Page 313 - Clinical Small Animal Internal Medicine

28 Pericardial Disease 281

(a) (b)
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Figure 28.4 Echocardiographic images obtained from a right parasternal long‐axis view in a dog with pericardial effusion and
collapse of the right atrium (arrow) caused by elevated intrapericardial pressure. Ao, aorta; LA, left atrium; LV, left ventricle;
PE, pericardial effusion.

Scalpel blade. 1) For the procedure, the patient is positioned in sternal
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Collection bowl and graduated cylinder or other or lateral recumbency with continuous ECG attached.
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volume measuring tool. 2) Identify the ideal position for introducing the cathe-
Red‐top tube containing no anticoagulants or ter into the thorax, which is often around the fifth or
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preservatives. sixth intercostal space, mid‐thorax at the costochon-
Purple‐ or lavender‐top tube containing EDTA as an dral junction. It can be found by flexing the right front
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anticoagulant. limb and swinging the leg across the thorax and using
Sterile gloves. the intercostal space where the point of the elbow
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Local anesthetic block. crosses the costochondral junction (Figure 28.6a) or
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Continuous ECG – recommended for detecting with ultrasound guidance (Figure 28.6b). A perma-
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arrhythmias generated by contacting the heart when nent marker can be used to identify the spot for cath-
advancing the catheter into the pericardial space. eter entry or to mark multiple spots on the perimeter
Echocardiogram/ultrasound machine – useful for of the shaved area to triangulate the position.
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identifying a location on the right side of the thorax for 3) Following sterile preparation of the pericardiocente-
obtaining the most direct access to pericardial fluid. sis site, inject a local anesthetic block to the skin,
Sedation – may be required to facilitate the procedure intercostal muscles, and pleura (Figure 28.6c). The
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in some cases. discomfort associated with the local block can limit
its value in some dogs that would otherwise benefit
Preparation from sedation. After approximately five minutes, use
Prior to performing the procedure, gather the supplies a scalpel blade to make a small stab incision in the
appropriate for the patient’s size, demeanor, and clinical skin to facilitate catheter insertion and advancement.
status. Putting together a prestocked kit that contains 4) Attach the catheter to the extension set tubing with a
the necessary supplies for pericardiocentesis is very use- three‐way stopcock placed between the extension set
ful, especially for immediate access in an emergency sit- tubing and a syringe. At the predetermined ideal peri-
uation. Light sedation may be required to facilitate the cardiocentesis site, advance the catheter through the
procedure in some cases. The local anesthetic block can skin, followed by the intercostal muscles, avoiding the
be drawn into a syringe, and the right side of the thorax caudal aspect of the rib where the intercostal vessels
can be shaved in preparation for the procedure. are located, and into the pleural space (Figure 28.6d).
An assistant applying gentle negative pressure on the
Procedure (Figure 28.6) syringe may encounter pleural effusion that is typi-
Pericardiocentesis is routinely performed on the right cally straw colored in patients with right heart failure.
side of the thorax to utilize an approach through the car- Continue advancing the catheter until a scratching
diac notch between lung lobes and to avoid damage to sensation is detected when the needle comes into
the lung and coronary arteries. contact with the pericardium. Continue to advance