Systemic Vascular Resistance Index Research Articles

Sex differences in acute hemodynamic response in comatose survivors of OHCA

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Novo Nordisk Fonden Background In critically ill patients with cardiogenic shock, neurohormonal activation is higher in females compared with males. Whether this is the case in patients resuscitated from out of hospital cardiac arrest (OHCA) is not known and whether sex-based differences relate to achieving mean-arterial-pressure (MAP)-target has not previously been described. Methods This was an investigator-initiated, randomized, controlled study of targeted MAP (63 vs 77 mmHg) and PaO2 (9-10 vs 13-14 kPa) interventions in 789 comatose OHCA (of presumed cardiac origin) patients. Patients underwent serial hemodynamic assessments with pulmonary artery catheter at time of insertion, 6 h, 12 h, 24 h, 36 h and 48 h. Among parameters recorded were heart rate (HR), cardiac output (CO) and central venous pressure (CVP), from which cardiac index (CI) and systemic vascular resistance index (SVRI) were derived. Patient characteristics included sex for stratification, age, time to return of spontaneous circulation (ROSC) and initial electrocardiographic (ECG) rhythm. Results Hemodynamic parameters from 729 patients were analysed, of which 138 (19%) were female and 591 (81%) were male. Both groups had a median age of 64 years, with median time-to-ROSC of 19 minutes in females versus 18 minutes in males. In females versus in males, SVRI and HR were higher (fig.1,2). There were no differences among sexes with regards to CI, MAP, or dose of noradrenaline. At 12 hours, median SVRI in females was 755 dyn·s/cm5·m2 (inter-quartile ratio, IQR 569-931) versus 554 dyn·s/cm5·m2 (IQR 441-684) in males (P<0.0001). At the same point in time, median HR was 71 beats/minute (bpm) in females (IQR 59-82) versus 62 bpm (IQR 54-74) in males (P<0.0001). Lastly, 12-hour median CI was 1.82 L/min/m2 (IQR 1.54-2.40) in females versus 1.95 L/min/m2 (IQR 1.63-2.43) in males (P=0.1303). Conclusions Female comatose OHCA patients had higher SVRI and HR during the first 48 hours of ICU admission, without difference in MAP or vasopressor requirement. Sex specific physiological mechanisms may be involved in maintaining vascular resistance.

0207 Acute Total Sleep Deprivation Adversely Impacts Cardiovascular Measures across Long-Duration Intervals

Abstract Introduction For the first time, we comprehensively investigated the effects of repeated exposures to baseline (BL), total sleep deprivation (TSD), and recovery (REC) phases at 2, 4, and 8 months on cardiovascular (CV) measures. Methods We conducted a five-day experiment twice (at months 2 and 4) in a 4-month study (N=6 healthy adults; 3 females), and a similar five-day experiment three times (at months 2, 4, and 8) in an 8-month study (N=5 healthy adults; 2 females). During these repeated experiments, CV measures were collected via echocardiography or blood pressure monitor [systolic and diastolic blood pressure (SBP and DBP)] at three assessment time points: 1) after two baseline 8h time in bed (TIB) nights (BL); 2) after a night of total sleep deprivation (TSD); and 3) after two recovery nights of 8-10h TIB (REC). CV measures were also collected once pre and post study. Seated stroke volume (SV), cardiac index (CI), left ventricular ejection time (LVET), SBP and DBP, systemic vascular resistance index (SVRI), and mean arterial pressure (MAP) were collected. Data did not significantly differ between the two studies and therefore were pooled together for analysis (N=11). Repeated measures ANOVA and post-hoc comparisons corrected for multiple testing examined CV measures across all time points. Results SV, CI, SVRI, LVET, and SBP, but not DBP or MAP, showed significant changes across time. SV increased with TSD compared to pre-study, BL, and post-study at month 2. CI increased with TSD compared to pre-study, BL, REC, and post-study at month 2. SVRI decreased with TSD compared to pre-study, BL, and REC at month 2 and LVET and SBP increased with TSD compared to BL at month 2. In the 8-month sample subset, SBP increased with TSD compared to BL at month 8. Conclusion TSD increased SV, CI, LVET, and SBP, and decreased SVRI, compared to BL at month 2. Notably, TSD also increased SBP compared to BL at month 8, indicating a sustained adverse effect after long-duration repeated exposure to TSD. Overall, SV, CI, SVRI, LVET, and SBP are reliable biomarkers for assessing the harmful long-term cardiovascular effects of TSD. Support (if any) NASA grants NNX14AN49G and 80NSSC20K0243 (NG)

Acute Effects of a Maximal Cardiopulmonary Exercise Test on Cardiac Hemodynamic and Cerebrovascular Response and Their Relationship with Cognitive Performance in Individuals with Type 2 Diabetes.

Cardiovascular and cerebrovascular diseases are prevalent in individuals with type 2 diabetes (T2D). Among people with T2D aged over 70 years, up to 45% might have cognitive dysfunction. Cardiorespiratory fitness (V˙O2max) correlates with cognitive performances in healthy younger and older adults, and individuals with cardiovascular diseases (CVD). The relationship between cognitive performances, V˙O2max, cardiac output and cerebral oxygenation/perfusion responses during exercise has not been studied in patients with T2D. Studying cardiac hemodynamics and cerebrovascular responses during a maximal cardiopulmonary exercise test (CPET) and during the recovery phase, as well as studying their relationship with cognitive performances could be useful to detect patients at greater risk of future cognitive impairment. Purposes: (1) to compare cerebral oxygenation/perfusion during a CPET and during its post-exercise period (recovery); (2) to compare cognitive performances in patients with T2D to those in healthy controls; and (3) to examine if V˙O2max, maximal cardiac output and cerebral oxygenation/perfusion are associated with cognitive function in individuals with T2D and healthy controls. Nineteen patients with T2D (61.9 ± 7 years old) and 22 healthy controls (HC) (61.8 ± 10 years old) were evaluated on the following: a CPET test with impedance cardiography and cerebral oxygenation/perfusion using a near-infrared spectroscopy. Prior to the CPET, the cognitive performance assessment was performed, targeting: short-term and working memory, processing speed, executive functions, and long-term verbal memory. Patients with T2D had lower V˙O2max values compared to HC (34.5 ± 5.6 vs. 46.4 ± 7.6 mL/kg fat free mass/min; p < 0.001). Compared to HC, patients with T2D showed lower maximal cardiac index (6.27 ± 2.09 vs. 8.70 ± 1.09 L/min/m2, p < 0.05) and higher values of systemic vascular resistance index (826.21 ± 308.21 vs. 583.35 ± 90.36 Dyn·s/cm5·m2) and systolic blood pressure at maximal exercise (204.94 ± 26.21 vs. 183.61 ± 19.09 mmHg, p = 0.005). Cerebral HHb during the 1st and 2nd min of recovery was significantly higher in HC compared to T2D (p < 0.05). Executive functions performance (Z score) was significantly lower in patients with T2D compared to HC (-0.18 ± 0.7 vs. -0.40 ± 0.60, p = 0.016). Processing speed, working and verbal memory performances were similar in both groups. Brain tHb during exercise and recovery (-0.50, -0.68, p < 0.05), and O2Hb during recovery (-0.68, p < 0.05) only negatively correlated with executive functions performance in patients with T2D (lower tHb values associated with longer response times, indicating a lower performance). In addition to reduced V˙O2max, cardiac index and elevated vascular resistance, patients with T2D showed reduced cerebral hemoglobin (O2Hb and HHb) during early recovery (0-2 min) after the CPET, and lower performances in executive functions compared to healthy controls. Cerebrovascular responses to the CPET and during the recovery phase could be a biological marker of cognitive impairment in T2D.

Comparison of Hemodynamic Effects of Dobutamine and Ephedrine Infusions in Isoflurane-Anesthetized Horses.

The objective of this study was to compare the hemodynamic effects of dobutamine and ephedrine during the management of anesthesia-related hypotension in healthy horses. Thirteen horses underwent general anesthesia with isoflurane and were randomly divided into two different groups, one of which received a dobutamine constant rate infusion (CRI) (1 µg/kg bwt/min) and the other received an ephedrine CRI (20 µg/kg bwt/min) when hypotension (<60 mmHg) was identified, following up to 15 min after the blood pressure reached 70 mmHg. All horses were equipped with a pulmonary artery catheter and a peripheral artery catheter, and multiparameter monitoring commenced as soon as they were under mechanical ventilation. Hemodynamic parameters were recorded, while tissue perfusion markers (peripheral oxygen saturation, arterial oxygen partial pressure, arterial carbon dioxide partial pressure, arterial pH, arterial plasma bicarbonate concentration, arterial oxygen saturation, mixed venous oxygen saturation, mixed venous oxygen content, arterial oxygen content, arteriovenous oxygen difference, oxygen delivery index, oxygen consumption index, and oxygen extraction ratio), serum lactate concentration, and troponin I concentrations were analyzed before the start of infusions (T0), when the blood pressure reached 70 mmHg (T1), and 15 min after T1 (T2). The time to restore the arterial pressure was similar in both groups (p > 0.05); however, the heart rate was higher in the ephedrine group (p = 0.0098), and sinus bradyarrhythmia occurred in the dobutamine group. Furthermore, both experimental protocols increased cardiac output (p = 0.0012), cardiac index (p = 0.0013), systemic vascular resistance (p = 0.008), systemic vascular resistance index (p < 0.001), and ameliorated perfusion markers. In the dobutamine group, the pulmonary artery wedge pressure (p < 0.001) and systolic index (p = 0.003) were elevated, while the arteriovenous oxygen difference was reduced in the ephedrine group (p = 0.02). Troponin I was used as a myocardial injury indicator, and did not differ between moments or between groups (p > 0.05). We concluded that both drugs were effective and safe to treat anesthetic hypotension under the conditions of this study.

Maximum Dose of Plain Epinephrine in Plastic Surgery: Room to Explore.

Epinephrine mixed with local anesthetics such as lidocaine or bupivacaine is routinely used in plastic surgery to increase the maximum safe dosage of local anesthesia and reduce blood loss through vasoconstriction. The pharmacokinetics of these epinephrine-local anesthetic combinations has been well studied, leading to well-established guidelines for maximum local anesthetic doses.1 However, local anesthetics have an associated toxicity risk and prevent impulse transmission/stimulation of motor nerves, which is particularly relevant in peripheral nerve surgery. As an alternative, plain epinephrine may be used to decrease blood loss and minimize blood within the surgical site. For this reason, it is commonly used in a wide range of plastic surgery procedures, including peripheral nerve surgery, body contouring procedures, cosmetic procedures performed under local anesthesia, and pediatric craniofacial surgery. In this Viewpoint, we examine the existing literature on the maximum dose of subcutaneous plain epinephrine and advocate for further research to guide the establishment of a maximum epinephrine dose. Within the literature, there have been reports of excessive epinephrine use causing systematic changes to patients’ physiology. These include increases in heart rate, cardiac index, and decreases in both mean arterial pressure and systemic vascular resistance index,2,3 which may be significant for patients with high-risk cardiovascular conditions. For this reason, plastic surgeons may act conservatively regarding maximum epinephrine dosing despite potential benefits with increased dosing. Additionally, studies of the vasoconstrictive effect of different epinephrine concentrations are almost exclusively conducted using epinephrine combined with local anesthetics.4 Kinsella et al have also identified this gap in the literature and studied the use of local epinephrine infiltration without local anesthetic in 102 palatoplasties, concluding that doses up to 10 μg/kg every 30 minutes did not lead to any cases of unstable tachycardia or hypertension.3 Similarly, Swan et al demonstrated no significant difference in heart rate, systolic blood pressure, or diastolic blood pressure in their high volume palatoplasty center when using 8 μm/kg of epinephrine mixed with 2 mg/kg of levobupivacaine.5 A recent review of the literature demonstrated that concentrations of epinephrine between 1:50,000 and 1:400,000 provide superior vasoconstrictive effects compared with dilute epinephrine concentrations.1 Given the frequency of use and potential benefit of plain epinephrine in a variety of surgical procedures, the lack of literature in this area warrants further investigation. The first step in addressing this gap is to establish a reference range by conducting a comprehensive review of clinical series in which epinephrine was used without hemodynamic complications. Next, small and large animal models should be used to establish preliminary dosing guidelines before human trials. Although basic science and clinical trials of this caliber would be logistically challenging and have significant associated costs, the authors believe that this gap in knowledge is worth highlighting for plastic surgeons, researchers, and trainees. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article.

Difference in outcomes of pediatric septic shock after fluid resuscitation according to the Ultrasound-guided Fluid Resuscitation (USFR) and American College of Critical Care Medicine (ACCM) protocols: A randomized clinical trial

Background Sepsis is a major cause of morbidity and mortality in children. The American College of Critical Care Medicine (ACCM) protocol currently in use in the management of septic shock carries a risk of fluid overload. With the use of ultrasonographic monitoring, the Ultrasound-guided Fluid Resuscitation (USFR) protocol may reduce the incidence of fluid overload and mortality.&#x0D; Objective To assess the difference in outcomes of fluid resuscitation in pediatric septic shock using the USFR vs. ACCM protocols.&#x0D; Methods This randomized clinical trial involved 36 subjects randomized equally into the USFR and ACCM groups. After randomization, each subject was given fluid resuscitation starting at 20 mL/kg and repeated every 5-10 minutes as needed, according to the ACCM protocol. After fluid resuscitation was given, patients in the ACCM group were evaluated for clinical signs, liver span, and rhonchi, whereas those in the USFR group underwent USCOM examination for cardiac index (CI), stroke volume index (SVI), and systemic vascular resistance index (SVRI). After 60 minutes, subjects in both groups were re-assessed for clinical signs, USCOM, pulmonary edema using lung ultrasound score (LUS), and liver span. Subjects were blinded as to the protocol they received. We compared 24-hour and 72-hour mortality rates, clinical improvement of shock at 60 minutes, cardiac index (CI), stroke volume index (SVI), and systemic vascular resistance index (SVRI), as well as pulmonary edema and hepatomegaly, between the two groups.&#x0D; Results At 60 minutes after resuscitation, there were significant differences between the ACCM and USFR groups in the proportion of clinical improvement (0/18 vs. 5/18, P=0.016), pulmonary edema (15/18 vs. 4/18, P&lt;0.001), and hepatomegaly (16/18 vs. 5/18, P&lt;0.001). Mortality rates at 24 hours and 72 hours in the ACCM vs. USFR groups were 17% vs. 12% (P=0.199) and 78% vs. 39% (P=0.009), respectively.&#x0D; Conclusion The USFR protocol reduces the occurrence of fluid overload and leads to a lower mortality rate at 72 hours compared to the ACCM fluid resuscitation protocol.

Accuracy of Cardiac Output Measured by Fourth-Generation FloTrac and LiDCOrapid, and Their Characteristics Regarding Systemic Vascular Resistance in Patients Undergoing Cardiac Surgery

The clinical use of less-invasive devices that calculate the cardiac output from arterial pressure waveform is increasing. The authors aimed to evaluate the accuracy and characteristics of the systemic vascular resistance index (SVRI) of the cardiac index measured by 2 less-invasive devices, fourth-generation FloTrac (CIFT) and LiDCOrapid (CILR), compared with the intermittent thermodilution technique, using a pulmonary artery catheter (CITD). This was a prospective observational study. This study was conducted at a single university hospital. Twenty-nine adult patients undergoing elective cardiac surgery. Elective cardiac surgery was used as an intervention. Hemodynamic parameters, CIFT, CILR, and CITD, were measured after the induction of general anesthesia, at the start of cardiopulmonary bypass, after completion of weaning from cardiopulmonary bypass, 30 minutes after weaning, and at sternal closure (135 measurements in total). The CIFT and CILR had moderate correlations with CITD (r=0.62 and 0.58, respectively). Compared with CITD, CIFT, and CILR had a bias of -0.73 and -0.61 L/min/m2, limit of agreement of -2.14-to-0.68 L/min/m2 and -2.42-to-1.20 L/min/m2, and percentage error of 39.9% and 51.2%, respectively. Subgroup analysis for evaluating SVRI characteristics showed that the percentage errors of CIFT and CILR were 33.9% and 54.5% in low SVRI (<1,200 dyne×s/cm5/m), 37.6% and 47.9% in moderate SVRI (1,200-1,800 dyne×s/cm5/m), 49.3% and 50.6% in high SVRI (>1,800 dyne·s/cm5/m2), respectively. The accuracy of CIFT or CILR was not clinically acceptable for cardiac surgery. Fourth-generation FloTrac was unreliable in high SVRI. LiDCOrapid was inaccurate across a broad range of SVRI, and minimally affected by SVRI.

Use of hemodynamic and laboratory monitoring tools to reduce the risk of mortality from pediatric septic shock

Background Early recognition of septic shock in terms of clinical, macrocirculatory hemodynamic, and microcirculatory laboratory parameters is a fundamental challenge in the emergency room and intensive care unit for early identification, adequate management, prevention of disease progression, and reduction of mortality risk.&#x0D; Objective To evaluate for possible correlations between survival outcomes of post-resuscitation pediatric septic shock patients and parameters of clinical signs, macrocirculatory hemodynamics, as well as microcirculatory laboratory findings.&#x0D; Methods This prospective, study was conducted in the PICU at Saiful Anwar Hospital, Malang, East Java. Inclusion criteria were children diagnosed with septic shock according to the 2005 Surviving Sepsis Campaign (SSC) criteria, aged &gt;30 days-18 years, who were followed up for 72h after resuscitation. The measured variables such as cardiac index (CI), systemic vascular resistance index (SVRI), stroke volume index (SVI) were obtained from ultrasonic cardiac output monitor (USCOM). Blood gas and lactate were obtained from laboratory findings. Heart rate, pulse strength, extremity temperature, mean arterial pressure (MAP), systolic blood pressure (SBP), capillary refill time (CRT), Glasgow coma scale (GCS), and diuretic used were obtained from hemodynamic monitoring tools. Survival outcomes of post-resuscitation pediatric septic shock patients were noted.&#x0D; Results There was a significant correlation between the outcomes of the pediatric septic shock patients 72h after fluid resuscitation and clinical, macrocirculatory hemodynamic, and microcirculatory laboratory parameters. After the 6th hour of observation, strong pulse was predictive of survival, with 88.2% area under the curve (AUC). At the 12th hour of observation, MAP &gt;50th percentile for age was predictive of survival, with 94% AUC.&#x0D; Conclusion For pediatric patients with septic shock, the treatment target in the first 6 hours is to improve strength of pulse, and that in the first 12 hours is to improve MAP &gt;50th percentile for age to limit mortality.

Adjunctive Hydrocortisone Improves Hemodynamics in Critically Ill Patients with Septic Shock: An Observational Study Using Transpulmonary Thermodilution.

Introduction: Septic shock is associated with high mortality and hemodynamic impairment. The use of corticoids is a common therapeutic tool in critically ill patients. However, data on the mechanisms and prognostic ability of hemodynamic improvement by adjunctive steroids are rare. This study primarily aimed to evaluate short-term effects of hydrocortisone therapy on catecholamine requirement and hemodynamics derived from transpulmonary thermodilution (TPTD) in 30 critically ill patients with septic shock and a 28 days mortality rate of 50%. Methods: Hydrocortisone was administered with an intravenous bolus of 200 mg, followed by a continuous infusion of 200 mg per 24 h. Hemodynamic assessment was performed immediately before as well as 2, 8, 16, and 24 h after the initiation of corticoids. For primary endpoint analysis, we evaluated the impact of hydrocortisone on vasopressor dependency index (VDI) and cardiac power index (CPI). Results: Adjunctive hydrocortisone induced significant decreases of VDI from 0.41 (0.29-0.49) mmHg-1 at baseline to 0.35 (0.25-0.46) after 2 h (P < .001), 0.24 (0.12-0.35) after 8 h (P < .001), 0.18 (0.09-0.24) after 16 h (P < .001) and 0.11 (0.06-0.20) mmHg-1 after 24 h (P < .001). In parallel, we found an improvement in CPI from 0.63 (0.50-0.83) W/m2 at baseline to 0.68 (0.54-0.85) after 2 h (P = .208), 0.71 (0.60-0.90) after 8 h (P = .033), 0.82 (0.6-0.98) after 16 h (P = .004) and 0.90 (0.67-1.07) W/m2 after 24 h (P < .001). Our analyses revealed a significant reduction in noradrenaline requirement in parallel with a moderate increase in mean arterial pressure, systemic vascular resistance index, and cardiac index. As a secondary endpoint, our results showed a significant decrease in lung water parameters. Moreover, changes in CPI (ΔCPI) and VDI (ΔVDI) after 24 h of hydrocortisone therapy revealed accurate prognostic ability to predict 28 days mortality (AUC = 0.802 vs 0.769). Conclusion: Adjunctive hydrocortisone leads to a rapid decrease in catecholamine requirement and a substantial circulatory improvement in critically ill patients with septic shock.

Fractional spinal anesthesia and systemic hemodynamics in frail elderly hip fracture patients

Background: Systemic haemodynamic effects of intrathecal anaesthesia in an aging and frail population has not been well investigated. We examined the systemic haemodynamics of fractional spinal anaesthesia following intermittent microdosing of a local anaesthetic and an opioid. Methods: We included 15 patients aged over 65 with significant comorbidities, planned for hip fracture repair. Patients received a spinal catheter and cardiac output monitoring using the LiDCOplus system. All measurements were performed prior to start of surgery. Invasive mean arterial pressure (MAP), cardiac index (CI), systemic vascular resistance index (SVRI), heart rate and stroke volume index (SVI) were registered. Two doses of bupivacaine 2.25 mg and fentanyl 15 µg were administered with 25-minute intervals. Hypotension was defined as a fall in MAP by &gt;30% or a MAP &lt;65 mmHg. Results: The incidence of hypotension was 30%. Hypotensive patients (n=5) were treated with low doses of norepinephrine (0.01-0.12 µg/kg/min). MAP showed a maximum reduction of 17% at 10 minutes following the first dose. CI, systemic vascular resistance index and stroke volume index decreased by 10%, 6%, and 7%, respectively, while heart rate was unchanged over time. After the second dose, none of the systemic haemodynamic variables were affected. Conclusions: Fractional spinal anaesthesia administered prior to surgery induced a minor to moderate fall in MAP, mainly caused by a reduction in cardiac output, induced by systemic venodilation, causing a fall in venous return. Our results are contrary to the widely held belief that hypotension is mainly the result of a reduction of systemic vascular resistance.

How Long Is Long Enough? Controlling for Acute Caffeine Intake in Cardiovascular Research.

Caffeine substantially affects cardiovascular functioning, yet wide variability exists in caffeine control procedures in cardiovascular reactivity research. This study was conducted in order to identify a minimal abstention duration in habitual coffee consumers whereby cardiovascular reactivity is unconfounded by caffeine; Six hours (caffeine's average half-life) was hypothesized. Thirty-nine subjects (mean age: 20.9; 20 women) completed a repeated measures study involving hand cold pressor (CP) and memory tasks. Caffeinated and decaffeinated coffee were administered. The following cardiovascular indices were acquired during pre-task, task, and post-task epochs prior to coffee intake, 30 min-, and six hours post-intake: Heart rate (HR), high-frequency heart rate variability (HF-HRV), root mean squared successive differences (RMSSD), systolic and diastolic blood pressures (SBP, DBP), mean arterial pressure (MAP), pre-ejection period (PEP), left ventricular ejection time (LVET), systemic vascular resistance (SVR), systemic vascular resistance index (SVRI). Results support the adequacy of a six-hour abstention in controlling for caffeine-elicited cardiovascular changes. The current study offers a suggested guideline for caffeine abstention duration in cardiovascular research in psychophysiology. Consistent practice in caffeine abstention protocols would promote validity and reliability across such studies.

Clinical Effects of Sacubitril/Valsartan Combined with Dapagliflozin in Patients with Diabetes and ST-segment Elevation Myocardial Infarction

Objectives: This study was aimed at observing the clinical effects of sacubitril/valsartan combined with dapagliflozin on cardiac function and ventricular remodeling in patients with type 2 diabetes and ST-segment elevation myocardial infarction (STEMI). Methods: Between May 2019 and May 2022, we retrospectively analyzed 57 patients with diabetes and STEMI receiving percutaneous coronary intervention: 32 patients receiving sacubitril/valsartan and dapagliflozin tablets comprised the observation group and 25 patients receiving angiotensin converting enzyme inhibition (ACEI) or angiotensin receptor blockers ARB) in combination with other hypoglycemic drugs comprised the control group. We compared the left ventricular end diastolic diameter (LVEDD), right ventricular end diastolic diameter (RVEDD), left ventricular ejection fraction (LVEF), N-terminal pro-B-type natriuretic peptide (NT-pro BNP), and noninvasive hemodynamic parameters at baseline and 3–6 months after treatment between the groups. Results: Before treatment, the parameters were similar between the observation group and control group. However, after 3−6 months of treatment, serum NT-pro BNP levels showed a greater decline in the observation group than the control group. Moreover, the LVEDD and LVEF improved more substantially in the observation group than the control group (P&lt;0.05). RVEDD did not markedly change after treatment (P&gt;0.05). After treatment, in the observation group, the cardiac index (CI) and cardiac output (CO) were significantly higher, and the thoracic fluid conduction (TFC) and systemic vascular resistance index (SVRI) were significantly lower, than those in the control group (P&lt;0.05). Conclusions: Sacubitril/valsartan combination with dapagliflozin exerted better effects than ACEI or ARB with other hypoglycemic drugs in improving cardiac function and ventricular remodeling in patients with diabetes and STEMI.

Effects of General Anesthesia on the Results of Cardiac Catheterization in Pediatric Patients with Ventricular Septal Defect

<b>Background:</b> There is no gold standard sedation method for pediatric cardiac catheterization. In congenital heart diseases with intracardiac shunts, hemodynamic parameters are prone to change depending on the ventilation conditions and anesthetics, although few studies have examined these effects. The purpose of this study was to investigate the effects of two different sedation methods on the hemodynamic parameters. <b>Methods:</b> This study retrospectively evaluated consecutive patients with ventricular septal defect (VSD) below 1 year of age who underwent cardiac catheterization at Aichi Children’s Health and Medical Center, who were divided into age- and VSD diameter-matched general anesthesia (GA) and monitored anesthesia care (MAC) under the natural airway groups (<i></i>n = 40 each), for comparison of hemodynamic parameters. <b>Results:</b> In the GA group, arterial blood pH and arterial partial pressure of oxygen were significantly higher (<i>p</i> < 0.01), whereas arterial partial pressure of carbon dioxide was significantly lower than in the MAC group (<i>p</i> < 0.01). Mean pulmonary artery pressure (<i>p</i> < 0.05) and systemic blood pressure (<i>p</i> < 0.01) were lower in the GA group. Pulmonary vascular resistance index (<i>p</i> < 0.01) and systemic vascular resistance index (<i>p</i> < 0.01) were also significantly lower in the GA group than the MAC group. There were no significant differences in pulmonary blood flow index, systemic blood flow index, and pulmonary/systemic blood flow ratio between the two groups. <b>Conclusions:</b> Cardiac catheterization under GA in VSD patients results in different hemodynamic parameters compared to that under MAC. In particular, when using pulmonary artery pressure and pulmonary vascular resistance measured under GA for judgment regarding the surgical indications or perioperative management, consideration should be given to the fact that these parameters might be lower compared to those measured under MAC.

Cardiovascular Function during First 24 Hours after Off-Pump and On-Pump CABG—A Prospective Observational Comparative Study

Purpose: Myocardial revascularization by coronary artery bypass grafting (CABG) in ischemic heart disease patients has direct impact on hemodynamic parameters in the immediate post-operative period. The peri-operative cardiovascular functioning is an important determinant for outcome of surgery. In On-Pump CABG (ONCAB), the cardiopulmonary bypass has a negative effect on myocardium. Off-Pump CABG (OPCAB) avoids the effect of CPB but complete revascularization with difficult positioning of heart is technically demanding. This study is aimed to compare the cardiovascular functioning in the immediate post-operative period after OPCAB and ONCAB. Methods: Total 106 patients were operated for CABG from January 2015 to June 2016, of which 75 patients were operated for OPCAB and 31 patients were operated for ONCAB. For the comparison, hemodynamic parameters were measured during anesthesia before surgery, postoperatively after 1 and 4 hours (h) in the ICU, and in the morning after surgery, approximately after 20 h. Results: The time-dependent rise of hemodynamic parameters like Cardiac Output (CO), Cardiac Index (CI), Stroke volume (SV) and Left Ventricular Stroke Work Index (LVSWI) in the immediate post-operative hours (1 h and 4 h) are more predominant in OPCAB group than ONCAB group although the difference is eliminated mostly at 20 h. The better peripheral vasodilation after OPCAB causes immediate fall of Systemic Vascular Resistance Index (SVRI) after OPCAB. Conclusion: Better cardiovascular functioning immediately after OPCAB than ONCAB may be important for better hemodynamic stability. The difference is however eliminated after 24 hours indicating little significance in long term outcome.

PS-BPC05-7: HEMODYNAMIC MANAGEMENT OF RESISTANT HYPERTENSION

Background: Hypertension is the most prevalent chronic disease worldwide and is related to a high probability of cardiac disease, kidney disease and cerebrovascular events. Blood pressure measurement was used in the last decades to diagnose and guide antihypertensive therapy; however blood pressure is the result of the interaction of more complex hemodynamic parameters previously reserved for experimental studies or critical care patients management using invasive methods. Since 1996 few studies have proposed the use of hemodynamic parameters to classify and guide hypertension therapy with good results. Purpose: The present study's purpose was to measure hemodynamic parameters in patients with non-controlled resistant hypertension and use it to guide pharmacologic treatment to archive control blood pressure values according to the European Society of Cardiology guidelines. Methods: A total of 84 patients between 32 and 95 years old diagnosed with non-controlled primary resistant hypertension were recruited and after previous therapy washout hemodynamic parameters were measured using noninvasive Methods: preload by central venous pressure (CVP) using inferior vena cava diameter, cardiac index and systemic vascular resistance using Lyljestrand &amp; Zander modified formula. Patients were classified into 3 basic groups depending on which parameter was above normal value: hyperdynamic (HD) for high cardiac index &gt; 3.5 L/min/m2, fluid overload (FO) for CVP &gt; 8cmH2O and high systemic vascular resistance index (HSVRi) &gt; 2500 dynes/sec/m2/cm5, also 3 combined groups were a patient had 2 simultaneous hemodynamic alterations (HD+FO, HD+HSVRi and FO+HSRVi), according to this classification pharmacotherapy was guided indicating Bisoprolol in HD group, Amlodipine to HSVR patients and Hydrochlorothiazide to FO patients, in combined groups, combined therapy was given. Patients were observed for 6 months period taking as primary endpoint blood pressure control, acute cardiovascular events and hypotension. Results: A significant reduction of hemodynamic parameters and blood pressure was observed in the first month of treatment obtaining a 100% hemodynamic and blood pressure goals in all patients in the third month of therapy without hypotension or acute cardiovascular event during this period, the HD+FO group reach goals at the 6th month of treatment without reported complications. Conclusions: In this preliminary study we observed that hemodynamic guided high blood pressure control may be a valuable tool for a better understanding, classification and treatment in patients with resistant hypertension; however larger outcome studies confirm this hypothesis.

Endotypes of intraoperative hypotension during major abdominal surgery: a retrospective machine learning analysis of an observational cohort study

BackgroundIntraoperative hypotension is associated with myocardial injury, acute kidney injury, and death. In routine practice, specific causes of intraoperative hypotension are often unclear. A more detailed understanding of underlying haemodynamic alterations of intraoperative hypotension may identify specific treatments. We thus aimed to use machine learning – specifically, hierarchical clustering – to identify underlying haemodynamic alterations causing intraoperative hypotension in major abdominal surgery patients. Specifically, we tested the hypothesis that there are distinct endotypes of intraoperative hypotension, which may help refine therapeutic interventions. MethodsWe conducted a secondary analysis of intraoperative haemodynamic measurements from a prospective observational study in 100 patients who had major abdominal surgery under general anaesthesia. We used stroke volume index, heart rate, cardiac index, systemic vascular resistance index, and pulse pressure variation measurements. Intraoperative hypotension was defined as any mean arterial pressure ≤65 mm Hg or a mean arterial pressure between 66 and 75 mm Hg requiring a norepinephrine infusion rate exceeding 0.1 μg kg−1 min−1. To identify endotypes of intraoperative hypotension, we used hierarchical clustering (Ward's method). ResultsA total of 615 episodes of intraoperative hypotension occurred in 82 patients (46 [56%] female; median age: 64 [57, 73] yr) who had surgery of a median duration of 270 (195, 335) min. Hierarchical clustering revealed six distinct intraoperative hypotension endotypes. Based on their clinical characteristics, we labelled these endotypes as (1) myocardial depression, (2) bradycardia, (3) vasodilation with cardiac index increase, (4) vasodilation without cardiac index increase, (5) hypovolaemia, and (6) mixed type. ConclusionHierarchical clustering identified six endotypes of intraoperative hypotension. If validated, considering these intraoperative hypotension endotypes may enable causal treatment of intraoperative hypotension.

Efficacy of Levosimendan in the Treatment of Patients With Severe Septic Cardiomyopathy

This study was designed to compare the effects of levosimendan and dobutamine on hemodynamics and clinical efficacy in patients with severe septic cardiomyopathy (left ventricular ejection fraction [LVEF] ≤35%). A prospective, single-blind, randomized controlled study. In Baoding, China. Thirty patients with severe septic cardiomyopathy treated in the authors' hospital's Department of Critical Medicine from September 2018 to September 2021 were enrolled in this study. These patients were divided randomly into the levosimendan group and dobutamine group. The LVEF, cardiac index (CI), stroke volume index (SVI), systemic vascular resistance index, heart rate, norepinephrine dose, and lactate at the time of enrollment and the 24th hour were compared, along with myocardial injury markers on the third day, C-reactive protein, mechanical ventilation time, length of intensive care unit (ICU) stay, cost, and 28-day mortality. The primary outcome was28-day mortality. At the 24th hour after treatment, CI, LVEF, SVI, and fluid volume were found to be higher in the levosimendan group than in the dobutamine group, whereas the dose of norepinephrine was lower in the former rather than the latter group. On the third day of treatment, cardiac troponin I in the levosimendan group was lower than that in the dobutamine group. Although the differences in 28-day mortality, ICU stay, and ICU treatment cost between the groups were not statistically significant, the ventilator application time of the levosimendan group was significantly shorter than that of the dobutamine group. Compared with dobutamine, levosimendan was more effective at improving cardiac function, reducing myocardial injury, and reducing mechanical ventilation time in patients with severe septic cardiomyopathy.

Analysis of systemic vascular resistance after cardiac surgery: a retrospective cohort study.

Hypotension is a dangerous vital sign frequently encountered during the postoperative management of cardiac surgery. However, factors influencing the systemic vascular resistance index (SVRI), which is strongly related to hypotension, are not well understood. This study evaluated the characteristics of the SVRI according to the type of cardiac surgery. During this retrospective cohort study, we used the clinical data of patients who underwent cardiac surgery at Asahi General Hospital from April 2014 to August 2020. We analyzed their vital signs during the first 12 hours after surgery and evaluated the differences in vital signs among four types of surgery: mitral valve (MV) surgery; aortic valve (AV) surgery; coronary artery bypass grafting (CABG); and thoracic aorta (TA) surgery. Data were compared among these four groups using one-way analysis of variance every 2 hours postoperatively. Those with significant differences were further compared using the post hoc Tukey-Kramer test. A total of 493 patients participated in this study. Overall, the SVRI decreased within 2 hours after the cardiopulmonary bypass surgery. The SVRI after MV surgery was significantly lower than that after other surgery types. The doses of inotropes used for MV surgery and TA surgery were significantly greater than those used for the other surgery types. The SVRI changes significantly after cardiac surgery and may decrease, especially after MV surgery. For better results, it is necessary to consider the differences in the SVRI that are associated with different types of cardiac surgery.

Validation of cardiac output estimation using the fourth-generation FloTrac/EV1000™ system in patients undergoing robotic-assisted off-pump coronary artery bypass surgery.

The pulmonary artery catheter (PAC)-despite its invasiveness-remains the gold standard for cardiac output (CO) monitoring. The FloTrac system, a less invasive hemodynamic monitor has been developed, which estimates CO using arterial pressure waveform analysis without external calibration. Recently, an upgraded version of FloTrac system with improved algorithm to follow changes in vascular resistance was introduced into the market. The aim of this study was to assess the reliability of the CO estimated from the fourth-generation FloTrac/EV1000 system (COFT) compared to that measured with PAC using the thermodilution method (COPAC) during robotic-assisted off-pump coronary artery bypass (OPCAB) surgery. COFT and COPAC were obtained simultaneously at 4 predefined time points during robotic-assisted OPCAB: 5min after the induction of general anesthesia (T1), after starting one-lung ventilation (T2), after capnothorax (T3), and after mini-thoracotomy was performed (T4). The agreement of data was investigated by Bland-Altman analysis. Thirty-four patients were initially enrolled. After exclusion, 32 patients and a total of 128 paired CO measurements were obtained. The overall bias was 1.46L/min, the 95% limits of agreements were - 3.40 to 6.33L/min, and the percentage error was 72.98%. Regression analysis of the systemic vascular resistance index (SVRI) and the bias between COPAC and COFT showed that the bias was moderately correlated with the SVRI (r2 = 0.43; p < 0.0001). Despite a software upgrade, the reliability of the fourth-generation FloTrac/EV1000™ system during robotic-assisted OPCAB to estimate CO was not acceptable, especially in patients with low SVRI.

Comparison of intravenous sildenafil with inhaled nitric oxide for acute vasodilator testing in pulmonary arterial hypertension.

Acute vasodilator testing (AVT) identifies acute responders for initiation of calcium channel blockers in pulmonary arterial hypertension (PAH) and operability in congenital heart disease (CHD). We sought to determine the feasibility of intravenous sildenafil (ivS) as an alternative to inhaled nitric oxide (iNO) in AVT. All patients with PAH undergoing cardiac catheterization for AVT (November 2015 to December 2020) were prospectively enrolled. Hemodynamic data were obtained at baseline, with iNO 20 ppm and ivS (0.25 mg/kg for children and 10 mg for adults). We studied 44 patients with a mean age of 20.5 ± 14.4 years (27 [61%] females and 20 [45%]children). There were 17 (38.6%) patients in theCHD group for operability assessment and 27 patients in non-CHD group (idiopathic pulmonary arterial hypertension-16 [36.3%], residual PAH after shunt closure-7 [15.9%], and 2 cases [4.5%] each of familial PAH and portopulmonary hypertension). There was an excellent intraclass correlation for mean pulmonary artery pressures (0.903, 95% confidence interval,CI: 0.809-0.949, p < 0.001), mean aortic pressures (0.745, 95% CI: 0.552-0.858, p < 0.001), pulmonary vascular resistance index (0.920, 95% CI: 0.858-0.956, p < 0.001), systemic vascular resistance (SVR) index (0.828, 95% CI: 0.706-0.902, p < 0.001), and the ratio of pulmonary and SVR indices (0.857, 95% CI: 0.752-0.919, p < 0.001) between the two agents. There were two responders, both in non-CHD group, and were identified by iNO and ivS. The hemodynamic effects of ivS show excellent correlation with iNO and could be a potential alternative agent for identifying acute responders during AVT.