Incidence of postoperative residual neuromuscular blockade - A multicenter, observational study in Portugal (INSPIRE 2)

Background

Although the use of neuromuscular blocking agents (NMBAs) optimizes surgical conditions and facilitates tracheal intubation, it can lead to residual neuromuscular blockade (RNMB), with postoperative complications. This study aimed to assess RNMB incidence and management in Portugal.

Methods

Prospective observational study of patients admitted for elective surgery requiring general anesthesia with nondepolarizing NMBAs between July 2018 and July 2019 at 10 Portuguese hospitals. The primary endpoint was the proportion of patients arriving at postanesthesia care unit (PACU) with a TOF ratio <0.9.

Results

A total of 366 patients were included, with a median age of 59 years, and 89.1% classified as ASA II or III. Rocuronium was the most used NMBA (99.5%). A total of 96.2% of patients received a reversal agent, 96.6% of which sugammadex and 3.4% neostigmine. Twenty patients displayed a TOF ratio <0.9 at PACU arrival, representing an RNMB incidence of 5.5% (95% CI, 3.1%-7.8%). Only two patients displayed a TOF ratio <0.7. RNMB incidence was 16.7% with neostigmine and 5.3% with sugammadex (P = .114). In patients with intraoperative neuromuscular blockade (NMB) monitoring, RNMB incidence was 5% (95% CI, 2%-8%), which varied significantly according to the type of monitoring (P = .018). Incidence of adverse events was 3.3% (2 severe and 10 moderate).

Conclusions

The reported overall incidence of 5.5% is numerically lower than results from similar observational studies. An appropriate pharmacological neuromuscular reversal strategy, guided by quantitative neuromuscular monitoring, has the potential to achieve even better results, converting RNMB from an unusual to a very rare or even inexistent event.

What do future public health doctors know about the One Health concept in Portugal?

Background

The One Health (OH) approach brings together a transdisciplinary collaboration between human, animal, and environmental health, to tackle emerging zoonotic diseases, antimicrobial resistance, and food safety. Therefore, incorporating of OH principles in the education of health care providers is fundamental.

Methods

To assess OH knowledge, attitudes and practices (KAP), an anonymous, multiple-choice, online self-administered survey was sent to 1st year Portuguese Public Health Medical Residents (PPHMR), during an online congress targeted to them. A descriptive analysis was performed.

Results

A 50.0% response rate was obtained out of the 42 PPHMR attendees. Only 33.3% were familiar with OH concept; 57,1% had heard of it but were not aware of its meaning, and 9.5% had never heard of it. Concerningly, 9,5% believed zoonosis were diseases transmitted between animals and 42.9% considered that “antimicrobial resistance” is applied to antibiotics only. Regarding major zoonosis, etiologic agents were not recognized for Cryptosporidiosis (47.6%), Echinococcosis (42.9%), Toxoplasmosis and Leptospirosis (38.1%), Dermatophytosis (33.3%), Rabies (28.6%), Borreliosis/Brucellosis (23.8%). Half (52.4%) were unaware of the transmission route of Brucellosis/Dermatophytosis, followed by Leptospirosis (38.1%), Toxoplasmosis (28.6%) and Borreliosis/Rabies (23.8%). Remarkably, all participants showed willingness to be informed on OH issues and agreed that prevention and speed of intervention would be higher with greater collaboration between health technicians. About education towards OH throughout their medical curricula, 61.9% classified it as low, 23.8% as absent, 14.3% as sufficient and none classified it as adequate or very adequate.

Conclusions

This is the first study assessing KAP regarding the OH concept among PPHMR. Results highlight the need to bring OH to the Portuguese medical schools’ agenda to better prepare the next generation of PPHMR to the emerging health crisis.

Key messages

• Despite the interest shown by 1st year Portuguese Public Health Medical Residents concerning One Health, a general lack of knowledge on the topic was found.

• The majority qualified as insufficient their training on this subject, highlighting the need for medical schools to improve education and raise awareness regarding this transdisciplinary approach.

Validation of the Portuguese Version of the Postoperative Quality Recovery Scale (PostopQRS)

INTRODUCTION

The Postoperative Quality Recovery Scale is a brief instrument of six domains designed to assess quality of recovery from early to long term after surgery. This study aims to validate the Portuguese version of the Postoperative Quality Recovery Scale.

MATERIAL AND METHODS

In this observational study 101 adult patients undergoing elective surgery completed the Postoperative Quality Recovery Scale at 15 minutes and 40 minutes, one and three days after surgery. Three constructs were assessed for validity: increased recovery over time; effect of gender and recovery association with muscle strength. Reliability, responsiveness, feasibility and acceptability were also assessed.

RESULTS

Construct validity was shown by increased recovery over time; worse recovery for female patients in emotive, nociceptive, activities of daily living and overall recovery; improved muscle strength in recovered patients. Internal consistency for activities of daily living was acceptable at all-time points (Cronbach's α value of 0.772 or higher), indicating scale reliability. The scale was able to detect differences in postoperative quality of recovery between the neuromuscular blockade reversal agents, neostigmine and sugammadex, indicating scale responsiveness. The time to conduct the Portuguese version at baseline was 95 - 581 seconds (median 319 seconds) and it was reduced with subsequent assessments. The proportion of patients completing all scale items was 87%, 75%, 65% and 94% for the four time periods evaluated, indicating scale feasibility and acceptability.

DISCUSSION

This study shows that the Portuguese version of the Postoperative Quality Recovery Scale, demonstrates construct validity, reliability, responsiveness, feasibility and acceptability.

CONCLUSIONS

This study allowed validation of the Portuguese version of the Postoperative Quality Recovery Scale.

[CR-POSSUM and Surgical Apgar Score as predictive factors for patients' allocation after colorectal surgery]

BACKGROUND AND OBJECTIVES

Surgical patients frequently require admission in high-dependency units or intensive care units. Resources are scarce and there are no universally accepted admission criteria, so patients' allocation must be optimized. The purpose of this study was to investigate the relationship between postoperative destination of patients submitted to colorectal surgery and the scores ColoRectal Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (CR-POSSUM) and Surgical Apgar Score (SAS) and, secondarily find cut-offs to aid this allocation.

METHODS

A cross-sectional prospective observational study, including all adult patients undergoing colorectal surgery during a 2 years period. Data collected from the electronic clinical process and anesthesia records.

RESULTS

A total of 358 patients were included. Median score for SAS was 8 and CR-POSSUM had a median mortality probability of 4.5%. Immediate admission on high-dependency units/intensive care units occurred in 51 patients and late admission in 18. Scores from ward and high-dependency units/intensive care units patients were statistically different (SAS: 8 vs. 7, p<0.001; CR-POSSUM: 4.4% vs. 15.9%, p<0.001). Both scores were found to be predictors of immediate postoperative destination (p<0.001). Concerning immediate high-dependency units/intensive care units admission, CR-POSSUM showed a strong association (AUC 0.78, p=0.034) with a ≥9.16 cut-off point (sensitivity: 62.5%; specificity: 75.2%), outperforming SAS (AUC 0.67, p=0.048), with a ≤7 cut-off point (sensitivity: 67.3%; specificity: 56.1%).

CONCLUSIONS

Both CR-POSSUM and SAS were associated with the clinical decision to admit a patient to the high-dependency units/intensive care units immediately after surgery. CR-POSSUM alone showed a better discriminative capacity.

How many people will need palliative care in 2040? Past trends, future projections and implications for services

BACKGROUND

Current estimates suggest that approximately 75% of people approaching the end-of-life may benefit from palliative care. The growing numbers of older people and increasing prevalence of chronic illness in many countries mean that more people may benefit from palliative care in the future, but this has not been quantified. The present study aims to estimate future population palliative care need in two high-income countries.

METHODS

We used mortality statistics for England and Wales from 2006 to 2014. Building on previous diagnosis-based approaches, we calculated age- and sex-specific proportions of deaths from defined chronic progressive illnesses to estimate the prevalence of palliative care need in the population. We calculated annual change over the 9-year period. Using explicit assumptions about change in disease prevalence over time, and official mortality forecasts, we modelled palliative care need up to 2040. We also undertook separate projections for dementia, cancer and organ failure.

RESULTS

By 2040, annual deaths in England and Wales are projected to rise by 25.4% (from 501,424 in 2014 to 628,659). If age- and sex-specific proportions with palliative care needs remain the same as in 2014, the number of people requiring palliative care will grow by 25.0% (from 375,398 to 469,305 people/year). However, if the upward trend observed from 2006 to 2014 continues, the increase will be of 42.4% (161,842 more people/year, total 537,240). In addition, disease-specific projections show that dementia (increase from 59,199 to 219,409 deaths/year by 2040) and cancer (increase from 143,638 to 208,636 deaths by 2040) will be the main drivers of increased need.

CONCLUSIONS

If recent mortality trends continue, 160,000 more people in England and Wales will need palliative care by 2040. Healthcare systems must now start to adapt to the age-related growth in deaths from chronic illness, by focusing on integration and boosting of palliative care across health and social care disciplines. Countries with similar demographic and disease changes will likely experience comparable rises in need.

Zinc nanostructures for oxygen scavenging

In this work, oxidation of carbon supported Zn nanostructures was studied to elucidate their utilization as oxygen scavenging materials activated by the relative humidity in the environment. Moisture-activated nano-scavengers were produced on carbon substrates using magnetron sputtering attaining nano-islands (nanoparticles), randomly distributed on the carbon surface, with arbitrary crystallographic orientations. They possess a Zn-ZnO core-shell structure, caused by surface passivation, which provides them with a self-assembled protective layer that prevents complete oxidation of nanoparticles prior to utilization. The oxidation rate is independent of the nanoparticle size and orientation, for particles between 5 and 18 nm. The oxidation kinetics are not in complete agreement with the Cabrera and Mott theory. When exposed to a high relative humidity environment, an acceleration in the oxidation process is observed, dissolving the Zn nanoparticles and forming a layer on the carbon, which facilitates the consumption of the Zn to form ZnO. These results support the idea of its potential use in applications where high RH environments are required, such as food packaging.

Perioperative Predictors of Survival After Liver Transplantation for Familial Amyloid Polyneuropathy in a Portuguese Center

BACKGROUND

Liver transplantation (LT) has been the treatment of choice to halt the progression of familial amyloid polyneuropathy (FAP). Few studies have identified prognostic factors for post-LT survival in FAP. Our aim was to assess survival rate and to identify independent factors for survival after LT.

METHODS

This retrospective cohort study of FAP patients transplanted for the first time analyzed 116 transplantations from 2006 to 2014. The median follow-up period was 45.5 months.

RESULTS

The overall survival rates at 1 month, 1 year, and 5 years were 89%, 82% and 79%, respectively. On multivariate analysis, only number of red blood cell (RBC) units transfused during surgery, operation time, and body mass index were independent prognostic factors for patient survival. Only 30% of patients were transfused during surgery, and, in these, each RBC unit transfused increased mortality by 53%. The operation time increased mortality by 20% for every 15 minutes of surgery.

CONCLUSIONS

This study suggests that operation time and RBC transfused are predominant factors affecting post-LT survival in our FAP patients.

Ilizarov tibial lengthening in the skeletally immature patient

AIMS

We wished to examine the effectiveness of tibial lengthening using a two ring Ilizarov frame in skeletally immature patients. This is a potentially biomechanically unstable construct which risks the loss of axial control.

PATIENTS AND METHODS

We retrospectively reviewed a consecutive series of 24 boys and 26 girls, with a mean age of 8.6 years (4 to 14), who underwent 52 tibial lengthening procedures with a mean follow-up of 4.3 years (4.0 to 16.9). Tibial alignment was measured before and after treatment using joint orientation lines from the knee and a calculation of the oblique plane axis.

RESULTS

The mean percentage length gain was 20% (13 to 31) with a mean bone-healing index (BHI) of 34 days per centimetre (20 to 54). Age at surgery and location of the osteotomy site showed a strong relationship as the location of the osteotomy migrated more proximally with age. However, no significant correlation was found between BHI and the position of the osteotomy. The coronal and sagittal joint orientation of the lengthened tibias were within the normal range in 67% and 92% of cases, respectively. The oblique plane angulation calculation revealed a statistically significant change pre- to post-operatively in both magnitude (p < 0.05) and direction (p < 0.01), but without clinical consequence. The majority of complications were minor (n = 40 in 27 patients; 1.48 complications per segment lengthened) with no residual disability reported.

CONCLUSION

Two-ring tibial lengthening is effective in maintaining segmental alignment, efficient in callous production and relatively comfortable for the patient with few significant complications. Cite this article: Bone Joint J 2016;98-B:1276-82.

Complexing Aβ prevents the cellular anomalies induced by the Peptide alone

Retention of intracellular secreted APP (isAPP) can be provoked by the neurotoxic peptide Aβ. The latter decreases in the cerebrospinal fluid of Alzheimer’s disease (AD) patients, as a consequence of its cerebral accumulation and deposition into senile plaques. Of similar relevance, secreted APP (sAPP) levels can be associated with AD. The studies here presented, reinforce the link between sAPP and Aβ and address putative therapeutic strategies. Laminin and gelsolin are potential candidates; both prevent Aβ fibril formation by complexing with Aβ, thus attenuating its neurotoxicity. We show that preincubation of Aβ with laminin and gelsolin has the effect of rendering it less potent to isAPP accumulation in cortical neurons. This appears to be related to a decrease in F-actin polymerization, whereas Aβ alone induces the polymerization. Further, Aβ decreases gelsolin levels, and the latter is involved in Aβ removal. Our data indicates that Aβ-laminin and Aβ-gelsolin complexes are less neurotoxic and also less potent than fibrillar Aβ at inducing isAPP retention. These results validate the potential of these proteins as therapeutic strategies that prevent the Aβ-induced effects. In hence, given that Aβ decreases the levels of proteins involved in its own clearance, this may contribute to the mechanisms underlying AD pathology.

Geographic population structure of the African malaria vector Anopheles gambiae suggests a role for the forest-savannah biome transition as a barrier to gene flow

The primary Afrotropical malaria mosquito vector Anopheles gambiae sensu stricto has a complex population structure. In west Africa, this species is split into two molecular forms and displays local and regional variation in chromosomal arrangements and behaviors. To investigate patterns of macrogeographic population substructure, 25 An. gambiae samples from 12 African countries were genotyped at 13 microsatellite loci. This analysis detected the presence of additional population structuring, with the M-form being subdivided into distinct west, central, and southern African genetic clusters. These clusters are coincident with the central African rainforest belt and northern and southern savannah biomes, which suggests restrictions to gene flow associated with the transition between these biomes. By contrast, geographically patterned population substructure appears much weaker within the S-form.

If you had less than a year to live, would you want to know? A seven-country European population survey of public preferences for disclosure of poor prognosis

OBJECTIVE

With increasing European cancer deaths, clinicians must manage information regarding poor prognosis. This study aimed to determine European citizens' preferences, within a scenario of serious illness such as cancer with less than a year to live, for information disclosure regarding poor prognosis, the likely symptoms and problems, and the care options available, to measure variations between countries and to identify factors associated with preferences.

METHODS

A population-based cross-national telephone survey using random digit dialling in seven countries was conducted.

RESULTS

Among 9344 respondents, data revealed an international preference (73.9%) to always be informed in the scenario of having a serious illness such as cancer with less than a year to live. This varied from 67.6% in Italy to 80.7% in Flanders. A minority (21.1%) did not want such information unless they ask, or at all. People younger than 70 years (OR 0.72, 95% CI 0.62-0.83, p < 0.001), men (OR 1.23, 95% CI 1.10-1.37, p < 0.001), those with experience of illness (OR = 1.20. 95% CI 1.01-1.43, p < 0.05) and with more education (OR = 1.20, 95% CI 1.09-1.32, p < 0.001) were more likely to want to know of limited time left.

CONCLUSIONS

The models confirmed the influence of four factors in more than one country (age, gender, education and most concerning problem) and added 11 country-specific factors to which national policies and clinical practice should respond. These findings confirm a majority public preference to be informed in a scenario of poor prognosis. Policy clinical practice should facilitate elucidation and delivery of preferences. Evidence for effective communication skills-building interventions for clinicians is required.

Effect of chromosome constitution variations on the expression of Turner phenotype

Turner syndrome (TS) is a chronic disease related to haploinsufficiency of genes that are normally expressed in both X chromosomes in patients with female phenotype that is associated with a wide range of somatic malformations. We made detailed cytogenetic and clinical analysis of 65 patients with TS from the region of Recife, Brazil, to determine the effects of different chromosome constitutions on expression of the TS phenotype. Overall, patients with X-monosomy exhibited a tendency to have more severe phenotypes with higher morbidity, showing its importance in TS prognosis. Additionally, we found rare genetic and phenotypic abnormalities associated with this syndrome. To the best of our knowledge, this is the first case of 45,X,t(11;12)(q22;q22) described as a TS karyotype. Turner patients usually have normal intelligence; however, moderate to severe levels of mental retardation were found in 5 TS cases, which is considerate a very uncommon feature in this syndrome.

Preferences for place of death if faced with advanced cancer: a population survey in England, Flanders, Germany, Italy, the Netherlands, Portugal and Spain

BACKGROUND

Cancer end-of-life care (EoLC) policies assume people want to die at home. We aimed to examine variations in preferences for place of death cross-nationally.

METHODS

A telephone survey of a random sample of individuals aged ≥16 in England, Flanders, Germany, Italy, the Netherlands, Portugal and Spain. We determined where people would prefer to die if they had a serious illness such as advanced cancer, facilitating circumstances, personal values and experiences of illness, death and dying.

RESULTS

Of 9344 participants, between 51% (95% CI: 48% to 54%) in Portugal and 84% (95% CI: 82% to 86%) in the Netherlands would prefer to die at home. Cross-national analysis found there to be an influence of circumstances and values but not of experiences of illness, death and dying. Four factors were associated with a preference for home death in more than one country: younger age up to 70+ (Germany, the Netherlands, Portugal, Spain), increased importance of dying in the preferred place (England, Germany, Portugal, Spain), prioritizing keeping a positive attitude (Germany, Spain) and wanting to involve family in decisions if incapable (Flanders, Portugal).

CONCLUSIONS

At least two-thirds of people prefer a home death in all but one country studied. The strong association with personal values suggests keeping home care at the heart of cancer EoLC.

Slipped capital femoral epiphysis: rising rates with obesity and aboriginality in South Australia

We analysed the incidence of slipped capital femoral epiphysis (SCFE) in South Australia, investigating possible associations between an increased incidence of SCFE, the local indigenous population and the Australian obesity epidemic during the last 20 years. Data including race, age and gender were collected to obtain a profile of the South Australian SCFE patient, and were then compared with epidemiological data for South Australian adolescents. We concluded that the incidence of both obesity and SCFE is increasing. We also noted that the median weight of SCFE patients has increased and the mean age at diagnosis has decreased. Despite weight profiles comparable with those of the general population, we noted that an indigenous child was three times more likely to develop SCFE than a non-indigenous child. As far as we know there is no published literature on the predisposition of Aboriginal Australians to SCFE.

Orally active trifluoromethyl ketone inhibitors of human leukocyte elastase

This paper describes the development a series of peptidyl trifluoromethyl ketone inhibitors of human leukocyte elastase which are found to have excellent pharmacological profiles. Methods have been developed that allow for the synthesis of these inhibitors in stereochemically pure form. Two of these compounds, 1k and 1l, have high levels of oral bioavailability in several species. Compound 1l has entered development as ZD8321 and is presently undergoing clinical evaluation. These compounds demonstrate that peptidyl trifluoromethyl ketone inhibitors can achieve high levels of oral activity and bioavailability, and therefore they may prove useful as therapeutic agents in the treatment of diseases in which elastase is implicated.

Discovery and biological activity of orally active peptidyl trifluoromethyl ketone inhibitors of human neutrophil elastase

Previously we had shown that tripeptidyl trifluoromethyl ketones (TFMKs) possessing an N-terminal diarylacylsulfonamide, such as ICI 200,880 and ICI 200,355, displayed unparalleled protection against the lung damage induced by human neutrophil elastase (HNE) when the inhibitors were administered intratracheally. Since the diarylacylsulfonamides were designed specifically to afford a long residence time in the lung, it was not unexpected that inhibitors from this class of TFMKs were not active when administered orally. Upon evaluating a large number of peptidyl TFMKs possessing a variety of N-terminal groups, several compounds were identified which demonstrated oral activity. Compounds were evaluated for their oral activity by measuring their ability to inhibit the increase in lung weight relative to body weight (Lw/Bw), the increase in red blood cells, and the increase in white blood cells induced by intratracheally administered HNE (100 micrograms/hamster). A number of tripeptidyl trifluoromethyl ketones containing neutral N-terminal groups displayed good oral activity, while those containing basic, acidic, or polar groups did not. Compound 50, possessing an N-terminal 4-(CH3O)C6H4CO group, was particularly effective, reducing Lw/Bw by 77%, red cells by 89%, and white cells by 91% when dosed at 37.5 mg/kg orally. Thus, by modifying the N-terminal group of tripeptidyl TFMKs, inhibitors can be designed which are effective in vivo when administered either orally or intratracheally.

Nonpeptidic inhibitors of human neutrophil elastase. 7. Design, synthesis, and in vitro activity of a series of pyridopyrimidine trifluoromethyl ketones

Using molecular modeling and the information derived from X-ray crystal structures of human neutrophil elastase (HNE) and porcine pancreatic elastase (PPE) complexed to peptidic ligands, we have developed a new series of nonpeptidic inhibitors of HNE, the pyridopyrimidine trifluoromethyl ketones (TFMKs). These bicyclic inhibitors were designed to extend the concept of the related pyridone trifluoromethyl ketones by incorporating a rigidly positioned carbonyl group to participate in a hydrogen bonding interaction with the backbone NH groups of Gly-218 and Gly-219 of the enzyme. In addition, the pyrimidine ring serves as a scaffold to vector substituents toward the S5-S4 subsites of the enzyme's extended binding pocket. Furthermore, the heteroatoms of the pyrimidine ring generally increase the aqueous solubility of the pyridopyrimidines relative to pyridone TFMKs. Pyridopyrimidine TFMKs containing a 6-phenyl substituent afforded potent inhibitors of elastase, and several inhibitors from this class of compounds possessed aqueous solubilities of > 0.1 mg/mL and Ki values of < or = 10 nM.

Nonpeptidic inhibitors of human leukocyte elastase. 5. Design, synthesis, and X-ray crystallography of a series of orally active 5-aminopyrimidin-6-one-containing trifluoromethyl ketones

The effects of changes in substitution in a series of 5-amino-2-pyrimidin-6-ones on both in vitro activity and oral activity in an acute hemorrhagic assay have been explored. These compounds contained either a trifluoromethyl ketone or a boronic acid moiety to bind covalently to the Ser-195 hydroxyl of human leukocyte elastase (HLE). Boronic acid-containing inhibitors were found to be more potent than the corresponding trifluoromethyl ketones in vitro but were less active upon oral administration. Compound 13b was found to offer the best combination of oral potency, duration of action, and enzyme selectivity and, as such, was selected for further biological testing. X-ray crystallography of a cocrystallized complex of compound 19m and porcine pancreatic elastase demonstrated that the inhibitor is bound to the enzyme in a manner similar to that found previously for a closely related series of pyridone-containing inhibitors of HLE.

Non-peptidic inhibitors of human leukocyte elastase. 4. Design, synthesis, and in vitro and in vivo activity of a series of beta-carbolinone-containing trifluoromethyl ketones

A novel series of human leukocyte elastase (HLE) inhibitors containing the beta-carbolinone ring system are reported. The design of these trifluoromethyl ketone-based inhibitors used a combination of structural information obtained from X-ray crystallography and molecular modeling investigations. The beta-carbolinone ring in these compounds serves as a highly efficient peptidiomimetic for the P2-P3 region of peptidyl trifluoromethyl ketone inhibitors of HLE. Several of the beta-carbolinones exhibit significant in vitro potency, with Ki values in the nanomolar range. Using aqueous molecular dynamics simulations, realistic models for the molecular recognition of these inhibitors by HLE have been obtained and are discussed. This series of compounds are found to have excellent selectivity for HLE over a number of other proteolytic enzymes, including closely related enzymes such as porcine pancreatic elastase.

Non-peptidic inhibitors of human leukocyte elastase. 1. The design and synthesis of pyridone-containing inhibitors

Human leukocyte elastase (HLE) is a serine protease produced by neutrophils that has been implicated in diseases such as emphysema and cystic fibrosis. An HLE inhibitor may have therapeutic value in these diseases. An active site model of HLE bound to a tripeptidic trifluoromethyl ketone (TFMK) inhibitor, 2, was created from X-ray structures of HLE and porcine pancreatic elastase. Analysis of the model indicated a preferred binding conformation for the tripeptide and potentially important interactions between it and the enzyme. This information was used to aid in the design of a series of novel, pyridone-containing, non-peptidic HLE inhibitors such as 2-[3-[[(benzyloxy)carbonyl]amino]-2-oxo- 1,2-dihydro-1-pyridyl]-N-(3,3,3-trifluoro-1-isopropyl-2-oxopropyl)ace tam ide (5b) (Ki = 280 +/- 78 nM). Inspection of the active site model suggested that a benzyl substituent at the 5-position of the pyridone ring might improve potency by forming a lipophilic interaction with the enzyme S2 pocket. Synthesis and biological evaluation of a series of 5-benzylpyridone TFMKs provided evidence for this proposition. Further analysis of the model indicated that substitution on the 3-amino group of the pyridone ring with a hydrogen bond acceptor could potentially lead to interactions with the NH atoms of glycine-218 and/or -219. The oxalate derivative 2-[5-benzyl- 3-(carboxycarbonyl)-2-oxo-1,2-dihydro-1-pyridyl]-N-(3,3,3-trifl uor o-1- isopropyl-2-oxopropyl)acetamide (5v) was synthesized and found to have a Ki of 48 +/- 9 nM. Unfortunately, none of the compounds tested was active in an in vivo model of HLE-induced lung injury when dosed orally.