer to restrain the cat' s head with the left hand during palpation. Palpation of the normal liver is prohibited by the presence of the overlying rib cage. Occasionally the sharp edges of the normal liver may be barely palpable if the cat is held upright in a standing position.
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Figure 5. Palpation of the cat' s abdomen with one hand may be aided by restraining the hindlimb on the opposite side.
Only in cases of hepatomegaly is the liver more fully palpable, and then the hepatic edges are usually rounded. The empty stomach is palpable only in a thin animal, although if distended with food, it is easily palpated in the upper left abdominal quadrant. The gallbladder and pancreas are normally not palpable. Palpation of the thin-walled small intestine filling much of the mid-abdomen is usually unremarkable and easily performed. Regional or generalized thickening of any area of the small intestine is abnormal and necessitates further testing and evaluation. Distinguishing hairballs and intestinal contents from intestinal masses is usually made by being able to gently move the position of the former farther through the intestine. Normal mesenteric lymph nodes are barely palpable, but severe lymphadenopathy may be mistaken for an intestinal mass. The large intestine is often full of fecal material and, therefore, easily identified by palpation of the posterior abdomen, just ventral to the spine. Palpation of the spleen is not consistently possible. It is located on the left side of the abdomen, posterior and lateral to the stomach, and its oblong outline is smooth and firm. Often only the free distal portion is palpable on the floor of the mid-abdomen. In severe splenomegaly, however, as occurs in mast cell sarcoma, the spleen may occupy the entire ve ntral abdominal floor and seem to fill the belly.
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BARBARA SYDNEY STEIN
Both kidneys of the cat are easily palpable, kidney bean-shaped structures located on either side of the vertebral column at approximately the level of the third to fifth lumbar vertebrae. Their outline may be padded by fat directly proportional to the weight of the cat. The right kidney is usually slightly anterior to the left kidney (1 to 2 em). Although both kidneys are more loosely attached than in the dog, the left kidney is slight more movable than the right. The kidneys should be palpated not only ~or size and shape but for smoothness of outline and absence of pain. Finding only one kidney or disproportionate size between kidneys is not rare. The next palpable portion of the urinary tract is the pear-shaped bladder, which lies between the ventral abdominal wall and the descending colon. Its size, shape, and degree of firmness obviously varies with the amount of urine contained within it. Palpation of the normal bladder should not be painful. Since most feline cystic calculi are small and flat, they are rarely palpable. The normal nongravid uterus is not palpable. Enlargement due to pregnancy or pyometra, however, makes its outline easily discernible. The distended uterus lies between the bladder and the colon and falls ventroanteriorly into the abdominal cavity. Palpation of the eat's abdomen should be performed gently and methodically. Any indication of pain dictates gently repalpating the area to see if discomfort is a consistent finding which then warrants further investigation. Ascites may be suspected if the abdominal contents appear too movable or loose within a distended abdomen. Ballottement of the abdomen may also be helpful in detecting ascites. Similarly, abdominal distention is often more apparent if the cat is placed on the floor and viewed from above. Paracentesis and fluid analysis are necessary to establish a diagnosis.
EXTERNAL GENITALIA It is imperative that the mammary glands of both male and female cats be palpated on routine examination. There are normally eight glands in both sexes. Because of the high proportion of mammary gland malignancies, all masses within or between glands should be considered suspect and immediate surgical excision and biopsy is suggested. Often early pregnancy may be confirmed not only by abdominal palpation of distinct uterine enlargements but by a change in the nipples to a pink, turgid position. The vulva of both the intact and spayed female should be free of any discharge or discoloration. The spayed female's vulva is atrophied. In the intact male, the testes lie in a horizontal position within the scrotum, which is located dorsal to the penis and ventral to the anus. If
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one or both testes are absent and the cat has not been castrated, palpation of the inguinal canal may reveal their partially undescended position unless the testes are completely within the abdominal cavity. Some male cats will allow the prepuce to be withdrawn and the distal end of the penis to be examined. In the intact male, the penis is covered with minute spiny papillae that atrophy and disappear following castration. Occasionally hair rings may form at the base of the penis of a breeding tomcat, which prevents the penis from retracting back into the sheath.
CONCLUSION By themselves, an accurate medical history and thorough physical examination will often provide a diagnosis. If further diagnostic procedures are necessary, the direction and degree of these tests are dictated b y the initial examination and history. The history provides the past, the examination reveals the present, and the clinician may determine the future. Chicago Cat Clinic 5301 West Devon Avenue Chicago, Illinois 60646