Aneurysms of the aorta a consideration of pre- and postoperative medical management

The mortality following excision of aneurysms of the thoracic and abdominal aorta has been acceptably low and forms a sharp contrast with the mortality figures of unoperated series. Over 2,500 aneurysms of various types have been resected by the surgical group at the Baylor University College of Medicine. The mortality rate for resection of abdominal aneurysms is about 9 per cent over-all, a figure which includes those with and without associated heart disease and also includes those which had ruptured at the time of admission. The mortality rate for descending thoracic aneurysms is 20 per cent and that for all thoracic aneurysms about 26 per cent. A 5 year survival figure of patients after abdominal aneurysmectomy was 58 per cent contrasted with 9 per cent in the nonoperated series of Estes and Wright. An analysis of 179 patients with dissecting aneurysms disclosed an operative mortality of 21 per cent. When the dissection began beyond the origin of the left subclavian, the operative mortality among the 94 patients operated upon in the past 5 years was only 12 per cent.

Despite the high incidence of hypertensive disease, ischemic heart disease and associated cardiorenal abnormalities, most patients can be carried safely through surgery. There are virtually no late complications which are unique to this group of patients. In order that the operative and postoperative course may be smooth as possible, careful attention must be given to the possible presence of any abnormality of cerebrovascular, cardiopulmonary, renal and hepatic function. Associated disease such as occlusive disease of arteries supplying the lower extremities, hiatal hernia, cholelithiasis should be searched for in order that they may be corrected at the time of the aneurysmectomy if the operative approach permits. The cardiologist or internist plays a vital role in preoperative work-up as well as the operative and postoperative periods and it is of fundamental importance that he understand the problems related to each of these phases.     

Is end-stage deceleration of the fetal heart ominous?

Summary. End-stage deceleration (ESD) defined as deep and sustained fetal bradycardia during the second stage of labour was observed in 55 patients. Fetal well-being and neonatal outcome were assessed with fetal-scalp pH, umbilical-vein pH and l-min Apgar score values. Only six infants with pathological fetal heart-rate patterns before ESD had a l-min Apgar score of <7 and an acidotic umbilical-vein pH. The remaining 49 babies were born in excellent condition, although when ESD persisted for more than 15 min umbilical-vein pH decreased.     

Circulating levels of pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotrophin (hCG) in intrauterine and extrauterine pregnancies

Summary. Pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotrophin (hCG) have been measured in the plasma of pregnant and non-pregnant women attending the outpatient clinic for suspicion of pregnancy. The plasma concentrations obtained were grouped into intrauterine or extrauterine pregnancies and compared with values obtained in non-pregnant patients with similar periods of amenorrhoea. Patients with ectopic pregnancies had slightly lower PAPP-A levels and significantly lower hCG concentrations than those in women with normal intrauterine pregnancies. Non-pregnant women had very low hCG and PAPP-A levels compared with those in pregnant patients. These data suggest that in patients with extrauterine pregnancies the poorly sustained ectopic trophoblast is unable to produce normal concentrations of hCG and probably PAPP-A and that the slightly diminished levels of PAPP-A in ectopic pregnancies might be derived from a decidual production.     

Factors related to degradation of articular cartilagein osteoarthritis: a review

Objectives:

Osteoarthritis (OA) is a common joint deterioration initiated by multiple factors. To better understand related factors in the development of this disease, we focused on the mechanical stress loaded on articular cartilage.

Materials and Methods:

The anterior cruciate ligaments of rabbit knee joints were transected, and expression of protein kinase C (PKC) examined immunohistochemically. The PKC activator 12-o-tetradecanoyl-phorbol-13-acetate (TPA) was then administered intraarticularly. To determine the involvement of gas mediators, a cartilage defect was made on the medial femoral condyle of rabbit knee joints. Hydrostatic pressure was loaded on the cartilage taken from the surrounding defects, and levels of superoxide anion and nitric oxide (NO) were measured. Bovine chondrocytes were subjected to cyclic mechanical stretch using a Flexercell Strain Instrument. Proteoglycan synthesis and PKC activity were measured. Expression of matrix metal loproteinase (MMP)-3 and tissue inhibitors of metalloproteinase (TIMP)-1 in articular cartilages obtained from OA patients were examined using Northern blots.

Results:

Chondrocytes from experimentally induced OA were stained positively with anti-α-PKC antibody. Intraarticular administration of TPA prevented the development of OA changes. Cyclic tensile stretch loaded on chondrocytes decreased proteoglycan synthesis and PKC activity. Thus, PKC is involved in the stress-mediated degradation of articular cartilage. Cartilage defects led to degradation of surrounding cartilage and to enhanced superoxide anion and NO synthesis. We also noted increased and decreased expressions of MMP-3 and TIMP-1 mRNA in human OA cartilage, respectively.

Conclusion:

PKC, gas mediators (superoxide anion, NO), and proteinases are all involved in OA.     

Hepatitis C virus and hepatocellular carcinoma

The sequential development of cirrhosis and hepatocellular carcinoma (HCC) in patients with transfusion-associated hepatitis was a clue leading to the identification of hepatitis C virus (HCV) as a risk factor for HCC. The incidence of HCV-related liver cancer is increasing in many developed countries: tumours arise in older patients, are almost invariably associated with cirrhosis and often have a less aggressive course than is seen in HCC related to other aetiological factors. Most HCCs grow as a single hepatic nodule for several years before generating satellite or distant tumour nodules. Tumour progression and hepatic failure are the leading causes of death. HCV might promote cancer through cirrhosis, which is per se an important risk factor for this tumour. HCV might also have oncogenic properties by interacting with cellular genes that regulate cell growth and differentiation. The primary prevention of HCC through vaccination against HCV is not yet available. The treatment of patients with chronic hepatitis C with interferon might attenuate the risk of HCC.     

Anaesthesia for craniotomy

The aim of the neuroanaesthetist is to provide good operating conditions for the surgeon while protecting the brain from any physiological damage; a slack brain, maintenance of cerebral perfusion and reduction of cerebral metabolic rate. This is achieved by continual attention to basic details of technique and the application of methods based on an understanding of physiology, pharmacology and the pathological process. The development of new drugs, both inhalational, sevoflurane, and intravenous, propofol, alfentanil and remifentanil, given by infusion rather than boluses has enabled the anaesthetist to come closer to achieving the ideal. A better appreciation of post-operative pain and the effects of conventional analgesics, morphine and paracetamol will improve patient care. Morphine, which was previously considered to be contraindicated, is safe to use when given appropriately.     

Aging of the human synovium: An in vivo and ex vivo morphological study

Age-associated changes of the human synovium have been investigated by microarthroscopy, optical and electron microscopy, immunohistochemistry, and cytochemistry. The knee joints of nineteen 15- to 56-year-old subjects, classified as normal by inspection, were carefully examined by microarthroscopy; small synovial tissue biopsy specimens from both the suprapatellar pouch and the medial tibiofemoral gutter were taken. Microarthroscopy showed that the villi were more numerous and the vascular network and cell distribution and profiles less regular in aged individuals. These data were confirmed by scanning electron microscopy, which also showed large areas of the synovial surface devoid of cells and collagen bundles in contact with the joint cavity in aged subjects. Light and transmission electron microscopy confirmed these data and allowed evaluation of the number, distribution, shape, and internal organization of cells as well as the distribution of vessels and the organization of the extracellular matrix in the full thickness of the synovium (down to 2 mm). Particular attention was paid to synovial lining cells, among which three main phenotypes could be recognized: synthetic type (present at all ages and hypertrophied in aged subjects), macrophagelike (increasing with age), and fibroblastlike. Collagen increased with age. Further studies are needed for comprehensive understanding of age-associated changes in the human synovium.