Tourniquet Use in Extremity-Based Microsurgery

BACKGROUND

 The use of tourniquets and their role in extremity-based microsurgery has not been thoroughly investigated. The purpose of this study was to investigate tourniquet use and its associated outcomes and complications. The authors hypothesize that tourniquets enhance visualization, bloodless approaches to vessel harvest, flap elevation, and anastomosis without added complications.

METHODS

 A retrospective chart review was completed for patients who had undergone extremity-based microsurgery with the use of a tourniquet between January 2018 and February 2022 at two large academic institutions. Demographic characteristics, initial reasons for surgery, complications, and outcomes were recorded. Patients were separated into groups based on tourniquet use during three operative segments: (1) flap elevation, (2) vessel harvest, and (3) microvascular anastomosis. An internal comparison of complication rate was performed between cases for which a tourniquet was used for one operative segment to all cases in which it was not used for the same operative segment. Univariate and multivariate statistical analyses were performed to identify statistically significant results.

RESULTS

 A total of 99 patients (106 surgeries) were included in this study across sites. The mean age was 41.2 years and 67.7% of the patients were male. The most common reason for microsurgical reconstruction was trauma (50.5%). The need for an additional unplanned surgery was the most common surgical complication (16%). A total of 70, 61, and 32% of procedures used a tourniquet for flap elevation, vessel harvest, and for anastomosis, respectively. Statistical analyses identified no difference in complication rates for procedures for which a tourniquet was or was not used for interventions.

CONCLUSION

 Based on these results, the authors state that tourniquets can be utilized for extremity-based microsurgery to enable bloodless dissection without the concern of increased complication rates.

MBSAQIP database: are the data reliable?

BACKGROUND

The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database collects data from all accredited centers in the US. A prior study showed data quality issues limiting use of up to 20% of the 2015 database.

OBJECTIVES

To evaluate the completeness and data quality (internal validity, accuracy, and consistency) of the MBSAQIP database between 2015 and 2019.

SETTING

United States.

METHODS

All subsets of data from the MBSAQIP Participant User Data File (PUDF) were compiled into one main file. Completeness, internal validity, accuracy, and consistency were evaluated. Completeness was determined via missing values. Internal validity was assessed using the percentage of patients with a body mass index (BMI) < 30 kg/m2 who underwent primary bariatric surgery. Accuracy was evaluated using reported versus calculated BMI. Consistency was assessed using the percentage of patients with a gain of >5 or a loss of >20 units of BMI change in 30 days. Effects across years were assessed using a chi-squared test.

RESULTS

Missing data for age, BMI, and ASA was consistently low (<2.5%) with no significant difference across years. Only .02% of patients who underwent a primary bariatric procedure had a reported BMI <30 kg/m2. The mean difference between reported versus calculated BMI was -.02 units. A maximum of .33% of patients gained >5 units of BMI, and a maximum of .85% of patients lost > 20 units of BMI in early follow-up.

CONCLUSIONS

While the MBSAQIP is a database with acceptable data quality and minimal changes from 2015-2019, ongoing efforts are needed to improve data.

American Society for Metabolic and Bariatric Surgery 2022 estimate of metabolic and bariatric procedures performed in the United States

BACKGROUND

Metabolic and bariatric surgery (MBS), despite being the most effective durable treatment for obesity, remains underused as approximately 1% of all qualified patients undergo surgery. The American Society for Metabolic and Bariatric Surgery established a Numbers Taskforce to specify the annual rate of obesity treatment interventions utilization and to determine if patients in need are receiving appropriate treatment.

OBJECTIVE

To provide the best estimated number of metabolic and bariatric procedures being performed in the United States in 2022.

SETTING

United States.

METHODS

We reviewed data from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program and National Surgical Quality Improvement Program. In addition, data from industry and state databases were used to estimate activity at non-accredited centers. Data from 2022 were compared mainly with data from the previous 2 years.

RESULTS

Compared with 2021, the total number of MBS performed in 2022 increased from approximately 262,893 to 280,000. The sleeve gastrectomy (SG) continues to be the most commonly performed procedure. The gastric bypass procedure trend remained relatively stable. The percentage of revision procedures and biliopancreatic diversion with duodenal switch procedures increased slightly. Intragastric balloon placement increased from the previous year. Endoscopic sleeve gastroplasty increased in numbers.

CONCLUSIONS

There was a 6.5% increase in MBS volume from 2021 to 2022 and a 41% increase from 2020, which demonstrates a recovery from the COVID-19 pandemic. SG continues to be the most dominant MBS procedure.

Content Validity Testing of a Novel Cognitive Screen, the Gaylord Occupational Therapy Cognitive (GOT-Cog), to Improve Inpatient Occupational Therapy Treatment Planning

IMPORTANCE

No single cognitive screen adequately captures all cognitive domains that are important for inpatient occupational therapy treatment planning.

OBJECTIVE

To quantify the content validity of a novel 22-item cognitive screen, the Gaylord Occupational Therapy Cognitive (GOT-Cog) screen, developed to better inform inpatient occupational therapy treatment planning.

DESIGN

Delphi-style expert panel review.

SETTING

Long-term acute care hospital.

PARTICIPANTS

The first panel was attended by four occupational therapists, two speech-language pathologists, one physician assistant, and two neuropsychologists; the second, by four occupational therapists, one speech-language pathologist, and one physician assistant.

INTERVENTION

Each Delphi panel discussed the relevance, essentiality, and clarity of each item. After each discussion, panelists completed a content validity survey to summarize their evaluation of each item.

OUTCOMES AND MEASURES

On the basis of panelists' survey responses, item- and scale-level relevance, essentiality, and clarity were quantified by calculating the respective content validity index (CVI), content validity ratio (CVR), and content clarity index (CCI). Universal agreement (UA) and κ statistics were also calculated, as appropriate.

RESULTS

Upon presenting the initial 23-item instrument covering 10 cognitive domains to the first Delphi panel, several questions were added, removed, or rewritten, resulting in a 22-item instrument representing nine domains. After the second panel, several questions were again rewritten, and the domains reorganized. All scale-level metrics improved, including CVI (from 0.87 to 1.0), UA (0.52 to 1.0), CVR (0.43 to 0.94), and CCI (2.26 to 2.92).

CONCLUSIONS AND RELEVANCE

GOT-Cog displays overall excellent content validity and can proceed to construct validity testing. Plain-Language Summary: By reporting on the content validity of the Gaylord Occupational Therapy Cognitive screen, this brief report begins the necessary process of evaluating the measure's overall validity and reliability.

Third time's a charm: band to sleeve to bypass

BACKGROUND

Adjustable gastric bands (AGB) are frequently converted to sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB) due to weight recurrence or band complications. Such conversions carry a higher-risk than primary procedures. Some patients undergo two conversions-from AGB to SG, and subsequently from SG to RYGB. This presents a unique situation with limited literature on indications and complication rates associated with these double conversions.

METHODS

We examined the 2020-2021 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) Participant Use File to evaluate conversions from AGB to SG and then to RYGB. Patient and operative characteristics, along with outcomes, were evaluated. Descriptive statistics were applied.

RESULTS

We identified 276 patients who underwent a conversion from AGB to SG and then to RYGB. The primary reason for the second conversion (SG to RYGB) was gastroesophageal reflux disease (GERD) at 55.1%, followed by inadequate weight loss or weight regain (IWL/WR) at 36.9%. The remaining reasons included dysphagia, nausea, vomiting, or others. Patients converted for IWL/WR demonstrated a higher baseline body mass index and prevalence of sleep apnea compared to other cohorts (both p < 0.001). Meanwhile, patients in the "other reasons" group had the highest rate of open surgical approaches (9.1%) and concurrent lysis of adhesions (p = 0.001 and p = 0.022), with correspondingly higher rates of anastomotic leak, reoperations, serious complications, and mortality.

CONCLUSIONS

Patients undergoing double conversions (AGB to SG to RYGB) do so primarily for GERD or IWL/WR. Further research is required to better define the optimal primary operation for each patient, aiming to reduce the necessity for multiple conversions.

Molecular biomarkers for assessing the heat-adapted phenotype: a narrative scoping review

Heat acclimation/acclimatisation (HA) mitigates heat-related decrements in physical capacity and heat-illness risk and is a widely advocated countermeasure for individuals operating in hot environments. The efficacy of HA is typically quantified by assessing the thermo-physiological responses to a standard heat acclimation state test (i.e. physiological biomarkers), but this can be logistically challenging, time consuming, and expensive. A valid molecular biomarker of HA would enable evaluation of the heat-adapted state through the sampling and assessment of a biological medium. This narrative review examines candidate molecular biomarkers of HA, highlighting the poor sensitivity and specificity of these candidates and identifying the current lack of a single 'standout' biomarker. It concludes by considering the potential of multivariable approaches that provide information about a range of physiological systems, identifying a number of challenges that must be overcome to develop a valid molecular biomarker of the heat-adapted state, and highlighting future research opportunities.

When do leaks occur? An analysis of the metabolic and bariatric surgery accreditation and quality improvement program

BACKGROUND

Leak is a feared complication of bariatric surgeries. Time to presentation is important in their management. We used the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) to evaluate the rate and timing of leaks.

OBJECTIVES

To determine when leaks present after bariatric surgery.

SETTING

MBSAQIP database.

METHODS

The MBSAQIP Participant Use Files (PUF) for the years 2015-2020 were evaluated. Outcomes of interest were "organ space infection" and "leak." We evaluated the time to presentation for these variables as well as patient characteristics, operative time, complication rates and 30-day outcomes.

RESULTS

There were 370,369 sleeve gastrectomies (SG) and 159,280 Roux-en-Y gastric bypasses (RYGB). We identified 598 (.16%) SG leaks with an average time to presentation of 13.2 ± 7.8 days. For RYGB, there were 520 leaks (.32%) with an average time to presentation of 9.5 ± 7.4 days. Both procedures had longer operative times for the patients with leak; RYGB was 115 minutes versus 131 minutes and SG was 67 minutes versus 77 minutes (both P < .01). SG and RYGB patients with a leak had a higher relative risk (RR) of grade 4 and 5 Clavien-Dindo complication rates. RR of mortality rates in SG patients with leak was 35.2 (confidence interval (CI): 20-61) and in RYGB with leak was 31.4 (CI: 19-50).

CONCLUSIONS

The length of time for SG leak presentation was more delayed than RYGB leak presentation. Surgeons should be vigilant for leaks for at least 3 weeks after surgery. Leaks increase the mortality rate and overall serious complications.

Early Bowel Obstruction after Bariatric Surgery: An Analysis of the 2020-2021 MBSAQIP Database

BACKGROUND

The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program evaluates 30-day outcomes of bariatric cases performed in the United States. The Participant Use File in 2020 introduced bowel obstruction (BO). We compared the rates of BO, risk factors, and postoperative outcomes after laparoscopic Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and duodenal switch (DS).

METHODS

Retrospective analysis of patients who underwent laparoscopic RYGB, SG, or DS obtained from the 2020-2021 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program. Patients who underwent either as a primary procedure with a body mass index >35 kg/m 2 were selected. Baseline characteristics, operative details, and postoperative complications were collected. The outcome of interest was BO occurring within 30 days.

RESULTS

A total of 205,533 cases of which 148,944 were SG (72.4%), 54,606 were RYGB (26.5%), and 1983 were DS (1%). BO occurred in 0.74%, 0.4%, and 0.03% of patients who underwent an RYGB, DS, or SG, respectively. Patients with a BO in the RYGB group were more likely to be on immunosuppressive therapy (5.4% vs. 1.9%, P <0.001) with longer operative time (136.2 min±58.0 min vs. 117.4 min±53.6 min, P <0.001). SG patients with a BO were older (47.5±13.6 vs. 41.9±11.6, P =0.011) with longer operating times (98.6±63.8 vs. 68.9±33.4, P =0.002). Patients in the RYGB group with a BO had the highest rates of readmissions (71.9%) and reoperations (58.4%).

CONCLUSIONS

Early bowel obstruction is rare after bariatric surgery. It is more common after RYGB and least common after SG. Readmission and reoperation rates were highest in patients with BO in the RYGB group.

First Measurement of the Nuclear-Recoil Ionization Yield in Silicon at 100 eV

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

One Anastomosis Gastric Bypass Versus Single Anastomosis Duodenoileostomy with Sleeve: Comparative Analysis of 30-Day Outcomes Using the MBSAQIP

INTRODUCTION/PURPOSE

One anastomosis gastric bypass (OAGB) and single anastomosis duodenoileostomy with sleeve (SADI-S) are two highly effective bariatric procedures that have been recently endorsed by the American Society of Metabolic and Bariatric Surgery (ASMBS). We compared the outcomes and safety profiles of SADI-S and OAGB using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database.

MATERIALS AND METHODS

Retrospective analysis on patients who underwent SADI-S or OAGB obtained from the MBSAQIP database 2020-2021. Patients who underwent concurrent procedures (besides EGD) or had missing data were removed. Variables included age, sex, body mass index, American Society of Anesthesiologists (ASA) class, and pertinent medical comorbidities. Data were analyzed for 30-day postoperative morbidity, mortality, reoperation, reintervention, and readmissions. p values were calculated using Student's t-test or Fisher analysis.

RESULTS

A total of 694 and 1068 patients respectively underwent SADI-S or OAGB. Statistically significant comorbidities included age (42.2 ± 10.8 vs. 43.7 ± 12.2), BMI (50.6 ± 9.1 vs. 45.3 ± 7.1), ASA 2 (66 (9.5%) vs. 165 (15.4%)), ASA 4 [69 (9.9%) vs. 20 (1.9%)], and immunosuppressive therapy [24 (3.5%) vs. 17 (1.6%)]. Clavien-Dindo-based analysis highlighted that SADI-S had higher grade 2 (p = 0.005) and grade 4b (p = 0.001) complications. Patients who underwent SADI-S were twice as likely to be readmitted within 30 days (3.7% vs. 1.9%; p = 0.021).

CONCLUSION

SADI-S had higher readmission rates and higher Clavien-Dindo grade 2 and 4b complications. To note, SADI-S patients had higher BMIs. Further studies are needed to determine the long-term complications and efficacy of both operations.

Effect of operative times in bariatric surgery on outcomes: a matched analysis of the MBSAQIP database

BACKGROUND

The implications of operative time (OT) have been studied in different surgical specialties, showing a correlation with higher incidence rates of postoperative complications. However, the impact of OT on bariatric surgery complications is not well elucidated.

METHODS

A retrospective review of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database between 2015 and 2019 was performed. A total of 358,382 SG patients and 123,357 RYGB patients were included. The median OT was 68 min (10-720) and 113 min (10-640) for the sleeve gastrectomy (SG) group and the Roux-en-Y gastric bypass group, respectively. The groups were subdivided into two subgroups based on OT in comparison to the median time of each group. The subgroups were compared for surgical complications and outcomes. To reduce selection bias and risk of confounders, we performed a propensity score matching (PSM) for 22 variables.

RESULTS

In the PSM-matched cohort, 18,915 SG and 6,495 RYGB patients were included in each subgroup. The SG cohort showed higher rates of Clavien-Dindo Class 1, 2, 3a, 4, and 5 complications as well as higher rates of readmission, reoperation, and reintervention in the longer OT group before matching. After PSM, the subgroup with longer times continued to have higher rates of Clavien-Dindo Class 2 complications and higher rates of readmission and reoperation. Similarly, there were higher rates of all Clavien-Dindo class complications as well as readmission, reoperation, and reintervention in the RYGB group with higher OT. After PSM, there were still higher rates of Clavien-Dindo Class 3a complications as well as readmission and reintervention in the RYGB subgroup with prolonged OT.

CONCLUSION

In both SG and RYGB, longer OT was associated with increased rates of complications as well as readmission, reoperation, and reintervention. Surgeons should be cognizant of the increased rates of complications when operative times are longer.

Duodenal switch without versus with laparoscopic cholecystectomy: a perioperative risk comparative analysis of the MBSAQIP database (2015-2019)

BACKGROUND

The results of concurrent cholecystectomy with Roux-en Y gastric bypass and sleeve gastrectomy have been well elucidated. Large-scale data on the outcomes of concomitant cholecystectomy during biliopancreatic diversion with duodenal switch (BPD-DS) are still lacking. Our study aimed to explore whether simultaneous cholecystectomy with BPD-DS alters the 30-day postoperative outcomes.

METHODS

We conducted a retrospective analysis of the MBSAQIP database between 2015 and 2019. Propensity-score matching (PSM) in BPD-DS with cholecystectomy (Group 1) and BPD-DS without cholecystectomy (Group 2) cohorts was performed (PSM ratio 1:2). The two groups were matched for a total of 21 baseline variables including age, gender, BMI, ASA class, and other medical comorbidities and conditions. The 30-day postoperative morbidity, mortality, reoperation, reintervention, and readmissions were obtained.

RESULTS

Initially, 568 patients in Group 1 and 5079 in Group 2 were identified. After performing PSM, 564 and 1128 patients respectively were compared. The BPD-DS with cholecystectomy group reported a higher rate of reoperation and reintervention compared to BPD-DS alone (3.9% versus 2.4% and 3.2% versus 2%, respectively), even though it did not reach statistical significance. The intervention time was significantly higher in Group 1 compared to Group 2 (192.4 ± 77.6 versus 126.4 ± 61.4 min). Clavien-Dindo complications (1-5) were similar between these two PSM cohorts.

CONCLUSION

Concomitant cholecystectomy during BPD-DS increases operative times but does not affect the other outcomes. Based on our results, the decision of cholecystectomy at the time of BPD-DS should be left to the surgeon's judgment.

Single-anastomosis duodenoileal bypass with sleeve in the United States: a first comparative safety analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database

BACKGROUND

The single-anastomosis duodenoileal bypass with sleeve (SADI-S) is a relatively new bariatric procedure. In 2020, the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) started reporting outcomes for SADI-S.

OBJECTIVES

We aimed to study the perioperative safety of SADI-S and compare it with other established bariatric procedures utilizing the MBSAQIP database.

SETTING

Academic hospital, United States.

METHODS

The 2020 MBSAQIP Participant Use File was used to evaluate SADI-S outcomes. We included SADI-S primary cases and excluded revisions and concurrent operations. A 5:1 propensity matched analysis (PMA) for 20 variables was performed to compare the outcomes of the SADI-S with the Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) and a 2:1 PMA to the biliopancreatic diversion with duodenal switch (BPD/DS).

RESULTS

There were 255 primary SADI-S reported in 2020. After PMA, the only significant complications between the RYGB and SADI-S cohorts were Clavien-Dindo grade IVa and IVb (.1% and 1.4% versus 1.6% and 7.1%, respectively). SADI-S had more Clavien-Dindo grade II, IVa, and IVb complications than the SG cohort (1.3% versus 3.5%, P = .03; .2% versus 1.6%, P = 0; 1.% versus 7.1%, P = 0). When compared with BPD/DS, outcomes including readmission, reoperation, and intervention were not statistically significant.

CONCLUSION

SADI-S, in its early adoption stage, has a higher incidence of perioperative complications than RYGB and SG. It has comparable 30-day outcomes to BPD/DS.

A-117 Posterior Cortical Atrophy Case Study: Neuropsychological Assessment Remains Gold Standard Diagnostic Tool of Choice

Objective: Posterior cortical atrophy (PCA) is a rare, early onset, neurodegenerative syndrome that is characterized by impaired visuospatial/visual-constructional skills. Patients describe vague visual symptoms; however, ocular assessments are usually normal. Alzheimer's disease is the most common underlying cause of PCA; however, brain MRI is often unrevealing early in the disease. As a result, accurate diagnosis is often delayed.

Method: The patient was initially referred in 2016 for a concussion evaluation following a work-related head injury when she was 54. Initial MRI of the brain was unremarkable. Neuropsychological testing was repeated in 2019, which was the first diagnostic test to establish a diagnosis of PCA. Subsequently, MRI of the brain with volumetric analysis showed total hippocampal volume to be at the 99th percentile and no pattern of cerebral volume loss to suggest a specific diagnosis. However, CSF biomarker assays were consistent with a diagnosis of Alzheimer’s disease.

Results: The patient’s initial cognitive profile in 2016 reflected mild cognitive impairment, multidomain type with severely impaired visual-constructional skills, which were unrelated to her concussion. Neuropsychological testing was repeated in 2019, which showed interval progressive cognitive and functional decline. Profound visual-constructional impairments were again noted (see image), and she met criteria for PCA. Neuropsychological testing was repeated in 2021 and showed progression to moderate dementia with features of Gerstmann's syndrome.

Conclusions: In spite of sophisticated neuroimaging techniques and increasing access to CSF biomarker analysis, neuropsychological assessment remains the gold standard diagnostic tool of choice for neurologists faced with rare dementia syndromes, such as PCA. See patient video at: https://youtu.be/9HdAKSL5alg

Collapse

Human macrophage polarization in the response to Mycobacterium leprae genomic DNA

•

The established thinking is that host response, rather than M. leprae strain variation, is the reason for the broad variation of symptoms in the leprosy disease spectrum

•

Recent discoveries suggest that macrophage polarization also plays a significant role in the spectrum of leprosy disease but to what degree it contributes is not fully established.

•

Utilizing DNA from three different strains of M. leprae DNA to stimulate human macrophages under three polarization conditions we observed, that the transcriptome upon stimulation with DNA from M. leprae strain Thai-53 was larger compared to strains NHDP and Br4923, independent of the macrophage polarization condition.

•

We also found that macrophage polarization affects the responses to M. leprae DNA, with up-regulation of numerous interferon stimulated genes.

•

These findings provide a deeper understanding of the role of macrophage polarization in the recognition of M. leprae DNA, with the potential to improve leprosy treatment strategies.

Infection with Mycobacterium leprae, the causative organism of leprosy, is still endemic in numerous parts of the world including the southwestern United States. The broad variation of symptoms in the leprosy disease spectrum range from the milder tuberculoid leprosy (paucibacillary) to the more severe and disfiguring lepromatous leprosy (multibacillary). The established thinking in the health community is that host response, rather than M. leprae strain variation, is the reason for the range of disease severity. More recent discoveries suggest that macrophage polarization also plays a significant role in the spectrum of leprosy disease but to what degree it contributes is not fully established. In this study, we aimed to analyze if different strains of M. leprae elicit different transcription responses in human macrophages, and to examine the role of macrophage polarization in these responses.

Genomic DNA from three different strains of M. leprae DNA (Strains NHDP, Br4923, and Thai-53) were used to stimulate human macrophages under three polarization conditions (M1, M1-activated, and M2).

Transcriptome analysis revealed a large number of differentially expressed (DE) genes upon stimulation with DNA from M. leprae strain Thai-53 compared to strains NHDP and Br4923, independent of the macrophage polarization condition. We also found that macrophage polarization affects the responses to M. leprae DNA, with up-regulation of numerous interferon stimulated genes.

These findings provide a deeper understanding of the role of macrophage polarization in the recognition of M. leprae DNA, with the potential to improve leprosy treatment strategies.

Constraints on Lightly Ionizing Particles from CDMSlite

The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) achieved efficient detection of very small recoil energies in its germanium target, resulting in sensitivity to lightly ionizing particles (LIPs) in a previously unexplored region of charge, mass, and velocity parameter space. We report first direct-detection limits calculated using the optimum interval method on the vertical intensity of cosmogenically produced LIPs with an electric charge smaller than e/(3×10^{5}), as well as the strongest limits for charge ≤e/160, with a minimum vertical intensity of 1.36×10^{-7}  cm^{-2} s^{-1} sr^{-1} at charge e/160. These results apply over a wide range of LIP masses (5  MeV/c^{2} to 100  TeV/c^{2}) and cover a wide range of βγ values (0.1-10^{6}), thus excluding nonrelativistic LIPs with βγ as small as 0.1 for the first time.

Light Dark Matter Search with a High-Resolution Athermal Phonon Detector Operated above Ground

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst)  eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140  MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

Intraoperative Airway Management Considerations for Adult Patients Presenting With Tracheostomy: A Narrative Review

Tracheotomy is a surgical procedure through which a tracheostomy, an opening into the trachea, is created. Indications for tracheostomy include facilitation of airway management during prolonged mechanical ventilation, treatment of acute upper airway obstruction when tracheal intubation is unfeasible, management of chronic upper airway obstructive conditions, and planned airway management for major head and neck surgery. Patients who have a recent or long-term tracheostomy may present for a variety of surgical or diagnostic procedures performed under general anesthesia or sedation/analgesia. Airway management of these patients can be challenging and should be planned ahead of time. Anesthesia personnel should be familiar with the different components of cuffed and uncuffed tracheostomy devices and their connectivity to the anesthesia circuits. An appropriate airway management plan should take into account the indication of the tracheostomy, the maturity status of the stoma, the type and size of tracheostomy tube, the expected patient positioning, and presence of patient's concurrent health conditions. Management of the patient with a T-tube is highlighted. Importantly, there is a need for multidisciplinary care involving anesthesiologists, surgical specialists, and perioperative nurses. The aim of this narrative review is to discuss the anesthesia care of patients with a tracheostomy. Key aspects on relevant tracheal anatomy, tracheostomy tubes/devices, alternatives of airway management, and possible complications related to tracheostomy are summarized with a recommendation for an algorithm to manage intraoperative tracheostomy tube dislodgement.

In pursuit of the unicorn

This short review was prompted by The Physiological Society's recent online symposium on variability. It does not deal with a specific methodology, but rather with the myth that certain environmentally-induced clinical conditions can be identified, quantified, simplified and monitored with a single methodology. Although this might be possible with some clinical conditions, others resist the prevailing reductionist approach of minimizing rather than exploring variation in pathogenesis and pathology, and will not be understood fully until the variation in cause and effect are embraced. This is likely to require comprehensive methodologies and collaboration.

A Real-World Evaluation of the Long-Term Safety and Efficacy of Infliximab in the Treatment Moderate-to-Severe Psoriasis

Introduction

Psoriasis is a chronic immune-mediated inflammatory skin disease that occurs in 2.5–3.5% of the general population. Infliximab (INF), a TNF-α inhibitor biologic agent, is a long-standing efficacious treatment for psoriasis; however, not all patients sustain a long-term response (LTR) because of a number of factors including antibody production. There is a paucity of studies assessing infliximab efficacy over a period ≥ 5 years.

Methods

A retrospective cohort chart review of our clinic patients who had undergone ≥ 5 years of treatment with infliximab for chronic plaque psoriasis was performed. The following variables were recorded and analyzed with the Fisher exact test: age, sex, body mass index ([BMI]; normal weight [NW], overweight [OW], obese [OB]), changes in infliximab strength (dose or frequency), concomitant systemic therapy, and side effects. Clinical improvement was assessed by comparing the total body surface area (tBSA) affected by psoriasis before and after treatment.

Results

There was a significant difference in likelihood of achieving LTR between the NW, OW and OB groups (p = 0.044). Non-normal-weight patients (OW + OB) were significantly more likely to achieve and sustain LTR than NW patients (OR 9.07, p = 0.020). There were no other significant associations for the other evaluated variables.

Limitations

Patients who began treatment with infliximab before 2009 (prior to the use of the clinic’s electronic medical record) were excluded. The Psoriasis Area and Severity Index (PASI) was not available for this study.

Conclusion

Surprisingly, patients who are overweight or obese are more likely to obtain long-term clinical benefit in their psoriasis symptoms with infliximab therapy than patients who are normal weight.

Electronic supplementary material

The online version of this article (10.1007/s13555-020-00436-1) contains supplementary material, which is available to authorized users.

Estimated health impacts from maritime transport in the Mediterranean region and benefits from the use of cleaner fuels

Ship traffic emissions degrade air quality in coastal areas and contribute to climate impacts globally. The estimated health burden of exposure to shipping emissions in coastal areas may inform policy makers as they seek to reduce exposure and associated potential health impacts. This work estimates the PM2.5-attributable impacts in the form of premature mortality and cardiovascular and respiratory hospital admissions, from long-term exposure to shipping emissions. Health impact assessment (HIA) was performed in 8 Mediterranean coastal cities, using a baseline conditions from the literature and a policy case accounting for the MARPOL Annex VI rules requiring cleaner fuels in 2020. Input data were (a) shipping contributions to ambient PM2.5 concentrations based on receptor modelling studies found in the literature, (b) population and health incidence data from national statistical registries, and (c) geographically-relevant concentration-response functions from the literature. Long-term exposure to ship-sourced PM2.5 accounted for 430 (95% CI: 220-650) premature deaths per year, in the 8 cities, distributed between groups of cities: Barcelona and Athens, with >100 premature deaths/year, and Nicosia, Brindisi, Genoa, Venice, Msida and Melilla, with tens of premature deaths/year. The more stringent standards in 2020 would reduce the number of PM2.5-attributable premature deaths by 15% on average. HIA provided a comparative assessment of the health burden of shipping emissions across Mediterranean coastal cities, which may provide decision support for urban planning with a special focus on harbour areas, and in view of the reduction in sulphur content of marine fuels due to MARPOL Annex VI in 2020.

The lung microbiome, vitamin D, and the tuberculous granuloma: A balance triangle

Mycobacterium tuberculosis (Mtb) has the extraordinary ability to persist for decades within granulomas in the human host. These histopathological structures involved in both protection and pathogenesis, are subject to various influences from the host systemically and through micro-niche environments. Despite the fact that vitamin D (VD) has a key role in macrophage activation and mycobacterial clearance in the early stages of Mtb infection, the overall role of VD in granuloma maintenance or functionality has been scarcely studied. VD deficiency has long time been known to influence on gut microbiota composition, and recent studies have shown that it can also impact on respiratory microbiome. The human microbiota plays an important role in pathogen colonization resistance, and it has been proposed to play a potential role in TB pathogenesis. In this article, we have reviewed current knowledge on the interaction between VD, the lung microbiome and TB, and propose mechanisms by which the tuberculous granuloma's outcome could be modulated by these two factors. The determinants of the final fate of lung granulomas are still unclear, and deciphering the underlying drivers of Mtb infection outcome within those structures is of critical importance.

Sleeve gastrectomy in obese Wistar rats improves diastolic function and promotes cardiac recovery independent of weight loss

BACKGROUND

Heart failure with preserved ejection fraction is the most common cause of heart failure and is characterized by impaired diastolic relaxation. Bariatric surgery significantly improves diastolic relaxation, but a mechanism beyond weight loss remains unknown.

OBJECTIVES

We tested the hypothesis that a sleeve gastrectomy (SG) will improve diastolic dysfunction independent of weight loss due to postoperative alterations in the enterocardiac axis.

SETTING

University research laboratory.

METHODS

Male Wistar rats were fed a high-fat diet (HFD) or low-fat diet (LFD) for 10 weeks and then divided into SG-HFD, pair-fed sham HFD, ad-lib sham HFD, or ad-lib sham LFD groups (n = 9-14 per group). At least 2 months postoperatively, cardiac function, meal tolerance, glucose tolerance, and cardiac gene expression were compared between groups.

RESULTS

Only the SG cohort showed significant improvements in postoperative diastolic relaxation (isovolumetric relaxation time pre-SG: 14.7 ± 2.3 msec, post-SG: 11.2 ± 1.8 msec, P < .001). SG significantly increased active glucagon-like peptide-1 (P = .03). Compared to pair-fed sham HFD rats, SG-HFD rats had significantly altered mRNA cardiac gene expression, including sarco/endoplasmic reticulum Ca2+-ATPase 2 a (SERCA2 a) (P < .001).

CONCLUSIONS

SG improves diastolic function independent of weight loss in a rat model of obesity with beneficial alterations in cardiac gene expression of multiple known targets related to cardiac failure, including SERCA2 a. These data support that a greater curve gastrectomy induces beneficial intracellular cardiac signaling for diastolic function mediated by the enterocardiac axis that is independent of weight loss. These findings could translate to offering metabolic surgery to patients with heart failure with preserved ejection fraction.

Orbital mass as first presentation of metastatic p16-positive oropharyngeal squamous cell carcinoma

We describe a case in which a 67-year-old man was diagnosed with a metastatic recurrence of p16-positive oropharyngeal squamous cell carcinoma after presenting with a medial orbital mass in the region of the nasolacrimal apparatus. A review of the literature revealed that metastasis to the orbit from any malignancy is an uncommon occurrence, and no cases of p16-positive oropharyngeal squamous cell carcinoma have previously been reported. Our case highlights the importance of maintaining a high index of suspicion during surveillance visits with such patients.

Role of vitamin A metabolism in IIH: Results from the idiopathic intracranial hypertension treatment trial

INTRODUCTION

Vitamin A and its metabolites (called retinoids) have been thought to play a role in the development of idiopathic intracranial hypertension (IIH). The IIH Treatment Trial (IIHTT) showed the efficacy of acetazolamide (ACZ) in improving visual field function, papilledema grade, quality of life and cerebrospinal fluid (CSF) pressure. We postulated that IIH patients would demonstrate elevated measures of vitamin A metabolites in the serum and CSF.

METHODS

Comprehensive measures of serum vitamin A and its metabolites were obtained from 96 IIHTT subjects, randomly assigned to treatment with ACZ or placebo, and 25 controls with similar gender, age and body mass index (BMI). These included retinol, retinol binding protein, all-trans retinoic acid (ATRA), alpha- and beta-carotenes, and beta-cryptoxanthin. The IIHTT subjects also had CSF and serum vitamin A and metabolite measurements obtained at study entry and at six months.

RESULTS

At study entry, of the vitamin A metabolites only serum ATRA was significantly different in IIHTT subjects (median 4.33nM) and controls (median 5.04nM, p=0.02). The BMI of IIHTT subjects showed mild significant negative correlations with serum ATRA, alpha- and beta-carotene, and beta-cryptoxanthin. In contrast, the control subject BMI correlated only with serum ATRA. At six months, the serum retinol, alpha-carotene, beta-carotene, and CSF retinol were increased from baseline in the ACZ treated group, but only increases in alpha-carotene (p=0.02) and CSF ATRA (p=0.04) were significantly greater in the ACZ group compared with the placebo group. No other vitamin A measures were significantly altered over the six months in either treatment group. Weight loss correlated with only with the change in serum beta-carotene (r=-0.44, p=0.006) and the change in CSF retinol (r=-0.61, p=0.02).

CONCLUSION

Vitamin A toxicity is unlikely a contributory factor in the causation of IIH. Our findings differ from those of prior reports in part because of our use of more accurate quantitative methods and measuring vitamin A metabolites in both serum and CSF. ACZ may alter retinoid metabolism in IIH patients.

Parental Concerns of Early Development in Children with Autism and Related Disorders

Parents of consecutively referred children with autism (39), Asperger syndrome (13), atypical autism (15), learning disability (20) and semantic-pragmatic disorder (14) completed a questionnaire on concerns regarding their child's development between 12 and 18 months. The early development questionnaire included scales of communication and language, social relationships and play behaviour. The autism and the learning disability groups differed significantly on most items. The diagnosis of autism was best predicted by play behaviour items and lack of referential gestures. Factor analysis within the autism group identified factors involving items from different scales, such as lack of physical contact, social communication and imitative skills. Children with the diagnosis of semantic-pragmatic disorders had relatively high rates of early difficulties in social development. Implications for the screening and detection of autism and related disorders in early life and for the training of professionals involved are discussed.

Peri-operative renal dysfunction: prevention and management

Postoperative increases in serum creatinine concentration, by amounts historically viewed as trivial, are associated with increased morbidity and mortality. Acute kidney injury is common, affecting one in five patients admitted with acute medical disease and up to four in five patients admitted to intensive care, of whom one in two have had operations. This review is focused principally on the identification of patients at risk of acute kidney injury and the prevention of injury. In the main, there are no interventions that directly treat the damaged kidney. The management of acute kidney injury is based on correction of dehydration, hypotension, and urinary tract obstruction, stopping nephrotoxic drugs, giving antibiotics for bacterial infection, and commencing renal replacement therapy if necessary.

Relieving thermal discomfort: Effects of sprayed L-menthol on perception, performance, and time trial cycling in the heat

L-menthol stimulates cutaneous thermoreceptors and induces cool sensations improving thermal comfort, but has been linked to heat storage responses; this could increase risk of heat illness during self-paced exercise in the heat. Therefore, L-menthol application could lead to a discrepancy between behavioral and autonomic thermoregulatory drivers. Eight male participants volunteered. They were familiarized and then completed two trials in hot conditions (33.5 °C, 33% relative humidity) where their t-shirt was sprayed with CONTROL-SPRAY or MENTHOL-SPRAY after 10 km (i.e., when they were hot and uncomfortable) of a 16.1-km cycling time trial (TT). Thermal perception [thermal sensation (TS) and comfort (TC)], thermal responses [rectal temperature (Trec ), skin temperature (Tskin )], perceived exertion (RPE), heart rate, pacing (power output), and TT completion time were measured. MENTHOL-SPRAY made participants feel cooler and more comfortable and resulted in lower RPE (i.e., less exertion) yet performance was unchanged [TT completion: CONTROL-SPRAY 32.4 (2.9) and MENTHOL-SPRAY 32.7 (3.0) min]. Trec rate of increase was 1.40 (0.60) and 1.45 (0.40) °C/h after CONTROL-SPRAY and MENTHOL-SPRAY application, which were not different. Spraying L-menthol toward the end of self-paced exercise in the heat improved perception, but did not alter performance and did not increase heat illness risk.

Barefoot running improves economy at high intensities and peak treadmill velocity

AIM

Barefoot running can improve running economy (RE) compared to shod running at low exercise intensities, but data is lacking for the higher intensities typical during many distance running competitions. The influence of barefoot running on the velocity at maximal oxygen uptake (vVO2max) and peak incremental treadmill test velocity (vmax) is unknown. The present study tested the hypotheses that barefoot running would improve RE, vVO2max and vmax relative to shod running.

METHODS

Using a balanced within-subject repeated measures design, eight male runners (aged 23.1±4.5 years, height 1.80±0.06 m, mass 73.8±11.5 kg, VO2max 4.08±0.39 L·min(-1)) completed a familiarization followed by one barefoot and one shod treadmill running trial, 2-14 days apart. Trial sessions consisted of a 5 minute warm-up, 5 minute rest, followed by 4×4 minute stages, at speeds corresponding to ~67, 75, 84 and 91% shod VO2max respectively, separated by a 1 minute rest. After the 4th stage treadmill speed was incremented by 0.1 km·h(-1) every 15 s until participants reached volitional exhaustion.

RESULTS

RE was improved by 4.4±7.0% across intensities in the barefoot condition (P=0.040). The improvement in RE was related to removed shoe mass (r2=0.80, P=0.003) with an intercept at 0% improvement for RE at 0.520 kg total shoe mass. Both vVO2max (by 4.5±5.0%, P=0.048) and vmax (by 3.9±4.0%, P=0.030) also improved but VO2max was unchanged (p=0.747).

CONCLUSION

Barefoot running improves RE at high exercise intensities and increases vVO2max and vmax, but further research is required to clarify the influence of very light shoe weights on RE.

Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory

Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

Spraying with 0.20% L-menthol does not enhance 5 km running performance in the heat in untrained runners

BACKGROUND

L-Menthol stimulates cutaneous thermoreceptors and induces cool sensations improving thermal comfort but has also been linked to heat storage responses. Therefore, L-Menthol application could lead to a conflict in behavioural and thermoregulatory drivers improving comfort but leading to a higher rate of deep body temperature rise; the present study examined this possibility.

METHODS

Six untrained male participants (age 21 [1] years; height 1.80 [0.07] m; mass 78.9 [6.9] kg; surface area 1.98 [0.13] m2) took part. They completed three trials in hot conditions (34 °C) where their clothing was sprayed (CONTROL-SPRAY or MENTHOL-SPRAY) or not sprayed (CONTROL) after a fixed intensity exercise period (15-minutes), which induced thermal discomfort, before completing a 5 km treadmill time trial (TT). Thermal perception (thermal sensation and comfort; TS, TC), thermal responses (aural temperature [Tau], skin temperature [Tskin]), perceived exertion (RPE), heart rate, pacing (1 km split time) and performance (TT completion time) were measured.

RESULTS

MENTHOL-SPRAY induced improvements in TS (up to 3 km of TT) and TC (up to 1 km) with Tau showing a tendency to be higher than CONTROL-SPRAY (+0.20 [0.29] °C) and CONTROL condition (0.30 [0.34] °C); this was not statistically significant and the rate of rise in Tau was linear. Tau was continuing to rise between the 4th and 5th kilometre of the TT. The other variables were unchanged. TT completion time and pace were not different: CONTROL 27.92 [1.65], CONTROL-SPRAY 28.10 [1.12], MENTHOL-SPRAY 27.53 [2.85] minutes.

CONCLUSION

Spraying L-MENTHOL prior to exercise in the heat culminated in improved perception but not altered performance.

Measurement of transient atomic displacements in thin films with picosecond and femtometer resolution

We report measurements of the transient structural response of weakly photo-excited thin films of BiFeO3, Pb(Zr,Ti)O3, and Bi and time-scales for interfacial thermal transport. Utilizing picosecond x-ray diffraction at a 1.28 MHz repetition rate with time resolution extending down to 15 ps, transient changes in the diffraction angle are recorded. These changes are associated with photo-induced lattice strains within nanolayer thin films, resolved at the part-per-million level, corresponding to a shift in the scattering angle three orders of magnitude smaller than the rocking curve width and changes in the interlayer lattice spacing of fractions of a femtometer. The combination of high brightness, repetition rate, and stability of the synchrotron, in conjunction with high time resolution, represents a novel means to probe atomic-scale, near-equilibrium dynamics.

Physiological cost and thermal envelope: a novel approach to cycle garment evaluation during a representative protocol

This study aimed to examine thermoregulation in different clothing assemblies during a representative cycling exercise protocol. Six men undertook cycling exercise simulating representative thermal exchange challenges while wearing low (LOW), intermediate (INT1 and INT2), or high (HI) amounts of clothing. Exercise was conducted at 14.5 °C, 46.8% relative humidity and included a "flat" [45 min at 35% peak power output (PPO), wind speed 8.3 m/s], "uphill" (30 min at 55% PPO, wind speed 3.6 m/s), and "downhill" (20 min at 50 W, wind speed 16.7 m/s) stage. Rectal temperature changed with the exercise stage and was independent of clothing assembly. In contrast, an "envelope" was evident for mean body temperature, resulting from differences in mean skin temperature between the LOW and HI conditions. The elevated mean body temperature in HI was associated with increased physiological "cost," in the form of increased sweat production and heart rate. Physiological cost provides a better index of clothing performance than deep body temperature in the "thermoregulatory zone," as a consequence sports clothing should attempt to optimize the balance between comfort and reduced physiological cost.

The effects of high-fat diet, branched-chainamino acids and exercise on female C57BL/6 mouse Achilles tendon biomechanical properties

Objectives

The goals of this study were: 1) to determine if high-fat diet (HFD) feeding in female mice would negatively impact biomechanical and histologic consequences on the Achilles tendon and quadriceps muscle; and 2) to investigate whether exercise and branched-chain amino acid (BCAA) supplementation would affect these parameters or attenuate any negative consequences resulting from HFD consumption.

Methods

We examined the effects of 16 weeks of 60% HFD feeding, voluntary exercise (free choice wheel running) and BCAA administration in female C57BL/6 mice. The Achilles tendons and quadriceps muscles were removed at the end of the experiment and assessed histologically and biomechanically.

Results

HFD feeding significantly decreased the Achilles tendon modulus without histological alterations. BCAA administration significantly decreased the stiffness of Achilles tendons in the exercised normal diet mice. Exercise partially ameliorated both the weight gain and glucose levels in the HFD-fed mice, led to a significant decrease in the maximum load of the Achilles tendon, and an increase in the average fibril diameter of the quadriceps femoris muscle. There were significant correlations between body weight and several biomechanical properties, demonstrating the importance of controlling obesity for maintaining healthy tendon properties.

Conclusions

In summary, this study showed a significant impact of obesity and body weight on tendon biomechanical properties with limited effects of exercise and BCAAs.

Cite this article: Bone Joint Res 2013;2:186–92.