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ObjectivesTo determine in patients with acute respiratory distress syndrome (ARDS) on venovenous extracorporeal membrane oxygenation (VV ECMO) whether reducing driving pressure (ΔP) would decrease plasma biomarkers of inflammation and lung injury (interleukin-6 [IL-6], IL-8, and the soluble receptor for advanced glycation end-products sRAGE).DesignA single-center prospective physiologic study.SettingAt a single university medical center.ParticipantsAdult patients with severe COVID-19 ARDS on VV ECMO.InterventionsParticipants on VV ECMO had the following biomarkers measured: (1) pre-ECMO with low-tidal-volume ventilation (LTVV), (2) post-ECMO with LTVV, (3) during low-driving-pressure ventilation (LDPV), (4) after 2 hours of very low driving-pressure ventilation (V-LDPV, main intervention ΔP=1 cmH2O), and (5) 2 hours after returning to LDPV.Main measurements and resultsTwenty-six participants were enrolled; 21 underwent V-LDPV. There was no significant change in IL-6, IL-8, and sRAGE from LDPV to V-LDPV and from V-LDPV to LDPV. Only participants (9 of 21) with nonspontaneous breaths had significant change (p < 0.001) in their tidal volumes (Vt) (mean ± SD), 1.9 ± 0.5, 0.1 ± 0.2, and 2.0 ± 0.7 mL/kg predicted body weight (PBW). Participants with spontaneous breathing, Vt were unchanged-4.5 ± 3.1, 4.7 ± 3.1, and 5.6 ± 2.9 mL/kg PBW (p=0.481 and p=0.065, respectively). There was no relationship found when accounting for Vt changes and biomarkers.ConclusionsBiomarkers did not significantly change with decreased ΔPs or Vt changes during the first 24 hours post-ECMO. Despite deep sedation, reductions in Vt during V-LDPV were not reliably achieved due to spontaneous breaths. Thus, patients on VV ECMO for ARDS may have higher Vt (ie, transpulmonary pressure) than desired despite low ΔPs or Vt.

Background Increased inflammation has been well defined in coronavirus disease 2019 (COVID-19), while definitive pathways driving severe forms of this disease remain uncertain. Neutrophils are known to contribute to immunopathology in infections, inflammatory diseases, and acute respiratory distress syndrome, a primary cause of morbidity and mortality in COVID-19. Changes in neutrophil function in COVID-19 may give insight into disease pathogenesis and identify therapeutic targets. Methods Blood was obtained serially from critically ill COVID-19 patients for 11 days. Neutrophil extracellular trap formation (NETosis), oxidative burst, phagocytosis, and cytokine levels were assessed. Lung tissue was obtained immediately postmortem for immunostaining. PubMed searches for neutrophils, lung, and COVID-19 yielded 10 peer-reviewed research articles in English. Results Elevations in neutrophil-associated cytokines interleukin 8 (IL-8) and interleukin 6, and general inflammatory cytokines IFN-inducible protien-19, granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin 1β, interleukin 10, and tumor necrosis factor, were identified both at first measurement and across hospitalization (P Conclusions Literature to date demonstrates compelling evidence of increased neutrophils in the circulation and lungs of COVID-19 patients. Importantly, neutrophil quantity and activation correlates with severity of disease. Similarly, our data show that circulating neutrophils in COVID-19 exhibit an activated phenotype with enhanced NETosis and oxidative burst.

Purpose Sepsis remains amongst the most common causes of death worldwide. It has been described as a disease of the elderly, but contemporary data on risk factors and mortality is lacking. Materials and methods Multi-center longitudinal cohort study using non-public, state of California data from January 1, 2008 to September 31, 2015. Patients with sepsis, severe sepsis, and septic shock were identified using ICD-9-CM diagnosis and procedure codes with age subgroups of 18–44, 45–64, 65–74, 75–84, and >85 years old. Descriptive statistics and a single direct logistic regression model were used to present data on incidence and mortality and to identify independent factors associated with mortality. Results Of 30,282,159 total inpatient encounters, 20,358,569 met inclusion criteria and 1,566,306 met sepsis criteria. Conditions associated with mortality included metastatic cancer, age, liver disease, residing in a care facility, and a gastrointestinal source of infection as well as fungal infection. Mortality in the >85-year-old subgroup with septic shock was 45.7%, lower than previously reported. Conclusion Age remains an important sepsis risk factor, but other conditions correlated more closely with sepsis-associated death. Patients over 85 years of age suffering from septic shock may have a better chance of survival than previously thought.

Postoperative pulmonary complications contribute to perioperative morbidity and mortality in addition to being associated with increased health care costs. In this review article, we outline risk factors for the development postoperative pulmonary complications, describe their impact on perioperative outcomes, and focus on the role of intraoperative ventilation strategies in decreasing postoperative pulmonary complications.

Many industrial pharmaceutical manufacturing processes are composed of multiple-step batch operations. However, uncontrolled variations often occur during operations that affect the cell growth per...

OBJECTIVES A recently published simulation study suggested that women are inferior leaders of cardiopulmonary resuscitation efforts. The aim of this study was to compare female and male code leaders in regard to cardiopulmonary resuscitation outcomes in a real-world clinical setting. DESIGN Retrospective cohort review. SETTING Two academic, urban hospitals in San Diego, California. SUBJECTS One-thousand eighty-two adult inpatients who suffered cardiac arrest and underwent cardiopulmonary resuscitation. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS We analyzed whether physician code leader gender was independently associated with sustained return of spontaneous circulation and survival to discharge and with markers of quality cardiopulmonary resuscitation. Of all arrests, 327 (30.1%) were run by female physician code leaders with 251 (76.8%) obtaining return of spontaneous circulation, and 122 (37.3%) surviving to discharge. Male physicians ran 757 codes obtaining return of spontaneous circulation in 543 (71.7%) with 226 (29.9%) surviving to discharge. When adjusting for variables, female physician code leader gender was independently associated with a higher likelihood of return of spontaneous circulation (odds ratio, 1.36; 95% CI, 1.01-1.85; p = 0.049) and survival to discharge (odds ratio, 1.53; 95% CI, 1.15-2.02; p < 0.01). Additionally, the odds ratio for survival to discharge was 1.62 (95% CI, 1.13-2.34; p < 0.01) for female physicians with a female code nurse when compared with male physician code leaders paired with a female code nurse. Gender of code leader was not associated with cardiopulmonary resuscitation quality. CONCLUSIONS In contrast to data derived from a simulated setting with medical students, real life female physician leadership of cardiopulmonary resuscitation is not associated with inferior outcomes. Appropriately, trained physicians can lead high-quality cardiopulmonary resuscitation irrespective of gender.

Supplemental Digital Content is available in the text., Objectives: Due to a shortage of perfusionists and increasing utilization of extracorporeal membrane oxygenation in the United States, many programs are training nurses as bedside extracorporeal membrane oxygenation specialists (i.e., nurse-run extracorporeal membrane oxygenation). Our objective was to evaluate if a nurse-run extracorporeal membrane oxygenation program has noninferior survival to discharge and complication rates compared with a perfusionist-run extracorporeal membrane oxygenation program. Additionally, to sought to describe increases in extracorporeal membrane oxygenation capacity and the potential for cost savings by implementing a nurse-run extracorporeal membrane oxygenation program.

Introduction. The pathophysiology of infection with SARS-CoV-2 involves the lower airways and host-launched aggressive inflammatory responses leading to exacerbated lung damage in these vital tissues. Early clinical studies found that COVID-19 patients have higher levels of neutrophils in the circulation. Neutrophils are the most abundant leukocyte in circulation and are known to be highly proinflammatory due to production of neutrophil extracellular traps (NETosis). NETs are web-like chromatin structures coated with histones and proteases that both capture and kill invading pathogens. However, while being an effective countermeasure towards foreign microbes, this process also causes undesirable damage in host tissues. Therefore, we sought to characterize NETosis in circulating neutrophils from COVID-19 patients to determine whether this immunological response might be exacerbating or driving the disease state in COVID-19, rather than mitigating the virus. Methods.Blood was drawn daily from critically ill COVID-19 patients (n=16) after consent was obtained. Healthy controls (n=13) were screened for COVID-19 and gave blood once a week. Blood was drawn into lithium heparin tubes (BD Vacutainer). Neutrophils were isolated using PolymorphprepTM(PROGEN) per manufacturer's instructions. Cells were resuspended at 2x106 cells/ml for functional assays. Neutrophils were stimulated with increasing concentrations of PMA (Phorbol 12-myristate 13-acetate) of 2.5nM, 25nM and 250nM to stimulate NETosis via the canonical pathway, and nigericin at 15uM for the non-canonical pathway. NETosis was quantified using the Quant-iT™ PicoGreen™ dsDNA Assay Kit (Invitrogen) and by NET visualization via myeloperoxidase and nuclear staining (using Polyclonal Rabbit Anti-Human Myeloperoxidase by Dako and Hoescht stain by Invitrogen). Results.Functional NETosis assays of circulating neutrophils from COVID-19 patients demonstrate overall increased NETosis determined by increased release of dsDNA. This enhanced NETosis occurred at baseline and after stimulation with PMA when compared to healthy controls (Figure 1A, p

Background: Neutrophils are key players in the immune and aid in the defense against microorganisms. Neutrophil extracellular traps (NETs) are extracellular DNA complexes, which are released during NETosis, a programmed form of cell death. Although NETs are crucial in the fight against infectious agents, an overabundance of neutrophils has been implicated in many inflammatory lung conditions. Our aim is to determine whether an overabundance of NETosis is associated with clinical deterioration of patients with COVID-19. Methods: Circulating polymorphonuclear cells (neutrophils) were isolated from human peripheral blood of 20 human subjects with COVID-19. Neutrophils were seeded in 96-well plates and treated with 0, 2.5 nM, 25 nM, and 250 nM of phorbol 12-myrisate 13-acetate (PMA) or 12 uM nigericin for 2 hours to stimulate NET production via canonical and noncanonical pathways, respectively. Following incubation, wells were treated with micrococcal nuclease, supernatants were collected from each well, and extracellular DNA content to quantify NETosis was detected by fluorescent plate reader. We calculated acute physiology and chronic health evaluation (APACHE-II) scores for every human subject. These were calculated at the same time point at which the neutrophils were collected. They were then compared to the degree of NETosis and absolute neutrophil count (ANC). These were analyzed using a simple linear regression model. We also categorized participants based on APACHE-II scores (APACHE-II 15) and compared them to rates of NETosis using a bar graph. Results: APACHE II is a widely used ICU mortality prediction score that is used to risk-stratify patients. We found that participants with higher APACHE-II scores had higher rates of NETosis, both at 0 nM PMA and when stimulated with nigericin (figure 1a-b). This suggests that higher rates of NETosis correlate with increased disease severity. Additionally, we found a positive correlation between ANC and NETosis (Figure 1c-1d), suggesting that ANC itself is a reliable marker of NETosis and disease severity. Conclusion: NETosis is an important player in immune system defense but has also been implicated in various inflammatory lung conditions. We found that in patients with COVID-19, there was a positive correlation between worsening disease state, measure by APACHE II scores, and increased NETosis. This suggests that over-activation of neutrophils may play a role in disease progression. We also found a positive correlation between NETosis and ANC, indicating that the degree of circulating neutrophils is a reliable marker of the functional state of neutrophils, as well as disease severity.

Rationale: The ideal ventilator settings in patients with severe acute respiratory distress syndrome (ARDS) while on Extracorporeal Membrane Oxygenation (ECMO) are unknown. ELSO recommends modest driving pressures and PEEP (i.e., “lung rest”) during ECMO to minimize ventilator induced lung injury (VILI) and improve mortality. However, even lower driving pressures (DP) may improve inflammatory and lung injury biomarker profiles, and possibly improve mortality. The focus of this study was to evaluate the feasibility and impact of very-low DP in patients with ARDS on ECMO. Methods: Patients on ECMO due to ARDS from coronavirus disease 2019 had their DP decreased from 10 to 1-5 cmH2O for two hours, as tolerated. The other ventilator settings were unchanged and were consistent with ELSO guidelines;positive end-expiratory pressure (10-15 cmH2O) and a respiratory rate 10 breaths per minute. During the low DP protocol, the transpulmonary pressure was monitored with esophageal manometry. Plasma (for IL6 and sRAGE) and urine were collected before and after the protocol. Results: Thirty patients were enrolled and ultimately 21 patients underwent the low DP protocol. Seventeen were male, aged 51 ± 9 years, median BMI of 31.7 kg/m2 (IQR 27.4-35.2), with a median SOFA score of 10 (IQR 8-12) at ICU admission. There were no complications during the low DP protocol (1-5 cm H2O). The protocol was performed a median of 16 (IQR 13.5-20) hours after ECMO initiation. Average ECMO days were 21 (IQR 12.5-41) with a survival to hospital discharge of 43% (9/21). Baseline average tidal volume (TV) was 3.4±2.6 ml/kg of predicted body weight (PBW), during the low DP protocol the TV decreased to 2.7±3.2 ml/kg of PDW. Two groups were noted-those who had spontaneous breaths vs. those who did not (see Figure 1). Ten patients during the low DP protocol continued to have unchanged TV, 5.2±2.8 to 5.4±2.7 ml/kg of PBW due to spontaneous breathing found on esophageal manometry. Eleven patients had no spontaneous breaths and TV decreased from 1.76±0.57 to 0.2±0.38 ml/kg of PBW during the low DP protocol. The spontaneous vs. nonspontaneous breathing groups has a statistically different TV before, during, and after the low DP protocol (p

Guillain-Barré syndrome (GBS) is an ascending demyelinating polyneuropathy often associated with recent infection. Miller Fisher syndrome represents a variant with predominant facial and cranial nerve involvement, although Miller Fisher and Guillain-Barré overlap syndromes can occur. Guillain-Barré spectrum syndromes have been thought to be rare among solid organ transplant recipients. We describe an immunocompromised patient with a liver transplant who presented with ophthalmoplegia and bulbar deficits. His symptoms rapidly progressed to a state of descending paralysis involving the diaphragm; he then developed acute respiratory failure and eventually developed quadriparesis. Electromyography and a nerve conduction study demonstrated a severe sensorimotor axonal polyneuropathy consistent with Miller Fisher variant Guillain-Barré syndrome. Despite several negative nasopharyngeal swabs for COVID-19 polymerase chain reaction, a serology for SARS-CoV-2 IgG was positive. He was diagnosed with Miller Fisher-Guillain-Barré overlap syndrome with rapid recovery following treatment with plasma exchange. Although Guillain-Barré is a rare complication in solid organ transplant recipients, this case highlights the importance of rapid diagnosis and treatment of neurologic complications in transplant patients. Furthermore, it demonstrates a possible case of neurological complications from COVID-19 infection.

BackgroundIncreased inflammation is a hallmark of COVID-19, with pulmonary and systemic inflammation identified in multiple cohorts of patients. Definitive cellular and molecular pathways driving severe forms of this disease remain uncertain. Neutrophils, the most numerous leukocytes in blood circulation, can contribute to immunopathology in infections, inflammatory diseases and acute respiratory distress syndrome (ARDS), a primary cause of morbidity and mortality in COVID-19. Changes in multiple neutrophil functions and circulating cytokine levels over time during COVID-19 may help define disease severity and guide care and decision making.MethodsBlood was obtained serially from critically ill COVID-19 patients for 11 days. Neutrophil oxidative burst, neutrophil extracellular trap formation (NETosis), phagocytosis and cytokine levels were assessed ex vivo. Lung tissue was obtained immediately post-mortem for immunostaining.ResultsElevations in neutrophil-associated cytokines IL-8 and IL-6, and general inflammatory cytokines IP-10, GM-CSF, IL-1b, IL-10 and TNF, were identified in COVID-19 plasma both at the first measurement and at multiple timepoints across hospitalization (p < 0.0001). Neutrophils had exaggerated oxidative burst (p < 0.0001), NETosis (p < 0.0001) and phagocytosis (p < 0.0001) relative to controls. Increased NETosis correlated with both leukocytosis and neutrophilia. Neutrophils and NETs were identified within airways and alveoli in the lung parenchyma of 40% of SARS-CoV-2 infected lungs. While elevations in IL-8 and ANC correlated to COVID-19 disease severity, plasma IL-8 levels alone correlated with death.ConclusionsCirculating neutrophils in COVID-19 exhibit an activated phenotype with increased oxidative burst, NETosis and phagocytosis. Readily accessible and dynamic, plasma IL-8 and circulating neutrophil function may be potential COVID-19 disease biomarkers.

Author(s): Meier, Angela; Sell, Rebecca E; Malhotra, Atul | Abstract: Measuring driving pressure (defined by plateau pressure minus positive end-expiratory pressure) is a useful addition to existing variables when setting mechanical ventilation, particularly in the acute respiratory distress syndrome.

Background: Increased inflammation is a hallmark of COVID-19, with pulmonary and systemic inflammation identified in multiple cohorts of patients. Definitive cellular and molecular pathways driving severe forms of this disease remain uncertain. Neutrophils, the most numerous leukocytes in blood circulation, can contribute to immunopathology in infections, inflammatory diseases and acute respiratory distress syndrome (ARDS), a primary cause of morbidity and mortality in COVID-19. Neutrophilia, elevated neutrophil:lymphocyte ratios, and elevated neutrophil-associated cytokines are present in COVID-19, but changes in neutrophil functions have not been characterized. Here we analyzed the functional state of circulating neutrophils in COVID-19. Methods: Blood was obtained from critically ill COVID-19 patients over two weeks and healthy controls across multiple timepoints. Plasma cytokine profiles were assessed by bead array. Neutrophils were isolated and tested ex vivo for oxidative burst, neutrophil extracellular trap formation (NETosis) and phagocytosis. Lung tissue was obtained immediately post-mortem from COVID-19 patients for immunostaining. Results: Elevations in neutrophil-associated cytokines IL-8 and IL-6 were identified in COVID-19 plasma both at the first measurement and across their hospitalization (p < 0.0001). Elevations in cytokines IP-10, GM-CSF, IL-1b, IL-10 and TNF were also present at the first measurement and across hospital stays. Functionally, circulating neutrophils from COVID-19 patients had exaggerated oxidative burst (p < 0.0001), NETosis (p < 0.0001) and phagocytosis (p < 0.0001) relative to controls. Increased NETosis was found to be correlated with both leukocytosis and neutrophilia in COVID-19 patients. Neutrophils and NETs were identified within airways and alveoli in lung parenchyma. While elevations in IL-8 and ANC correlated to COVID-19 disease severity, plasma IL-8 levels alone correlated with death. Conclusions: Circulating neutrophils in COVID-19 exhibit an activated phenotype with increased oxidative burst, NETosis and phagocytosis. Readily accessible and dynamic, plasma IL-8 and circulating neutrophil function can be explored as potential COVID-19 disease biomarkers. Funding Statement: This work was supported by the Department of Veterans Affairs (salary support and VA Merit Award, PI Crotty Alexander) and NIH NHLBI (PI Crotty Alexander). Declaration of Interests: The authors report no conflicts of interest. Ethics Approval Statement: The research protocol was approved by the UCSD, VASDHS and Rady Children’s Hospital institutional review boards (IRBs) and all participants or designated family member gave written informed consent.

Bisphenol A (BPA) is a synthetic, organic compound frequently present in consumer plastics, including plastic-lined cans, water bottles, toys, and teeth sutures. Previous studies have shown that BPA can produce adverse health effects that include defects in reproductive function and altered prenatal/childhood development. However, little is known regarding the effects of BPA on immune function. In this study, we assessed the effect of BPA on human neutrophils, a critical component of the innate immune system’s defense against pathogens. We found that BPA induces a concentration-dependent increase in reactive oxygen species (ROS) generation by neutrophils, which is inhibited by the estrogen receptor-β antagonist PHTPP. Furthermore, incubation with the membrane-permeable calcium chelator BAPTA-AM and/or removal of extracellular calcium inhibited BPA-induced ROS production, indicating that the process is calcium dependent. Transwell chemotaxis assays revealed that BPA exposure reduces the chemotactic capacity of neutrophils in a gradient of the bacterial cell wall component f-Met-Leu-Phe, a potent chemoattractant. Exposure to BPA also inhibits the ability of neutrophils to kill methicillin-resistant Staphylococcus aureus, a leading human pathogen. Our findings reveal that BPA alters the in vitro function of neutrophils, including ROS production, chemotaxis, and bacterial killing, and raises the possibility of altered innate immunity in vivo, especially in those with compromised immune function and who can be exposed to BPA in a wide variety of products.

To assess incremental charges of patients experiencing venous thromboembolisms (VTE) across various types of elective inpatient surgical procedures with administration of general anesthesia in the US.The authors performed a retrospective study utilizing data from a nationwide hospital operational records database from July 2014 through June 2015 to compare a group of inpatients experiencing a VTE event post-operatively to a propensity score matched group of inpatients who did not experience a VTE. Patients included in the analysis had a hospital admission for an elective inpatient surgical procedure with the use of general anesthesia. Procedures of the heart, brain, lungs, and obstetrical procedures were excluded, as these procedures often require a scheduled ICU stay post-operatively. Outcomes examined included VTE events during hospitalization, length of stay, unscheduled ICU transfers, number of days spent in the ICU if transferred, 3- and 30-day re-admissions, and total hospital charges incurred.The study included 17,727 patients undergoing elective inpatient surgical procedures. Of these, 36 patients who experienced a VTE event were matched to 108 patients who did not. VTE events occurred in 0.2% of the study population, with most events occurring for patients undergoing total knee replacement. VTE patients had a mean total hospital charge of $60,814 vs $48,325 for non-VTE patients, resulting in a mean incremental charge of $11,979 (p .05). Compared to non-VTE patients, VTE patients had longer length of stay (5.9 days vs 3.7 days, p .001), experienced a higher rate of 3-day re-admissions (3 vs 0 patients) and 30-day re-admissions (7 vs 2 patients).Patients undergoing elective inpatient surgical procedures with general anesthesia who had a VTE event during their primary hospitalization had a significantly longer length of stay and significantly higher total hospital charges than comparable patients without a VTE event.

The extent of afucosylation, which refers to the absence of core fucose on Fc glycans, can correlate positively with the antibody-dependent cellular cytotoxicity (ADCC) activity of a monoclonal antibody (mAb). Therefore, it is important to maintain consistent afucosylation during cell culture process scale-up in bioreactors for a mAb with ADCC activity. However, there is currently a lack of understanding about the impact of partial pressure of carbon dioxide (pCO2 )-a parameter that can vary with bioreactor scale-on afucosylation. Using a small-scale (3 L) bioreactor model that can modulate pCO 2 levels through modified configurations and gassing strategies, we identified three cell culture process parameters that influence afucosylation of a mAb produced by a recombinant Chinese Hamster Ovary (CHO) cell line: pCO 2 , media hold duration (at 37°C), and manganese. These three-independent parameters demonstrated a synergistic effect on mAb afucosylation; increase in pCO 2 , media hold duration, and manganese consistently increased afucosylation. Our investigations into the underlying mechanisms through proteomic analysis indicated that the synergistic interactions downregulated pathways related to guanosine diphosphate-fucose synthesis and fucosylation, and upregulated manganese transport into the CHO cells. These new findings highlight the importance of considering potential differences in culture environment and operations across bioreactor scales, and understanding the impact of their interactions on product quality.

E-cigarettes are portrayed as safer relative to conventional tobacco. However, burgeoning evidence suggests that E-cigarettes may adversely affect host defenses. However, the precise mechanisms by which E-cigarette vapor alters innate immune cell function have not been fully elucidated. We determined the effects of E-cigarette exposure on the function and responses to infectious challenge of the most abundant innate immune cell, the neutrophil, using isolated human neutrophils and a mouse model of gram-negative infection. Our results revealed that human neutrophils exposed to E-cigarette vapor had 4.2-fold reductions in chemotaxis toward the bacterial cell-well component f-Met-Leu-Phe ( P < 0.001). F-actin polarization and membrane fluidity were also adversely affected by E-cigarette vapor exposure. E-cigarette-exposed human neutrophils exhibited a 48% reduction in production of reactive oxygen species (ROS; P < 0.001). Given the central role of ROS in neutrophil extracellular trap (NET) production, NET production was quantified, and E-cigarette vapor exposure was found to reduce NETosis by 3.5-fold ( P < 0.01); formulations with and without nicotine containing propylene glycol exhibiting significant suppressive effects. However, noncanonical NETosis was unaffected. In addition, exposure to E-cigarette vapor lowered the rate of phagocytosis of bacterial bioparticles by 47% ( P < 0.05). In our physiological mouse model of chronic E-cigarette exposure and sepsis, E-cigarette vapor inhalation led to reduced neutrophil migration in infected spaces and a higher burden of Pseudomonas. These findings provide evidence that E-cigarette use adversely impacts the innate immune system and may place E-cigarette users at higher risk for dysregulated inflammatory responses and invasive bacterial infections.

Anesthetics are widely used drugs administered in a multitude of clinical settings. Their impacts on various functions of the immune system have been studied but are still not fully understood. Neutrophil granulocytes are a critical first-line host defense mechanism against infections and contribute to the inflammatory phase of wound healing, but dysregulated neutrophil activation can also precipitate perioperative organ injury. A better understanding of the interactions between common anesthetics and neutrophils may reveal considerations toward optimizing treatment of our most vulnerable patients in the intensive care unit and in the perioperative setting.

Peripartum cardiomyopathy is a rare form of acute heart failure but the major cause of all deaths in pregnant patients with heart failure. Improved survival rates in recent years, however, emphasize the importance of early recognition and initiation of heart failure treatment. This article, therefore, attempts to raise awareness among cardiac and obstetric anesthesiologists as well as intensivists of this often fatal diagnosis. This review summarizes theories of the pathophysiology and outcome of peripartum cardiomyopathy. Based on the most recent literature, it further outlines diagnostic criteria and treatment options including medical management, mechanical circulatory support devices, and heart transplantation. Earlier recognition of this rare condition and a new generation of mechanical circulatory devices has contributed to the improved outcome. More frequently, patients in cardiogenic shock who fail medical management are successfully bridged to recovery on extracorporeal circulatory devices or survive with a long-lasting implantable ventricular assist device. The outcome of transplanted patients with peripartum cardiomyopathy, however, is worse compared to other recipients of heart transplants and warrants further investigation in the future.

Myxedema coma is a rare but highly fatal condition with reported mortality >40%-50%. Early recognition and prompt treatment are critical for survival. Here we describe a case of possible postoperative myxedema coma after subacute neck hematoma evacuation after hemithyroidectomy in a patient on concurrent amiodarone therapy. Symptoms included somnolence, hypothermia, and prolonged QTc with torsades de pointes resistant to magnesium therapy requiring defibrillation and overdrive pacing. Consideration of the possible diagnosis of myxedema coma resulted in prompt therapy and symptom resolution within 48 hours. Thyroid disorders, although rare, should be considered in the postoperative setting.

The impact of volatile anesthetics on cancer progression has been observed for decades, but sex differences have not been described. Male and female immune systems vary considerably, and the immune system plays an important role in limiting cancer growth. Currently, mouse models describing the impact of volatile anesthetics on cancer growth are limited to same-sex models. In this brief report, we describe a sex-specific impact of isoflurane on melanoma growth observed in wild-type but not in immune-deficient mice. Future experimental designs related to anesthesia and cancer should evaluate the biological variable of sex in a systematic manner.

Ventilator associated pneumonia (VAP) is a complication of mechanically assisted ventilation, and the ideal initial treatment strategy is unclear. Heyland et al. explore monotherapy versus combination therapy for the initial treatment of suspected VAP, in a randomized trial of ICU patients with suspected VAP who received either Meropenem in combination with Ciprofloxacin or Meropenem alone. There was no mortality difference between treatment groups, and the duration of intensive care unit and hospitals stays was similar. There was no difference between the clinical and microbiological treatment response or the emergence of antibiotic-resistant bacteria. The adequacy of initial antibiotics was higher in the combination therapy group only in a subgroup of patients infected with difficult-to-treat gram-negative bacteria, but clinical outcomes still did not differ. The authors concluded that, for critically ill patients with suspected VAP, monotherapy is an adequate treatment regimen except for patients at high risk for difficult to treat gram-negative bacteria.

Typical manufacturing bio-processes operate as multi-step batch operations. Abnormal variations are often experienced in commercial manufacturing which affects the ability to maintain the product supply to the patients. The low titer is usually highly correlated with high lactate in recombinant Chinese hamster ovary (CHO) cells producing immunoglobulin G, but there are limited means to analyze the vast amount of process data archived from manufacturing sites and understand the causes of the multiple sources of process variability. In this study, we investigate diverse data from a cell culture process, from historical runs of a multi-step manufacturing process for a recombinant antibody. Data includes intra-batch measurements, batch conditions and media preparation measurements. Cell culture process stages from inoculum train to production runs. To analyze manufacturing variability in multiple stages with various sources of data sets, we first adopt principal component analysis (PCA) based monitoring to find in which space high lactate and low lactate batches can be separated, and apply clustering to identify fault directions for intra-batch data from production runs. We then predict final lactate using data from inoculum stages with a nonlinear support vector machine (SVM) classifier. These models are used to uncover potential causes of high lactate. This data-driven modelling can provide new insights on process characteristics to understand the sources of process variability and thus mitigation procedures can be implemented.

Continuous-flow left ventricular assist devices (LVADs) are increasingly implanted to support patients with end-stage heart failure. These patients are at high risk for complications, many of which necessitate emergency care. While rehospitalization rates have been described, there is little data regarding emergency department (ED) visits. We hypothesize that ED visits are frequent and often require admission after LVAD implantation. We performed a retrospective review of patients in our health-care system followed by the advanced heart failure service for LVAD management after implantation between January 2011 and July 2015. We accounted for all ED visits in our system through February 2016, 7 months after the last implantation included. Clinically relevant demographic variables and ED visit details were recorded and analyzed to describe this population. We identified 81 patients with complete data, among whom there were 283 visits (3.49 visits/patient), occurring at a rate of approximately 7.3 ED visits per patient per year alive with LVAD. The most common reason for an ED visit is a complication related to bleeding (18% of visits), followed by chest pain (14%) and dizziness or syncope (13%). Thirty-six percent of patients were discharged from the ED without hospital admission. A growing populace with implanted LVADs represents an important population within emergency medicine. They are at risk for significant complications and frequently present to the ED. While many of these visits may be managed without hospital admission, this specialized patient group represents a potential area for improvement in provider education.

Objective Medical errors play a large role in preventable harms within our health care system. Medications administered in the ICU can be numerous, complex and subject to daily changes. We describe a method to identify medication errors with the potential to improve patient safety. Design A quality improvement intervention featuring a daily medication time out for each patient was performed during rounds. Setting A 12-bed Cardiac Surgical ICU at a single academic institution with approximately 180 beds. Intervention After each patient encounter, the current medication list for the patient was read aloud from the electronic medical record, and the team would determine if any were erroneous or missing. Medication changes were recorded and graded post-hoc according to perceived significance. Results This intervention resulted in 285 medication changes in 347 patient encounters. 179 of the 347 encounters (51.6%) resulted in at least one change. Of the changes observed, 40.4% were categorized as trivial, 50.5% as minor and 9.1% were considered to have significant potential impact on patient care. The average time spent per patient for this intervention was 1.24 (SD 0.65) minutes. Conclusions A daily medication time out should be considered as an additional mechanism for patient safety in the ICU.

Large-scale fed-batch cell culture processes of CHO cells are the standard platform for the clinical and commercial production of monoclonal antibodies. Lactate is one of the major by-products of CHO fed-batch culture. In pH-controlled bioreactors, accumulation of high levels of lactate is accompanied by high osmolality due to the addition of base to control pH of the cell culture medium, potentially leading to lower cell growth and lower therapeutic protein production during manufacturing. Lactate dehydrogenase (LDH) is an enzyme that catalyzes the conversion of the substrate, pyruvate, into lactate and many factors including pyruvate concentration modulate LDH activity. Alternately, pyruvate can be converted to acetyl-CoA by pyruvate dehydrogenases (PDHs), to be metabolized in the TCA cycle. PDH activity is inhibited when phosphorylated by pyruvate dehydrogenase kinases (PDHKs). In this study, we knocked down the gene expression of lactate dehydrogenase A (LDHa) and PDHKs to investigate the effect on lactate metabolism and protein production. We found that LDHa and PDHKs can be successfully downregulated simultaneously using a single targeting vector carrying small inhibitory RNAs (siRNA) for LDHa and PDHKs. Moreover, our fed-batch shake flask evaluation data using siRNA-mediated LDHa/PDHKs knockdown clones showed that downregulating LDHa and PDHKs in CHO cells expressing a therapeutic monoclonal antibody reduced lactate production, increased specific productivity and volumetric antibody production by approximately 90%, 75% and 68%, respectively, without appreciable impact on cell growth. Similar trends of lower lactate level and higher antibody productivity on average in siRNA clones were also observed from evaluations performed in bioreactors.

Blood samples from multiple sites are collected in multicenter trials, and frequently shipped to centralized laboratories for processing and comparable experimental evaluation. It is therefore of crucial interest to assess the preservation of immune cell functions after overnight shipment of whole blood. Here we evaluated the ability of pDCs, mDCs and monocytes to respond to TLR ligands at multiple timepoints following venipuncture as compared to immediate processing. Our results demonstrate a profound impairment of APC function, in particular of IFN-α production of pDCs, if whole blood was processed later than 6 h after venipuncture. Overnight shipment or extended rest of whole blood before processing therefore severely compromises the ability of APCs to respond to TLR ligands, and this has to be taken into consideration when designing multicenter trials.

Virus-specific CD8 + T cells play a central role in the control of viral infections, including human immunodeficiency virus type 1 (HIV-1) infection. However, despite the presence of strong and broad HIV-specific CD8 + T-cell responses in chronic HIV-1 infection, these cells progressively lose critical effector functions and fail to clear the infection. Mounting evidence suggests that the upregulation of several inhibitory regulatory receptors on the surface of CD8 + T cells during HIV-1 infection may contribute directly to the impairment of T-cell function. Here, we investigated the role of killer immunoglobulin receptors (KIR), which are expressed on NK cells and on CD8 + T cells, in regulating CD8 + T-cell function in HIV-1 infection. KIR expression was progressively upregulated on CD8 + T cells during HIV-1 infection and correlated with the level of viral replication. Expression of KIR was associated with a profound inhibition of cytokine secretion, degranulation, proliferation, and activation by CD8 + T cells following stimulation with T-cell receptor (TCR)-dependent stimuli. In contrast, KIR + CD8 + T cells responded potently to TCR-independent stimulation, demonstrating that these cells are functionally competent. KIR-associated suppression of CD8 + T-cell function was independent of ligand engagement, suggesting that these regulatory receptors may constitutively repress TCR activation. This ligand-independent repression of TCR activation of KIR + CD8 + T cells may represent a significant barrier to therapeutic interventions aimed at improving the quality of the HIV-specific CD8 + T-cell response in infected individuals.

T helper (Th) 17 cells are a distinct lineage of CD4+ T cells mediating tissue inflammation through the secretion of IL-17. In addition, it has been shown that the expression of the transcriptional factor RORgammat is responsible for the induction and maintenance of this cell line. Th17 cells are believed to be involved in a variety of autoimmune disorders, but may also play an important role in host defense. Here we describe a novel technique to reproducibly isolate viable Th17 cells based on their IL-17 secreting ability. We confirmed Th17 cell enrichment by quantitative PCR analysis and demonstrate that positively selected cells using this technique express significantly increased mRNA levels of RORgammat, IL-23 receptor and CCR4 when compared to negatively selected cells. Furthermore, we show that purified Th17 cells can be maintained in long-term culture and expand in vitro. In conclusion, this technique will allow for the first time the direct, ex vivo analysis of phenotypic and functional properties of Th17 cells.

Increased PD-L1 expression has been reported in HIV-1-infected individuals, but the mechanisms leading to PD-L1 upregulation remain to be elucidated. Here we demonstrate that HIV-1-derived Toll-like receptor (TLR)7/8 ligands can induce MyD88-dependent upregulation of PD-L1 on plasmacytoid dendritic cells, myeloidic dendritic cells and monocytes. These data suggest a mechanism through which HIV-1-derived TLR ligands might contribute to the functional impairment of virus-specific PD-1-positive T cells by inducing the upregulation of PD-L1 on antigen-presenting cells.