- Poster presentation
- Open Access
Contribution of red blood cells to the compensation for hypocapnic alkalosis through plasmatic strong ion difference variations
- Published: 1 March 2011
Keywords
- Public Health
- Chloride
- Blood Cell
- Graphical Representation
- Emergency Medicine
Introduction
Chloride shift is the movement of chloride between red blood cells (RBC) and plasma (and vice versa) caused by variations in pCO2. The aim of our study was to investigate changes in plasmatic strong ion difference (SID) during acute variations in pCO2 and their possible role in the compensation for hypocapnic alkalosis.
Methods
Patients admitted in this year to our ICU requiring extra-corporeal CO2 removal were enrolled. Couples of measurements of gases and electrolytes on blood entering (v) and leaving (a) the respiratory membrane were analyzed. SID was calculated as [Na+] + [K+] + 2[Ca2+] - [Cl-] - [Lac-]. Percentage variations in SID (SID%) were calculated as (SIDv - SIDa) × 100/SIDv. The same calculation was performed for pCO2 (pCO2%). Comparison between v and a values was performed by paired t test or the signed-rank test, as appropriate.
Results
* P < 0.05 versus first quartile. §P < 0.05 versus second. #P < 0.05 versus third. One-way ANOVA.
Conclusions
As a reduction in SID decreases pH, the observed movement of anions and cations probably limited the alkalinization caused by hypocapnia. In this model, the only source of electrolytes are blood cells (that is, no interstitium and no influence of the kidney is present); it is therefore conceivable to consider the observed phenomenon as the contribution of RBC for the compensation of acute hypocapnic alkalosis.
Authors’ Affiliations
Copyright
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.