Improvement of CPAP Therapy by a Self-Adjusting System

ABSTRACT

The first generation of Auto CPAP devices caused respiratory arousal by apnoes, hypopnoeas, incomplete obstructions and pressurechanges. The new, second generation of CPAP devices which is based on forced oscillation technique will change the pressure with slower velocity and before the respiratory arousal reaction will occur (1, 9, 10). Fifty patients with severe sleep apnoea (AHI 66±26 /h) were treated with both, constant- CPAP (continous positive airway pressure) or Auto CPAP under polysomnographic control in a randomised order. The Auto CPAP based on forced oscillation technique reduced the number of apnoeas and hypopnoeas as did most of the other Auto CPAP systems to AHI 2.5±5.9 /h (p<0.05). In comparison to Auto CPAP of the first generation it also decreased the number of respiratory arousal reactions caused by apnoeas and hypopnoeas. However there is still a significant difference to number of arousal detected with constant CPAP (p<0.01). In conclusion although the new generation of Auto CPAP reduced the number of respiratory arousals compared to first generation, we did not find a therapeutical benefit for patients with severe SAS.

KEYWORD

sleep apnoea syndrome - CPAP therapy - forced oscillation technique - self adjusting therapy

REFERENCES

• 1 Young T, Palta M, Dempsey J. The occurence of sleep disordered breathing among middle- aged adults.  New Engl J Med . 1993;  328 1230-1235
• 2 Strohl K P, Redline S. Recognition of obstructive sleep apnoea.  Am J Respir Crit Care Med . 1996;  154 279-289
• 3 Sullivan C, Berthon Jones M. Reversal of obstructive sleep apnoea by continous positive airway pressure through the nares.  Lancet . 1981;  1 862-865
• 4 Collard P, Pieters T, Aubert G. Compliance with nasal CPAP in obstructive sleep apnoea patients.  Sleep Medicine Reviews . 1997;  1 33-44
• 5 Fietze I, Bölcskei P L, Hörmann K. Komplikationen bei der nasalen CPAP Therapie- Konsequenzen für die Praxis.  Med Klinik . 1996;  91 758-765
• 6 Farre R, Rotger M, Montserrat J M. A system to generate simultaneous forced oscillation and continuous positive airway pressure.  Eur Resp J . 1997;  10 1349-1353
• 7 Series F Auto CPAP in the treatment of sleep apnoea hypopnoea syndrome. Sleep . 1996 19: 281-283
• 8 Pilz K, Meissner P, Thalhofer S, Dorow P. Auto-CPAP-verschiedene Systeme im Vergleich.  Somnologie . 1998;  2 15
• 9 Farre R, Peslin R, Rotger M. Inspiratory dynamic obstruction detected by forced oscillation during CPAP: a model study.  Am J Crit Care Med . 1997;  15 952-956
• 10 Navajas D, Farre R, Rotger M. Assessment of airway obstruction during CPAP by means of the forced oscillation technique in patients with SAS.  Am J Resp Crit Care Med . 1998;  157 1526-1530
• 11 Rechtschaffen A, Kales A. A Manual Standardized Terminology Techniques and Scoring System for Sleep Stages of Human Subjects.  Los Angeles: Brain Information Service, University of California; 1968
• 12 ASDA Atlas Task Force. Recording and scoring leg movements.  Sleep . 1993;  16 749-759
• 13 ASDA Task Force. EEG arousals: scoring rules and examples.  Sleep . 1992;  15 173-184
• 14 Meurice J C, Marc I. Series F. Efficiancy of Auto-CPAP in the treatment of obstructive sleep apnpa/hypopnea syndrome.  Am J Crit Care Med . 1996;  153 794-798
• 15 Teschler H, Berthon Jones M, Thompson A B. Automated continous positive airway pressure titration for obstructive sleep apnea syndrome.  Am J Respir Crit Care Med . 1996;  154 734-740