Performance of four different tools for predicting mortality in elderly patients with severe trauma

Objective@#The present study aimed to analyze and compare the prognostic performances of Revised Trauma Score (RTS), Injury Severity Score (ISS), shock index (SI), and modified Early Warning Score (MEWS) for in-hospital mortality in severe trauma. @*Methods@#This retrospective observational study included elderly (≥65 years) patients admitted for severe trauma between January 2018 and December 2018. Receiver operating characteristics analysis was performed to examine the prognostic performance of the four different tools. The primary outcome was in-hospital mortality following an injury. @*Results@#Of the 279 patients included in the study, in-hospital mortality was 20.1% (n=56). In multivariate analysis, age (odds ratio [OR], 1.055; 95% confidence interval [CI], 1.004-1.109), ISS (OR, 1.080; 95% CI, 1.008-1.157), Glasgow Coma Scale (OR, 0.842; 95% CI, 0.785-0.904), and respiratory rate (OR, 1.261; 95% CI, 1.071-1.486) were independently associated with in-hospital mortality. The area under the curves (AUCs) of MEWS, RTS, ISS, and SI were 0.851 (95% CI, 0.763-0.857), 0.733 (0.677-0.784), 0.664 (0.606-0.720), and 0.567 (0.506-0.626), respectively. The AUC of MEWS was significantly different from those of RTS (P=0.034), ISS (P=0.001), and SI (P<0.001). @*Conclusion@#MEWS has the highest prognostic performance for in-hospital mortality among four different tools in elderly patients with severe trauma.

Effect of pralidoxime on coronary perfusion pressure during cardiopulmonary resuscitation in a pig model

OBJECTIVE: Pralidoxime is widely used for the treatment of organophosphate poisoning. Multiple studies have reported its vasoconstrictive property, which may facilitate the restoration of spontaneous circulation (ROSC) after cardiac arrest by increasing the coronary perfusion pressure (CPP). 2,3-Butanedione monoxime, which belongs to the same oxime family, has been shown to facilitate ROSC by reducing left ventricular ischemic contracture. Because pralidoxime and 2,3-butanedione monoxime have several common mechanisms of action, both drugs may have similar effects on ischemic contracture. Thus, we investigated the effects of pralidoxime administration during cardiopulmonary resuscitation in a pig model with a focus on ischemic contracture and CPP.METHODS: After 14 minutes of untreated ventricular fibrillation, followed by 8 minutes of basic life support, 16 pigs randomly received either 80 mg/kg of pralidoxime (pralidoxime group) or an equivalent volume of saline (control group) during advanced cardiovascular life support (ACLS).RESULTS: Mixed-model analyses of left ventricular wall thickness and chamber area during ACLS revealed no significant group effects or group-time interactions, whereas a mixed-model analysis of the CPP during ACLS revealed a significant group effect (P=0.038) and group-time interaction (P<0.001). Post-hoc analyses revealed significant increases in CPP in the pralidoxime group, starting at 5 minutes after pralidoxime administration. No animal, except one in the pralidoxime group, achieved ROSC; thus, the rate of ROSC did not differ between the two groups.CONCLUSION: In a pig model of cardiac arrest, pralidoxime administered during cardiopulmonary resuscitation did not reduce ischemic contracture; however, it significantly improved CPP.

The Association between Dyscarbia and Outcome in Out-of-hospital Cardiac Arrest Survivors Treated with Therapeutic Hypothermia

PURPOSE: There is a lack of clinical evidence in terms of the association between carbon dioxide tension and outcomes in cardiac arrest survivors treated with therapeutic hypothermia (TH). We investigated the association of time-weighted mean carbon dioxide tension (TWMCO2) and outcomes in out-of-hospital cardiac arrest (OHCA) survivors treated with TH. METHODS: This was a retrospective cohort study including 177 OHCA survivors. The patients were divided into three groups according to the values of TWMCO2 (normocarbia, 35~45 mmHg; hypocarbia, 45 mmHg). The primary outcome was in-hospital mortality and the secondary outcome was neurologic outcome at discharge. We assessed neurologic outcome at hospital discharge using the Cerebral Performance Categories (CPC). Neurologic outcome was dichotomized as either good neurologic outcome (CPC1 and CPC2) or poor neurologic outcome (CPC 3 to 5). The odds ratio with 95% confidence interval (CI) was estimated. RESULTS: The median value of PaCO2 was 38.2 (33.9-43.3) mmHg. Among a total of 1,239 PaCO2 values, normocarbia, hypocarbia, and hypercarbia were 618 (49.8%), 380 (30.7%), and 241 (19.5%), respectively. Results of univariate logistic regression analysis showed that hypocarbia had a significantly high odds ratio for in-hospital mortality (2.474 (95% CI, 1.129-5.424), p=0.024) compared with normocarbia. Results of multivariate logistic regression analysis showed that hypocarbia (2.926; 95% CI, 1.212-7.066; p=0.017) and hypercarbia (4.673; 95% CI, 1.348-16.205; p=0.015) had a significantly high odds ratio for in-hospital mortality compared with normocarbia. CONCLUSION: In OHCA survivors treated with TH, dyscarbia (hypocarbia and hypercarbia) was frequent and dyscarbia showed an association with in-hospital mortality.

The Relation between Time-weighted Mean Oxygen Tension and Outcome in Out-of-hospital Cardiac Arrest Survivors Treated with Therapeutic Hypothermia

PURPOSE: Studies to determine the relation between oxygen tension and outcome in cardiac arrest survivors treated with therapeutic hypothermia (TH) are lacking. We investigated the relation of time-weighted mean oxygen tension (TWMO2) and outcome in cardiac arrest survivors treated with TH. METHODS: This was a retrospective observational study including 177 out-of-hospital cardiac arrest (OHCA) survivors. The patients were divided into four categories according to quartile values of TWMO2. The primary outcome was neurologic outcome at discharge and the secondary outcome was all cause in-hospital mortality. We assessed neurologic outcome using the Cerebral Performance Categories (CPC) at hospital discharge. Neurologic outcome was dichotomised as either good neurologic outcome (CPC1 and CPC2) or poor neurologic outcome (CPC 3 to 5). The odds ratio with 95% confidence interval (CI) was estimated. RESULTS: The median value of PaO2 was 139(104.5-170.0) mmHg. Among a total of 1,239 PaO2 values, 22(1.8%) values were hypoxia (300 mmHg). Results of univariate logistic regression analysis showed a significantly low odds ratio for poor neurologic outcome [0.353(95% CI, 0.133-0.938) and 0.321(95% CI, 0.121-0.850), respectively] and for in-hospital mortality [0.338(95% CI, 0.132-0.870) and 0.387(95% CI, 0.154-0.975), respectively] for the third quartile and the fourth quartile. However, results of multivariate logistic regression analysis showed no significant relation between TWMO2 and outcomes. CONCLUSION: In OHCA survivors treated with TH, time-weighted oxygen tension did not show an association with neurologic outcome and in-hospital mortality.

Early Initiation of Therapeutic Hypothermia after Sudden Out-of-Hospital Cardiac Arrest

PURPOSE: Therapeutic hypothermia (TH) improves the probability of survival and neurologic recovery after resuscitation from out-of-hospital cardiac arrest (OHCA). However, the best time to initiate TH after the return of spontaneous circulation (ROSC) remains unknown. METHODS: The aim of this study was to evaluate the correlation between TH initiation time after ROSC and the resulting neurological outcome. Methods: A retrospective analysis was performed on 122 OHCA patients enrolled between January 2008 and December 2011. Therapeutic hypothermia (32~34degrees C) was induced immediately after ROSC. The primary measure of outcome was neurological function at hospital discharge, as determined by a cerebral performance category (CPC) scale. RESULTS: Out of the 122 patients, 34 patients (27.9%) had a good neurological outcome at hospital discharge. The initiation time following ROSC was shorter, although not statistically significant, in patients with good neurological outcomes compared to those with poor outcomes. Based on subgroup analysis, only the shockable rhythm group showed a significant difference, in the time after ROSC to TH initiation, between good and poor neurological outcome groups. Receiver operator characteristic analysis suggested that an initiation time of 250 min after ROSC was most predictive of CPC 1-2 outcomes compared to other time points. Furthermore, the 250 min initiation time after ROSC correlated with neurological outcome in patients with OHCA undergoing TH treatment. CONCLUSION: Compared to late initiation, early initiation (within 250 min) with TH had neurologic benefits for patients with OHCA.

Initial Laboratory Parameters and its Correlation to Intermediate Syndrome in Patients with Acute Organophosphate Poisoning

PURPOSE: The association of serial serum cholinesterase (SChE) activity and the occurrence of intermediate syndrome (IMS) in patients orally poisoned with organophosphate (OP) were investigated. In addition, other clinical and laboratory factors were assessed for their ability to predict the subsequent development of IMS. METHODS: A total of 114 patients presented to our emergency department with acute OP ingestion between 2007 and 2012 were enrolled in this prospective study. Of these patients, 67 who needed mechanical ventilation (MV) over five days were divided into the IMS group. The 47 patients weaned from MV within four days after admission, or who did not receive the assistance of MV, were placed in the non-IMS group. The level of SChE at admission, 48 hours, and 96 hours, at discharge after admission were checked. The APACHE II (Acute Physiology, Age, Chronic Health Evaluation II) score, the amount ingested, exposure route, gender, age, and the laboratory test results were collected. All statistical analyses were performed using the Statistical Package for the Social Sciences (version 20.0). RESULTS: The mean age of total enrolled patients was 53.7+/-17.9 years and 73 patients (64.0% of total patients) were male. There were 102(89.5%) patients who intentionally ingested the OP and the mean amount ingested was 102.5+/-64.9 mL. The mean time after patients sought medical care was 5.4+/-10.5 hours after ingestion. The level of SChE at admission was 1,586+/-796 U/L and the APACHE II score was 28.81+/-19.7. The arterial pH, bicarbonate and carbon dioxide pressure, and serum protein and albumin were significantly lower in the IMS group than the non-IMS group (p<0.001). In contrast, the serum amylase, lipase, and glucose were higher in the IMS group. The APACHE II score, serum albumin and amylase, arterial bicarbonate, and the SChE at 48 and 96 hours after ingestion were independent factors that predicted the occurrence of IMS in patients with OP poisoning. The rate of recovery was 86.6% in the IMS group and 100% in the non-IMS group (p<0.001). CONCLUSION: Patients with a higher APACHE II score and levels of serum amylase, and lower levels of serum albumin and arterial bicarbonate, may be associated with the occurrence of IMS. Furthermore, when SChE levels after 48 hours and 96 hours did not increase, compared with the level of SChE at admission, patients tended to show IMS.

Initial Laboratory Parameters and its Correlation to Intermediate Syndrome in Patients with Acute Organophosphate Poisoning

PURPOSE: The association of serial serum cholinesterase (SChE) activity and the occurrence of intermediate syndrome (IMS) in patients orally poisoned with organophosphate (OP) were investigated. In addition, other clinical and laboratory factors were assessed for their ability to predict the subsequent development of IMS. METHODS: A total of 114 patients presented to our emergency department with acute OP ingestion between 2007 and 2012 were enrolled in this prospective study. Of these patients, 67 who needed mechanical ventilation (MV) over five days were divided into the IMS group. The 47 patients weaned from MV within four days after admission, or who did not receive the assistance of MV, were placed in the non-IMS group. The level of SChE at admission, 48 hours, and 96 hours, at discharge after admission were checked. The APACHE II (Acute Physiology, Age, Chronic Health Evaluation II) score, the amount ingested, exposure route, gender, age, and the laboratory test results were collected. All statistical analyses were performed using the Statistical Package for the Social Sciences (version 20.0). RESULTS: The mean age of total enrolled patients was 53.7+/-17.9 years and 73 patients (64.0% of total patients) were male. There were 102(89.5%) patients who intentionally ingested the OP and the mean amount ingested was 102.5+/-64.9 mL. The mean time after patients sought medical care was 5.4+/-10.5 hours after ingestion. The level of SChE at admission was 1,586+/-796 U/L and the APACHE II score was 28.81+/-19.7. The arterial pH, bicarbonate and carbon dioxide pressure, and serum protein and albumin were significantly lower in the IMS group than the non-IMS group (p<0.001). In contrast, the serum amylase, lipase, and glucose were higher in the IMS group. The APACHE II score, serum albumin and amylase, arterial bicarbonate, and the SChE at 48 and 96 hours after ingestion were independent factors that predicted the occurrence of IMS in patients with OP poisoning. The rate of recovery was 86.6% in the IMS group and 100% in the non-IMS group (p<0.001). CONCLUSION: Patients with a higher APACHE II score and levels of serum amylase, and lower levels of serum albumin and arterial bicarbonate, may be associated with the occurrence of IMS. Furthermore, when SChE levels after 48 hours and 96 hours did not increase, compared with the level of SChE at admission, patients tended to show IMS.

Effect of the Community Education Program on the Attitude on the Emergency Medical Service and Safety in a Rural Emergency Medical Service System

PURPOSE: Compared to urban areas, access to emergency medical services in rural areas is relatively restricted both in quality and quantity. However, based on the aged population model, the need for such services is greater in rural areas, due to accidents and underlying disease. We set out to investigate whether education for emergency medical services would be helpful for utilization of poor resources for emergency medical services in rural areas and how efficient it might be. METHODS: Goheung (n=796) and Haenam (n=819), which appeared to be similar in terms of area, population composition, and quality and quantity of emergency medical services, were selected. While one area received Life Helper for the Village, one of the educational programs for emergency medical services, the other did not. A questionnaire containing items on recognition of emergency medical services and roles of the primary responder was administered. RESULTS: Significant differences were observed in the recognition of emergency medical services and safety awareness in Goheung, to which education for emergency medical services was provided. However, we did not find a relationship between injury or accident development and education for the rural emergency medical service system in two areas. CONCLUSION: Thus, provision of education is needed for development of common residents into primary responders in alienated rural and fishing villages, offering them ongoing and repeating education in order to increase their recognition of emergency medical services and safety awareness, and expand such education to areas that are in a similar situation.

Gray/White Matter Ratio as an Outcome Predictor for Cardiac Arrest Patients Treated by Therapeutic Hypothermia

PURPOSE: Ischemic brain injury following cardiac arrest presents as cerebral edema. Cerebral edema can be diagnosed using computed tomography (CT) by evidence of difference in the ratio between gray and white matter density. The prognostic value of CT scan use in determining neurologic outcomes remains unclear for cardiac arrest survivors treated with therapeutic hypothermia. We investigated the density of gray and white matter and found that their ratio was associated with neurologic outcome. METHODS: Our study data included 93 cardiac arrest survivors treated with therapeutic hypothermia from January 2008 to June 2011. Cranial CT was performed after the return of spontaneous circulation. Circular regions of CT measurement (9.4 mm2) evaluated locations of interest including the caudate nucleus, putamen, posterior limb of the internal capsule, and the corpus callosum. The average attenuation in Hounsfield Units (HU) for each region was recorded. Neurological outcome was ranked as good or poor at discharge with neurological outcome assessed according to the Cerebral Performance Category scale (CPC) with a poor outcome defined as a CPC of 3-5. RESULTS: Gray matter attenuation was found to be significantly different between the good and poor outcome cases while white matter attenuation was insignificant. All types of gray/white matter ratio were significantly different between two groups. Receiver operating characteristics analysis determined a cut-off value of gray/white matter ratio at less than 1.11 (sensitivity 29.8%) which results in a poor outcome with a specificity of 100%. CONCLUSION: A low gray/white matter ratio (<1.11), as evaluated by CT scan, is associated with poor outcome after cardiac arrest and therapeutic hypothermia. However, the results of a CT scan should be interpreted with caution as the gray/white matter ratio is a low sensitivity marker.

Neuron Specific Enolase as a Biomarker Predicting Neurological Outcome after Cardiac Arrest in Patients Treated by Therapeutic Hypothermia

PURPOSE: Neurological outcome prediction is an important aspect of post-resuscitation care in cardiac arrest survivors. The appearance of high serum neuron specific enolase (NSE) is known to be associated with ischemic brain injury and poor neurological outcome. The application of therapeutic hypothermia to cardiac arrest survivors has been shown to improve neurological outcomes. As such, we investigated the predictive value of serial serum NSE levels in patients who were resuscitated from cardiac arrest. METHODS: This study included 123 cardiac arrest survivors who were treated by therapeutic hypothermia from January 2008 to June 2011. Blood samples used for evaluating NSE were collected at return of spontaneous circulation (ROSC) at 6, 24 and 48 hours after initiation of therapeutic hypothermia. Neurological outcome was graded as 'good' or 'poor' at discharge and assessed according to the Cerebral Performance Category scale (CPC). A poor outcome was defined as a CPC value of 3-5. RESULTS: Receiver operating characteristic (ROC) analysis revealed NSE cut-off values of 53.9 microg/L (sensitivity 14.6%), 48.5 microg/L (sensitivity 30.6%), 80.0 microg/L (sensitivity 40.0%), and 52.7 microg/L (sensitivity 55.5%) for poor outcomes with a specificity of 100%, measured at ROSC of 6, 24 and 48 hours after initiation of therapeutic hypothermia, respectively. The poor outcome group showed significant change in NSE concentration over time (p=0.002), while the good outcome group did not. CONCLUSION: Detection of NSE at the cut-off value, 48 hr after initiation of therapeutic hypothermia was a specific but moderately sensitive marker of poor outcome at discharge. Single measurements of NSE should be cautiously interpreted, but NSE change over time was helpful in predicting the neurologic outcome.

Neuron Specific Enolase as a Biomarker Predicting Neurological Outcome after Cardiac Arrest in Patients Treated by Therapeutic Hypothermia

PURPOSE: Neurological outcome prediction is an important aspect of post-resuscitation care in cardiac arrest survivors. The appearance of high serum neuron specific enolase (NSE) is known to be associated with ischemic brain injury and poor neurological outcome. The application of therapeutic hypothermia to cardiac arrest survivors has been shown to improve neurological outcomes. As such, we investigated the predictive value of serial serum NSE levels in patients who were resuscitated from cardiac arrest. METHODS: This study included 123 cardiac arrest survivors who were treated by therapeutic hypothermia from January 2008 to June 2011. Blood samples used for evaluating NSE were collected at return of spontaneous circulation (ROSC) at 6, 24 and 48 hours after initiation of therapeutic hypothermia. Neurological outcome was graded as 'good' or 'poor' at discharge and assessed according to the Cerebral Performance Category scale (CPC). A poor outcome was defined as a CPC value of 3-5. RESULTS: Receiver operating characteristic (ROC) analysis revealed NSE cut-off values of 53.9 microg/L (sensitivity 14.6%), 48.5 microg/L (sensitivity 30.6%), 80.0 microg/L (sensitivity 40.0%), and 52.7 microg/L (sensitivity 55.5%) for poor outcomes with a specificity of 100%, measured at ROSC of 6, 24 and 48 hours after initiation of therapeutic hypothermia, respectively. The poor outcome group showed significant change in NSE concentration over time (p=0.002), while the good outcome group did not. CONCLUSION: Detection of NSE at the cut-off value, 48 hr after initiation of therapeutic hypothermia was a specific but moderately sensitive marker of poor outcome at discharge. Single measurements of NSE should be cautiously interpreted, but NSE change over time was helpful in predicting the neurologic outcome.

Adequacy of Epinephrine Administration during Advanced Cardiovascular Life Support in terms of Dosing and Intervals between Doses / 대한구급학회지

BACKGROUND: Consensus guidelines clearly define how epinephrine is administered during cardiopulmonary resuscitation (CPR). In South Korea, it is not known whether epinephrine is administered in accordance with the current advanced cardiovascular life support (ACLS) guidelines during actual practice. We sought to investigate adherence to ACLS guidelines during actual CPR in terms of the dose of epinephrine and the interval between doses. METHODS: A retrospective review of medical records was performed on 394 adult cardiac arrest patients who received CPR at an emergency room. Data including the duration of CPR, the dose of epinephrine, and the interval between doses was collected from CPR records. RESULTS: Standard-dose epinephrine (1 mg) was used in 166 of 394 patients (42.1%). In 58.8% of patients, the average between-dose interval was within the 3-5 min recommended in the guidelines, whereas it was shorter than 3 min in 31.4% of patients. As a whole, epinephrine was administered in accordance with the current ACLS guidelines in only 96 of 394 patients (24.4%). Logistic regression analysis revealed the duration of CPR to be an independent factor affecting the use of standard-dose epinephrine and the adequate between-dose interval. CONCLUSIONS: Epinephrine was not administered according to the ACLS guideline in most patients. A national multi-center study is required to determine whether the poor adherence to the ACLS guideline is a widespread problem. In addition, efforts to improve adherence to the ACLS guideline are required.

Analysis of Factors Influencing the Severity of Cultivator-Related Trauma patients and Correlation between these Factors

PURPOSE: Rural areas of Korea are already aged societies, and the victims of trauma in these areas are increasingly associated with an elderly demographic and farm equipment use. In addition, rural medical services are often not well supported. The purpose of this study was to evaluate the factors that influence the severity and prognosis of cultivator-related trauma, and the correlations between these factors. METHODS: We retrospectively analyzed patients who visited the Chonnam National University Hospital emergence center due to cultivator-related trauma, from January 2006 to December 2010. The injury severity of these patients was analyzed according to the injury severity score (ISS), the revised trauma score (RTS), the new injury severity score (NISS) and the trauma score and injury severity score (TRISS). RESULTS: A total of 376 cases, 322 male and 54 female, of cultivator-related trauma were reviewed. Patient ages ranged from 25 to 85 years (median, 57 years). Patients were divided into two age groups, those older than 65-years of age and those younger than 65. The primary causes of traumatic injury were falling down (57.2%), and vehicle overturning (16.5%). The site most frequently injured was the chest (35.1%). Rate of acute complication was 29.8% and operation was required in 41% of cases. The average ISS was 9.0 (median range [quartile], 4-16). ISS, NISS, RTS and TRISS were statistically correlated with the mechanism of injury, site of injury, and mortality and complication rates. In particular, TRISS was significantly lower in cultivator-related trauma for those older than 65-years of age. CONCLUSION: Among the severity indexes in assessing cultivator-related trauma, TRISS is helpful in assigning severity and predictable index in older, rural patients. However, this result is not representative of all possible cultivator-related traumas. A new statistical model is necessary to accurately analyze the severity and mortality in cases of cultivator-related trauma.

Gene expression profiling of mouse aborted uterus induced by lipopolysac charide / 대한해부학회지

To identify genes that participate in the abortion process, normal pregnant uteri were compared to lipopolysaccharide (LPS)-induced abortion uteri. At day 6 of pregnancy, mice were treated with LPS at various time points to induce an abortion. Total RNAs were applied to a cDNA microarray to analyze genes with altered expression. At the early stage (2 hours) of LPS-induced abortion, upregulated genes were mainly composed of immune responsive genes, including Ccl4, Ccl2, Cxcl13, Gbp3, Gbp2, Mx2, H2-Eb1, Irf1 and Ifi203. Genes related to toll-like receptor signaling were also overexpressed. At late stages of abortion (12-24 hours), many genes were suppressed rather than activated, and these were mainly related to the extracellular matrix, cytoskeleton, and anti-apoptosis. Altered expression of several selected genes was confirmed by real time reverse transcription-polymerase chain reaction. The results demonstrated that many known genes were altered in the LPS-treated pregnant uterus, implying that the molecular mechanisms of the genes involved in LPS-induced abortion are complicated. Further analysis of this expression profile will help our understanding of the pathophysiological basis for abortion.

A Case of Fatal Fenazaquin Intoxication Showing Severe Lactic Acidosis

Fenazaquin (4-[[4 (1,1-dimethylethyl) pheynyl]ethoxy]quinazoline) is an insecticide that inhibits NADH ubiquinone oxidoreductase of the mitochondria, which is also known as complex I. An 83 year old female was brought to our emergency department (ED) having been found collapsed and unconscious at home by her family. She had ingested up to 100 ml from a bottle of 20% fenazaquin solution. In the ED, she showed severe persistent lactic acidosis despite a seemingly stable hemodynamic condition. Despite intensive supportive management, including positive pressure ventilation, packed red cell transfusion, hemodialysis, and intravenous N-acetylcysteine administration, the lactic acidosis did not respond. To our knowledge, this is the first report of fenazaquin poisoning in humans. No antidote for fenazaquin is known. In this case report, we discuss clinical characteristics and possible pathophysiologic mechanism of fenazaquin poisoning with a literature review.

Two Cases of Comatose Patients Presenting after Exposure to Hydrogen Sulfide Gas

Hydrogen sulfide is a by-product of decayed organic material and is ubiquitously found as an ingredient of manufacturing reagents or as an undesirable by-product of the manufacturing or industrial processing. Hydrogen sulfide is a chemical asphyxiant and interferes with cytochrome oxidase and aerobic metabolism. It has thus been deemed an important cause of work-related sudden death. This gas is particularly insidious due to the unpredictability of its presence and concentration and its neurotoxicity at relatively low concentrations, causing olfactory nerve paralysis and loss of the warning odor. Here, we report two cases of comatose patients presenting after accidental exposure to hydrogen sulfide gas.

Predictors of Mortality in Hemodynamically Unstable Traumatic Patients with Pelvic Fracture

PURPOSE: Pelvic fracture is one of the more serious skeletal injuries, resulting in substantial mortality. The large amount of kinetic energy necessary to fracture the bony pelvis often leads to concomitant thoraco-abdominal injury. Pelvic fracture and combined injuries need effective initial resuscitation. However, it is hard to predict mortality due to the complexity of multiple injuries. Therefore, the purpose of this study was to identify factors predicting mortality in patients with pelvic fracture and concomitant thoraco-abdominal injury. METHODS:A retrospective study was performed on 174 cases of pelvic fracture who visited the Emergency Department between January 2003 and June 2008. Data were collected regarding demographic characteristics, mechanism of injury, injury severity score (ISS), Abbreviated Injury Score (AIS), Simplified Acute Physiologic Score II (SAPS II), transfusion requirements, fluid requirements, the findings on angiography, hemoglobin level, platelet count, prothrombin time (PT), fibrinogen, albumin, base deficit, lactate, anti-thrombin III, length of ICU stay, and total hospitalization days. Pelvic fracture categories were derived by adapting the Young-Burgess classification. RESULTS: One hundred forty patients survived (Group I); 34 died (Group II). Blood pressure, pulse rate, hemoglobin, albumin, lactate, base deficit, PT, fibrinogen and Antithrombin III were significantly different between two groups. Transfusion, fluid requirements, ISS and SAPS II were significantly higher in group II. Extravasation on the CT was more frequent found in group II. The ISS 1.194 (95% CI, 1.076~1.325) and SAPS II 1.162 (95% CI,1.042~1.296) were independent significant predictors of mortality. CONCLUSION: Predictors of mortality in pelvic fracture patients should be available during the first attempt at resuscitation. The ISS and SAPS II were the most important predictors in defining mortality.

Computed Tomography Grading for Predicting Esophageal Stricture in Caustic Injury

PURPOSE: The aim of this study was to investigate the ability of thoracic computed tomography (CT) to predict esophageal stricture formation and risk factors associated with the development of stricture induced by ingestion of caustic materials. METHODS:This was a study of 41 patients who had visited an emergency care center following ingestion of caustic substances sometime between January 1998 and August 2008. A retrospective analysis of medical records was performed. Findings for the esophageal lesion were classified according to changes in the esophageal wall and the infiltration of peri-esophageal soft tissue. Also, clinical, laboratory, and endoscopic data from these patients were reviewed. The correlation between the degree of esophageal damage seen on CT scans and esophageal constriction seen on esophagography were then evaluated. RESULTS: A total of 41 cases of caustic ingestion were identified (age range, 20~82 years). The most common caustic agent ingested was acid (70%). The most frequent cause for ingestion was attempted suicide (70%); the other cases (30%) were accidental ingestion. The findings on thoracic CT in the 41 patients were as follows: first-degree esophageal injury in 4 (9.8%), second-degree in 8 (19.5%), third-degree in 17 (41.6%), fourth-degree in 12 (29.3%). Fourteen patients (34.1%) developed caustic esophageal stricture. The closer the degree of esophageal damage was to grade IV, the more prevalent the esophageal constriction became. This correlation was statistically significant (p<0.001). Of the 41 patients, 26 underwent endoscopy at an early stage after they visited an emergency care center. An analysis of the correlation between the degree of esophageal damage seen on endoscopy and that seen on CT scans was performed. This revealed a significant correlation (p=0.002, r=0.585). CONCLUSION: Thoracic CT grading suggesting periesophageal soft tissue infiltration and fluid collection (grade III to IV) rather than only edema (grade I) may be associated with stricture formation. Early CT grading is safe and useful for predicting the development of stricture induced by caustic ingestion.

Comparison of the Quality of Chest Compressions between CPR Performed by a Single Trained Rescuer and Two Rescuer CPR Performed by a Trained Rescuer and an Untrained Rescuer in a Prolonged Out-of-Hospital CPR Scenario

PURPOSE: The aim of this study is to compare the quality of chest compressions between cardiopulmonary resuscitation (CPR) performed by a single trained rescuer and two rescuer CPR performed by a trained rescuer and an untrained rescuer in a prolonged out-of-hospital CPR scenario. METHODS: For the phase I experiment, thirty-six emergency medical technician students (trained rescuers) were asked to perform 10 minutes of lone rescuer CPR on an instrumented manikin. For the phase II experiment, thirty-six volunteers with no previous CPR training (untrained rescuers) were recruited. Each untrained rescuer was randomly assigned to one trained rescuer. They were asked to perform 10 minutes of two rescuer CPR during the phase II experiment. RESULTS: During phase I, the percent of correct compressions diminished over time. The number of total compressions attempted for 10 minutes was increased significantly in phase II (786+/-50 versus 689+/-50 in phase I, p<0.01). However, the mean percentage of correct compressions for 10 minutes did not show a significant difference between phases (66+/-34% in phase I versus 64+/-22% in phase II). The duration of chest compression interruption was significantly reduced in phase II (3.0+/-0.4 versus 3.5+/-0.5 min in phase I, p<0.01). CONCLUSION: The quality of two rescuer CPR performed by a trained rescuer and an untrained rescuer was comparable to that of lone rescuer CPR performed by a single trained rescuer in a 10-min CPR scenario. When CPR goes on for a prolonged period, changing the person doing the chest compressions to an untrained rescuer may improve the quality of CPR.

Emergency Management of Thoracic Trauma

The chest is frequently injured by both penetrating and blunt trauma. The vast majority of thoracic trauma patients do not require thoracotomy and are successfully managed by tube thoracostomy and supportive measures. A critical diagnostic challenge in patients with thoracic trauma is the possibility of a life-threatening injury. Specific life-threatening thoracic injuries should be suspected, diagnosed, and treated during the initial primary survey. These are airway obstruction, tension pneumothorax, cardiac tamponade, massive hemothorax, open pneumothorax, and frail chest.