Pseudohypoxemia Secondary to Leukemia and Thrombocytosis

Accuracy and clinical performance of a continuous intra-arterial blood-gas monitoring system during thoracoscopic surgery

“…Comparison of the two methods was not the object of this study. Comparing PT7 and laboratory blood-gas analysis results is difficult because laboratory blood-gas analysis measurement is fraught with a variety of problems: samples for blood-gas analysis may easily be handled incorrectly by sample dilution, excess heparinized saline, 20 21 delays in analysis with the sample being stored at room temperature, 20 22 oxygen consumption from metabolism by leucocytes and other cells contained in the sample, 23 diffusion of gases through the plastic wall of syringes [24][25][26] and pressure of air bubbles in the samples, 22 26 27 particularly during transport. 28 In addition, the accuracy and variability of laboratory blood-gas analysers are applied in a recent evaluation of blood-gas analysers 29 : in the PO 2 range of 4-20 kPa and PCO 2 range of 2.7-10.6 kPa, respectively, 95% of measurements should be within Ϯ7.5% or Ϯ0.6 kPa of a reference; for PO 2 920 kPa and PCO 2 910.6 kPa, respectively, 95% of measurements should be within Ϯ12.5% of a reference; pH accuracy cannot be tested because there is no reference method.…”

Role of initial arterial blood gas variations in predicting the outcome of pneumonia patients with type I/II respiratory failure

“…Air bubbles were expressed and the syringe was capped and iced immediately. 9 The samples were analysed with blood gas analysers, which were calibrated according to the manufacturer's specifications and regular quality control measures were taken up, so as to minimise the measurement errors.…”

Platelet larceny: spurious hypoxaemia due to extreme thrombocytosis

“…Since then, several case reports [2][3][4][5][6] have described this phenomenon of leukocyte larceny in various types of leukaemia, based on the postulation that primitive leukaemic cells exhibit higher metabolic rates and cause larger drops in Pa,O 2 than do normal leukocytes [1,6].…”

“…Reticulocytes, platelets and leukocytes are among the constituents of blood that affect Pa,O 2 in shed blood, since oxygen consumption by mature erythrocytes and plasma is negligible, with leukocytes and platelets accounting for most of this phenomenon [1,6,8,9]. In 1911, ONAKA [10] was the first to demonstrate that respiration occurred in plasma after the erythrocytes and leukocytes had been spun down, and correctly attributed this oxygen consumption to blood platelets.…”

“…n 1979, HESS et al [1] showed that arterial oxygen tension (Pa,O 2 ) fell at a faster rate in patients with leukocytosis than in control subjects, and that this fall was great enough to result in an incorrect diagnosis of hypoxaemia. This artefactual phenomenon has been described primarily in association with oxygen consumption by the increased numbers of hypermetabolic leukocytes in various types of leukaemia [2][3][4][5] and has been termed leukocyte larceny [6].…”