Arterial Pressure Monitoring Research Articles

(846) Remote Pulmonary Artery Pressure Monitoring in a Patient with Severe Pulmonary Arterial Hypertension - Is It Underutilized?

(846) Remote Pulmonary Artery Pressure Monitoring in a Patient with Severe Pulmonary Arterial Hypertension - Is It Underutilized?

Daily profile of arterial and central aortic pressure in patients with arterial hypertension and non-alcoholic fatty liver disease

Оbjective : to evaluate the features of daily monitoring of arterial and central aortic pressure in patients with arterial hypertension and non-alcoholic fatty liver disease. Materials and methods: a comparative cross-sectional study was conducted, which involved 120 patients (continuous sample, unorganized population), aged 45 to 65 years (mean age 56.2±8.8 years), including men (34 (28.3%) with AH stage I–II, 1–2 degree. The main group included 60 patients with hypertension and NAFLD, the control group included 60 patients with isolated hypertension. When examining patients, a clinical examination was carried out: taking an anamnesis, measuring "office" blood pressure, anthropometric parameters, calculating body mass index (BMI), WC. 24-hour monitoring of arterial (ABPM) and central aortic pressure (CAP) was assessed using the BPLab complex and Vasotens 24 software (LLC Petr Telegin, Russia). The SCORE scale was used to calculate total cardiovascular risk and 10-year fatal risk. Results : all patients of the study groups underwent ABPM. It was proved that in the patients of the main group, the IV SBP and IV DBP during the day and night significantly exceeded the similar parameters of patients in the comparison group (IV SBP: p=0.0019, p=0.007; IV DBP: p=0.009, p=0.009, respectively). One of the important criteria for assessing blood pressure was the determination of the degree of nighttime decrease in SBP and DBP — the daily index (SI), characterizing the balance in the work of the sympathetic and parasympathetic parts of the autonomic nervous system. In the main group, compared with the control group, there were more patients with SI DBP in the range from 0.0% to 10.0% (non-dipper) (p=0.034), with an increase in SBP at night (night-picker) (p=0.031). When assessing the parameters of CAP, in patients with AH and NAFLD, statistically significantly higher values of mean daily systolic (SADAo) and diastolic (DADo) aortic pressure were observed (p=0.016, p=0.039, respectively), SBP in the daytime (p=0.027), SADao and DADAO at night (p=0.002, p=0.003, respectively), compared with patients with isolated hypertension. Calculation of the risk of cardiovascular complications, in patients with hypertension and NAFLD, a significant increase in the 10-year risk of cardiovascular events was determined, compared with patients with isolated hypertension (3.7 (1.6; 6.0) vs 2.0 (0.6 ;4.3) %, p=0.013). Conclusion : according to the results of 24-hour BP monitoring, in patients with AH and NAFLD, compared with patients with isolated AH, a more significant increase in mean SBP and DBP, an increase in the rate of morning rise and BP variability, and the hypertension time index were revealed. In the main group, patients with a nocturnal increase in SBP were detected significantly more often, which indicates a greater risk of cardiovascular complications in patients with hypertension and NAFLD. In addition, compared with patients with isolated AH, patients with AH and NAFLD showed more significant increases in average daily and nighttime SBPao and DADAO.

Feasibility and Accuracy of Noninvasive Continuous Arterial Pressure Monitoring during Transcatheter Atrial Fibrillation Ablation

Transcatheter atrial fibrillation (AF) ablation is still carried out with continuous invasive radial arterial blood pressure (IBP) monitoring in many centers. Continuous noninvasive blood pressure (CNBP) measurement using the volume-clamp method is a noninvasive alternative method used in ICU. No data on CNBP reliability are available in the electrophysiology lab during AF ablation, where rhythm variations are common. The objective of the present study was to compare continuous noninvasive arterial pressure measured with the ClearSight device (Edwards Lifesciences, Irvine, CA, USA) with invasive radial artery pressure used as the reference method during AF ablation. We prospectively enrolled 55 consecutive patients (age 62 ± 11 years, 80% male) undergoing transcatheter AF ablation (62% paroxysmal, 38% persistent) at our center. Standard of care IBP monitoring via a radial cannula and a contralateral noninvasive finger volume-clamp CNBP measurement device were positioned simultaneously in all patients for the entire procedure. Bland-Altman analysis was used to analyze the agreement between the two techniques. A total of 1219 paired measurements for systolic, diastolic, and mean arterial pressure were obtained in 55 subjects, with a mean (SD) of 22 (9) measurements per patient. The mean bias (SD) was -12.97 (13.89) mmHg for systolic pressure (level of agreement -14.24-40.20; correlation coefficient 0.84), -1.85 (8.52) mmHg for diastolic pressure (level of agreement -18.54-14.84; correlation coefficient 0.77) and 2.31 (8.75) mmHg for mean pressure (level of agreement -14.84-19.46; correlation coefficient 0.85). In patients undergoing AF ablation, CNBP monitoring with the ClearSight device showed acceptable agreement with IBP monitoring. Larger studies are needed to confirm the potential clinical implications of continuous noninvasive BP monitoring during AF ablation.

Cuff size, cuff placement, blood pressure state, and monitoring technique can influence indirect arterial blood pressure monitoring in anesthetized bats (Pteropus vampyrus)

Evaluate agreement between 2 non-invasive blood pressure (NIBP) techniques and invasive arterial blood pressure (IBP) in anesthetized bats using various cuff sizes and cuff positioning while also evaluating its performance during hypertension and hypotension. 8 bats (1.1 ± 0.2 kg). Bats were anesthetized with isoflurane in oxygen. NIBP was measured using oscillometric (NIBP-O) and Doppler (NIBP-D) techniques in the pectoral limb (PEC) and pelvic limbs (PEL) using 3 cuff sizes (1, 2, and 3). NIBP measurements were compared with IBP; systolic (SAPinvasive), mean (MAPinvasive), and diastolic arterial blood pressure (DAPinvasive) during normotension, hypertension, and hypotension. Hypotension was induced with isoflurane (3.8 ± 1.2%) and hypertension with norepinephrine (3 ± 0.5 µg/kg/min). Data analysis included Bland-Altman analyses and 3-way ANOVA. Results were reported as mean bias (95% CI). NIBP-O monitor reported 29% errors, and experienced more failures with hypertension, cuff placement on PEC, and using a size 1 cuff. Across states, an agreement between NIBP-D and MAPinvasive with cuff 2 on PEL (-3 mmHg [-8, 1]), and NIBP-D and SAPinvasive with cuff 3 on PEC (2 mmHg [-5, 9 mmHg]) was achieved. NIBP-D over-estimated SAPinvasive and MAPinvasive during hypertension in both limbs with cuffs 1 and 2. Except during hypotension, NIBP-O underestimated MAPinvasive and DAPinvasive using a size 2 cuff on PEL. In anesthetized bats, NIBP-O is unreliable for estimating IBP. NIBP-D shows acceptable agreement with MAPinvasive with cuff size 2 on PEL, and with SAPinvasive with cuff size 3 on PEC across a wide range of IBP values.

Critical Closing Pressure and Cerebrovascular Resistance Responses to Intracranial Pressure Variations in Neurocritical Patients

BackgroundCritical closing pressure (CrCP) and resistance-area product (RAP) have been conceived as compasses to optimize cerebral perfusion pressure (CPP) and monitor cerebrovascular resistance, respectively. However, for patients with acute brain injury (ABI), the impact of intracranial pressure (ICP) variability on these variables is poorly understood. The present study evaluates the effects of a controlled ICP variation on CrCP and RAP among patients with ABI.MethodsConsecutive neurocritical patients with ICP monitoring were included along with transcranial Doppler and invasive arterial blood pressure monitoring. Internal jugular veins compression was performed for 60 s for the elevation of intracranial blood volume and ICP. Patients were separated in groups according to previous intracranial hypertension severity, with either no skull opening (Sk1), neurosurgical mass lesions evacuation, or decompressive craniectomy (DC) (patients with DC [Sk3]).ResultsAmong 98 included patients, the correlation between change (Δ) in ICP and the corresponding ΔCrCP was strong (group Sk1 r = 0.643 [p = 0.0007], group with neurosurgical mass lesions evacuation r = 0.732 [p < 0.0001], and group Sk3 r = 0.580 [p = 0.003], respectively). Patients from group Sk3 presented a significantly higher ΔRAP (p = 0.005); however, for this group, a higher response in mean arterial pressure (change in mean arterial pressure p = 0.034) was observed. Exclusively, group Sk1 disclosed reduction in ICP before internal jugular veins compression withholding.ConclusionsThis study elucidates that CrCP reliably changes in accordance with ICP, being useful to indicate ideal CPP in neurocritical settings. In the early days after DC, cerebrovascular resistance seems to remain elevated, despite exacerbated arterial blood pressure responses in efforts to maintain CPP stable. Patients with ABI with no need of surgical procedures appear to remain with more effective ICP compensatory mechanisms when compared with those who underwent neurosurgical interventions.

Enhanced external counterpulsation improves dysfunction of forearm muscle caused by radial artery occlusion.

This study aimed to investigate the therapeutic effect of enhanced external counterpulsation (EECP) on radial artery occlusion (RAO) through the oscillatory shear (OS) and pulsatile shear (PS) models of human umbilical vein endothelial cells (HUVECs) and RAO dog models. We used high-throughput sequencing data GSE92506 in GEO database to conduct time-series analysis of functional molecules on OS intervened HUVECs, and then compared the different molecules and their functions between PS and OS. Additionally, we studied the effect of EECP on the radial artery hemodynamics in Labrador dogs through multi-channel physiological monitor. Finally, we studied the therapeutic effect of EECP on RAO at the histological level through Hematoxylin-Eosin staining, Masson staining, ATPase staining and immunofluorescence in nine Labrador dogs. With the extension of OS intervention, the cell cycle decreased, blood vessel endothelial cell proliferation and angiogenesis responses of HUVECs were down-regulated. By contrast, the inflammation and oxidative stress responses and the related pathways of anaerobic metabolism of HUVECs were up-regulated. Additionally, we found that compared with OS, PS can significantly up-regulate muscle synthesis, angiogenesis, and NO production related molecules. Meanwhile, PS can significantly down-regulate inflammation and oxidative stress related molecules. The invasive arterial pressure monitoring showed that 30Kpa EECP treatment could significantly increase the radial artery peak pressure (p = 0.030, 95%CI, 7.236-82.524). Masson staining showed that RAO significantly increased muscle interstitial fibrosis (p = 0.002, 95%CI, 0.748-2.128), and EECP treatment can reduce this change (p = 0.011, 95%CI, -1.676 to -0.296). ATPase staining showed that RAO significantly increased the area of type II muscle fibers (p = 0.004, 95%CI, 7.181-25.326), and EECP treatment could reduce this change (p = 0.001, 95%CI, -29.213 to -11.069). In addition, immunofluorescence showed that EECP increased angiogenesis in muscle tissue (p = 0.035, 95%CI, 0.024-0.528). EECP improves interstitial fibrosis and hypoxia, and increases angiogenesis of muscle tissue around radial artery induced by RAO.

Impact of exercise on pulmonary artery pressure in patients with heart failure using an ambulatory pulmonary artery pressure monitor

In this multicenter prospective study, we explored the relationship between pulmonary artery pressure (PAP) at rest and in response to a 6-min walk test (6MWT) in ambulatory patients with heart failure (HF) with an implantable PAP sensor (CardioMEMS, Abbott). Between 5/2019 and 2/2021, HF patients with a CardioMEMS sensor were recruited from seven sites. PAP was recorded in the supine and seated position at rest and in the seated position immediately post-exercise. In our cohort of 66 patients, mean age was 70 ± 12 years, 67% male, left ventricular ejection fraction (LVEF) < 50% in 53%, mean 6MWT distance was 277 ± 95 meters. Resting seated PAPs were 31 ± 15 mmHg (systolic), 13 ± 8 mmHg (diastolic), and 20 ± 11 mmHg (mean). The pressures were lower in the seated rather than the supine position. After 6MWT, the pressures increased to PAP systolic 37 ± 19 mmHg (p < 0.0001), diastolic 15 ± 10 mmHg (p = 0.006), and mean 24 ± 13 mmHg (p < 0.0001). Patients with elevated PAP diastolic at rest (>15 mmHg) demonstrated a greater increase in post-exercise PAP. The measurement of PAP with CardioMEMS is feasible immediately post-exercise. Despite being well-managed, patients had severely limited functional capacity. We observed a significant increase in PAP with ambulation which was greater in patients with higher baseline pressures.

Discussion on the zero-calibration and the zero line in the measurement of central venous pressure and invasive arterial blood pressure

To figure out the timing of zeroing and the location of the zero line in the central venous pressure (CVP) monitoring and invasive arterial blood pressure (IBP) monitoring, and to provide scientific and accurate data for patients management. The liquid vessel models were used to simulate the pressure measurement process of the continuous pressure monitoring system. Based on the theory of fluid mechanics and the knowledge of blood pressure physiology and cardiovascular anatomy, the composition and influencing factors of the pressure in the fluid-filled catheter system during the zeroing and placing the transducer in the zero line of CVP and IBP, were analyzed. The pressure in the liquid-filled catheter system was composed of atmospheric pressure, the pressure of pumping bag, the gravity of the water column (the vertical distance between the liquid level of Murphy's dropper and pressure transducer, ΔH), and the resistance of tube wall. This pressure value is set as a pressure of 0 mmHg (1 mmHg ≈ 0.133 kPa). In the process of pressure measurement, when the pressure transducer was placed at a horizontal position of 10 cm below the highest liquid level of the vessel, the pressure measured at different catheter tip positions was all 10 cmH2O (1 cmH2O ≈ 0.098 kPa); When the pressure transducer was placed at the horizontal position of the highest liquid level of the vessel, the measured pressure is 0 mmHg. Zeroing should repeatedly be performed only when one or more conditions (atmospheric pressure, pressure of pumping bag, gravity of ΔH water column and resistance of tube wall) are changed. In the measurement process, the pressure transducer should be placed at the zero line position at any time to eliminate the influence of hydrostatic pressure and to ensure the objective and accurate value.

Arterial cannulation in adult critical care patients: A comparative study between ultrasound guidance and palpation technique

ObjectiveTo compare first attempt success rate for ultrasound-guided (USG) versus direct palpation (DP) for radial, femoral, and dorsalis pedis artery cannulations in adult intensive care unit (ICU) patients. DesignProspective randomized clinical trial. SettingMixed adult ICU of a University Hospital. ParticipantsAdult patients (≥18 years) admitted to the ICU requiring invasive arterial pressure monitoring were included. Exclusion criteria were patients with a pre-existing arterial line and cannulated with other than a 20-gauge cannula for radial and dorsalis pedis artery. InterventionComparison of arterial cannulation by USG versus palpation technique in radial, femoral and dorsalis pedis arteries. Main variables of interestPrimary outcome was first attempt success rate, secondary outcomes were assessing time for cannulations, number of attempts, overall success rate, complications, and comparison of two techniques on patients requiring vasopressor. Results201 patients were enrolled in study, with 99 randomized to DP group and 102 to USG group. Arteries (radial, dorsalis pedis, femoral) cannulated in both groups were comparable (P = .193). Arterial line was placed on first attempt in 85 (83.3%) in USG group versus 55 (55.6%) in DP group (P = .02). Cannulation time in USG group was significantly shorter compared to DP group. ConclusionsIn our study, USG arterial cannulation, compared to palpatory technique, had a higher success rate at first attempt and a shorter cannulation time. Clinical Trial Registry of India numberCTRI/2020/01/022989.

A Case of Acute Intravascular Hemolysis During Dialysis: A Quiz

A Case of Acute Intravascular Hemolysis During Dialysis: A Quiz

Management of Heart Failure With Preserved Ejection Fraction in Elderly Patients: Effectiveness and Safety.

The proportion of the elderly population continues to increase due to the global increase in longevity. Heart failure with preserved ejection fraction (HFpEF) is common in the elderly due to cellular aging, myocardial stiffness, and multiple comorbidities. This age group is often under-represented in clinical trials. In this narrative review, we looked into the latest evidence-based lines of management of HFpEF in this vulnerable cohort. In this narrative review, we brought the latest evidence on the treatment of HFpEf in the elderly. We searched the largest three scientific databases (Pubmed, Google Scholar, and EMBASE) using thesearch words (elderly, HFpEF, heart failure with preserved ejection fraction, guidelines, treatment, and management) in different combinations. To date, screening for and treatment of the causes of HFpEF (such as hypertension, coronary artery disease [CAD], valvular heart disease, and cardiac amyloidosis) and associated comorbidities (such as diabetes mellitus [DM], iron deficiency, obesity, and thyroid dysfunction) are the main line of management of HFpEF. A multidisciplinary team, including an HF specialist cardiologist, an HF nurse, a geriatrician, a dietician, a psychologist, a physiotherapist, and an occupational therapist, should manage HFpEF elderly patients. Other specialist input may be needed according to the patient's requirements. The evidence on the effective management of HFpEF in the elderly age group is scarce and controversial. Some studied non-pharmacological approaches include supervised exercise training, pulmonary artery pressure monitoring, and the interatrial shunt device (an emerging modality that includes a small percutaneously inserted interatrial left to right valve aiming to reduce the left atrial and pulmonary wedge pressures). These modalities can only improve the symptoms and HF hospitalizations without robustly impacting cardiovascular (CV) death. Among the pharmacological approaches to treat HFpEF, only the sodium-glucose cotransporter 2 (SGLT-2) inhibitors proved efficacy in reducing the hard outcomes of CV death, HF hospitalizations, and urgent visits for HF when used in elderly HFpEF patients, irrespective of the presence of diabetes mellitus. Diuretics are only beneficial to alleviate the symptoms of fluid overload, with a risk of renal impairment in volume-depleted patients. The evidence on the effectiveness of other HF-specific disease-modifying agents in elderly HFpEF patients is controversial. Elderly patients have a higher risk of having side effects from HF medications due to the higher prevalence of polypharmacy, cognitive decline, and impairment of kidney and liver functions. Therefore, cautious initiation of HF treatment with a close follow-up of the blood pressure, liver functions, kidney functions, and electrolytes are of utmost importance.

A case report of mispositioned bilateral catheterization of the umbilical arteries in a neonate and review of the literature

Background: Arterial catheters are frequently needed to optimize the intensive care in the sick newborn. Umbilical Arterial Catheters (UAC) is more popular than peripheral arterial catheterization. They are utilized to provide continuous accurate arterial blood pressure monitoring, frequent assessment of gas exchange efficiency, frequent blood sampling and rarely for exchange blood transfusion. Umbilical Arterial Catheters may be used in emergencies to infuse fluids or medications in the absence of venous access. Malposition of the Umbilical Arterial Catheter requires immediate attention. The main complication of UAC malposition is obstruction of the arterial lumen of a small caliber branching artery. This may lead to impedance of arterial flow and predisposes to arterial thrombosis and embolism. Case Presentation: We present a rare case of bilateral UAC catheterization where the second umbilical artery was erroneously catheterized instead of the intended umbilical vein. Conclusion: This case reinforces the need for thorough assessment of the position and course of any recently inserted umbilical vascular catheter.

Experimental model of acute blood loss using rats for screening evalution of non-specific activity of infusion solutions

BACKGROUND: In accordance with the current regulations, preclinical evaluation of the effectiveness of plasma substitutes for acute blood loss is carried out mainly on large laboratory animals (dogs, pigs) using a wide range of methods for assessing the structural and functional state of organs and systems of a biological object. It requires large expenditure of material resources and time, which is impractical at the stage of screening the effectiveness of newly developed infusion agents. In this regard, an urgent task is to develop a standardized model of acute blood loss on small laboratory animals for screening evaluation of the specific activity of infusion solutions with a subsequent research involving large laboratory animals. It is advisable to use laboratory rats as a biological object as they are the most suitable of the group of small laboratory animals for similarity of physiological laboratory indicators with humans.&#x0D; AIM: To develop a model of acute blood loss using small laboratory animals for screening evaluation of specific infusion solution activity.&#x0D; MATERIALS AND METHODS: Experiments were carried out on rats of the Vistar line with a weight of 330 41 g. The animals were divided into 3 groups: 1 experimental (20 individuals with acute blood loss simulation without treatment), 2 experimental (20 individuals with acute blood loss simulation and its replacement with Rheopolyglucin), intact (10 individuals without modeling of blood loss). The study design included: general anesthesia (intramuscular injection Zoletil 100 and Xylazin 2% in a ratio of 1 : 5 at the rate of 0.01 ml/kg of weight), catheterization of the femoral artery followed by controlled hardware exfusion of blood at a rate of 0.5 ml/min until the establishment of persistent (for 2 minutes) arterial hypotension; hardware synchronous monitoring of mean arterial pressure (MAP) (by direct tonometry through the contralateral femoral artery); calculation of the percentage of blood loss from the estimated circulating blood volume (CBV) equal to 5% of the animals weight; heart rate (HR) (by electrocardiogram) during the first three hours after blood exfusion. In its capacity as a test drug Rheopolyglucin, which was administered through an arterial femoral catheter immediately after blood exfusion in volume and speed, equal to volume and speed of exfusion, was used. Additionally, for a comprehensive assessment of the mechanisms of maintaining hemodynamic parameters individual dynamic calculated indicators for each individual are proposed: the reduced shock volume of blood and the infusion efficiency indicator.&#x0D; RESULTS: All rats in the experimental group died, 25% of which 1720 minutes after blood exfusion, 75% in range from 45 to 90 minutes. Rheopoliglyukin infusion reduced the death of animals by up to 35% and delayed the average death time to 4555 minutes. A single exfusion of blood in rats resulted in loss of 79 ml of blood (4651% of circulating blood volume), which was accompanied by a decrease in mean arterial pressure and heart rate. Compensation for the decrease in circulating blood volume, including due to infusion, was manifested by an increase in these indicators. A sign of inefficiency of compensation was a slight increase of mean arterial pressure with dynamically increasing heart rate. It is proved that an increase in the values of calculated indicators (the given stroke volume of blood and the infusion efficiency indicator) are benchmarks for effective compensation of hemodynamic disorders, including as a result of infusion of hemodynamic drugs.&#x0D; CONCLUSIONS: The acute blood loss model with the calculation of the reduced shock volume of blood and the infusion efficiency index is advisable to use to assess the specific activity of infusion solutions in acute blood loss.

Cerebral pressure autoregulation and optimal cerebral perfusion pressure during neurocritical care of children with traumatic brain injury.

The management of cerebral perfusion pressure (CPP) is a challenge in children with traumatic brain injury (TBI) because the normal blood pressure is age dependent and the role of cerebral pressure autoregulation (CPA) is unclear. In this study, the authors aimed to examine the pressure reactivity index (PRx), CPP, optimal CPP (CPPopt), and deviations from CPPopt (ΔCPPopt) in a series of children with TBI generally and regarding age relations, temporal changes, and the influence on outcome. Intracranial pressure (ICP) and mean arterial pressure (MAP) monitoring data were collected during neurointensive care in 57 children who sustained a TBI and were ≤ 17 years of age. CPP, PRx, CPPopt, and ΔCPPopt (actual CPP - CPPopt) were calculated. Clinical outcomes at 6 months postinjury were dichotomized into favorable outcomes (Glasgow Outcome Scale [GOS] score 4 or 5) and unfavorable outcomes (GOS scores 1-3). The median patient age was 15 (range 0.5-17) years, and the median Glasgow Coma Scale motor score at admission was 5 (range 2-5). Forty-nine (86%) of the 57 patients had favorable outcomes. For the entire group, lower PRx (better preserved CPA) was associated with a more favorable outcome (p = 0.023, ANCOVA adjusted for age). When the children were divided into age groups, this finding was statistically significant in children ≤ 15 years of age (p = 0.016), but not in children ≥ 16 years (p = 0.528). In children ≤ 15 years, a lower proportion of time with ΔCPPopt < -10% was significantly associated with a favorable outcome (p = 0.038), but not in the older age group. Temporal analysis indicated that PRx was higher (more impaired CPA) from day 4 and CPPopt was higher from day 6 in the unfavorable outcome group compared with the favorable outcome group, although those findings were not significant. Impaired CPA is related to poor outcome, particularly in children ≤ 15 years of age. In that age group, actual CPP below the CPPopt level contributed significantly to unfavorable outcome, while levels close to or above the CPPopt were unrelated to outcome. CPPopt appears to be higher during the time period when CPA is most impaired.

CRT-300.11 90 -Day Outcomes of Pulmonary Artery Pressure Monitoring Device (CardioMEMS)

CRT-300.11 90 -Day Outcomes of Pulmonary Artery Pressure Monitoring Device (CardioMEMS)

Recent Advances in Remote Pulmonary Artery Pressure Monitoring for Patients with Chronic Heart Failure: Current Evidence and Future Perspectives.

Chronic heart failure (HF) is associated with high hospital admission rates and has an enormous burden on hospital resources worldwide. Ideally, detection of worsening HF in an early phase would allow physicians to intervene timely and proactively in order to prevent HF-related hospitalizations, a concept better known as remote hemodynamic monitoring. After years of research, remote monitoring of pulmonary artery pressures (PAP) has emerged as the most successful technique for ambulatory hemodynamic monitoring in HF patients to date. Currently, the CardioMEMS and Cordella HF systems have been tested for pulmonary artery pressure monitoring and the body of evidence has been growing rapidly over the past years. However, several ongoing studies are aiming to fill the gap in evidence that is still very clinically relevant, especially for the European setting. In this comprehensive review, we provide an overview of all available evidence for PAP monitoring as well as a detailed discussion of currently ongoing studies and future perspectives for this promising technique that is likely to impact HF care worldwide.

Cerebrovascular Pressure Reactivity According to Long-Pressure Reactivity Index During Spreading Depolarizations in Aneurysmal Subarachnoid Hemorrhage

BackgroundSpreading depolarization (SD) has been linked to the impairment of neurovascular coupling. However, the association between SD occurrence and cerebrovascular pressure reactivity as a surrogate of cerebral autoregulation (CA) remains unclear. Therefore, we analyzed CA using the long-pressure reactivity index (L-PRx) during SDs in patients with aneurysmal subarachnoid hemorrhage (aSAH).MethodsA retrospective study of patients with aSAH who were recruited at two centers, Heidelberg (HD) and Berlin (BE), was performed. Continuous monitoring of mean arterial pressure (MAP) and intracranial pressure (ICP) was recorded. ICP was measured using an intraparenchymal probe in HD patients and was measure in BE patients through external ventricular drainage. Electrocorticographic (ECoG) activity was continuously recorded between 3 and 13 days after hemorrhage. Autoregulation according to L-PRx was calculated as a moving linear Pearson’s correlation of 20-min averages of MAP and ICP. For every identified SD, 60-min intervals of L-PRx were averaged, plotted, and analyzed depending on SD occurrence. Random L-PRx recording periods without SDs served as the control.ResultsA total of 19 patients (HD n = 14, BE n = 5, mean age 50.4 years, 9 female patients) were monitored for a mean duration of 230.4 h (range 96–360, STD ± 69.6 h), during which ECoG recordings revealed a total number of 277 SDs. Of these, 184 represented a single SD, and 93 SDs presented in clusters. In HD patients, mean L-PRx values were 0.12 (95% confidence interval [CI] 0.11–0.13) during SDs and 0.07 (95% CI 0.06–0.08) during control periods (p < 0.001). Similarly, in BE patients, a higher L-PRx value of 0.11 (95% CI 0.11–0.12) was detected during SDs than that during control periods (0.08, 95% CI 0.07–0.09; p < 0.001). In a more detailed analysis, CA changes registered through an intraparenchymal probe (HD patients) revealed that clustered SD periods were characterized by signs of more severely impaired CA (L-PRx during SD in clusters: 0.23 [95% CI 0.20–0.25]; single SD: 0.09 [95% CI 0.08–0.10]; control periods: 0.07 [95% CI 0.06–0.08]; p < 0.001). This group also showed significant increases in ICP during SDs in clusters compared with single SD and control periods.ConclusionsNeuromonitoring for simultaneous assessment of cerebrovascular pressure reactivity using 20-min averages of MAP and ICP measured by L-PRx during SD events is feasible. SD occurrence was associated with significant increases in L-PRx values indicative of CA disturbances. An impaired CA was found during SD in clusters when using an intraparenchymal probe. This preliminary study validates the use of cerebrovascular reactivity indices to evaluate CA disturbances during SDs. Our results warrant further investigation in larger prospective patient cohorts.

Experience with clinical cerebral autoregulation testing in children hospitalized with traumatic brain injury: Translating research to bedside.

To report our institutional experience with implementing a clinical cerebral autoregulation testing order set with protocol in children hospitalized with traumatic brain injury (TBI). After IRB approval, we examined clinical use, patient characteristics, feasibility, and safety of cerebral autoregulation testing in children aged <18 years between 2014 and 2021. A clinical order set with a protocol for cerebral autoregulation testing was introduced in 2018. 25 (24 severe TBI and 1 mild TBI) children, median age 13 years [IQR 4.5; 15] and median admission GCS 3[IQR 3; 3.5]) underwent 61 cerebral autoregulation tests during the first 16 days after admission [IQR1.5; 7; range 0-16]. Testing was more common after implementation of the order set (n = 16, 64% after the order set vs. n = 9, 36% before the order set) and initiated during the first 2 days. During testing, patients were mechanically ventilated (n = 60, 98.4%), had invasive arterial blood pressure monitoring (n = 60, 98.4%), had intracranial pressure monitoring (n = 56, 90.3%), brain-tissue oxygenation monitoring (n = 56, 90.3%), and external ventricular drain (n = 13, 25.5%). Most patients received sedation and analgesia for intracranial pressure control (n = 52; 83.8%) and vasoactive support (n = 55, 90.2%) during testing. Cerebral autoregulation testing was completed in 82% (n = 50 tests); 11 tests were not completed [high intracranial pressure (n = 5), high blood pressure (n = 2), bradycardia (n = 2), low cerebral perfusion pressure (n = 1), or intolerance to blood pressure cuff inflation (n = 1)]. Impaired cerebral autoregulation on first assessment resulted in repeat testing (80% impaired vs. 23% intact, RR 2.93, 95% CI 1.06:8.08, p = 0.03). Seven out of 50 tests (14%) resulted in a change in cerebral hemodynamic targets. Findings from this series of children with TBI indicate that: (1) Availability of clinical order set with protocol facilitated clinical cerebral autoregulation testing, (2) Clinicians ordered cerebral autoregulation tests in children with severe TBI receiving high therapeutic intensity and repeatedly with impaired status on the first test, (3) Clinical cerebral autoregulation testing is feasible and safe, and (4) Testing results led to change in hemodynamic targets in some patients.

Association between temporal patterns of baroreflex sensitivity after traumatic brain injury and prognosis: a preliminary study

IntroductionTraumatic brain injury (TBI) may lead to an increase in intracranial pressure (ICP) as well as impairment of cerebral vascular reactivity and the autonomic nervous system. This study aimed to investigate individual patterns of changes in baroreflex sensitivity (BRS) along with the assessment of pressure reactivity index (PRx) and ICP after TBI.Materials and methodsTwenty-nine TBI patients with continuous arterial blood pressure (ABP) and ICP monitoring were included. BRS was calculated using the sequential cross-correlation method. PRx was estimated using slow-wave oscillations of ABP and ICP. Outcome was assessed using the Glasgow Outcome Scale.ResultsPooled data analysis of the lower breakpoint during the week that followed TBI revealed that BRS reached a minimum about 2 days after TBI. In patients with good outcome, there was a significant increase in BRS during the 7 days following TBI: rp = 0.21; p = 0.008 and the temporal changes in BRS showed either a “U-shaped” pattern or a gradual increase over time. The BRS value after 1.5 days was found to be a significant predictor of mortality (cut-off BRS = 1.8 ms/mm Hg; AUC = 0.83). In patients with poor outcome, ICP and PRx increased while BRS remained low.ConclusionsWe found an association between temporal patterns of BRS and prognosis in the early days following TBI. Further research in a larger cohort of patients is needed to confirm the weight of these preliminary observations for prediction of prognosis in TBI patients.

Errors in pressure measurements due to changes in pressure transducer levels during adult cardiac surgery: a prospective observational study

BackgroundBlood pressure measurement is an essential element during intraoperative patient management. However, errors caused by changes in transducer levels can occur during surgery.MethodsThis single center, prospective, observational study enrolled 25 consecutive patients scheduled for elective cardiac surgery with invasive arterial and central venous pressure (CVP) monitoring. Hydrostatic pressures caused by level differences (leveling pressure) between a reference point (on the center of the left biceps brachii muscle) and the transducers (fixed on the right side of the operating table) for arterial and central lines were continuously measured using a leveling transducer. Adjusted pressures were calculated as measured pressure – leveling pressure. Hypotension (mean arterial pressure < 80, <70, and < 60 mmHg), and CVP (< 6, ≥6 and < 15, or ≥ 15 mmHg) and pulmonary artery pressure (PAP, mean > 20 mmHg) levels were determined using unadjusted and adjusted pressures.ResultsTwenty-two patients were included in the analysis. Leveling pressure ≥ 3 mmHg and ≥ 5 mmHg observed at 46.0 and 18.7% of pooled data points, respectively. Determinations of hypotension using unadjusted and adjusted pressures showed disagreements ranging from 3.3 to 9.4% depending on the cutoffs. Disagreements in defined levels of CVP and PAP were observed at 23.0 and 17.2% of the data points, respectively.ConclusionsThe errors in pressure measurement due to changes in transducer level were not trivial and caused variable disagreements in the determination of MAP, CVP, and PAP levels. To prevent distortions in intraoperative hemodynamic management, strategies should be sought to minimize or adjust for these errors in clinical practice.Trial registrationcris.nih.go.kr (KCT0006510).