Continuous fiberoptic arterial and venous blood gas monitoring in hemorrhagic shock.
OBJECTIVE
To compare the performance of continuous fiberoptic blood gas monitoring with standard, intermittent blood gas sampling in the measurement of arterial and central venous blood gases during marked hemodynamic changes.


METHODS
Prospective, consecutive, enrollment, experimental study.


METHODS
Research laboratory at a university medical center.


METHODS
Seven anesthetized, mechanically ventilated pigs.


METHODS
Severe shock was induced by hemorrhage in pigs monitored by a pulmonary artery catheter, an arterial line, and two fiberoptic blood gas sensors: one intra-arterial, and the other inserted into the superior vena cava via right internal jugular vein cutdown. Fiberoptic blood gas monitor measurements were compared with standard intermittent blood gas sampling.


RESULTS
A total of 184 blood gas samples were compared in seven animals at baseline, during shock, and after resuscitation. The baseline mean (+/- 1 SD) cardiac output decreased from 4.0 +/- 0.9 to 1.2 +/- 0.6 L/min during shock and returned to baseline after retransfusion (3.9 +/- 1.3 L/min). The comparison of continuous fiberoptic blood gas monitoring with intermittent blood gas sampling showed a bias+/-precision of 0.035 +/- 0.047 for arterial pH, 0.021 +/- 0.031 for central venous pH, -4.09 +/- 2.96 mm Hg (-0.55 +/- 0.39 kPa) for arterial Pco2, -3.67 +/- 2.44 mm Hg (-0.49 +/- 0.3 3 kPa) for central venous Pco2, -5.79 +/- 9.64 mm Hg (-0.77 +/- 1.29 kPa) for arterial Po2, and -7.85 +/- 8.52 mm Hg (-1.05 +/- 1.14 kPa) for central venous Po2.


CONCLUSIONS
Continuous fiberoptic blood gas monitoring agrees closely with standard intermittent blood gas sampling during severe hemodynamic shifts and has a comparable accuracy for both arterial and venous blood gas measurements. Changes in venous Pco2 have recently been shown to correlate with changes in global tissue perfusion (eg, changes in cardiac output). Such data, available immediately via continuous venous blood gas monitoring, may be useful for monitoring shock and the response to resuscitation.
Oropello
J M
JM
Department of Surgery, Mount Sinai Medical Center, New York, USA.
Manasia
A
A
Hannon
E
E
Leibowitz
A
A
Benjamin
E
E
D000818:Animals; D015982:Bias; D001784:Blood Gas Analysis / Q000295:instrumentation; D001803:Blood Transfusion; D002245:Carbon Dioxide / Q000097:blood; D002302:Cardiac Output; D002406:Catheterization, Peripheral; D002407:Catheterization, Swan-Ganz; D005336:Fiber Optic Technology / Q000295:instrumentation; D006470:Hemorrhage / Q000097:blood; D007601:Jugular Veins; D008991:Monitoring, Physiologic / Q000295:instrumentation; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption; D010313:Partial Pressure; D011446:Prospective Studies; D012121:Respiration, Artificial; D012151:Resuscitation; D012771:Shock, Hemorrhagic / Q000097:blood* / Q000628:therapy; D013552:Swine; D014683:Vena Cava, Superior
D002245:Carbon Dioxide; D010100:Oxygen