COMMON FEMORAL ARTERY FENESTRATION IN THE TREATMENT OF THORACIC AORTIC DISSECTION

SUMMARY Although dissection of the thoracic aorta is a common aortic emergency, little has been written about fenestration procedures to revascularise femoral arteries that have been occluded by dissecting aneurysms arising from as high as the thoracic aorta.     

Postoperative cardiac surgical care: an alternative approach

Combined appropriate anaesthetic and surgical techniques have allowed increasing numbers of patients to be successfully managed in a general surgical recovery ward after cardiac surgery rather than in an intensive care unit. From 1983 to 1989, 933 of 1542 patients undergoing open heart surgery were transferred to the general surgical recovery ward in the immediate postoperative period. Of these, 718 (77%) had undergone coronary artery bypass grafts, sometimes combined with other procedures and 168 (18%) had had cardiac valve replacements with or without other procedures. The remaining 47 (5%) had had miscellaneous cardiac operations. Significant cardiac complications occurred in 29 (3%) patients. The 24 hour chest radiograph was reported as abnormal (mainly atelectasis and effusion) in 63% of patients. Most resolved spontaneously or with physiotherapy. Twenty nine (3%) patients were re-explored to achieve haemostasis. There were no deaths in the general surgical recovery ward. Thirty seven (4%) patients had to be transferred to the intensive care unit for various reasons. The remaining 896 patients were transferred to the general ward after one night (871 patients) or two nights (25 patients) in the general surgical recovery ward. The average duration of stay in hospital for these patients was 9·3 days. Because of the overall success of such management and the low rate of complications over 80% of patients are now managed in the general surgical recovery ward after open heart surgery. The resulting savings in capital expenditure of equipment, medical, nursing, and technical personnel are substantial, and there are major implications for the planning of new cardiothoracic units.     

Blue toe syndrome: treatment with percutaneous atherectomy

"Blue toe syndrome" refers to digital ischemia of the foot in the presence of palpable or Doppler audible pedal pulses. This clinical syndrome is caused by microembolization to small vessels from a proximal source. The use of percutaneous transluminal atherectomy is described in the treatment of embologenic superficial femoral artery lesions in seven patients. All seven had prompt healing of the ischemic toes, and none required surgical revascularization or amputation. One patient developed a recurrent stenosis at the atherectomy site and had a second episode of digital ischemia, which was treated by means of atherectomy with a larger device. Histologic study of atherectomy specimens suggests that emboli arise from adherent fibrinoplatelet aggregates or thrombus and less often from cholesterol-rich atheromatous plaque. Although either percutaneous transluminal angioplasty or atherectomy can be used to treat the underlying stenosis, percutaneous atherectomy offers the advantage of nonsurgical removal of embologenic material and provides material for histologic study. Percutaneous atherectomy is an effective method of treating embologenic superficial femoral stenoses in patients with ipsilateral blue toe syndrome.     

The in vitro production and characterization of neutrophils from embryonic stem cells

An embryonic stem (ES) cell/OP9 coculture system for the effective production of functional neutrophils is described. A 3-step differentiation strategy was developed that uses liquid culture, enabling reliable and abundant production of neutrophils at high purity without the need of sorting for isolation of mature neutrophils. Use of the OP9 stromal cell line significantly enhances the number, percentage, and duration of differentiated neutrophils produced from embryonic stem cells. Effective and sustained differentiation of ES cells into neutrophils provides a useful model system for studying neutrophil differentiation and function and the factors that regulate them. Morphologic and functional evaluation of these ES-derived neutrophils indicates that large numbers of mature neutrophils can be produced from pluripotent ES cells in vitro. Specifically, their morphology, ability to produce superoxides, flux calcium, undergo chemotaxis in response to macrophage inflammatory protein 2 (MIP-2), stain for the granulocyte-specific marker-specific chloroacetate esterase, and contain the neutrophil-specific markers Gr-1 and the mouse neutrophil-specific antigen indicates that they are comparable with purified mouse bone marrow neutrophils. They also express gelatinase and lactoferrin granule proteins. During the differentiation of these ES-derived neutrophils, regional areas of neutrophil production can be identified that have been designated as neutrophil generating regions (NGRs).     

Massive proteinuria and acute renal failure in a patient with acute silicoproteinosis.

Acute pulmonary silicoproteinosis, massive proteinuria and fatal renal failure developed in a 23 year old male sandblaster. Examination of the kidney by immunofluorescence revealed granular deposits of immunoglobulin M (IgM) and the third component of complement (C3) along the glomerular basement membrane. Light microscopy disclosed mild proliferative glomerulonephritis with loss of colloidal iron staining for sialoprotein, and electron microscopy disclosed an increased density of epithelial cytoplasm, altered lysosomes and endothelial cell microtubular structures. The silicon content of the kidney was 264 parts per million (ppm), but particles of silicon were not demonstrated by electron microscopy. No primary or systemic causes of renal diseases were elucidated. The renal dysfunction apparently resulted from acute renal silicon toxicity, a new complication of acute pulmonary silicoproteinosis.