Lower Mean Arterial Pressure Research Articles

Extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest (OHCA): a four years experience

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Refractory cardiac arrest, defined as the absence of sustained return of spontaneous circulation (ROSC) despite advanced life support (ALS), remains common and is burden by poor outcome. The Extracorporeal Cardiopulmonary Resuscitation (E-CPR) may benefit organ perfusion, potentially improving OHCA outcomes. Purpose The aim of this study was to evaluate outcome of patients with refractory OHCA managed with E-CPR. Methods Single centre prospective observational registry of all patients with OHCA treated with E-CPR from 1 September 2017 to 28 February 2021. The enrolment to E-CPR was defined according to hospital protocol. Results We enrolled 166 patients with OHCA. Out of 59, 39 cases (66,1%) were included in E-CPR program. Prevalence of shockable rhythms was 59%. Survival at discharge from ICU was 10,2% (4 patients; 3 of them discharged with CPC 1-2 and all with ventricular fibrillation at presentation). E-CPR versus patients without refractory arrest have been compared: patients in the E-CPR group were younger (p=0,0002), had lower mean arterial pressure at ROSC and higher SOFA score (p<0,0001). NSE values between survivor (53,8 ± 17,9 mcg/L) and non-survivor (104,8 ± 44,2 mcg/L) at 24 hours were statistically significant (p=0,0669) as well as lactate clearance in the first 48 hours (p=0,001). In the univariate regression model serum lactate at admission (p<0,001; 95% CI 0,87 to 6,83), longer low flow time (p<0,002; 95% CI 0,99 to 1,29) and lower mean arterial pressure (p<0,01; 95% CI 0,99 to 1,29) were associated to mortality. Whereas only lactates (p<0,001; 95% CI 0,092 to 4,56) and low flow time (p<0,001; 95% CI 0,092 to 0,17) retained the association in the multivariate model (figure 1 for ROC curves). Conclusion Mortality rate in OHCA remains unacceptably high. Patients undertaking E-CPR have worsen hemodynamic and clinical parameters at admission, likely to consequence of refractory cardiac arrest. Low-flow time and lactates level are related to higher mortality as expression of worsen metabolic condition related to hypoperfusion state in patients with delayed ROSC.

Maternal B Cell Depletion Reduces Blood Pressure and Improves Fetal Weights in Male Offspring of a Rat Model of Preeclampsia

Preeclampsia (PE), new onset hypertension during pregnancy, is the leading cause of death and morbidity for the mother and low birth weight in offspring. Low birth weight has been shown to cause offspring to be at high risk for cardiovascular and metabolic disorders later in life. PE has been associated with chronic immune activation including T helper cells and natural killer cells. PE women also have activated B cells producing agonistic autoantibodies to the angiotensin II type I receptor (AT1‐AA). AT1‐AA has been implicated in numerous pathways in the pathophysiology of PE. We have shown Rituximab (R), used clinically for B cell depletion, lowers mean arterial pressure (MAP), B cells, and AT1‐AA in the reduced uterine perfusion pressure (RUPP) rat model of PE. Clinical studies show no untoward effects on offspring of pregnant women maintained on R for treating lymphoma. R is not used during PE, therefore, effects of maternal B cell depletion on offspring survival and growth in response to placental ischemia is unknown. We hypothesize that R will deplete maternal B cells in RUPP rats without worsening the effect of placental ischemia on pup growth and survival. To test this hypothesis, the RUPP procedure was performed and R (250 mcg/kg) was given on gestation day (GD) 14 via mini‐osmotic pump. On GD 19, B cells were measured by flow cytometry, and MAP and pup weights were recorded. A separate group of dams were allowed to deliver, pup weights were recorded within 12 hours of birth and weekly until 16 weeks, and B cells were analyzed. A one‐way or two‐way ANOVA was used for statistical analysis. MAP increased in RUPP 123±2 (n=19, p<0.05) compared to NP controls 101±1 (n=18) and was 106±3 mmHg in RUPP+R (n=8, p<0.05). On GD19, maternal circulating B cells were 16±2 % (n=14) in RUPPs, 8±2 % in NP rats, (n=7, p<0.05), and 5.5±1% gate in RUPP+R (n=5, p<0.05). RUPP male and female offspring tended to be smaller (5.11±0.23 g, 5.19±0.14 g; n=4, n=4) at birth than NP offspring (6.09±0.15 g, 5.87±0.12 g; n=6, p<0.064; n=6, p<0.948) or RUPP+R offspring (5.75±0.24 g, 5.36±0.28 g; n=6, p=0.291; n=6, p>0.999). At 12 weeks, male and female RUPP offspring had elevated circulating B cells (21.24±2.92, 20.04±0.72 %; n=6; n=9) compared to NP (1.38±0.23, 1.63±0.06 %; n=4, p<0.05; n=3, p<0.04) which was normalized in RUPP+R offspring (0.40±0.10, 0.27±0.03 % gate; n=3, p<0.05; n=8, p<0.05). At 16 weeks, B cells were comparable in male and female offspring from NP (0.78±0.09 %, n=10; 1.06±0.21 % gate, n=6) and RUPP+R rats (1.21±0.34% gate, n=5; 1.62±0.34% gate, n=5), but were elevated in RUPP male and female offspring (2.45±0.27% gate, n=9; 1.68±0.45% gate, n=13) compared to NP (p<0.05; p>0.99) and RUPP+R (p<0.05; p>0.99). Our findings indicate that R lowers maternal circulating B cells and MAP in RUPP rats and improves fetal weight and circulating B cells, indicating that R does not worsen adverse fetal outcomes in response to placental ischemia.

Resting Sympathetic Transduction in Young Healthy non‐Hispanic Black Women: Potential Race and Sex Differences

BackgroundThe prevalence of hypertension (HTN) is highest in the non‐Hispanic Black (BL) population. Notably, BL women have an equal or greater HTN prevalence compared to BL men; however, limited studies have included women. Heightened sympathetic nervous system reactivity has been proposed as a potential mediator of elevated HTN risk in the BL population. In this regard, our laboratory previously demonstrated exaggerated sympathetic transduction at rest in young normotensive BL men compared to their non‐Hispanic white (WH) counterparts. Whether similar responses are present in BL women is not known. Furthermore, whether there are sex differences in sympathetic transduction in young BL adults remains unclear.HypothesisWe hypothesized that BL women would exhibit elevated resting sympathetic transduction compared to WH women, and that sympathetic transduction would be comparable between BL women and men.MethodsSix young healthy BL women (age: 20 ± 1 years), six WH women (age: 21 ± 1 years) and six BL men (age: 21 ± 1 years) were studied. Heart rate (ECG), muscle sympathetic nerve activity (MSNA; peroneal microneurography) and beat‐to‐beat blood pressure (BP; Finometer) were continuously measured under resting conditions for 19 ± 1 min. Sympathetic transduction was quantified as peak changes in mean arterial pressure (MAP) and the nadir of total vascular conductance (TVC) over 10 cardiac cycles following spontaneous bursts of MSNA using signal‐averaging. All data are expressed as mean ± SEM.ResultsResting BP and heart rate were not different between groups (all P > 0.05). Likewise, BL women had similar MSNA burst frequency (BL women: 12 ± 2 vs. WH women: 14 ± 1 bursts/min; P = 0.475) and burst incidence (BL women: 21 ± 2 vs. WH women: 24 ± 2 bursts/100 cardiac cycles; P = 0.477) compared to WH women, and BL men (13 ± 1 bursts/min, 21 ± 1 bursts/100 cardiac cycles; P = 0.539). For peak increases in MAP following MSNA bursts, there were no differences between BL and WH women (BL women: Δ+2.3 ± 0.4 vs. WH women: Δ+2.1 ± 0.2 mmHg; P = 0.741). Peak reductions in TVC were also not different in women (BL women: Δ‐2.1 ± 0.3 vs. WH women Δ‐2.4 ± 0.6 mL/min/mmHg; P = 0.966). However, in comparison to BL men, BL women had lower MAP (women: Δ+2.3 ± 0.4 vs. men: Δ+5.5 ± 1.1 mmHg; P = 0.011) and TVC (P = 0.036) responses.ConclusionContrary to our hypothesis, these preliminary data suggest similar beat‐to‐beat sympathetic transduction at rest in BL and WH women. Interestingly, sympathetic transduction at rest was lower in BL women compared to BL men highlighting a potential differential effect of sex on BP regulation in young BL adults. Collectively, these findings suggest that augmented sympathetic transduction is not likely an early contributor to the greater prevalence of HTN in BL women.

Therapeutic effects of L‐lysine in Dahl SS rats, a Model of Salt‐Induced Hypertension

Our previous studies have suggested that dual treatment of glomerular filtration and albumin reabsorption might be an effective approach to treating salt‐sensitive (SS) hypertension. L‐lysine, an essential amino acid for humans, has been shown to inhibit tubular protein reabsorption with rapidly increasing urinary albumin excretion in healthy male participants. Our recent metabolomics study revealed that intrarenal levels of L‐Lysine are reduced in Dahl SS rats when animals are fed a high salt diet. In our initial experiments, we tested the effects of L‐lysine during the development of hypertension. We found that L‐lysine administration (17 mg/ml drinking water supplement) in SS rats restores albumin balance, triggers diuresis, and diminishes the development of SS hypertension. In our following experiments, we utilized a therapeutic approach to testing the hypothesis that L‐lysine could decrease the blood pressure of subjects with developed hypertension. The SS rats were initially kept on a 0.4% NaCl diet. When they reached 8‐weeks in age, rats were challenged with an 8% NaCl high salt diet (HS) for 10 days until they exceeded an average mean arterial pressure (MAP) of 140 mmHg (N=13; MAP was measured by implanted telemetry). Then, rats were randomly assigned to treatment and control groups. After another 11 days, all rats were euthanized and tissue was collected for further analyses. At the endpoint, the hypertensive L‐lysine treated rats had significantly lower MAP than hypertensive vehicle‐treated rats (145±5 mmHg vs. 176±8 mmHg). Interestingly, therapy with L‐lysine treatment did not result in a significant difference in diuresis or albuminuria. Excretion for all major electrolytes was comparable between the two groups except for Cl‐ (Cl‐/Creatinine for vehicle vs treated: 142±8 & 209±19). Increased excretion in Cl‐ is most likely due to the administration of L‐lysine as a chloride salt. Preliminary analysis using immunohistochemistry suggests less kidney damage in the treatment group compared to the vehicle group. Therefore, our data propose that L‐lysine, when used as a therapeutic, can effectively treat SS hypertension.

The Relationship Between Short-Term Mean Arterial Pressure Variability and Mortality in Critically Ill Patients.

BackgroundIncreased or decreased blood pressure variability may affect the perfusion of tissues and organs, leading to acute kidney injury and death. This study was conducted to explore the relationship between mean arterial pressure variability and short- and long-term mortality in critically ill patients.MethodsWe used patient data from the MIMIC-III database for cohort study. According to the recorded mean arterial pressure during the first 24 h in the intensive care unit, we calculated each patient’s two variability parameters –coefficient of variation and average real variability. The primary outcome was in-hospital mortality and the secondary outcomes were 28-day mortality and 1-year mortality. We conducted smooth spline models to examine the possible nonlinear associations between blood pressure variability and mortality. According to the smoothing curve, we further developed a two-piecewise linear regression model to find out the threshold effect. Multivariable logistic regression or Cox proportional hazards model was used to evaluate the relationship. Kaplan–Meier survival analysis for 28-day and 1-year mortality was performed. Subgroup analysis explored the factors modifying the relationship between them.ResultsA total of 12,867 patients were enrolled in the study, 1,320 in-hospital death, 1,399 28-day death, and 2,734 1-year death occurred. The smooth spline showed death risk was the lowest when average real variability was around 7.2 mmHg. After adjusting for covariates, logistic or Cox regression showed the highest MAP variability level was strongly associated with increased mortality in the hospital (odds ratio: 1.44; 95% CI, 1.21∼1.72), at 28 days (hazard ratio: 1.28; 95% CI, 1.1∼1.5), and at 1 year (hazard ratio: 1.27; 95% CI, 1.14∼1.42) compared with the second level of average real variability group. The survival curve plot showed patients with higher average real variability had a higher risk of 28-day and 1-year mortality. This relationship remained remarkable in patients with low or high Sequential Organ Failure Assessment scores in the sensitivity analysis. The two-piecewise linear regression model showed that lower ARV was a risk factor for 28-day (HR 0.72, 95% CI, 0.57∼0.91) and 1-year mortality (HR 0.81, 95% CI, 0.68∼0.96) when ARV was less than 7.2 mmHg, higher ARV was a risk factor for 28-day mortality (HR 1.1, 95% CI, 1.04∼1.17) and 1-year mortality (HR 1.07, 95% CI, 1.02∼1.12) when ARV was greater than 7.2 mmHg.ConclusionBlood pressure variability predicts mortality in critically ill patients. Individuals with higher or lower mean arterial pressure average real variability during the first day in ICU may have an increased risk of death.

Targeting Depth of Anesthesia to Prevent Delirium: Comment

Brown et al.1 nicely described their work comparing spinal anesthesia with targeted sedation based on Bispectral Index values compared with general anesthesia (masked Bispectral Index) and the outcome of delirium. Intraoperative hypotension has been associated with delirium.2,3 The adjusted hazard ratio associated with a 1-mmHg increase in time-weighted average of mean arterial pressure less than 65 mmHg was 1.11 (95% CI, 1.03 to 1.20).2 The study by Brown et al.1 found that the lowest mean arterial pressure was similar in both groups (general anesthesia, 59 [51 to 64] vs. spinal anesthesia, 60 [52 to 64]); however, the relationship between intraoperative hypotension and the subsequent development of delirium might be more of a cumulative exposure response than a single threshold. It would be of interest to know the hypotension exposure by time under the 65- or 60-mmHg threshold and to consider that in a treatment-by-covariate interactions analysis. In short, we appreciate Brown et al. for their great contributions to this important topic.Supported by grant No. (2018)5779-51 from the Academic New Seedling Cultivation and Innovation Exploration Special Project of Guizhou Medical University (Guiyang, China) in 2018 and grant No. gzwjkj2020-1-132 from the Science and Technology Foundation of Guizhou Provincial Health Commission (Guiyang, China).The authors declare no competing interests.

Arterial hypotension in patients with essential hypertension II–III: unresolved issues and ambulatory blood pressure monitoring diagnostic criteria

The aim was to study the prevalence of sustained arterial hypotension in high cardiovascular risk patients with II–III stage essential hypertension and associated factors. Materials and methods. Patients with II–II stage essential hypertension and sinus rhythm (n = 179, mean age 61 (95 % CI: 59.6‒62.5) years, 57.0 % were males) underwent ambulatory blood pressure monitoring (ABPM). Arterial hypotension episodes were evaluated according to the blood pressure (BP) office measurement (<110/70 mm Hg) and ABPM over 24 hours (<100/60 mm Hg), daytime (<105/65 mm Hg) and nighttime (<90/50 mm Hg). To determine the covariates associated with the probability of arterial hypotension, models were constructed using binary logistic regression analysis. Results. There was an almost threefold increase in the prevalence of arterial hypotension according to ABPM (6.2 %, 11/179), compared with the results of office measurement (2.2 %, 4/179). The prevalence of masked arterial hypotension was 63.6 %. Hypotension episodes (n = 22) were detected in 11 patients mainly during the daytime (13/22). Hypotension was represented by a significant percentage of people with isolated diastolic (81.8 %) and lower – with systo-diastolic fall in BP (18.2 %). Hypotension associated risk factors were reaching the target level of intensive BP control, lower mean arterial pressure (24-hour time, daytime, nighttime analysis), its extreme dipping pattern, and female sex. Conclusions. The method of ABPM has advantages over office BP measurement in detecting episodes of sustained arterial hypotension. The risk of developing hypotension is increased in intensive BP control. The sustained hypotension is associated with lower mean arterial pressure values, its extreme dipping pattern and female sex.

The impact of cardiovascular comorbidities associated with risk for left heart disease on idiopathic pulmonary arterial hypertension: Data from the Hellenic Pulmonary Hypertension Registry (HOPE).

Whereas younger female patients were diagnosed with idiopathic pulmonary arterial hypertension (IPAH) in 1980s, it is now frequently encountered in elderly patients with cardiovascular comorbidities (CVCs) associated with increased risk for left heart disease. We present data until November 2019 regarding specific features and clinical outcomes of IPAH population from the Hellenic Pulmonary Hypertension Registry (HOPE). Patients were divided into two groups based on the presence of ≥ or <3 CVCs, arterial hypertension, diabetes mellitus, obesity, presence of coronary artery disease, or atrial fibrillation. Overall, 77 patients with IPAH (55.1 [interquartile range, IQR: 24.1] years, 62.8% women) have been recorded. Fifteen patients (19.2%) had ≥3 CVCs, while 25 (32%) were over 65 years old. Patients with ≥3 CVCs were older, presented an almost equal female to male ratio, walked less in 6‐min walk test, and had lower mean arterial pulmonary pressure and pulmonary vascular resistance at baseline than patients with less CVCs. Fewer patients with ≥3 CVCs received PAH‐specific treatment compared to patients with less comorbidities (n = 11 [73.3%] versus n = 58 [95.5%], p = 0.02). During a median follow‐up period of 3.8 (IQR: 2.7) years, 18 patients died (all‐cause mortality 24.3%). Male sex and older age were independent predictors of mortality and/or lung transplantation, while CVCs did not have a significant impact on clinical outcomes. In this nationwide, register‐based study, the epidemiology of IPAH involves older patients with CVCs, who seem to have less hemodynamic compromise, but worse functional impairment and are treated less aggressively with PAH pharmacotherapy.

A nomogram to predict prolonged postoperative ileus after intestinal resection for Crohn's disease.

We aim to identify the risk factors of PPOI in patients with CD and create a nomogram for prediction of PPOI for CD. Data on 462 patients who underwent partial intestinal resection for CD in Jin-ling Hospital between January 2019 and June 2021 were retrospectively collected. Univariate and multivariate analyses were performed to determine the risk factors for PPOI and we used the risk factors to create a nomogram. Then we used the Bootstrap-Concordance index and calibration diagrams to evaluate the performance of the Nomogram. Decision curve analysis was performed to evaluate clinical practicability of the model. The incidence of PPOI was 27.7% (n of N). Course of CD ≥ 10years, operation time ≥ 154min, the lowest mean arterial pressure ≤ 76.2mmHg, in-out balance per body weight ≥ 22.90ml/kg, post-op day 1 infusion ≥ 2847ml, post-op lowest K+ ≤ 3.75mmol/L, and post-op day 1 procalcitonin ≥ 2.445ng/ml were identified as the independent risk factors of PPOI in patients with CD. The nomogram we created by these risk factors presented with good discriminative ability (concordance index 0.723) and was moderately calibrated (bootstrapped concordance index 0.704). The results of decision curve analysis showed that the nomogram was clinically effective within probability thresholds in the 8 to 66% range. The nomogram we developed is helpful to evaluate the risk of developing PPOI after partial intestinal resection for CD. Clinicians can take more necessary measures to prevent PPOI in CD's patients or at least minimize the incidence.

The impact of the surgical Apgar score on oncological outcomes in patients with colorectal cancer: a propensity score-matched study

BackgroundThe surgical Apgar score (SAS) predicts postoperative complications (POCs) following gastrointestinal surgery. Recently, the SAS was reported to be a predictor of not only POCs but also prognosis. However, the impact of the SAS on oncological outcomes in patients with colorectal cancer (CRC) has not been fully examined. The present study therefore explored the oncological significance of the SAS in patients with CRC, using a propensity score matching (PSM) method.MethodsWe retrospectively analyzed 639 patients who underwent radical surgery for CRC. The SAS was calculated based on three intraoperative parameters: estimated blood loss, lowest mean arterial pressure, and lowest heart rate. All patients were classified into 2 groups based on the SAS (≤6 and >6). The association of the SAS with the recurrence-free survival (RFS), overall survival (OS), and cancer-specific survival (CSS) was analyzed.ResultsAfter PSM, each group included 156 patients. Univariate analyses revealed that a lower SAS (≤6) was significantly associated with a worse OS and CSS. A multivariate analysis revealed that the age ≥75 years old, ASA-Physical Status ≥3, SAS ≤6, histologically undifferentiated tumor type, and an advanced pStage were independent factors for the OS, and open surgery, a SAS ≤6, histologically undifferentiated tumor type and advanced pStage were independent factors for the CSS.ConclusionsA lower SAS (≤6) was an independent prognostic factor for not only the OS but also the CSS in patients with CRC, suggesting that the SAS might be a useful biomarker predicting oncological outcomes in patients with CRC.

Cardiac Tamponade in Eisenmenger Syndrome: A Diagnosing Complexity: Case Report

Cardiac tamponade is a form of obstructive shock with clinical manifestations consistent with a low cardiac output and high central venous pressure. Features of a low cardiac output include low mean arterial pressure, cold peripheries and signs of poor end-organ perfusion. Characteristically, palpating the pulse reveals an apparent variation in pulse volume because of pulsus paradoxus. Jugular venous pressure is typically increased, with distended neck veins apparent. Sympathetic tone is increased in an attempt to compensate for the low cardiac output and manifests as tachycardia, diaphoresis, anxiety [1] and poor distal perfusion determining the need for emergent Pericardiocentesis. We report a case where an hemodynamically significant pericardial effusion with indication of pericardiocentesis had presented without classic signs of tamponade. It is an unusual and rare case of large pericardial effusion in the setting of Eisenmenger syndrome where only clinical signs as worsening hypoxia and cyanosis due to the right to left shunt was the warning sign of cardiac tamponade requiring pericardiocentesis.

Antihypertensive and Vasorelaxant Effects of Hibiscus rosa-sinensis through Angiotensin-Converting Enzyme-2 (ACE-2), and Ca2+ channels Pathways.

The aim of the study was to assess the antihypertensive activity of Hibiscus rosa-sinensis. Hibiscus rosa-sinensis is used traditionally to treat hypertension. The goal of the study was to investigate the effect of the aqueous extract of Hibiscus rosa-sinensis flowers (AEHRS) on resting blood pressure in rats. In the present study, AEHRS was prepared and its antihypertensive activity was evaluated using in vivo and in vitro studies. In the in vivo study, hypertensive and normotensive rats were treated by AEHRS (100 mg/kg) orally for 6 hours in the acute treatment and for 7 days in the subchronic treatment. Systolic, diastolic, and mean arterial blood pressure values and heart rate were then recorded using a tail cuff and a computer-assisted monitoring device. To assess the vasorelaxant activity of AEHRS, isolated thoracic aortic rings were suspended in a tissue bath and changes in tension were recorded using a data acquisition system. Potential pathways involved in the vasorelaxant activity were evaluated using several standard pharmacological agents. The results indicated that repeated oral administration of AEHRS during 7 days lowered systolic, diastolic, and mean arterial blood pressure in hypertensive rats without affecting normotensive rats. Furthermore, the data revealed that AEHRS exerts vasorelaxant properties via an endothelium-independent pathway. More interestingly, the study demonstrates that the vasorelaxant capacity of AEHRS seems to be exerted through the stimulation of angiotensin-converting enzyme-2 (ACE-2) and the inhibition of Ca2+ channels pathway. The present study revealed that aqueous extract of Hibiscus rosa-sinensis has a significant antihypertensive activity and that its vasorelaxant effect may be mediated through stimulation of ACE-2, and inhibition of the Ca2+ channels.

Application of Machine Learning Algorithms to Predict Acute Kidney Injury in Elderly Orthopedic Postoperative Patients.

ObjectiveThere has been a worldwide increment in acute kidney injury (AKI) incidence among elderly orthopedic operative patients. The AKI prediction model provides patients’ early detection a possibility at risk of AKI; most of the AKI prediction models derive, however, from the cardiothoracic operation. The purpose of this study is to predict the risk of AKI in elderly patients after orthopedic surgery based on machine learning algorithm models.MethodsWe organized a retrospective study being comprised of 1000 patients with postoperative AKI undergoing orthopedic surgery from September 2016, to June, 2021. They were divided into training (80%;n=799) and test (20%;n=201) sets.We utilized nine machine learning (ML) algorithms and used intraoperative information and preoperative clinical features to acquire models to predict AKI. The performance of the model was evaluated according to the area under the receiver operating characteristic (AUC), sensitivity, specificity and accuracy. Select the optimal model and establish the nomogram to make the prediction model visualization. The concordance statistic (C-statistic) and calibration curve were used to discriminate and calibrate the nomogram respectively.ResultsIn predicting AKI, nine ML algorithms posted AUC of 0.656–1.000 in the training cohort, with the randomforest standing out and AUC of 0.674–0.821 in the test cohort, with the logistic regression model standing out. Thus, we applied the logistic regression model to establish nomogram. The nomogram was comprised of ten variables: age, body mass index, American Society of Anesthesiologists, hypoproteinemia, hypertension, diabetes, anemia, duration of low mean arterial pressure, mean arterial pressure, transfusion.The calibration curves showed good agreement between prediction and observation in both the training and test sets.ConclusionBy including intraoperative and preoperative risk factors, ML algorithm can predict AKI and logistic regression model performing the best. Our prediction model and nomogram that are based on this ML algorithm can help lead decision-making for strategies to inhibit AKI over the perioperative duration.

Assessment of Fluid Responsiveness With End Tidal Carbon Dioxide Using A Simplified LegRaising Maneuver in Non-Cardiac Patients Admitted in Medical Intensive Care Unit

Objective: To assess the fluid responsiveness with end tidal carbon dioxide using a simplified leg-raising maneuver in noncardiac patients admitted in medical Intensive Care Unit (ICU).&#x0D; Study Design: Cross sectional analytical study.&#x0D; Place and Duration of Study: Intensive Care Unit, Pak Emirates Military Hospital Rawalpindi, form Jun to Nov 2019.&#x0D; Methodology: A total of 80 cases were included in this study who were admitted in medical ICU and were on ventilator support. A standard 5-minute leg-raising maneuver was applied on all the patients. An increase in cardiac index &gt;15% after passive leg rise was taken as criteria for responders. All echocardiographic evaluations were performed by experienced sonographers.&#x0D; Results: Mean age of study participants was 47.4 ± 4.421 years, 65 (81.3%) were males while 15 (18.7%) were female patients. Sixty (75%) patients responded to the simplified leg raising maneuver while 20 (25%) did not respond. Mean arterial pressure of the respondents was 92.3 ± 3.26 mmHg while mean arterial pressure of the non-respondents was 83.2 ± 4.57 mmHg. High body mass index and low mean arterial pressure had statistically significant relationship with no response to the maneuver in our study.&#x0D; Conclusion: Simplified leg raising emerged as an effective maneuver to stabilize the non-cardiac patients hemodynamically inside the setting of critical care unit. Patients with low baseline mean arterial pressure or high body mass index may be considered as high risk for non-response to this maneuver.

Utility of the surgical Apgar score in predicting morbidity and mortality: A prospective study

IntroductionOptimization of postoperative care is often contingent upon the risk stratification tools such as surgical scores that are used to prognosticate potential complications.AimThis study evaluates the utility of surgical Apgar score (SAS) as a tool to predict morbidity and 30-day mortality among patients post general surgical procedures.Material and methodsThe study cohort comprised of 400 patients aged between 15 to 75 years, and prospectively undergoing emergency or elective general surgery. SAS of patients were extracted from the anesthesiologist’s records on estimated blood loss, lowest heart rate and lowest mean arterial pressure. Post-operative outcomes such as major complications and mortality within 30 days of surgery were monitored.Results and DiscussionOut of the 297 elective procedures, 22 (7.41%) cases had major complications. While among those undergoing emergency surgeries (103), 38 (36.86%) patients developed major complications. The odds of developing major complications in patients with the high-risk SAS scores (31; 51.67%) was 5.42 (CI: 3.03–9.70) times greater than in patients with low-risk SAS scores (29; 48.33%). The odds of expiring after a general surgery was 11.92 times higher in high-risk patients (9; 75%) when contrasted with low-risk patients (3; 25%). The sensitivity and specificity of SAS in predicting major complications is 51.67% and 83.53%, respectively. The sensitivity and specificity of SAS in predicting mortality are 75% and 79.9%, respectively.ConclusionsSAS serves as a simple and dependable tool to predict morbidity and 30-day mortality in patients undergoing surgical procedures under anesthesia other than local, requiring intensive perioperative monitoring.

Placental CD4+ T cells from preeclamptic patients cause autoantibodies to the angiotensin II type I receptor and hypertension in a pregnant rat model of preeclampsia.

Preeclampsia (PE) is a hypertensive disorder of pregnancy associated with activated CD4+ T cells and autoantibodies to angiotensin II type 1 receptor (AT1-AA). We have previously shown that CD4+ T cells isolated from women with PE cause hypertension, increased tumor necrosis factor alpha (TNF-α), endothelin-1, and soluble fms-like tyrosine kinase-1 (sFlt-1) when injected into pregnant nude-athymic rats compared to CD4+ T cells from normal pregnant (NP) women. However, the role of PE CD4+ T cells to cause AT1-AA as a mechanism of hypertension is not known. Aim: Our goal was to determine if PE CD4+ T cells stimulate AT1-AA in pregnant nude-athymic rats. CD4+ T cells were isolated from human NP and PE placentasand injected into nude-athymic rats on gestational day (GD) 12. In order to examine the role of the PE CD4+ T cells to stimulate B cell secretion of AT1-AA, a subset of the rats receiving PE CD4+ T cells were treated with rituximab on GD 14 or anti-CD40 ligand (anti-CD40L) on GD 12. On GD 19, mean arterial pressure (MAP) and tissues were obtained MAP [114 ± 1 mmHg (n = 9)] and AT1-AA [19.8 ± 0.9 beats per minute (bpm, n = 4)] were increased in NP nude + PE CD4+ T cells compared to NP nude + NP CD4+ T cells [98 ± 2 mmHg (n = 7, P < 0.05) and 1.3 ± 0.9 bpm (n = 5, P < 0.05)]. Rituximab (103 ± 2 mmHg, n = 3, P < 0.05) and anti-CD40L (102 ± 1 mmHg, n = 3, P < 0.05) lowered MAP compared to NP nude + PE CD4+ T cells. Circulating a proliferation-inducing ligand (APRIL) and placental angiotensin-converting enzyme 2 (ACE-2) activity was increased in response to PE CD4+ T cells. These results show that placental CD4+ T cells play an important role in the pathophysiology of PE, by activating B cells secreting AT1-AA to cause hypertension during pregnancy.

Increased risk of hip fracture mortality associated with intraoperative hypotension in elderly hip fracture patients is related to under resuscitation

BackgroundAs the US and world population ages, hip fractures are increasingly more common. The mortality associated with these fractures remains high both in the immediate postoperative period and at one year. Perioperative resuscitation in this population is of key interest to prevent organ injury and mortality. Our objectives were to evaluate the effect of fluid resuscitation and hemodynamic status in the form of mean arterial pressure (MAP) on inpatient mortality of hip fracture patients. MethodsAn institutional database was queried to compare elderly hip fracture patients that sustained in-hospital mortality to a matched control cohort. Pre-, intra-, and post-operative intravenous fluid (IVF) administration and MAP were extracted from the electronic medical record. Time from hospital presentation to the OR was also recorded. Results1,114 total hip fractures were identified during the two-year study period, 16 of which suffered inpatient mortalities. The mortality cohort was then matched with a control of 394 hip fracture patients for the same period based on age, sex, and Charlson Comorbidity Index (CCI). Conditional logistical regression analysis found odds ratios (OR) indicating that longer time between presentation and surgery (OR per additional hour: 1.05; 95% CI: 1.01–1.08) and lower intraoperative minimum MAP (OR per 5 mmHg decrease: 0.77; 95% CI: 0.61–0.97) were associated with significantly increased odds of mortality. There was also a marginal relationship between greater intraoperative IVF administration and reduced odds of mortality (OR per 500 cc additional fluid: 0.61; 95% CI: 0.37–1.00). ConclusionExtended time from presentation to surgery and intraoperative hypotension were associated with increased likelihood of inpatient mortality in an elderly hip fracture cohort, with a possible additional effect of under-resuscitation. Further investigation into a safe intraoperative minimum MAP should be pursued. Level of evidenceLevel III.

Differences between intertrochanteric and femoral neck fractures in resuscitative status and mortality rates

IntroductionHip fracture mortality remains a challenge for orthopedic surgeons. The purpose of this study was to compare resuscitative mean arterial pressures (MAPs), intravenous fluid (IVF) administration, and mortality rates between intertrochanteric (IT) and femoral neck (FN) fracture patients. HypothesisWe hypothesized that IT fracture patients would receive less aggressive fluid resuscitation than FNF patients given the perceived less invasive nature of intra-medullary nails compared with hemiarthroplasty. Materials and methodsAn institutional database was queried to identify all hip fractures managed surgically over a 2-year period. Preoperative and intraoperative MAPs and IVF administration, as measures of resuscitation, were compared between IT fracture patients treated with open reduction internal fixation and FN fracture patients treated with hemiarthroplasty. ResultsSix hundred and ninety-eight hip fractures, including 531 IT and 167 FN fractures, were analyzed. There were no differences between IT and FN fracture cohorts for age, sex distribution, or Charlson Comorbidity Index scores. IT fracture patients were found to have lower MAP upon admission (103.7±20.1 vs. 107.8±18.4mmHg; p=0.026), and lower average, minimum, and maximum MAP values preoperatively and intraoperatively. Despite lower MAPs, IT fracture patients received less total IVF (581.9±472.5 vs. 832.9±496.5cc; p<0.001) and lower IVF rates intraoperatively (306.5±256.8 vs. 409.8±251.0 cc/h; p<0.001). IT fracture patients experienced higher 30-day (7.9% vs. 3.6%; p=0.040) and 90-day (10.6% vs. 5.4%; p=0.035) mortality rates and trended towards higher inpatient mortality (3.0% vs. 0.6%; p=0.088). Multivariate regression demonstrated IT pattern to be independently predictive of 30-day mortality with 2.459 increased odds relative to FN fracture (p=0.039). DiscussionIT fracture patterns are associated with decreased perioperative MAP values, yet received lower perioperative IVF rates. IT fracture patients suffered higher 30- and 90-day mortality rates, despite similar age and comorbidities. Level of evidenceIII; retrospective cohort study.

Abstract 91: Large Vessel Occlusion Stroke Patients With Rapid Early Infarct Progression And Poor Collaterals Are Vulnerable To Blood Pressure Reductions

Introduction: The precise interactions between collateral perfusion, hemodynamics, and infarct growth after large vessel occlusion (LVO) require further definition. This study examined whether patients with poor collateral circulation and rapid early infarct progression are more vulnerable to reductions in blood pressure (BP). Methods: We prospectively enrolled patients with LVO stroke who underwent thrombectomy. Volumes of arterial tissue delay and relative cerebral blood flow (CBF) were estimated with RAPID software; a poor collateral profile was defined by a hypoperfusion intensity ratio &gt;0.4. Early infarct growth rate (EIGR) was defined as ischemic core volume (CBF&lt;30%) divided by the time from symptom onset to imaging. A fast progressor profile was assigned to patients whose EIGR was &gt;10 mL/h. The final infarct growth rate (FIGR) was the quotient of final infarct volume (FIV) and time from symptom onset to reperfusion. BP reduction was measured as the difference between admission mean arterial pressure (MAP) and lowest MAP before reperfusion. Results: Fifty-five patients (mean age 69 + 15, mean NIHSS 13) with successful reperfusion (TICI 2B/3) were included in the analysis. The median MAP reduction was 17 (IQR 9, 32). Poor collateral perfusion and EIGR were independent predictors of FIV after adjusting for age and admission NIHSS (mean FIV 70 vs. 31 mL, p=0.012 and 60 vs. 29 mL, p=0.01, respectively). A significant interaction was found between MAP reduction and both collateral status (p=0.04) and progressor profile (p=0.01). For every 10 mmHg MAP reduction, patients with poor collaterals experienced an average increase in FIGR of 3.6 mL/h (Fig. 1A). Above a critical MAP reduction threshold of 30 mmHg, mean FIV was significantly larger in patients with rapidly progressing infarcts (p&lt;0.01, Fig. 1B). Conclusions: Patients with poor collaterals and rapid early infarct growth are at higher risk of accelerated infarct growth and larger FIV related to BP reductions.

Thoracic Epidural Versus General Anaesthesia For Laparoscopic Cholecystectomy: A Randomized Controlled Trial.

Laparoscopic cholecystectomy is one of the most commonly performed surgeries worldwide. Aim of our study was to compare the effectiveness of thoracic epidural anaesthesia with general anaesthesia for Laparoscopic cholecystectomy in terms of changes in blood pressure during surgery, postoperative pain, respiratory complications and average length of hospital stay. It was a randomized controlled trial conducted from 1stOctober 2018 to 31st October 2019. Eightytwo patients planned to undergo elective laparoscopic cholecystectomy were randomly divided into two groups, T and G. In Group T all patients underwent laparoscopic cholecystectomy under thoracic epidural anaesthesia with 12 ml of 0.25% bupivacaine and 1% lignocaine plain whereas in group G all patients underwent surgery under general anaesthesia. Intra-operative mean arterial pressure (MAP) and postoperative opioid consumption in first 24hrs were recorded as primary outcomes whereas presence or absence of respiratory complication and duration of hospital stay as secondary outcome.. Out of 82 patients, 41 patients underwent laparoscopic cholecystectomy under thoracic epidural anaesthesia and 41 patients had surgery under general anaesthesia. Mean arterial pressure was lower in Group T and the difference was statistically significant. The average time of first complaint of postoperative pain in Group T was 5.4±1.26 hours as compared to less than 0.79±0.25 hours in Group G. Patients in group T required lower doses of opioid analgesia in first twenty-four hours as compared to patients in group G. Mean hospital stay in group T was 1 day as compared to 3 days in group G. Thoracic epidural anaesthesia provides a better alternative to general anaesthesia for Laparoscopic cholecystectomy with lower intraoperative mean arterial blood pressure, 24 hours postoperative consumption of opioids, respiratory complications and length of hospital stay.