Perilymph fistulas: the House Ear Clinic experience

The diagnosis, evaluation, and surgical treatment of perilymph fistulas has recently been the focus of a great deal of attention in otology. Authors have focused on perilymph fistulas as the cause of hearing loss and vertigo in many diverse situations. Additionally, surgical repair has been suggested when there is little objective support for intervention. To address some of the problems inherent in the diagnosis and treatment of perilymph fistulas, records of patients operated on at the House Ear Clinic during the past 12 years were reviewed retrospectively. Eighty-six patients were surgically explored for fistulas during this period. Thirty-five (40.7%) fistulas were found, and 51 ears were patched whether fistulas were found or not. Of the 80 patients who were seen for follow-up, 35 (43.8%) were subjectively better, and 45 (56.2%) were the same. Although the number of fistulas found and the number of patients improved were similar, the composition of the two groups was different. On the basis of audiometric results, improvement in hearing occurred in only 18.7% of the patients. None of the demographic factors or diagnostic tests were predictive of either the presence of a fistula or the therapeutic outcome. Further work is required to facilitate the preoperative diagnosis of fistulas and to design appropriate surgical intervention.     

Anuria in infants and children

The urologist may be involved in the initial evaluation of a child with anuria. In our experience the most common cause of anuria in neonates was perinatal hypoxia and in older children it was the hemolytic uremic syndrome. Obstructive uropathy as a cause of anuria in infants and children appears to be uncommon.     

Hypertension in infants and children

This is a review of selected aspects of hypertension in infants and children. The causes of pediatric hypertension are discussed. The role of diet in the etiology and/or treatment of hypertension is examined. Following a discussion of the morbidity and mortality of hypertension, aspects of the treatment of chronic hypertension are presented. Finally, a series of patients seen by our service with malignant hypertension is reported.     

Mivacurium in infants and children

Mivacurium is the only available short-acting nondepolarizing muscle relaxant in clinical use. It is a bis-quaternary benzylisoquinolinium ester hydrolysed by plasma-cholinesterase into inactive compounds. The ED₅₀ and ED₉₅ in children are about 50 μg·kg^?1 and 90 μg·kg^?1 respectively. In infants, they have a tendency to be lower. A standard intubating dose of 0.25 mg·kg^?1 causes complete neuromuscular depression in 1.5–2 min, recovery to 5% in 6–10 min, and complete recovery in 15–20 min. The recent tendency is to use 0.3 mg·kg^?1 to obtain better intubating conditions with slight prolongation of effect. Since the recovery profile of mivacurium is independent of the dose and duration, it is most suitable for administration by continuous infusion. The infusion requirement in children is 10–16 μg·kg^?1 min^?1, which is about twice that of adults. Cutaneous flushes from histamine release are commonly seen with the larger doses of mivacurium; however, the associated hypotensive effects are minimal and counteracted by the tracheal intubation. The duration of action of mivacurium is prolonged in patients with cholinesterase deficiency. Mivacurium's neuromuscular effects can be satisfactorily antagonized by edrophonium or neostigmine.