Case Studies In Small Animal

Cardiovascular Medicine

Home Up 1    Pleural Fluid 2              Cough 3   Heart Murmur 4           Syncope 5       Tachypnea 6           Cyanosis 7   Heart Murmur 8   Heart Murmur 9              Cough 10    Heart Failure 11              Ascites 12    Pleural Fluid 13           Syncope 14     Bradycardia 15     Tachycardia 16                Blind 17   Heart Murmur 18   Resp. Distress 19        Collapsing 20    Heart Failure 21          Paralysis 22    New Murmur 23              Cough 24          Vomiting 25       Tachypnea 26   Heart Murmur 27      Hemoptysis 28  Limb Swelling 29  Heart Murmur 30 Acute Collapse 31 Enlarged Heart 32               Blind 33             Cough 34         Collapse 35         Collapse 36 Thromboembolus 37  Heart Murmur 38  Heart Murmur

.    Radiographs 2D Echo Color Flow Diagnosis

Case 22

Primary Clinicians: Janet Aldrich, DVM & Aaron Wey, DVM

Supervising Clinician: Mark D. Kittleson, DVM, PhD, DipACVIM (Cardiology)

Signalment

13-year-old FS Australian Shepherd Cross weighing 20 kg ("Chimere")

First Visit

Presenting Complaints

Non-weight bearing lameness & vomiting

Pertinent History

bullet Non-weight bearing lame on right front leg began Saturday 10/30/99.
bullet Chimere began to vomit Sunday evening and was febrile (temp=104.0). The initial vomitus contained chicken, later becoming only bile stained fluid. Owner administered famotidine and 75 mg Baytril. Vomiting has since stopped. 
bullet Remaining medical history includes: Shifting leg lameness of long standing duration. Owner reports that Chimere has slowed down over the last year and appears weak in the hind quarters. She stumbles when running and does not seem to be able carry toys in her mouth. Within the last two weeks owner has noticed seizure like activity as evidenced by facial twitching and tooth chattering.
bullet A neurology consult was completed this morning revealing underlying neuropathy which may explain recent changes in Chimere's activity and coordination, however, Chimere's poorly defined neurologic condition is thought to have little to do with her presentation today.
bullet Other treatment history includes Rimadyl and glucosamine/ chondroitin over the last year for chronic arthritis. 

Physical Examination

bullet Obtunded and lethargic. No change in skin turgor noted. T=104.2; P=120; R=30. 
bullet Coat is clean and dry. Skin is clean, no lacerations, erythema noted. Abdomen shaven for ultrasound. 
bullet CRT=1.5 sec. Facial expression symmetrical. Marked nuclear sclerosis OU, normal PLR, otherwise clean and clear. Ears with mild discharge bilaterally. Tonsils in crypts. Canines
bullet fractured, incisors worn, severe calculus with moderate gingivitis. Serous discharge noted from both nares. 
bullet Non-weight bearing lame on right front. Unwilling to stand without support. Right Lateral metacarpus swollen and painful on palpation. Right elbow also painful on manipulation, no
bullet swelling or effusion is noted. Musculature over R & L hip atrophied, with no apparent lameness. 
bullet Adequate pulses with occasional dysrhythmia noted. No murmurs ausculted. 
bullet Exaggerated respiratory pattern. Breaths sounds on inspiration dorsally and ventral on the LEFT, markedly diminished breath sounds on the right dorsally. 
bullet Liver not palpable, caudal pole of left kidney not palpable. Gut loops are smooth. 
bullet Bladder palpates small. Vulva clean, no discharge noted. Rectal revealed symmetrical ventral coccygeal muscles, small urethra, moderately full anal sacs R & L, and soft formed brown stool. 
bullet Neurologic consult revealed ill-defined neuropathy. Cranial nerves intact. 
bullet Submandibular 1/4 cm, prescapular = 1 cm, popliteal = 1 cm. 

Problems

bulletFever (rename = sepsis) 
bulletVomiting (rename = sepsis) 
bulletLiver disease (rename = sepsis) 
bulletRight front limb lameness 

Visit Summary

bullet Problem 1 (Fever)

O: T= 104.4 (spiked at 105.2), WBC=21,100 (neutrophils = 20,256; lymphocytes=211), platelets=148,000, plasma fibrinogen=600, protein : fibrinogen=13, anion gap=31, potassium=3.7, creatine kinase=499. Urinalysis revealed 4+ protein, 5-10 WBC per hpf, 2-5 RBC per hpf, rare transitional epithelial cells, gram positive cocci. Arterial blood gas revealed PCO2 of 20.8, PO2 of 90.5, HCO3=13 and base deficit of -10. Thoracic radiographs were within normal limits; abdominal ultrasound revealed a course textured liver but was otherwise unremarkable. Initial antibiotic therapy with oxacillin resulted in vomiting (treatment discontinued).

A:  Presence of gram-positive cocci in urine sediment highlights infection as a likely source of fever. Given the degree of lethargy and fever, if infection is indeed the underlying etiology, sepsis is suspected. Leukocytosis with neutrophilia (w/slight toxicity) and a left shift as well as an elevated fibrinogen also highlight the likelihood of infection. Blood cultures are pending to rule in/out a septic process. Inflammatory causes of fever including liver disease and joint disease have not been ruled out at this time. Further diagnostics including liver biopsy and joint taps would be required to identify underlying liver and joint pathology and are not being pursued at this time. 

P: Diagnostic- Blood culture results pending to rule-out sepsis. Therapeutic: Timentin (ticarcillin) 50 mg/kg IV q 6 hours (given slowly over ten minutes). Monitor temperature q 1 hour. Offer 100 ml water q 2 hours. LRS qs to 20 mEq KCl at 100 ml/hr (2 times maintenance). As the owner is a veterinary technician she has opted to care for Chimere at home during the evening. Owner has been instructed to continue antibiotic and fluid therapy throughout the evening. Chimere need to be turned every few hours to alleviate any chronic pressure from being recumbent.

 

bullet Problem 2 (Vomiting): Vomiting had ceased since approximately 3 AM this morning following the administration of famotidine. Chimere vomited only once today after the administration of Oxacillin IV. Treatment was discontinued and replaced with Timentin without further incidence.

 

bullet Problem 3(Liver disease):

S/O: U/S revealed course textured liver. ALT=537, Alk Phos=621, Bilirubin total=.5, cholesterol=597, GGT=18.

A: The increased ALT and GGT is possibly due to long-standing Carprofen treatment for noted arthritis. Causes for an increased Alk Phos include intrahepatic (swelling of hepatocytes) and extrahepatic (obstruction). Hyperbilirubinemia may be indicative of intrahepatic disease as well, but may also increase with cholestasis or hemoglobin catabolism as seen with hemolysis.

P: Defining the exact nature of Chimere's hepatic disease would require biopsies and will not be pursued at this time.

 

bullet Problem 4 (Lameness)-

S/O: Non-weight bearing lame on right front leg. Orthopedic consult agreed that the right elbow was painful on palpation, although no swelling or effusion was appreciated. The right carpus is painful and warm to the touch. Radiographs of right carpus revealed a soft tissue swelling of the lateral metacarpus, with irregular bony changes at the 4th metacarpal bone. Radiographs of the right elbow were remarkably normal. 

A: There appears to be no radiographic evidence to explain the degree of lameness exhibited by Chimere. There are no obvious outward signs of trauma or penetrating wounds. Rule-outs for lameness include infection, inflammation, trauma and neoplasia. Although infection may be a likely source when considering an underlying septic process, joint taps would again be required to define the underlying etiology and will not be done at this time.

P: Antibiotic therapy as described earlier. Note any swelling, erythema in the area. 

Clinical Diagnoses

bulletSepsis 
bulletRight forelimb lameness (metacarpus and elbow) 

Second Visit (Next Day)

Visit Summary

bulletProblem 1 (Septicemia)

S/O: Chimere appears to be feeling better today. She is in sternal recumbency some of the time, drinking on her own, no longer obtunded but remains very lethargic. Rectal temperature at days end was 103.2. CBC revealed a leukocytosis with neutrophilia and a left shift, plasma fibrinogen of 600 and a protein : fibrinogen of 13. Urinalysis revealed 4+ proteinuria, moderate numbers of WBC and RBC. Culture of urine sediment as well as blood grew pure Staph. intermedius. Blood gas analysis was indicative of metabolic acidosis and attempted compensatory respiratory alkalosis (base deficit -10, pCO2 =20.8, PO2 = 90). Chimere was placed on IV fluids (LRS qs to 20 mEq KCl), administered 20 mEq sodium bicarbonate and started on IV antibiotics. Current antibiotic therapy includes Timentin @ 50mg/kg IV QID (initial therapy with oxacillin was discontinued given that first administration resulted in vomiting). Urine and Blood culture sensitivities are pending. Recheck blood gases....pH=7.34, pCO2 25.5, pO2 51.9, HCO3=12.9, base deficit=-10, K=3.4, Na=146, Ca=1.02, O2 sat=79%. 

A: Antibiotic therapy appears to be addressing Chimere's septic process. Her degree of pyrexia has steadily decreased throughout the day and continues to improve as does her general attitude. Hypokalemia may be associated with obvious decrease in intake/anorexia, or an increased output via fluid diuresis. 

P: therapeutic - Continue antibiotic therapy (Timentin 50 mg/kg QID IV), 20 MEq NaHC03 IV over 1 hour, recheck blood gases and electrolytes in the morning. owner education - owner has again elected to care for Chimere at home this evening. Owner had been instructed to continue therapy and turn Chimere every four hours to alleviate any chronic pressure on her down side.

bullet Problem 2 (Right forelimb lameness)

S/O: Although still not bearing any weight on her right front leg, the metacarpal area is not as painful on palpation, but is still mildly swollen and warm to the touch. 

A: As there was no definitive explanation from previous radiographs and the problem does not appear to worsening, no further diagnostics will be pursued at this time. 

P: Recheck BID for increased swelling or pain.

Discharge Instructions

bullet Please continue fluid therapy for Chimere at home this evening at 100 ml/hr.
bullet Timentin IV every 6 hours IV slowly over 10 minutes. 
bullet Monitor temperature every 4 hours. 
bullet Rotate every four hours to prevent pressure sores. 

Third Visit (Third Day)

Pertinent History

bulletChimere presents today for continued therapy and monitoring.
bulletOwner reports that Chimere seems to be improving.
bulletShe was force fed 2 tbsp of cat food last evening and did not vomit.
bulletHer fever has decreased throughout the evening and by early this morning was down to 102.6. 

Physical Examination

bullet General: Sitting sternal, very quiet. Is looking brighter than yesterday. Chimere now makes an effort to stand when you pick her up, but she can not remain standing for even a short length of time. Appears painful when attempting to stand although focal pain response is limited to metacarpus. 
bullet Integ: Coat clean and dry. Skin over right metatarsus is red and bruised (site used for venipuncture) as is the medial right metatarsus. 
bullet E/E/N/T: Eyes clean, no conjunctival hyperemia noted, marked nuclear sclerosis OU. Ears with mild exudate, no odor or erythema noted. Nose is dry, no discharge present, planum nasale is hyperkeratotic, dry and crusty. Tonsils in crypts. 
bullet M/S: Will bear some weight on R forelimb. BCS 4/9. Unable to stand for any length of time unassisted. 
bullet C/V: Heart murmur ausculted over mitral (3/6). Increased breath sounds on inspiration. 
bullet GI/U: Liver, left kidney not palpable. Gut loops smooth, bladder empty. 
bullet LN: submandibular, 1/4 cm, prescapular 1/2 cm , popliteal = 1 cm.

Problems

bullet Staph septicemia 
bullet Right forelimb lameness ( lateral metacarpus, and elbow)
bullet2-3/6 systolic heart murmur 

Discharge Summary

bullet Problem 1 (Septicemia)

S/O: Chimere appears to be feeling better today. She is sitting upright, drinking water on her own and ate 2 tbsp of A/D twice today without vomiting. Bacteriological isolate report is sensitive to Timentin. 3/6 Heart murmur recognized on PE this AM.

A: Antibiotic therapy appears to be addressing Chimere's septic process. The appearance of a heart murmur at this time is likely due to vegetative endocarditis as a sequel to sepsis. Other rule outs for a sudden murmur include anemia, and ruptured chordae tendineae. Cardiac ultrasound necessary to define the underlying etiology of the heart murmur will not be pursued at this time given owner's desire to keep costs down and that answers to this question will not change our given course of therapy. 

P: Continue antibiotic therapy (Timentin 50 mg/kg QID). IV Fluids at 10 ml/ht qs to 10
mEq KCl. Owner has again elected to care for Chimere at home this evening. 

bulletProblem 2 (R forelimb lameness)

S/O: Although still swollen and red over the metacarpus, Chimere is placing some weight on this limb when standing. Elbow is not painful to palpation. Toes are warm, no edema except at the focal area described above.

A: At this time the problem appears to be static as no further diagnostics will be pursued at this time the underlying etiology (trauma, infection, inflammation, neoplasia) remain unclear.

P: Continue checking foot for increased swelling, pain and redness.

Author's Note

Because of the owner's reluctance to pursue further diagnostics, a cardiac consultation was not performed until 5 days later. The diagnostic test results are on the following pages.

Mark D. Kittleson, D.V.M., Ph.D. All rights reserved.