Monitoring arterial oxygen

Respiratory System Spontaneous respiration is rapid and shallow during halothane anesthesia. The decreased alveolar ventilation results in an elevation in arterial CO tension from 40 mm Hg to >50 mm Hg at 1 MAC. The elevated CO does not provoke a compensatory increase in ventilation, because halothane causes a concentration-dependent inhibition of the ventilatory response to COj. Halothane also inhibits peripheral chemoceptor responses to arterial hypoxemia. Thus, neither hemodynamic (tachycardia and hypertension) nor ventilatory responses to hypoxemia are observed during halothane anesthesia, making it prudent to monitor arterial oxygenation directly. 

Maintain an open ainAray and assist ventilation if necessary (see pp 1-7). Administer supplemental oxygen, and monitor arterial blood gases and chest x-rays. 

Yoshiya I., Shimada Y., and Tanaka K. 1980. Spectrophotometric monitoring of arterial oxygen saturation in the fingertip. Med. Biol. Eng. Comput. 18 27. 

Treatment for the respiratory damage involves oxygen supplements, intubation, and artificial ventilation when indicated, as well as the use of a hyperbaric chamber to remove carbon monoxide, if needed. Any restriction to the chest owing to burned skin is removed surgically. The nurse must monitor arterial blood gases and oxygen saturation levels to determine the effectiveness of treatment. In addition, the nurse should monitor for signs of acidosis and related acid-base imbalances. <3 ... 

In the emergency room, continue giving oxygen. Monitor arterial blood gas. Evaluate for pulmonary involvement. Observe for liver or kidney damage. 

Very frequently used in analytical laboratories, GSE have been introduced into clinical laboratories in the last few years for the direct determination of blood gases on very small samples[31] and for intravascular monitoring of oxygen, tension of blood[32,34]. Non-invasive transcutaneous oxygen or carbon dioxide electrodes may alternatively be placed on the surface of the heated skin of neonates or adults the electrode response is directly proportional to arterial oxygen and carbon dioxide tensions[34-38]. 

Senn O, Clarenbach CF, Kaplan V, et al. Monitoring Carbon Dioxide Tension and arterial oxygen saturation by a single earlobe sensor in patients with critical illness or sleep apnea. Chest 2005 128 1291-1296. 

The use of oxygen in pediatric incubators is an important factor in increasing the survival rate of premature infants who develop cyanosis. However, the use of oxygen is associated with risk of developing the visual defect known as retrolental fibroplasia (38). A careflil monitoring of arterial blood oxygen partial pressure is important. 

Many different types of sensory receptors are located throughout the body. These receptors monitor the status of the internal environment or that of the surroundings. Sensory receptors are sensitive to specific types of stimuli and measure the value of a physiological variable. For example, arterial baroreceptors measure blood pressure and chemoreceptors measure the oxygen and carbon dioxide content of the blood. The information detected by these sensors then travels by way of afferent neuronal pathways to the central nervous system (CNS). The CNS is the integrative portion of the nervous system and consists of the (1) brain and the (2) spinal cord. 

In acute exacerbations of COPD, white blood cell count, vital signs, chest x-ray, and changes in frequency of dyspnea, sputum volume, and sputum purulence should be assessed at the onset and throughout the exacerbation. In more severe exacerbations, arterial blood gases and oxygen saturation should also be monitored. 

With arsine exposure, there may be potential severe hemolysis (the breakdown of red blood cells and the release of hemoglobin). Ensure adequate oxygenation by arterial blood measurement or pulse oxygenation monitoring. Use diuretics to maintain urinary flow. 

Figure 9.15. In vivo partial pressure of oxygen in arterial blood of dogs over the period of 10 h. The solid lines represent the analyses monitor by the instrument. Two different polymer solutions are shown. The dots represent the batch gas analysis measured with a Nova Biomedical blood gas analyzer. (From Ref. 21 with permission.)...

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