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Bone Aspiration and Biopsy 1067

a small-gauge needle attached to a pressure
transducer or catheter placement in a distal
VetBooks.ir to pressure tubing and a pressure transducer. A
artery (typically dorsal pedal) and attachment
BP tracing is printed, and systolic and diastolic
pressure can be determined from the pressure
tracing.
• Highly accurate information because direct
measurement is used
• Local anesthesia is used to minimize
discomfort.
• Arterial puncture or arterial catheter place-
ment requires more technical skill than
noninvasive methods (p. 1058).
• Bleeding may occur at site of arterial punc-
ture; apply pressure to puncture site for at Procedures and Techniques
least 5 minutes after the needle is withdrawn.
• Invasive methods are rarely used in conscious
clinical patients, but indwelling arterial
BLOOD PRESSURE MEASUREMENT Automated oscillometric method used with a forelimb cuff to obtain
systolic, diastolic, and mean blood pressure in a dog. Dog is restrained in a comfortable position, with intended catheters are frequently used for continuous
cuff-site limb gently extended. Cuff is positioned at mid-radius level, and limb is positioned such that cuff is BP assessment in anesthetized or critically
at level of right atrium during readings. ill patients.
Pearls
Cuff location, cuff size, and animal position
representative number for systolic, diastolic, Postprocedure can affect measured BP values. Each of these
and mean pressures, respectively. • Record the average values in animal’s record, should be noted for each patient and remain
• If heart rate associated with a reading is clearly with notation of method, cuff size, and cuff the same for future BP assessments.
incorrect, BP values may be spurious. High site used.
heart rate during recording may indicate high • Evaluate BP values in light of clinical findings SUGGESTED READING
animal stress levels and possible elevated BP and level of anxiety or excitement during BP Brown S, et al: Guidelines for the identification, evalu-
due to stress of procedure. If heart rate is measurement. ation, and management of systemic hypertension in
decreasing during serial measurements, take dogs and cats. J Vet Intern Med 21:542-558, 2007.
several more readings and average the final 5 Alternatives and Their AUTHOR: Rebecca L. Stepien, DVM, MS, DACVIM
values. If an arrhythmia is present, the heart Relative Merits EDITORS: Leah A. Cohn, DVM, PhD, DACVIM; Mark S.
rate may not be recorded and the results of Invasive BP measurement involves acute arte- Thompson, DVM, DABVP
that iteration should be discarded. rial puncture (typically femoral artery) with

Bone Aspiration and Biopsy Bonus Material
Online

Equipment, Anesthesia
Difficulty level: ♦ • For biopsy: sterile gloves, #11 scalpel blade,
• Heavy sedation, neuroleptanalgesia, or Jamshidi needle or bone trocar, tissue jar,
Synonym general anesthesia with local analgesic for and 10% formalin
Bone fine-needle aspiration (FNA) biopsy
○ Typical sedation protocol: dexmedetomi- Anticipated Time
Overview and Goal dine 5 mcg/kg IM or IV with morphine 15-20 minutes
Minimally invasive sampling of bony mass or 0.5 mg/kg IM or IV
lesion identified radiographically ○ Typical general anesthesia protocol: Preparation: Important
premedicate with above sedation drugs, Checkpoints
Indications induce with propofol 6 mg/kg IV to effect, • Radiographs: confirm lesion and best
Used to obtain diagnosis of bony mass or maintenance with propofol as needed or sampling location
radiographic aggressive bone lesion (pp. 165, isoflurane gas • Thoracic radiographs: to check for metastatic
725, and 726). Simple aspiration often used ○ Local analgesia: 9 : 1 mixture of 2% lido- disease from primary bone tumors
first, moving on to a biopsy if diagnosis is not caine HCl to sodium bicarbonate 1-2 mL • Discussion with owner of potential complica-
forthcoming. infiltrated subcutaneous to periosteum tions, including iatrogenic pathologic fracture
• Clippers
Contraindications • Antiseptic scrub solution, isopropyl alcohol, Possible Complications and
• Contraindication to sedation or anesthesia gauze squares for skin preparation Common Errors to Avoid
(biopsy) • For aspiration: sterile or nonsterile gloves, • Iatrogenic pathologic fracture: altering angle
• Severe bleeding disorder hypodermic needles (18 or 20 gauge), 10-mL or location of multiple samples may reduce
• Skin infection over bone sampling site syringe, cytology slides (#10-#20) risk.

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