Vasoactive-Inotropic Score: Evolution, Clinical Utility, and Pitfalls

Prediction of successful weaning from renal replacement therapy in critically ill patients based on machine learning

BACKGROUND

Predicting the successful weaning of acute kidney injury (AKI) patients from renal replacement therapy (RRT) has emerged as a research focus, and we successfully built predictive models for RRT withdrawal in patients with severe AKI by machine learning.

METHODS

This retrospective single-center study utilized data from our general intensive care unit (ICU) Database, focusing on patients diagnosed with severe AKI who underwent RRT. We evaluated RRT weaning success based on patients being free of RRT in the subsequent week and their overall survival. Multiple logistic regression (MLR) and machine learning algorithms were adopted to construct the prediction models.

RESULTS

A total of 976 patients were included, with 349 patients successfully weaned off RRT. Longer RRT duration (7.0 vs. 9.6 d, p = 0.002, OR = 0.94), higher serum cystatin C levels (1.2 vs. 3.2 mg/L, p < 0.001, OR = 0.46), and the presence of septic shock (28.1% vs. 41.5%, p < 0.001, OR = 0.63) were associated with reduced likelihood of RRT weaning. Conversely, a positive furosemide stress test (FST) (60.2% vs. 40.7%, p < 0.001, OR = 2.75) and higher total urine volume 3 d before RRT withdrawal (755 vs. 125 mL/d, p < 0.001, OR = 2.12) were associated with an increased likelihood of successful weaning from RRT. Next, we demonstrated that machine learning models, especially Random Forest and XGBoost, achieving an AUROC of 0.95. The XGBoost model exhibited superior accuracy, yielding an AUROC of 0.849.

CONCLUSION

High-risk factors for unsuccessful RRT weaning in severe AKI patients include prolonged RRT duration. Machine learning prediction models, when compared to models based on multivariate logistic regression using these indicators, offer distinct advantages in predictive accuracy.

Protracted fibrinolysis resistance following cardiac surgery with cardiopulmonary bypass: A prospective observational study of clinical associations and patient outcomes

BACKGROUND

Surgery on cardiopulmonary bypass (CPB) elicits a pleiomorphic systemic host response which, when severe, requires prolonged intensive care support. Given the substantial cross-talk between inflammation, coagulation, and fibrinolysis, the aim of this hypothesis-generating observational study was to document the kinetics of fibrinolysis recovery post-CPB using ClotPro® point-of-care viscoelastometry. Tissue plasminogen activator-induced clot lysis time (TPA LT, s) was correlated with surgical risk, disease severity, organ dysfunction and intensive care length of stay (ICU LOS).

RESULTS

In 52 patients following CPB, TPA LT measured on the first post-operative day (D1) correlated with surgical risk (EuroScore II, Spearman's rho .39, p < .01), time on CPB (rho = .35, p = .04), disease severity (APACHE II, rho = .52, p < .001) and organ dysfunction (SOFA, rho = .51, p < .001) scores, duration of invasive ventilation (rho = .46, p < .01), and renal function (eGFR, rho = -.65, p < .001). In a generalized linear regression model containing TPA LT, CPB run time and markers of organ function, only TPA LT was independently associated with the ICU LOS (odds ratio 1.03 [95% CI 1.01-1.05], p = .01). In a latent variables analysis, the association between TPA LT and the ICU LOS was not mediated by renal function and thus, by inference, variation in the clearance of intraoperative tranexamic acid.

CONCLUSIONS

This observational hypothesis-generating study in patients undergoing cardiac surgery with cardiopulmonary bypass demonstrated an association between the severity of fibrinolysis resistance, measured on the first post-operative day, and the need for extended postoperative ICU level support. Further examination of the role of persistent fibrinolysis resistance on the clinical outcomes in this patient cohort is warranted through large-scale, well-designed clinical studies.

Clinical Outcomes and Determinants of Survival in Patients with Hematologic Malignancies Admitted to Intensive Care Units with Critical Illness

Outcomes of patients with hematologic malignancies requiring ICU care for critical illness are suboptimal and represent a major unmet need in this population. We present data from a dedicated haematology oncology setting including 63 patients with a median age of 60 years admitted to the ICU for critical illness with organ dysfunction. The most common underlying diagnosis was multiple myeloma (30%) followed by acute myeloid leukemia (25%). Chemotherapy had been initiated for 90.7% patients before ICU admission. The most common indication for ICU care was respiratory failure (36.5%) and shock (17.5%) patients. Evidence of sepsis was present in 44 (69%) patients. After shifting to ICU, 32 (50%) patients required inotropic support and 18 (28%) required invasive mechanical ventilation. After a median of 5 days of ICU stay, 43.1% patients had died, most commonly due to multiorgan dysfunction. Risk of mortality was higher with involvement of more than two major organs (p = .001), underlying AML (p = .001), need for mechanical ventilation (p = .001) and high inotrope usage (p = .004). Neutropenia was not associated with mortality. Our study indicates high rates of short term mortality and defines prognostic factors which can be used to prognosticate patients and establish goals of care.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12288-024-01757-3.

A Retrospective Analysis of Risk Factors and Impact of Acute Kidney Injury in Critically Ill Children

BACKGROUND

Acute kidney injury (AKI) is a serious clinical condition in critically ill children and is associated with worse outcomes. A few pediatric studies focused on the risk factors of AKI. We aimed to identify the incidence, risk factors, and outcomes of AKI in the pediatric intensive care unit (PICU).

PATIENTS AND METHODS

All the patients admitted to PICU over a period of 20 months were included. We compared both groups the risk factors between AKI and non-AKI.

RESULTS

A total of 63 patients (17.5%) of the 360 patients developed AKI during PICU stay. The presence of comorbidity, diagnosis of sepsis, increased PRISM III score, and positive renal angina index were found to be risk factors for AKI on admission. Thrombocytopenia, multiple organ failure syndrome, the requirement of mechanical ventilation, use of inotropic drugs, intravenous iodinated contrast media, and exposure to an increased number of nephrotoxic drugs were independent risk factors during the hospital stay. The patients with AKI had a lower renal function on discharge and had worse overall survival.

CONCLUSIONS

AKI is prevalent and multifactorial in critically sick children. The risk factors of AKI may be present on admission and during the hospital stay. AKI is related to prolonged mechanical ventilation days, longer PICU stays, and a higher mortality rate. Based on the presented results early prediction of AKI and consequent modification of nephrotoxic medication may generate positive effects on the outcome of critically ill children.

Vasoactive-Inotropic Score as a Promising Predictor of Acute Kidney Injury in Adult Patients Requiring Extracorporeal Membrane Oxygenation

Acute kidney injury (AKI) is a common complication in patients supported by extracorporeal membrane oxygenation (ECMO). Vasoactive-Inotropic Score (VIS) serves as an indicator of the extent of cardiovascular drug support provided. Our objective is to assess the relationship between the VIS and ECMO-associated AKI (EAKI). This single-center retrospective study extracted adult patients treated with ECMO between August 2016 and September 2022 from an intensive care unit (ICU) in a university hospital. A total of 126 patients requiring ECMO support were included in the study, of which 76% developed AKI. Multivariate logistic regression analysis identified VIS-max Day1 (odds ratio [OR]: 1.025, 95% confidence interval [CI]: 1.007-1.044, p = 0.006), VIS-max Day2 (OR: 1.038, 95% CI: 1.007-1.069, p = 0.015), VIS-mean Day1 (OR: 1.048, 95% CI: 1.013-1.084, p = 0.007), and VIS-mean Day2 (OR: 1.059, 95% CI: 1.014-1.107, p = 0.010) as independent risk factors for EAKI. VIS-max Day1 showing the best predictive effect (Area under the receiver operating characteristic curve (AUROC): 0.80, sensitivity: 71.87%, specificity: 80.00%) for EAKI with a cutoff value of 33.33. Surprisingly, VIS-mean Day2 was also excellent at predicting 7 day mortality (AUROC: 0.77, sensitivity: 87.50%, specificity: 56.38%) with a cutoff value of 8.67. In conclusion, VIS could independently predict EAKI and 7 day mortality in patients with ECMO implantation, which may help clinicians to recognize the poor prognosis in time for early intervention.

Acute normovolemic hemodilution in cardiac surgery: rationale and design of a multicenter randomized trial

BACKGROUND

Minimizing the use of blood component can reduce known and unknown blood transfusion risks, preserve blood bank resources, and decrease healthcare costs. Red Blood Cell (RBC) transfusion is common after cardiac surgery and associated with adverse perioperative outcomes, including mortality. Acute normovolemic hemodilution (ANH) may reduce bleeding and the need for blood product transfusion after cardiac surgery. However, its blood-saving effect and impact on major outcomes remain uncertain.

METHODS

This is a single-blinded, multinational, pragmatic, randomized controlled trial with a 1:1 allocation ratio conducted in Tertiary and University hospitals. The study is designed to enroll patients scheduled for elective cardiac surgery with planned cardiopulmonary bypass (CPB). Patients are randomized to receive ANH before CPB or the best available treatment without ANH. We identified an ANH volume of at least 650 ml as the critical threshold for clinically relevant benefits. Larger ANH volumes, however, are allowed and tailored to the patient's characteristics and clinical conditions.

RESULTS

The primary outcome is the percentage of patients receiving RBCs transfusion from randomization until hospital discharge, which we hypothesize will be reduced from 35% to 28% with ANH. Secondary outcomes are all-cause 30-day mortality, acute kidney injury, bleeding complications, and ischemic complications.

CONCLUSION

The trial is designed to determine whether ANH can safely reduce RBC transfusion after elective cardiac surgery with CPB.

STUDY REGISTRATION

This trial was registered on ClinicalTrials.gov in April 2019 with the trial identification number NCT03913481.

Safety and Tolerability of Continuous Inhaled Iloprost Therapy for Severe Pulmonary Hypertension in Neonates and Infants

This is a single-center retrospective study to assess the safety and tolerability of continuous inhaled iloprost use as rescue therapy for refractory pulmonary hypertension (PH) in critically ill neonates and infants. A retrospective chart review was performed on 58 infants and data were collected at baseline, 1, 6, 12, 24, 48 and 72 h of iloprost initiation. Primary outcomes were change in heart rate (HR), fraction of inspired oxygen (FiO2), mean airway pressures (MAP), blood pressure (BP) and oxygenation index (OI). Secondary outcomes were need for extracorporeal membrane oxygenation (ECMO) and death. 51 patients treated for >6 h were analyzed in 2 age groups, neonate (≤28 days: n = 32) and infant (29-365 days: n = 19). FiO2 (p < 0.001) and OI (p = 0.01) decreased, while there were no significant changes in MAP, BP and HR. Of the fifteen patients placed on ECMO, seven were bridged off ECMO on iloprost and eight died. Twenty-four out of fifty-one patients (47%) recovered without requiring ECMO, while twelve (23%) died. Iloprost as add-on therapy for refractory PH in critically ill infants in the NICU has an acceptable tolerability and safety profile. Large prospective multicenter studies using iloprost in the neonatal ICU are necessary to validate these results.

Impact of Blood Pressure Targets in Patients With Heart Failure Undergoing Postresuscitation Care: A Subgroup Analysis From a Randomized Controlled Trial

BACKGROUND

To assess the effect of targeting higher or lower blood pressure during postresucitation intensive care among comatose patients with out-of-hospital cardiac arrest with a history of heart failure.

METHODS

The BOX trial (Blood Pressure and Oxygenation Targets After Out-of-Hospital Cardiac Arrest) was a randomized, controlled, double-blinded, multicenter study comparing titration of vasopressors toward a mean arterial pressure (MAP) of 63 versus 77 mm Hg during postresuscitation intensive care. Patients with a history of heart failure were included in this substudy. Pulmonary artery catheters were inserted shortly after admission. History of heart failure was assessed through chart review of all included patients. The primary outcome was cardiac index during the first 72 hours. Secondary outcomes were left ventricular ejection fraction, heart rate, stroke volume, renal replacement therapy and all-cause mortality at 365 days.

RESULTS

A total of 134 patients (17% of the BOX cohort) had a history of heart failure (patients with left ventricular ejection fraction, ≤40%: 103 [77%]) of which 71 (53%) were allocated to a MAP of 77 mm Hg. Cardiac index at intensive care unit arrival was 1.77±0.11 L/min·m-2 in the MAP63-group and 1.78±0.17 L/min·m-2 in the MAP77, P=0.92. During the next 72 hours, the mean difference was 0.15 (95% CI, -0.04 to 0.35) L/min·m-2; Pgroup=0.22. Left ventricular ejection fraction and stroke volume was similar between the groups. Patients allocated to MAP77 had significantly elevated heart rate (mean difference 6 [1-12] beats/min, Pgroup=0.03). Vasopressor usage was also significantly increased (P=0.006). At 365 days, 69 (51%) of the patients had died. The adjusted hazard ratio for 365 day mortality was 1.38 (0.84-2.27), P=0.20 and adjusted odds ratio for renal replacement therapy was 2.73 (0.84-8.89; P=0.09).

CONCLUSIONS

In resuscitated patients with out-of-hospital cardiac arrest with a history of heart failure, allocation to a higher blood pressure target resulted in significantly increased heart rate in the higher blood pressure-target group. However, no certain differences was found for cardiac index, left ventricular ejection fraction or stroke volume.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03141099.

Norepinephrine dosing in France: Time to move forward!

Norepinephrine is the first-line vasopressor used in acute cardio-circulatory failure. At the bedside, its dose is critical as it serves to determine the severity of patients, to compare the patients between different studies, and to start specific interventions. Recently, several investigators underlined differences in the expression of norepinephrine doses according to countries and manufacturers. For various reasons, all norepinephrine products are processed to a salt formulation thereby generating a stable and soluble conjugated acid in a slightly acidic solution. Depending on the salt used, the total weight will differ, but the weight of pure norepinephrine base is the same. This results in at-risk situations with large variations in terms of practices, evaluation and treatment. In this technical note, we summarized the evidence and provided a few suggestions to improve the practices at different levels.

The interaction of net ultrafiltration rate with urine output and fluid balance after continuous renal replacement therapy initiation: A multi-Centre study

PURPOSE

During continuous renal replacement therapy (CRRT), a high net ultrafiltration rate (NUF) may worsen the decrease in urine output (UO) associated with starting CRRT. However, fluid balance (FB) may modulate this association. We aimed to examine the relationship between NUF, UO and FB at the start of CRRT.

METHODS

A retrospective cohort study of 1030 CRRT-treated patients admitted to two tertiary ICUs.

RESULTS

Median age was 60 years (IQR, 48-70), median APACHE III was 94 (IQR, 76-114) and median NUF rate was 0.7 mL/kg/h. In the 24 h after CRRT started, the mean hourly UO decreased from 25.5 mL to 11.9 mL (P < 0.001). Moreover, after adjusting for multiple confounders on multivariable analysis, a higher NUF was not significantly associated with a lower UO (-1.5 mL/kg for every 1 mL/kg/h increase in NUF; 95% CI -3.1 to 0.04; p = 0.064). In addition, pre-CRRT FB did not modulate the above relationship between higher NUF and lower UO.

CONCLUSION

A higher NUF rate was not significantly associated with a greater immediate and sustained reduction in UO after CRRT commencement. FB before CRRT was also not associated with a greater reduction in UO. These findings do not provide evidence for an effect of NUF on renal function.

Implementation of Society for Cardiovascular Angiography and Interventions classification in patients with cardiogenic shock secondary to acute myocardial infarction in a spanish university hospital

BACKGROUND

Killip-Kimball classification has been used for estimating death risk in patients suffering acute myocardial infarction (AMI). Killip-Kimball stage IV corresponds to cardiogenic shock. However, the Society for Cardiovascular Angiography and Interventions (SCAI) classification provides a more precise tool to classify patients according to shock severity. The aim of this study was to apply this classification to a cohort of Killip IV patients and to analyze the differences in death risk estimation between the two classifications.

METHODS

A single-center retrospective cohort study of 100 consecutive patients hospitalized for "Killip IV AMI" between 2016 and 2023 was performed to reclassify patients according to SCAI stage.

RESULTS

Distribution of patients according to SCAI stages was B=4%, C=53%, D=27%, E=16%. Thirty-day mortality increased progressively according to these stages (B=0%, C=11.88%, D=55.56%, E=87.50%; P<0.001). The exclusive use of Killip IV stage overestimated death risk compared to SCAI C (35% vs. 11.88%, P=0.002) and underestimated it compared to SCAI D and E stages (35% vs. 55.56% and 87.50%, P=0.03 and P<0.001, respectively). Age >69 years, creatinine >1.15 mg/dl and advanced SCAI stages (SCAI D and E) were independent predictors of 30-day mortality. Mechanical circulatory support use showed an almost significant benefit in advanced SCAI stages (D and E hazard ratio, 0.45; 95% confidence interval, 0.19-1.06; P=0.058).

CONCLUSIONS

SCAI classification showed superior death risk estimation compared to Killip IV. Age, creatinine levels and advanced SCAI stages were independent predictors of 30-day mortality. Mechanical circulatory support could play a beneficial role in advanced SCAI stages.

A service evaluation of measuring fluid responsiveness in acutely unwell hypotensive patients outside of critical care

INTRODUCTION

Early recognition and prompt, appropriate management may reduce mortality in patients with sepsis. The Surviving Sepsis Campaign's guidelines suggest the use of dynamic measurements to guide fluid resuscitation in sepsis; although these methods are rarely employed to monitor cardiac output in response to fluid administration outside intensive care units. This service evaluation investigated the introduction of a nurse led protocolised goal-directed fluid management using a non-invasive cardiac output monitor to the standard assessment of hypotensive ward patients.

METHODS

We introduced the use of a goal-directed fluid management protocol into our critical care outreach teams' standard clinical assessment. Forty-nine sequential patients before and thirty-nine after its introduction were included in the assessment.

RESULTS

Patients in the post-intervention cohort received less fluid in the 6 h following outreach assessment (750mls vs 1200mls). There were no differences in clinical background or rates of renal replacement therapy, but rates of invasive and non-invasive ventilation were reduced (0% vs 31%). Although the groups were similar, the post-intervention patients had lower recorded blood pressures.

CONCLUSION

IV fluid therapy in the patient with hypotension complicating sepsis can be challenging. Excessive IV fluid administration is commonplace and associated with harm, and the use of advanced non-invasive haemodynamic monitoring by trained nurses can provide objective evaluation of individualised response to treatment. Avoiding excessive IV fluid and earlier institution of appropriate vasopressor therapy may improve patient outcomes.

IMPLICATIONS FOR CLINICAL PRACTICE

Adoption of dynamic measures of cardiac output outside of critical care by trained critical care nurses is feasible and may translate into improved patient outcomes. In hospitals with a nurse-led critical care outreach service, consideration should be given to such an approach.

Biventricular function in preterm infants with patent ductus arteriosus ligation: A three-dimensional echocardiographic study

BACKGROUND

The detailed hemodynamics after patent ductus arteriosus (PDA) ligation in preterm infants remain unknown. We aimed to clarify the effect of surgical ligation on left ventricular (LV) and right ventricular (RV) volume and function.

METHODS

Echocardiography was performed in 41 preterm infants (median gestational age: 25 weeks) before and after PDA ligation. Global longitudinal strain was determined using three-dimensional speckle-tracking echocardiography. These values were compared with those in 36 preterm infants without PDA (non-PDA).

RESULTS

Preoperatively, the PDA group had greater end-diastolic volume (EDV) and cardiac output (CO) in both ventricles, a higher LV ejection fraction (LVEF) (53% vs 44%) and LV global longitudinal strain, and a lower RVEF (47% vs 52%) than the non-PDA group. At 4-8 h postoperatively, the two groups had a similar LVEDV and RVEDV. However, the PDA group had a lower EF and CO in both ventricles than the non-PDA group. At 24-48 h postoperatively, the RVEF was increased, but the LVEF remained decreased, and LVCO was increased.

CONCLUSIONS

PDA induces biventricular loading and functional abnormalities in preterm infants, and they dramatically change after surgery. Three-dimensional echocardiography may be beneficial to understand the status of both ventricles.

IMPACT

Preterm infants are at high risk of hemodynamic compromise following a sudden change in loading conditions after PDA ligation. Three-dimensional echocardiography enables quantitative and serial evaluation of ventricular function and volume in preterm infants with PDA. PDA induces biventricular loading and functional abnormalities in preterm infants, and they dramatically change after surgery.

Blood Pressure Management for Hypotensive Patients in Intensive Care and Perioperative Cardiovascular Settings

Blood pressure is a critical physiological parameter, particularly in the context of cardiac intensive care and perioperative settings. As a primary indicator of organ perfusion, the maintenance of adequate blood pressure is imperative for the assurance of sufficient tissue oxygen delivery. Among critically ill and major surgery patients, the continuous monitoring of blood pressure is performed as a standard practice for patients. Nonetheless, uncertainties remain regarding blood pressure goals, and there is no consensus regarding blood pressure targets. This review describes the determinants of blood pressure, examine the influence of blood pressure on organ perfusion, and synthesize the current clinical evidence from various intensive care and perioperative settings to provide a concise guidance for daily clinical practice.

Tracheostomy is associated with decreased vasoactive-inotropic score in postoperative cardiac surgery patients on prolonged mechanical ventilation

Objective

We sought to quantify the influence that tracheostomy placement has on the hemodynamic stability of postoperative cardiac surgery patients with persistent ventilatory requirements.

Methods

A retrospective, single-center, and observational analysis of postoperative cardiac surgery patients with prolonged mechanical ventilation who underwent tracheostomy placement from 2018 to 2022 was conducted. Patients were excluded if receiving mechanical circulatory support or if they had an unrelated significant complication 3 days surrounding tracheostomy placement. Vasoactive and inotropic requirements were quantified using the Vasoactive-Inotrope Score.

Results

Sixty-one patients were identified, of whom 58 met inclusion criteria. The median vasoactive-inotrope score over the 3 days before tracheostomy compared with 3 days after decreased from 3.35 days (interquartile range, 0-8.79) to 0 days (interquartile range, 0-7.79 days) (P = .027). Graphic representation of this trend demonstrates a clear inflection point at the time of tracheostomy. Also, after tracheostomy placement, fewer patients were on vasoactive/inotropic infusions (67.2% [n = 39] pre vs 24.1% [n = 14] post; P < .001) and sedative infusions (62.1% [n = 36] pre vs 27.6% [n = 16] post; P < .001). The percent of patients on active mechanical ventilation did not differ.

Conclusions

The median vasoactive-inotrope score in cardiac surgery patients with prolonged mechanical ventilation was significantly reduced after tracheostomy placement. There was also a significant reduction in the number of patients on vasoactive/inotropic and sedative infusions 3 days after tracheostomy. These data suggest that tracheostomy has a positive effect on the hemodynamic stability of patients after cardiac surgery and should be considered to facilitate postoperative recovery.

Intraoperative renal replacement therapy during liver transplantation in children: Safety, efficacy and impact on survival

BACKGROUND

Intraoperative Continuous Renal Replacement Therapy (iCRRT) can prevent life-threatening complications, facilitate fluid management, and maintain metabolic homeostasis during liver transplantation (LT) in adults. There is a paucity of data in pediatric LT. We evaluated the safety, efficacy, and impact on survival of iCRRT in pediatric LT.

METHODS

We conducted a retrospective cohort study of all children requiring CRRT pre-OLT at a quaternary children's hospital from 2014 to 2022. Demographic characteristics, intraoperative events, and post-LT outcomes were compared between those who received iCRRT and those who did not.

RESULTS

Out of 306 patients who received LT, 30 (10%) were supported with CRRT at least 24 h prior to LT, of which 11 (36%) received iCRRT. The two cohorts were similar in demographics, diagnosis of liver disease, and severity of illness. The iCRRT patients experienced massive blood loss and increased transfusion requirements. There was no difference in intraoperative metabolic balance. One-year post-LT mortality rates were similar.

CONCLUSION

ICRRT is safe in critically ill children with pre-LT renal dysfunction. It optimizes fluid and blood product resuscitation while maintaining metabolic homeostasis. Candidates need to be carefully chosen for this highly resource-intensive therapy to benefit this fragile population.

Dose equivalence for metaraminol and noradrenaline - A retrospective analysis

BACKGROUND

Noradrenaline and metaraminol are commonly used vasopressors in critically ill patients. However, little is known of their dose equivalence.

METHODS

We conducted a single centre retrospective cohort study of all ICU patients who transitioned from metaraminol to noradrenaline infusions between August 26, 2016 and December 31, 2020. Patients receiving additional vasoactive drug infusion were excluded. Dose equivalence was calculated based on the last hour metaraminol dose (in μg/min) and the first hour noradrenaline dose (in μg/min) with the closest matched mean arterial pressure (MAP). Sensitivity analyses were performed on patients with acute kidney injury (AKI), sepsis and mechanical ventilation.

RESULTS

We studied 195 patients. The median conversion ratio of metaraminol to noradrenaline was 12.5:1 (IQR 7.5-20.0) for the overall cohort. However, the coefficient of variation was 77% and standard deviation was 11.8. Conversion ratios were unaffected by sepsis or mechanical ventilation but increased (14:1) with AKI. One in five patients had a MAP decrease of >10 mmHg during the transition period from metaraminol to noradrenaline. Post-transition noradrenaline dose (p < 0.001) and AKI (p = 0.045) were independently associated with metaraminol dose. The proportion of variation in noradrenaline dose predicted from metaraminol dose was low (R2 = 0.545).

CONCLUSIONS

The median dose equivalence for metaraminol and noradrenaline in this study was 12.5:1. However, there was significant variance in dose equivalence, only half the proportion of variation in noradrenaline infusion dose was predicted by metaraminol dose, and conversion-associated hypotension was common.

Acute right ventricular geometric change predicts outcomes in HeartMate 3 patients

BACKGROUND

The physiological response of the right ventricle (RV) following left ventricular assist device (LVAD) implantation is difficult to predict. We aimed to investigate RV geometric and functional changes after LVAD insertion and their effects on clinical outcomes.

METHODS

We retrospectively reviewed 188 patients who underwent HeartMate 3 implantation at our center between November 2014 and September 2021. The RV end-diastolic diameter (RVEDD) and RV end-diastolic area (RVEDA) were measured on preoperative and predischarge transthoracic echocardiography. The nonadapted group included patients with increased RVEDD and RVEDA at discharge. The composite outcome was defined as death or readmission due to worsening right heart failure.

RESULTS

There were 82 patients (44%) who had a nonadapted and 106 patients (56%) who had an adapted RV. Preoperatively, the nonadapted group had smaller RVEDD (46 vs 49 mm, p < 0.001) and RVEDA (27 vs 31 cm2, p < 0.001). At discharge, the nonadapted group had larger RVEDD (51 vs 43 mm, p < 0.001) and RVEDA (33 vs 27 cm2, p < 0.001). Kaplan-Meier analysis demonstrated worse 3-year survival (77% vs 91%, p = 0.006) and freedom from composite outcome (58% vs 85%, p < 0.001) in the nonadapted group. A multivariable Cox proportional hazards model showed that nonadaption (hazard ratio [HR] 3.09, 95% confidence interval [CI] 1.29-7.40, p = 0.01) and age (HR 3.73, 95% CI 1.42-9.77, p = 0.007) were independent predictors of composite outcome.

CONCLUSIONS

Acute RV dimensional changes after LVAD insertion may represent intrinsic RV function and may be a useful prognostic marker.

The Utility of Risk Scores in Postcardiotomy Extracorporeal Membrane Oxygenation

BACKGROUND

The use of a venoarterial extracorporeal membrane oxygenation (ECMO) in the postcardiotomy shock setting (PC-ECMO) can be life-saving. Risk stratification for patients under PC-ECMO is currently challenging. The aim of this study was to assess the discriminatory ability of the different available risk scores for mortality in PC-ECMO patients.

METHODS

Patients aged >18 years undergoing coronary artery bypass, valve surgery, or a combination of these procedures and implanted an ECMO for postcardiotomy shock between January 2017 and June 2022 in a single ELSO registered center were retrospectively included. The STS, Euroscore II, SAVE, modified SAVE, APACHE II, and VIS scores were compared for their discriminatory ability concerning weaning and 30-day survival.

RESULTS

During the study period, 7342 patients underwent coronary bypass or valve surgery, of whom 109 patients with PC-ECMO were included in the analysis. The Euroscore II and STS scores were not associated significantly with 30-day mortality, whereas the SAVE, the modified SAVE, APACHE II, and VIS scores significantly predicted 30-day mortality. The SAVE and the modified SAVE scores showed moderate discrimination ability with AUCs of 0.672 and 0.695, while the APACHE and VIS scores had a satisfactory discriminatory ability with AUCs of 0.727 and 0.844, respectively.

CONCLUSION

Currently used risk scores for PC-ECMO patients do not provide satisfactory predictions for weaning and survival. VIS at the 24th hour can be a valuable parameter for risk analysis and prospective studies can investigate novel PC-ECMO risk scoring systems.

Morning or Afternoon Scheduling for Elective Coronary Artery Bypass Surgery: Influence of Longer Fasting Periods from Metabolic and Hemodynamic Perspectives

BACKGROUND

Prolonged preoperative fasting may worsen postoperative outcomes. Cardiac surgery has higher perioperative risk, and longer fasting periods may be not well-tolerated. We analysed the postoperative metabolic and hemodynamic variables in patients undergoing elective coronary artery bypass grafting (CABG) according to their morning or afternoon schedule.

METHODS

Single-centre retrospective study at University teaching hospital (1-year data collection from electronic medical records). Using a mixed-effects linear regression model adjusted for several covariates, we compared metabolic (lactatemia, pH, and base deficit [BD]) and haemodynamic values (patients on vasoactive support, and vasoactive inotropic score [VIS]) at 7 prespecified time-points (admission to intensive care, and 1st, 3rd, 6th, 12th, 18th, and 24th postoperative hours).

RESULTS

339 patients (n = 176 morning, n = 163 afternoon) were included. Arterial lactatemia and BD were similar (overall P = 0.11 and P = 0.84, respectively), while pH was significantly lower in the morning group (overall P < 0.05; mean difference -0.01). Postoperative urine output, fluid balance, mean arterial pressure, and central venous pressure were similar (P = 0.59, P = 0.96, P = 0.58 and P = 0.53, respectively). A subgroup analysis of patients with diabetes (n = 54 morning, n = 45 afternoon) confirmed the same findings. The VIS values and the proportion of patients on vasoactive support was higher in the morning cases at the 18th (P = 0.002 and p=0.04, respectively) and 24th postoperative hours (P = 0.003 and P = 0.04, respectively). Mean intensive care length of stay was 1.94 ± 1.36 days versus 2.48 ± 2.72 days for the afternoon and morning cases, respectively (P = 0.02).

CONCLUSIONS

Patients undergoing elective CABG showed similar or better metabolic and hemodynamic profiles when scheduled for afternoon surgery.

Temporary extracorporeal life support: single-centre experience with a new concept

OBJECTIVES

The combination of veno-arterial extracorporeal membrane oxygenation with a micro-axial flow pump (ECMELLA) is increasingly used for cardiogenic shock (CS) therapy. We report our experience with a novel single-artery access ECMELLA setup with either femoral (2.0) or jugular venous cannulation (2.1), respectively.

METHODS

Data from 67 consecutive CS patients treated with ECMELLA 2.0 (n = 56) and 2.1 (n = 11) from December 2020 and December 2022 in a tertiary cardiac center were retrospectively analyzed.

RESULTS

The mean age was 60.7 ± 11 years, 56 patients (84%) were male. CS aetiology was acute on chronic heart failure (n = 35, 52%), myocardial infarction (n = 13, 19.5%), postcardiotomy syndrome (n = 16, 24%) and myocarditis (n = 3, 4.5%). Preoperatively 31 patients (46%) were resuscitated, 53 (79%) were on a ventilator and 60 (90%) were on inotropic support. The median vasoactive inotropic score was 32, and the mean arterial lactate was 8.1 mmol/l. In 39 patients (58%), veno-arterial extracorporeal membrane oxygenation was explanted after a median ECMELLA support of 4 days. Myocardial recovery was achieved in 18 patients (27%), transition to a durable left ventricular assist device in 16 (24%). Thirty-three patients (n = 33; 49%) died on support (25 on ECMELLA and 8 on Impella after de-escalation), 9 (13%) of whom were palliated. Axillary access site bleeding occurred in 9 patients (13.5%), upper limb ischaemia requiring surgical revision in 3 (4.5%). Axillary site infection occurred in 6 cases (9%), and perioperative stroke in 10 (15%; 6 hemorrhagic, 4 thromboembolic).

CONCLUSIONS

ECMELLA 2.0/2.1 is a feasible and effective therapy for severe CS. The single-artery cannulation technique is associated with a relatively low rate of access-related complications.

Amino acids to prevent cardiac surgery-associated acute kidney injury: a randomized controlled trial

BACKGROUND

This study aimed to examine the preventive effect of amino acids on postoperative acute kidney injury (AKI).

METHODS

This was single-center, patient- and assessor-blinded, randomized controlled trial. Patients who underwent aortic surgery with cardiopulmonary bypass were included. The intervention group received 60 g/day of amino acids for up to 3 days. The control group received standard care. The primary outcome was the incidence of AKI. We assessed the effect of amino acids on AKI using a Cox proportional hazards regression model.

RESULTS

Sixty-six patients were randomly assigned to the control or intervention group. One patient in the control group withdrew consent after randomization. The incidence of AKI was 10 patients (30.3%) in the intervention group versus 18 patients (56.2%) in the control group (adjusted hazard ratio, 0.44; 95% confidence interval, 0.20-0.95; P = 0.04).

CONCLUSIONS

This trial demonstrated a significant reduction in AKI incidence with amino acid supplementation.

TRIAL REGISTRATION

jRCT, jRCTs051210154. Registered 31 December 2021, https://jrct.niph.go.jp/re/reports/detail/69916.

Physiological changes after fluid bolus therapy in cardiac surgery patients: A propensity score matched case-control study

Objective

Fluid bolus therapy (FBT) is ubiquitous in intensive care units (ICUs) after cardiac surgery. However, its physiological effects remain unclear.

Design

: We performed an electronic health record-based quasi-experimental ICU study after cardiac surgery. We applied propensity score matching and compared the physiological changes after FBT episodes to matched control episodes where despite equivalent physiology no fluid bolus was given.

Setting

The study was conducted in a multidisciplinary ICU of a tertiary-level academic hospital.

Participants

The study included 2,736 patients who underwent Coronary Artery Bypass Grafting and/or heart valve surgery.

Main Outcome Measures

Changes in cardiac output (CO) and mean arterial pressure (MAP) during the 60 minutes following FBT.

Results

We analysed 3572 matched fluid bolus (FB) episodes. After FBT, but not in control episodes, CO increased within 10 min, with a maximum increase of 0.2 l/min (95%CI 0.1 to 0.2) or 4% above baseline at 40 min (p < 0.0001 vs. controls). CO increased by > 10% from baseline in 60.6% of FBT and 49.1% of control episodes (p < 0.0001). MAP increased by > 10% in 51.7% of FB episodes compared to 53.4% of controls. Finally, FBT was not associated with changes in acid-base status or oxygen delivery.

Conclusion

In this quasi-experimental comparative ICU study in cardiac surgery patients, FBT was associated with statistically significant but numerically small increases in CO. Nearly half of FBT failed to induce a positive CO or MAP response.

Should the Vasoactive Inotropic Score be a Determinant for Early Initiation of VA ECMO in Postcardiotomy Cardiogenic Shock?

OBJECTIVES

The authors investigated the role of early venoarterial extracorporeal membrane oxygenation (VA ECMO) implantation in patients with postcardiotomy cardiogenic shock (PCS) on mortality and morbidity when integrating vasoactive-inotropic score (VIS) and type of catecholamine support.

DESIGN

A retrospective, multicenter, observational study with propensity-weight matching.

SETTING

Four university-affiliated intensive care units.

PARTICIPANTS

Patients with PCS in the operating room.

INTERVENTIONS

Early VA ECMO support.

MEASUREMENTS AND MAIN RESULTS

Of 2,742 patients screened during the study period, 424 (16%) patients were treated with inotropic drugs, and 75 (3%) patients were supported by VA ECMO in the operating room. Patients supported by VA ECMO had a higher use of vasopressor and inotropic drugs, with a higher VIS score. After propensity matching (integrating VIS and catecholamines type), mortality (56% v 20%, p < 0.001) and morbidity (cardiac, renal, transfusion) were higher in patients supported by VA ECMO than in a matched control group.

CONCLUSIONS

When matching integrated the pre-ECMO VIS and the type of catecholamines, VA ECMO remained associated with high mortality and morbidity, suggesting that VIS alone should not be used as a main determinant of VA ECMO implantation.

Evaluation of the Renal Angina Index to Predict the Development of Acute Kidney Injury in Children With Sepsis Who Live in Middle-Income Countries

OBJECTIVE

The renal angina index (RAI) provides a clinically feasible and applicable tool to identify critically ill children at risk of severe acute kidney injury (AKI) in high-income countries. Our objective was to evaluate the performance of the RAI as a predictor of the development of AKI in children with sepsis in a middle-income country and its association with unfavorable outcomes.

METHODS

This is a retrospective cohort study in children with sepsis hospitalized in the pediatric intensive care unit (PICU) between January 2016 and January 2020. The RAI was calculated 12 hours after admission to predict the development of AKI and at 72 hours to explore its association with mortality, the need for renal support therapy, and PICU stay.

RESULTS

We included 209 PICU patients with sepsis with a median age of 23 months (interquartile range, 7-60). We found that 41.1% of the cases (86/209) developed de novo AKI on the third day of admission (KDIGO 1, 24.9%; KDIGO 2, 12.9%; and KDIGO 3, 3.3%).Overall mortality was 8.1% (17/209), higher in patients with AKI (7.7% vs 0.5%, P < 0.01). The RAI on admission was able to predict the presence of AKI on day 3 (area under the curve (AUC), 0.87; sensitivity, 94.2%; specificity, 100%; P < 0.01), with a negative predictive value greater than 95%. An RAI greater than 8 at 72 hours was associated with a greater risk of mortality (adjusted odds ratio [aOR], 2.6; 95% confidence interval [CI], 2.0-3.2; P < 0.01), a need for renal support therapy (aOR, 2.9; 95% CI, 2.3-3.6; P < 0.01), and a PICU stay of more than 10 days (aOR, 1.54; 95% CI, 1.1-2.1; P < 0.01).

CONCLUSIONS

The RAI on the day of admission is a reliable and accurate tool for predicting the risk of developing AKI on day 3, in critically ill children with sepsis in a limited resource context. A score greater than eight 72 hours after admission is associated with a higher risk of death, the need for renal support therapy, and PICU stay.

Feasibility and Safety of Sildenafil to Repair Brain Injury Secondary to Birth Asphyxia (SANE-01): A Randomized, Double-blind, Placebo-controlled Phase Ib Clinical Trial

OBJECTIVE

To test feasibility and safety of administering sildenafil in neonates with neonatal encephalopathy (NE), developing brain injury despite therapeutic hypothermia (TH).

STUDY DESIGN

We performed a randomized, double-blind, placebo-controlled phase Ib clinical trial between 2016 and 2019 in neonates with moderate or severe NE, displaying brain injury on day-2 magnetic resonance imaging (MRI) despite TH. Neonates were randomized (2:1) to 7-day sildenafil or placebo (2 mg/kg/dose enterally every 12 hours, 14 doses). Outcomes included feasibility and safety (primary outcomes), pharmacokinetics (secondary), and day-30 neuroimaging and 18-month neurodevelopment assessments (exploratory).

RESULTS

Of the 24 enrolled neonates, 8 were randomized to sildenafil and 3 to placebo. A mild decrease in blood pressure was reported in 2 of the 8 neonates after initial dose, but not with subsequent doses. Sildenafil plasma steady-state concentration was rapidly reached, but decreased after TH discontinuation. Twelve percent of neonates (1/8) neonates died in the sildenafil group and 0% (0/3) in the placebo group. Among surviving neonates, partial recovery of injury, fewer cystic lesions, and less brain volume loss on day-30 magnetic resonance imaging were noted in 71% (5/7) of the sildenafil group and in 0% (0/3) of the placebo group. The rate of death or survival to 18 months with severe neurodevelopmental impairment was 57% (4/7) in the sildenafil group and 100% (3/3) in the placebo group.

CONCLUSIONS

Sildenafil was safe and well-absorbed in neonates with NE treated with TH. Optimal dosing needs to be established. Evaluation of a larger number of neonates through subsequent phases II and III trials is required to establish efficacy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.govNCT02812433.

Organ perfusion pressure at admission and clinical outcomes in patients hospitalized for acute heart failure

AIMS

Hypoperfusion portends adverse outcomes in acute heart failure (AHF). The gradient between end-organ inflow and outflow pressures may more closely reflect hypoperfusion than mean arterial pressure (MAP) alone. The aim of this study was to investigate organ perfusion pressure (OPP), calculated as MAP minus central venous pressure (CVP), as a prognostic marker in AHF.

METHODS AND RESULTS

The Sodium NItroPrusside Treatment in Acute Heart Failure (SNIP)-AHF study was a multicentre retrospective cohort study of 200 consecutive patients hospitalized for AHF treated with sodium nitroprusside. Only patients with both MAP and invasive CVP data available from the SNIP-AHF cohort were included in this analysis. The primary endpoint was to assess OPP as a predictor of worsening heart failure (WHF), defined as the worsening of signs and symptoms of heart failure leading to intensification of therapy at 48 h. One hundred and forty-six patients fulfilling the inclusion criteria were included [mean age: 61.1 ± 13.5 years, 32 (21.9%) females; mean body mass index: 26.2 ± 11.7 kg/m2; mean left ventricular ejection fraction: 23.8%±11.4%, mean MAP: 80.2 ± 13.2 mmHg, and mean CVP: 14.0 ± 6.1 mmHg]. WHF occurred in 14 (9.6%) patients. At multivariable models including hemodynamic variables (OPP, shock index, and CVP), OPP at admission was the best predictor of WHF at 48 h [OR 0.91 (95% confidence interval 0.86-0.96), P-value = 0.001] with an optimal cut-off value of 67.5 mmHg (specificity 47.3%, sensitivity 100%, and AUC 0.784 ± 0.054). In multivariable models, including univariable significant parameters available at first bedside assessment, namely New York Heart Association functional class, OPP, shock index, CVP, and left ventricular end-diastolic diameter, OPP consistently and significantly predicted WHF at 48 h.

CONCLUSION

In this retrospective analysis on patients hospitalized for AHF treated with sodium nitroprusside, on-admission OPP significantly predicted WHF at 48 h with high sensitivity.

Severe Lung Dysfunction and Pulmonary Blood Flow during Extracorporeal Membrane Oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is indicated for patients with severe respiratory and/or circulatory failure. The standard technique to visualize the extent of pulmonary damage during ECMO is computed tomography (CT).

PURPOSE

This single-center, retrospective study investigated whether pulmonary blood flow (PBF) measured with echocardiography can assist in assessing the extent of pulmonary damage and whether echocardiography and CT findings are associated with patient outcomes.

METHODS

All patients (>15 years) commenced on ECMO between 2011 and 2017 with septic shock of pulmonary origin and a treatment time >28 days were screened. Of 277 eligible patients, 9 were identified where both CT and echocardiography had been consecutively performed.

RESULTS

CT failed to indicate any differences in viable lung parenchyma within or between survivors and non-survivors at any time during ECMO treatment. Upon initiation of ECMO, the survivors (n = 5) and non-survivors (n = 4) had similar PBF. During a full course of ECMO support, survivors showed no change in PBF (3.8 ± 2.1 at ECMO start vs. 7.9 ± 4.3 L/min, p = 0.12), whereas non-survivors significantly deteriorated in PBF from 3.5 ± 1.0 to 1.0 ± 1.1 L/min (p = 0.029). Tidal volumes were significantly lower over time among the non-survivors, p = 0.047.

CONCLUSIONS

In prolonged ECMO for pulmonary septic shock, CT was not found to be effective for the evaluation of pulmonary viability or recovery. This hypothesis-generating investigation supports echocardiography as a tool to predict pulmonary recovery via the assessment of PBF at the early to later stages of ECMO support.

Effects of ketone body 3-hydroxybutyrate on cardiac and mitochondrial function during donation after circulatory death heart transplantation

Normothermic regional perfusion (NRP) allows assessment of therapeutic interventions prior to donation after circulatory death transplantation. Sodium-3-hydroxybutyrate (3-OHB) increases cardiac output in heart failure patients and diminishes ischemia-reperfusion injury, presumably by improving mitochondrial metabolism. We investigated effects of 3-OHB on cardiac and mitochondrial function in transplanted hearts and in cardiac organoids. Donor pigs (n = 14) underwent circulatory death followed by NRP. Following static cold storage, hearts were transplanted into recipient pigs. 3-OHB or Ringer's acetate infusions were initiated during NRP and after transplantation. We evaluated hemodynamics and mitochondrial function. 3-OHB mediated effects on contractility, relaxation, calcium, and conduction were tested in cardiac organoids from human pluripotent stem cells. Following NRP, 3-OHB increased cardiac output (P < 0.0001) by increasing stroke volume (P = 0.006), dP/dt (P = 0.02) and reducing arterial elastance (P = 0.02). Following transplantation, infusion of 3-OHB maintained mitochondrial respiration (P = 0.009) but caused inotropy-resistant vasoplegia that prevented weaning. In cardiac organoids, 3-OHB increased contraction amplitude (P = 0.002) and shortened contraction duration (P = 0.013) without affecting calcium handling or conduction velocity. 3-OHB had beneficial cardiac effects and may have a potential to secure cardiac function during heart transplantation. Further studies are needed to optimize administration practice in donors and recipients and to validate the effect on mitochondrial function.

The association of vasoactive-inotropic score and surgical patients' outcomes: a systematic review and meta-analysis

BACKGROUND

The objective of this study is to conduct a systematic review and meta-analysis examining the relationship between the vasoactive-inotropic score (VIS) and patient outcomes in surgical settings.

METHODS

Two independent reviewers searched PubMed, Web of Science, EMBASE, Scopus, Cochrane Library, Google Scholar, and CNKI databases from November 2010, when the VIS was first published, to December 2022. Additional studies were identified through hand-searching the reference lists of included studies. Eligible studies were those published in English that evaluated the association between the VIS and short- or long-term patient outcomes in both pediatric and adult surgical patients. Meta-analysis was performed using RevMan Manager version 5.3, and quality assessment followed the Joanna Briggs Institute (JBI) Critical Appraisal Checklists.

RESULTS

A total of 58 studies comprising 29,920 patients were included in the systematic review, 34 of which were eligible for meta-analysis. Early postoperative VIS was found to be associated with prolonged mechanical ventilation (OR 5.20, 95% CI 3.78-7.16), mortality (OR 1.08, 95% CI 1.05-1.12), acute kidney injury (AKI) (OR 1.26, 95% CI 1.13-1.41), poor outcomes (OR 1.02, 95% CI 1.01-1.04), and length of stay (LOS) in the ICU (OR 3.50, 95% CI 2.25-5.44). The optimal cutoff value for the VIS as an outcome predictor varied between studies, ranging from 10 to 30.

CONCLUSION

Elevated early postoperative VIS is associated with various adverse outcomes, including acute kidney injury (AKI), mechanical ventilation duration, mortality, poor outcomes, and length of stay (LOS) in the ICU. Monitoring the VIS upon return to the Intensive Care Unit (ICU) could assist medical teams in risk stratification, targeted interventions, and parent counseling.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022359100.

Cardiac Arrest-Associated Coagulopathy Could Predict 30-day Mortality: A Retrospective Study from Medical Information Mart for Intensive Care IV Database

BACKGROUND

Cardiac arrest (CA) can activate the coagulation system. Some coagulation-related indicators are associated with clinical outcomes. Early evaluation of patients with cardiac arrest-associated coagulopathy (CAAC) not only predicts clinical outcomes, but also allows for timely clinical intervention to prevent disseminated intravascular coagulation.

OBJECTIVE

To assess whether CAAC predicts 30-day cumulative mortality.

METHODS

From the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, we conducted a retrospective cohort study from 2008 to 2019. Based on international normalized ratio (INR) value and platelet count, we diagnosed CAAC cases and made the following stratification of severity: mild CAAC was defined as 1.4 > INR≧1.2 and 100,000/µL < platelet count≦150,000/µL; moderate CAAC was defined with either 1.6 > INR≧1.4 or 80,000/µL < platelet count≦100,000/µL; severe CAAC was defined as an INR≧1.6 and platelet count≦80,000/µL.

RESULTS

A total of 1485 patients were included. Crude survival analysis showed that patients with CAAC had higher mortality risk than those without CAAC (33.0% vs 52.0%, P < 0.001). Unadjusted survival analysis showed an incremental increase in the risk of mortality as the severity of CAAC increased. After adjusting confounders (prehospital characteristics and hospitalization characteristics), CAAC was independently associated with 30-day mortality (hazard rate [HR] 1.77, 95% confidence interval [CI] 1.41-2.25; P < 0.001); moderate CAAC (HR 1.48, 95% CI 1.09-2.10; P = 0.027) and severe CAAC (HR 2.22, 95% CI 1.64-2.97; P < 0.001) were independently associated with 30-day mortality.

CONCLUSION

The presence of CAAC identifies a group of CA at higher risk for mortality, and there is an incremental increase in risk of mortality as the severity of CAAC increases. However, the results of this study should be further verified by multicenter study.

When is the Ideal Time to Calculate the Vasoactive Inotropic Score as a Predictor of Mortality and Morbidity in Cardiac Surgery? A Retrospective Study

INTRODUCTION

The aim of this study was to evaluate the prediction of vasoactive inotropic score (VIS) on early mortality and morbidity after coronary artery bypass grafting (CABG) and to determine the ideal time for score calculation.

MATERIALS AND METHODS

The study included patients who underwent isolated on-pump CABG surgery between November 2021 and November 2022. Pre, intra, and postoperative data were obtained by retrospective chart review. The final VIS value in the operating room (VISintra) and the highest VIS value in the first 24 hours in the intensive care unit (VISmax) were calculated. The patients were divided into two groups; Group 1 who developed early postoperative morbidity and mortality and Group 2 who did not. And the data were analyzed by groups.

RESULTS

A total of 221 patients with a mean age of 63.49 ± 9.96 years were evaluated and 73 (33%) were in Group 1. The cut-off value for VISintra was determined to be 6.20, VISmax was 6,05. VISintra and VISmax values were significantly higher in the poor outcome group. Multivariate analysis showed that only VISmax value was an independent variable on mortality-morbidity.

CONCLUSIONS

Our results imply that the vasoactive inotropic score is an easy and inexpensive score to calculate and can be used as a specific scoring system to predict poor early outcomes in CABG patients. According to statistical analyses, the most predictive time among VIS measurements was VISmax, the highest value calculated in the ICU in the first 24 hours postoperatively.

Identification of Clinically Significant Cytokine Signature Clusters in Patients With Septic Shock

OBJECTIVES

To identify cytokine signature clusters in patients with septic shock.

DESIGN

Prospective observational cohort study.

SETTING

Single academic center in the United States.

PATIENTS

Adult (≥ 18 yr old) patients admitted to the medical ICU with septic shock requiring vasoactive medication support.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred fourteen patients with septic shock completed cytokine measurement at time of enrollment (t 1 ) and 24 hours later (t 2 ). Unsupervised random forest analysis of the change in cytokines over time, defined as delta (t 2 -t 1 ), identified three clusters with distinct cytokine profiles. Patients in cluster 1 had the lowest initial levels of circulating cytokines that decreased over time. Patients in cluster 2 and cluster 3 had higher initial levels that decreased over time in cluster 2 and increased in cluster 3. Patients in clusters 2 and 3 had higher mortality compared with cluster 1 (clusters 1-3: 11% vs 31%; odds ratio [OR], 3.56 [1.10-14.23] vs 54% OR, 9.23 [2.89-37.22]). Cluster 3 was independently associated with in-hospital mortality (hazard ratio, 5.24; p = 0.005) in multivariable analysis. There were no significant differences in initial clinical severity scoring or steroid use between the clusters. Analysis of either t 1 or t 2 cytokine measurements alone or in combination did not reveal clusters with clear clinical significance.

CONCLUSIONS

Longitudinal measurement of cytokine profiles at initiation of vasoactive medications and 24 hours later revealed three distinct cytokine signature clusters that correlated with clinical outcomes.

Intravenous Levothyroxine for Unstable Brain-Dead Heart Donors

BACKGROUND

Hemodynamic instability and myocardial dysfunction are major factors preventing the transplantation of hearts from organ donors after brain death. Intravenous levothyroxine is widely used in donor care, on the basis of observational data suggesting that more organs may be transplanted from donors who receive hormonal supplementation.

METHODS

In this trial involving 15 organ-procurement organizations in the United States, we randomly assigned hemodynamically unstable potential heart donors within 24 hours after declaration of death according to neurologic criteria to open-label infusion of intravenous levothyroxine (30 μg per hour for a minimum of 12 hours) or saline placebo. The primary outcome was transplantation of the donor heart; graft survival at 30 days after transplantation was a prespecified recipient safety outcome. Secondary outcomes included weaning from vasopressor therapy, donor ejection fraction, and number of organs transplanted per donor.

RESULTS

Of the 852 brain-dead donors who underwent randomization, 838 were included in the primary analysis: 419 in the levothyroxine group and 419 in the saline group. Hearts were transplanted from 230 donors (54.9%) in the levothyroxine group and 223 (53.2%) in the saline group (adjusted risk ratio, 1.01; 95% confidence interval [CI], 0.97 to 1.07; P = 0.57). Graft survival at 30 days occurred in 224 hearts (97.4%) transplanted from donors assigned to receive levothyroxine and 213 hearts (95.5%) transplanted from donors assigned to receive saline (difference, 1.9 percentage points; 95% CI, -2.3 to 6.0; P<0.001 for noninferiority at a margin of 6 percentage points). There were no substantial between-group differences in weaning from vasopressor therapy, ejection fraction on echocardiography, or organs transplanted per donor, but more cases of severe hypertension and tachycardia occurred in the levothyroxine group than in the saline group.

CONCLUSIONS

In hemodynamically unstable brain-dead potential heart donors, intravenous levothyroxine infusion did not result in significantly more hearts being transplanted than saline infusion. (Funded by Mid-America Transplant and others; ClinicalTrials.gov number, NCT04415658.).

Myocardial protection with phosphocreatine in high-risk cardiac surgery patients: a randomized trial

BACKGROUND

This study was conducted to test the hypothesis that phosphocreatine (PCr), administered intravenously and as cardioplegia adjuvant in patients undergoing cardiac surgery with prolonged aortic cross clamping and cardiopulmonary bypass (CPB) time, would decrease troponin I concentration after surgery.

METHODS

In this randomized, double-blind, placebo-controlled pilot study we included 120 patients undergoing double/triple valve repair/replacement under cardiopulmonary bypass in the cardiac surgery department of a tertiary hospital. The treatment group received: intravenous administration of 2 g of PCr after anesthesia induction; 2.5 g of PCr in every 1 L of cardioplegic solution (concentration = 10 mmol/L); intravenous administration of 2 g of PCr immediately after heart recovery following aorta declamping; 4 g of PCr at intensive care unit admission. The control group received an equivolume dose of normosaline.

RESULTS

The primary endpoint was peak concentration of troponin I after surgery. Secondary endpoints included peak concentration of serum creatinine, need for, and dosage of inotropic support, number of defibrillations after aortic declamping, incidence of arrhythmias, duration of Intensive Care Unit (ICU) stay, length of hospitalization. There was no difference in peak troponin I concentration after surgery (PCr, 10,508 pg/ml [IQR 6,838-19,034]; placebo, 11,328 pg/ml [IQR 7.660-22.894]; p = 0.24). There were also no differences in median peak serum creatinine (PCr, 100 µmol/L [IQR 85.0-117.0]; placebo, 99.5 µmol/L [IQR 90.0-117.0]; p = 0.87), the number of patients on vasopressor/inotropic agents (PCr, 49 [88%]; placebo, 57 [91%]; p = 0.60), the inotropic score on postoperative day 1 (PCr, 4.0 (0-7); placebo, 4.0 (0-10); p = 0.47), mean SOFA score on postoperative day 1 (PCr, 5.25 ± 2.33; placebo, 5,45 ± 2,65; p = 0.83), need for defibrillation after declamping of aorta (PCr, 22 [39%]; placebo, 25 [40%]; p = 0.9),, duration of ICU stay and length of hospitalization as well as 30-day mortality (PCr, 0 (0%); placebo,1 (4.3%); p = 0.4).

CONCLUSION

PCr administration to patients undergoing double/triple valve surgery under cardiopulmonary bypass is safe but is not associated with a decrease in troponin I concentration. Phosphocreatine had no beneficial effect on clinical outcomes after surgery.

TRIAL REGISTRATION

The study is registered at ClinicalTrials.gov with the Identifier: NCT02757443. First posted (published): 02/05/2016.

Continuous Renal Replacement Therapy and Mortality in Critically Ill Obese Adults

IMPORTANCE

The outcomes of critically ill adults with obesity on continuous renal replacement therapy (CRRT) are poorly characterized. The impact of CRRT dose on these outcomes is uncertain.

OBJECTIVES

This study aimed to determine if obesity conferred a survival advantage for critically ill adults with acute kidney injury (AKI) on CRRT. Secondarily, we evaluated whether the dose of CRRT predicted mortality in this population.

DESIGN SETTING AND PARTICIPANTS

A retrospective, observational cohort study performed at an academic medical center in Minnesota. The study population included critically ill adults with AKI managed with CRRT.

MAIN OUTCOMES AND MEASURES

The primary outcome of 30-day mortality was compared between obese (body mass index [BMI] ≥ 30 kg/m2) and nonobese (BMI < 30 kg/m2) patients. Multivariable regression assessed was used to assess CRRT dose as a predictor of outcomes. An analysis included dose indexed according to actual body weight (ABW), adjusted body weight (AdjBW), or ideal body weight (IBW).

RESULTS

Among 1033 included patients, the median (interquartile range) BMI was 26 kg/m2 (23-28 kg/m2) in the nonobese group and 36 kg/m2 (32-41 kg/m2) in the obese group. Mortality was similar between groups at 30 days (54% vs. 48%; p = 0.06) but lower in the obese group at 90 days (62% vs. 55%; p = 0.02). CRRT dose predicted an increase in mortality when indexed according to ABW or AdjBW (hazard ratio [HR], 1.2-1.16) but not IBW (HR, 1.04).

CONCLUSIONS AND RELEVANCE

In critically ill adults with AKI requiring CRRT, short-term mortality appeared lower in obese patients compared with nonobese patients. Among weight calculations, IBW appears to be preferred to promote safe CRRT dosing in obese patients.

Implementation and effectiveness of a delirium care protocol in Thai critically ill children

BACKGROUND

Delirium in critically ill children can result in long-term morbidity. Our main objectives were to evaluate the effectiveness of a new protocol on the reduction, prevalence, and duration of delirium and to identify associated risk factors.

METHODS

The effectiveness of the protocol was evaluated by a chart review in all critically ill children aged 1 month to 15 years during the study period. A Cornell Assessment of Pediatric Delirium score ≥9 was considered positive for delirium. Data on delirium prevalence and duration from the pre-implementation and post-implementation phases were compared. Univariate and multivariate analyses were used to identify the risk factors of delirium.

RESULTS

A total of 120 children was analyzed (58 children in the pre-implementation group and 62 children in the post-implementation group). Fifty children (41.7%) screened positive for delirium. Age less than 2 years, delayed development, use of mechanical ventilation, and pediatric intensive care unit (PICU) stay >7 days were significantly associated with delirium. The proportion of children screened positive was not significantly different after the implementation (before, 39.7% vs. after, 43.5%; P=0.713). Subgroup analyses revealed a significant reduction in the duration of delirium in children with admission diagnosis of cardiovascular problems and after cardiothoracic surgery.

CONCLUSIONS

The newly implemented protocol was able to reduce the duration of delirium in children with admission diagnosis of cardiovascular problems and after cardiothoracic surgery. More studies should be conducted to reduce delirium to prevent long-term morbidity after PICU discharge.

Serial assessments of cardiac output and mixed venous oxygen saturation in comatose patients after out-of-hospital cardiac arrest

AIM

To assess the association with outcomes of cardiac index (CI) and mixed venous oxygen saturation (SvO2) in comatose patients resuscitated from out-of-hospital cardiac arrest (OHCA).

METHODS

In the cohort study of 789 patients included in the "BOX"-trial, 565 (77%) patients were included in this hemodynamic substudy (age 62 ± 13 years, male sex 81%). Pulmonary artery catheters were inserted shortly after ICU admission. CI and SvO2 were measured as soon as possible in the ICU and until awakening or death. The endpoints were all-cause mortality at 1 year and renal failure defined as need for renal replacement therapy.

RESULTS

First measured CI was median 1.7 (1.4-2.1) l/min/m2, and first measured SvO2 was median 67 (61-73) %. CI < median with SvO2 > median was present in 222 (39%), and low SvO2 with CI < median was present in 59 (11%). Spline analysis indicated that SvO2 value < 55% was associated with poor outcome. Low CI at admission was not significantly associated with mortality in multivariable analysis (p = 0.14). SvO2 was significantly inversely associated with mortality (hazard ratioadjusted: 0.91 (0.84-0.98) per 5% increase in SvO2, p = 0.01). SvO2 was significantly inversely associated with renal failure after adjusting for confounders (ORadjusted: 0.73 [0.62-0.86] per 5% increase in SvO2, p = 0.001). The combination of lower CI and lower SvO2 was associated with higher risk of mortality (hazard ratioadjusted: 1.54 (1.06-2.23) and renal failure (ORadjusted: 5.87 [2.34-14.73].

CONCLUSION

First measured SvO2 after resuscitation from OHCA was inversely associated with mortality and renal failure. If SvO2 and CI were below median, the risk of poor outcomes increased significantly.

REGISTRATION

The BOX-trial is registered at clinicaltrials.gov (NCT03141099, date 2017-30-04, retrospectively registered).

Endotoxin removal therapy with Polymyxin B immobilized fiber column: a single center experience from EUPHAS2 registry

Although the precise clinical indication for initiation of PMX-HA is widely debated in the literature, a proper patient selection and timing of treatment delivery might play a critical role in the clinical course of a specific subphenotype of septic shock (endotoxic shock). In light of this view, since 2019, we have introduced in our clinical practice a diagnostic-therapeutic flowchart to select patients that can benefit the most from the treatment proposed. In addition, we reported in this study our experience of PMX-HA in a cohort of critically ill patients admitted to our intensive care unit (ICU). We analyzed a single centre, retrospective, observational web-based database (extracted from the EUPHAS2 registry) of critically ill patients admitted to the ICU between January 2016 and May 2021 who were affected by endotoxic shock. Patients were divided according to the diagnostic-therapeutic flowchart in two groups: Pre-Flowchart (Pre-F) and Post-Flowchart (Post-F). From January 2016 to May 2021, 61 patients were treated with PMX-HA out of 531 patients diagnosed with septic shock and of these, fifty patients (82%) developed AKI during their ICU stay. The most common source of infection was secondary peritonitis (36%), followed by community-acquired pneumonia (29%). Fifty-five (90%) out of 61 patients received a second PMX-HA treatment, with a statistically significant difference between the two groups (78% of the Pre-F vs. 100% of the Post-F group, p = 0.005). In both groups, between T0 and T120, the Endotoxin Activity Assay (EAA) decreased, while the SOFA score, mean arterial pressure (MAP), and Vasoactive Inotropic Score (VIS) improved with no statistically significant difference. Furthermore, when performing a propensity score matching analysis to compare mortality between the two groups, statistically significant lower ICU and 90-day mortalities were observed in the Post-F group [p = 0.016]. Although in this experienced centre data registry, PMX-HA was associated with organ function recovery, hemodynamic improvement, and current EAA level reduction in critically ill patients with endotoxic shock. Following propensity score-matched analysis, ICU mortality and 90-day mortalities were lower in the diagnostic-therapeutic flowchart group when considering two temporal groups based on strict patient selection criteria and timing to achieve PMX. Further Randomised Control Trials focused on centre selection, adequate training and a flowchart of action when assessing extracorporeal blood purification use should be performed.

Temporary Mechanical Circulatory Support in Cardiogenic Shock Patients after Cardiac Procedures: Selection Algorithm and Weaning Strategies

Mechanical circulatory support has proven effective in managing postcardiotomy cardiogenic shock by stabilizing patients' hemodynamics and ensuring adequate organ perfusion. Among the available device modalities, the combination of extracorporeal life support and a microaxial flow pump for left ventricular unloading has emerged as a valuable tool in the surgical armamentarium. In this publication, we provide recommendations for the application and weaning of temporary mechanical circulatory support in cardiogenic shock patients, derived from a consensus among leading cardiac centers in German-speaking countries.

No association between pulmonary artery catheter use and postoperative complications in off-pump coronary artery bypass grafting: a single-center pilot study

BACKGROUND

A pulmonary artery catheter is often used in cardiac surgery despite its uncertain effectiveness. The aim of this pilot study was to investigate the associations between the use of a pulmonary artery catheter and clinical outcomes in off-pump coronary artery bypass grafting.

METHODS

Patients over 20 years of age who had undergone off-pump coronary artery bypass grafting between December 2018 and November 2021 were enrolled in this single-center retrospective pilot study. The propensity score of pulmonary artery catheterization was calculated. Multivariate analysis including the propensity score as a covariate was performed to assess clinical outcomes. The primary outcome was the composite outcome of in-hospital death, unplanned intraoperative conversion to cardiopulmonary bypass, resuscitated cardiac arrest, mechanical circulatory support, myocardial infarction, stroke, new initiation of renal replacement therapy, inhaled nitric oxide, re-intubation and tracheostomy.

RESULTS

Among the 315 patients who were enrolled, 298 were included in the final analysis. A pulmonary artery catheter was inserted in 131 patients. There were 50 patients with the composite outcome including two in-hospital deaths. Multivariate logistic regression analysis showed that pulmonary artery catheterization was not significantly related to the composite outcome. Clinical outcomes worsened significantly as the number of anastomoses increased (odds ratio: 1.450, 95% confidence interval: 1.040-2.040, P=0.029).

CONCLUSIONS

Pulmonary artery catheterization did not improve the clinical outcomes in off-pump coronary artery bypass grafting in this pilot study.

Vasoactive Inotropic Score compared to the sequential organ failure assessment cardiovascular score in intensive care

BACKGROUND

The cardiovascular component of the sequential organ failure assessment (cvSOFA) score may be outdated because of changes in intensive care. Vasoactive Inotropic Score (VIS) represents the weighted sum of vasoactive and inotropic drugs. We investigated the association of VIS with mortality in the general intensive care unit (ICU) population and studied whether replacing cvSOFA with a VIS-based score improves the accuracy of the SOFA score as a predictor of mortality.

METHODS

We studied the association of VIS during the first 24 h after ICU admission with 30-day mortality in a retrospective study on adult medical and non-cardiac emergency surgical patients admitted to Kuopio University Hospital ICU, Finland, in 2013-2019. We determined the area under the receiver operating characteristic curve (AUROC) for the original SOFA and for SOFAVISmax , where cvSOFA was replaced with maximum VIS (VISmax ) categories.

RESULTS

Of 8079 patients, 1107 (13%) died within 30 days. Mortality increased with increasing VISmax . AUROC was 0.813 (95% confidence interval [CI], 0.800-0.825) for original SOFA and 0.822 (95% CI: 0.810-0.834) for SOFAVISmax , p < .001.

CONCLUSION

Mortality increased consistently with increasing VISmax . Replacing cvSOFA with VISmax improved the predictive accuracy of the SOFA score.

Beneficial effects of levosimendan to wean patients from VA-ECMO: a systematic review and meta-analysis

INTRODUCTION

Patients with refractory cardiogenic shock can benefit from veno-arterial extracorporeal membrane oxygenation (VA-ECMO). The use of levosimendan in VA-ECMO patients may facilitate weaning and enhance survival.

EVIDENCE ACQUISITION

MEDLINE, Scopus, Web of Science, and Cochrane were searched from inception to October 10th, 2021. Eligible clinical trials and observational studies reporting the use of levosimendan in VA-ECMO were searched. Two reviewers extracted data and independently assessed the risk of bias. To integrate the data, a random-effect model was applied. The success of weaning from VA-ECMO was the primary outcome.

EVIDENCE SYNTHESIS

Ten observational studies, including a total of 987 patients, were identified. Levosimendan was associated with successful weaning (362/448) compared with controls (328/539) (OR 2.37, 95% CI 1.71-3.28; P=0.01) and reduced mortality (144/433 vs. 258/507) (nine studies, OR 0.53, 95% CI 0.36-0.78; P=0.01) compared with control.

CONCLUSIONS

Levosimendan was associated with successful weaning and increased survival in VA-ECMO patients. Randomized trials should confirm these findings.

Extracorporeal Blood Purification with CytoSorb in 359 Critically Ill Patients

INTRODUCTION

Critically ill patients with inflammatory dysregulation and organ disfunction may benefit from blood purification, although the use of this technique has not been described in large case series. We evaluated clinical outcomes and survival in high-risk intensive care unit (ICU) patients who underwent extracorporeal blood purification.

METHODS

359 consecutive ICU patients treated with CytoSorb were included.

RESULTS

Main admission diagnoses were 120 (34%) refractory cardiac arrest under mechanical chest compression; 101 (28%) profound cardiogenic shock; 81 (23%) post-cardiotomy cardiogenic shock; and 37 (10%) respiratory failure. Fifteen patients (4%) were positive for SARS-CoV-2 infection. We observed 49% 30-day mortality, 57% ICU mortality, and 62% hospital mortality, all lower than the 71% mortality predicted by SAPS II and 68% predicted by SOFA score. Parameters of shock and organ failure, above all vasoactive inotropic score, reduced during CytoSorb treatment. Multivariable analysis identified SAPS II, lactate dehydrogenase, ICU stay duration, vasoactive inotropic score, lactates, intra-aortic counterpulsation on top of VA-ECMO, and total bilirubin as predictors of mortality. No CytoSorb-related complications occurred.

CONCLUSION

CytoSorb treatment was effective in reducing laboratory parameters of shock and vasoactive inotropic score with possible survival implications in a large population of critically ill patients.

Association of anticoagulation use during continuous kidney replacement therapy and 90-day outcomes: A multicentre study

Introduction

Anticoagulation is recommended during continuous kidney replacement therapy (CKRT) to prolong the filter lifespan for optimal filter performance. We aimed to evaluate the effect of anticoagulation during CKRT on dialysis dependence and mortality within 90 days of intensive care unit (ICU) admission.

Method

Our retrospective observational study evaluated the first CKRT session in critically ill adults with acute kidney injury (AKI) in Singapore from April to September 2017. The primary outcome was a composite of dialysis dependence or death within 90 days of ICU admission; the main exposure variable was anticoagulation use (regional citrate anticoagulation [RCA] or systemic heparin). Multivariable logistic regression was performed to adjust for possible confounders: age, female sex, Acute Physiology and Chronic Health Evaluation (APACHE II) score, liver dysfunction, coagulopathy (international normalised ratio[INR] >1.5) and platelet counts of less than 100,000/uL).

Results

The study cohort included 276 patients from 14 participating adult ICUs, of whom 176 (63.8%) experienced dialysis dependence or death within 90 days of ICU admission (19 dialysis dependence, 157 death). Anticoagulation significantly reduced the odds of the primary outcome (adjusted odds ratio [AOR] 0.47, 95% confidence interval [CI] 0.27-0.83, P=0.009). Logistic regression analysis using anticoagulation as a 3-level indicator variable demonstrated that RCA was associated with mortality reduction (AOR 0.46, 95% CI 0.25-0.83, P=0.011), with heparin having a consistent trend (AOR 0.51, 95% CI 0.23-1.14, P=0.102).

Conclusion

Among critically ill patients with AKI, anticoagulation use during CKRT was associated with reduced dialysis or death at 90 days post-ICU admission, which was statistically significant for regional citrate anticoagulation and trended in the same direction of benefit for systemic heparin anticoagulation. Anticoagulation during CKRT should be considered whenever possible.

Study on the Characteristics of Early Cytokine Storm Response to Cardiac Surgery

Cardiac surgery can provoke an acute cytokine storm that may contribute to the development of postoperative multiple organ dysfunction syndrome. We prospectively observed patients undergoing cardiac surgery and divided them into two groups: the severe group and the mild group. Healthy individuals were enrolled acting as the control group for comparison. Plasma samples and clinical data were recorded at the initiation of cardiac-pulmonary bypass (CPB) and 3, 6, 12, 24, and 48 h after initiation of CPB. Cytokine levels were detected using the Luminex® technique. Thirty-nine adults were enrolled in this study (14 in the severe group, 15 in the mild group, and 10 in the control group). Cytokine concentrations were significantly higher in the severe group. Principal component analysis was used to establish a cytokine storm intensity curve, which represented the overall trend of 10 cytokines. The peak concentrations of interleukin (IL)-6, IL-10, and IL-16 were 425.1, 198.5, and 623.0 pg/mL, which were more than 1,200, 1,800, and 240 times the normal level, respectively. The maximum cytokine storm intensity predated the maximum Vasoactive-Inotropic Score (VIS) and Sequential Organ Failure Assessment (SOFA) score in the severe group. Cytokine storm response to cardiac surgery occurred early and was associated with disease severity. Interventions to cytokine storm should be initiated early as guided by cytokine storm biomarkers such as IL-6, IL-10, and IL-16 in severe patients undergoing cardiac surgery. Clinical Trial Registration: ChiCTR1900021351.

Tissue perfusion pressure enables continuous hemodynamic evaluation and risk prediction in the intensive care unit

Treatment of circulatory shock in critically ill patients requires management of blood pressure using invasive monitoring, but uncertainty remains as to optimal individual blood pressure targets. Critical closing pressure, which refers to the arterial pressure when blood flow stops, can provide a fundamental measure of vascular tone in response to disease and therapy, but it has not previously been possible to measure this parameter routinely in clinical care. Here we describe a method to continuously measure critical closing pressure in the systemic circulation using readily available blood pressure monitors and then show that tissue perfusion pressure (TPP), defined as the difference between mean arterial pressure and critical closing pressure, provides unique information compared to other hemodynamic parameters. Using analyses of 5,988 admissions to a modern cardiac intensive care unit, and externally validated with 864 admissions to another institution, we show that TPP can predict the risk of mortality, length of hospital stay and peak blood lactate levels. These results indicate that TPP may provide an additional target for blood pressure optimization in patients with circulatory shock.