Amino Acid Infusion for Perioperative Functional Renal Protection: A Meta-analysis.

OBJECTIVES: Acute kidney injury (AKI) is a common perioperative complication. To date, no single intervention has been proven effective for AKI prevention in this setting. However, intravenous amino acids (AA) administration may recruit renal functional reserve and, thereby, attenuate the perioperative loss of the glomerular filtration rate. DESIGN: We performed a meta-analysis to assess the efficacy of AA infusion for perioperative renal functional protection. SETTING AND PARTICIPANTS: We performed a meta-analysis of controlled studies in perioperative patients evaluating intravenous AA infusion versus any comparator. MEASUREMENTS: The primary outcome was AKI at longest follow-up. We performed a random effects meta-analysis on the relative risk (RR) scale to assess the effect of AA infusion. We used a Bayesian approach to estimate the probability of benefit (RR < 1) for the primary outcome. Secondary outcomes included renal replacement therapy, serum creatinine, and estimated glomerular filtration rate. Tertiary outcomes included mechanical ventilation duration, intensive care unit and hospital length of stay and mortality (PROSPERO: CRD42024547225). RESULTS: We identified 15 studies (14 randomized controlled trials and 1 prospective before-after study) reporting at least one outcome of interest (4,544 patients), with 6 studies (4,084 patients) reporting the primary outcome. AKI occurred 504 of 2,041 (24.7%) in AA patients versus 614 of 2,041 (30.1%) in controls (RR, 0.66; 95% confidence interval, 0.47-0.94; I2 = 50%; p = 0.02), which corresponded with a 99.1% probability of AKI reduction with AA. Moreover, consistent with these findings, AA decreased serum creatinine and hospital length of stay and increased the estimated glomerular filtration rate. CONCLUSIONS: This meta-analysis suggests that AA administration likely decreased the perioperative incidence of AKI.

Protective hemodynamics: a novel strategy to manage blood pressure.

PURPOSE OF REVIEW: This editorial aims to highlight the evolving concept of protective hemodynamics in the management of critically ill patients. RECENT FINDINGS: Recent literature underscores the limitations of rigid blood pressure targets, particularly in the context of critical care and perioperative management. High blood pressure targets, especially when coupled with high-dose vasopressors, can lead to poor outcomes. 'Protective hemodynamics' aims to maintain cardiovascular stability while reducing risks associated with interventions. SUMMARY: The implications of adopting protective hemodynamics are profound for both clinical practice and research. Clinically, this approach can reduce iatrogenic harm and improve long-term outcomes for critically ill patients. For research, it opens new avenues for investigating individualized hemodynamic management strategies that prioritize overall patient stability and long-term health over rigid target attainment.

Extracorporeal membrane oxygenation for prevention of barotrauma in patients with respiratory failure: A scoping review.

BACKGROUND: Barotrauma is a frequent complication in patients with severe respiratory failure and is associated with poor outcomes. Extracorporeal membrane oxygenation (ECMO) implantation allows to introduce lung-protective ventilation strategies that limit barotrauma development or progression, but available data are scarce. We performed a scoping review to summarize current knowledge on this therapeutic approach. METHODS: We systematically searched PubMed/MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials for studies investigating ECMO as a strategy to prevent/limit barotrauma progression in patients with respiratory failure. Pediatric studies, studies on perioperative implantation of ECMO, and studies not reporting original data were excluded. The primary outcome was the rate of barotrauma development/progression. RESULTS: We identified 21 manuscripts presenting data on a total of 45 ECMO patients. All patients underwent veno-venous ECMO. Of these, 21 (46.7%) received ECMO before invasive mechanical ventilation. In most cases, ECMO implantation allowed to modify the respiratory support strategy (e.g., introduction of ultraprotective/low pressure ventilation in 12 patients, extubation while on ECMO in one case, and avoidance of invasive ventilation in 15 cases). Barotrauma development/progression occurred in <10% of patients. Overall mortality was 8/45 (17.8%). CONCLUSION: ECMO implantation to prevent barotrauma development/progression is a feasible strategy and may be a promising support option.

Mechanical left ventricular unloading in cardiogenic shock treated with venoarterial extracorporeal membrane oxygenation: a systematic review and meta-analysis.

OBJECTIVE: To evaluate if mechanical left ventricular unloading could reduce mortality in patients with cardiogenic shock undergoing venoarterial extracorporeal membrane oxygenation (VA-ECMO). METHODS: We searched MEDLINE, Embase, and the Cochrane Library for randomized controlled trials and propensity score-matched studies published until December 20, 2023. The primary outcome was mortality at the longest follow-up. We used a Mantel-Haenszel random effects meta-analysis and reported the pooled results with a risk ratio (RR) and 95% confidence interval (CI). The review protocol was registered on PROSPERO International prospective register of systematic review (CRD42024498665). RESULTS: We identified two randomized controlled trials and eleven propensity score-matched studies, totaling 9858 patients. Mechanical left ventricular unloading was significantly associated with reduced mortality at the longest follow-up (RR, 0.89; 95% CI, 0.84-0.94; P = 0.0001; moderate certainty of evidence), which was confirmed in studies using intraaortic ballon pump (IABP). Benefits of mechanical unloading were also observed in terms of successful VA-ECMO weaning (RR, 1.15; 95% CI, 1.02-1.29; P = 0.02; low certainty of evidence) and favorable neurological outcome (two studies; RR, 2.45; 95% CI, 1.62-3.69; P < 0.0001; low certainty of evidence), although we observed an increased incidence of major bleeding (RR, 1.27; 95% CI, 1.02-1.59; P = 0.03; low certainty of evidence) and hemolysis (RR, 1.49; 95% CI, 1.10-2.02; P = 0.01; moderate certainty of evidence). CONCLUSIONS: Among adult patients with cardiogenic shock treated with VA-ECMO, mechanical left ventricular unloading was associated with reduced mortality, which was confirmed in studies using IABP as an unloading device.

The use of angiotensin II for the management of distributive shock: expert consensus statements.

BACKGROUND: Despite the growing body of evidence supporting the use of angiotensin II (ATII) in distributive shock, its integration into existing treatment algorithms requires careful consideration of factors related to patient comorbidities, hemodynamic parameters, cost-effectiveness, and risk-benefit balance. Moreover, several questions regarding its use in clinical practice warrant further investigations. To address these challenges, a group of Italian intensive care specialists (the panel) developed a consensus process using a modified Delphi technique. METHODS: The panel defined five clinical questions during an online scoping workshop and then provided a short list of statements related to each clinical question based on literature review and clinical experience. A total of 20 statements were collected. Two coordinators screened and selected the final list of statements to be included in the online survey, which consisted of 17 statements. The consensus was reached when ≥ 75% of respondents assigned a score within the 3-point range of 1-3 (disagreement) or 7-9 (agreement). RESULTS: Overall, a consensus on agreement was reached on 13 statements defining the existing gaps in scientific evidence, the possibility of evaluating the addition of drugs with different mechanisms of action for the treatment of refractory shock, the utility of ATII in reducing the catecholamine requirements in the treatment of vasopressor-resistant septic shock, and the effectiveness of ATII in treating patients in whom angiotensin-converting enzyme activity is reduced or pharmacologically blocked. It was widely shared that renin concentration can be used to identify patients who most likely benefit from ATII to restore vascular tone. Thus, the patients who might benefit most from using ATII were defined. Lastly, some potential barriers to the use of ATII were described. CONCLUSIONS: ATII was recognized as a useful treatment to reduce catecholamine requirements in treating vasopressor-resistant septic shock. At the same time, the need for additional clinical trials to further elucidate the efficacy and safety of ATII, as well as investigations into potential mechanisms of action and optimization of treatment protocols in patients with refractory distributive shock, emerged.

The Effects of Corticosteroids on Survival in Pediatric and Nonelderly Adult Patients Undergoing Cardiac Surgery: A Meta-analysis of Randomized Studies.

OBJECTIVE: Cardiac surgery can be complicated by the development of a systemic inflammatory response syndrome related to cardiopulmonary bypass. This potentially contributes to the occurrence of postoperative morbidity and mortality. Corticosteroids can be used to reduce such inflammation, but the overall balance between potential harm and benefit is unknown and may be age-dependent. The present meta-analysis aims to evaluate the effects of prophylactic corticosteroids in pediatric and non-elderly adult cardiac surgery patients. DESIGN: Systematic review and meta-analysis of randomized trials. SETTING: Cardiac surgery with cardiopulmonary bypass. PARTICIPANTS: Patients younger than 65 years old (pediatric and non-elderly adults). INTERVENTIONS: Perioperative use of corticosteroids versus placebo or standard care. MEASUREMENTS AND MAIN RESULTS: Two independent investigators searched PubMed, EMBASE and the Cochrane Library from inception to January 20, 2024. The primary outcome was mortality at the longest follow-up available. Secondary outcomes included acute kidney injury, atrial fibrillation, myocardial injury, cerebrovascular events, and infections. Our search strategy identified a total of 17 randomized trials involving 6,598 patients. Mortality was significantly reduced in the corticosteroid group (78/3321 [2.3%] vs. 116/3277 [3.5%]; risk ratio = 0.69; 95% confidence interval, 0.52 to 0.92; P = 0.01; I2 = 0%; NNT = 91). Moreover, the highest postoperative vasoactive inotropic score (VIS) was significantly lower in corticosteroid group (MD: -2.07, 95% CI -3.69 to -0.45, P = 0.01, I2 = 0%). No significant differences in secondary outcomes between the two treatment groups were recorded. CONCLUSIONS: This meta-analysis of randomized trials highlights the potential benefits of corticosteroids on survival in cardiac surgery for patients younger than 65 years old.

Protamine and Heparin Interactions: A Narrative Review.

ABSTRACT: Protamine, first isolated from salmon fish sperm and now produced through recombinant biotechnology, is an antidote that neutralizes the anticoagulant properties of heparin. Protamine function is based on the capacity to dissociate the heparin-antithrombin III (AT III) complex (an important link that promotes blood fluidification by inhibiting coagulation), forming the inactive heparin-protamine complex. Protamine has itself dose-dependent anticoagulant properties: It interferes with coagulation factors and platelet function; it stimulates fibrinolysis; it can lead to thrombocytopenia and reduction in thrombin-related platelet aggregation; it decreases platelet response to thrombin receptor agonist in a dose-dependent manner. In this review, we will focus on protamine and its interaction with heparin. Notably, protamine is able to antagonize not only unfractionated heparin (UFH) but also low molecular weight heparins to various degrees. Protamine-allergic and anaphylactoid systemic reactions may affect up to 1 in 10 people and should be prevented and treated early.

Sevoflurane multiple Wash In/Wash Out at the end of anesthesia to reduce agitation: A multicenter double-blind randomized controlled trial.

Background: Postoperative agitation is common after non-cardiac surgery. It is associated with postoperative delirium and cognitive dysfunction, leading to prolonged hospital stay and delayed social readjustment. Prevention and treatment strategies are lacking. We assessed the efficacy of a novel approach, the Wash In/Wash Out procedure, in reducing post-anesthetic agitation. Methods: This multicenter, parallel-group, double-blind randomized controlled trial is enrolling 200 patients undergoing open abdominal surgery. Participants are randomly assigned to either a control group receiving standard recovery methods or an investigational group undergoing the Wash In/Wash Out procedure. In the Wash In/Wash Out procedure group, sevoflurane is stopped and then promptly restarted when the patient shows the first signs of awakening to achieve an end-tidal concentration of 1 minimum alveolar concentration (MAC) for 5 min. This stop-and-restart cycle is performed three times. The trial's primary outcome is the rate of postoperative agitation. Secondary outcomes include rate of postoperative delirium and cognitive dysfunction, postoperative nausea and vomiting, and length of intensive care and hospital stay. Discussion: The OPERA trial investigates the effect of the Wash In/Wash Out procedure to reduce post-anesthetic agitation in non-cardiac surgery. This study could offer a significant contribution to improving patient outcomes and optimizing recovery protocols in surgical settings.

A Randomized Trial of Intravenous Amino Acids for Kidney Protection.

BACKGROUND: Acute kidney injury (AKI) is a serious and common complication of cardiac surgery, for which reduced kidney perfusion is a key contributing factor. Intravenous amino acids increase kidney perfusion and recruit renal functional reserve. However, the efficacy of amino acids in reducing the occurrence of AKI after cardiac surgery is uncertain. METHODS: In a multinational, double-blind trial, we randomly assigned adult patients who were scheduled to undergo cardiac surgery with cardiopulmonary bypass to receive an intravenous infusion of either a balanced mixture of amino acids, at a dose of 2 g per kilogram of ideal body weight per day, or placebo (Ringer's solution) for up to 3 days. The primary outcome was the occurrence of AKI, defined according to the Kidney Disease: Improving Global Outcomes creatinine criteria. Secondary outcomes included the severity of AKI, the use and duration of kidney-replacement therapy, and all-cause 30-day mortality. RESULTS: We recruited 3511 patients at 22 centers in three countries and assigned 1759 patients to the amino acid group and 1752 to the placebo group. AKI occurred in 474 patients (26.9%) in the amino acid group and in 555 (31.7%) in the placebo group (relative risk, 0.85; 95% confidence interval [CI], 0.77 to 0.94; P = 0.002). Stage 3 AKI occurred in 29 patients (1.6%) and 52 patients (3.0%), respectively (relative risk, 0.56; 95% CI, 0.35 to 0.87). Kidney-replacement therapy was used in 24 patients (1.4%) in the amino acid group and in 33 patients (1.9%) in the placebo group. There were no substantial differences between the two groups in other secondary outcomes or in adverse events. CONCLUSIONS: Among adult patients undergoing cardiac surgery, infusion of amino acids reduced the occurrence of AKI. (Funded by the Italian Ministry of Health; PROTECTION ClinicalTrials.gov number, NCT03709264.).

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.

Norepinephrine Salt Formulations and Risk of Therapeutic Error: Results of a National Survey.

OBJECTIVES: Norepinephrine is available commercially in solution containing its salt (eg, tartrate), but only the base form (ie, norepinephrine base) is active pharmacologically. Unfortunately, the outer label of drug packages frequently reports the dosage of norepinephrine as a salt, which can lead potentially to therapeutic errors when prescribing norepinephrine. We performed a survey to assess the level of awareness of this issue. DESIGN: National survey. SETTING: Acute care units of Italian hospitals. PARTICIPANTS: Acute care physicians and nurses. INTERVENTIONS: A 15-item online survey was emailed to 305 critical care practitioners in Italy. Questions included information on the participants' background, methods of diluting norepinephrine, interpretation of recommended doses from guidelines, and a sample case related to the preparation and administration of the drug. MEASUREMENTS AND MAIN RESULTS: We collected 106 responses from 54 hospitals. All hospitals used norepinephrine bitartrate salt. Of the participants, 53% responded that the guidelines express norepinephrine dosages as a salt, 23% as the base form, and 24% were unsure or unaware about it. The simulated patient-dose calculation was resolved in 81% of cases with an incorrect calculation referring to the norepinephrine salt and only in 19% referring to the norepinephrine base. CONCLUSIONS: There is significant variability in dosage management of norepinephrine across different hospital units, as well as a lack of knowledge regarding the salt-to-base ratio. Scientific publications (eg, guidelines) should specify whether they are referring to the base or salt form of norepinephrine. The adoption of different labeling and national standards for dilution may decrease the risk of therapeutic errors.

Comparison between propofol and total inhalational anaesthesia on cardiovascular outcomes following on-pump cardiac surgery in higher-risk patients: a randomised controlled pilot and feasibility study.

OBJECTIVES: Myocardial revascularisation and cardiopulmonary bypass (CPB) can cause ischaemia-reperfusion injury, leading to myocardial and other end-organ damage. Volatile anaesthetics protect the myocardium in experimental studies. However, there is uncertainty about whether this translates into clinical benefits because of the coadministration of propofol and its detrimental effects, restricting myocardial protective processes. METHODS: In this single-blinded, parallel-group randomised controlled feasibility trial, higher-risk patients undergoing elective coronary artery bypass graft (CABG) surgery with an additive European System for Cardiac Operative Risk Evaluation ≥5 were randomised to receive either propofol or total inhalational anaesthesia as single agents for maintenance of anaesthesia. The primary outcome was the feasibility of recruiting and randomising 50 patients across two cardiac surgical centres, and secondary outcomes included the feasibility of collecting the planned perioperative data, clinically relevant outcomes and assessments of effective patient identification, screening and recruitment. RESULTS: All 50 patients were recruited within 11 months in two centres, allowing for a 13-month hiatus in recruitment due to the COVID-19 pandemic. Overall, 50/108 (46%) of eligible patients were recruited. One patient withdrew before surgery and one patient did not undergo surgery. All but one completed in-hospital and 30-day follow-up. CONCLUSIONS: It is feasible to recruit and randomise higher-risk patients undergoing CABG surgery to a study comparing total inhalational and propofol anaesthesia in a timely manner and with high acceptance and completion rates. TRIAL REGISTRATION NUMBER: NCT04039854.

Use of defibrotide in COVID-19 pneumonia: comparison of a phase II study and a matched real-world cohort control.

The coronavirus disease 2019 (COVID-19) pandemic led to an unprecedented burden on healthcare systems around the world and a severe global socioeconomic crisis, with more than 750 million confirmed cases and at least 7 million deaths reported by December 31, 2023. The DEFI-VID19 study (clinicaltrials gov. Identifier: NCT04335201), a phase II, single-arm, multicenter, open-label trial was designed in mid-2020 to assess the safety and efficacy of defibrotide in treating patients with COVID-19 pneumonia. Defibrotide was administered at a dose of 25 mg/kg intravenously, divided into four daily doses over a planned 14-day period for patients with COVID-19 pneumonia receiving non-invasive ventilation. The primary endpoint was respiratory failure-free survival (RFFS). Overall survival (OS), the number of post-recovery days, and adverse events were the secondary endpoints. For comparison, a contemporaneous control cohort receiving standard of care only was retrospectively selected by applying the eligibility criteria of the DEFI-VID19 trial. To adjust for the imbalance between the two cohorts in terms of baseline variable distributions, an outcome regression analysis was conducted. In adjusted analysis, patients receiving defibrotide reported a trend towards higher RFFS (hazard ratio [HR]=0.71; 95% confidence interval [CI]: 0.34-1.29; P=0.138) and OS (HR=0.78; 95% CI: 0.33-1.53; P=0.248]) and showed a significantly increased number of post-recovery days (difference in means =3.61; 95% CI: 0.97-6.26; P=0.0037). Despite concomitant thromboprophylaxis with low molecular weight heparin, the safety profile of defibrotide proved to be favorable. Taken together, our findings suggest that defibrotide may represent a valuable addition to the COVID-19 therapeutic options.

Renin in critically ill patients.

The renin-angiotensin system (RAS) constitutes one of the principal mechanisms to maintain hemodynamic and fluid homeostasis. However, most research until now on RAS primarily focuses on its relationship with hypertension and its role in critically ill hypotensive populations is not well understood. With the approval of angiotensin II (Ang II) in the United States and Europe, following a phase 3 randomized controlled trial showing efficacy in catecholamine-resistant vasodilatory shock, there is growing interest in RAS in critically ill patients. Among the fundamental components of RAS, renin acts as the initial stimulus for the entire system. In the context of hypotension, its release increases in response to low blood pressure sensed by renal baroreceptors and attenuated negative Ang II feedback loop. Thus, elevated renin could reflect disease severity and predict poor outcomes. Studies investigating this hypothesis have validated the prognostic accuracy of renin in various critically ill populations, with several reports indicating its superiority to lactate for mortality prediction. Accordingly, renin reduction has been used to assess the effectiveness of Ang II administration. Furthermore, renin holds potential to identify patients who might benefit from Ang II treatment, potentially paving the way for personalized vasopressor management. Despite these promising data, most available evidence is derived from retrospective analysis and necessitates prospective confirmation. The absence of a rapid, point-of-care and reliable renin assay presents another hurdle to its integration into routine clinical practice. This narrative review aims to describe the current understanding and future directions of renin as a biomarker during resuscitation of critically ill patients.