An axial pattern flap that was based on the sternocleidomastoideus branches of the caudal auricular artery and vein was developed. Control flaps, which included ligation and division of the caudal auricular artery and vein, were similarly developed on the contralateral aspect of the neck. Mean survival of caudal auricular artery axial pattern flaps (85.2%), compared with control flaps (63.9%), was significantly different (P < 0.05). On the basis of results of this study, an axial pattern flap based on the sternocleidomastoideus branches of the caudal auricular artery and vein may be a source of skin for reconstructive procedures of the head and neck.

A rapid, simple chemosensitivity assay, assessing tumor cell nuclear uptake of doxorubicin hydrochloride, was evaluated in 16 dogs with appendicular osteosarcoma. Doxorubicin was administered to dogs in 5 biweekly treatments, and surgical resection was performed after the second or third treatment, The chemosensitivity assay was performed on biopsy specimens from all dogs before chemotherapy. It was repeated on tissue from resected tumors, and tumors were evaluated histologically to determine the degree of necrosis resulting from chemotherapy. Disease-free and total survival time correlated significantly (P < 0.05 in both cases) with the degree of postchemotherapy necrosis of the primary tumors. Significant correlation was not apparent between the percentage of tumor cells with nuclear uptake of doxorubicin (in either biopsy or resection samples) and disease-free or total survival time. The percentage of cells with nuclear uptake of doxorubicin in surgically resected tumors correlated significantly (P < 0.05) with percentage of necrosis,

The effect of humidity on the histologic lesions induced by high-frequency jet ventilation was investigated in 12 healthy cats. After 16 hours of ventilation, the appearance of the tracheal epithelium ranged from normal to necrotic. The damage was considerably more severe in the trachea of cats of the group ventilated without added humidity. Increasing the relative humidity to 63% at 24 C had a protective effect, but further increasing the relative humidity to 92% at 35 degrees C did not appear to provide significantly more protection. The bronchi and distal airways had minimal, if any, damage in all groups.