R. Haidmayer

Statistical evaluation of respiratory control in infants to assess possible risk for the sudden infant death syndrome (SIDS)

We examined the application of statistical parameters related to respiratory control in order to assess possible risk for the sudden infant death syndrome (SIDS). The suitability of these parameters was tested in 287 infants between 1 day and 6 months of age. Respiration of the infants was recorded during sleep, and duration and frequency of apneic spells was evaluated. All infants were patients of the department of pediatric surgery, and were free of pulmonary, cardiac or cerebral diseases. Of the investigated infants, 54 were assigned as an at risk group, for they had already had demonstrable serious or life threatening apneas or respiratory problems during anesthesia.We computed the frequency distribution of sleep apnea durations, and calculated the respective probabilities for the occurrence of apnea of a certain duration according to age. By analogy with Shannons well known definition of average information content we defined an entropy term, which formally agrees with the definition of entropy in thermodynamics. This statistical procedure seems to be well suited for the identification of disorders in respiration control possibly related to a risk for SIDS. All at risk infants were treated with aminophylline, and the respiratory state improved significantly in nearly all cases.In some infants QT intervals were evaluated from the ECG recordings during sleep, but no significant differences between risk and control infants could be demonstrated.

Physiological and clinical aspects of respiration control in infants with relation to the sudden infant death syndrome

SummaryWe have examined the behavior of several variables which are related to respiratory control in 114 infants (up to 6 months of age) in order to assess the risk for the sudden infant death syndrome (SIDS). 23 of the infants had already had demonstrable serious or life threatening apneas or respiratory problems during surgical anesthesia. These infants were assigned as a risk group, and the rest of the investigated babies was taken as a control group.We found that practically all infants of the risk group had apneas during sleep, which lasted longer than 8 s each. Only 22% of the infants of the control group had apneas of such a duration. As a statistical parameter, calculated from at least 1 hour recording of respiration, we defined the mean apnea duration (MA-value) as average value of apnea duration time in seconds per minute of recording. The MA-value proved to be significantly elevated in the infants of the risk group. The trend to hypoxia in the infants of the risk group was also indicated by the observation of lower transcutaneous

Effects of naloxone on apnoea duration during sleep in infants at risk for SIDS

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COMPUTER-BASED SLEEP MONITORING IN SIDS-RISK INFANTS - PRELIMINARY RESULTS

-values (tc-

Das moderne Schlaflabor bei Diagnose und Therapie von nächtlichen Atemstörungen

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Assessment of Possible Risk for the Sudden Infant Death Syndrome (SIDS) Based on the Evaluation of Respiratory Pattern and Ventilatory Controll Mechanisms

) during sleep, when compared with control infants. In agreement with this observation is the increase of the 2,3-DPG concentration and the decrease of the density of erythrocytes of the infants of the risk group.Breathing hypoxic gas mixtures tended to depress respiration in all infants tested, and, especially in the risk group, to elicit irregular respiratory patterns. On the other hand, we observed that inhalation of pure oxygen markedly stimulated respiration in all infants investigated.We conclude from these observations that a risk for SIDS may be related to a particular response pattern of the respiratory center during the early postnatal life. We are able to distinguish infants with a higher risk for SIDS from other children by determination of the MA-value during sleep.ZusammenfassungWir untersuchten das Verhalten verschiedener Variabler, die mit der Atemregulation bei Säuglingen bis zu einem Alter von 6 Monaten in Verbindung stehen, um ein eventuelles Risiko für das Auftreten eines SIDS-Ereignisses (sudden infant death syndrome) identifizieren zu können. Bei 23 von insgesamt 114 untersuchten Säuglingen waren bereits ernste oder lebensbedrohende Apnoeanfälle während chirurgischer Eingriffe unter Narkose beobachtet worden. Diese Babies wurden als Risikogruppe bezeichnet, während die restlichen untersuchten Säuglinge als Kontrollgruppe galten.Wir konnten zeigen, daß praktisch alle Risikosäuglinge Apnoen während des Schlafes hatten, die eine Länge von 8 s überschritten. Lediglich 22% aller Kontrollsäuglinge hatten Apnoen dieser Länge. Von den aufgezeichneten Atemkurven berechneten wir als statistischen Parameter den mittleren Atemsausfall in s pro min (MA-Wert). Dieser MA-Wert war bei der Risikogruppe im Vergleich mit der Kontrollgruppe statistisch signifikant erhöht. Durch kontinuierliche Aufzeichnungen der transkutanen