Identification of a novel substitution in the constant region of a gene coding for an amyloidogenic kappa1 light chain

Current concepts regarding the association between immunoglobulin (Ig) light chain structure and AL amyloidosis (AL) emphasize Ig variable region amino acid substitutions because the majority of light chain amyloid fibrils that have been sequenced contain amino termini of the variable region with only small amounts of the constant region. In this report, we describe a patient with rapidly progressive AL whose amyloid deposits contained primarily monoclonal kappa light chain constant region fragments. We sequenced and analyzed this AL protein, determining that it was an O18-O8 kappa1 variant and that the constant region possessed an unusual Ser-->Asn substitution at position 177. Using pre-mortem bone marrow cells, we cloned and sequenced the cDNA for this AL protein (HCAK1) and, using DNA from post-mortem somatic tissue, we cloned and sequenced the patient's kappa germline O18-O8 donor and kappa constant region (Ckappa) gene segments. The cDNA that coded for HCAK1 contained a variable region that was derived from O18-O8, showing 96.1% homology to germline, and a Ckappa that had a nucleotide substitution (AGC to AAC), resulting in the 177Ser-->Asn replacement. Two Ckappa genes were cloned from somatic tissue DNA, one identical to a known Ckappa sequence and another containing this substitution which likely is a new Ckappa allotype. Our findings indicate that further investigation is warranted into the contributions genetic polymorphisms and light chain constant regions may make to amyloidogenesis.

Risk factors for hearing loss from meningitis in children: the Children's Hospital experience

OBJECTIVES

To identify statistically significant risk factors for hearing loss in children with meningitis, determine the overall incidence of hearing loss in a large group of children with confirmed meningitis, and quantify the percentage of children with progressive or fluctuating hearing loss after meningitis.

DESIGN

Retrospective analysis.

PATIENTS AND OTHER PARTICIPANTS

Four hundred thirty-two children admitted to the Children's Hospital, Birmingham, Ala, from January 1, 1985, to December 31, 1995, with the diagnosis of meningitis.

RESULTS

Of 432 children with meningitis, 59 (13.7%) had the development of hearing loss. Of these 59 children, 46 (78.0%) had stable sensorineural hearing loss and 13 (22.0%) had either progressive or fluctuating hearing loss. Of the variables examined using multiple logistic regression backward-elimination modeling, only 5 appeared to be significantly associated with the development of hearing loss: computed tomographic scan evidence of increased intracranial pressure (estimated odds ratio [OR] = 2.3), male sex (OR= 1.9), the common logarithm of glucose levels in the cerebrospinal fluid (OR = 0.58), Streptococcus pneumoniae as the causative organism (OR= 2.1), and the presence of nuchal rigidity (OR = 1.9). In the children with progressive hearing loss, the time for progression varied from 3 months to 4 years before hearing stabilized.

CONCLUSIONS

In this study of children diagnosed as having meningitis, hearing loss developed in 59 (13.7%). Forty-six (78.0%) of these children with hearing loss had stable auditory thresholds over time, and 13 (22.0%) exhibited deterioration or fluctuation of acuity over time. Evidence of increased intracranial pressure by computed tomographic scan, male sex, low glucose levels in the patients' cerebrospinal fluid, S pneumoniae as the causative organism, and the presence of nuchal rigidity appear to be significant predictors for future hearing loss.

Unusual distributions of body fat in AIDS patients: a review of adverse events reported to the Food and Drug Administration

This report summarizes postmarketing adverse events reported to the Food and Drug Administration (FDA) that describe unusual or abnormal fat distribution in association with anti-retroviral therapies. Reports associated will protease inhibitors were compared to those associated with non-protease inhibitor antiretroviral therapies. The Spontaneous Reporting System (SRS) and Adverse Event Reporting System (AERS) of the FDA MEDWATCH post-marketing surveillance system served as the database. Four protease inhibitors (saquinavir, indinavir, nelfinavir, and ritonavir) and seven nonprotease inhibitors (zidovudine, didanosine, zalcitabine, stavudine, lamivudine, nevirapine, and delavirdine) were searched for reports relating to: weight increase, unusual fat deposition, Cushing's syndrome, or Cushingoid appearance. Each drug was searched for its "life" from time of initial approval through a uniform database cutoff of March 18, 1998. A total of 62 cases of abnormal fat accumulation were reported in association with one or several of the four approved protease inhibitors compared to three cases reported in association with the seven non-protease inhibitor based therapies. Case descriptions varied, and included abdominal fat accumulation, breast enlargement, thick necks, buffalo humps, multiple lipomatous growths, Cushingoid features, centralized fat redistribution, and mesenteric, omental, and retroperitoneal fat accumulation. Some subjects switched or stopped their antiretroviral therapy, others underwent surgery to remove the fat, and many considered their symptoms disabling. The pathophysiologic mechanism for these events remains unclear and a causal link to a specific drug or drug class is uncertain. Patients and clinicians reporting to the MEDWATCH system, however, have clearly associated the development of abnormal body fat with protease inhibitors as opposed to other antiretroviral therapies.

Gunshot injuries to the liver: the role of selective nonoperative management

BACKGROUND

Selective nonoperative management of blunt liver injuries has become standard practice in most trauma centers. We evaluated the role of selective nonoperative management of gunshot wounds to the liver.

STUDY DESIGN

This was a retrospective review of gunshot wounds to the liver treated in a level I trauma center. Patients with peritoneal signs or hemodynamic instability were operated on without delay. Patients with a soft, nontender abdomen and no signs of heavy bleeding were selected for nonoperative management. Liver injury was diagnosed by CT scan. If peritonitis or signs of substantial internal bleeding developed, an operation was performed; otherwise the patient was discharged within a few days of admission. Analysis was restricted to the group of patients with isolated liver injuries.

RESULTS

During a 42-month period, 928 patients were admitted with abdominal gunshot injuries, 152 of whom (16%) had a liver injury. In 52 patients (34% of all liver injuries), the liver was the only injured intraabdominal organ (4 patients had associated kidney or splenic injuries that did not require surgical repair). Thirty-six of the patients (69%) with isolated liver injuries had an emergent operation because of signs of peritonitis or hemodynamic instability. The remaining 16 patients (31%) were selected for nonoperative management (3 patients had associated right kidney injury). Five patients in the observed group required delayed operation because of development of signs of peritonitis (4 patients) or abdominal compartment syndrome (1 patient). The remaining 11 patients (7% of all liver injuries or 21% of isolated liver injuries) were managed successfully without operation. One patient with delayed operation developed multiple complications from abdominal compartment syndrome, and 1 patient in the nonoperative group had a biloma, which was treated with percutaneous drainage.

CONCLUSIONS

Selected patients with isolated grades I and II gunshot wounds to the liver can be managed nonoperatively.

Microbiological status of Australian sheep meat

Two studies were undertaken to determine the microbiological status of sheep carcass meat and frozen, bulk-packed sheep meat produced in Australia. Samples were collected from 470 sheep carcasses and 415 cartons of frozen sheep trimmings over a period of approximately 12 months. Samples were collected from plants processing sheep carcasses for domestic or export markets. On carcasses, where bacterial counts were obtained, the mean of the log10 aerobic plate count (APC) was 3.92/cm2, the geometric mean of the most probable number (MPN) per square centimeter of Escherichia coli (biotype I) was 23, and the geometric mean of the coliform count was 38 MPN per cm2. A high percentage (75%) of samples was positive for E. coli (biotype I), 81% were positive for coliforms, 5.74% were positive for Salmonella spp., and 1.29% were positive for Campylobacter. Bacterial counts were higher on carcasses chilled over a weekend than on carcasses chilled for 24 h. The total number of bacteria on carcasses processed for domestic markets was similar to that on carcasses processed for export markets. E. coli O157 was not isolated from any of the 465 samples tested. Of the frozen export samples that tested positive, the mean of the log10 APC was 3.47/g, the geometric mean of the E. coli (biotype I) count was 9 MPN per g, and the geometric mean of the coliform count was 19 MPN per g. Of the frozen export samples tested, 48% were positive for E. coli (biotype I), 58% were positive for coliforms, and 6.5% were positive for Salmonella spp. E. coli O157 was recovered from 1 of 343 frozen sheep meat samples tested (0.29%). Bacterial counts were higher on samples of domestic product than on samples of export product. Results from both surveys are compared with data from similar studies conducted in other countries.

Human immunodeficiency virus and the outcome of treatment for new and recurrent pulmonary tuberculosis in African patients

The purpose of this study was to evaluate the impact of human immunodeficiency virus (HIV) infection on treatment for tuberculosis (TB). The study population comprised 28,522 black Southern African gold miners. Patients with sputum culture-positive new or recurrent pulmonary TB diagnosed in 1995 were prospectively enrolled in the cohort. Directly observed therapy (DOT) was practiced and outcomes were assessed at 6 mo after treatment was begun. There were 376 cases of TB (incidence 1,318 per 100,000), of which 190 (50%) were HIV positive and 82 (22%) had recurrent TB. There was no association between HIV status and history of previous TB or drug resistance. Neither the treatment interruption rate (2%) nor the rate at which patients transferred out of the treatment program (1.6%) were associated with HIV status. Excluding deaths, cure rates were similar for HIV-positive and HIV-negative patients (89% versus 88%), but significantly lower in those with recurrent than in those with new TB (77% versus 92%). Mortality was 0.5% in HIV-negative patients versus 13.7% in HIV-positive patients, and in the latter group was associated with CD4(+) lymphocyte depletion. Autopsy examination showed that in HIV-positive patients, early mortality was due to TB whereas late deaths were most commonly due to cryptococcal pneumonia. The study showed that a well-run TB control program can result in acceptable cure rates even in a population with a very high incidence of TB and HIV infection. Particular vigilance is needed for concurrent infections, which may contribute significantly to mortality during treatment of TB in HIV-positive patients.

Penetrating injuries to the subclavian and axillary vessels

BACKGROUND

Subclavian and axillary vascular injuries are notorious for their mortality and their difficult surgical exposure. In the present study we analyze our experience with 79 patients and describe the techniques used for surgical access to these vessels.

STUDY DESIGN

Retrospective review of the medical records of all patients with penetrating injuries to the subclavian or axillary vessels who had been admitted to 2 Los Angeles trauma centers during a 4-year, 3-month period.

RESULTS

Seventy-nine patients were admitted during the study period January 1993 to March 1997 (58 gunshot injuries, 21 other penetrating injuries). The artery was injured in 59 patients and the vein in 40 (20 patients had both arterial and venous injuries). Eighteen patients (23%) were admitted with no signs of life or were in extremis and underwent an emergency room thoracotomy without any survivors. Fifty-eight patients underwent exploration in the operating room, 1 patient with an arteriovenous subclavian fistula was successfully managed with a radiologically placed endovascular stent, and 2 patients with minimal subclavian artery injuries were managed nonoperatively. Overall mortality was 34.2%. Excluding the ER thoracotomies the overall mortality was 14.8%. The mortality for isolated arterial injuries was 20.5%, for isolated venous injuries 50%, and for both vessels 45.0%. The mortality in venous injuries was significantly higher than in arterial injuries (p < 0.05). The standard clavicular incision provided adequate exposure in 32 (50.0%) of the operating room cases. In the other 50% of operating room cases a combination of a clavicular incision with a median sternotomy or thoracotomy was necessary. Proximal subclavian injuries may be accessed through a clavicular incision combined with a median sternotomy irrespective of left or right site location.

CONCLUSIONS

Subclavian and axillary vascular injuries remain lethal. A clavicular incision provides satisfactory surgical exposure in about half the patients. In patients with proximal injuries addition of a median sternotomy provides adequate surgical access in both right and left subclavian vessels.

Economic climate and cultural diversity: a merging picture

This article explores the merging of a single nonprofit hospital with a nonprofit health care system of hospitals. It also provides the unique financial history of health care reimbursement in California that makes such merges imperative for the success of single hospitals. A unique patient-focused care model, shared governance, and the implications in the financial diversity of merging health care entities also are discussed.

Comparative sequence analysis of human minisatellites showing meiotic repeat instability

The highly variable human minisatellites MS32 (D1S8), MS31A (D7S21), and CEB1 (D2S90) all show recombination-based repeat instability restricted to the germline. Mutation usually results in polar interallelic conversion or occasionally in crossovers, which, at MS32 at least, extend into DNA flanking the repeat array, defining a localized recombination hotspot and suggesting that cis-acting elements in flanking DNA can influence repeat instability. Therefore, comparative sequence analysis was performed to search for common flanking elements associated with these unstable loci. All three minisatellites are located in GC-rich DNA abundant in dispersed and tandem repetitive elements. There were no significant sequence similarities between different loci upstream of the unstable end of the repeat array. Only one of the three loci showed clear evidence for putative coding sequences near the minisatellite. No consistent patterns of thermal stability or DNA secondary structure were shared by DNA flanking these loci. This work extends previous data on the genomic environment of minisatellites. In addition, this work suggests that recombinational activity is not controlled by primary or secondary characteristics of the DNA sequence flanking the repeat array and is not obviously associated with gene promoters as seen in yeast.

Pneumocystis carinii pneumonia in HIV infected patients from South Africa

OBJECTIVE

To compare the spectrum of pulmonary disease in human immunodeficiency virus positive patients of African and European origin, with particular reference to Pneumocystis carinii pneumonia.

DESIGN

Descriptive study with retrospective record review.

SETTING

Tertiary care, university teaching hospitals in Johannesburg, South Africa.

SUBJECTS

Sixty seven HIV-infected patients and 36 HIV-negative renal transplant patients (who served as controls) whose sputa were negative for tuberculosis and Pneumocystis carinii, and who had fibreoptic bronchoscopic evaluation for pulmonary disease between January 1985 and August 1992.

MEASUREMENTS

Histological and cytological evaluation of pulmonary diseases.

RESULTS

In the HIV infected group Pneumocystis carinii pneumonia was the most frequent disease in patients of both African and European origin but occurred less commonly in Africans than in Europeans (27.3% and 58.8%, respectively; p = 0.01). There was no statistically significant difference between patients of African and European origin in the frequency of any other diagnosis. In the renal transplant group the most frequent diagnosis was non-specific interstitial pneumonitis (Africans 33.3%, Europeans 37.0%), followed by Pneumocystis carinii pneumonia (Africans 22.2%, European 14.8%). There was no difference between HIV-infected and renal transplant patients in the frequency of any diagnosis.

CONCLUSION

Pneumocystis carinii pneumonia should be considered in the diagnosis of HIV-infected African patients with pulmonary disease whose sputum smears for tuberculosis are negative.

Inactivation of ataxia telangiectasia mutated gene in B-cell chronic lymphocytic leukaemia

BACKGROUND

Patients with the inherited disorder ataxia telangiectasia (A-T) have an increased susceptibility to lymphoid malignancies. In these patients mutations affect both alleles of the A-T gene (ATM). We have looked for mutations in the ATM gene in sporadic cases of B-cell chronic lymphocytic leukaemia (B-CLL).

METHODS

32 cases of B-CLL were analysed by restriction endonuclease fingerprinting to detect mutations within ATM. In six of the cases in which mutations were detected in tumour samples, germline DNA was screened to assess ATM carrier status. The samples in 20 cases were also studied by western blot for abnormal expression of ATM protein.

FINDINGS

Expression of the ATM protein was impaired in eight (40%) of the 20 tumours analysed, being absent in three and decreased in five. Mutations within ATM were detected in six (18%) of the 32 patients. These point mutations, deletions, and one insertion were distributed across the coding sequence of ATM. Germline mutations, which indicate ATM carrier status, were found in two of these six patients compared with a frequency within the general population of below 1 in 200.

INTERPRETATION

Abnormal expression of ATM protein is a frequent finding in B-CLL. Although the precise function of this protein is unknown, it is thought to have a role in programmed cell death, a deficiency of which would fit with the characteristic phenotype of prolonged cell survival seen in B-CLL tumour cells. Our results also suggest that carriers of ATM mutations may be at a particular risk for the development of B-CLL and this may partly explain the known genetic susceptibility to this disease.

Statistical issues for HIV surrogate endpoints: point/counterpoint. An NIAID workshop

This paper summarizes the proceedings of an NIAID-sponsored workshop on statistical issues for HIV surrogate endpoints. The workshop brought together statisticians and clinicians in an attempt to shed light on some unresolved issues in the use of HIV laboratory markers (such as HIV RNA and CD4+ cell counts) in the design and analysis of clinical studies and in patient management. Utilizing a debate format, the workshop explored a series of specific questions dealing with the relationship between markers and clinical endpoints, and the choice of endpoints and methods of analysis in clinical studies. This paper provides the position statements from the two debaters on each issue. Consensus conclusions, based on the presentations and discussion, are outlined. While not providing final answers, we hope that these discussions have helped clarify a number of issues, and will stimulate further consideration of some of the highlighted problems. These issues will be critical in the proper assessment and use of future therapies for HIV disease.

Prevalence of dental caries: retrospect and prospect

In spite of the general decline in dental caries, as illustrated in national surveys of children's health and by BASCD surveys, considerable unmet need remains. If good oral health is to be ensured for all sections of the UK community, the issues discussed in this article must be addressed.

Detection of cytomegalovirus in upper gastrointestinal biopsies from heart transplant recipients: comparison of light microscopy, immunocytochemistry, in situ hybridisation, and nested PCR

AIM

To establish the diagnostic value of in situ hybridisation and the nested polymerase chain reaction (PCR) in detecting clinically relevant cytomegalovirus (CMV) infection in upper gastrointestinal biopsies from heart transplant patients.

METHODS

Test sensitivity and specificity for detection of CMV early gene RNA by in situ hybridisation and CMV intermediate early gene by PCR were established and then compared with haematoxylin and eosin (H&E) and immunocytochemical detection of CMV in order to establish the best pathological diagnostic approach. All investigations were carried out on formalin fixed, paraffin embedded tissue.

RESULTS

Nested PCR had the highest test sensitivity, followed by in situ hybridisation and immunocytochemistry with the same sensitivity; H&E had the lowest. H&E and immunocytochemistry were the most specific but both had a significant false negative rate which was less of a problem with PCR. However, PCR gave no other diagnostic information, and in situ hybridisation was no better than immunocytochemistry. Both in situ hybridisation and PCR were technically complex and more expensive.

CONCLUSIONS

H&E and immunocytochemistry represent the best initial screen for CMV and other diseases in upper gastrointestinal biopsies from heart transplant patients. If H&E and immunocytochemistry were negative, nested PCR could significantly increase the diagnostic yield of clinically relevant CMV infection. In situ hybridisation appeared to have no advantages and some drawbacks compared with immunocytochemistry and PCR.

Routine helical computed tomographic evaluation of the mediastinum in high-risk blunt trauma patients

BACKGROUND

The indications and method of evaluation of the mediastinum in blunt deceleration trauma are controversial and vary among centers. Most centers practice a policy of angiographic evaluation only in the presence of an abnormal mediastinum on chest radiography. Routine aortography in the absence of any mediastinal abnormality is not widely practiced. Helical computed tomographic (CT) scan has been successfully used in recent studies in the evaluation of the thoracic aorta.

OBJECTIVE

To determine the role of routine helical CT scan evaluation of the mediastinum in patients involved in high-speed deceleration injuries, irrespective of chest radiographic findings.

DESIGN

A prospective study over a 1-year period. Included in the study were patients with high-speed deceleration injuries who required CT evaluation of the head or abdomen. This group of patients underwent routine helical CT evaluation of the mediastinum irrespective of chest radiographic findings.

SETTING

Large, urban, academic level I trauma center.

RESULTS

A total of 112 trauma patients fulfilled the criteria for study inclusion. Overall, there were 9 patients (8.0%) with aortic rupture. Four (44.4%) of these patients had a normal mediastinum on the initial chest x-ray film and the diagnosis was made by CT scan. The CT scan was diagnostic in 8 of the aortic ruptures (intimal tear or pseudoaneurysm) and was suggestive of aortic injury but not diagnostic in 1 patient with brachiocephalic artery injury. In 42 patients (37.5%), there was a widened mediastinum: an aortic rupture was diagnosed in 5 of them (11.9%) and a spinal fracture in 9 (21.4%). One patient had both aortic rupture and spinal injury.

CONCLUSIONS

The incidence of aortic injury in patients with high-speed deceleration injury is high. A significant proportion of patients with aortic injury have a normal mediastinum on the initial chest radiograph. There is a high incidence of spinal injuries in the presence of a widened mediastinum. We recommend that all trauma patients with high-risk deceleration injuries undergo routine helical CT evaluation of the mediastinum irrespective of chest radiographic findings.

Epidemiology of major trauma and trauma deaths in Los Angeles County

BACKGROUND

Our objective was to study population-based trauma-related injuries and deaths in the county of Los Angeles and to identify trends and progress towards meeting the "Year 2000 National Health Objectives."

STUDY DESIGN

We did a retrospective study for the year 1996. Data were obtained from the Trauma Registry of the Emergency Medical Services of the Department of Health Services, and the Coroner's Department of the County of Los Angeles. Traumatic injuries and deaths per 100,000 of the population were calculated according to mechanism, race, age, and gender.

RESULTS

During 1996, there were 12,136 major trauma admissions in the 13 trauma centers in Los Angeles County. Another 1,929 victims died at the scene or were certified dead at nontrauma centers and were taken to the Coroner's Department (total 14,065 victims). The overall major injury rate was 151.0 per 100,000 population and the death rate was 30.9 per 100,000. The trauma death rate per 100,000 population was 56.4 for African-Americans, 33.5 for Hispanics, 26.3 for Caucasians, and 11.6 for Asians. Homicides were the leading cause of traumatic deaths (45.3%) followed by traffic accidents (31.9% of deaths). Firearms were responsible for 3,899 major injuries or deaths (41.7 per 100,000 population). The overall homicide rate per 100,000 population was 14.0, with a much higher rate for African-Americans (40.4 per 100,000) and Hispanics (18.7 per 100,000) than Caucasians (4.0 per 100,000) or Asians (3.4 per 100,000). African-American males were at very high risk for homicide (73.3 per 100,000), and in the age group 15 to 34 years, this problem reaches epidemic proportions (164.2 per 100,000). Traffic accidents accounted for 69.0 major injuries and 9.6 deaths per 100,000 people. Males were at significantly higher risk of dying in traffic accidents than females. People over 60 years of age were at significantly higher risk of traffic-accident death than younger people, for both passenger and pedestrian groups (p < 0.01). Firearm-related suicides were responsible for 4.6 deaths per 100,000 population. Caucasian males over 65 years were at much higher risk of suicide by penetrating trauma (29.5 per 100,000) than were Hispanics (6.3 per 100,000), Asians (5.4 per 100,000), or African-Americans (no deaths) in the same gender and age group.

CONCLUSIONS

Trauma remains a major health problem in the county of Los Angeles. Despite the significant reduction of intentional trauma in 1996, it still exceeds national figures and is much higher than the targeted "Year 2000 National Health Objectives." Aggressive prevention strategies need to focus on the population groups at excessive risks of injury by assault, traffic accidents, and suicides.

Identification of an immunodominant sequential epitope in glycoprotein G of herpes simplex virus type 2 that is useful for serotype-specific diagnosis

A series of 67 oligopeptides that spanned the open reading frame of herpes simplex virus type 2 (HSV-2) glycoprotein G (gG2) were synthesized and tested for reactivity with 173 serum specimens collected from 117 individuals. The oligopeptides were made as multiple antigenic peptides consisting of four copies of a unique sequence attached to a branched lysine core and separated from the core by four glycine residues. The sera included HSV antibody-negative samples as well as sera from individuals from whom HSV had been isolated. Isolated viruses were typed by indirect fluorescence using a panel of type-specific monoclonal antibodies. One peptide, corresponding to residues 561 to 578 of gG2, did not react with any sera lacking HSV-specific antibodies of with sera from HSV-1-infected individuals, but did react with sera from HSV-2-infected individuals. For sera taken seven or more days after initialclinical lesions, the detection rate of the peptide was 92% (47/51), comparable with the 98% (50/51) of truncated glycoprotein D, a sensitive type-common reagent. We conclude that this peptide, of structure (PEEFEGAGDGEPPEDDDSG4)K3A, is an immunodominant type-specific epitope for human antibodies and should be useful for type-specific serodiagnosis of HSV-2. Surprisingly, the epitope lies within one of the most conserved regions of gG1 and gG2. The test can distinguish an initial HSV-2 infection in the presence of a preexisting HSV-1 infection.

Relative bradycardia in patients with traumatic hypotension

BACKGROUND

Tachycardia is considered a physiologic response to traumatic hypotension. The inability of the heart to respond to shock with tachycardia has been described as paradoxical bradycardia or relative bradycardia. The incidence and clinical significance of this condition in major trauma is not known. The objective of this study was to examine the incidence and prognostic significance of tachycardia and relative bradycardia in patients with traumatic hypotension. Relative bradycardia is defined as a systolic pressure < or = 90 mm Hg and a pulse rate < or = 90 beats per minute.

METHODS

This is a retrospective study conducted at a large Level I academic trauma center during a 4-year period. Seventeen demographic and injury severity factors were analyzed for their possible role in tachycardic or bradycardic response in hypotensive patients. Incidence and mortality were derived for each subpopulation. Bivariate analysis of the association of incidence and mortality with each risk factor was performed. Factors with p values < 0.2 were included in stepwise logistic regression analyses that identified significant risk factors and derived adjusted relative mortality risks between tachycardic and bradycardic hypotensive patients.

RESULTS

Excluding transfers and patients dead on arrival, 10,833 major trauma patients were seen during the study period. Seven hundred fifty patients (6.9%) had systolic blood pressure < or = 90 mm Hg; 533 patients had tachycardia (overall incidence of 4.9%, or 71.1% of hypotensive patients), and 217 patients had bradycardia (overall incidence of 2.0%, or 28.9% of hypotensive patients). The overall crude mortality was 29.2% among tachycardia patients and 21.7% among bradycardia patients (crude relative risk = 1.34; 95% confidence interval = 1.00-1.81; p = 0.047). The adjusted relative mortality risk between the two groups was 1.23 (95% confidence interval = 0.84-1.73; p = 0.284). Multivariate analysis showed that patients with relative bradycardia in the subgroups with Injury Severity Scores > or = 16, chest Abbreviated Injury Scale scores > or = 3, or abdominal Abbreviated Injury Scale scores > or = 3 had significantly better survival than patients with similar injuries presenting with tachycardia.

CONCLUSION

Relative bradycardia in hypotensive trauma patients is a common hemodynamic finding. Mortality among tachycardic patients was more predictable than among bradycardic patients using commonly used demographic and injury indicators. The presence of relative bradycardia in some subgroups of patients with severe injuries seems to be associated with better prognosis than the presence of tachycardia.