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B B Hackman

Publications and source records attributed to B B Hackman.

18 recordsLinked to original sources
PubMed1996

Injuries due to firearms in three cities.

BACKGROUND: To describe the incidence and outcome of injuries due to firearms, we conducted a population-based study of fatal and nonfatal gunshot wounds in three cities: Memphis, Tennessee; Seattle; and Galveston, Texas. METHODS: Records of the police, medical examiners, ambulance crews, and hospital emergency departments and hospital admissions were monitored to identify all injuries caused by firearms that were severe enough to prompt emergency medical treatment. These records were linked to generate a complete picture of each event. Census data were used to calculate rates of injury for various population groups. RESULTS: A total of 1915 cases of injury due to firearms were identified between November 16, 1992, and May 15, 1994. The crude rate of firearm injury per 100,000 person-years was 222.6 in Memphis, 143.6 in Galveston, and 54.1 in Seattle. Approximately 88 percent of the injuries were incurred during confirmed or probable assaults; 7 percent were sustained in the course of suicide or attempted suicide; unintentional injuries accounted for 4 percent of the cases. Handguns were used in 88 percent of the cases in which the type of weapon was recorded. Five percent of the 1677 victims who were brought to a hospital emergency department could not be resuscitated; 53 percent were hospitalized, and 42 percent were treated and released. Ninety-seven percent of the deaths occurred within 24 hours of the injury. Emergency department and inpatient charges exceeded $16.5 million. CONCLUSIONS: Injuries due to firearms, most involving handguns, are a major cause of morbidity and mortality in U.S. urban areas. The incidence varies greatly from city to city.

Adolescent↗
PubMed1995

Three-rescuer CPR: the method of choice for firefighter CPR?

STUDY OBJECTIVE: To compare the quality of CPR provided by firefighters performing three-rescuer CPR with that achieved by firefighters trained to provide standard two-rescuer CPR. DESIGN: Eight months after training a large number of firefighters to perform three-rescuer CPR, we used a quasi-experimental design to compare the performance of a randomly selected subset of these companies to that achieved by a control group of engine companies that received refresher training in standard two-rescuer CPR. Both groups used bag-valve masks to provide rescue ventilations. Testing was conducted on a no-notice basis with a recording mannequin. Key actions were scored by an experienced observer using explicit pass-fail criteria. Mannequin-generated strip charts were used to calculate the rate and depth of chest compressions and the ventilatory rate, volume, and minute ventilation in a blinded manner. SETTING: Fire stations of the Memphis Fire Department. The department is the sole provider of first-responder emergency care to the citizens of Memphis, Tennessee (population, 610,000). RESULTS: Three-rescuer teams delivered a mean minute ventilation substantially greater than that produced by two-rescuer teams (7.7 +/- 5.3 L versus 4.9 +/- 4.2 L, P < .001). Intergroup differences in the mean depth of chest compressions were less marked, but they were still significant (17.2 +/- 8.3 mm of recorder-needle deflection versus 13.7 +/- 7.0 mm, P < .001). CONCLUSION: Three rescuers can produce better CPR than two when a bag-valve-mask device is used. The technique is easily learned and readily retained.

Cardiopulmonary Resuscitation↗
PubMed1994

Do blacks get bystander cardiopulmonary resuscitation as often as whites?

STUDY OBJECTIVE: To determine whether there is an association between the race of a victim of out-of-hospital cardiac arrest and the provision of bystander-initiated CPR. DESIGN: Record review of 1,068 consecutive cases of nontraumatic out-of-hospital cardiac arrest. SETTING: Memphis, Tennessee, a city of more than 600,000 with roughly equal numbers of white and black residents. PARTICIPANTS: Every adult who was seen by municipal emergency medical services personnel for nontraumatic cardiac arrest between March 1, 1989, and June 5, 1992. INTERVENTION: None. RESULTS: Although black and white cardiac arrest victims were similar in many respects, black victims received bystander CPR substantially less frequently than whites (9.8% versus 21.4%; odds ratio, 0.46; 95% confidence interval, 0.34 to 0.61). This difference was slightly more pronounced when the victim collapsed in a public place. In addition to race of the victim, location of the arrest outside the home and having the arrest witnessed were independent determinants of whether a victim was given bystander CPR. Multiple logistic regression analysis showed that the effect of race was independent of the other variables studied. CONCLUSION: Black victims of out-of-hospital cardiac arrest receive bystander CPR less frequently than white victims. Targeted training programs may be needed to improve the rates of bystander CPR among certain groups.

Black or African American↗
PubMed1993

Impact of first-responder defibrillation in an urban emergency medical services system.

OBJECTIVE: To evaluate the impact of adding first-responder defibrillation by fire-fighters to an existing advanced life-support emergency medical services system. DESIGN: Nonrandomized, controlled clinical trial with periodic crossover. SETTING: Memphis, Tenn, a city of 610,337 people, which is served by a fire department-based emergency medical services system. All city ambulances provide advanced life support. PATIENTS: Adult victims of out-of-hospital cardiac arrest due to heart disease. INTERVENTION: Twenty of 40 participating engine companies were equipped with an automated external defibrillator and ordered to apply it immediately in all cases of cardiac arrest. The other 20 companies were ordered to start cardiopulmonary resuscitation (CPR) immediately and wait for paramedics to arrive. Every 75 days, group roles were reversed. Care otherwise proceeded according to 1986 American Heart Association guidelines. MAIN OUTCOME MEASURES: Return of spontaneous circulation in the field, survival to hospital admission, survival to hospital discharge, and neurological status at discharge. RESULTS: During the 39-month study interval, 879 patients were treated by a project engine company. Four hundred thirty-one (49%) of these were found in ventricular fibrillation. Bystander CPR was started in only 12% of cases. Overall, firefighters reached the scene a mean of 2.5 minutes faster than simultaneously dispatched paramedics. Although our automated external defibrillators proved to be reliable and efficacious for terminating ventricular fibrillation and pulseless ventricular tachycardia, patients treated by an automated external defibrillator-equipped engine company were no more likely than CPR-treated controls to be resuscitated (32% vs 34%, respectively), to survive to hospital admission (31% vs 29%), or to survive to hospital discharge (14% vs 10%). Neurological outcomes were also similar in the two treatment groups. CONCLUSIONS: In a fast-response, urban emergency medical services system served by paramedics, the impact of adding first-responder defibrillation appears to be small. Early defibrillation alone cannot overcome low community rates of bystander CPR. Careful attention to every link in the "chain of survival" is needed to achieve optimal rates of survival after cardiac arrest.

Aged↗
PubMed1993

Gun ownership as a risk factor for homicide in the home.

BACKGROUND: It is unknown whether keeping a firearm in the home confers protection against crime or, instead, increases the risk of violent crime in the home. To study risk factors for homicide in the home, we identified homicides occurring in the homes of victims in three metropolitan counties. METHODS: After each homicide, we obtained data from the police or medical examiner and interviewed a proxy for the victim. The proxies' answers were compared with those of control subjects who were matched to the victims according to neighborhood, sex, race, and age range. Crude and adjusted odds ratios were calculated with matched-pairs methods. RESULTS: During the study period, 1860 homicides occurred in the three counties, 444 of them (23.9 percent) in the home of the victim. After excluding 24 cases for various reasons, we interviewed proxy respondents for 93 percent of the victims. Controls were identified for 99 percent of these, yielding 388 matched pairs. As compared with the controls, the victims more often lived alone or rented their residence. Also, case households more commonly contained an illicit-drug user, a person with prior arrests, or someone who had been hit or hurt in a fight in the home. After controlling for these characteristics, we found that keeping a gun in the home was strongly and independently associated with an increased risk of homicide (adjusted odds ratio, 2.7; 95 percent confidence interval, 1.6 to 4.4). Virtually all of this risk involved homicide by a family member or intimate acquaintance. CONCLUSIONS: The use of illicit drugs and a history of physical fights in the home are important risk factors for homicide in the home. Rather than confer protection, guns kept in the home are associated with an increase in the risk of homicide by a family member or intimate acquaintance.

Adolescent↗
PubMed1993

Engineering excellence: options to enhance firefighter compliance with standing orders for first-responder defibrillation.

STUDY OBJECTIVE: To assess the quality of care delivered during first-responder defibrillation and to determine the potential efficacy of modifying existing automated external defibrillator designs to improve first-responder performance. DESIGN: Prospective case series. SETTING: An urban emergency medical services system providing first-responder defibrillation and paramedic care. TYPE OF PARTICIPANTS: Firefighters who completed a four-hour (two-session) course in automated external defibrillator operation. METHODS: Heartstart 2000 defibrillators (Laerdal Medical Corp, Armonk, New York) were used in 241 consecutive resuscitation attempts. Written reports and memory module printouts were abstracted to assess firefighter performance of 11 critical actions. The firefighter's response to each opportunity to perform a critical action was scored using explicit pass/fail criteria. RESULTS: Records of 235 automated external defibrillator uses (97.5%) were submitted for analysis. Firefighters shocked within 15 seconds of a "shock indicated" message in 95% of opportunities and reanalyzed the rhythm within 90 seconds of the third consecutive shock (ie, after one minute of CPR) in 80% of cases. However, firefighters reanalyzed the patient's rhythm too soon in 75% of cases, thereby interfering with recommended intervals of CPR. Firefighters failed to reanalyze the patient's rhythm after device-initiated "check patient" prompts 62% of the time. Memory modules were left in the automated external defibrillator during practice sessions in 64 cases, decreasing available memory to monitor automated external defibrillator use in the field. Three instances of failure to withhold CPR during rhythm analysis resulted in a single inappropriate patient shock. No firefighter was shocked inadvertently. CONCLUSION: Current device algorithms result in effective delivery of the initial three shocks. However, firefighters often fail to interpose recommended intervals of CPR between further attempts at defibrillation. Modification of existing device algorithms to provide additional visual and auditory cues may be preferable to relying on the user to recall accurately all the steps in this infrequently performed procedure.

Allied Health Personnel↗
PubMed1993

Pulmonary edema associated with pregnancy: echocardiographic insights and implications for treatment.

OBJECTIVE: To evaluate the role of echocardiography in determining the cause of pulmonary edema in pregnancy and the impact this information has on management. METHODS: We studied prospectively 45 pregnant or recently postpartum women admitted to an obstetric intensive care unit with pulmonary edema during a 6-year period. Between 1 and 4 days after the onset of pulmonary edema, two-dimensional and M-mode echocardiography was performed, as was continuous, pulsed, and color Doppler echocardiography. The clinical diagnosis obtained from history, physical examination, chest radiograph, and laboratory data was compared with the echocardiographic diagnosis. RESULTS: Three therapeutically and prognostically distinct groups were identified by echocardiography: 1) those with decreased systolic function (N = 19), 2) those with normal systolic function but increased left ventricular mass and presumed diastolic dysfunction (N = 17), and 3) those with normal hearts (N = 9). During the study period, two patients with systolic dysfunction died and one underwent cardiac transplantation. Patients with systolic dysfunction required short- and long-term treatment with digoxin, diuretics, and angiotensin-converting enzyme inhibitors. Those with diastolic dysfunction received diuretics and long-term antihypertensive therapy. Women with normal hearts required acute therapy only. In 21 patients (47%), echocardiography demonstrated clinically unsuspected findings, which altered the long-term management in 16. CONCLUSION: Because clinical and roentgenographic findings do not accurately differentiate patients with respect to the presence and type of cardiac dysfunction, and because these subgroups differ with respect to treatment and probably prognosis, we recommend echocardiography to evaluate all pregnant women with pulmonary edema.

Adult↗
PubMed1992

Suicide in the home in relation to gun ownership.

BACKGROUND: It has been suggested that limiting access to firearms could prevent many suicides, but this belief is controversial. To assess the strength of the association between the availability of firearms and suicide, we studied all suicides that took place in the homes of victims in Shelby County, Tennessee, and King County, Washington, over a 32-month period. METHODS: For each suicide victim (case subject), we obtained data from police or the medical examiner and interviewed a proxy. Their answers were compared with those of control subjects from the same neighborhood, matched with the victim according to sex, race, and age range. Crude and adjusted odds ratios were calculated with matched-pairs methods. RESULTS: During the study period, 803 suicides occurred in the two counties, 565 of which (70 percent) took place in the home of the victim. Fifty-eight percent (326) of these suicides were committed with a firearm. After excluding 11 case subjects for various reasons, we were able to interview 80 percent (442) of the proxies for the case subjects. Matching controls were identified for 99 percent of these subjects, producing 438 matched pairs. Univariate analyses revealed that the case subjects were more likely than the controls to have lived alone, taken prescribed psychotropic medication, been arrested, abused drugs or alcohol, or not graduated from high school. After we controlled for these characteristics through conditional logistic regression, the presence of one or more guns in the home was found to be associated with an increased risk of suicide (adjusted odds ratio, 4.8; 95 percent confidence interval, 2.7 to 8.5). CONCLUSIONS: Ready availability of firearms is associated with an increased risk of suicide in the home. Owners of firearms should weigh their reasons for keeping a gun in the home against the possibility that it might someday be used in a suicide.

Adult↗
PubMed1992

Comparative effects of fenoldopam mesylate and nitroprusside on left ventricular performance in severe systemic hypertension.

To compare the effects of fenoldopam (n = 15), a selective dopamine-1 agonist, and nitroprusside (n = 14) on left ventricular (LV) function in severely hypertensive subjects (diastolic blood pressure (BP) greater than 120 mm Hg), both agents were infused to reduce diastolic BP by 40 mm Hg (or less than 110 mm Hg). Indexes of LV systolic and diastolic functions were obtained using gated radionuclide angiography before the initiation of treatment and after targeted BP was achieved. Both fenoldopam and nitroprusside effectively reduced systolic and diastolic BP to target levels. Changes in heart rate, peak filling rate and relative end-diastolic volume were similar with both agents. Baseline ejection fraction increased after infusion of both drugs. The magnitude of the increase in ejection fraction was far greater with fenoldopam than with nitroprusside (+22% vs +8%; p = 0.04), despite a lesser reduction in systolic BP (-12 vs -22%, p = 0.002). Furthermore, the reduction in relative end-systolic volume (-35 vs -20%; p = 0.04), and increase in the ratio of peak systolic pressure to relative end-systolic volume (+43 vs +6%; p = 0.007) were greater after fenoldopam than after nitroprusside. The greater increment in parameters of LV systolic function produced by fenoldopam than by nitroprusside suggests an effect on LV performance that is independent of afterload reduction.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1991

Impact of portable pulse oximetry on arterial blood gas test ordering in an urban emergency department.

STUDY OBJECTIVE: To determine the impact of portable pulse oximetry on physician use of arterial blood gas tests (ABGs) in an urban emergency department. DESIGN: Prospective, controlled clinical trial. SETTING: The ED of the Regional Medical Center at Memphis, a publicly subsidized, 450-bed, acute care hospital staffed by residents and faculty of the University of Tennessee, Memphis. TYPE OF PARTICIPANTS: Rotating housestaff treating adult ED patients with a wide variety of medical and surgical problems. INTERVENTION: Introduction of a portable pulse oximeter for noninvasive measurement of blood oxygenation. MEASUREMENTS: Rates of ABG test ordering, housestaff reason(s) for ordering an ABG, and the incidence of adverse clinical outcomes before and after introduction of portable pulse oximetry. MAIN RESULTS: A total of 20,120 patient visits occurred during the four-month study. Before oximeter introduction, emergency physicians ordered 699 ABGs, 63% of which were indicated by explicit criteria. After oximeter introduction, 440 ABGs were ordered (a 37% decrease). Almost all of this decrease was due to fewer ABGs ordered to assess oxygenation (260 before vs 75 after; chi 2, P less than .001). These reductions were not explained by differences in total patient visits or case mix. Physicians decreased ordering of indicated ABGs by almost as great an extent as they reduced ordering of unindicated tests, suggesting they did not consistently distinguish between the two. However, decreased testing did not result in any serious adverse outcomes, defined as unanticipated respiratory or cardiac arrest in the ED, unanticipated arrest on the floor within 24 hours of admission, or death within two days of hospital discharge. CONCLUSION: Portable pulse oximetry can provide a simple, noninvasive way to determine oxygen saturation in the ED. Routine use of portable pulse oximetry may substantially reduce rates of ABG testing and associated patient charges without adversely affecting the quality of emergency care.

Adult↗
PubMed1991

Emergency departments and crowding in United States teaching hospitals.

STUDY OBJECTIVES: To assess the extent and distribution of hospital and emergency department crowding nationally. DESIGN: The research design consisted of a mailed questionnaire disseminated in the fall of 1988 to the member institutions of the National Association of Public Hospitals (NAPH) and the Council of Teaching Hospitals (COTH). TYPE OF PARTICIPANTS: Study participants included hospital administrators and ED directors from 239 of the non-Veterans Administration, general acute care, US members of COTH and NAPH. MEASUREMENTS: Key measures of hospital and ED crowding including mean ED holding times for floor and ICU beds. MAIN RESULTS: Three fourths of responding hospitals reported increases in ED visits over the preceding three years. Mean ED holding times for admitted patients were 3.5 hours (median, 2.0 hours) for a floor bed and 2.9 hours (median, 1.5 hours) for an ICU bed. Half of all hospitals noted maximum waits for floor and ICU beds of ten hours or more and seven hours or more, respectively. Measures taken by hospitals to manage crowding during August 1988 included restricting access to some types of patients (mean, 3.6 days), actively transferring patients to other hospitals (mean, 2.2 days), transfer refusal (mean, 2.8 days), and total ambulance diversion (mean, 1.6 days). CONCLUSIONS: Our study strongly suggests that ED crowding is not an isolated phenomenon; ED crowding and its attendant problems appear to affect hospitals with similar adverse effects regardless of ownership. Although our results suggest that ED crowding is concentrated in metropolitan areas and in a smaller subset of hospitals, we found instances of crowding among hospitals nationwide.

Bed Occupancy↗
PubMed1990

Patient 'dumping' post-COBRA.

To gauge the impact of the new federal patient transfer provisions following the federal Combined Budget Reconciliation Act of 1985 (COBRA), we monitored all emergency interhospital transfers to a public hospital emergency department in the Memphis, Tennessee area during three identical time periods: June 1 to August 31 of 1986, 1987, and 1988. A high number of transfers in the summer of 1986 diminished only slightly in summer 1987 (following implementation of COBRA). Far greater reductions occurred in summer 1988, when overcrowding forced our hospital to refuse most transfers. In contrast to changes in hospital policy, COBRA alone had little effect in this area.

Emergency Service, Hospital↗
PubMed1989

Dispatcher-assisted cardiopulmonary resuscitation. Validation of efficacy.

Dispatcher-delivered telephone instruction in cardiopulmonary resuscitation (CPR) has been proposed to increase rates of bystander CPR in cases of out-of-hospital cardiac arrest. We tested the efficacy of a previously developed CPR message using a recording mannikin in a high stress, simulated cardiac arrest scenario. Community volunteers were unaware they would perform CPR until immediately before each trial. Performance of volunteers without prior CPR training (group A, n = 65) who received telephone instruction was compared with that of previously trained volunteers (group B, n = 43) who received the same message. Performances of both groups were also compared with a third group (group C, n = 43) composed of previously trained volunteers who did not receive the message. Quality of CPR was graded by three CPR instructors using explicit criteria. Printout strips from the recording mannikins were also analyzed. Evaluators were unaware of the training status of volunteers. The three groups were of comparable sex, race, and educational level, but group C was significantly younger than groups A and B (31.7 vs. 37.7 years, p less than 0.001). Because of the time required for telephone instruction, groups A and B started chest compressions a mean of 4.0 minutes after collapse compared with 1.2 minutes for group C (p less than 0.0001). We found that the previously untrained volunteers of group A performed CPR of an overall quality comparable to that performed by previously trained members of group C. Group A performed chest compressions significantly better than group C (p less than 0.02) but had greater problems performing effective ventilations.(ABSTRACT TRUNCATED AT 250 WORDS)

Emergencies↗
PubMed1988

In-hospital resuscitation following unsuccessful prehospital advanced cardiac life support: 'heroic efforts' or an exercise in futility?

From our emergency department logbook we identified 281 consecutive patients transported to the Regional Medical Center at Memphis following failed prehospital advanced cardiac life support (ACLS). Medical records were obtained for 240 cases (85.4%). Initial cardiac rhythms in the ED included ventricular fibrillation or pulseless ventricular tachycardia (29%), electromechanical dissociation (18%), and asystole (51%). Thirty-two patients (13.3%) were successfully resuscitated in the ED, but only four (1.7%) survived to hospital discharge. Two patients had good neurologic outcomes; both degenerated to cardiac arrest shortly prior to arrival in the ED. The remaining two survivors were discharged to nursing homes with severe neurologic deficits. Of the 41 cases for whom no medical records could be found, 39 were noted in our logbook to have died in the ED. No record of subsequent hospital admission could be found for the other two. Both are presumed to have died. Failure to respond to prehospital ACLS predicts nonsurvival and may warrant cessation of efforts in the field. Future programs and research efforts in the management of out-of-hospital cardiac arrest should be focused on optimal provision of prehospital care prior to the onset of irreversible deterioration.

Emergencies↗
PubMed1988

Emergency department patient 'dumping': an analysis of interhospital transfers to the Regional Medical Center at Memphis, Tennessee.

To study the extent and nature of transfers of emergency department (ED) patients because of inability to pay, we audited all telephone requests and actual patient transfers from private hospital EDs and their affiliated free-standing emergency centers to the ED of the Regional Medical Center at Memphis (the Med), a publicly subsidized hospital, between June 1 and August 31, 1986. Transfers to the Med's "special care" centers were assumed to represent tertiary care referrals and were excluded. During the 92-day study interval, ED physicians at the Med handled 190 telephone requests for transfer. Requesting physicians explicitly identified "no money" or "no insurance" as the primary reason for transfer in 89 per cent of 164 cases in which these data were recorded. Thirty-seven per cent of requests were refused; half were too unstable or required an intensive care unit (ICU) bed when none were available. One hundred forty-six transfers (55 per cent) arrived without prior telephone authorization, most by private automobile. Almost all transferred patients (91 per cent) were sent for primarily economic reasons. One out of four was found to be unstable on arrival by explicit clinical criteria. Eighty-two patients transferred for economic reasons (34 per cent) required emergency hospitalization and accounted for 564 bed days during a period of extreme inpatient crowding. Three patients died prior to discharge. Two had been transferred for primarily economic reasons.

Emergency Service, Hospital↗
PubMedDate not supplied

Predicting the outcome of unsuccessful prehospital advanced cardiac life support.

OBJECTIVE: To determine if failure to achieve return of spontaneous circulation following prehospital advanced cardiac life support (ACLS) warrants termination of efforts at the scene. DESIGN: Retrospective case series. SETTING: Memphis, Tenn, a city of 610337 people that is served by a fire department-based emergency medical service system. All city ambulances provide ACLS. PATIENTS: Adult victims of out-of-hospital cardiac arrest due to heart disease. INTERVENTION: All patients received prehospital ACLS according to the 1986 American Heart Association guidelines. Following prehospital ACLS, all patients were transported to the nearest hospital emergency department whether or not a pulse was restored in the field. MAIN OUTCOME MEASURES: Survival to hospital admission, survival to hospital discharge, and neurological status at discharge. RESULTS: Over the 39-month study interval, the Memphis Fire Department treated 1068 victims of out-of-hospital cardiac arrest. Three hundred ten of these (29%) had return of spontaneous circulation prior to transport for some period. The remaining 758 patients (71%) never regained a pulse and were transported with ongoing cardiopulmonary resuscitation. Patients who had return of spontaneous circulation prior to transport were more likely to be admitted (69% vs 7.0%) and far more likely to be discharged alive (26.5% vs 0.4%) than patients who failed to respond to prehospital ACLS. Three patients who survived to hospital discharge despite failure to achieve return of spontaneous circulation prior to emergency medical service transport sustained their cardiac arrest after paramedic arrival. All three were discharged with moderate to severe cerebral disability. CONCLUSION: Rapid transport of adults who fail to respond to an adequate trial of prehospital ACLS does not result in meaningful rates of survival. In such cases, on-line emergency medical service physicians should authorize paramedics to cease efforts in the field.

Aged↗