The continuous laryngoscopy exercise test was easy to perform, well tolerated, and can be implemented in future diagnostic work-up programs of laryngeal dysfunction.

Variable obstruction to airflow at the laryngeal level may cause respiratory distress during exercise. The Continuous Laryngoscopy Exercise (CLE)-test enables direct visualization of the larynx during ongoing exercise. The aims of this study were to establish a scoring system for laryngeal obstruction as visualized during the CLE-test as well as to assess reliability and validity of this scoring system. Continuous video recording of the larynx was performed in parallel with continuous video recording of the upper part of the body, and recording of breath sounds in 80 patients and 20 symptom-negative volunteers, running on a treadmill to respiratory maximal tolerable distress or exhaustion. Each participant scored the degree of symptoms during exercise. The scoring system contains four sub-scores, each graded from 0 to 3. Two independent laryngologists, blinded to clinical data, scored the video recordings of the larynx twice. The proportion of inter- and intra-observer agreement (equal scores) for each sub-score through these four sessions varied between 70 and 100% (weighted kappa values varied from 0.49 to 1.00 correspondingly). A positive correlation was found between CLE-test sum score and symptom score (rho = 0.75, P < 0.001). There was a significant difference in CLE-test sum score between patients (3.34 +/- 1.34) and volunteers (0.65 +/- 0.66) (P < 0.001). The single CLE-test sub-score that correlated most strongly with symptom score was glottic adduction at maximal effort (rho = 0.75, P < 0.001). The presented scoring system is reliable and valid, and we suggest that it can be used when laryngeal function during exercise is evaluated.

Larynx can safely be studied throughout a maximum intensity exercise treadmill test. A characteristic laryngeal response pattern to exercise was visualised in a large proportion of patients with suspected upper airway obstruction. Laryngoscopy during ongoing symptoms is recommended for proper assessment of these patients.

Asthma-like symptoms and airway hyper-responsiveness (AHR) are frequently reported in children subsequent to premature birth and bronchopulmonary dysplasia (BPD). There is limited knowledge on the mechanisms underlying these respiratory manifestations. Generally, childhood asthma and AHR is described within a context of inheritance, allergy and eosinophilic airway inflammation, and often in relation to cigarette exposures. We investigated these factors in relation to current asthma and AHR in a population-based cohort of 81 young people, born with gestational age < or = 28 wk or birth weight < or = 1000 g, and in a matched term-born control population. In the pre-term population, asthma and AHR were additionally studied in relation to neonatal respiratory morbidity. At follow up, more pre-term than control subjects had asthma. Forced expiratory volume in first second (FEV1) was reduced, AHR was substantially increased, and the level of the urinary leukotriene metabolite E4 (U-LTE4) was increased in the pre-term population compared to the term-born. In control subjects, asthma and AHR was associated with a pattern consistent with inheritance, allergy, airway inflammation, and cigarette exposures. In the pre-terms, asthma and AHR was either unrelated or less related to these factors. Instead, AHR was strongly related to a neonatal history of BPD and prolonged requirement for oxygen treatment. In conclusion, asthma and AHR subsequent to extremely premature birth differed from typical childhood asthma with respect to important features, and AHR was best explained by neonatal variables. These respiratory manifestations thus seem to represent a separate clinical entity.

The proportion of prone sleeping among sudden infant death syndrome (SIDS) victims and infants in general, and the rate of SIDS were prospectively studied in the county of Hordaland, Norway, three years before (1987-89) and three years after (1990-92) a campaign to discourage prone sleeping. Before the campaign, 64% of random reference infants were put prone versus 8% after (p < 0.0001). Concurrently, the rate of SIDS decreased from 3.5 to 1.6 per 1000 live births (63 infants before and 30 after the campaign, p = 0.0002). Prone sleeping was not considered a statistically significant risk factor for SIDS before (OR 2.0, 95% CI 0.8-4.5), but was highly significant (OR 11.3, 95% CI 3.6-36.5) after the campaign. Prone sleeping is an important risk factor for SIDS, but the association may be missed in epidemiological studies if prone is the predominant sleeping position. Behaviour with regard to sleeping position may be changed rapidly by means of a simple campaign.

A method for combined ergo-spirometry and continuous laryngeal inspection during exercise, entitled continuous laryngoscopy exercise test (CLE-test) has been developed in order to study airway obstruction at the laryngeal level during exercise. The aim of the study was to apply the CLE-test on patients experiencing respiratory distress during exercise in order to reveal the usefulness of the CLE-test both as a diagnostic tool in the selection of patients for surgery and in evaluation of treatment effects postoperatively. Until now, 81 patients with a history of exercise-induced stridor have undergone the CLE-test. Ten of these patients were selected for surgical treatment based on the severity of symptoms and their motivation for treatment. All ten patients underwent endoscopic supraglottoplasty (ES), with laser incision in both aryepiglottic folds anterior to the cuneiform cartilages and removal of the mucosa around the top of the tubercles. Each patient was examined by the CLE-test before and 3 months after surgery. Eight patients felt subjectively that their breathing capacity during exercise was improved. When pre- and postoperative ergo-spirometry evaluations were compared, increased peak oxygen consumption was observed in four out of ten patients and better maximal minute ventilation in seven out of ten. Postoperative evaluation of the laryngeal images showed less prominent aryepiglottic folds. The typical adduction of the supraglottic structures concomitant with inspiratory stridor found preoperatively was not present in any of the patients during exercise postoperatively. The ES procedure is an efficient surgical treatment for exercise-induced laryngeal supraglottic obstruction and the CLE-test eases the selection of patients for surgery and facilitates the evaluation of treatment effects.

Aims-To study the eVect of prone and supine sleep on infant behaviour, peripheral skin temperature, and cardiorespiratory parameters to aid understanding of why prone sleeping is associated with an increased risk of sudden infant death syndrome. Methods-Of 33 enrolled infants, 32 were studied at 2.5 and 28 at 5 months of age. A computer aided multichannel system was used for polysomnographic recordings. Behaviour was charted separately. Results-Prone REM (active) sleep was associated with lower frequencies of short arousals, body movements and sighs, and a shorter duration of apnoeas than supine REM sleep at both ages. At 2.5 months there were less frequent episodes of periodic breathing during prone sleep in non-REM (quiet) and REM sleep. Heart rate and peripheral skin temperature were higher in the prone position during both sleep states at both ages. Conclusions-The observation of decreased variation in behaviour and respiratory pattern, increased heart rate, and increased peripheral skin temperature during prone compared with supine sleep may indicate that young infants are less able to maintain adequate respiratory and metabolic homoeostasis during prone sleep. (Arch Dis Child 1997;76:320-324) Keywords: behaviour; sudden infant death syndrome; sleeping position Prone sleeping, overwrapping, heating of the bedroom, and other infant care practices which may increase body temperature are reported risk factors for sudden infant death syndrome (SIDS).1-4 There seems to be a causal relation between prone sleeping and SIDS, but the terminal, pathophysiological mechanisms causing death are largely unknown. Lack of a normal arousal response 5 or suVocation due to airway obstruction or rebreathing of carbon dioxide from a face down position [6][7][8][9][10] have been suggested as contributory mechanisms. Although epidemiological studies have shown that there is an association between overwrapping and increased environmental temperature, and SIDS, the mechanisms of interaction are not understood.2 4 The issue is complicated further as overheating seems to be a risk factor particularly or exclusively for infants sleeping prone. 4The purpose of the present study was to compare supine and prone sleeping in early infancy with respect to sleep related behaviour, peripheral body temperature, and cardiorespiratory responses in a warm environment to add understanding to why prone sleeping is a major risk factor for SIDS. Subjects and methods SUBJECTSThirty three infants (17 girls and 16 boys) were recruited for an overnight sleep study. Only term infants (at least 37 weeks' postconceptional age) without prenatal or perinatal complications were included. No infant with a positive history of family diseases, apparently life threatening events, or cases of SIDS in siblings was allowed. The mean birth weight was 3631 g (range 2870-4840 g) and all infants were healthy at the time of the study.A questionnaire containing information on infant care practices such as feeding, preferred sleeping position, sleep environment, ...

Preterms born in different eras of neonatology had similar long-term decreases in lung function. Long periods of oxygen supplementation are still required to salvage immature infants, and airway obstruction may still be a common long-term outcome.