Enteral nutrition in septic shock: a call for a paradigm shift.

PURPOSE OF REVIEW: The purpose of this review is to identify contemporary evidence evaluating enteral nutrition in patients with septic shock, outline risk factors for enteral feeding intolerance (EFI), describe the conundrum of initiating enteral nutrition in patients with septic shock, appraise current EFI definitions, and identify bedside monitors for guiding enteral nutrition therapy. RECENT FINDINGS: The NUTRIREA-2 and NUTRIREA-3 trial results have better informed the dose of enteral nutrition in critically ill patients with circulatory shock. In both trials, patients with predominant septic shock randomized to receive early standard-dose nutrition had more gastrointestinal complications. Compared to other contemporary RCTs that included patients with circulatory shock, patients in the NUTRIREA-2 and NUTRIREA-3 trials had higher bowel ischemia rates, were sicker, and received full-dose enteral nutrition while receiving high baseline dose of vasopressor. These findings suggest severity of illness, vasopressor dose, and enteral nutrition dose impact outcomes. SUMMARY: The provision of early enteral nutrition preserves gut barrier functions; however, these benefits are counterbalanced by potential complications of introducing luminal nutrients into a hypo-perfused gut, including bowel ischemia. Findings from the NUTRIREA2 and NUTRIREA-3 trials substantiate a 'less is more' enteral nutrition dose strategy during the early acute phase of critical illness. In the absence of bedside tools to guide the initiation and advancement of enteral nutrition in patients with septic shock, the benefit of introducing enteral nutrition on preserving gut barrier function must be weighed against the risk of harm by considering dose of vasopressor, dose of enteral nutrition, and severity of illness.

Hemoadsorption Therapy for Calcium Channel Blocker Overdose: A Case Report.

BACKGROUND: Modern resin hemoadsorption/hemoperfusion for calcium channel blocker overdose is yet to be reported. The characteristics of calcium channel blockers make them unamenable to removal by hemodiafiltration or charcoal hemoperfusion; however, elimination, using styrene bead adsorption in an ex vivo model, has been demonstrated. Its clinical use is described. CASE REPORT: A man in his 20s was admitted with shock into the Intensive Care Unit (ICU) after an overdose of amlodipine and risperidone. Resuscitation and supportive care were administered, but hypotension did not resolve despite the administration of intravenous fluids, infusions of calcium, adrenaline, and hyperinsulinemic-euglycemic therapy. Methylene blue was then administered to maintain the mean arterial pressures. However, the hemodynamic effect did not allow the weaning of the adrenaline. Drug clearance using hemoadsorption/hemoperfusion was attempted using a styrene resin filter (Jafron HA230; Jafron Biomedical Co., Ltd., Guangdong, China). During the two hemoperfusion sessions (6 h duration each, and 18 h apart) the patient had successfully weaned off all supportive measures, with lactate levels returning to normal and was later discharged home. At the end of each session, significant amlodipine concentrations were detected in blood aspirated from both filters, suggesting enhanced clearance. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Our case illustrates a temporal relationship between resin hemoperfusion therapy, resolution of hemodynamic instability, and shock without proving causation. Significant amlodipine elimination was suggested by high concentrations found in blood from the filter. At the same time, shock resolution after initiation of hemoperfusion occurred in less than one elimination half-life of amlodipine.

Dynamic monitoring tools for patients admitted to the emergency department with circulatory failure: narrative review with panel-based recommendations.

Intravenous fluid therapy is commonly administered in the emergency department (ED). Despite the deleterious potential of over- and under-resuscitation, professional society guidelines continue to recommend administering a fixed volume of fluid in initial resuscitation. Predicting whether a specific patient will respond to fluid therapy remains one of the most important, but challenging questions that ED clinicians face in clinical practice. Surrogate parameters (i.e. blood pressure and heart rate), are widely used in usual care to estimate changes in stroke volume (SV). Due to their inadequacy in estimating SV, noninvasive techniques (e.g. bioreactance, echocardiography, noninvasive finger cuff technology), have been proposed as a more accurate and readily deployable method for assessing flow and preload responsiveness. Dynamic monitoring systems based on cardiac preload challenge and assessment of SV, by using noninvasive and continuous methods, provide more accurate, feasible, efficient, and reasonably accurate strategy for prediction of fluid responsiveness than static measurements. In this article, we aimed to analyze the different methods currently available for dynamic monitoring of preload responsiveness.

Improving the precision of shock resuscitation by predicting fluid responsiveness with machine learning and arterial blood pressure waveform data.

Fluid bolus therapy (FBT) is fundamental to the management of circulatory shock in critical care but balancing the benefits and toxicities of FBT has proven challenging in individual patients. Improved predictors of the hemodynamic response to a fluid bolus, commonly referred to as a fluid challenge, are needed to limit non-beneficial fluid administration and to enable automated clinical decision support and patient-specific precision critical care management. In this study we retrospectively analyzed data from 394 fluid boluses from 58 pigs subjected to either hemorrhagic or distributive shock. All animals had continuous blood pressure and cardiac output monitored throughout the study. Using this data, we developed a machine learning (ML) model to predict the hemodynamic response to a fluid challenge using only arterial blood pressure waveform data as the input. A Random Forest binary classifier referred to as the ML fluid responsiveness algorithm (MLFRA) was trained to detect fluid responsiveness (FR), defined as a ≥ 15% change in cardiac stroke volume after a fluid challenge. We then compared its performance to pulse pressure variation, a commonly used metric of FR. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC), confusion matrix metrics, and calibration curves plotting predicted probabilities against observed outcomes. Across multiple train/test splits and feature selection methods designed to assess performance in the setting of small sample size conditions typical of large animal experiments, the MLFRA achieved an average AUROC, recall (sensitivity), specificity, and precision of 0.82, 0.86, 0.62. and 0.76, respectively. In the same datasets, pulse pressure variation had an AUROC, recall, specificity, and precision of 0.73, 0.91, 0.49, and 0.71, respectively. The MLFRA was generally well-calibrated across its range of predicted probabilities and appeared to perform equally well across physiologic conditions. These results suggest that ML, using only inputs from arterial blood pressure monitoring, may substantially improve the accuracy of predicting FR compared to the use of pulse pressure variation. If generalizable, these methods may enable more effective, automated precision management of critically ill patients with circulatory shock.

Performance of Tools and Measures to Predict Fluid Responsiveness in Pediatric Shock and Critical Illness: A Systematic Review and Meta-Analysis.

OBJECTIVES: In this systematic review and meta-analysis we asked: Do predictors of fluid responsiveness in children perform comparably: 1) in the PICU as in non-PICU settings? 2) in shock states compared with nonshock states? Additionally, 3) is there an association between preload responsiveness and clinical response? DATA SOURCES: Ovid Medline, PubMed, and Embase databases were searched from inception through May 2022. STUDY SELECTION: Included studies reported physiological response to IV fluid administration in humans less than 18 years. Only studies reporting an area under the receiver operating characteristic curve (AUROC) were included for descriptive analysis. Only studies for which a se could be estimated were included for meta-analysis. DATA EXTRACTION: Title, abstract, full text screening, and extraction were completed by two authors (S.B.W., J.M.W.). Variables extracted included predictors ("tools") and outcome measures ("reference tests") of fluid responsiveness, demographic, and clinical variables. DATA SYNTHESIS: We identified 62 articles containing 204 AUROCs for 55 tools, primarily describing mechanically ventilated children in an operating room or PICU. Meta-analysis across all tools showed poor predictive performance (AUROC, 0.66; 95% CI, 0.63-0.69), although individual performance varied greatly (range, 0.49-0.87). After controlling for PICU setting and shock state, PICU setting was associated with decreased predictive performance (coefficient, -0.56; p = 0.0007), while shock state was associated with increased performance (0.54; p = 0.0006). Effect of PICU setting and shock state on each tool was not statistically significant but analysis was limited by sample size. The association between preload responsiveness and clinical response was rarely studied but results did not suggest an association. Ultrasound measurements were prone to inherent test review and incorporation biases. CONCLUSIONS: We suggest three opportunities for further research in fluid responsiveness in children: 1) assessing predictive performance of tools during resuscitation in shock states; 2) separating predictive tool from reference test when using ultrasound techniques; and 3) targeting decreasing time in a shock state, rather than just increase in preload.

PROGNOSTIC PERFORMANCE OF SERIAL DETERMINATION OF THE SOCIETY FOR CARDIOVASCULAR ANGIOGRAPHY AND INTERVENTIONS SHOCK CLASSIFICATION IN ADULTS WITH CRITICAL ILLNESS.

ABSTRACT: Purpose: The aim of the study is to evaluate whether serial assessment of shock severity can improve prognostication in intensive care unit (ICU) patients. Materials and Methods: This is a retrospective cohort of 21,461 ICU patient admissions from 2014 to 2018. We assigned the Society for Cardiovascular Angiography and Interventions (SCAI) Shock Stage in each 4-h block during the first 24 h of ICU admission; shock was defined as SCAI Shock stage C, D, or E. In-hospital mortality was evaluated using logistic regression. Results: The admission SCAI Shock stages were as follows: A, 39.0%; B, 27.0%; C, 28.9%; D, 2.6%; and E, 2.5%. The SCAI Shock stage subsequently increased in 30.6%, and late-onset shock developed in 30.4%. In-hospital mortality was higher in patients who had shock on admission (11.9%) or late-onset shock (7.3%) versus no shock (4.3%). Persistence of shock predicted higher mortality (adjusted OR = 1.09; 95% CI = 1.06-1.13, for each ICU block with shock). The mean SCAI Shock stage had higher discrimination for in-hospital mortality than the admission or maximum SCAI Shock stage. Dynamic modeling of the SCAI Shock classification improved discrimination for in-hospital mortality (C-statistic = 0.64-0.71). Conclusions: Serial application of the SCAI Shock classification provides improved mortality risk stratification compared with a single assessment on admission, facilitating dynamic prognostication.

How to use echocardiography to manage patients with shock?

Echocardiography enables the intensivist to assess the patient with circulatory failure. It allows the clinician to identify rapidly the type and the cause of shock in order to develop an effective management strategy. Important characteristics in the setting of shock are that it is non-invasive and can be rapidly applied. Early and repeated echocardiography is a valuable tool for the management of shock in the intensive care unit. Competency in basic critical care echocardiography is now regarded as a mandatory part of critical care training with clear guidelines available. The majority of pathologies found in shocked patients are readily identified using basic level 2D and M-mode echocardiography. The four core types of shock (cardiogenic, hypovolemic, obstructive, and septic) can readily be identified by echocardiography. Echocardiography can differentiate the different pathologies that may be the cause of each type of shock. More importantly, as a result of more complex and elderly patients, the shock may be multifactorial, such as a combination of cardiogenic and septic shock, which emphasises on the added value of transthoracic echocardiography (TTE) in such population of patients. In this review we aimed to provide to clinicians a bedside strategy of the use of TTE parameters to manage patients with shock. In the first part of this overview, we detailed the different TTE parameters and how to use them to identify the type of shock. And in the second part, we focused on the use of these parameters to evaluate the effect of treatments, in different types of shock.

Utilization of non-pneumatic anti-shock garment for treating obstetric hemorrhage and associated factors among obstetric care providers in Ethiopia: A systematic review and meta-analysis.

BACKGROUND: The non-pneumatic anti-shock garment (NASG) is a life-saving device that can help to avoid delays and prevent further complications in the case of obstetric hemorrhage. Although there are many fragmented primary studies on the NASG utilization in Ethiopia, the pooled utilization rate is unknown. In addition, a disagreement was observed among those studies while reporting the associated factors. Therefore, this study was intended to determine the pooled level of NASG utilization and its associated factors among obstetric care providers in Ethiopia. METHODS: A total of 51 studies were retrieved from PubMed, Google Scholar, the African Journal of Online, direct open-access journals, and Ethiopian universities' institutional repositories. This study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The quality of studies was evaluated using the modified Newcastle-Ottawa quality assessment tool. The data were extracted by two authors independently using Microsoft Excel and analyzed by Stata version 11. A random-effects model was applied to calculate the pooled level of NASG utilization and its associated factors. The PROSPERO registration number for the review is CRD42023414043. RESULT: A total of 8 studies comprising 2,575 study participants were involved in this meta-analysis. The pooled utilization rate of NASG was found to be 39.56%. Having NASG training (pooled odds ratio (OR) = 3.99, 95%CI = 2.35, 6.77), good knowledge about NASG (OR = 2.92, 95%CI = 2.04, 4.17), a positive attitude towards NASG (OR = 3.17, 95%CI = 2.10, 4.79), and having ≥ 2 NASGs in the health facility (OR = 10.59, 95%CI = 6.59, 17.01) were significantly associated with NASG utilization. CONCLUSION: Utilization of NASG for the treatment of obstetric hemorrhage was low in Ethiopia. To increase its utilization, Ministry of Health should improve the accessibility of NASG at each health facility and increase the Health professionals' knowledge and attitude through in-service and pre-service training.

Operational demonstration and process evaluation of non-pneumatic anti-shock garment (NASG) introduction to the public health system of Northern Province, Zambia.

BACKGROUND: A disproportionate burden of maternal deaths occurs in low- and middle-income countries (LMICs), and obstetric hemorrhage (OH) is a leading cause of excess mortality. In Zambia, most of maternal deaths are directly caused by OH. The Non-Pneumatic Anti-Shock Garment (NASG) is a first aid tool that uses compression to the abdomen and lower body to stop and reverse hypovolemic shock secondary to OH. We describe the process and experiences introducing the NASG into the Zambia public health system to encourage the development of national policies, clinical guidelines, and implementation plans that feature the NASG. METHODS: We conducted an observational study of NASG introduction to 143 public health facilities in Northern Province, Zambia, organizing observations into the five dimensions of the RE-AIM evaluation framework: reach, effectiveness, adoption, implementation, and maintenance. The NASG was introduced in August 2019, and the introduction was evaluated for 18 months. Data on healthcare worker training and mentorship, cases where NASG was used, and NASG availability and use during the study period were collected and analyzed. RESULTS: The NASG was successfully introduced and integrated into the Zambia public health system, and appropriately used by healthcare workers when responding to cases of OH. Sixteen months after NASG introduction, NASGs were available and functional at 99% of study sites and 88% reported ever using a NASG. Of the 68 cases of recorded OH where a NASG was applied, 66 were confirmed as clinically appropriate, and among cases where shock index (SI) could be calculated, 59% had SI ≥ 0.9. Feedback from healthcare providers revealed that 97% thought introducing the NASG was a good decision, and 92% felt confident in their ability to apply the NASG after initial training. The RE-AIM average for this study was 0.65, suggesting a public health impact that is not equivocal, and that NASG introduction had a positive population-based effect. CONCLUSIONS: A successful NASG demonstration took place over the course of 18 months in the existing health system of Northern Province, Zambia, suggesting that incorporation of NASG into the standard of care for obstetric emergency in the Zambia public sector is feasible and can be maintained without external support.

Pediatric Shock Review.

Shock occurs when there is energy failure due to inadequate oxygen/glucose delivery to meet metabolic demands. Shock is a leading cause of death and disability in children worldwide. Types of shock include hypovolemic, cardiogenic, distributive, and obstructive. This review provides an overview of the epidemiology, pathophysiology, and clinical signs and symptoms of each of these types of shock, followed by a discussion of advancements in diagnostic tests and tools and management/treatment principles for different categories of shock.

Emergency Department Shock Index Outperforms Prehospital and Delta Shock Indices in Predicting Outcomes of Trauma Patients.

INTRODUCTION: Multiple shock indices (SIs), including prehospital, emergency department (ED), and delta (ED SI - Prehospital SI) have been developed to predict outcomes among trauma patients. This study aims to compare the predictive abilities of these SIs for outcomes of polytrauma patients on a national level. METHODS: This was a retrospective analysis of the American College of Surgeons Trauma Quality Improvement Program (2017-2018). We included adult (≥18 y) trauma patients and excluded patients who were transferred, had missing vital signs, and those with severe head injuries (Head-Abbreviated Injury Scale>3). Outcome measures were 24-h and in-hospital mortality, 24-h packed red blood cells transfusions, and intensive care unit and hospital length of stay. Predictive performances of these SIs were evaluated by the Area Under the Receiver Operating Characteristics for the entire study cohort and across all injury severities. RESULTS: A total of 750,407 patients were identified. Meanstandard deviation age and lowest systolic blood pressure were 53 ± 21 y, and 81 ± 32 mmHg, respectively. Overall, 24-h and in-hospital mortality were 1.2% and 2.5%, respectively. On multivariable analysis, all three SIs were independently associated with higher rates of 24-h and in-hospital mortality, blood product requirements, intensive care unit and hospital length of stay (P < 0.001). ED SI was superior to prehospital and delta SIs (P < 0.001) for all outcomes. On subanalysis of patients with moderate injuries, severe injuries, and positive delta SI, the results remained the same. CONCLUSIONS: ED SI outperformed both prehospital and delta SIs across all injury severities. Trauma triage guidelines should prioritize ED SI in the risk stratification of trauma patients who may benefit from earlier and more intense trauma activations.

Utility of Inferior Vena Cava Distensibility and Respiratory Variation in Peak Aortic Blood Flow Velocity to Predict Fluid Responsiveness in Children with Shock.

OBJECTIVES: To evaluate the sensitivity and specificity of inferior vena cava (IVC) distensibility index (∆IVC) and respiratory variation in peak aortic blood flow velocity (∆Vpeak) to predict fluid responsiveness in ventilated children with shock and to find out the best cut-off values for predicting fluid responsiveness. METHODS: In this prospective observational study, conducted in a pediatric ICU from January 2019 through May 2020, consecutive children aged 2 mo to 17 y with shock requiring fluid bolus were included. ∆IVC and ∆Vpeak were measured before and immediately after 10 ml/kg fluid bolus administration. ∆IVC and ∆Vpeak were compared between responders and non-responders, defined by a change in stroke volume index (SVI) of ≥10%. RESULTS: Thirty-seven ventilated children [26 (70.4%) boys] with median age of 60 (36, 108) mo were included. The median (IQR) ∆IVC was 21.7% (14.3, 30.9) and the median (IQR) ΔVpeak was 11.3% (7.2, 15.2). Twenty-three (62%) children were fluid responsive. The median (IQR) ∆IVC was higher in responders compared to non-responders [26% (16.9, 36.5) vs. 17.2% (8.4, 21.9); p = 0.018] and mean (SD) ΔVpeak was higher in responders [13.9% (6.1) vs. 8.4% (3.9), p = 0.004]. The prediction of fluid responsiveness with ΔIVC [ROC curve area 0.73 (0.56-0.9), p = 0.01] and ΔVpeak [ROC curve area 0.78 (0.63-0.94), p = 0.002] was similar. The best cut-off of ∆IVC to predict fluid responsiveness was 23% (sensitivity, 60.8%; specificity, 85.7%) and ΔVpeak was 11.3% (sensitivity, 74%; specificity, 86%). CONCLUSIONS: In this study, authors found that ∆IVC and ΔVpeak were good predictors of fluid responsiveness in ventilated children with shock.

Angiotensin II for the Treatment of Refractory Shock: A Matched Analysis.

OBJECTIVES: To determine if angiotensin II is associated with improved outcomes as measured by 30- and 90-day mortality as well as other secondary outcomes such as organ dysfunction and adverse events. DESIGN: Retrospective, matched analysis of patients receiving angiotensin II compared with both historical and concurrent controls receiving equivalent doses of nonangiotensin II vasopressors. SETTING: Multiple ICUs in a large, university-based hospital. PATIENTS: Eight hundred thirteen adult patients with shock admitted to an ICU and requiring vasopressor support. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Angiotensin II use had no association with the primary outcome of 30-day mortality (60% vs 56%; p = 0.292). The secondary outcome of 90-day mortality was also similar (65% vs 63%; p = 0.440) as were changes in Sequential Organ Failure Assessment scores over a 5-day monitoring period after enrollment. Angiotensin II was not associated with increased rates of kidney replacement therapy (odds ratio [OR], 1.39; 95% CI, 0.88-2.19; p = 0.158) or receipt of mechanical ventilation (OR, 1.50; 95% CI, 0.41-5.51; p = 0.539) after enrollment, and the rate of thrombotic events was similar between angiotensin II and control patients (OR, 1.02; 95% CI, 0.71-1.48; p = 0.912). CONCLUSIONS: In patients with severe shock, angiotensin II was not associated with improved mortality or organ dysfunction and was not associated with an increased rate of adverse events.

Hypovolemic shock due to Wunderlich syndrome (spontaneous renal haemorrhage): a case report and literature review.

Wunderlich syndrome (WS) or spontaneous renal haemorrhage is a rare and life-threatening condition often leading to haemorrhagic shock. WS is characterized by an acute onset of non-traumatic subcapsular and perirenal haematoma formation due to several causes, including neoplasms, cystic rupture, vasculitis, coagulopathies, and infections. The classical presentation includes acute flank or abdominal pain, a palpable flank mass and hypovolemic shock (Lenk's triad). Nausea, vomiting, fever, and haematuria can also be present. Computed tomography angiography is mandatory to localize the source of haemorrhage. Super-selective embolization can be performed to stop bleeding, while surgery is reserved to haemodynamic unstable patients and neoplastic cases. We describe a case of WS in a 79-year-old male patient, who rapidly developed hypovolemic shock requiring urgent nephrectomy.

Nutrition dose in the early acute phase of critical illness: Finding the sweet spot and heeding the lessons from the NUTRIREA trials.

The landmark NUTRIREA-2 and NUTRIREA-3 trials compared the route and dose of nutrition, respectively, in critically ill patients with circulatory shock. The results of both trials support a "less-is-more" paradigm shift in the early acute phase of critical illness. In this review, the authors outline and appraise the results of the NUTRIREA-2 and NUTRIREA-3 trials, introduce the concept of identifying the "sweet spot" for nutrition dose based on severity of illness/nutrition risk and nutrition dose, and identify the unintended consequences of delivering full-dose nutrition in sicker critically ill patients during the early acute phase of critical illness.

Combined Therapeutic Plasma Exchange and Continuous Renal Replacement Therapy in Children With Dengue-Associated Acute Liver Failure and Shock Syndrome: Single-Center Cohort From Vietnam.

OBJECTIVES: Pediatric acute liver failure (PALF) is a fatal complication in patients with severe dengue. To date, clinical data on the combination of therapeutic plasma exchange (TPE) and continuous renal replacement therapy (CRRT) for managing dengue-associated PALF concomitant with shock syndrome are limited. DESIGN: Retrospective cohort study (January 2013 to June 2022). PATIENTS: Thirty-four children. SETTING: PICU of tertiary Children's Hospital No. 2 in Vietnam. INTERVENTIONS: We assessed a before-versus-after practice change at our center of using combined TPE and CRRT (2018 to 2022) versus CRRT alone (2013 to 2017) in managing children with dengue-associated acute liver failure and shock syndrome. Clinical and laboratory data were reviewed from PICU admission, before and 24 h after CRRT and TPE treatments. The main study outcomes were 28-day in-hospital mortality, hemodynamics, clinical hepatoencephalopathy, and liver function normalization. MEASUREMENTS AND MAIN RESULTS: A total of 34 children with a median age of 10 years (interquartile range: 7-11 yr) underwent standard-volume TPE and/or CRRT treatments. Combined TPE and CRRT ( n = 19), versus CRRT alone ( n = 15), was associated with lower proportion of mortality 7 of 19 (37%) versus 13 of 15 (87%), difference 50% (95% CI, 22-78; p < 0.01). Use of combined TPE and CRRT was associated with substantial advancements in clinical hepatoencephalopathy, liver transaminases, coagulation profiles, and blood lactate and ammonia levels (all p values < 0.001). CONCLUSIONS: In our experience of children with dengue-associated PALF and shock syndrome, combined use of TPE and CRRT, versus CRRT alone, is associated with better outcomes. Such combination intervention was associated with normalization of liver function, neurological status, and biochemistry. In our center we continue to use combined TPE and CRRT rather than CRRT alone.