title: The air hunger response of four elite breath-hold divers.
abstract: Normal subjects terminate breath-holds due to intolerable 'air hunger'. We hypothesize that competitive breath-hold divers might have increased tolerance of air hunger. We tested the air hunger (AH) response of four divers who could hold their breath for 6-9 min. Tidal volume and respiratory rate were controlled by mechanical ventilation (ventilation approximately 0.16 L min(-1) kg(-1)). AH was induced by raising PCO2 and rated using a visual analog scale whose maximum was defined as intolerable. SpO2 was maintained at >97%. Three divers reported the same uncomfortable urge to breathe as normal subjects; the slopes of their responses were within normal range. Both resting CO2 and AH threshold were shifted to higher CO2 in some divers. Diver 3 was unique amongst neurologically intact subjects we have studied: he denied feeling an urge to breathe, and denied discomfort. We conclude that elite divers' strategies to tolerate intense air hunger are a minor factor in their ability to tolerate long breath-holds.
authors: Physiology Program, Department of Environmental Health, Harvard School of Public Health, and Department of Anesthesiology, Brigham & Women's Hospital, Boston, MA, USA. abinks@une.edu
authors: Andrew P
authors: AP
authors: Binks
authors: Andrea
authors: A
authors: Vovk
authors: Massimo
authors: M
authors: Ferrigno
authors: Robert B
authors: RB
authors: Banzett
mesh_terms: D000328:Adult; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000378:metabolism; D004242:Diving / Q000502:physiology*; D004417:Dyspnea / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D010313:Partial Pressure; D012123:Pulmonary Ventilation / Q000502:physiology; D012119:Respiration; D012121:Respiration, Artificial / Q000379:methods; D015656:Respiratory Mechanics / Q000502:physiology*; D012677:Sensation / Q000502:physiology; D013990:Tidal Volume / Q000502:physiology; D013997:Time Factors; D014939:Work of Breathing
chemical_list: D002245:Carbon Dioxide
references: J Appl Physiol (1985). 2007 Mar;102(3):841-6
references: 17110514
references: Respir Physiol. 1996 Jan;103(1):19-31
references: 8822220
references: Exp Physiol. 2000 Nov;85(6):847-56
references: 11187979
references: Respir Physiol. 1994 Jan;95(1):53-66
references: 8153453
references: Clin Sci (Lond). 1996 Dec;91(6):755-61
references: 8976812
references: J Appl Physiol (1985). 1995 Dec;79(6):2169-76
references: 8847288
references: J Appl Physiol (1985). 1996 Aug;81(2):949-56
references: 8872667
references: Brain Res. 1986 Feb 26;366(1-2):238-53
references: 3697681
references: Respir Physiol. 1989 Apr;76(1):53-67
references: 2499025
references: J Appl Physiol. 1974 Sep;37(3):291-6
references: 4415069
references: Can J Anaesth. 1990 Nov;37(8):933-42
references: 2123750
references: J Appl Physiol (1985). 2003 Jan;94(1):141-54
references: 12391041
references: Respir Physiol. 1992 Oct;90(1):31-46
references: 1455097
references: Trans Am Clin Climatol Assoc. 1954;66:116-25
references: 13256580
references: Respir Physiol Neurobiol. 2003 Mar 3;134(2):77-83
references: 12609476
references: J Neurophysiol. 2002 Sep;88(3):1500-11
references: 12205170
references: Fed Proc. 1981 Jul;40(9):2365-71
references: 7250381
references: Respir Physiol. 1994 Aug;97(3):323-32
references: 7973136
references: Eur J Appl Physiol. 2006 May;97(2):158-64
references: 16525813
references: J Physiol. 1908 Jun 30;37(2):77-111
references: 16992924
references: Australas Ann Med. 1967 Feb;16(1):20-32
references: 6032026
references: Respir Physiol. 1993 Aug;93(2):203-19
references: 8210759
references: Respir Physiol. 2000 Mar;120(1):13-26
references: 10786641
references: Jpn J Physiol. 1982;32(3):327-36
references: 7131933
references: Anesthesiology. 1959 Nov-Dec;20:789-98
references: 13825447
references: J Appl Physiol (1985). 2006 Sep;101(3):799-801
references: 16690794
references: Eur J Appl Physiol. 2005 Aug;94(5-6):646-51
references: 15942772
references: Respir Physiol Neurobiol. 2003 Aug 14;137(1):1-10
references: 12871672