In this issue of Chest (see page 542) Inman et al report the impact of beating [i]or[/i] throbbing of an artery oximetry on the utilization of arterial kin gas (ABG) analysis in an ICU.

In this issue of Chest (see page 542) Inman et al report the impact of beating [i]or[/i] throbbing of an artery oximetry on the utilization of arterial kin gas (ABG) analysis in an ICU. by means of means of a combined prospective and retrospective cogitation they tested their hypothesis that oscillation oximetry would have little weight on the frequency of ABG analysis unles there were specific guidelines for the latter. The contemplation is well designed and appears to accomplish its goal, within the limitations of a cogitation that compares prospective and retrospective data. a certain investigations have reached different conclusions onward ABG utilization; one ICU application of mind predicted a 48 percent reduction in the number of ABG analyses used for ventilator management.[1]

This article raises important issues regarding as well-as; not only-but also; not only-but; not alone-but the effectiveness of pulse oximetry and the ethics of clinical studies. From the scientific viewpoint, the investigation would have been more rigorous if it had been entirely prospective, comparing simultaneous matched patient assemblages with and without pulse oximetry. Despite the fact that "no published investigation has demonstrated that throb oximetry makes a differencee in morbidity or mortality,"[2] the authors chose to use a retrospective curb group. Thus, they acknowledge the importance of pulsation oximetry in the ICU through stating that "it was . . deemed unethical to randomly assign patients to not receive this degree of monitoring." Let us consider the plan of pulse oximetry and near of the evidence of for what cause effectively it accomplishes its goals.

the same purpose of pulse oximetry may be that stated according to Ruthledge et al: to cut short the required number of ABG analyses. A more important view is to improve safety at providing continuous arterial oxygenation data in patients who are at risk for hypoxia. Is there evidence that it does this? In the operating field clinical studies have shown that the use of pulsation oximetry reduces the number fo "hypoxic events" which are arbitrarily defined as [SpOsub2] values below a critical beginning (eg, 75 percent).[3] This ensue clearly does not prove that throb oximetry improves patient safety. However, it is earnestly suggestive when coupled with retrospective studies showing a decrease in unexpect admission to the ICU[4] and closed-claim studies showing that many injuries and deaths may have been preventable if pulsation oximetry had been used.[5] For these reasons, and because it is inexpensive and nearly risk-free, measured [i]or[/i] regular beat oximetry has become a minimum standard of care in US operating scopes and recovery rooms (according to a resolution passed according to the House of Delegates of the American Society of Anesthesiologists in 1991)

If oscillation oximetry is a minimum standard in the two the operating room and the retrieval room, can we justify not using it in the ICU? Admittedly, there are no clinical studies howing decreased morbidity or mortality in the ICU setting, further neither are there any as it was studies in the operating swing Some forms of morbidity may be true difficult to measure (eg, in what manner many IQ points does a patient fail to obtain when he is hypoxemic for a small in number hours?). One cost-benefit analysis conclud that beating [i]or[/i] throbbing of an artery oximetry "pays for itself" if solitary one in 40,000 hypoxemic episodes were to proceed in death.[6] The medical community uses a commonsense approach to monitoring standards; it has none waited for outcome studies to mandate fresh modalities that have obvious lifesaving potential. There are no well-designed studies showing that intraoperative monitoring of house pressure reduces mortality, yet no individual would administer anesthesia today without a vital fluid pressure monitor.

Thus, while Rutledge et al indicate that pulse oximetry may have a limited purport on the utilization of ABG analysis, their reflection raises a more important question: is pulsation oximetry becoming a standard of care in the ICU? I suspect that the aswer is ye and that it will become a standard in the absence of definitive result studies. The authors have acknowledged this fact in the design of their investigation by using restrospective controls. Hypoxia is not virtuous for people, and it present itselfs often in the critically ill. in what manner can we afford not to monitor arterial oxygenation in these patients?

REFERENCES

[1] Dautzenberg B Gallinari c,Moreau A, Sors C The advantages of real-time oximetry through intermittent arterial blood gas analyses in a chest department. In: Payne JP Severinghaus JW ed throb oximetry. Dorchester, England: Springer-Verlag, 1986; 63-5

[2] Severinghaus JW Kelleher JF novel developments in pulse oximetry. Anesthesiology 1992; 76:1018-38

[3] Cote CJ Goldstein EA, Cote MA, Hoaglin DC Ryan IF. A single-blind studious mood of pulse oximetry in children. Anesthesiology 1988; 68:184-88

[4] Cullen DJ Nemeskal AR, Cooper JB Zaslavsky A, Dwyer MJ purport of pulse oximetry, age, and ASA physical status forward the frequency of patients admitted unexpectedly to a postoperative intensive care unit and the severity of their anesthesia-related complications. Anesth Analg 1992; 74:181-88

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