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Biomedical subjects

L J Baraff

Publications and source records attributed to L J Baraff.

At least 91 records · Page 5Linked to original sources
PubMed1984

Research topics, author's specialty, and funding sources of articles published in an emergency medicine journal.

All original articles published in JACEP and Annals of Emergency Medicine in 1972, 1975, 1978, and 1981 were reviewed and classified according to topic, author's specialty, and funding source. The number of articles published in each category was as follows: toxicology, 44; emergency medical services (EMS), 34; general surgery, 31; emergency department, 28; educational techniques, 19; orthopedics, 17; cardiovascular disease, 15; pulmonary, 13; cardiopulmonary resuscitation (CPR), 10; shock, 8; airway management, 8; and other, 71. The number of authors per article ranged from one to eight; the mean number of authors increased from 1.1 in 1972 to 2.6 in 1981 (P less than .001). The authors' backgrounds most frequently included were as follows: emergency medicine, 53.4%; surgery, 12.8%; internal medicine, 7.9%; and pediatrics, 1.6%. The percentage of articles with specific funding sources increased from 2.9% in 1972 to 25% in 1978, then decreased to 14.3% in 1981. The percentage for each funding source was as follows: government, 7.9%; industry, 2.0%; university, 3.3%; foundation, 2.0%; other, 1.0%; and none, 83.8%. This study demonstrates that there is a defined body of knowledge in emergency medicine, that emergency physicians author the majority of publications in this emergency medicine journal, and that emergency medicine is not supported by traditional funding sources.

Authorship↗
PubMed1984

Immunologic response to early and routine DTP immunization in infants.

The effect of early immunization, prior to discharge from the newborn nursery, on subsequent immunity as determined by enzyme-linked immunosorbent assay (ELISA) immunoglobulin (Ig) M and IgG antibody titers to filamentous hemagglutinin and lymphocytosis-promoting toxin (LPT) of Bordetella pertussis and by standard pertussis agglutinin titers was investigated. Eighteen infants received routine diphtheria-tetanus-pertussis (DTP) immunization at 2, 4, and 6 months of age; 17 other infants received routine immunization and an additional DTP immunization in the newborn nursery. Antibody was determined on samples of cord blood and whole blood obtained at 4, 6, and 9 months of age. IgM anti-filamentus hemagglutinin was significantly higher at 4 and 6 months of age in the group that received early immunization (P less than .05). There was no significant difference in IgM anti-LPT, IgG anti-filamentus hemagglutinin, IgG anti-LPT, or pertussis agglutinin antibodies. Six control infants had high cord IgG anti-LPT titers. These six infants had significantly lower antibody titers to LPT at 6 and 9 months of age when compared with control with control infants with lower cord titers. Thirteen infants in the early immunization group with lower cord IgG anti-LPT titers achieved significantly lower titers at 9 months of age than the 12 comparable infants in the control group.

Bacterial Toxins↗
PubMed1984

DTP-associated reactions: an analysis by injection site, manufacturer, prior reactions, and dose.

Local and less serious systemic reactions are frequent following immunization with diphtheria-tetanus-pertussis (DTP) vaccine. The effects of injection site, manufacturer, previous reactions, and dosage reduction upon subsequent reactions to DTP immunization were investigated. Local reactions, notably pain and swelling, were less common when the immunization was given in the buttocks than in the thigh. No injection site was consistently associated with lower systemic reaction rates. There was no significant difference in the rate of more serious reactions by vaccine manufacturer. Differences in rates of less serious reactions by manufacturer were observed but seemed to be related to vaccine lot differences rather than the specific vaccines. In a subset of 772 children, in whom data regarding sequential reactions were available, it was noted that all three reactions investigated--local redness, temperature greater than or equal to 39 degrees C, and persistent crying longer than one-half hour--were two to three times more frequent on a subsequent immunization when present on a prior vaccination than if not present on a prior vaccination than if not present previously. One hundred children received a half dose of DTP vaccine because of a less serious reaction associated with prior immunization. In all instances, they had significantly less serious local reactions as well as notable differences in temperature, drowsiness, and persistent crying.

Child↗
PubMed1983

A review of research methodology in an emergency medicine journal.

All original articles published in JACEP and Annals of Emergency Medicine in 1972, 1975, 1978, and 1981 were reviewed and classified according to type of article, research design, specific methods utilized, and statistical analyses employed. The number of articles published annually increased during the 10-year period, from 34 in 1972 to 131 in 1981. The percentage of articles devoted to clinical research, basic science, animal studies, and health services research also increased: 1972, 8.8%; 1975, 39.6%; 1978, 41.2%; and 1981, 51.1%. In 1972, only two studies had defined research designs. In 1981, 47 studies had the following research designs: case control, 9; cohort, 9; cross-sectional, 13; uncontrolled clinical trial, 3; non-random clinical trial, 7; and randomized clinical trial, 6. Research methodologies were defined in only two studies published in 1972, but increased in each of the years reviewed to 41 in 1978. The most common methodology was the use of diagnostic categories. In 1972, statistical analysis was limited to descriptive enumeration and was included in only three articles. In 1981, 62 articles contained statistical analyses, including chi square in 11; t test in 6; Fischer's exact test in 2; ANOVA in 4; and P value (method not stated) in 10. This study reveals a major increase in both the quality and quantity of emergency medicine research published during the 10-year period reviewed.

Emergency Medicine↗
PubMed1983

Efficacy of cervical spine immobilization methods.

Cervical spine immobilization devices are widely used to stabilize the cervical spine and prevent neurologic deficits associated with unstable fractures. In order to quantitate their efficacy we measured controlled cervical spine motion in three axes, using six different immobilization methods in 25 volunteers instructed to actively move their necks as much as possible in the directions of flexion, extension, rotation, and lateral bending while lying supine. Control measurements were made with no device and measurements were repeated following immobilization with: soft collar (SC), hard collar (HC), extrication collar (EC), Philadelphia collar (PC), bilateral sandbags joined with 3-inch cloth tape across the forehead (ST), and the combination of sandbags, tape, and the Philadelphia collar (ST/PC). Neck movements were reported in degrees recorded on a hand-held goniometer. There were no significant differences between control and SC measurements except in rotary movement. PC was not significantly better than the other two types of hard collars, except in limiting extension. ST immobilization was significantly better than any of the other four methods used alone, for all four movements. The addition of PC to ST was significantly more effective in reducing extension only.

Adolescent↗
PubMed1983

Serological response to filamentous hemagglutinin and lymphocytosis-promoting toxin of Bordetella pertussis.

Serum antibody responses to the filamentous hemagglutinin and the lymphocytosis-promoting toxin of Bordetella pertussis after vaccination with diphtheria and tetanus toxoids and pertussis vaccine, adsorbed, were assayed by using the enzyme-linked immunosorbent assay. The effect of early immunization, during the first week of life, on the antibody response also was determined. After vaccination, immunoglobulin G (IgG) and IgM directed against both the filamentous hemagglutinin and the lymphocytosis-promoting toxin were detected. Generally, antibody titers increased with subsequent injections and the age of the children. Maternal antibodies against filamentous hemagglutinin and lymphocytosis-promoting toxin were detected in cord blood. The ability of an infant to produce serum IgG anti-lymphocytosis-promoting toxin after vaccination with pertussis vaccine was inversely related to the cord blood serum IgG anti-lymphocytosis-promoting toxin titer at birth. A good antibody response was observed in infants with low cord blood titers, and a poor antibody response was seen in infants with high cord blood values. The IgM anti-lymphocytosis-promoting toxin response was good in groups with both low and high cord blood titer, with no significant difference observed between the two groups. No IgA anti-lymphocytosis-promoting toxin or IgA anti-filamentous hemagglutinin titers were observed in vaccines. IgA antibodies were observed in convalescent sera from two adults and may be presumptive evidence of infection with B. pertussis.

Antibodies, Bacterial↗
PubMed1982

Transcutaneous oxymetry measurements during acute blood loss.

Transcutaneous PO2 (TcPO2) was measured in healthy adult blood donors to test the sensitivity of this method as a noninvasive means of diagnosing occult blood loss. TcPO2, the energy required to heat the electrode (MW), and postural changes in blood pressure and pulse, were measured before and after a 450-ml blood donation. There was a significant increase (P less than .005) in postural pulse of 4.8/min, but no significant change (P greater than .05) in postural blood pressure. There was no significant change (P greater than .05) in TcPO2, but there was a significant decrease (P less than .001) in MW. These MW changes probably reflect physiologic changes associated with blood loss.

Blood Pressure↗
PubMed1982

Effect of pneumatic trousers on pulmonary function.

Little information is available concerning the effect of pneumatic antishock trousers (PT) on pulmonary function. To examine this issue, we measured the effects of PT inflation on forced expired volumes, subdivisions of lung volumes, quasistatic lung compliance, single-breath diffusing capacity for carbon monoxide, and transdiaphragmatic pressure at resting lung volume in 10 healthy nonsmoking adults. All subjects were studied seated without PT, supine with PT uninflated, and supine with PT inflated to 100 mm Hg. When seated subjects assumed the supine position without PT inflation, significant reductions were found in the forced expired volume in 1 sec, in subdivisions of lung volume, total lung capacity (TLC), functional residual capacity (FRC), expiratory reserve volume (ERV) and in transdiaphragmatic pressure. However, PT inflation itself did not produce significant changes in any of the measured pulmonary indices except transdiaphragmatic pressure. We conclude that PT inflation in supine normovolemic individuals does not produce acutely significant alterations in lung function.

Adult↗
PubMed1981

Nature and rates of adverse reactions associated with DTP and DT immunizations in infants and children.

In 784 DT and 15,752 DTP immunizations given to children 0 to 6 years of age who were prospectively studied for reactions occurring within 48 hours following immunization, minor reactions were significantly more frequent following DTP vaccine. The ratio of reaction rates associated with DTP and DT immunizations (DTP/DT) for selected local and systemic reactions was as follows: local redness, 37.4%/7.6%; local swelling, 40.7%/7.6%; pain, 50.9%/9.9%; fever, 31.5%/14.9%; drowsiness, 31.5%/14.9%; fretfulness, 53.4%/22.6%; vomiting, 6.2%/2.6%; anorexia, 20.9%/7.0% and persistent crying, 3.1%/0.7%. Following DTP immunization nine children developed convulsions and nine developed hypotonic hyporesponsive episodes. No sequelae were detected following these reactions.

Child↗
PubMed1979

Haemophilus influenzae meningitis. A national study of secondary spread in household contacts.

To determine the risk of severe Haemophilus influenzae illness among household contacts of patients with H. influenzae meningitis, we studied prospective data obtained in 19 states from January 1, 1977, to June 30, 1978. H. influenzae meningitis was reported in 1403 patients, and 1147 (82 per cent) of the exposed families were investigated for the occurrence of H. influenzae disease within 30 days after its onset in the index patient. During this interval, nine of 1687 household contacts (0.5 per cent) under the age of six years had systemic disease confirmed to be caused by H. influenzae Type b. The risk in children less than one year of age was 6 per cent, and the risk in those less than four years of age was 2.1 per cent. None of 2624 contacts above the age of five was affected. In the 30 days after onset of meningitis, the risk of this infection alone, aside from other types of serious H. influenzae disease, is 585 times greater in household contacts than the age-adjusted risk in the general population. The risk of H. influenzae disease in household contacts under six years of age is similar to the risk of secondary meningococcal disease in all household contacts--indicating a need for effective antimicrobial prophylaxis.

Adolescent↗
PubMed1979

Poststreptococcal acute glomerulonephritis: fact and controversy.

Poststreptococcal acute glomerulonephritis is prototypic of the immunologic glomerulonephritides. It most commonly follows streptococcal infection of the pharynx or skin. The diagnosis is usually not difficult when a nephritic clinical presentation (with such manifestations as hematuria, edema, and hypertension) is associated with serologic evidence of recent streptococcal infection and a depressed serum complement concentration. Currently, however, the nephritogenic antigen(s) has not been identified and has not been shown to be the same antigen for all nephritogenic streptococci; it may not even be a part of the infecting organism. The development of a vaccine to prevent this illness from occurring is therefore still not possible. Whether poststreptococcal acute glomerulonephritis progresses to chronic renal failure is still uncertain. Painstaking laboratory research together with careful, prospective long-term follow-up studies of patients with poststreptococcal acute glomerulonephritis may provide some of the answers to these critical questions.

Acute Disease↗
PubMed1978

Differential inactivation of cephapirin vs. cephalothin by penicillin-resistant strains of Staphylococcus aureus: a preliminary study.

The bactericidal effectiveness of cephapirin and cephalothin against small (approximately 10(5)) and large (approximately 10(8)) inocula of penicillin-resistant Staphylococcus aureus was evaluated. With the smaller inoculum, no differences in bactericidal activity between the two drugs (tested at 2 and 40 microgram/ml) were seen after incubation for 2, 4, 6, or 24 hr. Neither cephalosporin effectively killed a larger inoculum in a concentration of 250 times the minimal bactericidal concentration for selected strains. Total inactivation of cephapirin (40 microgram/ml) by eight of 13 strains was demonstrated with the larger inoculum. These preliminary studies indicate that inactivation of cephapirin is pH-dependent. No strain inactivated cephapirin in less than or equal to 4 hr. Inactivation was independent of temperature at 37 C and 42 C. Although cephalothin was resistant to inactivation under the same conditions, the inoculum required to inactivate cephapirin was not killed by 100 microgram of cephalothin/ml. Although strains of S. aureus that slowly inactivate cephapirin appear to be prevalent, no strain that rapidly inactivates this cephalosporin was identified.

Cephalosporins↗
PubMed1978

Failure of cefamandole in treatment of meningitis due to Haemophilus influenzae type b.

The in vitro activity of cefamandole was determined against 58 isolates of Haemophilus influenzae type b; 47 were beta-lactamase-negative (ampicillin-susceptible), and 11 produced beta-lactamase (ampicillin-resistant). Ampicillin-susceptible strains were susceptible to cefamandole with a median minimal bactericidal concentration (MBC) of 0.4 microgram/ml. Ampicillin-resistant strains had a median MBC of 0.8 microgram/ml. Prior studies have documented these concentrations of cefamandole in cerebrospinal fluid in the presence of inflamed meninges. Three children with meningitis due to H. influenzae type b were treated with cefamandole (200 mg/kg per day), including one child with disease due to an ampicillin-resistant strain. All patients showed clinical improvement during therapy. However, sterility of the cerebrospinal fluid was never achieved in two patients during 72--96 hr of therapy with cefamandole. The third patient relapsed with a recurrence of positive cultures during the seventh day of cefamandole therapy. Therefore, cefamandole does not appear to be a useful agent for treatment of meningitis due to H. influenzae type b irrespective of in vitro susceptibility or evidence of penetration into the cerebrospinal fluid.

Ampicillin↗
PubMed1978

The role of antibiotics, immunizations, and adenoviruses in pertussis.

Sixty-five patients with pertussis were identified by a clinical criterion, and Bordetella pertussis was isolated from 75% of these patients or their symptomatic household contacts. Negative nasopharyngeal cultures were usually associated with either a history of antibiotic therapy with erythromycin or tetracycline (two of three patients), two or more diphtheria and tetanus toxoids with pertussis (DTP) vaccines (six of eight patients), or both (two of three patients). Erythromycin therapy resulted in the elimination of B. pertussis from the nasopharynx in 2 to 7 days (mean, 3.6 days) compared with 7 to 17 or more days (mean, greater than 12 days) in patients treated with no antibiotics, but had no effect on the duration or severity of illness as judged by length of hospitalization. Adenoviruses were recovered from five of 44 patients cultured. Four of these isolates were from throat swabs obtained early in the illness and the remaining isolate was from one of 33 repeated viral cultures obtained two to three weeks later; B. pertussis was also isolated from these five patients. Paired serum samples were obtained from only two of these patients. Neither demonstrated a fourfold rise in adenoviral complement-fixing antibodies. Therefore, in these patients, adenoviral isolation may have been secondary to reactivation of a latent viral infection by infection with B. pertussis.

Adenoviridae↗