Evaluation of sepsis using compensatory reserve measurement: A prospective clinical trial.

BACKGROUND: Sepsis, a leading cause of morbidity and mortality worldwide, characterized by metabolic and hemodynamic changes that can lead to multiorgan failure and death. The evaluation of a patient's condition is routinely performed by several objective criteria. The compensatory reserve measurement (CRM) represents a new paradigm that measures the total of all physiological compensatory mechanisms, using noninvasive photoplethysmography to read changes in arterial waveforms. The present study's aim was to evaluate the applicability and the predictive value of the CRM during sepsis. METHODS: Data were prospectively collected from patients hospitalized in the department of surgery because of different inflammatory illnesses. All subjects were evaluated with hemodynamic, laboratory measurements and CRM throughout hospitalization. RESULTS: Of 100 subjects enrolled, 84 patients were not septic. The remaining 16 patients were in sepsis (Sequential Organ Failure Assessment [SOFA] score, >2), 6 of whom were in septic shock and 4 died. When nonseptic patients were compared with septic patients, statistical differences were found in C-reactive protein level (p < 0.0005), SOFA score (p < 0.0005), and CRM (p < 0.0001). Other parameters did not show any difference between groups. The area under the receiver operating characteristic curve for CRM was 1, significantly higher than the area under the receiver operating characteristic for heart rate (0.78), systolic blood pressure (0.67), quick SOFA (0.81), and respiratory rate (0.56). CONCLUSION: Clinical criteria, imaging, and laboratory features used to identify a septic patient are suboptimal. This demonstrates the need for a monitoring device capable of detecting rapidly, constantly, and simply the sum condition of the ill patient. We have shown that CRM was able to distinguish between severe septic and nonseptic patients early in the course of hospitalization and was significantly more sensitive than the conventional diagnostic tools. Such capability to assess the septic patients or even to triage these patients will surely aid treatment of sepsis. LEVEL OF EVIDENCE: Care management, level II.

The effect of blood transfusion on compensatory reserve: A prospective clinical trial.

BACKGROUND: Bleeding activates the body's compensatory mechanisms, causing changes in vital signs to appear late in the course of progressive blood loss. These vital signs are maintained even when up to 30% to 40% of blood volume is lost. Laboratory tests such as hemoglobin, hematocrit, lactate, and base deficit levels do not change during acute phase of bleeding. The compensatory reserve measurement (CRM) represents a new paradigm that measures the total of all physiological compensatory mechanisms, using noninvasive photoplethysmography to read changes in arterial waveforms. This study compared CRM to traditional vital signs and laboratory tests in actively bleeding patients. METHODS: Study patients had gastrointestinal bleeding and required red blood cell (RBC) transfusion (n = 31). Control group patients had similar demographic and medical backgrounds. They were undergoing minor surgical procedures and not expected to receive RBC transfusion. Vital signs, mean arterial pressure, pulse pressure, hemoglobin and hematocrit levels, and CRM were recorded before and after RBC transfusion or the appropriate time interval for the control group. Receiver operator characteristic curves were plotted and areas under the curves (AUCs) were compared. RESULTS: CRM increased 10.5% after RBC transfusion, from 0.77 to 0.85 (p < 0.005). Hemoglobin level increased 22.4% after RBC transfusion from 7.3 to 8.7 (p < 0.005). Systolic and diastolic blood pressure, mean arterial pressure, pulse pressure, and heart rate did change significantly. The AUC for CRM as a single measurement for predicting hemorrhage at admission was 0.79, systolic blood pressure was 0.62, for heart rate was 0.60, and pulse pressure was 0.36. CONCLUSIONS: This study demonstrated that CRM is more sensitive to changes in blood volume than traditional vital signs are and could be used to monitor and assess resuscitation of actively bleeding patients. LEVEL OF EVIDENCE: Care management, level II.