Cerebral venous and arterial blood gases during Cheyne-Stokes respiration

Gotoh, Fumio; Meyer, John Stirling; Takagi, Yasuyuki

doi:10.1016/0002-9343(69)90184-3

Cited by 25 publications

(12 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our findings provide support to the notion that ACZ ameliorates breathing pattern disturbances following ascent to high altitude (Weil et al 1978; Sutton et al 1979, 1980; Hackett et al 1987), independent of changes in either peripheral (Hackett et al 1987) or central chemoreflexes (Burki et al 1992). Furthermore, our findings corroborate with those of Gotoh et al (1969) who found that i.v . ACZ injection (500 mg) improved breathing stability by reducing the incidence of Cheyne–Stokes respiration cycles in patients with cerebrovascular disease.…”

Section: Discussionsupporting

confidence: 92%

Effects of acetazolamide on cerebrovascular function and breathing stability at 5050 m

Fan

Burgess

Thomas

et al. 2012

The Journal of Physiology

View full text Add to dashboard Cite

Key points• Acetazolamide improves breathing stability during sleep in newcomers to high altitude, but the mechanism remains unclear.• We examined the effects of a single I.V. dose of acetazolamide on brain vascular function and breathing at sea level and following 7 days at high altitude (5050 m).• We demonstrated that acute I.V. acetazolamide at high altitude enhances the brain blood flow response to changes in CO 2 and improves breathing stability.• We speculate that the enhanced brain blood flow responses following acetazolamide ingestion may account for the well-documented acetazolamide-induced improvement in abnormal breathing at high altitude.Abstract One of the many actions of the carbonic anhydrase inhibitor, acetazolamide (ACZ), is to accelerate acclimatisation and reduce periodic breathing during sleep. The mechanism(s) by which ACZ may improve breathing stability, especially at high altitude, remain unclear. We tested the hypothesis that acute I.V. ACZ would enhance cerebrovascular reactivity to CO 2 at altitude, and thereby lower ventilatory drive and improve breathing stability during wakefulness. We measured arterial blood gases, minute ventilation (V E ) and middle cerebral artery blood flow velocity (MCAv) before and 30 min following ACZ administration (I.V. 10 mg kg −1 ) in 12 healthy participants at sea level and following partial acclimatisation to altitude (5050 m). Measures were made at rest and during changes in end-tidal P CO 2 and P O 2 (isocapnic hypoxia). At sea level, ACZ increased resting MCAv and its reactivity to both hypocapnia and hypercapnia (P < 0.05), and lowered restingV E , arterial O 2 saturation (S a,O 2 ) and arterial P O 2 (P a,O 2 ) (P < 0.05); arterial P CO 2 (P a,CO 2 ) was unaltered (P > 0.05). At altitude, ACZ also increased resting MCAv and its reactivity to both hypocapnia and hypercapnia (resting MCAv and hypocapnia reactivity to a greater extent than at sea level). Moreover, ACZ at altitude elevated P a,CO 2 and again lowered resting P a,O 2 and S a,O 2 (P < 0.05). Although theV E sensitivity to hypercapnia or isocapnic hypoxia was unaltered following ACZ at both sea level and altitude (P > 0.05), breathing stability at altitude was improved (e.g. lower incidence of ventilatory oscillations and variability of tidal volume; P < 0.05). Our data indicate that I.V. ACZ elevates cerebrovascular reactivity and improves breathing stability at altitude, independent of changes in peripheral or central chemoreflex sensitivities. We speculate that P a,CO 2 -mediated elevations in cerebral perfusion and an enhanced cerebrovascular reactivity may partly account for the improved breathing stability following ACZ at high altitude.

show abstract

Section: Discussionsupporting

confidence: 92%

Effects of acetazolamide on cerebrovascular function and breathing stability at 5050 m

Fan

Burgess

Thomas

et al. 2012

The Journal of Physiology

View full text Add to dashboard Cite

show abstract

“…Some evidence suggests that hypocapnic alkalosis may play an important role. Respiratory alkalosis is typical in patients with classic Cheyne-Stokes breathing at low altitude (82). It also occurs in normal subjects in whom apneas during sleep commonly follow transient episodes of decreased endtidal PcOz and presumed increase in blood pH (31).…”

Section: Sleep At High Altitudementioning

confidence: 99%

Ventilatory Control at High Altitude

Weil

1986

Comprehensive Physiology

View full text Add to dashboard Cite

FIG. 2. Oxygen-tension (P4) cascade at low and high altitude.At high altitude, fall in P, for each step from tracheal or inspired air to venous circulation is decreased. One of the greatest decreases is that from inspired to alveolar air, which largely reflects increased ventilation at high altitude. [Adapted from Hurtado (105).] CHAPTER 21: VENTILATORY CONTROL AT HIGH ALTITUDE 705 /Y lr pace, pace, FIG. 3. Contrast of acid-base and oxygenation effects on ventilatory response to CO2. Acid-base alterations shift curve position (intercept) with little or no change in slope, whereas changes in O2 tension (P ) mainly influence the slope. P b , , arterial partial pressure of'%oz.

show abstract

“…The physiological interpretation of this observation must await additional observations in other patients. 8 This observation demonstrates one of the advantages of this method. A complete measurement can be made in a few seconds, while other methods applicable in man require several minutes for completion.…”

Section: Physiological Observationsmentioning

confidence: 63%

An Improved Thermal Dilution Method for Measuring Jugular Venous Flow

Halsey

1971

Stroke

View full text Add to dashboard Cite

An Improved Thermal Dilution Method for Measuring Jugular Venous Flow• The local thermal dilution method of performing serial bilateral measurements of internal jugular venous flow is significantly improved by injecting a bolus of saline rather than by using a continuous injection of saline. New thermistor catheter designs maintain the proper separation between the sites of injection and of sampling and require only a single insertion per side. The method measures mean flow rates over a two-second to three-second interval. Measurements were made in 14 patients with cerebrovascular disease. Studies of five patients are presented to illustrate the value of the method for assessing internal jugular venous hemodynamics. Positive response to injection of acetazolamide was noted in four of these five patients. Cyclic variations in jugular flow were observed in one patient with Cheyne-Stokes respiration. Occasional retrograde flow in one jugular vein was recorded in another patient.

show abstract

Cerebral venous and arterial blood gases during Cheyne-Stokes respiration

Cited by 25 publications

References 18 publications

Effects of acetazolamide on cerebrovascular function and breathing stability at 5050 m

Effects of acetazolamide on cerebrovascular function and breathing stability at 5050 m

Ventilatory Control at High Altitude

An Improved Thermal Dilution Method for Measuring Jugular Venous Flow

Contact Info

Product

Resources

About