During adeno-tonsillectomies performed under general anaesthesia with N2O we observed and measured a serious increase in middle-ear pressure (M.E.P.). This is due to the fact that the rate of diffusion of N2O is greater inwards than outwards. This rise in the middle-ear pressure is due to the packing of the nasopharynx after adenoidectomy for haemostasis.

Otolaryngological complications occurred in 5 per cent of 467 patients with infectious mononucleosis admitted consecutively to the ENT-department during the period 1 April 1969 to 30 June 1981. Four patients had peritonsillar abscess and five patients developed potentially lethal obstruction of the upper airway. Such complications require intervention and, as the latter condition probably is the most frequent fatal complication of IM, we find it important that patients with even slight respiratory embarassment in infectious mononucleosis should be observed and treated in an ENT-department.

Twenty-four patients underwent crico-thyroidotomy at Guy's Hospital between 1977 and 1981. Of these, 13 died during admission or shortly after discharge as a result of their primary disease and three were unsuitable for further examination. The eight remaining patients were examined to assess the effect of crico-thyroideotomy on the laryngeal function of voice production. Assessment was made both subjectively and objectively by laryngography. Objective findings were correlated with structural changes seen by indirect laryngoscopy. Six of the eight patients examined had both subjective and objective disturbance of voice production. We report our experience with the surgical procedure of cricothyroidotomy which, in addition to a high incidence of vocal disturbance, includes one case of subglottic stenosis secondary to granulation tissue.