Metabolic and Endocrine Challenges.

This review aims to provide an overview of metabolic and endocrine challenges in the setting of intensive care medicine. These are a group of heterogeneous clinical conditions with a high degree of overlap, as well as nonspecific signs and symptoms. Several diseases involve multiple organ systems, potentially causing catastrophic dysfunction and death. In the majority of cases, endocrine challenges accompany other organ failures or manifest as a complication of prolonged intensive care unit stay and malnutrition. However, when endocrine disorders present as an isolated syndrome, they are a rare and extreme manifestation. As they are uncommon, these can typically challenge both with diagnosis and management. Acute exacerbations may be elicited by triggers such as infections, trauma, surgery, and hemorrhage. In this complex scenario, early diagnosis and prompt treatment require knowledge of the specific endocrine syndrome. Here, we review diabetic coma, hyponatremia, hypercalcemia, thyroid emergencies, pituitary insufficiency, adrenal crisis, and vitamin D deficiency, highlighting diagnostic tools and tricks, and management pathways through defining common clinical presentations.

Identification of a Circulating miRNA Signature to Stratify Acute Respiratory Distress Syndrome Patients.

There is a need to improve acute respiratory distress syndrome (ARDS) diagnosis and management, particularly with extracorporeal membrane oxygenation (ECMO), and different biomarkers have been tested to implement a precision-focused approach. We included ARDS patients on veno-venous (V-V) ECMO in a prospective observational pilot study. Blood samples were obtained before cannulation, and screened for the expression of 754 circulating microRNA (miRNAs) using high-throughput qPCR and hierarchical cluster analysis. The miRNet database was used to predict target genes of deregulated miRNAs, and the DIANA tool was used to identify significant enrichment pathways. A hierarchical cluster of 229 miRNAs (identified after quality control screening) produced a clear separation of 11 patients into two groups: considering the baseline SAPS II, SOFA, and RESP score cluster A (n = 6) showed higher severity compared to cluster B (n = 5); p values < 0.05. After analysis of differentially expressed miRNAs between the two clusters, 95 deregulated miRNAs were identified, and reduced to 13 by in silico analysis. These miRNAs target genes implicated in tissue remodeling, immune system, and blood coagulation pathways. The blood levels of 13 miRNAs are altered in severe ARDS. Further investigations will have to match miRNA results with inflammatory biomarkers and clinical data.

Limb ischemia in peripheral veno-arterial extracorporeal membrane oxygenation: a narrative review of incidence, prevention, monitoring, and treatment.

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is an increasingly adopted life-saving mechanical circulatory support for a number of potentially reversible or treatable cardiac diseases. It is also started as a bridge-to-transplantation/ventricular assist device in the case of unrecoverable cardiac or cardio-respiratory illness. In recent years, principally for non-post-cardiotomy shock, peripheral cannulation using the femoral vessels has been the approach of choice because it does not need the chest opening, can be quickly established, can be applied percutaneously, and is less likely to cause bleeding and infections than central cannulation. Peripheral ECMO, however, is characterized by a higher rate of vascular complications. The mechanisms of such adverse events are often multifactorial, including suboptimal arterial perfusion and hemodynamic instability due to the underlying disease, peripheral vascular disease, and placement of cannulas that nearly occlude the vessel. The effect of femoral artery damage and/or significant reduced limb perfusion can be devastating because limb ischemia can lead to compartment syndrome, requiring fasciotomy and, occasionally, even limb amputation, thereby negatively impacting hospital stay, long-term functional outcomes, and survival. Data on this topic are highly fragmentary, and there are no clear-cut recommendations. Accordingly, the strategies adopted to cope with this complication vary a great deal, ranging from preventive placement of antegrade distal perfusion cannulas to rescue interventions and vascular surgery after the complication has manifested.This review aims to provide a comprehensive overview of limb ischemia during femoral cannulation for VA-ECMO in adults, focusing on incidence, tools for early diagnosis, risk factors, and preventive and treating strategies.

Fluid Challenge During Anesthesia: A Systematic Review and Meta-analysis.

BACKGROUND: Assessing the volemic status of patients undergoing surgery is part of the routine management for the anesthesiologist. This assessment is commonly performed by means of dynamic indexes based on the cardiopulmonary interaction during mechanical ventilation (if available) or by administering a fluid challenge (FC). The FC is used during surgery to optimize predefined hemodynamic targets, the so-called Goal-Directed Therapy (GDT), or to correct hemodynamic instability (non-GDT). METHODS: In this systematic review, we considered the FC components in studies adopting either GDT or non-GDT, to assess whether differences exist between the 2 approaches. In addition, we performed a meta-analysis to ascertain the effectiveness of dynamic indexes pulse pressure variation (PPV) and stroke volume (SV) variation (SVV), in predicting fluid responsiveness. RESULTS: Thirty-five non-GDT and 33 GDT studies met inclusion criteria, including 5017 patients. In the vast majority of non-GDT and GDT studies, the FC consisted in the administration of colloids (85.7% and 90.9%, respectively). In 29 non-GDT studies, the colloid infused was the 6% hydroxyethyl starch (6% HES; 96.6% of this subgroup). In 20 GDT studies, the colloid infused was the 6% HES (66.7% of this subgroup), while in 5 studies was a gelatin (16.7% of this subgroup), in 3 studies an unspecified colloid (10.0% of this subgroup), and in 1 study albumin (3.3%) or, in another study, both HES 6% and gelatin (3.3%). In non-GDT studies, the median volume infused was 500 mL; the time of infusion and hemodynamic target to assess fluid responsiveness lacked standardization. In GDT studies, FC usually consisted in the administration of 250 mL of colloids (48.8%) in 10 minutes (45.4%) targeting an SV increase >10% (57.5%). Only in 60.6% of GDT studies, a safety limit was adopted. PPV pooled area under the curve (95% confidence interval [CI]) was 0.86 (0.80-0.92). The mean (standard deviation) PPV threshold predicting fluid responsiveness was 10.5% (3.2) (range, 8%-15%), while the pooled (95% CI) sensitivity and specificity were 0.80 (0.74-0.85) and 0.83 (0.73-0.91), respectively. SVV pooled area under the curve (95% CI) was 0.87 (0.81-0.93). The mean (standard deviation) SVV threshold predicting fluid responsiveness was 11.3% (3.1) (range, 7.5%-15.5%), while the pooled (95% CI) sensitivity and specificity were 0.82 (0.75-0.89) and 0.77 (0.71-0.82), respectively. CONCLUSIONS: The key components of FC including type of fluid (colloids, often 6% HES), volume (500 and 250 mL in non-GDT studies and GDT studies, respectively), and time of infusion (10 minutes) are quite standardized in operating room. However, pooled sensitivity and specificity of both PPV and SVV are limited.

Cardiac cycle efficiency and dicrotic pressure variations: new parameters for fluid therapy: An observational study.

BACKGROUND: During a fluid challenge, the changes in cardiac performance and peripheral circulatory tone are closely related to the position of the ventricle on the Frank-Starling curve. Some patients have a good haemodynamic response to a fluid challenge, others hardly any response. The early haemodynamic effects of a fluid challenge could predict the final response before the entire fluid volume has been administered. OBJECTIVE: To assess whether a multivariate logistic regression model, including pulse pressure variation (PPV), cardiac cycle efficiency (CCE), arterial elastance and the difference between the dicrotic pressure and both systolic and mean arterial pressure (SAP - Pdic and MAP - Pdic) can predict cardiac responsiveness early during a fluid challenge in comparison with the standard procedure described elsewhere. DESIGN: Observational study. SETTING: Elective surgical patients undergoing laparotomy, enrolled in two Italian University Hospitals. PATIENTS: Fifty adult surgical patients, ventilated with a lung protective strategy, were enrolled and data from 46 were analysed. INTERVENTIONS: A fluid challenge consisting of 500 ml of crystalloid infused over 10 min. MAIN OUTCOME MEASURES AND ANALYSIS: The changes in CCE, arterial elastance, SAP - Pdic and MAP - Pdic were compared using analysis of variance. A multivariate logistic regression analysis utilising baseline values and the first minute measuring a variation statistically significant for the considered variables. RESULTS: At baseline, PPV correctly identified 70% of patients (89% of non-responders; 42% of responders). The model, including baseline PPV, ΔCCE and ΔSAP - Pdic, correctly identified the efficiency of fluid challenge in 87% of patients (84.2% of responders; 92.5 of non-responders) after 5 min from fluid challenge infusion. CONCLUSION: In this pilot study conducted in a population of surgical patients mechanically ventilated with a VT less than 8 ml kg, a dynamic model of fluid challenge assessment, including PPV, ΔCCE and ΔSAP - Pdic, enhances the prediction of fluid challenge response after 5 min of a 10-min administration. TRIAL REGISTRATION: ACTRN12616001479493.

FloTrac/Vigileo(TM) (third generation) and MostCare(®)/PRAM versus echocardiography for cardiac output estimation in vascular surgery.

OBJECTIVE: To compare the FloTrac/Vigileo(TM) cardiac output (COFT/V) and the MostCare(®)/PRAM cardiac output (COMC/P) versus transthoracic echocardiographic cardiac output estimation (reference method; CO(ECHO)). DESIGN: Prospective observational study. SETTING: Single center, Cardio-Thoracic and Vascular Surgery/Intensive Care Unit. PARTICIPANTS: Patients undergoing elective vascular surgery. INTERVENTIONS: Cardiac output measurement with two pulse contour methods: the FloTrac/Vigileo(TM) and the MostCare(®)/PRAM before (T1) and after (T2) fluid loading versus echocardiography (reference method). MEASUREMENTS AND MAIN RESULTS: One hundred fifty-six CO measurements were performed in 26 patients. The data showed poor agreement between CO(ECHO) and CO(FT/V): r(2) = 0.29 (T1) and 0.27 (T2); bias -0.37 (T1) and -0.40 (T2) L/min; limits of agreement from -3.10 to 2.42 (T1) and from -3.0 to 2.2 (T2) L/min. The percentage error was 51.7% (T1) and 49.3% (T2). Conversely, COMC/P resulted in agreement with echocardiography: r(2) = 0.76 (T1) and 0.80 (T2); bias -0.01 (T1) and -0.06 (T2) L/min; limits of agreement from -1.13 to 1.11 (T1) and from -0.90 to 0.80 (T2) L/min, with a PE of 22.4% (T1) and of 17.0% (T2). CONCLUSIONS: In patients undergoing vascular surgery, the FloTrac/Vigileo(TM) did not demonstrate that it was a reliable system for CO monitoring when compared with echocardiography-derived CO. However, MostCare(®)/PRAM was shown to estimate CO with a good level of agreement with echocardiographic measures.