Effects of Changes in Inspiratory Time on Inspiratory Flowrate and Airway Pressure during Cardiopulmonary Resuscitation: A Manikin-Based Study / 고신대학교의과대학학술지

Objectives@#Given that cardiopulmonary resuscitation (CPR) is an aerosol-generating procedure, it is necessary to use a mechanical ventilator and reduce the number of providers involved in resuscitation for in-hospital cardiac arrest in coronavirus disease (COVID-19) patients or suspected COVID-19 patients. However, no study assessed the effect of changes in inspiratory time on flowrate and airway pressure during CPR. We herein aimed to determine changes in these parameters during CPR and identify appropriate ventilator management for adults during CPR. @*Methods@#We measured changes in tidal volume (Vt), peak inspiratory flow rate (PIFR), peak airway pressure (Ppeak), mean airway pressure (Pmean) according to changes in inspiratory time (0.75 s, 1.0 s and 1.5 s) with or without CPR. Vt of 500 mL was supplied (flowrate: 10 times/min) using a mechanical ventilator. Chest compressions were maintained at constant compression depth (53 ± 2 mm) and speed (102 ± 2/min) using a mechanical chest compression device. @*Results@#Median levels of respiratory physiological parameters during CPR were significantly different according to the inspiratory time (0.75 s vs. 1.5 s): PIFR (80.8 [73.3 – 87.325] vs. 70.5 [67 – 72.4] L/min, P < 0.001), Ppeak (54 [48 – 59] vs. 47 [45 – 49] cmH2O, P < 0.001), and Pmean (3.9 [3.6 – 4.1] vs. 5.7 [5.6 – 5.8] cmH2O, P < 0.001). @*Conclusions@#Changes in PIFR, Ppeak, and Pmean were associated with inspiratory time. PIFR and Ppeak values tended to decrease with increase in inspiratory time, while Pmean showed a contrasting trend. Increased inspiratory time in low-compliance cardiac arrest patients will help in reducing lung injury during adult CPR.

Association between a Multidisciplinary Team Approach and Clinical Outcomes in Patients Undergoing Extracorporeal Cardiopulmonary Resuscitation in the Emergency Department

Background and Objectives@#Despite recent improvements in advanced life support, the overall survival rate after cardiac arrest remains low. We aimed to examine the association of a multidisciplinary team approach with clinical outcomes in patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) in the emergency department (ED). @*Methods@#This retrospective, single-center, observational study included 125 patients who underwent ECPR in the ED between May 2004–December 2018. In January 2014, our institution implemented a multidisciplinary extracorporeal membrane oxygenation (ECMO) team. Eligible patients were classified into pre-ECMO-team (n=65) and post-ECMO-team (n=60) groups. The primary outcome was in-hospital mortality. @*Results@#In-hospital mortality (72.3% vs. 58.3%, p=0.102) and poor neurological outcomes (78.5% vs. 68.3%, p=0.283) did not differ significantly between the pre- and post-ECMOteam groups. However, among the 60 patients who experienced in-hospital cardiac arrest,in-hospital mortality (75.8% vs. 40.7%, p=0.006) and poor neurological outcomes (78.8% vs. 48.1%, p=0.015) significantly decreased after the multidisciplinary team formation.Multivariable logistic regression analysis showed that the multidisciplinary team approach (adjusted odds ratio, 0.20; 95% confidence interval, 0.07–0.61; p=0.005) was an independent prognostic factor for in-hospital mortality in in-hospital cardiac arrest patients. @*Conclusions@#A multidisciplinary team approach was associated with improved clinical outcomes in in-hospital cardiac arrest patients undergoing ECPR in the ED. These findings may help in improving the selection criteria for ECPR in the ED. Further studies to overcome the study limitations may help improving the outcomes of out-of-hospital cardiac arrest patients.

The Characteristics of Elderly Individuals Who Attempted Suicide by Poisoning: a Nationwide Crosssectional Study in Korea

Background@#Suicide among the elderly is a public health concern, as life expectancy is increasing rapidly and suicide rates increase with age. In Korea, self-poisoning is the most common method of attempted suicide. This study aimed to evaluate the characteristics of attempted suicide by self-poisoning among the elderly and to identify risk factors related to the suicide attempts. @*Methods@#A cross-sectional observational study was conducted using the Emergency Department-based Injury In-depth Surveillance database in Korea. We included all adult patients visiting the emergency department (ED) who attempted suicide by poisoning between January 2011 and December 2017 and stratified according to age: the elderly (≥ 65 years old) and the younger group. Characteristics and risk factors for attempted suicide by poisoning among the elderly were evaluated using stepwise regression analysis. @*Results@#Among 25,904 adult patients, 5,164 (19.9%) were classified as elderly. The elderly were more likely to be admitted to hospital and intensive care units, the average ED length of stay was longer, and total mortality was higher than that of the younger group. Male sex, low socioeconomic status, poor physical health, pesticide use, lower alcohol consumption, and fewer prior suicide attempts were found to be risk factors for suicide among the elderly. @*Conclusion@#Self-poisoning among the elderly is associated with poorer clinical outcomes than in younger adult patients. Suicide among the elderly is a potentially preventable public health problem, and with proper identification of the associated risk factors, appropriate multidisciplinary intervention strategies can be implemented.

Comparison of preventive effect of seat belt on traumatic brain injury by age in motor vehicle collision

Objective@#This study examined whether the preventive effects of the safety belt on traumatic brain injury (TBI) from motor vehicle collisions (MVCs) differ according to the occupants’ age. @*Methods@#This study was a retrospective, observational study. This study evaluated the crash data from 2011 to 2016 obtained from the Emergency Department-based Injury In-depth Surveillance registry. The injured occupants were categorized by age into young adults (age, 18-35 years; n=35,032), middle-aged adults (age, 36-55 years; n=34,507), and older adults (aged older than 55 years, n=21,895). The primary (TBI), secondary (intensive care unit [ICU] admission), and tertiary endpoint (mortality) were set. Multivariate logistic regression analysis was performed, and the adjusted odds ratios (aORs) of subgroups were calculated for study outcomes adjusted for any potential confounders. @*Results@#Among 91,434 patients, 61,205 used seat belts at the time of the crashes. Compared to the unbelted group, the belted group was less likely to have a TBI. A comparison of the aOR of subgroups for TBI revealed the odds ratio reduction to be the highest in young adults (aOR, 0.39; 95% confidence interval [CI], 0.32-0.47), followed by middle-aged adults (aOR, 0.39; 95% CI, 0.33-0.47) and older adults (aOR, 0.49; 95% CI, 0.42-0.56). In addition, seat belt use had a preventive effect on ICU admission and mortality at all subgroups, the effect of which decreased with age. @*Conclusion@#The protective effects of seat belts on TBI, ICU admission, and mortality from MVCs were reduced with age.

Comparison of preventive effect of seat belt on traumatic brain injury by age in motor vehicle collision

Objective@#This study examined whether the preventive effects of the safety belt on traumatic brain injury (TBI) from motor vehicle collisions (MVCs) differ according to the occupants’ age. @*Methods@#This study was a retrospective, observational study. This study evaluated the crash data from 2011 to 2016 obtained from the Emergency Department-based Injury In-depth Surveillance registry. The injured occupants were categorized by age into young adults (age, 18-35 years; n=35,032), middle-aged adults (age, 36-55 years; n=34,507), and older adults (aged older than 55 years, n=21,895). The primary (TBI), secondary (intensive care unit [ICU] admission), and tertiary endpoint (mortality) were set. Multivariate logistic regression analysis was performed, and the adjusted odds ratios (aORs) of subgroups were calculated for study outcomes adjusted for any potential confounders. @*Results@#Among 91,434 patients, 61,205 used seat belts at the time of the crashes. Compared to the unbelted group, the belted group was less likely to have a TBI. A comparison of the aOR of subgroups for TBI revealed the odds ratio reduction to be the highest in young adults (aOR, 0.39; 95% confidence interval [CI], 0.32-0.47), followed by middle-aged adults (aOR, 0.39; 95% CI, 0.33-0.47) and older adults (aOR, 0.49; 95% CI, 0.42-0.56). In addition, seat belt use had a preventive effect on ICU admission and mortality at all subgroups, the effect of which decreased with age. @*Conclusion@#The protective effects of seat belts on TBI, ICU admission, and mortality from MVCs were reduced with age.

A rare case of miliary tuberculosis accompanying perihepatitis

Perihepatic capsulitis is associated with various diseases, such as Fitz-Hugh-Curtis syndrome, systemic lupus erythematosus, perforated cholecystitis, perforated hepatic abscess, and tuberculous peritonitis. Miliary tuberculosis is present in about 2% of all reported cases of tuberculosis and is characterized by the widespread millet-like hematogenous dissemination of Mycobacterium tuberculosis. We describe a 24-year-old virgin patient presenting with right upper quadrant and costovertebral angle pain. Diffuse perihepatic capsular enhancement was observed in abdominal computed tomography scans. Chest radiography showed miliary tuberculosis, and a polymerase chain reaction hybridization assay of sputum revealed the presence of M. tuberculosis. Symptoms improved after administering anti-tuberculosis medications. This report describes a rare case of miliary tuberculosis accompanying perihepatitis.

A Preliminary Study for Effect of High Flow Oxygen through Nasal Cannula Therapy in Carbon Monoxide Poisoning

PURPOSE@#Acute carbon monoxide (CO) poisoning is one of the most common types of poisoning and a major health problem worldwide. Treatment options are limited to normobaric oxygen therapy, administered using a non-rebreather face mask or hyperbaric oxygen. Compared to conventional oxygen therapy, high-flow nasal cannula oxygen (HFNC) creates a positive pressure effect through high-flow rates. The purpose of this human pilot study is to determine the effects of HFNC on the rate of CO clearance from the blood, in patients with mild to moderate CO poisoning.@*METHODS@#CO-poisoned patients were administered 100% oxygen from HFNC (flow of 60 L/min). The fraction of COHb (fCOHb) was measured at 30-min intervals until it decreased to under 10%, and the half-life time of fCOHb (fCOHb t(1/2)) was subsequently determined.@*RESULTS@#At the time of ED arrival, a total of 10 patients had fCOHb levels ≥10%, with 4 patients ranging between 10% and 50%. The mean rate of fCOHb elimination patterns exhibits logarithmic growth curves that initially increase quickly with time (HFNC equation, Y=0.3388*X+11.67). The mean fCOHbt1/2 in the HFNC group was determined to be 48.5±12.4 minutes.@*CONCLUSION@#In patients with mild to moderate CO poisoning, oxygen delivered via high flow nasal cannula is a safe and comfortable method to treat acute CO toxicity, and is effective in reducing the COHb half-life. Our results indicate HFNC to be a promising alternative method of delivering oxygen for CO toxicity. Validating the effectiveness of this method will require larger studies with clinical outcomes.

Impact of discharge against medical advice on emergency department revisit among suicide attempters

OBJECTIVE: This study examined the clinical effects of discharge against medical advice (DAMA) on suicide reattempts and clarified the risk factors related to DAMA. METHODS: A cross-sectional observational study was conducted in the emergency department (ED) of Chungbuk National University Hospital from 2015 to 2017. The medical records of suicide attempters from the National Emergency Department Information System were reviewed. The primary outcome was the ED revisit rate. The characteristics of the patients associated with DAMA were also examined. RESULTS: Among 889 eligible suicide attempters, 328 patients (36.9%) were reported to have DAMA at least once during the study period. Patients who were discharged against medical advice were more likely to reattempt suicide compared to normal disposition patients (11.0% vs. 3.7%, adjusted odds ratio [AOR], 3.002; 95% confidence interval [CI], 1.71–5.28). The independent risk factors for DAMA were age≤60 (AOR, 1.77; 95% CI, 1.20–2.59), female (AOR, 1.45; 95% CI, 1.09–1.91), ED visit at night time (AOR, 1.41; 95% CI, 1.03–1.92), and ED discharge at night time (AOR, 1.40; 95% CI, 1.06–1.85). CONCLUSION: Patients who were discharged against medical advice revisited the ED more after suicide attempts. Public efforts will be needed for patients who are discharged against medical advice considering those risk factors.

Histopathological and Neurobehavioral Characterization in Adult Mice Exposed to Traumatic Brain Injury

PURPOSE: Traumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide. Severity of the initial insult is one of the most significant factors affecting outcome following TBI. In order to investigate the mechanisms of cellular injury and develop novel therapeutic strategies for TBI, we designed a standardized animal TBI model and evaluated histological and functional outcomes according to the degree of impact severity. METHODS: Male adult C57Bl/6 mice underwent controlled cortical impact (CCI) at varying depths of deflection (1.0-2.0 mm). We performed hematoxylin and eosin staining at 7 days after recovery from TBI. Neurobehavioral characterization after TBI was analyzed by the Barnes maze test, passive avoidance test, open field test, rotarod test, tail suspension test, and light/dark test. RESULTS: We observed a graded injury response according to the degree of deflection depths tested (diameter, 3 mm; velocity, 3 m/s; and duration, 500 ms) compared to sham controls. In the Barnes maze test, the severe TBI (2 mm depth) group showed reduced spatial memory as compared with the sham and mild TBI (1 mm depth) groups at 7 days after TBI. There was a significant difference in the results of the open field test and light/dark test among the three groups. CONCLUSION: Our findings demonstrate that the graded injury responses following TBI resulted in differential histopathological and behavioral outcomes in a mouse experimental CCI model. Thus, a model of CCI with histologic/behavioral outcome analysis may offer a reliable and convenient design for preclinical TBI research involving mice.

Stem Cell Therapy: A Prospective Treatment for Alzheimer's Disease

Alzheimer's disease (AD) without cure remains as a serious health issue in the modern society. The major neuropathological alterations in AD are characterized by chronic neuroinflammation and neuronal loss due to neurofibrillary tangles (NFTs) of abnormally hyperphosphorylated tau, plaques of β-amyloid (Aβ) and various metabolic dysfunctions. Due to the multifaceted nature of AD pathology and our limited understanding on its etiology, AD is difficult to be treated with currently available pharmaceuticals. This unmet need, however, could be met with stem cell technology that can be engineered to replace neuronal loss in AD patients. Although stem cell therapy for AD is only in its development stages, it has vast potential uses ranging from replacement therapy to disease modelling and drug development. Current progress with stem cells in animal model studies offers promising results for the new prospective treatment for AD. This review will discuss the characteristics of AD, current progress in stem cell therapy and remaining challenges and promises in its development.

Predictive Factor of Blood Pressure Lowering in Patients with Fever Using Propacetamol

PURPOSE: This study aimed to identify predictive factors for decreased blood pressure in patients prescribed with propacetamol in the emergency room using clinical and laboratory indicators of sepsis. METHODS: Among patients aged 18 years or older with a fever, who visited Chungbuk National University hospital's emergency room between July and December of 2014, 246 patients underwent intravenous infusion of propacetamol to control body temperature. Of these, 112 patients fulfilled all study requirements. Patients whose systolic or diastolic blood pressure dropped below 90 mmHg or 60 mmHg, respectively, were included in the blood pressure decline group. Additional inclusion criteria were a decline in systolic blood pressure of more than 30-mmHg and thereby treated with fluids or inotropics after intravenous infusion of propacetamol. Remaining patients were included in the blood pressure maintenance group. The relationship of each factor between the two groups was then investigated. RESULTS: Twenty-nine patients (25.9%) showed a significant decrease in blood pressure, and among many factors, high-sensitivity C-reactive protein (hs-CRP) (cut off value, 11.86; sensitivity, 72.4%; specificity, 69.9%; area under curve [AUC], 0.698) and procalcitonin (cut off value, 0.67; sensitivity, 75.9%; specificity, 60.2%; AUC, 0.667) levels showed a statistically significant effect. Of the 29 patients with a decrease in blood pressure, 10 patients received fluids and inotropics; procalcitonin in particular showed a significant effect. CONCLUSION: When propacetamol is administered to patients at the emergency room, and if hs-CRP or procalcitonin levels are high, there is an increased risk of a decrease in blood pressure. In particular, if procalcitonin levels are high, aggressive treatment is required, such as administration of inotropics in addition to fluids.

Usefulness of Immediate W-plasty in the Emergency Department for Minimizing Scar Formation: Results from a Short-term Follow-up

PURPOSE: Facial scars are a main complaint of patients who had undergone suture in the emergency department. Therefore, effective techniques for minimizing scar formation are required. W-plasty, a widely used method of scar correction, has been performed to change the scar direction or divide it into multiple segmented scars. This method can be applied in the initial stage of wound repair in the emergency department. The aim of this study was to investigate the effectiveness of direct application of W-plasty to the wound in simultaneously accomplishing the aforementioned objectives. METHODS: This was a prospective study, from June 2012 to June 2014. Either simple debridement or W-plasty for facial laceration was performed in 31 patients. In patients in the simple debridement group, the excision was made along the laceration margin. In patients in the W-plasty group, the excision was made within the W-form predesigned margin of the laceration. The prognosis was evaluated using the Stony Brook scar evaluation scale (SBSES). RESULTS: Among 31 patients, 15 underwent simple debridement and 16 underwent W-plasty. In procedure time, there was no significant difference between the two groups. No complications were observed in either group. The median SBSES score was 4 (IQR, 3-4) in the simple debridement group and 5 (IQR, 5-5) in the W-plasty group, indicating a significant difference between the two groups (p<0.001). CONCLUSION: We achieved good results of direct W-plasty application to wound lacerations in terms of minimal scar formation. Thus, for patients with facial lacerations, we suggest that application of W-plasty to the wound debridement is more effective than the classic simple debridement.

A Comparative Study of Tissue Injury Grades, with Clinical Factors, in Patients with Hydrofluoric Acid Burns who Received Intra-arterial Infusion of Calcium Gluconate

PURPOSE: Hydrofluoric acid (HFA) causes injury via tissue penetration by the free fluoride ion. Methods for treatment of HFA burns include continuous intra-arterial infusion of calcium gluconate, which is especially useful for patients with dermal burns of the digits caused by HFA. However, no comparative study of tissue injury grade with clinical factors among patients with HFA burns treated with continuous intra-arterial infusion of calcium gluconate has been conducted in Korea. METHODS: We conducted a prospective study at the emergency department of a university teaching hospital between January 2011 and June 2013. The subjects enrolled in this study consisted of 33 patients with HFA burns. After completion of treatment, we divided the patients into three groups according to the type of skin lesions. Patients requiring a skin graft or surgical flap were included in the poor outcome group, those who had to undergo incision and drainage in the moderate outcome group, and those who did not require further treatment in the good outcome group. RESULTS: After completion of all treatments, 22 of the 33 patients were included in the good outcome group and seven in the moderate outcome group; the remaining four patients were included in the poor outcome group, as they met the above-mentioned criteria, experienced longer-lasting pain, and were more frequently treated with injection in comparison with the other patients. CONCLUSION: Patients with HFA burns with long-term pain who need frequent arterial injections despite undergoing intra-arterial calcium gluconate treatment are likely to have poor outcome; therefore, they require more proactive interventions.

A Case of Chemical Pneumonitis with Gastrointestinal Disturbance Caused by Nitric Acid Inhalation

Nitric acid is a typical strong acid that is colorless, corrosive, and flammable. It is often used for industrial purposes, such as refining, metal cleaning, and electroplating. In Korea, some cases of chemical pneumonitis from nitric acid poisoning have been reported, but to our knowledge, there have been no reports of diarrhea caused by nitric acid poisoning. A 42-year-old man visited a nearby hospital because of continuous diarrhea, coughing, and dyspnea after inhaling nitric acid fumes at his workplace the previous day. He was transferred to our hospital and admitted to the intensive care unit. He showed tachypnea and hypoxemia in our emergency department. Initial chest radiographs showed diffuse interstitial infiltrates and ground glass opacity in both lungs. The patient showed improvements in clinical symptoms and on chest radiographs after receiving oxygen and mechanical ventilation, antibiotics, and systemic glucocorticoid therapy. After 20 days he was discharged and showed no symptoms and sequelae on his 1-year follow-up.

A Case of Methanol Intoxication from Windshield Washer Fluid Ingestion Misidentified as an Alcoholic Beverage

Almost all cases of acute methanol intoxication result from ingestion. Absorption of methanol following oral administration is rapid and peak concentration occurs within 30-60 min. Foromic acid converted metabolites of methanol are responsible for its toxic effect. Methanol poisoning typically induces nausea, vomiting, abdominal pain, and mild central nervous system depression. Then there is a latent period lasting, followed by an uncompensated metabolic acidosis and visual dysfunction, depending on the dose of methanol ingested. Here we report on three patients who were victims of methanol intoxication due to ingestion of windshield washer fluid, which was misidentified as an alcoholic beverage. One patient had a mild form, which included abdominal discomfort, another patient had a moderate case, which included nausea, vomiting, and acidosis, and the other patient had severe acidosis and altered mentality and visual dysfunction. Except one case of visual dysfunction, all three patients recovered successfully following medical treatment and hemodialysis.