, Volume 193, Issue 3, pp 387–392 | Cite as

New Insights on the Pathophysiology of Inspiratory Flow Limitation During Sleep

  • Luciana B. M. de Godoy
  • Luciana O. Palombini
  • Fernanda L. Martinho Haddad
  • David M. Rapoport
  • Tatiana de Aguiar Vidigal
  • Priscila Calixto Klichouvicz
  • Sergio Tufik
  • Sonia M. TogeiroEmail author



Inspiratory flow limitation (IFL) is defined as a “flattened shape” of inspiratory airflow contour detected by nasal cannula pressure during sleep and can indicate increased upper airway resistance especially in mild sleep-related breathing disorders (SRBD). The objective of this study was to investigate the association between upper airway abnormalities and IFL in patients with mild SRBD.


This study was derived from a general population study consisting of selected individuals with apnea–hypopnea index (AHI) below 5 events/h of sleep, (“no obstructive sleep apnea” group) and individuals with AHI between 5 and 15 events/h (“mild obstructive sleep apnea” group). A total of 754 individuals were divided into four groups: group 1: AHI <5/h and <30 % of total sleep time (TST) with IFL (515 individuals), group 2: AHI <5/h and >30 % of TST with IFL (46 individuals), group 3: AHI: 5–15/h and <30 % of TST with IFL (168 individuals), and group 4: AHI: 5–15/h and >30 % of TST with IFL (25 individuals).


Individuals with complains of oral breathing demonstrated a risk 2.7-fold larger of being group 4 compared with group 3. Abnormal nasal structure increased the chances of being in group 4 3.2-fold in comparison to group 1. Individuals with voluminous lateral wall demonstrated a risk 4.2-fold larger of being group 4 compared with group 3.


More than 30 % of TST with IFL detected in sleep studies was associated with nasal and palatal anatomical abnormalities in mild SRBD patients.


Flow limitation Nasal cannula Sleep apnea Upper airway 



The authors would like to thank for the support by Grants from Associaçao Fundo de Incentivo a Pesquisa (AFIP), Fundaçao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq).

Conflict of interest



  1. 1.
    American Academy of Sleep Medicine (2014) The International classification of sleep disorders, 3rd edn. American Academy of Sleep Medicine, DarienGoogle Scholar
  2. 2.
    Hosselet JJ, Norman RG, Ayappa I et al (1998) Detection of flow limitation with a nasal cannula/pressure transducer system. Am J Respir Crit Care Med 57:1461–1467CrossRefGoogle Scholar
  3. 3.
    Remmers JE, DeGroot WJ, Sauerland EK (1978) Pathogenesis of upper airway occlusion during sleep. J Appl Physiol 44:931–938PubMedGoogle Scholar
  4. 4.
    Palombini LO, Tufik S, Rapoport DM et al (2013) Inspiratory flow limitation in a normal population of adults in São Paulo, Brazil. Sleep 36:1663–1668PubMedCentralPubMedGoogle Scholar
  5. 5.
    Tufik S, Santos-Silva R, Taddei JA, Bittencourt LR (2010) Obstructive sleep apnea syndrome in the Sao Paulo epidemiologic sleep study. Sleep Med 11:441–446CrossRefPubMedGoogle Scholar
  6. 6.
    Santos-Silva R, Tufik S, Conway SG et al (2009) Sao Paulo epidemiologic sleep study: rationale, design, sampling, and procedures. Sleep Med 10:679–685CrossRefPubMedGoogle Scholar
  7. 7.
    Rechtschaffen A, Kales A (1968) A manual of standardized terminology: techniques and scoring system for sleep stages of human subjects. UCLA Brain Information Service/Brain Research Institute, Los AngelesGoogle Scholar
  8. 8.
    Iber C, Ancoli-Israel S, Chesson AL Jr et al (2007) The AASM manual for the scoring of sleep and associated events: rules, terminology and technical specifications. American Academy of Sleep Medicine, WestchesterGoogle Scholar
  9. 9.
    American Academy of Sleep Medicine (2005) The International classification of sleep disorders: diagnostic & coding manual, 2nd edn. Academy of Sleep Medicine, WestchesterGoogle Scholar
  10. 10.
    Bao G, Guilleminault C (2004) Upper airway resistance syndrome – one decade later. Curr Opin Pulm Med 10:461–467CrossRefPubMedGoogle Scholar
  11. 11.
    Bittencourt LR (2008) Diagnosis and treatment of sleep obstructive apnea syndrome (OSAS): practical guide. Bookstore Paulista Medical Publisher, São PauloGoogle Scholar
  12. 12.
    Soares MC, Oliveira PW, Vidigal T et al (2010) Comparisons of the upper airway and facial skeleton of an adult population in the city of Sao Paulo with and without obstructive sleep apnoea. Sleep Res 19(Suppl 2):227Google Scholar
  13. 13.
    Ridley MB (1992) Aesthetic facial proportions. In: Papel ID, Nachlis NE (eds) Facial plastic and reconstructive surgery. St Louis, Mosby, p 106Google Scholar
  14. 14.
    Zonato AI, Bittencourt LR, Martinho FL et al (2003) Association of systematic head and neck physical examination with severity of obstructive sleep apnea-hypopnea syndrome. Laryngoscope 113:973–980CrossRefPubMedGoogle Scholar
  15. 15.
    Zonato AI, Martinho FL, Bittencourt LR et al (2005) Head and neck physical examination: comparison between nonapneic and obstructive sleep apnea patients. Laryngoscope 115:1030–1034CrossRefPubMedGoogle Scholar
  16. 16.
    Friedman M, Tanyeri H, La Rosa M et al (1999) Clinical predictors of obstructive sleep apnea. Laryngoscope 109:1901–1907CrossRefPubMedGoogle Scholar
  17. 17.
    Gold AR, Schwartz AR (1996) The pharyngeal critical pressure: the whys and hows of using nasal continuous positive airway pressure diagnostically. Chest 110:1077–1088CrossRefPubMedGoogle Scholar
  18. 18.
    Lee SH, Choi JH, Shin C et al (2007) How does open-mouth breathing influence upper airway anatomy? Laryngoscope 117(6):1102–1106CrossRefPubMedGoogle Scholar
  19. 19.
    Guilleminault C, Kirisoglu C, Poyares D et al (2006) Upper airway resistance syndrome: a long-term outcome study. J Psychiatr Res 40:273–279CrossRefPubMedGoogle Scholar
  20. 20.
    Guilleminault C, Lopes MC, Hagen CC et al (2007) The cyclic alternating pattern demonstrates increased sleep instability and correlates with fatigue and sleepiness in adults with upper airway resistance syndrome. Sleep 30:641–647PubMedGoogle Scholar
  21. 21.
    Calero G, Farre R, Ballester E et al (2006) Physiological consequences of prolonged periods of flow limitation in patients with sleep apnea hypopnea syndrome. Respir Med 100:813–817CrossRefPubMedGoogle Scholar
  22. 22.
    Edwards N, Blyton DM, Kirjavainen T et al (2000) Nasal continuous positive airway pressure reduces sleep-induced blood pressure increments in preeclampsia. Am J Respir Crit Care Med 162:252–257CrossRefPubMedGoogle Scholar
  23. 23.
    Ayappa I, Norman RG, Krieger AC et al (2000) Non-Invasive detection of respiratory effort-related arousals (RERAs) by a nasal cannula/pressure transducer system. Sleep 23:763–771PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Luciana B. M. de Godoy
    • 1
  • Luciana O. Palombini
    • 1
  • Fernanda L. Martinho Haddad
    • 1
    • 2
  • David M. Rapoport
    • 3
  • Tatiana de Aguiar Vidigal
    • 1
    • 2
  • Priscila Calixto Klichouvicz
    • 1
  • Sergio Tufik
    • 1
  • Sonia M. Togeiro
    • 1
    Email author
  1. 1.Disciplina de Medicina e Biologia do Sono, Departamento de PsicobiologiaUniversidade Federal de Sao PauloSao PauloBrazil
  2. 2.Departamento de Otorrinolaringologia e Cirurgia de Cabeça e PescoçoUniversidade Federal de Sao PauloSao PauloBrazil
  3. 3.Division of Pulmonary and Critical Care MedicineNew York University School of Medicine, NYCNew YorkUSA

Personalised recommendations