Multi Frequency Phase Fluorimetry MFPF for Oxygen Partial Pressure Measurement: Ex Vivo Validation by Polarographic Clark-Type ElectrodeReportar como inadecuado




Multi Frequency Phase Fluorimetry MFPF for Oxygen Partial Pressure Measurement: Ex Vivo Validation by Polarographic Clark-Type Electrode - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Background

Measurement of partial pressure of oxygen PO2 at high temporal resolution remains a technological challenge. This study introduces a novel PO2 sensing technology based on Multi-Frequency Phase Fluorimetry MFPF. The aim was to validate MFPF against polarographic Clark-type electrode CTE PO2 measurements.

Methodology-Principal Findings

MFPF technology was first investigated in N = 8 anaesthetised pigs at FIO2 of 0.21, 0.4, 0.6, 0.8 and 1.0. At each FIO2 level, blood samples were withdrawn and PO2 was measured in vitro with MFPF using two FOXY-AL300 probes immediately followed by CTE measurement. Secondly, MFPF-PO2 readings were compared to CTE in an artificial circulatory setup human packed red blood cells, haematocrit of 30%. The impacts of temperature 20, 30, 40°C and blood flow 0.8, 1.6, 2.4, 3.2, 4.0 L min−1 on MFPF-PO2 measurements were assessed. MFPF response time in the gas- and blood-phase was determined. Porcine MFPF-PO2 ranged from 63 to 749 mmHg; the corresponding CTE samples from 43 to 712 mmHg. Linear regression: CTE = 15.59+1.18*MFPF R2 = 0.93; P<0.0001. Bland Altman analysis: meandiff 69.2 mmHg, rangediff -50.1-215.6 mmHg, 1.96-SD limits -56.3-194.8 mmHg. In artificial circulatory setup, MFPF-PO2 ranged from 20 to 567 mmHg and CTE samples from 11 to 575 mmHg. Linear regression: CTE = −8.73+1.05*MFPF R2 = 0.99; P<0.0001. Bland-Altman analysis: meandiff 6.6 mmHg, rangediff -9.7-20.5 mmHg, 1.96-SD limits -12.7-25.8 mmHg. Differences between MFPF and CTE-PO2 due to variations of temperature were less than 6 mmHg range 0–140 mmHg and less than 35 mmHg range 140–750 mmHg; differences due to variations in blood flow were less than 15 mmHg all P-values>0.05. MFPF response-time monoexponential was 1.48±0.26 s for the gas-phase and 1.51±0.20 s for the blood-phase.

Conclusions-Significance

MFPF-derived PO2 readings were reproducible and showed excellent correlation and good agreement with Clark-type electrode-based PO2 measurements. There was no relevant impact of temperature and blood flow upon MFPF-PO2 measurements. The response time of the MFPF FOXY-AL300 probe was adequate for real-time sensing in the blood phase.



Autor: Stefan Boehme , Bastian Duenges, Klaus U. Klein, Volker Hartwich, Beate Mayr, Jolanda Consiglio, James E. Baumgardner, Klaus Mark

Fuente: http://plos.srce.hr/



DESCARGAR PDF




Documentos relacionados