SOME EFFECTS OF THE AMINOGLYCOSIDE ANTIBIOTIC AMIKACIN ON NEUROMUSCULAR AND AUTONOMIC TRANSMISSION

The effects of the new aminoglycoside antibiotic amikacin onneurohumoral transmission were tested in the anaesthetized cat,and in mouse, rat and chick isolated nerve-muscle preparations.Amikacin had blocking actions on both autonomic and neuromusculartransmission. The autonomic effects were caused mainly by ganglionblockade and were reversed by calcium. The amikacin-inducedneuromuscular blockade resulted from a decreased release ofacetylcholine and a reduced postjunctional sensitivity. Intracellularrecording from end-plates in the rat diaphragm demonstratedthat amikacin had magnesium-like effects on acetylcholine release.The blockade was reversed completely by calcium, 4-aminopyridineand 3, 4-diaminopyridine and partially by neostigmine. The neuromusculareffects of amikacin in vivo were augmented greatly after pretreatmentwith tubocurarine. It is concluded that care should be exercisedif amikacin is administered during surgery in conjunction withtubocurarine.     

Anaesthetic management of insulinoma

The anaesthetic management of two cases of insulinoma treated by distal pancreatectomy is presented. Stress is laid on pre-operative and intra-operative glucose administration in sufficiently high quantity. Pre-operative corticosteroid therapy is better avoided. Dextrose infusion should be stopped soon after removal of the tumour to prevent excessive hyperglycemic response in the postoperative period. Methyoxyflurane was used because it tends to raise the blood sugar level. Pancuronium bromide was preferred because of the stable cardiovascular conditions it produces.     

Management of Post-cricoid carcinoma

This paper discusses the results of treatment of post-cricoid carcinoma based on a personal series of 141 patients. The following conclusions can be drawn: small tumours with no clinical evidence of cervical lymph node metastasis should almost certainly be treated with radiotherapy, which gives a 5-year survival of approximately 35%. Surgery for recurrent disease after radiotherapy is fraught with complications, and satisfactory salvage is seldom possible. Surgery for larger tumours and those associated with neck node metastases has a lower (20%) 5-year survival with a high incidence of complications. The main problem after pharyngolaryngectomy is replacement of the pharynx. There is no evidence that any one of the methods in common use (skin flaps, transposition of the colon or stomach) is superior to any other.     

Modified polyalkenoate (glass-ionomer) cement – a study

summary Conventional glass-ionomer cements with varying amounts (5–15%) of borax (Na₂B₄O₇.10H₂O) as modifier were prepared. These mixtures were spatulated with an aqueous solution of polyacrylic acid with a powder to liquid (P/L) ratio of 1.5:1. Properties such as working time, setting time, compressive strength, diametral tensile stength, solubility and fluoride release of these cements were determined. It was observed that the working time and setting time of the resultant cements shortened with the addition of borax. Certain physical properties such as compressive and diametral tensile strength, solubility and disintegration of these glass-ionomer cements deteriorated with borax addition but fluoride release from them was unaffected.