En studie fra 1991 som beskriver hvordan hyperventillering og lav CO2 (hypokapni) påvirker perifere nervetråder og deres eksitabilitet. Sier at det er et lineært forhold mellom CO2 nedgang og perifere nervetråders eksitabilitet. Altså jo mindre CO2 som er tilstedet i blodet og vevet, jo lettere er det å oppleve smerter og muskelspenninger.
To define the nature of the disturbance created in peripheral nerve, the excitability of cutaneous and motor axons was monitored in 6 normal subjects requested to hyperventilate until paraesthesiae developed in the hands, face and trunk. This occurred when alveolar PCO2 (PACO2) had declined on average by 20 mmHg.
As PACO2 declined, the size of the compound sensory and muscle potentials evoked by a constant stimulus progressively increased, indicating an increase in axonal excitability. These changes occurred before paraesthesiae or tetany developed. In each subject there was a statistically significant inverse correlation between PACO2 and axonal excitability.
It is concluded that the paraesthesiae and tetany induced by hyperventilation result solely from changes in the excitability of cutaneous and motor axons in the peripheral nerve, presumably due to an alteration in the electrical properties of the axonal membrane resulting from a reduced plasma [Ca2+].