Anaphylactoid Response to Optison and Its Effects on Pulmonary Function in Two Dogs

Abstract

ABSTRACT. Two of 26 anesthetized dogs given the cardiac echo-enhancing agent Optison ® showed anaphylactoid responses (AR) related to the human albumin component of this agent. The episodes of AR were self-limited, and could be reproduced by human albumin injection alone. Gas exchange was maintained by mechanical ventilation and 5 cm H 2 O PEEP, and dispersion of ventilation remained normal during AR despite severe hypotension. We suggest that: (1) pre-screening by measuring blood pressure response to intravenous injection of small doses of Optison ® , and (2) availability of access to the airway in addition to emergency agents may be prudent preventive measures when Optison ® is used in animals to enhance echocardiographic imaging.KEY WORDS: gas exchange, human albumin, hypotension.

Safety of contrast-enhanced ultrasonography in dogs and cats: 488 cases (2002–2011)

“…In human patients with a high cardiologic mechanical index and systolic triggering, CEUS can elicit premature ventricular contractions. Although none of the case animals that were administered the perflutren protein type A microsphere contrast agent in the present study developed adverse events, the proportion of study animals that received that contrast agent was small, and on the basis of results of the other study, 23 administration of the perflutren protein type A microsphere contrast agent is not recommended in animals. At the cellular level, microbubble contrast agents cause microvascular rupture, which can be useful for delivery of the agent to particular parts of the body that are otherwise difficult to access (ie, across the blood-brain barrier); however, damage to endothelial cells caused by the contrast agents was not permanent.…”

“…19 Hypersensitivity reactions following administration of a microbubble contrast agent are rare. In that study, 23 2 dogs that were administered a perflutren protein type A microsphere contrast agent developed anaphylactoid reactions with severe self-limiting hypotension, which was believed to be the result of the dogs reacting to the human albumin component of that contrast agent. 20 In the present study, only 1 animal (dog) had CEUS of the heart performed, and no adverse reactions were reported for that animal.…”

Echocardiography

“…130 The risk of anaphylactoid reactions with commercial contrast agents should be noted, 131 and that human patients have died suddenly following injection of these products. At times negative contrast effects are visualized when blood derived from the left heart crosses a shunt and dilutes the positive saline contrast in the right heart.…”

Advanced Ultrasound Techniques

“…Structures adjacent to the digestive lumen, such as the hilum of the liver, shift from the vasculature is below 1 cm/sec, which prevents detection of slow flowing capillary blood. 68,69 First and second generation agents are small enough to pass through the pulmonary circulation (typically 3 to 10 µm in diameter) and consequently have a longer circulatory half-life than agitated saline. Combining power Doppler with ultrasound contrast agents results in improved detection of small vessels, although imaging of capillary sized vessels remains impossible because of limited contrast resolution (Figure 3-10).…”