Level of agreement of point-of-care and laboratory HbA1c measurements in the preoperative outpatient clinic in non-diabetic patients who are overweight or obese.

Implementation of point-of-care HbA1c devices in the preoperative outpatient clinic might facilitate the early diagnosis of glycemic disturbances in overweight or obese patients undergoing surgery, but validation studies in this setting do not exist. We determined the level of agreement between a point-of-care and laboratory HbA1c test in non-diabetic patients visiting the outpatient clinic for preoperative risk profiling. Point-of-care HbA1c levels were measured in whole blood obtained by a finger prick (Siemens DCA Vantage HbA1c analyzer) and in hemolysed EDTA blood in the central laboratory (LAB). Bland Altman and Clarke's error grid analysis were used to analyze the agreement between the point-of-care and laboratory measurements. Patients (n = 49) were 55 ± 11 years old, 47% were male with a body mass index (BMI) of 30.6 ± 3.4 kg/m2. The mean HbA1c was 38.1 ± 3.7 mmol/mol or 5.6 ± 0.3%. One patient was diagnosed with a HbA1c indicative for diabetes mellitus (6.7%). Bland Altman analysis revealed a bias of - 0.53 ± 1.81 mmol/mol with limits of agreement of - 4.09 to 3.03 mmol/mol and a bias of - 0.05 ± 0.17% with limits of agreement - 0.39 to 0.28%. The percentage error was 9.2% and 5.9% for HbA1c expressed in mmol/mol and %, respectively. Clarke's error grid analysis showed that 48 out of 49 measurements were located in area A (98%). Point-of-care HbA1c measurements showed a high level of agreement with the laboratory test in the outpatient setting, and may be used for preoperative risk profiling in patients prone to cardiometabolic complications.Trial registration: Netherlands Trial Register NTR3057.

Agreement between ccNexfin CO-trek cardiac output and intermittent cold-bolus pulmonary thermodilution in a prospective multicenter study.

BACKGROUND: The ccNexfin System uses the CO-trek algorithm to analyze a non-invasively obtained arterial pressure waveform and calculate cardiac output (NEXCO). It remains matter of debate whether NEXCO can replace invasive, pulmonary artery catheter-derived, cold-bolus pulmonary thermodilution cardiac output measurement (PACCO). This study aimed at testing NEXCO-PACCO agreement in a large sample size, multicenter study. We hypothesized that agreement between NEXCO and PACCO would be demonstrated by a mean accuracy (bias) <0.6 L/min with a percentage error <30%. METHODS: Patients undergoing cardiac surgery in three academic hospitals clinically requiring pulmonary artery catheterization were included. Exclusion criteria were aortic, pulmonary and tricuspid (valve) abnormalities, non-sinus rhythm and insufficient perfusion of the digits such as in Raynaud's disease. After induction of anesthesia, cardiac output was measured with four cold bolus thermodilution measurements and four averaged 30-second ccNexfin measurements randomized through the respiratory cycle to obtain one measurement pair. Mean accuracy and precision of ccNexfin were expressed as bias (mean of all NEXCO-PACCO differences) and limits of agreement (LOA) (1.96·SD of bias). Percentage error was calculated as [LOA / (NEXCO-PACCO average)]. RESULTS: Fifty-five patients were enrolled in the study, 51 completed the protocol. Median PACCO was 3.7 (IQR: 3.2 to 4.6) L/min and median NEXCO was 3.8 (IQR: 3.1 to 4.7) L/min. NEXCO-PACCO bias was 0.1 (LOA: -1.4 to +1.6) L/min with a 37% percentage error. CONCLUSIONS: In this study, cardiac output measurement with ccNexfin failed to meet the predefined criteria for agreement with cold-bolus pulmonary artery thermodilution.