Hemodynamic Derangements Research Articles

Peripheral baroreflex and chemoreflex function after eversion carotid endarterectomy

This study assessed the long-term effect of the eversion technique for carotid endarterectomy (e-CEA) on arterial baroreflex and peripheral chemoreflex function. The study included 13 patients who underwent, between 2001 and 2006, bilateral e-CEA and 16 who underwent bilateral standard CEA (s-CEA) to eliminate the complicating effects of intact contralateral carotid sinus function. Exclusion criteria were age >70 years, diabetes mellitus, chronic pulmonary disease, ischemic cardiac disease or medical therapy with β-blockers, cardiac arrhythmia, neurologic deficits, carotid restenosis, and previous neck or chest surgery or irradiation. Young and aged-matched healthy individuals were recruited as controls. All patients underwent standard cardiovascular reflex tests, including lying-to-standing, orthostatic hypotension, deep breathing, and Valsalva maneuver. Autonomic cardiovascular modulation was indirectly evaluated by spectral analysis of heart rate variability and systolic arterial pressure variability. The chemoreflex sensitivity to hypoxia was obtained during classic rebreathing tests from the slopes of the linear regression of minute ventilation (VE) vs arterial oxygen saturation measured by pulse oximetry (SpO2%) and partial pressure of end-tidal oxygen (PetO2). Patients (16 men; age, 62.4 ± 8.0 years) were enrolled after a mean interval of 24 ± 17 months from the last CEA. All were asymptomatic, and results of standard tests were negative. Residual baroreflex performance was documented in both patient groups, although reduced, compared with young controls. Notably, baroreflex sensitivity (msec/mm Hg) was better maintained after e-CEA than after s-CEA at rest (young controls, 19.93 ± 9.50; age-matched controls, 7.75 ± 5.68; e-CEA, 13.85 ± 14.54; and s-CEA, 3.83 ± 1.15; analysis of variance [ANOVA], P = .001); and at standing (young controls, 7.83 ± 2.55; age-matched controls, 3.71 ± 1.59; e-CEA, 7.04 ± 5.62; and s-CEA 3.57 ± 3.80; ANOVA, P = .001). Similarly, chemoreflex sensitivity to hypoxia was maintained in both patient groups, which did not differ from each other, and was reduced compared with controls (controls vs patient groups ΔVE/ΔSpO2: -1.37 ± 0.33 vs -0.33 ± 0.08 and SpO2% -0.29 ± 0.13 L/min; P = .002; ΔVE/ΔPetO2: -0.20 ± 0.1 vs -0.01 ± 0.0 and -0.07 ± 0.02 L/min/mm Hg; P = .04, ANOVA with least significant difference correction for multiple comparisons). Our data show that e-CEA, even when performed on both sides, preserves baroreflexes and chemoreflexes and, therefore, does not confer permanent carotid sinus denervation. Also, e-CEA does not increase long-term arterial pressure variability, and this suggests that perioperative hemodynamic derangements can be attributed to the temporary effects of surgical trauma.

Micro-RNA-451 and Measures of Hemolysis Associated with Left Ventricular Assist Device Implantation

Purpose Hemolysis is a well-known complication of left ventricular assist device (LVAD) implantation that contributes to hemodynamic derangement and end-organ damage. Micro-RNAs (miRs) are non-coding RNA species that control gene expression by targeting specific messenger RNAs for degradation. MiR-451 is specifically expressed in erythrocyte precursors and mature red blood cells. The goal of this study was to evaluate changes in circulating miR-451 levels before and after LVAD implantation and whether these changes associate with measures of hemolysis. Methods and Materials Blood samples were obtained from healthy volunteers and from patients with advanced heart failure at the time of LVAD implantation and at the time of explantation. Absorbance at 414 nm (ABS 414 ), the maximum absorbance of hemoglobin, was measured in plasma. RNA was extracted from plasma and RT-PCR specific for miR-451 was performed. Results The mean duration of LVAD therapy was 488 ± 179 days. Plasma ABS 414 correlated with the degree of hemolysis of blood that was mechanically disrupted in vitro. The mean plasma ABS 414 was increased 3.4-fold after LVAD implantation compared to paired pre-implantation samples (P=0.05), which had a mean plasma ABS 414 comparable to non-hemolyzed control samples. Lactate dehydrogenase and bilirubin, commonly used tests for hemolysis, each correlated poorly with plasma ABS 414 among these patients (R2=0.20 and 0.22, respectively; each P nonsignificant) and did not differ between pre- and post-LVAD samples. Compared to control plasma, miR-451 levels were roughly 40% higher in samples from heart failure patients before LVAD placement. Plasma miR-451 levels increased 164-fold after LVAD implantation compared to paired pre-implant samples (Mann-Whitney P= 0.002). Conclusions Micro-RNAs hold promise as biomarkers in heart failure. MiR-451 may be a new marker of hemolysis related to LVAD implantation that performs favorably compared to traditional markers.

Characteristics of PAH Patients Treated Initially with Parenteral Prostanoids Differ from Those Treated Initially with Oral Therapy Despite Matching for REVEAL Risk Score

Purpose Controversy exists regarding whether initial treatment with parenteral prostanoids results in superior outcome to initial treatment with oral agents in patients with PAH. In preparation for a comparative effectiveness analysis we compared characteristics of patients in the REVEAL registry who were matched for REVEAL risk score. Methods and Materials The REVEAL registry was queried in order to compare characteristics of newly diagnosed patients initiating parenteral prostanoids (Group A) with a set of patients initiating oral agents (Group B) who were matched by REVEAL risk score. Baseline characteristics were compared with P values for categorical variables calculated from the chi-square test and P values for continuous variables calculated by t test or Wilcoxon-Mann-Whitney test. Results Group A differed from Group B, including younger age, higher heart rate, preponderance of FC IV and IPAH, better DLCO, and more severe hemodynamic derangement ( Table ). Conclusions Despite matching for REVEAL risk score, patients initiating parenteral prostanoids differ in important ways from those initiating oral therapy. This analysis provides insight into decision making with regard to prostanoid initiation and illustrates the difficulty of attempting to perform comparative effectiveness research in the absence of a randomized controlled trial design. Characteristics of Group A and Group B Characteristic IV/SC PGI2 Group Oral Only Group P value Patients, n 144 144 - Risk Score, mean±SD 9±2 9±2 - Age (yrs), mean±SD 50.3±15.2 56.3±16.0 .001 Male, n (%) 24 (16.7) 34 (23.6) .14 Etiology, n (%) IPAH 86 (59.7%) 58 (40.3%) .002 APAH-CTD 34 (23.6%) 48 (33.3%) - APAH-PoPH 7 (4.9%) 15 (10.4%) - NYHA FC III, n (%) 59 (44.0%) 82 (67.2%) .001 NYHA FC IV, n (%) 50 (37.3%) 12 (9.8%) - DLCO (%), mean±SD 55±24 46±18 .004 HR (bpm), mean±SD 89±16 84±15 .008 mRAP (mmHg) in past yr, mean±SD 13±6 9±5 PVR (Wood Units), mean±SD 13.6±5.5 11.2±6.5 Nt-BNP (pg/ml), median 2221 1718 .43

Common carotid and brachial artery hemodynamic alterations in periodontal disease

In patients affected by periodontal disease, hypertension and systemic inflammation might cause an arterial hemodynamic derangement; this, in turn, can act as a mediator of the atherogenic process often seen in these patients. This study aimed at a comprehensive hemodynamic evaluation in periodontal patients. Fourty-eight subjects participating to a cardiovascular prevention programme were enrolled. Periodontitis, classical risk factors for atherosclerosis, and shear and tensile forces in both carotid and brachial arteries were evaluated. Calculated periodontal indexes were plaque, gingival and pocket deep (PD) indexes. Simple and multiple regression analyses were performed. Afterwards, 30 of them with normal PD index were compared with 30 carefully - matched patients with periodontitis. Brachial and carotid parietal tension were significantly associated with periodontal indexes, especially PD-Sum, in both simple (r=0.42, p<0.001 for carotid artery and r=0.36, p<0.02 for brachial artery) and multiple regression analyses. Shear stress gave similar results. In case-control analysis, shear stress was lower by 15% and 30%, respectively, in carotid and brachial artery in patients with high PD; common carotid parietal tension was higher. Arterial stiffness resulted not associated with periodontitis. Periodontal disease is associated to a complex atherosclerotic prone hemodynamic derangement, particularly in large elastic arteries.

Abstract 13: Asymmetry of Deep Medullary Veins in Susceptibility Weighted Imaging is associated with Poor Collaterals in Patients with Acute Ischemic Stroke

Background: Susceptibility Weighted Imaging (SWI) is a high spatial resolution of MR imaging technique showing magnetic inhomogeneity that could demonstrate increased oxygen extraction in ischemic hemisphere. The aim of this study was to investigate whether the asymmetry of deep medullary veins (DMVs) on SWI could indicate the poor collateral flow, which results in the hemodynamic derangement in acute ischemic stroke. Methods: Consecutive 132 patients with acute middle cerebral artery infarction within 6 hours from symptom onset were included. The DMVs of ipsilesional region of interests (ROIs) and contralateral ROIs were evaluated; score 0: no DMVs, score 1: moderately visibility of DMVs, and score 2: obviously visibility of DMVs. Asymmetry is defined as the difference in the scores of DMVs between both hemispheres. Collateral status on conventional angiography was graded 0 to 4 based on the ASTIN/SIR collateral flows grading system. Poor collateral flow is defined as grade 0-1. Early neurological deterioration was defined as an increase in the NIHSS score by ≥4 points during the first 48 hours after admission. Multivariable logistic regression analysis was used to examine the association between the presence of asymmetry of DMVs and poor collateral flow or clinical outcomes. Results: Of 132 patients, 74 (56.1%) had asymmetry of DMVs. Asymmetry of DMVs was independently associated with the poor collateral status (OR; 42.1, 95% confidential interval 1.99.-89.81, p=0.02) after adjusting confounders. Moreover, patients with asymmetry of DMVs were likely to have more profound infarction growth (OR; 6.01, 95% CI, 1.21-29.88, p=0.03) and results in the early neurological deterioration (OR; 5.49, 95% CI, 1.21-28.57, p=0.03). Conclusion: Asymmetry of DMVs is independently associated with poor collateral status which affects the clinical deterioration in patients with acute middle cerebral artery stroke.

Right Ventricular Outflow Tract Systolic Excursion: A Distinguishing Echocardiographic Finding in Acute Pulmonary Embolism

Even though chronic pulmonary hypertension (cPH) and acute pulmonary embolism (aPE) increase pulmonary vascular resistance and result in right ventricular (RV) dilatation and systolic dysfunction; both conditions operate through drastically different mechanisms. Unfortunately, simple echocardiographic examination might be insufficient to distinguish both entities. This study attempted to determine which objective measures would be useful in differentiating aPE from cPH. Standard measures of main RV as well as RV outflow tract (RVOT) size and systolic performance calculations were retrospectively measured from 15 patients with confirmed aPE by chest computed tomography and compared with similar data collected from the same number of age-matched patients with moderate (mcPH), severe (scPH), and patients without PH. Although a positive McConnell sign was seen in 60% of aPE patients and in 17% of the cPH patients, all aPE had a profound reduction in RVOT systolic excursion when compared with cPH patients. Furthermore, maximal tricuspid annular plane systolic excursion, velocity time integral of the RVOT ejection signal, end-systolic or end-diastolic RV to left ventricle (LV) dimension ratio were not useful to distinguish aPE from any of the 2 forms of cPH. This study demonstrated that measurement of RVOT systolic excursion not only is feasible but also extremely useful in identifying aPE and it is particularly helpful in differentiating it from patients with either mcPH or scPH. This variable might be useful to estimate the global impairment in RV contractility and acute hemodynamic derangement seen in aPE.

Point-of-Care Ultrasonography in Assessing Fluid Responsiveness in Sepsis Patients: Sonographer Characteristics, Noninferential Statistics, and Study Design: Answers to the September 2012 Journal Club Questions

Q1. Sepsis is a complex cascade of immunologic mechanisms related to systemic infection. There are many causes of sepsis, and many of its hemodynamic and metabolic derangements can occur concomitantly or independently. To counter toxin-mediated vasodilatation, early goal-directed therapy (EGDT) advocates aggressive fluid resuscitation. However, several criticisms have been made about the use of central venous pressure (CVP) in assessing fluid responsiveness and guiding EGDT. The Figure below highlights the major mechanisms in sepsis, and how fluid responsiveness is assessed with CVP and inferior vena cava (IVC) measurement.

Causes and treatment of oedema in patients with heart failure

Oedema is one of the fundamental features of heart failure, but the pathophysiology of oedema varies. Patients present along a spectrum ranging from acute pulmonary oedema to gross fluid retention and peripheral oedema (anasarca). In patients with pure pulmonary oedema, the problem is one of acute haemodynamic derangement; the patient does not have excess fluid, but pulmonary venous pressure rises such that the rate of fluid transudation into the interstitium of the lung exceeds the capacity of the pulmonary lymphatics to drain away the fluid. Conversely, in patients with peripheral oedema, the problem is one of fluid retention. Understanding the causes of oedema will enable straightforward, correct management of the condition. For patients with acute pulmonary oedema, vasodilatation is important to reduce cardiac filling pressures. For patients with fluid retention, removing the fluid, using either diuretics or mechanical means, is the most important consideration.

Evaluation of Propofol as a General Anesthetic Agent for Minor Oral Surgical Procedure

Nausea and vomiting following anesthesia is a distressing problem for the patient as it increases the recovery time, intensity of nursing care and delays discharge. The aim of randomized controlled single blind study is to evaluate the efficacy and safety of subhypnotic doses of propofol for the prevention of postoperative nausea and vomiting (PONV) in day care management of cases in oral and maxillofacial surgeries. Twenty-five patient of ASA-1 with age ranging from 12 to 40 years were scheduled for various maxillofacial surgical cases like fracture, cyst enucleation, surgical removal of 3rd molar, etc. were given propofol at the dose of 2 to 2.5 mg/kg as induction dose and sedation was maintained with the dose 5 to 10 mg/min. There was no significant effect on heart rate, systolic and diastolic blood pressure, respiratory rate and oxygen saturation intraoperatively. In conclusion, a subhypnotic dose of propofol is fast acting, safe and easily controllable, short acting general anesthetic agent with rapid recovery. The study found that the PONV was significantly reduced in the patient with propofol, no hemodynamic derangements were noted in the postoperative period.

Current strategies for preventing renal dysfunction in patients with heart failure: a heart failure stage approach

Renal dysfunction is common during episodes of acute decompensated heart failure, and historical data indicate that the mean creatinine level at admission has risen in recent decades. Different mechanisms underlying this change over time have been proposed, such as demographic changes, hemodynamic and neurohumoral derangements and medical interventions. In this setting, various strategies have been proposed for the prevention of renal dysfunction with heterogeneous results. In the present article, we review and discuss the main aspects of renal dysfunction prevention according to the different stages of heart failure.

Pericardial tamponade caused by massive fluid resuscitation in a patient with pericardial effusion and end-stage renal disease -A case report-

Pericardial tamponade can lead to significant hemodynamic derangement including cardiac arrest. We experienced a case of pericardial tamponade in a patient with end-stage renal disease. Hemodynamic changes occurred by unexpectedly aggravated pericardial effusion during surgery for iatrogenic hemothorax. We quickly administered a large amount of fluids and blood products for massive bleeding and fluid deficit due to hemothorax. Pericardial effusion was worsened by massive fluid resuscitation, and thereby resulted in pericardial tamponade. Hemodynamic parameters improved just after pericardiocentesis, and the patient was transferred to the intensive care unit.

Comparison of the Flexi laryngeal mask airway vs. endotracheal intubation for paediatric ophthalmic surgery

Background: The study aims at assessing the advantages of Flexi laryngeal mask airway (Flexi LMA) over endotracheal intubation in minimizing the pressor response as well as the rise in intraocular pressure in paediatric patients undergoing ophthalmic operations. Method: Sixty paediatric patients aged 4-12 years of ASA grade I and II meant for ophthalmic surgeries were divided into two groups of 30 patients each by a computer generated table. Group I patients underwent Flexi Laryngeal mask airway insertion and group II patients received endotracheal intubation. All the patients received similar premedication and anaesthetic drugs on per kg body weight basis. Patients were induced with Propofol and were maintained on Oxygen, nitrous oxide, Sevoflurane and rocuronium bromide. Changes in heart rate, mean arterial pressure and intraocular pressure were noted at different intervals which were markedly different in the two groups. Values so obtained were analysed using students t test and Z test respectively. A p value < 0.05 was considered to be statistically significant. Results: Similar but marked attenuated pattern of response was seen in group I patients compared to group II patients. Statistically significant difference between the two groups were seen in mean arterial blood pressure, heart rate and intra-ocular pressure(p < 0.05). Conclusion: Thus the use of Flexi LMA may offer some noticeable advantages over endotracheal intubation, especially for glaucoma patients as well as for those with some other associated congenital anomaly like The aim of this study was to assess the use of Flexi Laryngeal Mask Airway (Flexi LMA) as an alternative to avoid or to attenuate various noxious responses of endotracheal intubation including haemodynamic derangement and to intraocular pressure changes in paediatric patients who underwent ophthalmic surgeries. II. Method After obtaining approval from the ethical committee, sixty paediatric patients of ASA grade I and II scheduled to undergo ophthalmic surgeries under general anaesthesia, were studied after obtaining informed written consent from patient's parent. Patients in this study included those who had to undergo strabismus surgery, trabeculectomy, cataract surgery and Intraocolar lens implantation (I.O.L.). The patients were divided into two groups of 30 patients each by a computer generated table. Group I consisted of patients who were subjected to Flexi LMA insertion and Group II had undergone conventional laryngoscopy and endotracheal intubation (ETT). Patients with associated cardiovascular problems, upper respiratory tract infection, raised intraocular

Abstract 64: Association Between Blood Pressure Measurements, Vasopressor Use and Outcome in Post--Cardiac Arrest Patients Treated with Therapeutic Hypothermia from 4 Sites (COMICA Study Group)

Introduction: Specific hemodynamic optimization strategies have not been clearly described nor defined for post-cardiac arrest syndrome (PCAS) patients undergoing therapeutic hypothermia (TH). Hypothesis: Patients who suffer worse neurologic outcomes will have more significant hemodynamic derangements in the early hours post-arrest than those with good neurologic outcome. Methods: This is a collaborative study amongst 4 centers with aggressive TH protocols (BID, Penn, Pitt, VCU). It is a secondary analysis from prospectively collected data of out-of-hospital cardiac arrest patients who underwent TH. The primary outcome is neurologic status at hospital discharge measured as cerebral performance category (CPC), dichotomized into “good” (1 or 2) or “poor” (3, 4, or 5). Demographic information, initial rhythm and co-morbid conditions were obtained. Study variables were abstracted at baseline, 12, 24, 36 and 48 hrs. Variables recorded were systolic blood pressure (SBP) at baseline; MAP at each time point; worst, highest and lowest mean arterial pressure (MAP) for each 24 hr interval; vasopressor use. Results: A total of 111 patients were enrolled. Patients were 61 ± 16.8 years, 59.5% male, with an initial rhythm of VF/VT in 50.5% of cases. The initial SBP for patients with good vs. poor outcome was 150 ± 37 mmHg vs. 128 ± 32 mmHg respectively (p=0.037). Patients in both groups had comparable MAPs at 12 hrs (91 vs. 87, p= 0.34) and at 36 hrs (86 vs. 81, p=0.113); however, the vasopressor use at these time points differed. At 12 hrs, vasopressors were used in 20% of patients with good outcome, versus 43.4% of patients with poor outcome (p=0.017). At 36 hrs, 31.4% of patients with a good outcome were on vasopressors vs. 50.7% with a poor outcome (p=0.06). In the first 24 hrs, subjects with good and poor outcome had equal distributions of their worst MAPs into the “low” (90 mmHg) categories. Conversely, in the second 24 hrs, patients with a poor outcome had a higher proportion of patients where their worst MAP was “low” versus those who had a good outcome (67% vs. 76%, ns). Conclusions: Patients with poor neurologic outcomes have lower initial SBPs and a higher percentage of vasopressor use during TH versus patients with good neurologic outcomes.

Pathological bacterial translocation in cirrhosis: pathophysiology, diagnosis and clinical implications

Bacterial translocation (BT) is defined by the passage of viable indigenous bacteria from the intestinal lumen to mesenteric lymph nodes (MLNs) and other territories, and its diagnostic criteria rely on the isolation of viable bacteria in MLNs. Small intestinal overgrowth, increased intestinal permeability and immunological alterations are the main factors involved in its pathogenesis. BT is obviously difficult to identify in patients with cirrhosis, and alternative methods have been proposed instead. Bacterial DNA detection and species identification in serum or ascitic fluid has been proposed as a reliable marker of BT. Bacterial products, such as endotoxin, or bacterial DNA can translocate to extra-intestinal sites and promote an immunological response similar to that produced by viable bacteria. Therefore, pathological BT plays an important role in the pathogenesis of the complications of cirrhosis, not only in infections, but by exerting a profound inflammatory state and exacerbating the haemodynamic derangement. This may promote in turn the development of hepatorenal syndrome, hepatic encephalopathy and other portal hypertension-related complications. Therapeutic approaches for the prevention of BT in experimental and human cirrhosis are summarized. Finally, new investigations are needed to better understand the pathogenesis and consequences of translocation by viable bacteria (able to grow in culture), or non-viable BT (detection of bacterial fragments with negative culture) and open new therapeutic avenues in patients with cirrhosis.

Chronic Direct Renin Inhibition With Aliskiren Prevents the Development of Hypertension in Cyp1a1-Ren2 Transgenic Rats With Inducible ANG II-Dependent Hypertension

IntroductionThis study was performed to determine whether chronic direct renin inhibition can prevent the development of slowly progressive angiotensin (ANG) II-dependent hypertension and the associated derangements in renal function in Cyplal-Ren2 transgenic rats with inducible expression of the Ren2 gene. MethodsMale Cyplal-Ren2 rats (n=6) were fed a normal diet containing 0.15% indole-3-carbinol (I3C) for 16days to induce slowly progressive ANG II-dependent hypertension. Conscious systolic blood pressure was measured daily using tail-cuff plethysmography. The rats were then anesthetized with pentobarbital sodium and surgically prepared for the measurement of mean arterial pressure (MAP) and renal hemodynamics and excretory function. ResultsIn rats induced with I3C, systolic blood pressure increased by day 3 (130 ± 7–160 ± 5mm Hg, P < 0.01) and continued to increase to 191 ± 6mm Hg (P < 0.001) by day 16. In a separate group of rats (n=6), chronic administration of the direct renin inhibitor, aliskiren (30mg/kg/d, sc), prevented the development of hypertension (113 ± 5 versus 114 ± 5mm Hg, not significant). Rats treated with aliskiren exhibited significantly lower mean arterial pressure (138 ± 4 versus 201 ± 6mm Hg, P < 0.001), renal vascular resistance (23 ± 4 versus 38 ± 3mm Hg/mL/min · g, P < 0.01), urine flow (17.6 ± 1.4 versus 25.1 ± 2.9 μL/min, P < 0.05) and urinary sodium excretion (1.11 ± 0.32 versus 2.35 ± 0.28 μEq/min, P < 0.05) and higher renal plasma flow (4.22 ± 0.23 versus 2.56 ± 0.21mL/min · g, P < 0.01) and glomerular filtration rate (1.19 ± 0.07 versus 0.78 ± 0.08mL/min · g, P< 0.01), compared with induced rats not treated chronically with aliskiren. ConclusionsThe present findings demonstrate that chronic direct renin inhibition with aliskiren prevents the development of ANG II-dependent hypertension and the associated derangements in renal hemodynamics and excretory function in Cyplal-Ren2 transgenic rats.

401 Cardiovascular Indices Measured by a Noninvasive Doppler Ultrasonography Cardiac Output Monitor in Patients With Stage 2 Hypertension

Study Objective: Hypertensive patients either have increased systemic vascular resistance or increased cardiac output, or both. The exact prevalence of these pathophysiological derangements, and their relative contribution to hypertension, are not known. Study Objectives: To use a noninvasive Doppler ultrasonography cardiac output monitor to measure haemodynamic parameters and determine the relative derangements of cardiac output and systemic vascular resistance in emergency department patients with Stage 2 hypertension. Methods: Patients aged 18 years or above who attended the emergency department (ED) with systolic blood pressure> 160 or diastolic blood pressure >100 in 2 or more measurements at least 20 minutes apart were included. Research assistants collected demographic and clinical data and measured the cardiac output and systemic vascular resistance of these patients with a noninvasive Doppler ultrasonography cardiac output monitor. Patients were followed up within 2 weeks. Those who did not have documented increased blood pressure (Stage 2) in 2 or more different occasions were excluded. The patients' body surface area (BSA) was calculated to obtain the cardiac index (CI) and the systemic vascular resistance index (SVRI); where CI = cardiac output/BSA and SVRI = systemic vascular resistance/BSA. Results: Forty-nine patients were included. Mean age (+/− SD) was 66.5 +/− 12.5 years and 59.2% were females. 7 (14.3%) had either high cardiac output or high CI; 41(83.7%) had either high systemic vascular resistance or high SVRI; one had normal haemodynamics; 18 (36.7%) had either low cardiac output or low CI; and 3 (6.1%) had low SVRI. The prevalence of haemodynamic derangement subtypes was as follows: 4 (8.2%) with systemic vascular resistance normal, cardiac output high; 39 (79.5%) with systemic vascular resistance high, cardiac output normal; 4 (8.2%) with systemic vascular resistance and cardiac output normal; 2 (4.1%) with systemic vascular resistance high, cardiac output low. Conclusion: In ED patients with Stage 2 hypertension, about 80% have increased systemic vascular resistance. If clinicians choose anti-hypertensive therapy aiming at reducing systemic vascular resistance, it may result in a much higher likelihood of effective blood pressure control.

Echocardiography-guided biventricular pacemaker optimization: role of echo Doppler in hemodynamic assessment and improvement

In spite of improvements in heart failure management and increasing utilization of cardiac resynchronization therapy (CRT), approximately 30–40% of CRT patients remain nonresponders and 50% or more are echocardiographic nonresponders (defined as less than 15% reduction in left ventricular end systolic volume post-CRT). Optimization guided by echocardiography has been studied as one of the methods to improve the nonresponder rate to CRT. Echo-guided biventricular (Biv) pacemaker optimization has been associated with improvement in acute cardiac hemodynamics and improvement in functional class. In this review, the authors discuss various methods to optimize Biv pacemaker by echocardiography, recent advances in pacemaker optimization and the limitations of echocardiography. The authors also demonstrate complex hemodynamic derangements in heart failure via multiple case examples highlighting the role of comprehensive echo Doppler in elucidating cardiac hemodynamics encountered in CRT nonresponders, as well as tailoring of Biv pacemaker optimization to the underlying physiologic derangement.

Monitoring peripheral perfusion in critically ill patients at the bedside

The goal of circulatory monitoring is the use of an accurate, continuous and noninvasive method that can easily assess tissue perfusion under clinical conditions. As peripheral tissues are sensitive to alterations in perfusion, the noninvasive monitoring of peripheral circulation could be used as an early marker of systemic haemodynamic derangement. We, therefore, aim to discuss the currently available methods that can be used at the bedside as well as the role of peripheral perfusion monitoring in critically ill patients. The deterioration of peripheral circulation has frequently been observed in critically ill patients with the use of subjective assessment and several optical techniques. In various patient categories, more severe and persistent alterations have been associated with worse outcomes, and these associations were independent of systemic haemodynamic parameters. Interventions aimed at systemic parameters have an unpredictable effect on peripheral circulation parameters, especially during hyperdynamic conditions. Thus, it appears that changes in peripheral perfusion reflect changes in regional vasomotor tone rather than systemic blood flow. Subjective assessments and optical techniques provide important information regarding peripheral circulation. Moreover, these techniques are relatively easy to implement and interpret at the bedside and can be applied during acute conditions. Further research is warranted to investigate the effects of therapeutic interventions on peripheral perfusion parameters and patient outcome.

Prognostic implications of renal dysfunction in patients hospitalized with heart failure: data from the last decade of clinical investigations

Numerous studies over the last decade have demonstrated that renal dysfunction and worsening renal function (WRF) are common in patients hospitalized for heart failure (HHF) and appear to be associated with poor in-hospital and post-discharge outcomes. Unfortunately, its etiology has not been completely understood, and its prediction during hospitalization remains challenging. The evaluation of renal impairment during hospitalization should take into consideration the underlying renal substrate (e.g., predisposing clinical comorbidities such as diabetes and hypertension), initiating mechanisms (e.g., in-hospital therapies such as diuretics), and amplifying factors (neurohormonal and hemodynamic profile changes). Various patterns of WRF may have different prognostic implications and may require different therapeutic approaches. WRF may be initially classified by duration (transient vs. persistent) and by etiology (elevated venous pressures vs. arterial underfilling). Other critical contributing factors during hospitalization include progressive left ventricular dysfunction, neurohormonal activation, and medications. Transient WRF as a result of aggressive therapy targeting congestion may not be associated with poor outcomes. Persistent WRF seen in patients with severe hemodynamic derangements may be associated with poor post-discharge prognosis. Future investigations must clarify the pathophysiological correlates of various patterns of WRF. To date, there is an unmet clinical need to achieve adequate control over congestion while preserving renal function in HHF patients. Thus, the aim of this review is to provide an in-depth and critical interpretation of the available data on the prognostic importance of RD and WRF during hospitalization in an effort to improve HF management.

The PiCCO Monitor: A Review

Advanced haemodynamic monitoring remains a cornerstone in the management of the critically ill. While rates of pulmonary artery catheter use have been declining, there has been an increase in the number of alternatives for monitoring cardiac output as well as greater understanding of the methods and criteria with which to compare devices. The PiCCO (Pulse index Continuous Cardiac Output) device is one such alternative, integrating a wide array of both static and dynamic haemodynamic data through a combination of trans-cardiopulmonary thermodilution and pulse contour analysis. The requirement for intra-arterial and central venous catheterisation limits the use of PiCCO to those with evolving critical illness or at high risk of complex and severe haemodynamic derangement. While the accuracy of trans-cardiopulmonary thermodilution as a measure of cardiac output is well established, several other PiCCO measurements require further validation within the context of their intended clinical use. As with all advanced haemodynamic monitoring systems, efficacy in improving patient-centred outcomes has yet to be conclusively demonstrated. The challenge with PiCCO is in improving the understanding of the many variables that can be measured and integrating those that are clinically relevant and adequately validated with appropriate therapeutic interventions.