The form factor (FF) is a pulse shape indicator that corresponds to the fraction of pulse pressure added to diastolic blood pressure to estimate the time-averaged mean arterial pressure (MAP). Our ...invasive study assessed the FF value and variability at the radial and femoral artery levels and evaluated the recommended fixed FF value of 0.33.
Hemodynamically stable patients were prospectively included in 2 intensive care units. FF was documented at baseline and during dynamic maneuvers. A total of 632 patients (64±16 years of age, 66% men, MAP=81±14 mm Hg) were included. Among them, 355 (56%) had a radial catheter and 277 (44%) had a femoral catheter. The FF was 0.34±0.06. In multiple linear regression, FF was influenced by biological sex (
<0.0001) and heart rate (
=0.04) but not by height, weight, or catheter location. The radial FF was 0.35±0.06, whereas the femoral FF was 0.34±0.05 (
=0.08). Both radial and femoral FF were higher in women than in men (
<0.05). When using the 0.33 FF value to estimate MAP, the error was -0.4±4.0 mm Hg and -0.1±2.9 mm Hg at the radial and femoral level, respectively, and the MAP estimate still demonstrated high accuracy and good precision even after changes in norepinephrine dose, increase in positive end-expiratory pressure level, fluid administration, or prone positioning (n=218).
Despite higher FF in women and despite interindividual variability in FF, using a fixed FF value of 0.33 yielded accurate and precise estimations of MAP. This finding has potential implications for blood pressure monitoring devices and the study of pulse wave amplification.
The neutrophil to lymphocyte ratio (NLR) and the platelet to lymphocyte ratio (PLR) have been identified as predictive factors in several cardiovascular diseases but their significance in patients ...with internal carotid artery (ICA) stenosis is still poorly known. The aim of this study was to determine the clinical significance of the preoperative NLR and PLR in patients with ICA stenosis undergoing carotid endarterectomy.
Consecutive patients who underwent carotid endarterectomy for ICA stenosis were retrospectively included (n = 270). The population was divided into 2 series of 4 groups based on the quartile values of the preoperative NLR and PLR: group Ia (NLR < 1.5), IIa (1.50 < NLR < 2.07), IIIa (2.07 < NLR < 2.95), IVa (NLR>2.95), and group Ib (PLR < 86.6), IIb (86.6 < PLR < 111.7), IIIb (111.7 < PLR < 148.3), IVb (PLR > 148.3). Clinical characteristics and 30-day postoperative outcomes were compared among the groups.
One death (.4%) was reported during the 30-day postoperative period and the overall stroke and death rate was 1.5%. The proportion of patients with symptomatic ICA stenosis were significantly higher in group IVa compared to groups Ia, IIa, IIIa (64.2% vs 33.8%, 44.8% and 45.6%, respectively, P = .005), and higher in group IVb compared to groups Ib, IIb, IIIb (59.7% vs 47.1%, 35.8%, 45.6%, P = .051). No significant difference on 30-day postoperative all-cause complications was observed among the groups.
A high preoperative NLR and PLR is significantly associated with symptomatic ICA stenosis. Further studies are required to determine their interest as predictors of postoperative outcomes in patients undergoing carotid endarterectomy.
Introduction:
The predictive value of the platelet to lymphocyte ratio (PLR) has been demonstrated in several cardiovascular diseases. The aim of this study was to investigate the interest of the ...preoperative PLR as a predictor of 30-day postoperative outcome in patients with abdominal aortic aneurysm (AAA) undergoing open or endovascular surgical repair.
Material and Methods:
Two hundred twenty-four consecutive patients with infrarenal AAA were retrospectively included and divided into 4 quartiles according to the value of the preoperative PLR: PLR < 91.5 (group I), 91.5 < PLR < 120.8 (group II), 120.8 < PLR < 163.3 (group III), and PLR > 163.3 (group IV).
Results:
The AAA diameter was similar among the groups (54.9 mm vs 58.6, 57.5, and 58.7 mm; P = .4655). The proportion of symptomatic AAA and the procedural characteristics did not differ. Patients from group I and IV had significantly higher rates of all-cause postoperative complications compared to group II and III (55.4% and 64.3% vs 39.3% and 46.4%, respectively; P = .0478). The all-cause mortality tended to be higher in group I and IV (7.1% and 8.9% vs 0% and 3.6%, respectively; P = .1305).
Conclusion:
Extreme values of PLR are associated with a higher risk of complications following AAA surgical repair, suggesting its interest as a biomarker to evaluate the surgical risk.