In Situ Simulation as a Quality Improvement Tool to Identify and Mitigate Latent Safety Threats for Emergency Department SARS-CoV-2 Airway Management: A Multi-Institutional Initiative

BACKGROUND

In situ simulation has emerged as a powerful quality improvement (QI) tool in the identification of latent safety threats (LSTs). Following the first wave of SARS-CoV-2 at an urban epicenter of the disease, a multi-institutional collaborative was formed to integrate an in situ simulation protocol across five emergency departments (EDs) for systems improvement of acute airway management.

METHODS

A prospective, multi-institutional QI initiative using two Plan-Do-Study-Act (PDSA) cycles was implemented across five EDs. Each institution conducted simulations involving mannequins in acute respiratory failure requiring definitive airways. Simulations and systems-based debriefs were standardized. LSTs were collected in an online database, focused on (1) equipment availability, (2) infection control, and (3) communication.

RESULTS

From June 2020 through May 2021, 58 of 70 (82.9%) planned simulations were completed across five sites with 328 unique individual participants. Overall LSTs per simulation (7.00-4.69, p < 0.001) and equipment LSTs (3.00-1.46, p < 0.001) decreased from cycle 1 to cycle 2. Changes in mean LSTs for infection control and communication categories varied among sites. There was no correlation between total LSTs or any of the categories and team size. Number of beds occupied was significantly negatively correlated with total and infection control LSTs.

CONCLUSION

This study was unique in simultaneously running a structured in situ protocol across numerous diverse institutions during a global pandemic. This initiative found similar categories of threats across sites, and the protocol developed empowered participants to implement changes to mitigate identified threats.

Self-reported gastrointestinal disorders among veterans with gulf war illness with and without posttraumatic stress disorder

BACKGROUND

Gulf War Illness (GWI) is a chronic, multi-symptom disorder affecting 25%-32% of Gulf War veterans. Veterans with GWI disproportionately suffer from gastrointestinal (GI) disorders. Given the increasing evidence supporting a gut-brain axis, we explore the relationship between post-traumatic stress disorder (PTSD), GWI, and self-reported GI disorders among GW veterans.

METHODS

Veterans from the Gulf War Era Cohort and Biorepository responded to a mail-based survey (N = 1058). They were stratified by GWI (Centers for Disease Control definition) and PTSD status. This yielded three groups: GWI-, GWI+/PTSD-, and GWI+/PTSD+. Multivariable logistic regression adjusting for demographic and military characteristics examined associations between GWI/PTSD groups and GI disorders. Results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI).

KEY RESULTS

The most frequently reported GI disorders were irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and colon polyps (CP). The GWI+/PTSD+ group had a higher odds of these disorders than the GWI+/PTSD- group (aOR_IBS  = 3.12, 95% CI: 1.93-5.05; aOR_GERD  = 2.04, 95% CI: 1.44-2.90; aOR_CP  = 1.85, 95% CI: 1.23-2.80), which had a higher odds of these disorders than the GWI- group (aOR_IBS  = 4.38, 95% CI: 1.55-12.36; aOR_GERD  = 2.51 95% CI: 1.63-3.87; aOR_CP  = 2.57, 95% CI: 1.53-4.32).

CONCLUSIONS & INFERENCES

GW veterans with GWI and PTSD have significantly higher odds of specific self-reported GI disorders than the other groups. Given the known bidirectional influences of the gut and brain, these veterans may benefit from a holistic healthcare approach that considers biopsychosocial contributors to the assessment and management of disease.

In Situ Simulation as a Tool to Longitudinally Identify and Track Latent Safety Threats in a Structured Quality Improvement Initiative for SARS-CoV-2 Airway Management: A Single-Center Study

BACKGROUND

In situ simulation has emerged as a powerful tool for identifying latent safety threats (LSTs). After the first wave of the SARS-CoV-2 pandemic, an urban community emergency department (ED) identified opportunities for improvement surrounding acute airway management and particularly focused on infection control precautions, equipment availability, and interprofessional communication during acute resuscitation. Using the Model for Improvement, a hybrid in situ/quality improvement initiative was implemented using Plan-Do-Study-Act (PDSA) cycles to enhance systems for intubating patients with SARS-CoV-2.

METHODS

Three PDSA cycles consisting of 10 simulations each were conducted from June 2020 through February 2021. Latent safety threats (LST) were identified through an in situ simulation scenario involving a patient with SARS-CoV-2 in acute respiratory failure. LSTs were collected through structured debriefs focused on (1) infection control, (2) equipment availability, and (3) communication. The SAFER-Matrix was used to score LSTs according to frequency and likelihood of harm by members of the ED QI team (SAFER score). The research team worked with the same QI leaders to implement action plans based on scored threats using cause-and-effect and driver diagrams. The Donabedian model was used to conceptually evaluate the quality of interventions upon conclusion of the third PDSA cycle.

RESULTS

The median SAFER score decreased from 10.94 in PDSA cycle 1 to 6.77 in PDSA cycle 2 to 4.71 in PDSA cycle 3. Across all identified LSTs, the SAFER score decreased by 3.114 for every additional PDSA cycle ( P = 0.0167). When evaluating for threats identified as being primarily structure based, there was a decrease in SAFER score of 1.28 per every additional PDSA cycle ( P = 0.001). There was a decrease in total count of LST of 0.20 per additional simulation run ( P = 0.02) after controlling for shift type, census, perceived workload, team size, and prior attendance in simulations across all PDSA cycles.

CONCLUSIONS

This study presents a blueprint for the utilization of in situ simulation through multiple waves of the SARS-CoV-2 pandemic to identify LSTs and use the SAFER score as a surrogate marker to monitor the impact of interventions for a safer environment for both medical staff and patients.

Safety Considerations for In Situ Simulation in Closed SARS-CoV-2 Units

SUMMARY STATEMENT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic placed a tremendous strain on the healthcare system, which led to the deployment of new personnel into acute care settings, early graduation of medical students, and development of new treatment spaces. Education teams at the Montefiore Health System and New York Health and Hospitals/Jacobi Medical Center found simulation, both laboratory-based and in situ, critical to the training of medical staff and investigation of latent safety threats. Through our experience, we encountered unique infection control concerns based on in situ sessions, which prompted us to redesign our programs for the treatment of SARS-CoV-2. Using this experience, we outline our rationale for the use of in situ simulation for newly developed SARS-CoV-2 spaces along with recommendations on safety checks to consider before starting.

Can the negative pressures found in obstructive sleep apnea and Eustachian tube dysfunction be related?

OBJECTIVE

The association between obstructive sleep apnea (OSA) and Eustachian tube dysfunction (ETD) is well known. When both exist in a single pediatric patient, one of the expected culprits is adenoid enlargement. We hypothesize, in contrast, that the negative pharyngeal pressure found in OSA may be transmitted to the middle ear as negative middle ear pressure (MEP), which subsequently results in pathology. The objective of this study was to determine whether the degree of OSA and MEP are associated while using MEP as a quantifiable measurement of ETD.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary academic center (Jan 2000-Jan 2018).

SUBJECTS AND METHODS

The relationship between apnea-hypopnea index (AHI) and MEP was examined. A non-anatomic model was utilized to support causality.

RESULTS

Thirty-four pediatric patients and twenty-three adult patients were included in the analysis. REM AHI showed a moderate negative correlation with MEP in children (r = -0.265), and a weak positive correlation with MEP in adults (r = 0.171). Children with an AHI in the severe OSA category had a more negative mean MEP than those in the mild category (p = 0.36). Adults with an AHI in the severe OSA category had a more positive mean MEP than those in the mild category (p = 0.11).

CONCLUSION

In children, increasing severity of OSA is associated with a negative MEP, suggesting that negative pressure associated with OSA may be transmitted to the middle ear. In adults, increasing severity of OSA is associated with a more positive MEP.

Use of Predictive Modeling to Tailor Molecular Testing Utilization for Thyroid Nodules

OBJECTIVE

Various risk stratification systems for cytologically indeterminate thyroid nodules are available. However, malignancy risk assessment data, such as ultrasound features, are not always used when the decision is to order molecular testing or not. Our aim was to investigate the utility of molecular testing after incorporating an algorithm with ultrasound-based risk of malignancy (ROM) estimation.

STUDY DESIGN

Diagnostic/prognostic study.

SETTING

Single-institution urban tertiary care center.

METHODS

We performed a single-institution retrospective chart review of all thyroid nodules that had undergone molecular testing. A web-based Malignancy Risk Estimation System for Thyroid Nodules was utilized with ultrasound findings to stratify malignancy risk according to the Korean Thyroid Imaging Reporting and Data System (TI-RADS), French TI-RADS, American Association of Clinical Endocrinology guideline, and American Thyroid Association guideline. A novel algorithm for utilizing molecular testing at our institution was developed with the Korean TI-RADS and with recommendations from the American Thyroid Association and National Comprehensive Cancer Network.

RESULTS

The Korean TI-RADS performed best in our population (area under the curve = 0.83). A positive molecular test result had a positive association with a higher ROM according to all 4 models (P < .05). Use of our algorithm prior to molecular testing would have prevented 38% of benign/low-ROM negative nodules (n = 28) from being tested.

CONCLUSION

In patients with indeterminate thyroid nodules, an algorithm built on pre- and posttest probability to guide molecular testing might reduce unnecessary testing of benign and low-risk nodules.

Implementation of an Online Multimedia Pediatric Tracheostomy Care Module for Healthcare Providers

OBJECTIVES/HYPOTHESIS

To investigate the effect of a multimedia educational module on provider attitudes toward pediatric tracheostomy care. We also describe the process of module development and dissemination at an academic children's hospital.

STUDY DESIGN

Prospective observational study.

METHODS

The pediatric airway committee at an urban tertiary care center developed a multimedia pediatric tracheostomy care module. Nurses, respiratory therapists, as well as resident, fellow, and attending physicians caring for pediatric patients with tracheostomies were eligible. Managers and clinical supervisors from various units recruited participants to complete the pediatric tracheostomy care electronic module and pre- and postassessment knowledge quizzes and surveys. Provider confidence was analyzed using Kruskal-Wallis H-test and Mann-Whitney U-test, and paired t-test was used to compare pre- and postmodule quiz scores.

RESULTS

A total of 422 participants completed the module. A total of 275 participants completed the premodule survey, 385 completed the premodule quiz, 253 completed the postmodule survey, and 233 completed the postmodule quiz. Participants included providers in the neonatal intensive care unit, pediatric intensive care unit, pediatric emergency department, and pediatric wards. Postmodule surveys demonstrated a significant reduction in the average percentage of participants indicating lack of confidence with regards to changing an established tracheostomy, responding to accidental decannulation of established tracheostomy, and responding to accidental decannulation of fresh tracheostomy (P < .001). Average quiz scores increased by 5.6 points from 83.0% to 88.6% (P < .00001).

CONCLUSIONS

A multimedia educational module can improve provider perception of their knowledge and confidence surrounding pediatric tracheostomy management.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1893-1901, 2021.

Structural insights into the ene-reductase synthesis of profens

Reduction of double bonds of α,β-unsaturated carboxylic acids and esters by ene-reductases remains challenging and it typically requires activation by a second electron-withdrawing moiety, such as a halide or second carboxylate group. We showed that profen precursors, 2-arylpropenoic acids and their esters, were efficiently reduced by Old Yellow Enzymes (OYEs). The XenA and GYE enzymes showed activity towards acids, while a wider range of enzymes were active towards the equivalent methyl esters. Comparative co-crystal structural analysis of profen-bound OYEs highlighted key interactions important in determining substrate binding in a catalytically active conformation. The general utility of ene reductases for the synthesis of (R)-profens was established and this work will now drive future mutagenesis studies to screen for the production of pharmaceutically-active (S)-profens.

CABG - Challenging Cases in Apollo Hospitals Dhaka, A Decade of Experience

Objective: To show outcome of challenging cases of Coronary Artery Bypass Graft (CABO)Methods: A retrospective study, done in Apollo Hospitals Dhaka from 02-05-2005 to 13.12.2014. Total 1892 CABO cases were reviewed- Emergency: 22 cases, Off-pump: 1257 cases, Arrested heart: 554 cases, On-pump beating heart: 81 cases, MIDCAB: 2 cases. Female - 213 (11.25%), male -1679 (88.74%). Associated co-morbities: peripheral vascular disease: 19 cases, COPD: 78 cases, on dialysis: 17 cases, ventricular septal ruptures :10 cases, carotid occlusive disease: 88 cases, old stroke: 58 cases, permanent pacemaker: 4 cases, preoperative ventilator: 29 cases, left ventricular aneurysm: 58 cases, severe mitral regurgitation: 5 cases, EF: 31-50% =260 cases, 21-30% =147 cases, 15- 20% = 8 cases. Associated procedures -left ventricular aneurysm repair: 42 cases, mitral valve replacement: 30 cases, aortic valve replacement: 25 cases ,double valve replacement: 3 cases, RA myxoma removal: 1 case, LV aneurysm repair with mitral valve procedure: 5 cases , LV aneurysm repair with ventricular septal rupture repair: 5 cases, ventricular septal rupture repair: 10 cases, aorto-femoral bypass: 3 cases, ileo femoral bypass: 1 case, left aorto-axillary bypass: 1 case , Bentall procedure with Brachio-cephalic artery re-implantation: 1 case, Aorto-bifemoral bipopliteal bypass: 1 case, redo CABO-7, IABP preoperatively: 12 cases.Results: Overall mortality rate 2.12% (39 cases), emergency 9.09 % (2 cases) mortality, routine mortality 1.97% (37 cases).Conclusion: Challenging cases of CABO can be done with acceptable morbidity and mortality with good long term outcome.Pulse Vol.9 January-December 2016 p.6-14

Effects of Citrus junos by-products fermented with multistrain probiotics on growth performance, immunity, caecal microbiology and meat oxidative stability in broilers

1. The present study was conducted to develop Citrus junos probiotics (CJP), using by-products of Citrus junos fermented with multispecies probiotic bacteria including Saccharomyces cerevisiae, Enterococcus faecium, Lactobacillus acidophilus and Bacillus subtilis. The effects of dietary CJP on the growth performance, immune status, caecal microbiology and meat oxidative stability of broiler were investigated. 2. A total of 240 one-day-old Ross broiler chicks were used in a 35-d experiment in which the chicks were randomly allotted to one of the 4 dietary treatments (0, 5, 10 and 20 g CJP/kg diet) in a completely randomised design. 3. Dietary supplementation of 5 g/kg CJP significantly increased body weight, average daily gain and average daily feed intake of broiler during the overall experimental period. 4. Serum immunoglobulin (Ig)M concentration was significantly increased by 10 and 20 g/kg CJP, whereas the IgG and IgA concentration remained unaffected. In addition, 20 g/kg CJP significantly inhibited proliferation of Escherichia coli without affecting the concentration of Lactobacillus or Bacillus spp. 5. A significant reduction in the thiobarbituric acid reactive substances values of breast and thigh meat was observed in response to increasing concentration of dietary CJP. 6. Thus, the results suggest that CJP up to a concentration of 20 g/kg can be used in the diet of broilers to improve immunity and to reduce caecal E. coli and TBARS values of breast and thigh meat without any adverse effects on growth performance.

Effect of Sea Tangle (Laminaria japonica) and Charcoal Supplementation as Alternatives to Antibiotics on Growth Performance and Meat Quality of Ducks

A total of 150 growing ducks were assigned to five dietary treatments to study the effect of sea tangle and charcoal (STC) supplementation on growth performance and meat characteristics in a completely randomized design. There were six replicates and five ducklings in each replication. The five dietary treatments were control, antibiotic, and 0.1%, 0.5%, and 1% STC supplemented diets. No significant differences were found on ADG, ADFI, and gain:feed among treatments in different weeks. The overall (0 to 3 weeks) ADFI decreased in antibiotic treatment (p<0.05) whereas the gain:feed increased significantly upon 1.0% STC supplementation compared to control (p<0.05). No significant variation was found in meat chemical composition except crude fat content which was high in 1.0% STC dietary group (p<0.05). Meat cholesterol was reduced in 0.1% STC group (p<0.05) compared to other dose levels while serum cholesterol was unaffected. High density lipoprotein (HDL) content was high in 1.0% STC (p<0.05) and low density lipoprotein (LDL) was low in 0.1% and 1.0% STC dietary groups (p = 0.06). No significant effect was found on the thiobarbituric acid reactive substances (TBARS) of fresh meat, whereas the TBARS value of meat preserved for 1 week was reduced significantly in STC dietary groups (p<0.05). The 0.1% STC dietary group showed an increased myristic acid (p = 0.07) content whereas, the content of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids increased in STC supplementation than antibiotic group (p<0.05). An increased concentration of omega-3 fatty acids and a reduced ratio of n-6/n-3 PUFA ratio was found upon 1.0% STC supplementation compared to antibiotic dietary group (p<0.05). Therefore, 1.0% STC dietary supplementation can be used as alternatives to antibiotics in duck production.

Effects of resveratrol and essential oils on growth performance, immunity, digestibility and fecal microbial shedding in challenged piglets

A study was conducted to evaluate the effects of resveratrol and essential oils from medicinal plants on the growth performance, immunity, digestibility, and fecal microbial shedding of weaned piglets. A total of 48 weaned piglets (8 kg initial weight, 28-d-old) were randomly allotted to four dietary treatments with 3 replications of 4 piglets each. The dietary treatments were NC (negative control; basal diet), PC (positive control; basal diet+0.002% apramycin), T1 (basal diet+0.2% resveratrol), and T2 (basal diet+0.0125% essential oil blend). All piglets were orally challenged with 5 ml culture fluid containing 2.3×10⁸ cfu/ml of Escherichia coli KCTC 2571 and 5.9×10⁸ cfu/ml Salmonella enterica serover Typhimurium. The PC group (p<0.05) showed the highest average daily gain (ADG) and average daily feed intake (ADFI) throughout the experimental period, although feed conversion ratio (FCR) was improved in the T1 group (p>0.05). Serum IgG level was increased in the T1 group, whereas TNF-α levels was reduced in the supplemented groups compared to control (p<0.05). The PC diet improved the dry matter (DM) digestibility, whereas PC and T2 diets improved nitrogen (N) digestibility compared to NC and T1 diets (p<0.05). Fecal Salmonella and E. coli counts were reduced in all treatment groups compared to control (p<0.05). Fecal Lactobacillus spp. count was increased in the T2 group compared to others (p<0.05). Dietary treatments had no significant effect on fecal Bacillus spp. count throughout the entire experimental period. Based on these results, resveratrol showed strong potential as antibiotic alternatives for reversing the adverse effects of weaning stress on growth performance, immunity and microbial environment in E. coli and Salmonella-challenged piglets.

Comparison of single and blend acidifiers as alternative to antibiotics on growth performance, fecal microflora, and humoral immunity in weaned piglets

The banning of the use of antibiotics as feed additive has accelerated investigations of alternative feed additives in animal production. This experiment investigated the effect of pure citric acid or acidifier blend supplementation as substitute for antibiotic growth promoters on growth performance, fecal microbial count, and humoral immunity in weaned piglets challenged with Salmonella enterica serover Typhimurium and Escherichia coli KCTC 2571. A total of 60 newly weaned piglets (crossbred, 28-d-old; average 8 kg initial weight) were randomly assigned to four dietary treatments in a completely randomized design. Dietary treatments included NC (negative control; basal diet), PC (positive control; basal diet+0.002% apramycin), T1 (basal diet+0.5% pure citric acid), and T2 (basal diet+0.4% acidifier blend). All piglets were orally challenged with 5 mL of culture fluid containing 2.3×10⁸ cfu/mL of E. coli KCTC 2571 and 5.9×10⁸ cfu/mL of S. typhimurium at the beginning of the experiment. The PC group showed the highest ADG and ADFI, whereas gain:feed was improved in the PC and T1 group (p<0.05). All dietary treatments showed significant reduction in fecal counts of Salmonella and E. coli, compared to NC (p<0.05), with PC being better than T1 and T2. Significant elevation in fecal Lactobacillus spp. counts was shown by treatments with T1, T2, and PC, whereas Bacillus spp. counts were increased by treatment with T1 and T2 compared to NC and PC diet (p<0.05). Serum IgG concentration was increased by T1 diet (p<0.05), whereas IgM and IgA were not significantly affected by any of the dietary treatments (p>0.05). From these above results, it can be concluded that, as alternatives to antibiotics dietary acidification with pure citric acid or acidifiers blend did not fully ameliorate the negative effects of microbial challenges in respect of growth performance and microbial environment, however improved immunity suggested further research with different dose levels.

Effects of fermented corni fructus and fermented kelp on growth performance, meat quality, and emission of ammonia and hydrogen sulphide from broiler chicken droppings

1. Corni fructus is the fruit of Cornus officinalis, a dogwood species. This study was conducted to prepare fermented corni fructus preparation (FCFP) and fermented kelp (FK) from corni fructus and by-products of Laminaria japonica fermented with Bacillus subtilis and Aspergillus oryzae. 2. The effects of dietary FCFP and FK as replacer of oxytetracycline (OTC) on growth performance, meat composition, meat oxidative stability, and emissions of ammonia (NH3) and hydrogen sulphide (H2S) from broiler chicken droppings were investigated. 3. A total of 140 d-old broiler chicks were randomly allotted to 4 dietary treatments including control, OTC (0.05 g/kg), FCFP (5 g/kg), and FK (5 g/kg). 4. Overall, inclusion of FCFP resulted in lower weight gain and feed intake during the overall experimental period. Broilers fed FCFP diets tended to have lower crude fat and higher crude ash content in the carcasses. 5. In the fresh state, the malondialdehyde (MDA) value of broiler meat was lower in the FK supplemented group. At one week, meat from broilers fed antibiotic and FK diets had lower MDA values, whereas at 2 weeks broiler meat from all dietary treatment groups had lower MDA values than the control. 6. Dietary supplementation with FK significantly reduced faecal NH3 emissions throughout the experimental period, whereas dietary OTC and FCFP supplementation increased NH3 emissions at 2 and 4 weeks. There were no significant effects of dietary treatments on H2S emissions throughout the experimental period, except during week one, when FCFP supplementation reduced the emission. 7. In conclusion, dietary supplementation with 5 g/kg FK improved the oxidative stability of broiler meat and reduce faecal NH3 emissions without affecting growth performance.

Immunological biomarkers: catalysts for translational advances in autoimmune diabetes

In a recent workshop organized by the JDRF focused on the 'Identification and Utilization of Robust Biomarkers in Type1 Diabetes', leaders in the field of type 1 diabetes (T1D)/autoimmunity and assay technology came together from academia, government and industry to assess the current state of the field, evaluate available resources/technologies and identify gaps that need to be filled for moving the field of T1D research forward. The highlights of this workshop are discussed in this paper, as well as the proposal for a larger, planned consortium effort, incorporating a JDRF Biomarker Core, to foster collaboration and accelerate progress in this critically needed area of T1D research.

Maternal health care in a rural area of Pakistan

OBJECTIVE

The need for effective strategies for delivery of healthcare to rural women is paramount and requires a study of maternal perceptions and experiences of the healthcare system.

METHOD

This article describes knowledge, attitudes and practices regarding obstetric healthcare in a rural area of Pakistan. This is a cross sectional survey of a rural area of district Hyderabad, Pakistan. A multistage sample of 1,150 households was drawn from a population of 247,257 living in 30,653 households. Structured KAP questionnaires regarding maternal health were administered to male and female respondents in study household.

RESULTS

A total of 1,178 married women and 1,146 married men were interviewed. The mean age of female respondents was 29 +/- 6 years. At the time of the interview 20% women were pregnant. Sixty-one percent women received antenatal care during their last pregnancy. The most frequent antenatal care providers were female doctors (55%). Majority (67%) of women had delivered at home with the assistance of traditional birth attendants (TBAs). Overall less than 40% of respondents could correctly identify signs of obstetric complications. Thirty-eight percent women experienced obstetric complications during their last pregnancy. Estimated annual maternal mortality ratio (MMR) was 689/100,000 live births.

CONCLUSION

Women have inadequate access to obstetric care due to limited healthcare options and poor knowledge of obstetric complications. This can be corrected by improving services and increasing overall maternal health awareness in the community.

Inhibition of IL-6 and IL-10 signaling and Stat activation by inflammatory and stress pathways

The development and resolution of an inflammatory process are regulated by a complex interplay among cytokines that have pro- and anti-inflammatory effects. Effective and sustained action of a proinflammatory cytokine depends on synergy with other inflammatory cytokines and antagonism of opposing cytokines that are often highly expressed at inflammatory sites. We analyzed the effects of the inflammatory and stress agents, IL-1, TNF-alpha, LPS, sorbitol, and H(2)O(2), on signaling by IL-6 and IL-10, pleiotropic cytokines that activate the Jak-Stat signaling pathway and have both pro- and anti-inflammatory actions. IL-1, TNF-alpha, and LPS blocked the activation of Stat DNA binding and tyrosine phosphorylation by IL-6 and IL-10, but not by IFN-gamma, in primary macrophages. Inhibition of Stat activation correlated with inhibition of expression of IL-6-inducible genes. The inhibition was rapid and independent of de novo gene induction and occurred when the expression of suppressor of cytokine synthesis-3 was blocked. Inhibition of IL-6 signaling was mediated by the p38 subfamily of stress-activated protein kinases. Jak1 was inhibited at the level of tyrosine phosphorylation, indicating that inhibition occurred at least in part upstream of Stats in the Jak-Stat pathway. Experiments using Stat3 mutated at serine 727 and using truncated IL-6Rs suggested that the target of inhibition is contained within the membrane-proximal region of the cytoplasmic domain of the gp130 subunit of the IL-6 receptor and is different from the SH2 domain-containing protein-tyrosine phosphatase/suppressor of cytokine synthesis-3 docking site. These results identify a new level at which IL-1 and TNF-alpha modulate signaling by pleiotropic cytokines such as IL-6 and IL-10 and provide a molecular basis for the previously described antagonism of certain IL-6 actions by IL-1.

Intratracheal administration of fentanyl: pharmacokinetics and local tissue effects

OBJECTIVE

To study the pharmacokinetics and local tissue effects resulting from the intratracheal administration of preservative-free fentanyl.

DESIGN

Prospective, randomized, blinded and controlled animal study.

SETTING

University research laboratory.

SUBJECTS

Eighteen adult male New Zealand rabbits.

INTERVENTIONS

Preservative-free fentanyl citrate or normal saline was administered by the intratracheal (i.t.) and intravenous (i.v.) routes to randomized groups of rabbits. The animals were killed at 24, 48 and 72 h following administration.

MEASUREMENTS AND MAIN RESULTS

Plasma concentrations of fentanyl were measured before administration and at 2, 5, 10, 30, 60 and 120 min following administration by a specific radioimmunoassay. A detailed histological examination of the lung and tracheal tissue was performed to identify local side effects. There were no significant differences in the plasma fentanyl concentrations resulting from the i.v. or i.t. route of administration. In both groups, the concentrations of fentanyl were within the therapeutic range (i.t. 2.37 ng/ml, i.v. 2.53 ng/ml) by 2 min after injection and reached a maximum concentration within 5 min. The bioavailability of i.t. fentanyl was 71%. Microscopic examination of the respiratory system did not show significant differences between the two random groups overall. However, in the sub-group of animals killed at 24 h, more animals in the i.t. group showed signs of inflammation in the lung parenchyma.

CONCLUSIONS

There is rapid absorption of fentanyl following i.t. administration. Pharmacokinetic parameters for fentanyl were not significantly altered by the route of administration. Although there were no signs that i.t. administration of preservative-free fentanyl produces lung injury, a transient and mild inflammatory response was detected at 24 h after administration.