Dexamethasone promotes long-term functional recovery of neuromuscular junction in a murine model of tourniquet-induced ischaemia-reperfusion.

AIM: Tourniquet-induced ischaemia and subsequent reperfusion cause serious ischaemia-reperfusion (IR) injury in the neuromuscular junction (NMJ) and skeletal muscle. Here, we investigated whether dexamethasone (Dex) promotes long-term functional recovery of the NMJ and skeletal muscle in tourniquet-induced hindlimb IR. METHODS: Unilateral hindlimb of C57/BL6 mice was subjected to 3 h of ischaemia following 6 weeks of reperfusion (6-wk IR). Dex treatment began on the day of IR induction and lasted for different periods. Sciatic nerve-stimulated gastrocnemius muscle contraction was detected in situ. Function of the NMJ was measured in situ using electrophysiological recording of the miniature endplate potential (mEPP) and endplate potential (EPP). Western blot was used to detect protein expression of nicotinic acetylcholine receptors (nAChRs) in gastrocnemius muscles. RESULTS: Gastrocnemius muscle contraction in mice with 6-wk IR was about 60% of normal skeletal muscle contraction recorded in age-matched sham mice. The amplitude of the mEPP and EPP was lower in mice with 6-wk IR, compared to sham mice. Dex treatment for 1 or 3 days did not restore the function of the NMJ and improve gastrocnemius muscle contraction in mice with 6-wk IR. Dex treatment for 1 week exerted a maximum effect on improving the function of the NMJ and skeletal muscle, with the effect of Dex gradually lessening with prolonged Dex treatment. There are no significant differences in protein expression of nAChR-α1 and nAChR-ß1 subunits in the gastrocnemius muscle among all groups. CONCLUSION: Dex promotes repair of the NMJ and subsequently restores skeletal muscle contractile function in tourniquet-induced 6-wk IR.

Diabetes alters protein expression of hyperpolarization-activated cyclic nucleotide-gated channel subunits in rat nodose ganglion cells.

Vagal afferent neurons, serving as the primary afferent limb of the parasympathetic reflex, could be involved in diabetic autonomic neuropathy. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed in the vagal afferent neurons and play an important role in determining cell membrane excitation. In the present study, the protein expression and the electrophysiological characteristics of HCN channels were investigated in nodose ganglion (NG) afferent neurons (A-fiber and C-fiber neurons) from sham and streptozotocin (STZ)-induced diabetic rats. In the sham NG, HCN1, HCN3, and HCN4 were expressed in the A-fiber neurons; and HCN2, HCN3, and HCN4 were expressed in the C-fiber neurons. Compared to the sham NG neurons, diabetes induced the expression of HCN2 in the A-fiber neurons besides overexpression of HCN1 and HCN3; and enhanced the expression of HCN2 and HCN3 in C-fiber neurons. In addition, whole-cell patch-clamp data revealed diabetes also increased HCN currents in A-fiber and C-fiber neurons. However, we found that diabetes did not alter the total nodose afferent neuron number and the ratio of A-fiber/C-fiber neurons. These results indicate that diabetes induces the overexpression of HCN channels and the electrophysiological changes of HCN currents in the A- and C-fiber nodose neurons, which might contribute to the diabetes-induced alteration of cell excitability in the vagal afferent neurons.

The impact of a rural emergency department rotation on applicant ranking of a US emergency medicine residency program.

INTRODUCTION: Few US emergency medicine (EM) residency programs have been located in rural states due to program requirements for emergency department (ED) patient volume. Recent revision to the program requirements now permits 'educationally justifiable exceptions' to the patient population requirement, 'such as clinical sites in a rural setting', and some EM residency programs now plan to offer rural ED clinical experiences as a required curricular component. The impact of a required rural EM rotation on the ranking decisions of applicants is important to residency programs seeking to attract the most desirable applicants. OBJECTIVE: To assess the impact of a required rural ED rotation on applicant ranking of an EM residency program in the US National Resident Matching Program (NMRP). METHODS: All applicants to the study's EM residency program completing the interview portion of the application process received a mailed and emailed survey following the release of the 2004 NMRP results. The survey included questions addressing the rural/non-rural classification of the location of the applicants' childhood home, medical school, and anticipated future practice. RESULTS: Of 46 eligible subjects, 32 (69.6%) completed the survey. Of subjects with a rural childhood, 73.3% reported a positive impact on rank order (95% CI 50.9-95.7%) and 26.7% reported no impact (CI 4.3-49.1%); 81.3% of subjects with non-rural backgrounds reported no impact (CI 62.2-100%), 12.5% higher rank (CI 0-28.7%), and 6.3% lower (CI 0-18.2%). If planning a future practice in a rural community, 83.3% reported positive impact (CI 62.2-100%) and 16.7% no impact (CI 0-37.8%); 78.9% of subjects anticipating future practice in non-rural communities reported no impact (CI 60.6-97.3%), 15.8% higher rank (CI 0-32.2%), and 5.3% lower (CI 0-15.4). Of the subjects attending medical school in rural states, 52.2% reported a positive impact (CI 31.8-72.6%) and 47.8% no impact (CI 27.4-68.2%), while 75% of graduates of medical schools in non-rural states reported no impact (CI 32.6-100%) and 25% (CI 0-67.4%) a negative impact. CONCLUSION: The presence of a rural ED rotation did not adversely impact EM residency applicants' ranking of the program.

Domestic violence homicides: ED use before victimization.

The purpose of this study was to document prior emergency department (ED) use and injuries presented by victims of domestic violence (DV) homicides. We identified all female DV homicide cases investigated by Kansas City, Missouri, Police Department (KCPD) officials over 5 years. Medical Records from 12 hospitals were searched to determine how many homicide victims were in the ED within the 2 years preceding their homicide. The records were reviewed and classified according to the Flitcraft Criteria. KCPD documented 139 female homicides victims, with 34 (24.5%) of these ruled DV-related. Of these 34 victims, 15 (44%) presented to an ED within 2 years of homicide. The 15 subjects made 48 total visits, which included 20 (42%) injury-related visits. Fourteen (93%) of the victims seen in the ED presented with injuries on at least 1 encounter. Eight patients had head injuries (53.3%), 2 had perineal lacerations (13.3%), 2 had rapes (13.3%), and 1 had a suicide attempt (6.7%). The medical records of 8 (53.3%) of the 15 victims yielded at least suggestive evidence of battering. There was documented domestic violence in 2 cases and intervention in none. Because nearly half of all women who were victims of a DV-related homicide had been in the ED within 2 years before their deaths, the ED could play an important role in prevention. Approximately one half had documentation at least suggestive of battering. These results suggest the potential for universal screening, and documented safety assessments.

The occupational risk of motor vehicle collisions for emergency medicine residents.

OBJECTIVE: To determine the prevalence and risk factors associated with motor vehicle collisions (MVCs) and near-crashes as reported by emergency medicine (EM) residents following various ED shifts. METHODS: A survey was sent to all allopathic EM-2-EM-4 residents in May 1996 asking whether they had ever been involved in an MVC or near-crash while driving home after an ED shift. The residents' night shift schedules, self-reported tolerance of night work, ability to overcome drowsiness, sleep flexibility, and morningness/eveningness tendencies also were collected. RESULTS: Seventy-eight programs participated and 62% of 1,554 eligible residents returned usable surveys. Seventy-six (8%, 95% CI = 6% to 10%) residents reported having 96 crashes and 553 (58%, 95% CI = 55% to 61%) residents reported being involved in 1,446 near-crashes. Nearly three fourths of the MVCs and 80% of the near-crashes followed the night shift. Stepwise logistic regression of all variables demonstrated a cumulative association (R = 0.19, p = 0.0004) that accounted for 4% of the observed variability in MVCs and near-crashes. Univariate analysis showed that MVCs and near-crashes were inversely related to residents' shiftwork tolerance (p = 0.019) and positively related to the number of night shifts worked per month (p = 0.035). CONCLUSIONS: Residents reported being involved in a higher number of MVCs and near-crashes while driving home after a night shift compared with other shifts. Driving home after a night shift appears to be a significant occupational risk for EM residents.

The effect of a community-based intimate-partner violence advocacy program in the emergency department on identification rate of intimate-partner violence.

A retrospective medical record review assessed identification rate of women acutely injured by intimate-partner violence before and after implementation of an Emergency Department (ED) intimate-partner violence advocacy program. After program implementation, the identification rate of intimate-partner violence increased over 40%. Of the 19 physicians in the ED during both time periods, 17 (89%) identified more cases after the program began (p < 0.003). Implementation of a community-based intimate-partner violence advocacy program in the ED resulted in an increased identification rate of intimate violence.

Reflections on written comments by women on their abuse.

In a study to differentiate injuries of physical abuse from non-physical abuse, 103 women wrote uninvited comments that were analyzed in two ways: Q-sort and phenomenology analyses. Q-sort identified two categories: helplessness and assertiveness. Comparisons with subject responses about current or previous violence indicated that women who wrote assertive comments were less likely to be in a violent relationship than women who wrote helpless comments. Phenomenological analysis indicated that women who were categorized as silent, received or subjective were in abusive relationships; some had been abused on the day of admission. Two women wrote comments considered subjective procedural; both were living with their abuser and stated that the abuse no longer occurred. Health-care professionals must question the appropriate goal to counsel abused women. Whether these two continua reflect a readiness to leave the relationship or result from having left, the comments by two women who say they are no longer being abused are more assertive and appear to show higher levels of knowing.

Effects of an emergency department-based advocacy program for battered women on community resource utilization.

STUDY OBJECTIVE: The emergency department is often accessed by battered women. Although it is recommended that information about community resources be given to women, there is little information regarding how often women use these resources. The objective of this study was to determine whether an ED-based advocacy program resulted in increased community resource utilization by battered women. METHODS: The study used a before-after trial design at an urban county hospital ED. Before the program, a consecutive sample of 117 women was identified in the ED as having sustained injuries by domestic violence. After the program, a consecutive sample of 105 (57% of the 183 asked) who agreed to meet with an advocate in the ED was identified. Participants in both groups lived in Kansas City, Missouri, and were 18 years of age or older. The outcome measures were the proportion of women with shelter use, shelter-based counseling, police calls, full orders of protection, and repeat ED visits for domestic violence after the index ED visit. RESULTS: After the initiation of the program, shelter use increased from 11% to 28% (P =.003) and shelter-based counseling increased from 1% to 15% (P <.001). There was no change in repeat police calls (25% versus 35%, P =.14), full orders of protection (9% versus 6%, P =. 58), or repeat ED visits for domestic violence (11% versus 8%, P =. 63). CONCLUSION: ED-based advocacy for domestic violence resulted in increased use of shelters and shelter-based counseling.

How often do women in the emergency department without intimate violence injuries return with such injuries?

OBJECTIVE: To determine the rate at which a group of women visiting the ED for reasons other than intimate violence return to the ED at a later time for intimate-violence-related injuries. METHODS: Retrospective cohort study of a group of women with intimate-violence-related injuries on an index visit and a matched comparison group. Return visit rates to the ED for intimate violence injuries over the next 5 years were then compared. RESULTS: The 95 women in each group were followed an average of 57 months. The return rates in the positive index case group and matched comparison group, respectively, for any reason were 74.9% vs 77.9% (p = 0.463) and for intimate violence injuries were 29.5% vs 18.9% (p = 0.118). CONCLUSION: Women in the ED without intimate violence injuries often return to the ED later with such injuries. This suggests the ED may play an important role in identifying women at risk for future intimate-violence-related injury.

Retained glass foreign bodies in wounds: predictive value of wound characteristics, patient perception, and wound exploration.

A convenience sample of 164 adult patients with 185 glass-caused wounds who presented to an emergency department (ED) and consented to a radiograph was prospectively studied. The purpose was to determine the characteristics of wounds at high risk for foreign body (FB) and the predictive value of patient FB sensation and probing wound exploration for FB retention. Retained glass was located in 28 (15%) wounds. Motor vehicle as a mechanism of injury (P=.003), head as a location (P=.035), and puncture as wound type (P=.002) were more likely to be associated with retained FBs (chi2 analysis). Patients with wounds with glass were more likely to have a positive perception of a foreign body (41%) than those with no glass (17%) (P=.005). The positive predictive value of patient perception was 31%; negative predictive value was 89%. In five cases, wound exploration was negative and subsequent radiograph was positive for FB. In one of these cases, a 4-mm glass FB was removed; in the other four, no FB was found. In conclusion, head wounds resulting from motor vehicle accidents or puncture wounds are more likely to harbor retained glass FBs. Patients with glass FB in wounds are more likely to have a positive perception of FB; however, a positive perception has a low predictive value of glass FB. In this series, a negative wound exploration made the presence of retained FB greater than 2 mm less likely but did not rule out the presence of retained glass.

Male victims of domestic violence and their history of perpetrating violence.

OBJECTIVE: To determine whether male victims of domestic violence have similar rates of violence perpetration compared with men evaluated in the ED with other causes of injury. METHODS: Case-control retrospective ED record review with linkage to police department records. Cases were identified by ICD code N-code 995.81 (adult maltreatment syndrome) over a 4-year period (January 1, 1991, to December 31, 1994) at one urban trauma center. Medical records were reviewed to confirm that the assailant was an intimate female partner. Controls were identified by E-codes 880-888 (unintentional falls) and matched by age, race, and date of visit. All names were linked to police department record information regarding arrests for domestic violence perpetration, nonaggravated assaults, aggravated assaults, firearms violations, and driving under the influence of alcohol (DUI). This information was reported without patient identifiers. Comparisons between cases and controls were made with chi2 analysis. RESULTS: Forty-five cases and 45 controls were identified. The cases were injured by unarmed fights, E960 (31%); cuttings, E966 (33%); blunt objects, E968.2 (31%); and bites, E968.8 (5%). Median age (interquartile range) for cases was 32 (25.75, 38.25) years and for controls was 31 (25, 36.5) years. Median follow-up (interquartile range) of police records after ED visit was 45 (37, 50) months for cases and 45 (36.75, 51) months for controls. Fifty-one percent of the cases had arrests for domestic violence perpetration vs 22.2% of the controls (p=0.009). Forty-four percent of the cases had been arrested for nonaggravated assaults vs 20.0% of the controls (p=0.024). There was no statistical difference between the cases and controls in arrests for aggravated assaults (13.3% vs 4.4%), firearm violations (22.2% vs 17.8%), or DUIs (35.6% vs 20%). CONCLUSION: Men who present to the ED with injuries inflicted by their female partners have a high rate of domestic violence perpetration. This information calls into question whether many male "victims" of domestic violence are injured in self-defense by the female "victim." Also, injury by a female partner may be a useful indicator to identify batterers, so they can be referred by appropriate resources.

Opioid toxicity recurrence after an initial response to naloxone.

OBJECTIVE: To determine the frequency and potential predictors of opioid toxicity recurrence after a response to naloxone in adult Emergency Department patients. METHODS: A retrospective case-control study of naloxone-treated patients with opioid toxicity over an 8-year period. Both the patient response to naloxone and recurrence of opioid toxicity was determined by an expert Delphi Panel. The frequency of opioid toxicity recurrence was compared by the duration of opioid effect, the route of opioid exposure, and the presence of other CNS depressant drugs. RESULTS: Ninety of 221 (41%) cases with a discharge diagnosis of opioid toxicity were treated with naloxone; six patients were excluded because of a lack of toxicity. There was a response to naloxone in 50% of the 84 cases, and recurrence of toxicity in 31% (95% CI 17-45%) of naloxone responders. The most common opioids were codeine, heroin, propoxyphene, and oxycodone/hydrocodone. Recurrence of toxicity was more common with long-acting opioids (p = 0.04), and was not associated with the route of opioid exposure (p = 0.42), or presence of ethanol and other CNS depressants (p > or = 0.87). CONCLUSION: Opioid toxicity recurrence after a response to naloxone occurred in approximately 1/3 of adult Emergency Department opioid overdose cases. Recurrence was more common with long-acting opioids and was not associated with the route of opioid exposure. Other clinically useful predictors of toxicity recurrence were not identified.

Battered women: where they go for help.

OBJECTIVE: Assistance must be available to abused women where they seek help. This study identified victims of partner abuse and asked them to indicate where they sought help when battered. The characteristics of acute battering incidents were also investigated. METHODS: Consecutive women, ages 19 to 65, were recruited when they came to 10 emergency departments in two cities. Women were excluded if the following criteria existed: a language barrier, serious illness, or inability to separate subjects from accompanying persons. RESULTS: Of 4448 women who completed the questionnaire, 37% acknowledged physical abuse by a partner at some time; 10% reported a present battering relationship; and 4% said their current visit to the emergency department was for abuse by an intimate partner. In 70% of surveys, the battering person was a boyfriend or ex-boyfriend. Weapons used were items near at hand. The three most common helping resources, in decreasing frequency of use, were family and friends, police, and the emergency department. DISCUSSION: Resources to provide help must be available where women seek care when they are abused. Abuse among women who come to emergency departments is common, and emergency departments are the third highest resource cited by abused women. Emergency nurses should be prepared to identify and assist abused women.

Nonbattering presentations to the ED of women in physically abusive relationships.

To determine which diagnoses in the emergency department (ED), apart from battering injuries, were more common among women who were living in physically abusive relationships than among women who were not, a study was conducted in 10 hospital-based EDs in two cities serving inner city, urban, and suburban populations. A total of 9,057 women between the ages of 19 and 65 years presenting to the EDs were eligible for the study. Medical records were reviewed, and a written questionnaire was used. The questionnaire was completed by 4,501 (73% of those asked, 59% of those eligible, and 50% of those presenting). Two hundred sixty-six (5.9%) were currently in a physically abusive relationship but not in the ED for battering injuries, and 3,969 (88.2%) were not currently in a physically abusive relationship. An additional 266 (5.9%) were positive, probable, or suggestive for battering injuries and excluded from diagnosis comparisons. Women in physically abusive relationships were more likely to be diagnosed with urinary tract infections, neck pain, vaginitis, foot wound, suicide attempt, and finger fracture. However, these represented only 19.8% of diagnoses in this group. The use of this knowledge alone to predict the presence of intimate violence in individual patients in the ED will not identify the majority of women at risk. These results suggest the use of routine inquiry for abuse in all women.

Missouri's emergency department E-code data reporting: a new level of data resource for injury prevention and control.

This article describes the results of the first statewide external cause of injury (E-code) reporting system that includes emergency department (ED) visits. The results indicate that for every injury-related death, there are 20 hospitalizations and 174 ED visits. Although firearms and motor vehicle crashes were the leading causes of injury-related deaths, falls and motor vehicle crashes were the leading causes of ED visits. An analysis of injuries in one metropolitan statistical area in the state demonstrates similarities and differences from the statewide results. The statewide reporting of cause of injury information in ED visits provides valuable information for injury control efforts.

Measuring response intervals in a system with a 911 primary and an emergency medical services secondary public safety answering point.

STUDY OBJECTIVE: Measurement of interval data is important in the accurate recording of events that occur in an emergency medical services system. Measurement of intervals should be a simple task. However, when two separate clocks are needed to record the beginning and end of an interval, accurate measurement may be difficult. We sought to accurately measure the 911 call receipt-to-vehicle departure and 911 calls receipt-to-patient access intervals in a system with primary and secondary public safety answering points (PSAPs). METHODS: We conducted a descriptive study between January 1 and July 31, 1993. All 911 calls beginning at the primary PSAP, transferred to the EMS secondary PSAP, and ending with patient access times were eligible. Clock-synchronization errors and unavailability of 911 time logs were the criteria for exclusion. We measured the 911 call receipt-to-vehicle departure interval by adding the primary-PSAP and the EMS secondary-PSAP call-processing intervals. The 911 call receipt-to-patient access interval was the absolute difference between the time when the 911 primary-PSAP phone range and the time of patient access recorded by EMS personnel. RESULTS: The data were best described with median and interquartile ranges (IQRs). We found 1,945 calls that met inclusion criteria. Of these, 270 were deleted because of clock errors and 616 for time log unavailability, yielding 1,059 calls for interval determinations. The median 911 call receipt-to-vehicle departure interval was 1.7 minutes (IQR, 1.2 to 2.2 minutes). The median 911 call receipt-to-patient access interval was 8.2 minutes (IQR, 6.4 to 10.5 minutes). CONCLUSION: The 911 call receipt-to-vehicle departure and 911 call receipt-to-patient access intervals can be accurately measured in a system with two separate PSAP computer-aided dispatch clocks. These intervals are variable and often lengthy.

The use of pegorgotein in the treatment of frostbite.

Free oxygen radicals have been postulated to be an important mediator of injury in frostbite. A long-acting version of the endogenous scavenger enzyme, superoxide dismutase, has been created by conjugating it with polyethylene glycol (pegorgotein, formerly known as PEG-SOD). This study evaluated the efficacy of pegorgotein on frostbite tissue survival when administered prior to rewarming. In a prospective study, two groups of nine rabbits received a standardized frostbite injury using a modified Weatherley-White model. A control group received no pharmacologic therapy; the treatment group received 10,000 IU/kg pegorgotein intravenously immediately postinjury. Healing was followed until a clear line of demarcation was apparent (10 days). The percentage of viable ear surface remaining at the end of the study was measured and used to compare the effectiveness of treatment. Student's t-test was used to determine statistical significance. The study was designed to have an 80% ability to detect a 35% difference in tissue survival. No significant difference in frostbite injury (p = 0.967) was observed between the control and treatment groups. The treatment group showed a 9.3 +/- 15.5% tissue survival, whereas the control group had 9.6 +/- 14.5% tissue survival. These results indicate no significant treatment effect for pegorgotein on tissue survival in a rabbit frostbite injury model when administered immediately postinjury.

Battered women: injury locations and types.

STUDY OBJECTIVE: To characterize injuries to battered women by comparing their location, type, and severity with those of injuries to women resulting from other mechanisms. METHODS: Cross-sectional study of 9,057 women between the ages of 19 and 65 years who presented for any reason to the emergency departments of 10 hospitals serving inner-city, urban, and suburban populations. RESULTS: A total of 280 injured, battered women were identified during the study period. About 3.1% (95% confidence interval [Cl]. 2.7% to 3.5%) of all women seen in the ED, and 11.2% [95% Cl, 10.0% to 12.4%) of injured women with known mechanisms of injury, were determined to be positive for battering. Battered women were more likely to be injured in the head, face, neck, thorax, and abdomen (P < .001) than were women injured by other mechanisms. Twelve specific injury types were identified that occurred more frequently in battered women. CONCLUSION: Although battered women experience certain injury types more frequently than women injured by other mechanisms, the low positive predictive value of these injuries supports the use of universal screening for domestic violence in all injured women.

Fatal motor vehicle crashes: variations of crash characteristics within rural regions of different population densities.

OBJECTIVE: While it is known that motor vehicle crash (MVC) fatality rates are inversely related to population density, there has been no description of which crash variables are related to population density. The purpose of this study was to describe crash characteristics of fatal MVCs and to determine which crash characteristics are related to population density. DESIGN: This is a retrospective review of fatal accident reporting system (FARS) records. They represent four different population density regions over a 5-year period in a four-state midwest region. RESULTS: There were 10,932 people in 6,318 vehicles who were involved in 4,970 fatalities. Occupant fatality rates per 100,000 persons were inversely related to population density. The variables related to lower population density were more light and heavy truck types, more frequent alcohol use and higher levels of intoxication, more frequent crashes that are noncollisions on less heavily traveled roads, more frequent crashes on gravel surface types, more frequent occupant ejection, and delayed medical care. CONCLUSION: Rural areas are not homogenous in terms of fatal MVC crash characteristics. By analyzing fatal MVC crash characteristics in regions with different population densities, many crash variables were found to be related to population density. By understanding which characteristics about fatal MVCs are related to population densities, different interventions could be targeted to different rural populations.

An emergency medicine approach to violence throughout the life cycle. SAEM Public Health and Education Committee.

This document by the SAEM Public Health and Education Committee outlines the public health impact of interpersonal violence as it pertains to acute emergency care. This paper provides an overview of violence through the life cycle (i.e., child abuse, youth violence, intimate violence, and elderly abuse). It also makes specific recommendations regarding the role emergency physicians can play in reducing violence through medical education, research, surveillance, public education, advocacy, and clinical practice.