Blood pressure measurement in patients with cardiogenic shock: the effect of norepinephrine Background: Before arterial cannulation for invasive blood pressure monitoring, clinical decision-making depends on non-invasive blood pressure in critically ill patients. Whether non-invasive blood pressure is comparable to invasive measurement is not clearly elucidated. We address this issue as it relates to the use of norepinephrine in patients with cardiogenic shock. Methods: We analysed invasive and non-invasive blood pressure in 85 patients admitted to the Coronary-Care Unit for cardiogenic shock. We compared initial blood pressure measurement (just after radial artery cannulation) and blood pressure taken during the first 72 hours after admission. Invasive blood pressure was used as the reference method. Results: Initial invasive mean and systolic arterial pressures were in a good agreement with oscillometric blood pressure; mean differences were −0.4 ± 8.8 and +6.1 ± 14.4 mmHg with correlation coefficients of 0.76 and 0.74. Doses of norepinephrine were significant negative determinants of invasive/oscillometric blood pressure differences. The invasive/oscillometric mean arterial pressures and SBP differences were +0.1 ± 3.4 and 7.6 ± 1.6 mmHg in patients treated with nothing or a maximum norepinephrine dose of 0.6 µg/kg/min. However, treatment with very high doses of norepinephrine was associated with a steep rise in mean arterial pressures and SBP invasive/oscillometric differences (−9.5 ± 3.3 and −8.5 ± 5.2 mmHg). In a total of 967 sets of blood pressure measurements, invasive/oscillometric differences were relatively stable across blood pressure categories, with the exception of measurements assessed after very high norepinephrine doses. Conclusions: Non-invasive BP is a sufficient substitute for invasive measurement in cardiogenic shock patients, with the exception of those receiving very high doses of norepinephrine.

Relation of short-term blood pressure variability to early renal effects in hypertensive patients with controlled blood pressure Introduction: Microalbuminuria is a common early hypertension-mediated organ damage, which correlates with the overall cardiovascular risk and development of end-stage renal damage. Lately, blood pressure variability has shown an additive value over traditional BP measurement in prediction of cardiovascular and renal involvement. Aim: Investigate the relation between short-term blood pressure variability and microalbuminuria in controlled hypertensive patients. Patients and methods: Ninety non-diabetic hypertensive patients with controlled blood pressure and normal estimated glomerular filtration rate had 24-hour ambulatory blood pressure monitoring with calculation of short-term blood pressure variability indices (SD, coefficient of variation and average reading variability of systolic and diastolic blood pressure for 24-hour, daytime and nighttime], and measurement of the albumin/creatinine ratio. Results: Patients were classified into group 1 (61 patients without microalbuminuria) and group 2 (29 patients with microalbuminuria). No significant difference was observed between both groups regarding age, sex, body mass index, office blood pressure, average 24-hour ambulatory blood pressure monitoring readings and dipping status, but significantly longer duration of hypertension in group 2. All blood pressure variability indices were significantly higher in group 2, which showed strong positive correlations with microalbuminuria level. Multivariate analysis represented an average reading variability of 24-hour systolic blood pressure as the most powerful independent predictor for microalbuminuria (r2 = 0.516, P = 0.001). Receiver operating characteristic curve analysis revealed that average reading variability of 24-hour systolic blood pressure (>12.55) could predict microalbuminuria (sensitivity = 89.7%, specificity = 88.5%, area under curve = 0.949, P = 0.001). Conclusion: Short-term blood pressure variability correlated well with early renal effects in controlled hypertensive patients. Average reading variability of 24-hour systolic blood pressure was the strongest predictor for microalbuminuria in such patients.

Arterial blood pressure correlates with 90-day mortality in sepsis patients: a retrospective multicenter derivation and validation study using high-frequency continuous data Objective To identify the outcome of patients with sepsis using high-frequency blood pressure data. Materials and methods This retrospective observational study was conducted at a university hospital ICU (derivation study) and at two urban hospitals (validation study) with data from adult sepsis patients who visited the centers during the same period. The area under the curve (AUC) of blood pressure falling below threshold was calculated. The predictive 90-day mortality (primary endpoint) area under threshold (AUT) and critical blood pressure were calculated as the maximum area under the curve of the receiver operating characteristic curve (AUCROC) and the threshold minus average AUT (derivation study), respectively. For the validation study, the derived 90-day mortality AUCROC (using critical blood pressure) was compared with Sequential Organ Failure Assessment (SOFA), Simplified Acute Physiology Score (SAPS) II, Acute Physiology and Chronic Health Evaluation (APACHE) II, and APACHE III. Results Derivation cohort (N = 137): the drop area from the mean blood pressure of 70 mmHg at 24–48 hours most accurately predicted 90-day mortality [critical blood pressure, 67.8 mmHg; AUCROC, 0.763; 95% confidence interval (CI), 0.653–0.890]. Validation cohort (N = 141): the 90-day mortality AUCROC (0.776) compared with the AUCROC for SOFA (0.711), SAPSII (0.771), APACHE II (0.745), and APACHE III (0.710) was not significantly different from the critical blood pressure 67.8 mmHg (P = 0.420). Conclusion High-frequency arterial blood pressure data of the period and extent of blood pressure depression can be useful in predicting the clinical outcomes of patients with sepsis.

Association between blood pressure components and the presence of carotid plaque among adults aged 45 years and older: a population-based cross-sectional study in rural China Objective: Pulse pressure is strongly associated with the early development of large-vessel atherosclerotic disease. However, the relationship between pulse pressure and carotid plaque in China is unknown. Thus, we investigated the associations of pulse pressure and mean arterial pressure with the presence of carotid plaques in a low-income population in rural China. Participants and methods: Residents, aged ≥45 years, without histories of stroke or cardiovascular disease were enrolled. Participant demographics, previous medical histories, and lifestyle information were collected; anthropometric measures, serum profiles, and B-mode ultrasonographic investigations were also performed. Results: The mean age of participants (n = 3789) was 59.9 years overall (men 61.1 years; women, 59.1 years). The mean SBP (146.42 mmHg) and DBP (86.81 mmHg), pulse pressures (59.61 mmHg), and mean arterial pressures (106.68 mmHg) were high in this population. The odds ratio (95% confidence interval) for the association of pulse pressure with the presence of carotid plaques was 1.028 (1.023–1.033), in the univariate analysis. After gradual adjustment for demographic features, risk factors, and serum profile measurements, this positive association remained statistically significant (all, P < 0.001). However, there was no significant relationship between mean arterial pressure and the presence of carotid plaques. Conclusion: These findings suggest that an elevated pulse pressure is an independent risk factor for the presence of carotid plaque. These results suggest that enhanced monitoring of blood pressure components, among low-income residents, is crucial for decreasing the risk of stroke and other cardiovascular disease in China.

Correlations between invasively measured aortic pressures and left ventricular end-diastolic pressure in patients undergoing coronary angiography Objective Data on ventricular-arterial coupling using invasive hemodynamic studies are limited. This study was performed to clarify the interaction between aortic pressures and left ventricular end-diastolic pressure (LVEDP) using invasive catheterization. Patients and methods A total of 104 consecutive stable patients (mean age, 65.8 ± 10.0 years; 56% men) undergoing invasive coronary angiography (ICA) were prospectively evaluated. LVEDP and central aortic pressures [systolic blood pressure (aSBP) and diastolic blood pressure (aDBP)] were sequentially measured using a pigtail catheter before ICA. Aortic pulse pressure (aPP) was defined by the difference between aSBP and aDBP. Results A total of 82 patients (79%) had obstructive coronary artery disease (≥50% stenosis). The mean LVEDP value was 18.7 ± 6.4 mmHg. Univariable analyses showed that aSBP (r = 0.309, P = 0.001) and aPP (r = 0.286, P = 0.003) significantly correlated with LVEDP, whereas aDBP was not correlated with LVEDP (P > 0.05). Multivariable analysis revealed that aSBP (β = 0.345, P = 0.001) and aPP (β = 0.276, P = 0.018) remained independent predictors of LVEDP even after controlling for potential confounders. Conclusion Invasively measured aSBP and aPP were independently associated with invasively measured LVEDP in patients undergoing ICA. This result provides additional evidence of a close interaction between central aortic pressure and LV diastolic function in this population.

Urinary catecholamines during stress and ambulatory blood pressure in children born full term but small for gestational age: a pilot study Objectives: Increased sympathetic activity is proposed to be a mechanism of high blood pressure in children born small for gestational age. Ambulatory blood pressure monitoring is a form of blood pressure measurement that can detect high blood pressure outside the hospital in patients with normal office blood pressure. This condition is called masked hypertension. There are limited data on association between ambulatory blood pressure and urinary catecholamines during exposure to stress in children born small for gestational age. Methods: Nineteen children born small for gestational age and 17 healthy controls ages 6–14 years old were included. Demographic data and office blood pressure were collected. Urinary catecholamines were collected before and after exposure to stress including mathematical test and venipuncture. Afterwards, ambulatory blood pressure monitoring was performed to obtain 24-hour blood pressure profiles. Results: All children had normal office blood pressure but ambulatory blood pressure monitoring revealed masked hypertension in six children born small for gestational age (32%) and two controls (11.7%). After stress, median percentage of increase in urine norepinephrine levels was greater in children born small for gestational age with masked hypertension than that of children born small for gestational age without masked hypertension (9.2 vs. −13.2 μg/g creatinine, P = 0.05). There was no increase in urine norepinephrine levels in controls with masked hypertension. Among children born small for gestational age, awake SBP z-scores had significant positive correlations with pre- and post-stress urinary dopamine levels (r = 0.530, P = 0.02 and r = 0.597, P = 0.007, respectively). Conclusion: Masked hypertension is not uncommon in children born small for gestational age. After stress, urinary norepinephrine levels were increased in children born small for gestational age with masked hypertension.

Effects of doxazosin mesylate versus nifedipine on blood pressure variability in hypertensive patients: a randomized crossover study (SIMILAR) Objective Blood pressure variability (BPV) is a powerful predictor of end-organ damage, cardiovascular events and mortality independently of the BP level. Calcium channel blockers may offer an advantage over other first-line antihypertensive drugs by preventing increased BPV. But the effect of alpha-receptor blockers on BPV in hypertensive patients is still unclear. Methods In this crossover trial, 36 hypertensive patients were randomly assigned to two groups, receiving doxazosin mesylate gastrointestinal therapeutic system (GITS) (4 mg/day) or nifedipine GITS (30 mg/day) for 12 weeks, followed by a 2-week washout period then a 12-week crossover phase. At baseline and after 12-week treatment, 24-hour ambulatory BP monitoring was performed. BPV was evaluated through standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of systolic BP (SBP) and diastolic BP (DBP) during daytime, nighttime and over 24 hours. Results After 12-week treatment, both doxazosin and nifedipine significantly decreased SBP and DBP (P < 0.05), whereas no between-group differences were shown (P>0.05). Systolic BPV (24-hour SD, CV, and ARV; daytime SD; nighttime SD and CV) and diastolic BPV (24-hour SD and ARV) were significantly lowered by nifedipine (P < 0.05); doxazosin resulted in significant reductions of systolic BPV (24-hour SD, CV and ARV; daytime SD; nighttime SD) and diastolic BPV (nighttime SD and CV) (P < 0.05). Doxazosin was revealed to be as effective as nifedipine for reducing BPV (P > 0.05) except for 24-hour SBP ARV. Conclusions Doxazosin mesylate GITS had similar therapeutic effects on BP, BP SD, and BP CV lowering as nifedipine GITS in patients with mild-to-moderate essential hypertension.

Interarm blood pressure measurement and the reference-arm assignment variability Objective The arm with the higher blood pressure (BP) is assigned as the follow up arm for hypertensive patients (reference-arm). We evaluated the reproducibility of this assignment. Methods BP was measured simultaneously on both arms with a double cuff validated device in two visits separated <10 days (two sets of three readings per visit). Two reference-arms were assigned in each visit (the arm with higher BP, at least ≥1 mmHg). The intravisit and intervisit agreements of this assignment were evaluated. Results We included 313 hypertensive patients. First visit mean right arm BP was 131.6 (16.6)/75.3 (9.4) mmHg and left arm BP was 132.4 (16.9)/75.7 (9.7) mmHg (P = 0.002). Intravisit concordance at the first and second visits were κ = 0.60 [95% confidence interval (CI), 0.516–0.696] and κ = 0.45 [95% CI, 0.356–0.555], respectively. Therefore, 21.8% of patients (at the first visit) and 29.1% (at the second visit) with the right arm as the reference-arm in the first round of readings changed to the left arm in the same visit in the second round of readings. The intervisit κ index was 0.25 [95% CI, 0.147–0.365]. After that, 36.8% of patients with the right arm as the reference-arm at the first visit changed to the left arm at the second visit. The subgroup (9.5%) with an interarm systolic BP difference ≥10 mmHg at the first visit did not differ significantly from the rest of patients. Conclusion The reference-arm assignment agreement is weak to moderate. The assignment of the reference-arm should be individualized and not considered as definitive.