Pearl, Ronald G.

While the field of anesthesiology has a storied history of innovation, especially related to patient safety, contemporary anesthesiologists face growing barriers to innovation from complex regulatory requirements and financial constraints. The Biodesign framework offers a systematic approach to medical technology development that can be applied to the perioperative space to address these challenges. This process begins with identification and screening of high-value clinical needs, followed by generation and evaluation of potential solutions, and culminates in strategy development, business planning, and fundraising. Each stage is designed to guide clinicians from early observation through translation into viable technologies. By adopting this structured method, anesthesiologists are well-positioned to transform clinical insights into scalable solutions, ensuring the specialty continues to advance patient safety and care in the face of evolving clinical demands.

OBJECTIVE: Volatile anesthetics (VAs) are gaining renewed interest as a sedation strategy in the intensive care, offering an alternative to traditional IV agents. VAs provide several pharmacologic advantages, including rapid onset and offset, minimal systemic metabolism, and favorable recovery profiles. Advances in delivery systems enabled the safe and practical administration of volatile agents in the ICU. Thus, we aimed to describe the pharmacology and safety aspects of inhaled agents as well as the systems designed to deliver VAs in the ICU. DATA SOURCES: Relevant literature was identified through PubMed and MEDLINE databases. STUDY SELECTION: Original research, review articles, commentaries, and guidelines addressing safety, efficacy, and use of VAs in adult ICU patients were included. DATA EXTRACTION: Studies were reviewed by the authors, with key findings summarized and organized by pharmacologic properties, delivery systems, and safety domains. DATA SYNTHESIS: VAs are halogenated hydrocarbons whose mechanism of action is not fully understood. Although the CNS is the primary site of action, the end-tidal concentration of exhaled anesthetic is used to monitor clinical effects such as immobility to a noxious stimulus. Inhaled agents have unique pharmacokinetics, minimal metabolisms, and distinct recovery. The side effect profile is also unique, with malignant hyperthermia being the most feared, yet rare complication. Two systems for inhalational sedation delivery are available internationally, with one currently under evaluation in the United States. The systems are composed of a miniature vaporizer, delivery controller, and a monitor. The systems have distinct safety considerations, such as tidal volume limits. CONCLUSIONS: VAs can be used as sedative agents in the ICU. This article comprehensively reviews the pharmacology of VAs along with their safety profile and describes the structure and function of miniature vaporizers currently available on the world market.

Background: Transfusion has a persistent low risk of transfusion-transmitted infection and transfusion-associated graft- versus -host disease that may be addressed using pathogen reduction. The Red Cell Pathogen Inactivation (ReCePI) trial tested whether amustaline/glutathione pathogen-reduced red cells are noninferior to conventional transfusions for support of acute surgical blood loss. Methods: A phase 3, double-blinded, noninferiority trial randomized cardiac or thoracic–aorta surgery patients with increased risk of red cell transfusion to receive pathogen-reduced or conventional red cells during and for 7 days postsurgery. The primary endpoint was the proportion of patients with acute kidney injury (AKI), which is defined as an increase from baseline of greater than or equal to 0.3 mg/dl serum creatinine within 48 h of surgery. Noninferiority was claimed if the upper bound 95% CI of the treatment difference was less than half (50%) of the observed conventional arm incidence. Adverse events and treatment-emergent red cell antibodies were assessed for 28 and 75 days, respectively. Results: A total of 581 subjects were randomized, and 321 (55%) were transfused with study red cells. Transfused subjects in both arms had similar baseline demographics, medical histories, hemoglobin levels, and surgical procedures. Hemoglobin day 3 nadir levels (8.6 g/dl [7.8 to 9.2] in the pathogen-reduced arm; 8.4 g/dl [7.8 to 9.3] in the conventional arm; P = 0.52) were comparable. Incidence of AKI by 48 h was 46 of 157 (29.3%) in the pathogen-reduced arm and 45 of 161 (28.0%) in the conventional arm (treatment difference, 0.7%; 95% CI, −8.9 to 10.4%; noninferiority margin, 14.0%; P = 0.001 for noninferiority). AKI within 7 days by Kidney Disease Improving Global Outcomes staging criteria was not different (59 of 159 [37.1%] in the pathogen-reduced arm; 55 of 162 [34.0%] in the conventional arm; P = 0.53), but stage III was more common in the pathogen-reduced arm (pathogen-reduced arm, 15 of 159 [9.4%]; conventional arm, 7 of 162 [4.3%]; P = 0.075). Of 159 pathogen-reduced red cell recipients, 5 (3.1%) developed specific, low-titer antibodies without evidence of hemolysis. Conclusions: The incidence of AKI in recipients of pathogen-reduced red cells was noninferior to conventional red cell transfusion. Treatment-emergent antibodies were uncommon and not clinically significant.

Objective Specific sedative hypnotic agents, administered to facilitate endotracheal intubation (ETI) in critically ill adults, may lead to adverse outcomes such as peri-intubation cardiovascular collapse. However, little is known from systematic investigations of the impact these individual agents have on cardiovascular function or other clinical outcomes. Data sources MEDLINE, Embase, CENTRAL, ClinicalTrials.gov, Scopus and Web of science databases. Study selection We conducted a systematic search for randomized and non-randomized studies that evaluated adult (≥18 years) critically ill patients who were sedated to facilitate ETI with ketamine, propofol, ketamine/propofol, etomidate, or a benzodiazepine and who had data on peri-intubation hemodynamics and at least one other outcome involving acute kidney injury, delirium, opioid use, intubation difficulty, sequential organ failure assessment, length of stay, or mortality. Eighty-five studies were identified for eligibility assessment with 23 included in the analysis. Data extraction Two reviewers independently screened articles, extracted data from selected articles, and assessed risk of bias using ROBINS-I for observational studies and revised Cochrane Risk of Bias tool for randomized controlled trials. Data synthesis Acute cardiovascular dysfunction (peri-intubation hemodynamic instability and/or cardiac arrest) was similar between etomidate and ketamine with more events seen when propofol versus non-propofol sedation was administered. However, exploratory meta-analysis demonstrated no difference between etomidate and ketamine (OR 1.05 [95%CI 0.60-1.84]) or between etomidate and propofol (OR 0.91 [95%CI 0.33-2.46]). Compared to ketamine, etomidate demonstrated lower survival to hospital discharge in the included studies in exploratory meta-analysis OR 0.76 (95%CI 0.62-0.92). Limited data existed for other outcomes with no discernible differences between sedative agents. Conclusions Acute cardiovascular dysfunction was more common when propofol, as compared to non-propofol sedation, was administered, although not statistically significant in exploratory meta-analysis. In addition, etomidate conferred lower survival to hospital discharge versus non-etomidate sedation, which was confirmed in exploratory meta-analysis of etomidate versus ketamine.

AbstractBackgroundThe clinical significance of natural and treatment‐emergent antibodies specific for amustaline/glutathione pathogen‐reduced red blood cells (PRRBCs) is not known.Study Design and MethodsA Phase 3, randomized clinical trial of PRRBCs (ReCePI) compared PRRBCs with conventional RBCs in cardiac or thoracic‐aorta surgery. Subjects transfused during and for 7 days after surgery were screened for PRRBC‐specific antibodies at baseline, 28 and 75 days post‐surgery. Subjects with treatment‐emergent antibodies were assessed for evidence of hemolysis. Cryopreserved subject RBC samples were assayed by flow cytometry for circulating PRRBCs using an acridine‐specific (2S197‐2M1) monoclonal antibody, and for human IgG‐coated RBCs. RBC‐surface acridine density was quantitated using a commercial calibrated phycoerythrin (PE)‐bead panel.ResultsFive of 159 (3.1%) PRRBC and zero of 162 conventional RBC recipients developed treatment‐emergent PRRBC‐specific IgG, low titer antibodies detected 26–80 days post‐surgery after exposure to 1–3 PRRBC units, without clinical evidence of hemolysis. DAT and eluate were weak (w+) positive and PRRBC‐specific in one subject. A monocyte monolayer assay (MMA) was non‐reactive in the three subjects with an interpretable result. Flow cytometry demonstrated circulating PRRBCs in all five subjects expressing surface acridine concentrations at the limit of detection (approximately 150–301 PE molecules/RBC) compared with freshly transfused PRRBCs (approximately 7500 PE molecules/RBC). In some samples, loss of surface acridine expression could not be distinguished from clearance of the PRRBCs.DiscussionTreatment‐emergent PRRBC‐specific antibodies with the characteristics of nonclinically significant antibodies were detected in five subjects transfused with PRRBCs. Flow cytometry demonstrated persistent circulating PRRBCs with minimal surface acridine expression. (www.ClinicalTrials.gov Identifier NCT03459287).

Introduction: Red blood cell (RBC) transfusion is a lifesaving intervention with a low but persistent risk of transfusion-transmitted infection. Amustaline/glutathione RBC pathogen-reduction (PR) technology is designed to proactively inactivate a broad spectrum of viruses, bacteria, protozoa and leukocytes by chemically crosslinking nucleic acids and preventing replication and transcription. The Red Cell Pathogen Inactivation (ReCePI) trial was a Phase III, double-blinded, randomized non-inferiority study comparing PR and conventional RBCs for the support of acute anemia. Methods/Study Design: Complex cardiac or thoracic-aorta surgery patients received conventional (Control) or PR RBCs (Test) during and for 7 days after surgery. The protocol was conducted with ethics committee approval at all participating centers and written informed consent from all participants. Hemoglobin levels, blood utilization and serum creatinine were assessed as indicators of efficacy and oxygenation of tissues (Karkouti et al. Br J Anaesth. 2012; 109 Suppl 1: i29-i38). The primary endpoint was the incidence of acute kidney injury (AKI) measured as change in serum creatinine from baseline within 48 hours of surgery, a predictor of adverse postoperative outcomes including mortality by Day 30 post-surgery (Lassnig et al. Am Soc Nephrol 2004; 1597-1605). Secondary endpoints included AKI occurring up to 7 days post-surgery (KDIGO Clinical Practice Guideline for AKI, Kidney Inter, Suppl. 2012;2:1-138); death or the need for renal replacement therapy by 30 days post-surgery; PR RBC-specific antibodies; and death by day 75 post-surgery. With >292 subjects enrolled, the study had 80% power to demonstrate non-inferiority, assuming an AKI incidence of 30% with conventional RBCs and a non-inferiority margin of half the conventional RBC rate. Under these circumstances, an absolute treatment increase of 5% in the AKI rate in the PR RBC arm would fail the non-inferiority test. This work was supported by a contract with the US Biomedical Advanced Research and Development Authority (HHS010020160009c) with Cerus Corporation. Results: Five-hundred and eighty-one subjects were randomized and 321 (55%) transfused in 18 US hospitals. In the modified intent-to-treat analysis subjects receiving Test and Control RBCs had similar median [IQR] total blood loss (1500 [940-2475] mL Test, 1733 [1060-2880] mL Control, p=0.310) and comparable median hemoglobin levels at baseline and immediately post-surgery (9.8 [8.9-10.9] g/dL Test, 9.6 [8.6-10.6] g/dL Control, p=0.157) and for 7 days after surgery, The PR RBC arm was transfused with fewer RBCs, measured as total RBC Hb transfused over 7-days (169.0 [102.0-240.0] g Hb PR arm, 188.0 [126.0-295.0] g Hb, conventional RBC arm, p=0.008). The incidence of AKI was 29.3% (46/157) for Test and 28.0% (45/161) for Control. The treatment difference was 0.74% (95% CI -8.9, 10.4%, non-inferiority margin 14.0%, p=0.001 for non-inferiority). Non-inferiority was also achieved by the per protocol analysis. Average mean change in serum creatinine within 48 hours of surgery was comparable (Test 0.020, Control 0.23 mg/dL, P=0.515). Adverse events, serious adverse events and deaths on study were not different. Five of 159 (3.1%) PR RBC recipients developed low titer PR RBC-specific antibodies without clinical signs of hemolysis. Flow cytometry analysis revealed persistent circulating PR RBCs with uniform antigen loss (modulation). Low level human IgG antibody binding was demonstrated in 3 of 5 subjects. Conclusions: PR RBCs showed equivalent hemoglobin support for acute bleeding patients undergoing cardiac or thoracic-aorta surgery while using less transfused total RBC Hb over 7 days. The incidence of AKI in patients transfused with PR RBCs was non-inferior to that observed with conventional RBCs, indicative of effective tissue oxygenation. Treatment-related antibodies to PR-RBC were observed only in Test subjects, the antibodies were low titer, transient, without clinical hemolysis, and persistent circulating PR RBCs were detected with modulated low level acridine antigen expression (www.clinicaltrials.gov #NCT03459287).

Abstract Background Red blood cell (RBC) transfusion is a critical supportive therapy in cardiovascular surgery (CVS). Donor selection and testing have reduced the risk of transfusion-transmitted infections; however, risks remain from bacteria, emerging viruses, pathogens for which testing is not performed and from residual donor leukocytes. Amustaline (S-303)/glutathione (GSH) treatment pathogen reduction technology is designed to inactivate a broad spectrum of infectious agents and leucocytes in RBC concentrates. The ReCePI study is a Phase 3 clinical trial designed to evaluate the efficacy and safety of pathogen reduced RBCs transfused for acute anemia in CVS compared to conventional RBCs, and to assess the clinical significance of treatment-emergent RBC antibodies. Methods ReCePI is a prospective, multicenter, randomized, double-blinded, active-controlled, paralleldesign, non-inferiority study. Eligible subjects will be randomized up to 7 days before surgery to receive either leukoreduced Test (pathogen reduced) or Control (conventional) RBCs from surgery up to Day 7 post-surgery. The primary efficacy endpoint is the proportion of patients transfused with at least one study transfusion with an acute kidney injury (AKI) diagnosis defined as any increased serum creatinine (sCr) level ≥0.3 mg/dL (or 26.5 µmol/L) from presurgery baseline within 48±4 hours of the end of surgery. The primary safety endpoints are the proportion of patients with any treatment-emergent adverse events (TEAEs) related to study RBC transfusion through 28 days, and the proportion of patients with treatment-emergent antibodies with confirmed specificity to pathogen reduced RBCs through 75 days after the last study transfusion. With ≥292 evaluable, transfused patients (>146 per arm), the study has 80% power to demonstrate non-inferiority, defined as a Test group AKI incidence increase of no more than 50% of the Control group rate, assuming a Control incidence of 30%. Discussion RBCs are transfused to prevent tissue hypoxia caused by surgery-induced bleeding and anemia. AKI is a sensitive indicator of renal hypoxia and a novel endpoint for assessing RBC efficacy. The ReCePI study is intended to demonstrate the non-inferiority of pathogen reduced RBCs to conventional RBCs in the support of renal tissue oxygenation due to acute anemia and to characterize the incidence of treatment-related antibodies to RBC.