Persistence of Central Venous Oxygen Desaturation During Early Sepsis Is Associated With Higher Mortality

The Inadequate Oxygen Delivery Index and Its Correlation with Venous Saturation in the Pediatric Cardiac Intensive Care Unit

Continuous monitoring software, T3, has an integrated index called the inadequate oxygen delivery index 50% (IDO2-50) which displays a probability that the mixed venous saturation is below a user-selected threshold of 30-50%. The primary aim of this study was to determine the correlation of the IDO2-50 with a measured venous saturation. The secondary aim of this study was to characterize the hemodynamic factors that contributed to the IDO2-50. This single-center, retrospective study aimed to characterize the correlation between IDO2-50 and inferior vena cava (IVC) saturation. A Bayesian Pearson correlation was conducted to assess the correlation between the collected variables of interest, with a particular interest in the correlation between the IDO2-50 and the IVC saturation. Receiver operator curve (ROC) analysis to assess the ability of the IDO2-50 to identify when the venous saturation was less than 50%. Bayesian linear regression was done with the IDO2-50 (dependent variable) and other independent variables. A total of 113 datasets were collected across 15 unique patients. IDO2-50 had moderate correlation with the IVC saturation (correlation coefficient - 0.569). The IDO2-50 had a weak but significant correlation with cerebral near-infrared spectroscopy (NIRS) values, a weak but significant correlation with heart rate, and a moderate and significant correlation with arterial saturation. ROC analysis demonstrated that the IDO2-50 had a good ability to identify a venous saturation below 50%, with an area under the curve of 0.797, cutoff point of 24.5 with a sensitivity of 81%, specificity of 66%, positive predictive value of 44%, and negative predictive value of 91%. Bayesian linear regression analysis yielded the following model: 237.82 + (1.18 × age in months) - (3.31 × arterial saturation) - (1.92 × cerebral NIRS) + (0.84 × heart rate). The IDO2 index has moderate correlation with IVC saturation. It has good sensitive and negative predictive value. Cerebral NIRS does appear to correlate better with the underlying venous saturation than the IDO2 index.

Efficacy of Early Goal-Directed Therapy in Septic Shock Management: A Systematic Review

Septic shock is a serious and life-threatening illness marked by potentially fatal and metabolic abnormalities, leading to high mortality rates in adult patients. Early goal-directed therapy (EGDT) was introduced as a systematic approach to manage septic shock through early, protocol-based hemodynamic optimization to improve outcomes. This systematic review aims to evaluate the efficacy of EGDT in managing adult patients with septic shock. A comprehensive search was conducted in multiple databases to identify relevant studies. Randomized controlled trials (RCTs), quasi-experimental, and observational studies with control groups were included. The quality of the studies was assessed using appropriate tools, and data was extracted for synthesis. This systemic review of 31 observational and RCT studies highlights the shortcomings of the one-size-fits-all EGDT strategy for septic shock. Although the preliminary research was encouraging, more recent studies have shown how important customized approaches are. Sophisticated monitoring methods such as tissue oxygenation and OER show potential in supporting customized hemodynamic therapy. Rigid protocols might not be the best option, but early intervention is essential. A move toward individualized treatment is necessary to enhance the prognosis of individuals suffering from septic shock. Future research should focus on well-designed RCTs, exploring comparative effectiveness, sustainability, and alternative monitoring techniques to refine the role of EGDT and develop more effective, evidence-based management strategies.

Hemodynamic goals in sepsis and septic shock resuscitation: An umbrella review of systematic reviews and meta-analyses with trial sequential analysis

OBJECTIVE

The objective of this study was to verify whether any parameter among those used as the target for haemodynamic optimisation (e.g., mean arterial pressure, central venous oxygen saturation, systolic or diastolic dysfunction, CO2 gap, lactates, right ventricular dysfunction, and PvaCO2/CavO2 ratio) is correlated with mortality in an undifferentiated population with sepsis or septic shock.

METHODS

An umbrella review, searching MEDLINE, the Cochrane Database of Systematic Reviews, Health Technology Assessment Database, and the JBI Database of Systematic Reviews and Implementation Reports, was performed. We included systematic reviews and meta-analyses enrolling a population of unselected patients with sepsis or septic shock. The main outcome was mortality. Two authors conducted data extraction and risk-of-bias assessments independently. We used a random-effects model to pool binary and continuous data and summarised estimates of effect using equivalent odds ratios (eORs). We used the ROBIS tool to assess risk of bias and the assessment of multiple systematic reviews 2 score to assess global quality.

DATA SYNTHESIS

17 systematic reviews and meta-analyses (15 828 patients) were included in the quantitative analysis. Diastolic dysfunction (eOR: 1.42; 95% confidence interval [CI]: 1.14-1.76), PvaCO2/CavO2 ratio (eOR: 2.15; 95% CI: 1.37-3.37), and CO2 gap (eOR: 1.86; 95% CI: 1.07-3.25) showed a significant correlation with mortality. Lactates were the parameter with highest inconsistency (I2 = 92%). Central venous oxygen saturation and right ventricle dysfunction showed significant statistical excess test of significance (p-value = 0.009 and 0.005, respectively). None of the considered parameters showed statistically significant publication bias.

CONCLUSIONS

According to this umbrella review, diastolic dysfunction is the haemodynamic variable that is most closely linked to the prognosis of septic patients. The PvaCO2/CavO2 ratio and the CO2gap are significantly related to the mortality of septic patients, but the poor quality of evidence or the low number of cases, studied so far, limit their clinical applicability.

CLINICAL TRIAL REGISTRATION

PROSPERO: International prospective register of systematic reviews, 2023, CRD42023432813 (Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023432813).

The relationship between perioperative central venous oxygen saturation and postoperative complications in highly invasive gastroenterological surgery

Purpose

Operations for malignant diseases of the bile duct, pancreas, and esophagus are the most invasive gastroenterological surgeries. The frequency of complications after these surgeries is high, which affects the postoperative course and mortality. In patients who undergo these types of surgeries, continuous monitoring of the perioperative central venous oxygen saturation (ScvO2) is possible via a central venous catheter. We aimed to investigate the relationship between continuously monitored perioperative ScvO2 values and postoperative complications.

Methods

The medical records of 115 patients who underwent highly invasive gastroenterological surgeries and ScvO2 monitoring from April 2012 to March 2014 were analyzed. Sixty patients met the inclusion criteria, and their ScvO2 levels were continuously monitored perioperatively. The relationship between ScvO2 levels and major postoperative complications, defined as Clavien-Dindo grade ≥ III, was examined using uni- and multivariate analysis.

Results

Thirty patients developed major postoperative complications. The adequate cut-off value derived from receiver operating curves of the postoperative average ScvO2 levels for predicting major complications was 75%. Multivariate analysis revealed that low average postoperative ScvO2 levels (p = 0.016) and blood loss ≥ 1000 mL (p = 0.039) were significant predictors of major postoperative complications.

Conclusions

Low perioperative ScvO2 values were associated with an increased risk of major postoperative complications. Continuous ScvO2 monitoring will help prevent postoperative complications.

Early high-volume resuscitation with crystalloid solution combined with albumin improves survival of critically ill patients: A retrospective analysis from MIMIC-IV database

BACKGROUND

Volume resuscitation is often required in critically ill patients. However, we have no clear consensus on the choice between crystalloid solution and colloidal solution. This study aimed to explore the effect of albumin administration in massive fluid resuscitation.

METHODS

This was a retrospective cohort study based on the Medical Information Mart for Intensive Care IV (MIMIC-IV) database (2008 and 2019). The prognosis of patients receiving albumin in combination with crystalloids and those receiving crystalloids alone was compared to assess the benefits of albumin in fluid resuscitation.

RESULTS

4426 patients received crystalloids alone (crystalloids group), 692 patients received albumin in combination with crystalloids within the first 24 h of initiation of crystalloids (early albumin combination group), and 382 patients received albumin after the first 24 h (late albumin combination group). Patients in early albumin combination group were more severe than those in Crystalloids group. Nevertheless, we found no statistically significant difference in mortality between the two groups. Multivariate logistic regression analysis using the propensity-score matched cohort showed that the 28-day and 60-day mortality in the early albumin combination group were lower than those in the crystalloids group (odds ratio: 0.64 [95% CI 0.50-0.82; P < 0.001] and 0.71 [95% CI 0.56-0.90; P = 0.004], respectively. Patients in early albumin combination group lived, on average, 1.16 days (95% CI 0.33-2.00; P < 0.01) and 3.3 days (95% CI 1.15-5.44; P < 0.01) longer than the crystalloids group during 28-day follow-up and 60-day follow-up.

CONCLUSION

Administration of albumin within 24 h after the initiation of crystalloids was associated with a lower mortality and a longer restricted mean survival time during 28-day follow-up and 60-day follow-up compared with crystalloid infusion alone. However, administration of albumin 24 h after the initiation of crystalloids was not associated with better prognosis compared to crystalloid infusion alone.

Evaluating the effects of Esmolol on cardiac function in patients with Septic cardiomyopathy by Speck-tracking echocardiography-a randomized controlled trial

BACKGROUND

Esmolol as one treatment of sepsis induced cardiomyopathy (SIC) is still controversial. The objective of this study is to evaluate cardiac function after reducing heart rate by Esmolol in patients with SIC using speck-tracking echocardiography.

METHODS

This study was a single-center, prospective, and randomized controlled study. A total of 100 SIC patients with a heart rate more than 100/min, admitted to the Intensive Care Department of Tianjin Third Central Hospital from March 1, 2020 to September 30, 2021, were selected as the research subjects. They were randomly divided into the Esmolol group (Group E) and the conventional treatment group (Group C), each with 50 cases. The target heart rate of patients in Group E was controlled between 80/min and 100/min. Speck-tracking echocardiography (STE) and pulse indicating continuous cardiac output monitoring (PICCO) were performed in both groups at 1 h, 24 h, 48 h, 72 h, 96 h and 7 d after admission, with data concerning left ventricular global longitudinal strain (GLS), left ventricular ejection fraction (LVEF) and global ejection fraction (GEF), left ventricular systolic force index (dP/dtmx) were obtained, respectively. Hemodynamics and other safety indicators were monitored throughout the whole process. These subjects were followed up to 90 d, with their mortality recorded at Day 28 and Day 90, respectively. Statistical analyses were performed using SPSS version 21.

RESULTS

With 24 h of Esmolol, all patients in Group E achieved the target heart rate, and there was no deterioration of GLS, or adverse events. However, compared with those in Group C, their GLS, GEF and dP/dtmx were increased, and the difference was statistically significant (P > 0.05). Compared with patients in Group C, those in Group E had lower short-term mortality, and logistic regression analysis also suggested that Esmolol improved patient outcomes.

CONCLUSION

In SIC patients, the application of Esmolol to lower heart rate decreased their short-term mortality while not making any impairment on the myocardial contractility.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2100047513. Registered June 20, 2021- Retrospectively registered, http://www.chictr.org.cn/index.aspx . The study protocol followed the CONSORT guidelines. The study protocol was performed in the relevant guidelines.

Venous blood gases in pediatric patients: a lost art?

Blood oximetry provides a fundamental approach to blood gases for inpatients. Arterial blood gases (ABG) have been considered the gold standard for blood oximetry assessment. Venous blood gas (VBG) evaluation is frequently available and provides a source of a more comfortable method for the assessment of blood oximetry in pediatric patients. Some data provided by the venous blood gas can be additive and offer insights apart from the arterial blood gas. The purpose of this review was to provide an assessment of the performance of VBG in pediatric patients. The study concludes that VBG are helpful tools in assessing oxygenation and ventilation in critically ill children and can be used as a marker of adequacy of systemic oxygen delivery. In the setting of systemic oxygen delivery decrease or oxygen extraction increase, the partial pressure of oxygen on the VBG will decrease. Thus, the partial pressure of oxygen and the corresponding venous saturation can be a marker of systemic oxygen delivery in a variety of illnesses. Simultaneous ABG and VBG comparison can actually lend great insight to not only the respiratory status of a patient but provide an assessment of the adequacy of cardiac output and systemic oxygen delivery.

Increased ratio of P[v-a]CO2 to C[a-v]O2 without global hypoxia: the case of metformin-induced lactic acidosis

The ratio of venoarterial CO2 tension to arteriovenous O2 content difference (P[v-a]CO2/C[a-v]O2) increases when lactic acidosis is due to inadequate oxygen supply (hypoxia); we aimed to verify whether it also increases when lactic acidosis develops because of mitochondrial dysfunction (dysoxia) with constant oxygen delivery. Twelve anaesthetised, mechanically ventilated pigs were intoxicated with IV metformin (4.0 to 6.4 g over 2.5 to 4.0 h). Saline and norepinephrine were used to preserve oxygen delivery. Lactate and P[v-a]CO2/C[a-v]O2 were measured every one or two hours (arterial and mixed venous blood). During metformin intoxication, lactate increased from 0.8 (0.6-0.9) to 8.5 (5.0-10.9) mmol/l (p < 0.001), even if oxygen delivery remained constant (from 352 ± 78 to 343 ± 97 ml/min, p = 0.098). P[v-a]CO2/C[a-v]O2 increased from 1.6 (1.2-1.8) to 2.3 (1.9-3.2) mmHg/ml/dl (p = 0.004). The intraclass correlation coefficient between lactate and P[v-a]CO2/C[a-v]O2 was 0.72 (p < 0.001). We conclude that P[v-a]CO2/C[a-v]O2 increases when lactic acidosis is due to dysoxia. Therefore, a high P[v-a]CO2/C[a-v]O2 may not discriminate hypoxia from dysoxia as the cause of lactic acidosis.

Individualized Hemodynamic Management in Sepsis

Hemodynamic optimization remains the cornerstone of resuscitation in the treatment of sepsis and septic shock. Delay or inadequate management will inevitably lead to hypoperfusion, tissue hypoxia or edema, and fluid overload, leading eventually to multiple organ failure, seriously affecting outcomes. According to a large international survey (FENICE study), physicians frequently use inadequate indices to guide fluid management in intensive care units. Goal-directed and "restrictive" infusion strategies have been recommended by guidelines over "liberal" approaches for several years. Unfortunately, these "fixed regimen" treatment protocols neglect the patient's individual needs, and what is shown to be beneficial for a given population may not be so for the individual patient. However, applying multimodal, contextualized, and personalized management could potentially overcome this problem. The aim of this review was to give an insight into the pathophysiological rationale and clinical application of this relatively new approach in the hemodynamic management of septic patients.

This is your toolkit in hemodynamic monitoring

PURPOSE OF REVIEW

To appraise the basic and more advanced methods available for hemodynamic monitoring, and describe the definitions and criteria for the use of hemodynamic variables.

RECENT FINDINGS

The hemodynamic assessment in critically ill patients suspected of circulatory shock follows a step-by-step algorithm to help determine diagnosis and prognosis. Determination of accurate diagnosis and prognosis in turn is crucial for clinical decision-making. Basic monitoring involving clinical examination in combination with hemodynamic variables obtained with an arterial catheter and a central venous catheter may be sufficient for the majority of patients with circulatory shock. In case of uncertainty of the underlying cause or to guide treatment in severe shock may require additional advanced hemodynamic technologies, and each is utilized for different indications and has specific limitations. Future developments include refining the clinical examination and performing studies that demonstrate better patient outcomes by targeting hemodynamic variables using advanced hemodynamic monitoring.

SUMMARY

Determination of accurate diagnosis and prognosis for patients suspected of circulatory shock is essential for optimal decision-making. Numerous techniques are available, and each has its specific indications and value.

A Physiologic Approach to Hemodynamic Monitoring and Optimizing Oxygen Delivery in Shock Resuscitation

The approach to shock resuscitation focuses on all components of oxygen delivery, including preload, afterload, contractility, hemoglobin, and oxygen saturation. Resuscitation focused solely on preload and fluid responsiveness minimizes other key elements, resulting in suboptimal patient care. This review will provide a physiologic and practical approach for the optimization of oxygen delivery utilizing available hemodynamic monitoring technologies. Venous oxygen saturation (SvO₂) and lactate will be discussed as indicators of shock states and endpoints of resuscitation within the framework of resolving oxygen deficit and oxygen debt.

Sepsis With Preexisting Heart Failure: Management of Confounding Clinical Features

Preexisting heart failure (HF) in patients with sepsis is associated with worse clinical outcomes. Core sepsis management includes aggressive volume resuscitation followed by vasopressors (and potentially inotropes) if fluid is inadequate to restore perfusion; however, large fluid boluses and vasoactive agents are concerning amid the cardiac dysfunction of HF. This review summarizes evidence regarding the influence of HF on sepsis clinical outcomes, pathophysiologic concerns, resuscitation targets, hemodynamic interventions, and adjunct management (ie, antiarrhythmics, positive pressure ventilatory support, and renal replacement therapy) in patients with sepsis and preexisting HF. Patients with sepsis and preexisting HF receive less fluid during resuscitation; however, evidence suggests traditional fluid resuscitation targets do not increase the risk of adverse events in HF patients with sepsis and likely improve outcomes. Norepinephrine remains the most well-supported vasopressor for patients with sepsis with preexisting HF, while dopamine may induce more cardiac adverse events. Dobutamine should be used cautiously given its generally detrimental effects but may have an application when combined with norepinephrine in patients with low cardiac output. Management of chronic HF medications warrants careful consideration for continuation or discontinuation upon development of sepsis, and β-blockers may be appropriate to continue in the absence of acute hemodynamic decompensation. Optimal management of atrial fibrillation may include β-blockers after acute hemodynamic stabilization as they have also shown independent benefits in sepsis. Positive pressure ventilatory support and renal replacement must be carefully monitored for effects on cardiac function when HF is present.

Hemodynamic monitoring in patients with venoarterial extracorporeal membrane oxygenation

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an effective mechanical circulatory support modality that rapidly restores systemic perfusion for circulatory failure in patients. Given the huge increase in VA-ECMO use, its optimal management depends on continuous and discrete hemodynamic monitoring. This article provides an overview of VA-ECMO pathophysiology, and the current state of the art in hemodynamic monitoring in patients with VA-ECMO.

Minimizing catecholamines and optimizing perfusion

Catecholamines are used to increase cardiac output and blood pressure, aiming ultimately at restoring/improving tissue perfusion. While intuitive in its concept, this approach nevertheless implies to be effective that regional organ perfusion would increase in parallel to cardiac output or perfusion pressure and that the catecholamine does not have negative effects on the microcirculation. Inotropic agents may be considered in some conditions, but it requires prior optimization of cardiac preload. Alternative approaches would be either to minimize exposure to vasopressors, tolerating hypotension and trying to prioritize perfusion but this may be valid as long as perfusion of the organ is preserved, or to combine moderate doses of vasopressors to vasodilatory agents, especially if these are predominantly acting on the microcirculation. In this review, we will discuss the pros and cons of the use of catecholamines and alternative agents for improving tissue perfusion in septic shock.