Fatal intraoperative cardiac arrest after application of surgifoam into a bleeding iliac screw defect.

STUDY DESIGN: Case report. OBJECTIVE: To describe the presentation, management, and autopsy findings in a case of a fatal intraoperative cardiac arrest after application of an absorbable hemostatic agent into a bleeding iliac bone screw defect. SUMMARY OF BACKGROUND DATA: To the authors' knowledge, this represents the first reported complication of intraoperative death associated with Surgifoam (Ethicon) thromboembolization to the heart and lung microcirculation after its application into a bleeding bone defect. METHODS: A 56-year-old male was undergoing revision fusion surgery for pseudarthrosis after multilevel thoracolumbosacral fusion with pelvic fixation for degenerative scoliosis. Intraoperatively, upon removal of the right iliac screw, heavy venous bleeding was encountered, which was stopped after application of 10 mL of Surgifoam into the screw defect. Approximately 5 minutes later, the patient's end tidal CO2 dropped, and his pulse was lost. Epinephrine was administered and the patient was immediately turned to supine position and cardiopulmonary resuscitation initiated. Cardiopulmonary resuscitation was performed unsuccessfully for 30 minutes at the end of which the patient was pronounced dead. RESULTS: Autopsy findings revealed angulated particles of hemostatic agent with entrapped red blood cells partially to completely occluding small-to-medium-sized vessels of the heart and lungs. The cause of death was pulmonary and cardiac embolization of foreign material from the surgical screw defect to the vessels of the heart and lungs, significantly compromising respiration and blood flow causing sudden death. CONCLUSION: Although Surgifoam is an excellent hemostatic agent for use in spinal surgery, it must be used with extreme caution in the setting of heavily bleeding bone defects after pedicle cannulation or removal of instrumentation. In cases when brisk venous bleeding is encountered, signifying potential compromise of an emissary vein, use of other hemostatic agents such as bone wax may be a safer option. LEVEL OF EVIDENCE: N/A.

Olfactory metamorphosis in the Coastal Giant Salamander (Dicamptodon tenebrosus).

This study examined the gross morphology and ultrastructure of the olfactory organ of larvae, neotenic adults, and terrestrial adults of the Coastal Giant Salamander (Dicamptodon tenebrosus). The olfactory organ of all aquatic animals (larvae and neotenes) is similar in structure, forming a tube extending from the external naris to the choana. A nonsensory vestibule leads into the main olfactory cavity. The epithelium of the main olfactory cavity is thrown into a series of transverse valleys and ridges, with at least six dorsal and nine ventral valleys lined with olfactory epithelium, and separated by ridges of respiratory epithelium. The ridges enlarge with growth, forming large flaps extending into the lumen in neotenes. The vomeronasal organ is a diverticulum off the ventrolateral side of the main olfactory cavity. In terrestrial animals, by contrast, the vestibule has been lost. The main olfactory cavity has become much broader and dorsoventrally compressed. The prominent transverse ridges are lost, although small diagonal ridges of respiratory epithelium are found in the lateral region of the ventral olfactory epithelium. The posterior and posteromedial wall of the main olfactory cavity is composed of respiratory epithelium, in contrast to the olfactory epithelium found here in aquatic forms. The vomeronasal organ remains similar to that in large larvae, but is now connected to the mouth by a groove that extends back through the choana onto the palate. Bowman's glands are present in the main olfactory cavity at all stages, but are most abundant and best developed in terrestrial adults. They are lacking in the lateral olfactory epithelium of the main olfactory cavity. At the ultrastructural level, in aquatic animals receptor cells of the main olfactory cavity can have cilia, short microvilli, a mix of the two, or long microvilli. Supporting cells are of two types: secretory supporting cells with small, electron-dense secretory granules, and ciliated supporting cells. Receptor cells of the vomeronasal organ are exclusively microvillar, but supporting cells are secretory or ciliated, as in the main olfactory cavity. After metamorphosis two distinct types of sensory epithelium occur in the main olfactory cavity. The predominant epithelium, covering most of the roof and the medial part of the floor, is characterized by supporting cells with large, electron-lucent vesicles. The epithelium on the lateral floor of the main olfactory cavity, by contrast, resembles that of aquatic animals. Both types have both microvillar and ciliated receptor cells. No important changes are noted in cell types of the vomeronasal organ after metamorphosis. A literature survey suggests that some features of the metamorphic changes described here are characteristic of all salamanders, while others appear unique to D. tenebrosus.