27 de jan. de 2012

Intracranial variables in propofol or sevoflurane-anesthestized dogs subjected to subarachnoid administration of iohexol

Variáveis intracranianas em cães anestesiados com propofol ou sevofluorano e submetidos à administração subaracnóidea de iohexol

N. Nunes; A.V. Leite; D.P. Paula; C.T.D. Nishimori; A.P. Souza; P.S.P. Santos; P.N. Henao Guerrero; P.C.F. Lopes

Arq. Bras. Med. Vet. Zootec. vol.63 no.6 Belo Horizonte dez. 2011

ABSTRACT

The effects of subarachnoid administration of iohexol on intracranial hemodynamic in dogs anesthetized with propofol or sevoflurane were evaluated. Thirty adult animals (10.9±2.9kg) were distributed into two groups: PG, where propofol was used for induction (10±0.5mg/kg), followed by a continuous rate infusion at 0.55±0.15mg/kg/hour, and SG, where sevoflurane was administered for induction (2.5 MAC) and for anesthetic maintenance (1.5 MAC). A fiberoptic catheter was implanted on the right superficial cerebral cortex to monitor intracranial pressure (ICP). After 30 minutes, cerebrospinal fluid (CSF) was collected at the cisterna magna and iohexol was injected. The measurements were performed before CSF collection (TA), after the iohexol injection (T0), and at 10-minute intervals (T10 to T60). Intracranial pressure decreased at T0 in SG. Cerebral perfusion pressure at T0 was higher than at TA, T50 and T60 in PG, but in SG, the mean value at T0 was higher than the ones from T20 to T60. Mean arterial pressure at T0 was higher than at TA in PG, while in SG, the values from T20 to T60 were lower than at T0. The heart rate at T60 was lower than at T0 in PG. Cardiac output at TA was lower than at T60 in SG. The cerebrospinal fluid collection and administration of iohexol promoted decrease in intracranial pressure in sevolflurane-anesthetized dogs and increase in cerebral perfusion pressure in propofol-anesthetized dogs.

25 de jan. de 2012

Hemangiossarcoma cutâneo com metástase no sistema nervoso central de um canino

Cutaneous hemangiosarcoma with metastasis in the central nervous system of a canine

Kilder Dantas Filgueira, Paulo Fernando Cisneiros da Costa Reis, Jael Soares Batista & Valéria Veras de Paula

Acta Scientiae Veterinariae, 2012. Pub 40(1): 1024

ABSTRACT

Canine hemangiosarcoma is a malignant neoplasm of endothelial cells. Such tumor has most commonly its primary location in the spleen, right atrium, subcutaneous tissue and liver. In general, metastases occur in the liver, omentum, mesentery and lung. The nervous system may be a metastasis site, but with rare spinal cord involvement. This paper aims at the description of canine cutaneous hemangiosarcoma with metastasis to the central nervous system.Case: A dog presented history of skin neoplasia. The patient underwent physical examination, which detected an exophytic tumor in the foreskin. Needle aspiration of the lesion was carried out, suggesting the presence of malignant neoplasm of mesenchymal origin. So, the lesion surgical excision was the option. Before the procedure, complementary preoperative examinations of the patient were required. Those corresponded to chest radiographs, abdominal ultrasound, complete blood count, serum urea, creatinine, alanine aminotransferase, aspartate aminotransferase and total protein. The image diagnostic of the thoracic and abdominal cavities showed no noteworthy changes. The hematology and serum biochemistry were normal. The tumor obtained during surgery was sent for histopathological analysis, whose diagnosis corresponded to hemangiosarcoma. Chemotherapy treatment was not possible in the animal. Nine months after the surgery, alterations in the canine movement were detected as well as postural reactions of the right forelimb, with paresis and reduced proprioception of the same. Hyperesthesia was also found in the spine, in the cervical and thoracic segments. Due to the patient’s clinical condition, euthanasia was recommended. The animal was sent for autopsy, where the main macroscopic lesions were dark red areas in the left brain and spinal cord compression by a tumor between the bodies of the seventh cervical vertebra and the fi rst chest one. All material was sent for histopathological examination, which revealed the presence of hemangiosarcoma in the structures examined, suggesting metastasis to the central nervous system from the primary cutaneous site.Discussion: The majority of dogs with cutaneous hemangiosarcoma, during the initial clinical presentation, have already presented a primary tumor in another organ. However, in the present report, there was an inversion of this quotation, since the initial site of the tumor probably corresponded to the skin as, during the fi rst approach, the patient’s chest radiographs and abdominal ultrasound did not reveal metastastic injuries. Also, at that time, the dog did not exhibit clinical signs related to tumor spread, unlike the symptoms observed after nine months. To hemangiosarcomas with location in the frontal lobe of the brain, contralateral postural reaction defi cits can be observed. Such statement may justify, for the case under discussion, the association of the lesions in the left cerebral hemisphere with disabilities in the proprioception in the rightforelimb. Hemangiosarcomas of the spine with extradural location cause gradual compression of the spinal cord and thus favor the development of progressive myelopathy symptoms. This quote could explain the spine hyperesthesia and the monoparesis reported in the animal. The histopathology of skin tumors is essential to establish the defi nitive diagnosis and for better understanding of future pathologies.