Philip N. Ainslie
University of British Columbia
Internal medicineEndocrinologyCerebral perfusion pressureCerebral blood flowBlood flowCardiologyHemodynamicsChemistryTranscranial DopplerMiddle cerebral arteryMean arterial pressureHypercapniaHeart rateHypocapniaHypoxia (medical)AnesthesiaMedicineOrthostatic vital signsEffects of high altitude on humansCerebral autoregulationBlood pressure
Publications 277
#1Christine M. Tallon (UBC: University of British Columbia)H-Index: 4
#2Kurt J. Smith (UVic: University of Victoria)
Last. Ali M. McManus (UBC: University of British Columbia)H-Index: 5
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We explored the influence of sex and maturation on resting cervical artery hemodynamics (common carotid artery, CCA; internal carotid artery, ICA; and vertebral artery, VA) and free-living physical...
#1Jeremy J. Walsh (UBC: University of British Columbia)H-Index: 12
#2Hannah G. Caldwell (UBC: University of British Columbia)H-Index: 6
Last. Jonathan P. Little (UBC: University of British Columbia)H-Index: 51
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Adults with obesity are at increased risk of neurocognitive impairments, partly as a result of reduced cerebral blood flow and brain-derived neurotrophic factor (BDNF). Ketone supplements containing β-hydroxybutyrate (β-OHB) are a purported therapeutic strategy for improving brain health in at-risk populations. We tested the hypothesis that short-term β-OHB supplementation will elevate cerebral blood flow and BDNF, as well as improve cognition in adults with obesity. In a placebo-controlled doub...
#1Hannah J. Thomas (UWA: University of Western Australia)H-Index: 3
#2Channa E. Marsh (UWA: University of Western Australia)H-Index: 3
Last. Daniel J. Green (UWA: University of Western Australia)H-Index: 88
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Aim: It is generally considered that regular exercise maintains brain health and reduces the risk of cerebrovascular diseases such as stroke and dementia. Since the benefits of different 'types' of...
#1Alexander Patrician (UBC: University of British Columbia)H-Index: 8
#2Tony G. Dawkins (Cardiff Metropolitan University)H-Index: 5
Last. Kaitlyn Tymko (UBC: University of British Columbia)
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Abstract null null Background null Increasing iron bioavailability attenuates hypoxic pulmonary vasoconstriction in both lowlanders and Sherpa at high altitude. In contrast, the pulmonary vasculature of Andeans suffering with chronic mountain sickness is resistant to iron administration. While pulmonary vascular remodeling and hypertension are characteristic features of chronic mountain sickness, the impact of iron administration in healthy Andeans has not been investigated. If the interplay bet...
#1Mike Stembridge (Cardiff Metropolitan University)H-Index: 15
#2Ryan L. Hoiland (UBC: University of British Columbia)H-Index: 20
Last. James D. Anholm (LLU: Loma Linda University)H-Index: 13
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Haemoconcentration can influence hypoxic pulmonary vasoconstriction (HPV) via increased frictional force and vasoactive signalling from erythrocytes, but whether the balance of these mechanism is m...
#1Ryan L. HoilandH-Index: 20
#2Philip N. Ainslie (UBC: University of British Columbia)H-Index: 65
Last. David K. Menon (University of Cambridge)H-Index: 116
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Rationale: Secondary brain hypoxia portends significant mortality in ischemic brain diseases, yet our understanding of hypoxic ischemic brain injury (HIBI) pathophysiology in humans remains rudimentary. Objective: To quantify the impact of secondary brain hypoxia on injury to the neurovascular unit in patients with HIBI. Methods and Results: We conducted a prospective interventional study of invasive neuromonitoring in 18 post-cardiac arrest patients with HIBI. The partial pressures of brain tis...
2 CitationsSource
#1Andrew R. Steele (U of A: University of Alberta)H-Index: 4
#2Michael M. Tymko (U of A: University of Alberta)H-Index: 2
Last. Rómulo Figueroa-Mujíca (UPCH: Cayetano Heredia University)H-Index: 4
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The high-altitude maladaptation syndrome known as chronic mountain sickness (CMS) is characterized by polycythemia and is associated with proteinuria despite unaltered glomerular filtration rate. H...
#1Hannah G. Caldwell (UBC: University of British Columbia)H-Index: 6
#2Connor A. Howe (UBC: University of British Columbia)H-Index: 10
Last. Thompson G. Robinson (University of Leicester)H-Index: 58
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KEY POINTS We investigated the influence of arterial PCO2 (PaCO2 ) with and without acute experimental metabolic alkalosis on neurovascular coupling (NVC). We assessed stepwise iso-oxic alterations in PaCO2 prior to and following intravenous sodium bicarbonate (NaHCO3- ) to acutely elevate arterial pH and bicarbonate ([HCO3- ]). The NVC response was not altered following NaHCO3- between stepwise PaCO2 stages; therefore, NVC is acutely mediated by PaCO2 rather than the prevailing arterial [H+ ]/p...
#1Nicholas FergussonH-Index: 10
#2Ryan L. HoilandH-Index: 20
Last. Mypinder S. SekhonH-Index: 22
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PURPOSE Following return of spontaneous circulation after cardiac arrest, hypoxic ischemic brain injury is the primary cause of mortality and disability. Goal-directed care using invasive multimodal neuromonitoring has emerged as a possible resuscitation strategy. We evaluated whether goal-directed care was associated with improved neurologic outcome in hypoxic ischemic brain injury patients after cardiac arrest. DESIGN Retrospective, single-center, matched observational cohort study. SETTING Qu...
2 CitationsSource
#1Patrice Brassard (Laval University)H-Index: 13
#2Lawrence Labrecque (Laval University)H-Index: 6
Last. Philip N. Ainslie (UBC: University of British Columbia)H-Index: 65
view all 10 authors...
In 1959, Niels Lassen illustrated the cerebral autoregulation curve in the classic review article entitled Cerebral Blood Flow and Oxygen Consumption in Man. This concept suggested a relatively broad mean arterial pressure range (~60-150 mmHg) wherein cerebral blood flow remains constant. However, the assumption that this wide cerebral autoregulation plateau could be applied on a within-individual basis is incorrect and greatly variable between individuals. Indeed, each data point on the autoreg...
2 CitationsSource