High-Frequency Positive-Pressure Ventilation (HFPPV) During Transthoracic Resection of Tracheal Stenosis and During Peroperative Bronchoscopic Examination

Operation of a patient with intrathoracic tracheal stenosis using a new ventilation technique (HFPPV) is described. The technique permits tracheoscopy during ventilation and operation, thus enabling exact location of the stenosis to be obtained. Further, peroperative tracheoscopic checking of the anastomosis can be carried out. Resection and anastomosis can be performed without interference of a bulky endotracheal tube.  

ZUSAMMENFASSUNG

Es wird die Operation eines Patienten mit intrathorakaler Trachealstenose beschrieben, bei der eine neue Beatmungstechnik (HFPPV = hochfrequente Überdruck-Ventilation) angewandt wurde. Die Methode ermöglicht unter gleichzeitiger Beatmung eine tracheoskopische genaue Lokalisation der Stenose. Ferner kann während der Operation die Anastomose tracheoskopisch kontrolliert werden. Resektion und Anastomose können ohne Beeinträchtigung durch einen dicken Endotrachealtubus vorgenommen werden.     

Treatment of craniopharyngiomas — the stereotactic approach in a ten to twenty-three years' perspective

Summary A multi-modality treatment programme, where stereotactic methods were used preferentially, gave results in a consecutive series of craniopharyngiomas, not inferior to those reported after microsurgical removal. Fourty-two patients with a follow-up range of 10–23 years are reported.     

Plexiform fibrohistiocytic tumor. Report of a case involving preoperative aspiration cytology and immunohistochemical and ultrastructural analysis of surgical specimens.

A typical case of plexiform fibrohistiocytic tumor (Enzinger and Zhang) occurring in the skin and subcutis of the abdominal wall in a 7-year-old girl is reported. Preoperative fine-needle aspiration cytology revealed a benign lesion with fibroblastic-histiocytic features which also contained bi- and multinucleated giant cells. The surgical specimen showed a tumor with multiple small nodules within fibrous septa; these nodules were composed of spindle cells and epithelioid cells and contained scattered multinucleated osteoclast-like cells. The tumor cells showed ultrastructural and immunohistochemical features of myofibroblasts and histiocyte-like cells. Thus, there was an abundance of lysosomes, prominent filopodia and bundles of thin cytofilaments along the cytoplasmic border, as well as immunoreactivity for alpha-smooth-muscle-specific actin, alpha-1-antitrypsin and alpha-1-antichymotrypsin. Ultrastructurally there were tumor cells exhibiting features of histiocytes which also contained bundles of actin of smooth muscle type. The presented case of plexiform fibrohistiocytic tumor appears to be composed of a rather peculiar cell form, somewhere between myofibroblasts and histiocytes.     

Effects of chronic beta-adrenoceptor antagonism on plasma catecholamines and blood pressure in hypertension

Plasma catecholamines were measured before and after treatment with beta-adrenoceptor antagonists in 17 hypertensive patients. Chronic treatment with beta-adrenoceptor antagonists caused substantial reductions in heart rate and intra-arterial blood pressure recorded continuously during ambulation. Before treatment, a quantitative relationship was observed between plasma norepinephrine and blood pressure and heart rate during a variety of activities; a similar relationship was also observed after chronic treatment five of six patients, suggesting that plasma norepinephrine remains an index of sympathetic activity despite the influence of beta-adrenoceptor antagonism. After treatment, plasma norepinephrine tended to be higher at any level of blood pressure, although not significantly so. Chronic treatment caused no significant change in mean resting plasma levels of norepinephrine and epinephrine. During exercise, plasma norepinephrine and epinephrine levels were significantly elevated above control after acute but not after chronic treatment. These observations do not support the hypothesis that beta-adrenoceptor antagonist drugs lower blood pressure in hypertensive man through a sympatholytic mechanism in he central nervous system or at peripheral presynaptic receptors.     

Influence of supply of heat to cobalt-chromium frameworks during soldering and subsequent hardening heat treatment of wrought clasps

Retentive clasp arms of wrought gold alloy wire were soldered to frameworks made of three dental cobalt-chromium alloys. The clasps were then subjected to a conventional hardening heat treatment. Microstructure and hardness of the cobalt-chromium alloys were determined before and after these operations. The results reveal that the supply of heat during soldering and hardening heat treatment of the clasp does not influence the microstructure and hardness of the cobalt-chromium alloys.     

Experimental Cutaneous Pain Thresholds and Tolerance in Clinical Analgesia with Epidural Morphine

Ten patients experiencing significant analgesia from repealed low-dose morphine injections via an indwelling epidural catheter were studied. One group (n=5) with acute, postoperative pain was tested for changes in experimental cutaneous pain thresholds with and without clinical morphine analgesia. Three of these patients received intravenous naloxone. The analgesia was reversed in two. There was no significant alteration in any cutaneous modality, including pain, although the postoperative deep pain was relieved. This discrepancy might be explained by the existence of separate subpopulations of opiate receptors at the spinal cord level, which differentiate nociceptive input from the skin and from deep body structures. The other group (n = 5) of cancer pain patients with a permanent epidural catheter was monitored for long-term changes in clinical pain. Signs of tolerance were not seen with an observation period up to 6 weeks.     

Verifying copper toxicosis in Bedlington terriers by analytical electron microscopy of needle biopsies of liver

Diagnosis of copper toxicosis in Bedlington terriers was performed by analytical electron microscopy of needle biopsy of the liver. The animals were four Bedlington terriers clinically suspected of hereditary copper toxicosis, and four healthy control animals of the same breed. Light microscopy of the livers of the diseased animals revealed dense bodies in the hepatocytes which stained histochemically for copper. Analytical electron microscopy showed that the intrahepatocytic bodies consisted almost entirely of copper.