اکسیژناسیون بافت بیماران بعد از عمل: یک مطالعه مقدماتی

Abstract Aims: In the absence of a gold standard for the clinical diagnosis of shock, clinicians traditionally rely on measurements of vital signs, arterial oxygen saturation of hemoglobin (SaO2), serum lactate, and arterial base deficit. Yet values derived from these measurements may remain relatively normal during the early stages of shock while the patient’s condition is indeed deteriorating, and the evolution from mild to severe shock can be subtle or extremely rapid. Tissue oxygen saturation (StO2) monitoring is a noninvasive technology that has been reported to function as an early warning sign of tissue hypoxia, as systemic blood flow is redistributed to critical organs, primarily in patients with hemorrhagic and traumatic shock, but also in patients with septic shock and in those undergoing cardiac surgery. This pilot study examined the strength of the relationship between initial postoperative StO2 values and the development of complications in adult patients. Methods: This observational, prospective study was carried out in a convenience sample of 31 hemodynamically stable, postoperative adults admitted to the Post-Anesthesia Care Unit (PACU) and Cardiothoracic Care Intensive Care Unit (CTICU) at a 643-bed Level I trauma medical center in the Northeastern region of the United States during 2012. Institutional Review Board approval was obtained from the university and the medical center. Patients were approached in the preoperative holding area, the study was explained, and patients were shown the equipment that would be used in the study. After the patient had been admitted to either the PACU or CTICU, the investigators waited until the bedside nurse performed an initial assessment of hemodynamic stability. Following calibration of the InSpectra monitor, the StO2 probe was placed adhesively on the thenar eminence of the patient’s hand. The StO2 data was monitored continuously, downloaded to a laptop computer, and recorded manually every 15 minutes for at least 2 hours. Results: The first, last, and average StO2 values were, respectively: 80.71%+9.16 80.94%+7.07 and, 80.56% +7.18. However, the mean minimum values of the first, last, and average StO2 values were, respectively: 55%, 67%, and 65%. When minimum StO2 values were tested for differences in the incidence of postoperative complications, there was a significant difference (x=76.9+7.44, range 59-92 Chi Sq, df 18, p=0.020). Conclusions: While postoperative patients maintained a stable level of StO2 values during their early recovery, a case report illustrates that sudden drops in StO2 values may be sensitive to the detection of the potential for complications.

اکسیژناسیون بافت بیماران بعد از عمل: یک مطالعه مقدماتی Keywords:

Spectroscopy , Near-Infrared , Tissue oxygen saturation