Relationship Between Diaphragm Thickness, Thickening Fraction, Dome Excursion, and Respiratory Pressures in Healthy Subjects: An Ultrasound Study.

PURPOSE: Diaphragm ultrasonography is used to identify causes of diaphragm dysfunction. However, its correlation with pulmonary function tests, including maximal inspiratory (MIP) and expiratory pressures (MEP), remains unclear. This study investigated this relationship by measuring diaphragm thickness, thickening fraction (TF), and excursion (DE) using ultrasonography, and their relationship to MIP and MEP. It also examined the influence of age, sex, height, and BMI on these measures. METHODS: We recruited healthy Japanese volunteers and conducted pulmonary function tests and diaphragm ultrasonography in a seated position. Diaphragm ultrasonography was performed during quiet breathing (QB) and deep breathing (DB) to measure the diaphragm thickness, TF, and DE. A multivariate analysis was conducted, adjusting for age, sex, height, and BMI. RESULTS: Between March 2022 and January 2023, 109 individuals (56 males) were included from three facilities. The mean (standard deviation) MIP and MEP [cmH2O] were 72.2 (24.6) and 96.9 (35.8), respectively. Thickness [mm] at the end of expiration was 1.7 (0.4), TF [%] was 50.0 (25.9) during QB and 110.7 (44.3) during DB, and DE [cm] was 1.7 (0.6) during QB and 4.4 (1.4) during DB. Multivariate analysis revealed that only DE (DB) had a statistically significant relationship with MIP and MEP (p = 0.021, p = 0.008). Sex, age, and BMI had a statistically significant influence on relationships between DE (DB) and MIP (p = 0.008, 0.048, and < 0.001, respectively). CONCLUSION: In healthy adults, DE (DB) has a relationship with MIP and MEP. Sex, age, and BMI, but not height, are influencing factors on this relationship.

Pseudohypoglycemia: A Pitfall in Everyday Practice.

Hypoglycemia is a common clinical finding, especially in the inpatient setting. However, laboratory testing may show falsely low blood glucose levels. It is crucial for clinicians to recognize the existence of pseudohypo- glycemia and know when and how to test for it.

Diaphragm Ultrasonography: Reference Values and Influencing Factors for Thickness, Thickening Fraction, and Excursion in the Seated Position.

INTRODUCTION: Measurements of diaphragm function by ultrasonography are affected by body position, but reference values in the seated position have not been established for an Asian population. This study aimed to determine reference values for diaphragm thickness, thickening fraction, and dome excursion by ultrasonography and to investigate the effects of sex, height, and body mass index. METHODS: Diaphragm ultrasonography was performed on 109 seated Japanese volunteers with normal respiratory function who were enrolled between March 2022 and January 2023. Thickness, thickening fraction, and excursion were measured. Reference values and the measurement success rate were calculated. Multivariate analysis adjusted for sex, height, and body mass index was performed. RESULTS: The measurement success rate was better for thickness than for excursion. The mean (lower limit of normal) values on the right/left sides were as follows. During quiet breathing, thickness at end expiration(mm) was 1.7 (0.9)/1.6 (0.80), thickening fraction(%) was 50 (0.0)/52 (0.0), and excursion(cm) was 1.7 (0.5)/1.9 (0.5). During deep breathing, the thickening fraction was 111 (24)/107 (22), and the excursion was 4.4 (1.7)/4.1 (2.0). In multivariate analysis, body mass index was positively associated with thickness but not with the thickening fraction. CONCLUSION: The reference values in this study were smaller than those in previous reports from Europe. Considering that thickness is influenced by body mass index, using Western reference values in Asia, where the average body mass index is lower, might not be appropriate. The thickening fraction in deep breathing is unaffected by other items and can be used more universally.

Development of a national point-of-care ultrasound training course for physicians in Japan: A 3-year evaluation.

Purpose: Point-of-care ultrasound (POCUS) allows bedside clinicians to acquire, interpret, and integrate ultrasound images into patient care. Although the availability of POCUS training courses has increased, the educational effectiveness of these courses is unclear. Methods: From 2017 to 2019, we investigated the educational effectiveness of a standardized 2-day hands-on POCUS training course and changes in pre- and post-course exam scores in relationship to participants' (n = 571) clinical rank, years of POCUS experience, and frequency of POCUS use in clinical practice. Results: The mean pre- and post-course examination scores were 67.2 (standard deviation [SD] 12.3) and 79.7 (SD 9.7), respectively. Higher pre-course examination scores were associated with higher clinical rank, more years of POCUS experience, and more frequent POCUS use (p < 0.05). All participants showed significant changes in pre- to post-course exam scores. Though pre-course scores differed by clinical rank, POCUS experience, and frequency of POCUS use, differences in post-course scores according to participant baseline differences were non-significant. Conclusion: A standardized hands-on POCUS training course is effective for improving POCUS knowledge regardless of baseline differences in clinical rank, POCUS experience, or frequency of POCUS use. Future studies shall evaluate changes in POCUS use in clinical practice after POCUS training.

Lung Ultrasound for Pleural Line Abnormalities, Confluent B-Lines, and Consolidation: Expert Reproducibility and a Method of Standardization.

OBJECTIVES: Discrete B-lines have clear definitions, but confluent B-lines, consolidations, and pleural line abnormalities are less well defined. We proposed definitions for these and determined their reproducibility using COVID-19 patient images obtained with phased array probes. METHODS: Two raters collaborated to refine definitions, analyzing disagreements on 107 derivation scans from 10 patients. Refined definitions were used by those raters and an independent rater on 1260 validation scans from 105 patients. Reliability was evaluated using intraclass correlation coefficients (ICC) or Cohen's kappa. RESULTS: The agreement was excellent between collaborating raters for B-line abnormalities, ICC = 0.97 (95% confidence interval [CI] 0.97-0.98) and pleural line to consolidation abnormalities, ICC = 0.90 (95% CI 0.87-0.92). The independent rater's agreement for B-line abnormalities was excellent, ICC = 0.97 (95% CI 0.96-0.97) and for pleural line to consolidation was good, ICC = 0.88 (95% CI 0.84-0.91). Agreement just on pleural line abnormalities was weak (collaborators, κ = 0.54, 95% CI 0.48-0.60; independent, κ = 0.54, 95% CI 0.49-0.59). CONCLUSION: With proposed definitions or via collaboration, overall agreement on confluent B-lines and pleural line to consolidation abnormalities was robust. Pleural line abnormality agreement itself was persistently weak and caution should be used interpreting pleural line abnormalities with only a phased array probe.

Point-of-Care Lung Ultrasound for COVID-19: Findings and Prognostic Implications From 105 Consecutive Patients.

BACKGROUND: The prognostic value of point-of-care lung ultrasound has not been evaluated in a large cohort of patients with COVID-19 admitted to general medicine ward in the United States. The aim of this study was to describe lung ultrasound findings and their prognostic value in patients with COVID-19 admitted to internal medicine ward. METHOD: This prospective observational study consecutively enrolled 105 hospitalized participants with COVID-19 at 2 tertiary care centers. Ultrasound was performed in 12 lung zones within 24 hours of admission. Findings were assessed relative to 4 outcomes: intensive care unit (ICU) need, need for intensive respiratory support, length of stay, and death. RESULTS: We detected abnormalities in 92% (97/105) of participants. The common findings were confluent B-lines (92%), non-homogenous pleural lines (78%), and consolidations (54%). Large confluent B-lines, consolidations, bilateral involvement, and any abnormality in ≥ 6 areas were associated with a longer hospitalization and need for intensive respiratory support. Large confluent B-lines and bilateral involvement were also associated with ICU stay. A total lung ultrasound score <5 had a negative predictive value of 100% for the need of intensive respiratory support. A higher total lung ultrasound score was associated with ICU need (median total 18 in the ICU group vs. 11 non-ICU, p = 0.004), a hospitalization ≥ 9d (15 vs 10, p = 0.016) and need for intensive respiratory support (18 vs. 8.5, P < 0.001). CONCLUSIONS: Most patients hospitalized with COVID-19 had lung ultrasound abnormalities on admission and a higher lung ultrasound score was associated with worse clinical outcomes except death. A low total lung ultrasound score (<5) had a negative predictive value of 100% for the need of intensive respiratory support. Point-of-care ultrasound can aid in the risk stratification for patients with COVID-19 admitted to general wards.

Ketoacidosis associated with ketogenic diet in a non-diabetic lactating woman.

A 37-year-old woman who had 8 weeks post partum, breast feeding and on a low carbohydrate and high protein (ketogenic) diet, was admitted to the hospital with acute onset of nausea, vomiting and abdominal pain of 1-day duration. On admission, she was found to have high anion gap metabolic acidosis, elevated beta-hydroxybutyric acid level, normal glucose level and evidence of ketoacidosis. She was treated with lactated Ringer solution, along with dextrose 5% solution with the resolution of symptoms and metabolic derangement.

Point-of-Care Lung Ultrasound Findings in Patients with COVID-19 Pneumonia.

Patients with novel coronavirus disease (COVID-19) typically present with bilateral multilobar ground-glass opacification with a peripheral distribution. The utility of point-of-care ultrasound has been suggested, but detailed descriptions of lung ultrasound findings are not available. We evaluated lung ultrasound findings in 10 patients admitted to the internal medicine ward with COVID-19. All of the patients had characteristic glass rockets with or without the Birolleau variant (white lung). Thick irregular pleural lines and confluent B lines were also present in all of the patients. Five of the 10 patients had small subpleural consolidations. Point-of-care lung ultrasound has multiple advantages, including lack of radiation exposure and repeatability. Also, lung ultrasound has been shown to be more sensitive than a chest radiograph in detecting alveolar-interstitial syndrome. The utilization of lung ultrasound may also reduce exposure of healthcare workers to severe acute respiratory syndrome-coronavirus-2 and may mitigate the shortage of personal protective equipment. Further studies are needed to evaluate the utility of lung ultrasound in the diagnosis and management of COVID-19.

Skills acquisition for novice learners after a point-of-care ultrasound course: does clinical rank matter?

BACKGROUND: Few studies have compared the effectiveness of brief training courses on point-of-care ultrasound (POCUS) skill acquisition of novice attending physicians vs. trainees. The purpose of this study was to evaluate the change in POCUS image interpretation skills and confidence of novice attending physicians vs. trainees after a 1-day POCUS training course. METHODS: A 1-day POCUS training course was held in March 2017 in Japan. A standardized training curriculum was developed that included online education, live lectures, and hands-on training. The pre-course assessment tools included a written examination to evaluate baseline knowledge and image interpretation skills, and a physician survey to assess confidence in performing specific ultrasound applications. The same assessment tools were administered post-course, along with a course evaluation. All learners were novices and were categorized as trainees or attending physicians. Data were analyzed using two-way analysis of variance. RESULTS: In total, 60 learners attended the course, and 51 learners (85%) completed all tests and surveys. The 51 novice learners included 29 trainees (4 medical students, 9 PGY 1-2 residents, 16 PGY 3-5 residents) and 22 attending physicians (6 PGY 6-10 physicians, and 16 physicians PGY 11 and higher). The mean pre- and post-course test scores of novice trainees improved from 65.5 to 83.9% while novice attending physicians improved from 66.7 to 81.5% (p < 0.001). The post-course physician confidence scores in using ultrasound significantly increased in all skill categories for both groups. Both trainees and attending physicians demonstrated similar improvement in their post-course test scores and confidence with no statistically significant differences between the groups. The course evaluation scores for overall satisfaction and satisfaction with faculty members' teaching skills were 4.5 and 4.6 on a 5-point scale, respectively. CONCLUSIONS: Both novice trainees and attending physicians showed similar improvement in point-of-care ultrasound image interpretation skills and confidence after a brief training course. Although separate training courses have traditionally been developed for attending physicians and trainees, novice learners of point-of-care ultrasound may acquire skills at similar rates, regardless of their ranking as an attending physician or trainee. Future studies are needed to compare the effectiveness of short training courses on image acquisition skills and determine the ideal course design.

Acute COPD exacerbation presenting with pronounced intrabullous haemorrhage and haemoptysis.

A 54-year-old man with history of chronic obstructive pulmonary disease (COPD) presented with subacute onset of chest pain, shortness of breath, productive cough with haemoptysis and night sweats. There were no fever or recent weight loss reported. The chest radiograph showed right upper lobe bullae with adjacent opacification and an emphysematous lung. Due to worsening haemoptysis and persistent chest pain, CT of the chest with contrast was performed, which revealed moderate to severe emphysema and numerous blood-filled bullae. Cardiac work-up for chest pain was negative for myocardial ischaemia and for aortic dissection. Further infectious work-ups for mycobacterial and invasive fungal infection were negative. The patient was treated for acute COPD exacerbation and responded well to the antibiotics with the resolution of haemoptysis. Follow-up CT of the chest revealed the gradual resolution of the haemorrhage, while the patient remained asymptomatic.

Assessing Diaphragm Function in Chest Wall and Neuromuscular Diseases.

Diaphragm dysfunction is defined as the partial or complete loss of diaphragm muscle contractility. However, because the diaphragm is one of only a few skeletal muscles that is not amenable to direct examination, the tools available for the clinician to assess diaphragm function have been limited. Traditionally, measures of lung volume, inspiratory muscle strength, and radiographic techniques such as fluoroscopy have provided the major method to assess diaphragm function. Measurement of transdiaphragmatic pressure provides the most direct means of evaluating the diaphragm, but this technique is not readily available to clinicians. Diaprhragm ultrasonography is new method that allows for direct examination of the diaphragm.

Disorders of the Diaphragm.

Pathologic processes that involve the central nervous system, phrenic nerve, neuromuscular junction, and skeletal muscle can impair diaphragm function. When these processes are of sufficient severity to cause diaphragm dysfunction, respiratory failure may be a consequence. This article reviews basic diaphragm anatomy and physiology and then discusses diagnostic and therapeutic approaches to disorders that result in unilateral or bilateral diaphragm dysfunction. This discussion provides a context in which disorders of the diaphragm and their implications on respiratory function can be better appreciated.

Metformin-Associated Lactic Acidosis: A Case Report.

A 54-year-old woman with type 2 diabetes mellitus, hypertension, and peripheral vascular disease developed life-threatening lactic acidosis during treatment with metformin for type 2 diabetes. The woman received metformin at 1000 mg orally twice a day for type 2 diabetes. She presented to our emergency department with a 3-day history of severe watery diarrhea, nausea, and vomiting. Her grandson whom she cared for had gastroenteritis several days prior to the onset of her symptoms. She was confused and hypotensive with a blood pressure of 70/39 mmHg. Her initial laboratory findings were remarkable with an arterial blood gas pH 6.57, HCO[Formula: see text] 2 mEq/L, anion gap 30 mmol/L, and lactate 16.3 mmol/L. She was diagnosed with severe lactic acidosis. Metformin was discontinued. Upon arrival in the emergency department, she became unresponsive and experienced a pulseless electrical activity cardiac arrest. After resuscitation, her severe acidemia persisted despite aggressive intervention with volume resuscitation and vasopressors, leading to the initiation of renal replacement therapy. After multiple dialysis treatments, her severe acidemia resolved. Serum metformin concentration from presentation ultimately returned to 42 mcg/mL (therapeutic concentration: 1-2 mcg/mL). She was discharged from the hospital on day 15 without any neurologic complications. A Naranjo assessment score of 8 was obtained, indicating a probable relationship between the patient's lactic acidosis and her use of the suspect drug.

Musical Instrument-Associated Health Issues and Their Management.

Playing musical instruments can bring joy to people, but can also cause a wide variety of health issues that range from mild disorders to potentially fatal conditions. Although sports medicine is an established medical subspecialty, relatively few studies have investigated the health issues associated with musical instruments. Here we present an overview of these health issues. These include infections due to microorganisms, allergic reactions, as well as mechanical injuries from sustained high pressures within the oral, mediastinal, thoracic, and abdominal cavities. For example, wind instruments can potentially harbor thousands of pathogenic organisms. If several players share the same instrument, these instruments present potential hazards in the spread of infections. A fatal case of hypersensitivity pneumonitis in a bagpiper is particularly noteworthy. Similarly, a case of gastrointestinal anthrax in an animal-hide drummer is a reminder of this rare but highly fatal disease. Although not fatal, hearing-related disorders, neuromuscular issues, musculoskeletal problems, and contact dermatitis are also very common among instrumentalists. This review aims to illuminate these under-recognized health issues by highlighting both the common conditions and the rare but fatal cases.

ERRATUM: Unexpected Serious Cardiac Arrhythmias in the Setting of Loperamide Abuse.

Loperamide (Imodium) is a non-prescription opioid receptor agonist available over-the-counter for the treatment of diarrhea. When ingested in excessive doses, loperamide can penetrate the blood-brain barrier and is reported to produce euphoria, central nervous system and respiratory depression, and cardiotoxicity. There is an emerging trend in its use among drug abusers for its euphoric effects or for self-treatment of opioid withdrawal. We report a case of ventricular dysrhythmias associated with loperamide abuse in a 28-year-old man who substituted loperamide for the opioids that he used to abuse. [Full article available at http://rimed.org/rimedicaljournal-2017-04.asp, free with no login].

Unexpected Serious Cardiac Arrhythmias in the Setting of Loperamide Abuse.

Loperamide (Imodium) is a non-prescription opioid receptor agonist available over-the-counter for the treatment of diarrhea. When ingested in excessive doses, loperamide can penetrate the blood-brain barrier and is reported to produce euphoria, central nervous system and respiratory depression, and cardiotoxicity. There is an emerging trend in its use among drug abusers for its euphoric effects or for self-treatment of opioid withdrawal. We report a case of ventricular dysrhythmias associated with loperamide abuse in a 28-year-old man who substituted loperamide for the opioids that he used to abuse. [Full article available at http://rimed.org/rimedicaljournal-2017-04.asp].

Right in Front of Our Eyes: Evolution of Streptococcal Toxic Shock Syndrome with Ischemic Optic Neuropathy.

INTRODUCTION: Toxic shock syndrome occurs from dysregulation of host inflammatory responses. Toxin- producing strains of Group A streptococcus cause TSS. Ischemic optic neuropathy rarely complicates septic shock. We present a rare case of streptococcal pharyngitis complicated by septic arthritis and TSS with reversible blindness due to non-arteritic ischemic optic neuropathy. CASE: A 28-year-old man drove to our ED with exudative pharyngitis. A rapid streptococcal test was positive. While awaiting oral penicillin he became hypotensive refractory to IV fluids and developed knee effusion. The patient noted progressive dimming of his vision. Arthrocentesis yielded GAS. ICU course was complicated by ARDS but after 2 weeks the patient was weaned off vasopressors and the ventilator. He regained his vision and had no neurological sequelae. The patient's GAS isolate was M protein gene (emm) type 1 and T type 1. He was followed in the IM clinic for 9 months post discharge with complete resolution of symptoms. CONCLUSION: The rapidity of the development of shock is attributed to streptococcal exotoxins acting as superantigens. GAS type M1 is commonly associated with severe shock in TSS. The severe shock was the likely cause of his ischemic optic neuropathy. Early recognition and aggressive management of TSS are crucial to clinical outcome. [Full article available at http://rimed.org/rimedicaljournal-2016-12.asp].

Influenza Induced Cardiomyopathy: An Unusual Cause of Hypoxemia.

Influenza has considerable burden on public health funds. The complications of influenza can be devastating. We present a case of a 42-year-old woman with history of asthma who presented to the emergency room in winter with shortness of breath and general malaise and was found to be in hypoxemic respiratory failure. She was diagnosed with influenza and workup revealed severely depressed systolic cardiac function (ejection fraction of 25%). She was treated with oseltamivir and diuresis and regained cardiac function within a week. We review the pathophysiology and management of influenza induced cardiomyopathy.

Hypertriglyceridemia-Induced Pancreatitis: A Decade of Experience in a Community-Based Teaching Hospital.

INTRODUCTION: Hypertriglyceridemia is the third most common cause of acute pancreatitis. The current evidence on the management of hypertriglyceridemia-induced pancreatitis (HTGP) is mainly derived from case series. It has been suggested that insulin, and plasmapheresis have a role in the management of acute HTGP. We present a retrospective review of patients seen at a community-teaching hospital between 2005 and 2015. RESULTS: Out of the 549 admissions for acute pancreatitis, fourteen patients met our inclusion criteria. The mean age of presentation was 39± 8 years and there was a predominance of men (57%). More than two-thirds of the patients were admitted to the intensive care unit. The majority of the patients were treated with insulin drip (n=8), and the rest by subcutaneous insulin (n=3) and insulin drip + plasmapheresis (n=3). In the insulin drip group we noted a gradual decrease of the admission serum triglycerides by 50.6 ±16.0 % at 24 hours, 65.9±16.9% at 48 hours, and then 85.2± 7.1% at discharge. Serum triglycerides decreased by 79.8% and 92.6%, at discharge in the subcutaneous insulin and insulin + plasmapheresis cohorts, respectively. The insulin + plasmapheresis cohort stayed in the hospital longer (20.7±3.1 days) compared to the insulin drip (10.3±5.4 days) and subcutaneous insulin (5.7 ± 1.2 days) cohorts. CONCLUSION: Our study strengthens the evidence for using insulin (infusion or subcutaneous) with or without plasmapheresis in the treatment of hypertriglycerimia-induced pancreatitis.