Changes In Cardiac Index Research Articles

Metabolic Alterations in Myocardial Metabolism during Ex Situ Heart Perfusion

Purpose Ex situ heart perfusion (ESHP) is a novel method for preservation of the donated heart in a semi-physiologic state and provides the opportunity to evaluate pre-transplant function. Because of the well-described extraordinary metabolic requirements of the heart, efficient metabolic support is critical for optimal preservation of function and viability. Our aim was to determine changes in energy metabolism/energy substrates during extended ex situ perfusion of hearts in two different perfusion modes, working mode (WM) and non-working mode (NWM). Methods 17 female domestic breed pigs (37-47 kg) were included. Hearts were perfused on a custom ESHP apparatus (12 hours, NWM n=6 and WM n=7) with insulin and glucose infusions for metabolic support. Cardiac function, and changes in myocardial oxidative metabolism, glucose utilization, lactate, free fatty acids (FFA) and triglycerides (TG) were evaluated during ESHP. The enzymatic activity of pyruvate kinase was assessed using immunoassay techniques. The results were compared with baseline values (in vivo, n=4). Results Cardiac function declined over time but it was better preserved in WM (cardiac index change, p=0.02). Glucose utilization increased overtime in both groups (WM p=0.04, NWM p=0.04). Venous and arteriovenous lactate did not change over time and were not different between WM and NWM. FFA concentrations declined considerably during ESHP in both groups (WM p Conclusion Our data suggests functional decline during ESHP has a metabolic basis and is therefore reversible. Furthermore, a strategy of insulin and glucose appears insufficient for maintenance of metabolic integrity during ESHP and there is decoupling of glycolysis and the TCA cycle at the level of pyruvate kinase. Further research is required to determine the causative factors underpinning these alterations and optimal methods to abrogate their effects to ensure optimal preservation of contractile function during ESHP.

Esophageal Doppler Can Predict Fluid Responsiveness Through End-Expiratory and End-Inspiratory Occlusion Tests.

To assess whether, in patients under mechanical ventilation, fluid responsiveness is predicted by the effects of short respiratory holds on cardiac index estimated by esophageal Doppler. Prospective, monocentric study. Medical ICU. Twenty-eight adult patients with acute circulatory failure and a decision of the clinicians in charge to administer fluids. Before and after infusing 500 mL of saline, we measured cardiac index estimated by esophageal Doppler before and during the last 5 seconds of successive 15-second end-inspiratory occlusion and end-expiratory occlusion, separated by 1 minute. Patients in whom volume expansion increased cardiac index measured by transpulmonary thermodilution greater than or equal to 15% were defined as "fluid responders." Cardiac index measured by the Pulse Contour Cardiac Output device (from pulse contour analysis or transpulmonary thermodilution) was used as the reference. End-expiratory occlusion increased cardiac index estimated by esophageal Doppler more in responders than in nonresponders (8% ± 2% vs 3% ± 1%, respectively; p < 0.0001) and end-inspiratory occlusion decreased cardiac index estimated by esophageal Doppler more in responders than in nonresponders (-8% ± 5% vs -4% ± 2%, respectively; p = 0.0002). Fluid responsiveness was predicted by the end-expiratory occlusion induced percent change in cardiac index estimated by esophageal Doppler with an area under the receiver operating characteristic curve of 1.00 (95% CI, 0.88-1.00) and a threshold value of 4% increase in cardiac index estimated by esophageal Doppler. It was predicted by the sum of absolute values of percent changes in cardiac index estimated by esophageal Doppler during both occlusions with a similar area under the receiver operating characteristic curve (0.99 [0.86-1.00]) and with a threshold of 9% change in cardiac index estimated by esophageal Doppler, which is compatible with the esophageal Doppler precision. If the absolute sum of the percent change in cardiac index estimated by esophageal Doppler induced by two successive end-inspiratory occlusion and end-expiratory occlusion maneuvers is greater than 9%, it is likely that a 500 mL fluid infusion will increase cardiac output. This diagnostic threshold is higher than if only end-expiratory occlusion induced percent changes in cardiac index estimated by esophageal Doppler are taken into account.

Minimal Change in Cardiac Index With Increasing PEEP in Pediatric Acute Respiratory Distress Syndrome

Objective: To determine if increasing positive end expiratory pressure (PEEP) leads to a change in cardiac index in children with Pediatric Acute Respiratory Distress Syndrome ranging from mild to severe.Design: Prospective interventional study.Setting: Multidisciplinary Pediatric Intensive Care Unit in a University teaching hospital.Patients: Fifteen intubated children (5 females, 10 males) with a median age of 72 months (IQR 11, 132) and a median weight of 19.3 kg (IQR 7.5, 53.6) with a severity of Pediatric Acute Respiratory Distress Syndrome that ranged from mild to severe with a median lung injury score of 2.3 (IQR 2.0, 2.7).Measurements: Cardiac index (CI) and stroke volume (SV) were measured on baseline ventilator settings and subsequently with a PEEP 4 cmH2O higher than baseline. Change in CI and SV from baseline values was evaluated using Wilcoxon signed rank test.Results: A total of 19 paired measurements obtained. The median baseline PEEP was 8 cmH2O (IQR 8, 10) Range 6–14 cmH2O. There was no significant change in cardiac index or stroke volume with change in PEEP. Baseline median CI 4.4 L/min/m2 (IQR 3.4, 4.8) and PEEP 4 higher median CI of 4.3 L/min/m2 (IQR 3.6, 4.8), p = 0.65. Baseline median SV 26 ml (IQR 13, 44) and at PEEP 4 higher median SV 34 ml (IQR 12, 44) p = 0.63.Conclusion: There is no significant change in cardiac index or stroke volume with increasing PEEP by 4 cmH2O in a population of children with mild to severe PARDS.Clinical Trial Registration: The study is registered on Clinical trails.gov under the Identifier: NCT02354365.

Linggui Zhugan Decoction (苓桂术甘汤) Inhibits Ventricular Remodeling after Acute Myocardial Infarction in Rats by Suppressing TGF-β1/Smad Signaling Pathway

To investigate the inhibitory effect of Linggui Zhugan Decoction (LZD, ) on the ventricular remodeling (VR) after acute myocardial infarction (AMI) and related mRNA and proteins expression in transforming growth factor-beta 1 (TGF-β1)/Smad signaling pathway, and explain its putative mechanism. A VR model was generated by ligation of coronary artery in mice. Two weeks after surgery, 60 mice were randomly divided into the model group, the sham-operation group (distilled water), the positive control group (2.4 mg/kg simvastatin), and the low-, medium- and high-dose LZD groups (2.1, 4.2, 8.4 g crude drug/kg, respectively) by a random number table, 10 mice in each group. Mice in each group was treated for 4 weeks. Changes of hemodynamics indices and cardiac weight index were detected by the PowerLab data acquisition and analysis recording instrument. Morphology changes of myocardial tissue were observed by hematoxylin-eosin and Masson staining. The expressions of TGF-β1, Smad2, Smad3, p-Smad2 and p-Smad3 in myocardial tissue were detected by Western blotting. The mRNA expressions of TGF-β1, Smad2 and Smad3 were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The expressions of matrix metalloprotein 2 (MMP2), MMP9, collagen I and collagen III were observed by immunohistochemical methods. VR mice showed significant dysfunction in hemodynamic indices and cardiac structure and function. Compared with the shamoperation group, myocardial tissue damage, interstitial fibrosis occurred in the model mice, left ventricular systolic pressure (LVSP), left ventricular pressure maximum contraction rate (+dp/dtmax) and left ventricular pressure maximum relaxation rate (-dp/dtmax) decreased significantly (all P<0.01), while left ventricular end-diastolic pressure (LVEDP), cardiac weight index and left ventricular weight index elevated significantly, meanwhile TGF-β1, p-Smad2, p-Smad3, Smad2, Smad3, MMP2, MMP9, collagen I, collagen III protein expressions in myocardial tissue and TGF-β1, Smad2 and Smad3 mRNA expressions increased significantly (all P<0.01). Compared with the model group, LZD could significantly improve the pathological changes of myocardial tissue, increase LVSP, +dp/dtmax and -dp/dtmax, lower LVEDP, reduce the whole heart weight index and left ventricular weight index and inhibit the over-expressions of TGF-β1, p-Smad2, p-Smad3, Smad2, Smad3, MMP2, MMP9, collagen I and collagen III proteins in myocardial tissue and mRNA expressions of TGF-β1, Smad2 and Smad3 (P<0.05 or P<0.01). LZD can significantly suppress VR induced by AMI, and its underlying mechanism may be associated with its inhibitory effect on the TGF-β1/Smad signaling pathway.

Haemodynamic Tolerance of Cardiac Surgical Patients Receiving Vasoactive Therapy in Upright Positioning

Introduction: There is a lack of consensus regarding when it is safe to commence exercise with cardiac surgical patients in the Intensive Care Unit (ICU) receiving vasoactive therapy. Patients receiving vasoactive therapy may therefore be subject to unnecessary bed rest. Objectives: The aims were to measure the effect of exercise in upright positioning on haemodynamic parameters of cardiac surgical patients receiving vasoactive therapy, to clarify what level of vasoactive medication may allow safe exercise, and determine the incidence of adverse events. Methods: This was a prospective, single-centre, cohort study conducted in the ICU of a cardiothoracic tertiary, university-affiliated hospital in Australia. Eligible participants were recruited from August 2017 to May 2018. The Flotrac-Vigileo system was utilized to obtain haemodynamic measurements. Subjects were progressively positioned from supine, standing and marching on spot and returned to supine. A between-within repeated measures ANOVA was conducted to compare haemodynamic variables over various positions and interactions with positions and dose of low vs medium to high levels of vasoactive medication. Results: 20 participants; 16 (80%) male; mean age of 65.9 (10.6) years; were studied, with 6 (30%) receiving low dose vasoactive medication and 14 (70%) receiving a moderate to high dose. There were significant increases in mean arterial pressure (MAP) (p = 0.018), heart rate (HR) (p = 0.050) and respiratory rate (RR) (p = 0.049) with upright positioning. There was no significant interaction between position and dose. There were no significant changes in cardiac output, stroke volume or cardiac index during upright positioning. One minor adverse event occurred in a participant on low dose Dopamine. This was a transient decrease in MAP. Conclusions: Exercise caused an increase in MAP, HR and RR, and led to no significant increases in other hemodynamic parameters. Our findings suggest that vasoactive therapy alone should not be considered a contraindication to exercise post-cardiac surgery.

Hemodynamic effects of extended prone position sessions in ARDS

BackgroundHemodynamic response to prone position (PP) has never been studied in a large series of patients with acute respiratory distress syndrome (ARDS). The primary aim of this study was to estimate the rate of PP sessions associated with cardiac index improvement. Secondary objective was to describe hemodynamic response to PP and during the shift from PP to supine position.MethodsThe study was a single-center retrospective observational study, performed on ARDS patients, undergoing at least one PP session under monitoring by transpulmonary thermodilution. PP sessions performed more than 10 days after ARDS onset, or with any missing cardiac index measurements before (T1), at the end (T3), and after the PP session (T4) were excluded. Changes in hemodynamic parameters during PP were tested after statistical adjustment for volume of fluid challenges, vasopressor and dobutamine dose at each time point to take into account therapeutic changes during PP sessions.ResultsIn total, 107 patients fulfilled the inclusion criteria, totalizing 197 PP sessions. Changes in cardiac index between T1 and T2 (early response to PP) and between T1 and T3 (late response to PP) were significantly correlated (R2 = 0.42, p < 0.001) with a concordance rate amounting to 85%. Cardiac index increased significantly between T1 and T3 in 49 sessions (25% [95% confidence interval (CI95%) 18–32%]), decreased significantly in 46 (23% [CI95% 16–31%]), and remained stable in 102 (52% [CI95% 45–59%]). Global end-diastolic volume index (GEDVI) increased slightly but significantly from 719 ± 193 mL m−2 at T1 to 757 ± 209 mL m−2 at T3 and returned to baseline values at T4. Cardiac index and oxygen delivery decreased slightly but significantly from T3 to T4, without detectable increase in lactate level. Patients who increased their cardiac index during PP had significantly lower CI, GEDVI, global ejection fraction at T1, and received significantly more fluids than patients who did not.ConclusionPP is associated with an increase in cardiac index in 18% to 32% of all PP sessions and a sustained increase in GEDVI reversible after return to supine position. Return from prone to supine position is associated with a slight hemodynamic impairment.

PO-286 The research about the evaluation index on cardiac reserve of female athletes

PO-286 The research about the evaluation index on cardiac reserve of female athletes

General laryngeal mask airway anesthesia with lumbar plexus and sciatic block provides better outcomes than general anesthesia and endotracheal intubation in elderly patients undergoing hip surgery

ObjectiveTo compare the perioperative outcomes and hemodynamic effects at induction of general laryngeal mask airway (LMA) anesthesia with lumbar plexus-sciatic nerve block (LPSB) and general anesthesia with endotracheal intubation (ET) in elderly patients undergoing hip surgery. MethodsA total of 63 patients having open reduction internal fixation of an intertrochanteric fracture were randomly assigned to receive LMA anesthesia with LPSB or general anesthesia with ET. Perioperative and postoperative outcomes were compared between the 2 groups. ResultsCompared with the LMA/block group, there were significant reductions in systolic blood pressure, diastolic blood pressure, and mean arterial pressure at induction in the general endotracheal group (all, P < 0.001). In the general ET group, 84% of the patients experienced at least one episode of significant hypotension, whereas no patient in the LMA/block group had significant hypotension (P < 0.001). There were no changes in cardiac output, cardiac index, stroke volume, and stroke volume index of the LMA/block group, whereas significant changes were noted in the general anesthesia ET group. Significantly fewer complications were noted in the LMA/block group, and LMA block was associated with shorter weaning time, fewer returns to the intensive care unit, and less postoperative pain. ConclusionsGeneral LMA anesthesia with LPSB provides better outcomes that general ET anesthesia in elderly patients undergoing hip surgery.

Cardiac Index Changes With Fluid Bolus Therapy in Children With Sepsis-An Observational Study.

Fluid bolus therapy is the initial recommended treatment for acute circulatory failure in sepsis, yet it is unknown whether this has the intended effect of increasing cardiac index. We aimed to describe the effect of fluid bolus therapy on cardiac index in children with sepsis. A prospective observational cohort study. The Emergency Department of The Royal Children's Hospital, Melbourne, VIC, Australia. A convenience sample of children meeting international consensus criteria for sepsis with acute circulatory failure. Treating clinician decision to administer fluid bolus therapy. Transthoracic echocardiography was recorded immediately before, 5 minutes after, and 60 minutes after fluid bolus therapy. Cardiac index was calculated by a pediatric cardiologist blinded to the timing of the echocardiogram. Cardiac index was calculated for 49 fluid boluses in 41 children. The median change in cardiac index 5 minutes after a fluid bolus therapy was +18.0% (interquartile range, 8.6-28.1%) and after 60 minutes was -6.0% (interquartile range, -15.2% to 3.0%) relative to baseline. Thirty-one of 49 fluid boluses (63%) resulted in an increase in cardiac index of greater than 10% at 5 minutes, and these participants were considered fluid responsive. This was sustained in four of 31 (14%) at 60 minutes. No association between change in cardiac index at 5 or 60 minutes and age, baseline mean arterial blood pressure, fluid bolus volume, and prior volume of fluid bolus therapy was found on linear regression. Fluid bolus therapy for pediatric sepsis is associated with a transient increase in cardiac index. Fluid responsiveness is variable and, when present, not sustained. The efficacy of fluid bolus therapy for achieving a sustained increase in cardiac index in children with sepsis is limited.

Abstract P-252: TRANSFUSION RESPONSE PREDICTION BY INTEGRATED MEASURE OF OXYGEN DELIVERY (IDO2 INDEX)

Aims & Objectives: Red blood cell (RBC) transfusion is indicated to improve O2 delivery, or to relieve stress imposed by compensated anemia. Benefit anticipated from improving O2 carrying capacity must be balanced against (other) adverse influences of transfusion. We lack tools that: 1) differentiate between patients who require transfusions and those that do not and 2) guide transfusion timing and amount based upon O2 delivery targets. Here, we evaluate utility of an integrated physiologic measure of O2 delivery insufficiency (iDO2) in predicting transfusion response. Methods We studied 3 PICU groups receiving blood; a prospective group and 2 retrospective groups with cardiac output monitoring during transfusion. We evaluated demographics, hemodynamics, Hb, measured oxygen delivery (mDO2) and iDO2, a risk analytic for inadequate O2 delivery computed from multiple physiologic and laboratory data (lower value indicates more stable O2 delivery homeostasis). Results We identified 98 transfusion events, May 2013 to December 2016; 71 included cardiac output monitoring (Table 1). Hb increased post-transfusion (p<0.0001), as did mDO2 (p=0.0012) and systemic vascular resistance (p=0.0004), without change in cardiac index (p=0.97) (Figure 1). There was no relationship between pre-transfusion Hb, or Hb change, with any hemodynamic or measured O2 delivery parameter. Pre-transfusion iDO2 demonstrated inverse correlation with the change in iDO2 post-transfusion (p<0.0001) (pre-transfusion assessment of impaired integrated O2 delivery homeostasis, indicates post-transfusion benefit) (Figure 1). Conclusions Despite increasing O2 carrying capacity, RBC transfusions: (1) have variable impact on O2 delivery, (2) that is dependent on pre-transfusion status of O2 delivery homeostasis, assessment of which may add value to transfusion decision making.

Estimating the rapid haemodynamic effects of passive leg raising in critically ill patients using bioreactance

BackgroundRapid detection of changes in cardiac index (CI) in real time using minimally invasive monitors may be of clinical benefit. We tested whether the Starling-SV bioreactance device, which averages CI over a short 8 s period, could assess the effects of passive leg raising (PLR), a clinical test that is recommended to assess fluid responsiveness during septic shock. MethodsIn 32 critically ill patients, we measured CI by transpulmonary thermodilution (PiCCO2, CItd), pulse contour analysis (PiCCO2, CIPulse), and the Starling-SV device (CIStarling) at baseline. CIPulse and CIStarling were measured again at the end of a PLR test. In the 13 patients with a positive PLR test, CItd, CIPulse, and CIStarling were measured before and after a 500 ml saline infusion. The primary outcome was relative changes from baseline measurements in CItd, CIPulse, and CIStarling. Secondary outcomes compared absolute values measured by each method. ResultsRelative changes in CIPulse and CItd were significantly correlated (r=0.82; n=45; P<0.001), with an 89% concordance rate (n=45 paired measurements). Relative changes in CIStarling and CItd were also significantly correlated (r=0.59; n=45; P<0.001) with a 78% concordance rate. For absolute measures of CI (n=77 paired measurements), the bias between CIPulse and CItd was 0.01 L min−1 m−2 (limits of agreement, –0.49 and 0.51 L min−1 m−2; 15% percentage error). Bias between CIStarling and CItd was 0.03 L min−1 m−2 (limits of agreement, –1.61 and 1.67 L min−1 m−2; 48% percentage error). ConclusionsIn critically ill patients, a non-invasive bioreactance device with a shorter averaging period assessed a passive leg raising test with reasonable accuracy.

Acute Effect of Inhaled Iloprost in Children with Pulmonary Arterial Hypertension Associated with Simple Congenital Heart Defects.

Inhaled prostacyclin analogue iloprost is currently utilized in adult patients with pulmonary arterial hypertension (PAH), but little information is available on its use in the pediatric population. This study evaluated the safety and acute haemodynamic effects of inhaled iloprost in children with PAH associated with congenital heart disease (CHD). Children with PAH-CHD who underwent cardiac catheterization and iloprost administration in our catheter laboratory between June 2007 and October 2015 were included. Iloprost was administered by atomization inhalation and changes in hemodynamic parameters were recorded. In total, 100 children with PAH-CHD were enrolled. Median age was 13 [1.5-18.0] years and 34% were male. A ventricular septal defect was present in 84%, a patent duct in 12%, a complete atrioventricular septal defect in 2%, and an isolated atrial septal defect in 2%. Pulmonary vascular resistance indexed (PVRI) was above 8WUm2 in 96% and was above a third systemic (Rp/Rs > 0.33) in 97%. Iloprost was well tolerated in all patients. Following iloprost inhalation, mean pulmonary arterial pressure decreased from 78.4 ± 9.2 to 72.8 ± 10.8mmHg (p < 0.01) and pulmonary-to-systemic blood flow ratio (Qp/Qs) increased from 1.12 ± 0.48 to 1.37 ± 0.63 (p < 0.01), with no change in cardiac index (Qs). PVRI decreased from 21.0 ± 9.0 to 16.9 ± 8.0WUm2 (p < 0.01) following inhalation but 92% patients still had a PVRI > 8WUm2 and 93% an Rp/Rs > 0.33. Acute inhalation of iloprost in children with PAH associated with CHD resulted in a significant improvement in hemodynamic parameters. Despite this, few patients achieve strict criteria of operability, underscoring the importance of early screening and timely repair of CHD.

A Bayesian network meta-analysis on the efficacy and safety of eighteen targeted drugs or drug combinations for pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) can be relieved by pharmacological interventions, especially the targeted drug, which is classified into endothelin receptor antagonist, phosphodiesterase 5 inhibitor, prostaglandin I2, soluble guanylate cyclase stimulator and selective non-prostanoid prostacyclin receptor agonist. To solve the contradictions existing in reported trials and provide a comprehensive guideline for clinical practice. PubMed, Embase, Cochrane library, and clinicaltrials.gov were searched. The basic information about the article, trial, arm, intervention, and the detailed data of outcome, including 6 minutes walking distance (6MWD) change, WHO functional class (FC) improvement, Borg dyspnea score (BDS) change, cardiac index (CI) change, mean pulmonary arterial pressure (mPAP) change, mean right arterial pressure (mRAP) change, pulmonary vascular resistance (PVR) change, clinical worsening, hospitalization, death, severe adverse events (SAEs), and withdrawal were extracted. The rank of treatments was estimated. 10,230 cases provided the firsthand comparison data about targeted drugs for treating PAH. For 6MWD, ambrisentan + tadalafil, vardenafil, and sildenafil + bosentan were better than others. Epoprostenol, macitentan, and sildenafil represented a greater WHO FC improvement. Vardenafil and treprostinil were better for BDS. So were bosentan + epoprostenol and bosentan alone for CI. Iloprost plus bosentan, bosentan + epoprostenol, and epoprostenol were better for mPAP. Iloprost plus bosentan, bosentan alone, and selexipag could reduce PVR. Sildenafil, epoprostenol, and vardenafil had the highest probability to reduce the incidence of death and withdrawal. To conclude, vardenafil and iloprost + bosentan showed relatively better performance in both efficacy and safety. However, the therapeutic choice should be made according to both the feature of each therapy and the individual condition.

Change in cardiac output during Trendelenburg maneuver is a reliable predictor of fluid responsiveness in patients with acute respiratory distress syndrome\xa0in the prone position under protective ventilation

BackgroundPredicting fluid responsiveness may help to avoid unnecessary fluid administration during acute respiratory distress syndrome (ARDS). The aim of this study was to evaluate the diagnostic performance of the following methods to predict fluid responsiveness in ARDS patients under protective ventilation in the prone position: cardiac index variation during a Trendelenburg maneuver, cardiac index variation during an end-expiratory occlusion test, and both pulse pressure variation and change in pulse pressure variation from baseline during a tidal volume challenge by increasing tidal volume (VT) to 8 ml.kg-1.MethodsThis study is a prospective single-center study, performed in a medical intensive care unit, on ARDS patients with acute circulatory failure in the prone position. Patients were studied at baseline, during a 1-min shift to the Trendelenburg position, during a 15-s end-expiratory occlusion, during a 1-min increase in VT to 8 ml.kg-1, and after fluid administration. Fluid responsiveness was deemed present if cardiac index assessed by transpulmonary thermodilution increased by at least 15% after fluid administration.ResultsThere were 33 patients included, among whom 14 (42%) exhibited cardiac arrhythmia at baseline and 15 (45%) were deemed fluid-responsive. The area under the receiver operating characteristic (ROC) curve of the pulse contour-derived cardiac index change during the Trendelenburg maneuver and the end-expiratory occlusion test were 0.90 (95% CI, 0.80–1.00) and 0.65 (95% CI, 0.46–0.84), respectively. An increase in cardiac index ≥ 8% during the Trendelenburg maneuver enabled diagnosis of fluid responsiveness with sensitivity of 87% (95% CI, 67–100), and specificity of 89% (95% CI, 72–100). The area under the ROC curve of pulse pressure variation and change in pulse pressure variation during the tidal volume challenge were 0.52 (95% CI, 0.24–0.80) and 0.59 (95% CI, 0.31–0.88), respectively.ConclusionsChange in cardiac index during a Trendelenburg maneuver is a reliable test to predict fluid responsiveness in ARDS patients in the prone position, while neither change in cardiac index during end-expiratory occlusion, nor pulse pressure variation during a VT challenge reached acceptable predictive performance to predict fluid responsiveness in this setting.Trial registrationClinicalTrials.gov, NCT01965574. Registered on 16 October 2013. The trial was registered 6 days after inclusion of the first patient.

Maternal cardiac output response to colloid preload and vasopressor therapy during spinal anaesthesia for caesarean section in patients with severe pre‐eclampsia: a randomised, controlled trial

We examined the haemodynamic effects of colloid preload, and phenylephrine and ephedrine administered for spinal hypotension, during caesarean section in 42 women with severe early onset pre-eclampsia. Twenty patients with pre-delivery spinal hypotension were randomly allocated to receive an initial dose of either 50 μg phenylephrine or 7.5 mg ephedrine; the primary outcome was percentage change in cardiac index. After a 300-ml colloid preload, mean (SD) cardiac index increased from 4.9 (1.1) to 5.6 (1.2) l.min-1 .m-2 (p < 0.01), resulting from an increase in both heart rate, from 81.3 (17.2) to 86.3 (16.5) beats.min-1 (p = 0.2), and stroke volume, from 111.8 (19.0) to 119.8 (17.9) ml (p = 0.049). Fourteen (33%) and 23 (54.8%) patients exhibited a stroke volume response > 10% and > 5%, respectively; a significant negative correlation was found between heart rate and stroke volume changes. Spinal hypotension in 20 patients was associated with an increase from baseline in cardiac index of 0.6 l.min-1 .m-2 (mean difference 11.5%; p < 0.0001). After a median [range] dose of 50 [50-150] μg phenylephrine or 15 [7.5-37.5] mg ephedrine, the percentage change in cardiac index during the measurement period of 150 s was greater, and negative, in patients receiving phenylephrine vs. ephedrine, at -12.0 (7.3)% vs. 2.6 (6.0)%, respectively (p = 0.0001). The percentage change in heart rate after vasopressor was higher in patients receiving phenylephrine, at -9.1 (3.4)% vs. 5.3 (12.6)% (p = 0.0027), as was the change in systemic vascular resistance, at 22.3 (7.5) vs. -1.9 (10.5)% (p < 0.0001). Phenylephrine effectively reverses spinal anaesthesia-induced haemodynamic changes in severe pre-eclampsia, if left ventricular systolic function is preserved.

Evaluation of the Clinical Utility of Transesophageal Echocardiography and Invasive Monitoring to Assess Right Ventricular Function During and After Pulmonary Endarterectomy

Patients undergoing pulmonary endarterectomy (PEA) have impaired right ventricular function. The authors sought to assess the clinical utility of commonly used perioperative echocardiographic and right heart catheter measurements in patients undergoing PEA. A single-center prospective observational study. The study was conducted in a quaternary care cardiac surgical center in the United Kingdom. Patients undergoing PEA between April 2015 and January 2016. Thermodilution cardiac index and echocardiography variables were measured at 3 time points: before sternotomy (T1), after pericardial incision (T2), and after sternal closure (T3). Six-month follow-up echocardiography and 6-minute walk (6-MWT) test were performed. Fifty patients were recruited and complete data sets were available for 41 patients. Tricuspid annular plane systolic excursion declined after pericardial incision and cardiopulmonary bypass (T1: 15 ± 4 mm, T2: 13 ± 4 mm, T3: 7 ± 2 mm; p < 0.0001), returning to baseline 6 months postoperatively. Cardiac index (T1: 2.5 ± 0.7 L/min/m2, T2: 2.6 ± 0.6 L/min/m2, T3: 2.3 ± 0.5 L/min/m2; p = 0.07) and right ventricular fractional area change (T1: 36 ± 11%, T2: 40 ± 12%, T3: 40 ± 9%; p = 0.12) were preserved perioperatively. 6-MWT improved from baseline (294 ± 111 m) to follow-up (357 ± 107 m) (p < 0.001). Pulmonary vascular resistance at T3 correlated moderately with follow-up 6-MWT (R = -0.60). In patients undergoing PEA, invasive measurements and echocardiography assessment of right ventricular function are not interchangeable. Tricuspid annular plane systolic excursion is not a reliable measure of right ventricular function perioperatively. Pulmonary vascular resistance shows moderate correlation with postoperative functional capacity.

PP.06.21] VOLUME-COMPRESSIVE OSCILLOMETRY IN NONINVASIVE ASSESSMENT OF HEMODYNAMIC PARAMETERS IN HYPERTENSIVE PATIENTS

Objective: To evaluate hemodynamic parameters in patients with arterial hypertension (AH) before and during antihypertensive treatment using volume-compressive oscillometry (VCO) - new cuff-based device. The main advantages of VCO comparing to other oscillometry technic of BP registration is formation and recording the curve automatically in synchronism with the cuff inflation and recording the artery response by changing the cuff volume throughout the all period of cuff compression. VCO diagram could considered as indicator of aortic stiffness. Design and method: 45 untreated patients hospitalized with AH without acute coronary syndrome, severe valve problems, secondary hypertension, advanced chronic heart failure were enrolled. Mean age 55 ± 11.8 yrs, 51% male, mean BMI - 28.9 ± 6.7 kg/m2. Antihypertensive treatment included combination of amlodipine 5 mg/fosinopril 10 mg per day. The pulse wave velocity (PWV), brachial blood pressure (BP), cardiac index, stroke index and systemic vascular resistance were measured twice (at admission and discharging) by VCO (EDTV, Russia). Results: The mean systolic BP by VCO at admission was 147.7 ± 14.8 mmHg (by Korotkoff method 161 ± 9.8 mm Hg), diastolic 83.1 ± 14.1 mmHg (by Korotkoff method 99 ± 11.3 mmHg) and mean pulse pressure 64 ± 9.5 mmHg. Mean heart rate was 70.4 ± 14.5 bpm. Mean cardiac index was 3.08 ± 0.44 l/(min*m2), stroke index - 45.7 ± 11.7 ml/m2 and systemic vascular resistance (SVR) was 1373 ± 236 dyn*s/cm5. Mean PWV in these population was 7.6 ± 1.1 m/sec. After treatment with mean duration of hospitalization 6.3 ± 2.5 days, systolic and diastolic BP by VCO were reduced to 123.3 ± 10.8 mmHg and 57.5 ± 13.3 mmHg respectively (p < 0.05). Mean pulse pressure increased to 65.9 ± 11.8 mm Hg nonsignificantly. Mean stroke index increased to 49.7 ± 16.7 ml/m2 and SVR decreased to 1169 ± 374 dyn*s/cm5. We found no significant changes in cardiac index, heart rate and PWV. Conclusions: Systolic and diastolic BP by VCO is significantly lower comparing to Korotkoff method. Next studies are needed to determine the feasibility of VCO in noninvasive assessment of central hemodynamics.

294 - Evaluating Hemodynamic Effects of Clevidipine in Cardiothoracic Surgery Patients with Reduced Ejection Fraction

Background: Clevidipine is an ultra-rapid acting intravenous dihydropyridine calcium channel blocker indicated for the reduction of blood pressure. It is particularly beneficial in the post-operative surgical setting due to its ability for rapid titration. However, there is limited data regarding the efficacy and hemodynamic effects of clevidipine in patients with heart failure with reduced ejection fraction (HFrEF). The primary objective of this study is to evaluate the hemodynamic effects of clevidipine in post-cardiothoracic surgery patients. Secondary objectives include evaluating the percentage of mean arterial pressure readings at goal, intensive care unit (ICU) and hospital length of stay, presence of arrhythmias, and rehospitalization and mortality within 1 year of follow up. Methods: This study was a single center, retrospective chart review of cardiothoracic surgery patients who received clevidipine between December 1, 2012 and November 30, 2016. Patients were included if they underwent cardiothoracic surgery excluding heart transplantation, had invasive hemodynamic monitoring, left ventricular ejection fraction of 40% or less, and were 18 years or older. Patients on extracorporeal membrane oxygenation or concomitant vasopressor or inotropic therapy, with the exception of milrinone and dobutamine, were excluded. Results: A total of 633 patients received clevidipine during the study period. Only 11 patients met all inclusion criteria. The mean clevidipine rate was 5.07 mg/hr with a mean length of infusion of 30.9 hours. The cardiac index increased from baseline to time of clevidipine discontinuation in 7 patients, but the mean change in cardiac index from baseline to time of clevidipine discontinuation was −0.036 L/min/m2. The mean pulmonary artery pressure trended down in most patients (72.7%) when compared at clevidipine initiation and discontinuation. All patients saw a reduction in their mean arterial pressure to a value of 90 mmHg or less within the first 6 hours of clevidipine administration. The mean ICU and hospital length of stay was 15.1 days and 22.3 days. There were 4 patients that developed an arrhythmia during the clevidipine infusion. Serum creatinine remained stable between 0.5 and 1.5 mg/dL in 8 of 11 patients. All patients survived to hospital discharge, with 63.6% of patients discharged to home and the remaining discharged to a rehab facility. No patients died within 1 year of discharge. Conclusions: The results of this study showed that the use of clevidipine in cardiothoracic surgery patients was associated with quick and effective blood pressure management. Patients did not have any sustained adverse effects thought to be contributed to the administration of clevidipine. The main limitation of this study was that concomitant medications may have impacted patient hemodynamic profile and outcomes. Future prospective studies are needed to assess the safety and efficacy of clevidipine in this population.

Hemodynamic Determinants of the Biologic Variation of N-Terminal Pro–B-Type Natriuretic Peptide in Patients With Stable Systolic Chronic Heart Failure

Background ContextBiologic variation of N-terminal pro–B-type natriuretic peptide (NT-proBNP) in chronic heart failure (CHF) may affect blood levels and risk stratification. The sources of NT-proBNP variation are unknown. Methods and ResultsWe performed NT-proBNP measurements and clinical and hemodynamic assessments in 50 patients with heart failure with reduced ejection fraction (HFrEF) who met criteria for clinical stability over 2 time intervals. Hemodynamic variables were measured with the use of inert gas rebreathing and impedance cardiography. Heart rhythm was monitored with the use of external electrocardiographic event recorders throughout the study. Determinants of NT-proBNP-levels and both absolute (ΔNT-proBNPabs) and relative (ΔNT-proBNP%) changes at 1-week and 2-week intervals were identified with the use of univariable and multivariable linear mixed-effects models and linear regression analyses, respectively.Clinical and hemodynamic variables did not significantly change between study visits. The individual variation of NT-proBNP at 2 weeks was 9.2% (range 3.9%–18.6%). Weight and glomerular filtration rate were independently associated with baseline NT-proBNP concentrations (P = .01 and P = .005, respectively). There was no relationship between absolute and relative changes of NT-proBNP at 1-week intervals and changes in clinical and hemodynamic variables. Absolute change of NT-proBNP at 2-week intervals was associated with absolute change in left cardiac work index (P = .008), and relative change in NT-proBNP at 2-week intervals was determined by relative change of thoracic fluid content index (P = .008) and diastolic blood pressure (P = .01). The coefficients of determination (R2) for the multivariable models with Δ1wkNT-proBNPabs, Δ2-weeksNT-proBNPabs, Δ1wkNT-proBNP%, and Δ2wksNT-proBNP% as dependent variables were 0.21, 0.19, 0.10, and 0.32, respectively. ConclusionsIn patients with stable HFrEF, changes in clinical and hemodynamic variables only marginally contribute to the variation of NT-proBNP.

Outcome of intraoperative goal-directed therapy using Vigileo/FloTrac in high-risk patients scheduled for major abdominal surgeries: A prospective randomized trial

BackgroundThis study evaluated impact of intraoperative goal-directed therapy (GDT) judged by changes of stroke volume variation (SVV) and cardiac index (CI) using the Vigileo/FloTrac system on postoperative (PO) morbidities and mortality rates in high risk patients scheduled for major abdominal surgeries in comparison to conventional fluid therapy (CT).Methods86 patients were randomly allocated into one of two equal groups: CT group = 43 patients received crystalloid solution and on demand bolus of 250 ml colloids with possible addition of vasopressor or inotrope to target MAP at 60–90 mmHg, CVP at 8–12 mmHg and urine output at >0.5 ml/kg/hr and GDT group = 43 patients received crystalloid fluid therapy (FT) and colloids (3 ml/kg) with possible addition of vasopressor or inotrope according to predefined protocol with a target CI 2.5 L/min/m2, SVV < 12% with MAP > 65 mmHg. Physiological and Operative Severity Score for Enumeration of Mortality and Morbidity (POSSUM) was used to predict morbidity and mortality rates. Study outcomes included ICU and total hospital morbidity and mortality rates and length of stay (LOS).ResultsIntraoperative GDT reduced ICU morbidity rate (16.3%) than the POSSUM predicted rate (39.78%) and significantly (p = 0.039) than CT group (37.2%), while in CT group ICU morbidity rate coincided with POSSUM predicted rate (42.86%). ICU and total hospital LOS were significantly shorter with GDT group than with CT group. However, mortality rates weren’t significantly lower with GDT group than CT group (7% vs. 11.6%). The applied protocol for intraoperative GDT reduced significantly crystalloid infusion and despite of significantly higher amount of received colloids, the total amount of FT was significantly less than CT group.ConclusionThe applied protocol for intraoperative GDT provided significant reduction of PO morbidities, ICU and hospital LOS but couldn‘t significantly reduce mortality rates in high risk patients scheduled for major abdominal surgeries.