Use of glass capillaries avoids the time changes in high blood PO(2) observed with plastic syringes.
OBJECTIVE
In adults, arterial blood samples are usually drawn using plastic syringes. In contrast to glass syringes, plastic syringes let oxygen diffuse through their wall. This results in PO(2) changes during storage, especially when PO(2) is high. An alternative to glass syringes is the Microsampler (Roche Diagnostics; Schaffhausen, Switzerland), a commercially available device consisting of a heparinized glass capillary fitted with a 26-gauge needle and used to collect arterial blood in the same way as a plastic syringe fitted with a needle.


METHODS
We evaluated the performance of the Roche Microsampler for storing arterial blood in view of PO(2) measurement, comparatively with glass and plastic syringes. Five approximate initial PO(2) levels (650, 400, 200, 130, and 80 mm Hg) and two storage temperatures (ambient temperature and 4 degrees C) were studied.


METHODS
Bench study.


RESULTS
Plastic syringes allowed reliable measurement of PO(2) values when initial PO(2) was too low to ensure complete hemoglobin oxygen saturation, but were associated with time-dependent underestimation of PO(2) at higher initial PO(2) values. No such underestimation occurred with the Roche Microsampler stored at 4 degrees C for up to 1 h for all PO(2) levels studied.


CONCLUSIONS
The Roche Microsamplers appeared to be reliable devices in preventing oxygen diffusion.
d'Ortho
M P
MP
Service de Physiologie-Explorations Fonctionnelles and Institut National de la Santé et de la Recherche Médicale, INSERM U492, Hôpital Henri Mondor, Hôpitaux de Paris, Créteil, France.
Delclaux
C
C
Zerah
F
F
Herigault
R
R
Adnot
S
S
Harf
A
A
D001800:Blood Specimen Collection / Q000295:instrumentation* / Q000379:methods; D004058:Diffusion; D005898:Glass; D006801:Humans; D010100:Oxygen / Q000097:blood*; D010969:Plastics; D013594:Syringes; D013696:Temperature; D013997:Time Factors
D010969:Plastics; D010100:Oxygen