Multi-Walled Carbon Nanotube (MWCNT) Dispersion and Aerosolization with Hot Water Atomization without Addition of Any Surfactant

OBJECTIVES: Carbon nanotubes are an important new class of technological materials that have numerous novel and useful properties. Multi-walled carbon nanotubes (MWCNTs), which is a nanomaterial, is now in mass production because of its excellent mechanical and electrical properties. Although MWCNTs appear to have great industrial and medical potential, there is little information regarding their toxicological effects on researchers and workers who could be exposed to them by inhalation during the handling of MWCNTs. METHODS: The generation of an untangled MWCNT aerosol with a consistent concentration without using surfactants that was designed to be tested in in vivo inhalation toxicity testing was attempted. To do this, MWCNTs were dispersed in deionized water without the addition of any surfactant. To facilitate the dispersion of MWCNTs in deionized water, the water was heated to 40degrees C, 60degrees C, and 80degrees C depending on the sample with ultrasonic sonication. Then the dispersed MWCNTs were atomized to generate the MWCNT aerosol. After aerosolization of the MWCNTs, the shapes of the NTs were examined by transmission electron microscopy. RESULTS: The aerosolized MWCNTs exhibited an untangled shape and the MWCNT generation rate was about 50 mg/m3. CONCLUSION: Our method provided sufficient concentration and dispersion of MWNCTs to be used for inhalation toxicity testing.

Diagnostic Value of Elevated Liver Transaminase in Hemodynamically Stable Patients with Blunt Abdominal Trauma

PURPOSE: A patient at the emergency department (ED) with blunt abdominal trauma may still have the possibility of liver injury, even though they are hemodynamically stable. Computed tomography (CT) scanning or ultrasonography (US) is available if they are hemodynamically stable. However ultrasonography (US) has technical differences between physicians depending on their skill and computed tomography (CT) is expensive and time consuming, while liver transaminase is widely available, relatively inexpensive. Therefore, we studied diagnostic value of liver transaminase as a screening test for liver injury in hemodynamically stable patients with blunt abdominal trauma. METHODS: From March 2000 to February 2001, we treated 44 hemodynamically stable patients with suspected blunt abdominal trauma who were patients with elevated liver transaminase. An evaluation protocol including patient's age, sex, injury mechanism, history, physical examination, Glasgow Coma Scale (GCS), Revised Trauma Score (RTS), Injury Severity Scale (ISS), liver transaminase, abdominal US and abdominal CT was prospectively performed on all patients by residents and the staff of the emergency department. Based on the confirmed diagnosis of abdominal CT, patients were divided into two groups: group I with liver injury and group II without liver injury. We analysed the two groups by using the t-test and the chisquare test, and calculated the sensitivity, the specificity and the predictive value of serum aspartate aminotransferase (AST) and serum alanine aminotransferase (ALT) by using multiple cutoff values. RESULTS: There were 34 male patients (76.3%) and 10 female patients (23.7%) and the average age of all patients was 37 years. Triage RTS and GCS were, respectively, 11.7+/-0.7 and 13.9+/-2.1 in group I, and 11.4+/-1.2 and 13.2 +/-3.5 in group II, the differences between the two groups were statistically insignificant. The ISS was 26.8+/-9.4 in group I and 21.1+/-8.0 in group II, and the differences was statistically significant. AST and ALT were, respectively, 288.0+/-113.7 IU/L and 177.9+/-95.8 IU/L in group I and 148.1+/-84.8 IU/L and 95.1+/-59.8 IU/L in group II. The maximum value of the highest sensitivity and minimal specificity of AST and ALT, calculated using the receiver operator curve, were AST > 256.3 IU/L and/or ALT > 122.0 IU/L, for which the sensitivity and the specificity were 61.1% and 84.6%, and the positive and the negative predictive values were 73.3% and 75.8%, respectively. CONCLUSION: We recommend that all patient with suspected blunt abdominal trauma be evaluated using serum liver transaminase as a screening test for liver injury even though they are hemodynamically stable. If AST > 256.3 IU/L and/or ALT 122.0 >IU/L, they should be evaluated with abdominal CT to confirm liver injury.

In-hospital Utstein-style Evaluation of the CPCR Performed by ACLS Teams on Cardiac-arrest patients in a General Hospital

PURPOSE: This study assessed the results of the cardiopulmonary-cerebral resuscitation (CPCR) performed by advanced cardiovascular life support (ACLS) teams on cardiac-arrest patients in pundang - jeseang general hospital by using the in hospital Utstein style. METHODS: From march 1999 to February 2001, we collected data based on a formatted protocol by using the in hospital utstein style. The subjects were adult patients over the age of 20 years who had not experienced trauma and who had been resusciated in the hospital (the emergency department (ED), the ward, and intensive care unit, etc.) by an ACLS team. We studied three groups: group I (ED), group II (general ward), and group III (ICU). RESULTS: among 100,552 patients who were admitted, we resuscitated 152 patients (23 in group I, 83 group II, 46 group III). The number of male patient was higher than the number of female (78%/22%, 57%/43% and 53%/47%). For group I, II, and III, respectively patients between 50 and 70 years of age were predominant, and in all groups, the most witness of the cardiac arrest was the nurse. Performed CPCR methods were complex (87%, 80% and 100%), compression only (4%, 0%, 0%), defibrillation only (9%, 17% and 0%) and ventilation only (0%, 3% and 0%). Initial EKG rhythms were VT/VF (9pts 39%, 44pts 53% and 22pts 48%), PEA (9pts 39% , 23pts 28% and 19pts41%) and asystol (5pts 22%, 16pts 19% and 5pts 11%). The average intervals (minutes) from arrest to CPCR were 0.4+/-0.4, 3.1+/-2.2, 1.0+/-0.6, from arrest to initial defibrillation were 2.7+/-1.3, 4.0+/-3.2 , 3.0+/-1.1, from arrest to intubation were 0.5+/-0.4, 3.8+/-1.3 and 1.1+/-1.0 and from arrest to initial epinephrine were 1.4+/-0.7, 3.0+/-4.4, 1.5+/-1.1 The durations of resuscitation minutes were 23.1+/-22.1, 29.6+/-13.8, 19.4 +/-14.6 The rates of return of spontaneous circulation were 70% (16/23), 55% (46/83), 77% (34/46). The number of discharged patinets were 3 (13%), 8 (9.6%), 9 (45%). The number of patients alive after 1year were 2 (8.7%), 2 (3.4%), 7 (15.2%). CONCLUSION: The rate of return of spontaneous circulation (ROSC) and the number of patinets after 1 year were higher when the resuscitation was performed quickly, and the ACLS team played a great role in this result. Thus, the resuscitation education and training of nurses are very important and should be pursued continously.

Feasibility of Echocardiographic Evaluation of Ventricular Function After Short-term Course

BACKGROUND: The initial history, physical examination, and ECG assessment should focus on identification of potentially serious noncardiac or cardiac disorders, including coronary artery disease, congestive heart failure, and electrical instability at the emergency room. additionally, it is essential to define disease severity, stability and need for emergency therpy. echocardiography is a useful tool for this purppose. especially Doppler echocardiography may be more sensitive and time-saving diagnostic tool for the evaluation of patients presenting with cardiogenic symptoms. So we evaluate the feasibility of the echocardiographic measurement by emergency physicain after short-term course. METHOD AND RESULTS: Twenty volunteers(10 male, 38.8+/-9.3 years) were included in the study for measurement of myocardial performance index and established parameters of ventricular function using conventional echo-Doppler methods. Myocardial performance index: (ICT+IRT)/ET, was obtained by subtracting ejection time(ET) from the interval between cessation and onset of the mitral inflow velocity to give the sum of isovolumic contraction time(ICT) and isovolumic relaxation time(IRT). The most of mean values of echocardiogrphic parameters were not significantly different between those of cardiologist and those of emergency physicians(p<0.01). The duration for measuring myocardial performance index was shortest among echocardiographic parameters. the validity of echocardiographic parameters measured by emergency physicians was proved relatively good. CONCLUSION: It is proved to be feasible for emergency physician to perform echocardiographic evaluation of ventricular function after short-term course.

Changes of Aortic Dimensions as an Evidence of Cardiac Pump Mechanism During Cardiopulmonary Resuscitation: Transesophageal Echocardiographic Observation

BACKGROUND: Although the cardiac pump mechanists and the thoracic pump mechanism have been suggested, the mechanism of blood flow generated by precordial compression in human remains controversial. We hypothesized that, during compression systole, the proximal descending thoracic aorta would be distended by forward blood flow if the heart acts as a pump, and be contacted or unchanged if increased intrathoracic pressure generates blood flow. METHODS: Fourteen patients with cardiac angst underwent transesophageal echocardiogaphy to verify the morphologic changes of the descending thoracic aorta during standard manual cardiopulmonary resuscitation. The aortic dimensions including cross sectional area and diameters at the end of compression and of relaxation were measured proximal to and at the maximal compressing site of the descending thoracic aorta. RESULTS: At the point of maximal compression, deformations of the descending thoracic aorta were observed during compression in all patients and ratio of the longest to shortest diameter of the aorta deceased during compression than relaxation(0.58+/-0.15 versus 0.81+/-0.11, p=0.001). Cross sectional area of the aorta at the maxim compression deceased during compression than relaxation(3.01+/-1.91 versus 7.26+/-14.70 cm2, p=0.035). Ratio of the longest to shortest diameter of the proximal descending thoracic aorta remained unchanged during compression and relaxation(1.0+/- 0.88 versus 1.0+/-0.9, p=0.345). Cross sectional area of the proximal descending thoracic aorta increased during compression than relaxation(4.81+/-2.86 versus 4.29+/-2.51 cm2, p=0.011). CONCLUSION: Distention of the proximal descending thoracic aorta and deformation of the aorta at the maximal compression during the compression systole suggests that the heart act as a pump during standard manual cardiopulmonary resucitation in human.

Prediction of Failure to Survive Following In-hospital Cardiopulmonary Resuscitation

BACKGROUND AND PURPOSE: The purpose of this study is to compare two clinical predictive rules, the pre-arrestmorbidity(PAM) index and the prognosis-after-resuscitation(PAR) score, which predict failure to survive following in-hospital cardiopulmonary resuscitation(CPR). METHOD: The study population consisted of 162 consecutive adult patients who underwent CPR at Wonju Christian Hospital over a year period. The PAM index and PAR score were calculated from the most recent data available for each variable prior to cardiac arrest. Each predictive tool was compared between the group of discharge alive and the group of in-hospital mortality. Performance of the predictive scores was also compared by receiver-operating characteristic(ROC) curves where appropriate. RESULTS: PAM index of study population was 4.39+/-2.69 and PAR score was 2.99+/-3.36. PAM index in the group of discharge alive was 1.87+/-2.79, and PAM index in the group of ih-hospital mortality was 4.51+/-2.62. PAR score in the group of discharge alive was 0.75+/-1.75, and PAR score in the group of in-hospital mortality was 3.1+/-3.4. The PAM index identified 15 patients with a score>8, while the PAR score identified 39 patients with a score>4, none of whom survived. The sensitivity of the PAR score for the prediction of failure to survive was 25%, while that of the PAM index was 10%; neither index incorrectly identified a patient as a non-survivor who eventually survived. Both of predictive methods were not significantly different in the ROC curve. CONCLUSION: Although further confirmation is necessary, PAM index and PAR score may provide useful prognostic information to physicians and patients involved with decisions about do-no- resuscitate orders.

Cardiac Functions and Hemodynamic Values Related to Prognosis of The Septic Shock Patients in the Emergency Department

BACKGROUND: Septic shock is characterized by an abnormal vascular tone that has been related to various factors. Myocardial depression can also occur in septic shock. Various experimental studies have indicated that the myocardial depression could be present early in the course of septic shock. This study aimed to assess hemodynamic characteristics according to outcome of septic shock in emergency department. METHOD: The study population comprised 20 patients admitted to our emergency department for septic shock. All patients with septic shock(prolonged hypotension, signs of tissue hypoperfusion, signs of sepsis, suspected source of infection, or documented bacteremia) had conventional serial hemodynamic evaluations in emergency department to identify early hemodynamic variables that predicted outcome. All patients were monitored with a pulmonary artery catheter and an arterial catheter. Hemodynamic measurements and oxygen profile were obtained. RESULTS: There were 9(53%) survivors and 8(47%) nonsurvivors. There were no significant differences in systolic pressure, pulse rate, mean pulmonary artery pressure, pulmonary capillary wedge pressure, systemic vascular resistance index, and pulmonary vascular resistance index between survivors and nonsurvivors at initial hemodynamic value. However, significant differences were found in cardiac index(4.3+/-0.5 vs. 2.74+/-0.7 L/min/m2), stroke volume index(44+/-10 vs. 23+/-5 ml/beat/m2), left ventricular stroke work index(39+/-11 vs. 15+/-6 gm m/m2), and right ventricular stroke work index(8.1+/-3.0 vs. 5.2+/-2.9 gm m/m2) between survivors and nonsurvivors at initial hemodynamic value. CONCLUSION: Survivors had better myocardial function than nonsurvivors during the early phase of septic shock. This results suggest that myocardial depression during septic shock develops in the early course of septic shock, which is associated with outcome.

Role of Two-Dimensional Echocardiography in Diagnosis of Cardiovascular Injuries in Blunt Chest Trauma

BACKGROUND: Cardiovascular injury is a potentially fatal complication of blunt chest trauma. The diagnosis of cardiovascular injury in blunt chest trauma is not easy because of concomittent injuries of thoracic cage or lungs and early death from cardiovascular injury. Diagnostic tools such as electrocardiography or cardiac enzyme studies are not specific to cardiovascular injury. Two-demensional echocardiography can visualize anatomic and functional disturbances from cardiovascular injuries in patients with blunt chest trauma. Purpose: This study was designed to evaluate the usefulness of echocardiography in detecting cardiovascular injury of patients with blunt chest trauma. METHODS: We performed echocardiography for detecting cardiovascular injury in 151 patients with significant blunt chest trauma including sternal fracture, multiple rib fractures or pulmonary contusion. Echocardiography was performed within 6 hours since patient arrived emergency department. Electrocardiography was traced on arrival and 24 hours after admission. Serial determinations of cardiac enzymes including MB fraction of creatinine phosphokinase were also performed every 8 hours after admission. RESULTS: 37(25%) patients had echocardiographic evidences of cardiovascular injury. Abnormal echocardiographic findings were 10 pericardial effusion, 9 regional wall motion abnormality(RWMA) outright ventricle, 5 aortic injuries, 4 reduced left ventricular ejection fraction, 3 RWMA of left ventricle, 2 right ventricular dilatation, 2 valve injuries, and 2 other cardiovascular injuries. Electrocardiographic abnormalities were associated with echocardiographic findings. However, CK-MB/CK ratio was not associated with echocardiographic findings. Significant proportion(65%) of patients with abnormal echocardiographic findings needed cardiovascular management during hospital stay. CONCLUSION: Two-dimensional echocardiography is useful for detecting cardiovascular injury. Echocardiographic abnormality in blunt chest trauma is associated with high probability of need of cardiovascular management.

Application of Emergency Transcutaneous Cardiac Pacing in Hemodynamically Unstable Patients with Bradyarrhythmia in the Emergency Department

Transcutaneous cardiac pacing(TCP) is a rapid, safe, noninvasive and easily utilized form of emergency cardiac pacing, with hemodynamically similar to transvenous cardiac pacing. This paper reports the result of transcutaneous pacing in a series of patients in emergency department.32 patients with bradyanhythmia were enrolled during the study period. TCP was successful in 29(91%) patients. No evidence of electrical capture was seen in two patients in asystole and a patient with ventricular escape rhythm. Mean capture threshold was 66 mA. Transvenous pacemaker was inserted in 18(56%) of the 32 patients during transcutaneous cardiac pacing. Twenty(61%) of the 32 patients survived and eventually discharged. Ten patients(31%) were died of uncorrectable underlying disease in spite of successful ECG capture and palpable pulse by TCP. In conclusion, TCP is a reliable, noninvasive method that offers the possibility to initiate pacing within seconds and can be used by any emergency medical staff. In our opinion, it should be considered as the first choice of emergency treatment of hemodynamically unstable bradyarrhythmia.

The Safety of Emergency Transesophageal Echocardiography in the Dlagnosis of Thoracic Aortic Diseases

BACKGROUND: Early recognition of thoracic aortic disease is critical to reduce morbidity and mortality. Transesophageal echocardiography(TEE) has recently proved superior to traditional diagnostic modalities such as computed tomogram(CT) scan, aortography and magnetic resonance imaging(MRI) in assessing thoracic aortic diseases because of high sensivity and portability. However, the safety of emergency TEE has never been evaluated in patients with acute aortic disease in the emergency department. The purpose of this study was to evaluate the safety of TEE as an emergency diagnostic procedure to detect thoracic aortic diseases. METHOD: From May 1994 to July 1996,25 patients who were suspicious of thoracic aortic disease and underwent TEE as the first diagnostic tool in the emergency department were enrolled. Biplane TEE was used under the administration of low-dose benzodiazepine and phayngeal spray of lidocaine. Airway protection by endotracheal intubation was done if the patient had no gag reflex or unconsciousness. RESULT: Among the 25 patients including 16 patients with nontraumatic cause and 9 patients with trauma, 18 patients had thoracic aortic diseases on TEE. Three of 9 patients with trauma had aortic injury(an aortic tear, an aortic aneurysm, an aortic subintimal hematoma). Fifteen of 16 patients with nontraumatic cause revealed aortic dissection on TEE. Systolic blood pressure and heart rate were not significantly changed by TEE. There was no complication during TEE in 23 patients(92%). Severe hypertension was noted in a patient and cardiac tamponade from previous pericardial effusion was developed in a patient during TEE. CONCLUSION: Our observation suggests that TEE is a safe diagnostic modality to detect thoracic aortic diseases in the emergency department.

Analgesic Efficacy of Nitrous Oxide During Fracture Reduction in the Emergency Department

BACKGROUND: induction of analgesia is frequently required during undergoing reduction of fractures or dislocation in the emergency department. METHODto induce analgesia should be easy, convenient, and safe because patients are not always in fasting state. Nitrous oxide inhalation has been known as a good method of analgesia in emergency patients. PURPOSE: This study was aimed to evaluate the efficacy and safety of nitrous oxide analgesia in the emergency department. METHOD: We prospectively studied 34 patients undergone reductions of fractures in the emergency department. Nitrous-oxide was the sole source of analgesia. The Visual Analogue Scale(VAS) was rated by the emergency physician before nitrous oxide inhalation,5 minutes after inhalation and reduction procedures. RESULTS: No complication such as vomiting, respiratory depression, or a change in oxygen saturation resulted from the use of nitrous-oxide. Ninety one percent of patients obtained an analgesic effect. However, 9% of patients did not experience any analgesic effect after inhalation of nitrous oxide. In subgroup analysis for analgesic effect of nitrous-oxide, nitrous oxide provided only partial analgesia for acute pain in open fracture group. VAS was significantly lower after inhalation than before inhalation of nitrous oxide in simple fracture group. However, VAS of simple fracture group was increased during closed reductions, which indicated incomplete relief of pain by nitrous oxide. Nitrous oxide inhalation foiled to relieve pain during reduction in patients with open fracture or dislocation. CONCLUSION: Administration of nitrous-oxide, when used as the sole source of analgesia, is not the ideal method of analgesia during reduction of fractures or dislocations.

The Factors Associated with Fractures by Ski Injuries

BACKGROUND: Ski injuries depend on many factors which involve the skier's skill, the skiing environment, and skier's equipment. The purpose of this study was to determine the factors associated with fractures by skiing accident. SUBJECT: We evaluated 566 patients with ski injuries who visited to the emergency post located in the YongPyong Ski Resorts from Nov. 1996 to Feb. 1997. Among the patients,379 patients had no fracture(group I) and 187 patients had fracture(group II). RESULT: There was no differences in mean age and sex ratio between two groups. Fractures of the lower extremities were more common than the upper extremities. Slipping was the most common injury mechanism. arming-up was done in 40% of group I and in 17% of group II. The fracture injuries were more common in the skier with intermediate(45%) skill than the beginner(29%) and the ones with advanced skill(12%). The slope with intermediate difficulty was the most frequent site of fracture accidents. The fracture group tended to choose the slope beyond their skiing ability. CONCLUSION: Our results suggest that fracture during skiing can be prevented if skiers do warming-up prior to skiing and choose slope appropriate to their skiing skill.

Diagnosis of Myocardial Injury in Blunt Chest Trauma

PURPOSE: This study was designed to evaluate diagnostic accuracy of serial electrocardiograms(ECG), myocardial band of creatinine phosphokinase(CK)(CK-MB/CK ratio) and two dimensional echocardiography(ECHO) for myocardial injury in patients with blunt chest trauma. METHODS: We prospectively investigated 54 patients(male : 38, female : 16, mean age : 41) with severe blunt chest trauma. Presence of myocardial injury was determined by increase(>0.1ug/L) of peak serum troponin T(TnT) concentration from serial mesurements. RESULTS: Among 54 patients with blunt chest trauma, 23 patients(43%) had increased peak TnT level which suggested of myocardial injury. Among 23 patients with increased TnT, abnormal ECG findings were found in 18(78%) and echocardiographic abnormalities were observed in 17(74%). Cardiovascular events in 9(39%) of 23 patients with increase Tnt. There was no cardiovascular events in patients with normal TnT. CONCLUSION: Significant proprotion of patients with blunt chest trauma had elevated TnT value which suggested of myocardial injury. We recommend echocardiagraphy and serial tracing of ECG to verify the clinical significance of elevated TnT in patients with blunt chest trauma.

Clinical Evaluation Of Surgical Treatments For Displaced Lens: Tranafixation And Para Plana Technique

We experienced 20 patient's 21 eyes of lens displacement including subluxation(16 eyes) and luxation(5 eyes) which were surgically treated by two methods; trans-scleral fixation(14 eyes) and pars plana approach(7 eyes). The causes of lens displacement were trauma(10 eyes), unknown or spontaneous(6 eyes), congenital(2 eyes) and iatrogenic(3 eyes). All patients were male, except 2 female and aging from 11 to 75 years(mean 48.4 years). Post-operative vision showed varying degrees of improvement although 3 showed no change and 1 eye was enucleated for accompanying disorders. Increased intraocular pressures were noticed in 13/21(61.9%) eyes preoperatively, but 3/12(25%) eyes excluding 1 enucleated eye remained high postoperatively, meaning that the intraocular pressure can be normalized by the removal of lens itself. We concluded that these two methods would be adequate modalities for the management of displaced lens, and these two methods share some benifit/drawback over each other. In case of hard nucleus, the pars plana technique must be done very carefully because the fallen, whirling nuclear debris might damage the posterior pole. It may be necessary to switch to the transfixation mehtod.

Two Cases of Tuberous Sclerosis

Retinal hamartomas are the most common ocular abnormalities in up to 50% of patients with tuberous sclerosis. Other ocular lesions are retinal pigment epitheliallesions and salmon-colored nodules in the eyelid and conjunctiva. We have experienced two cases of tuberous sclerosis. The first patient was a 13 year-old female with type 1 and type 2 of retinal hamartomas and retinal pigment epithelial lesion. The second patient was a 19-year-old male with type 1 and type 3 of retinal hamartomas and intracranial calcifications.