A trainee's perspective on scientific conferences

Attending and presenting at conferences is a preeminent experience during scientific training. This article provides a trainee's perspective on strategies to promote trainee growth before, during and after scientific meetings, taking the initiatives implemented by the Canadian Society for Immunology (CSI) as an example. A foremost action was the establishment of the Trainee Engagement Committee (TEC) in 2020. The TEC members contribute to the annual symposia by participating in the local organizing committee meetings and organizing trainee-directed events. We propose actions that conference organizers can take to foster the development of the next generation of scientists. In addition, we offer advice to conference presenters on how to craft talks with trainees in mind and to attendees on how to maximize the quality and longevity of conference interactions. We hope this opinion piece evokes reflections and discussions among scientific societies, organizing committees, conference presenters and trainees alike.

Direct in vivo CAR T cell engineering

T cells modified to express intelligently designed chimeric antigen receptors (CARs) are exceptionally powerful therapeutic agents for relapsed and refractory blood cancers and have the potential to revolutionize therapy for many other diseases. To circumvent the complexity and cost associated with broad-scale implementation of ex vivo manufactured adoptive cell therapy products, alternative strategies to generate CAR T cells in vivo by direct infusion of nanoparticle-formulated nucleic acids or engineered viral vectors under development have received a great deal of attention in the past few years. Here, we outline the ex vivo manufacturing process as a motivating framework for direct in vivo strategies and discuss emerging data from preclinical models to highlight the potency of the in vivo approach, the applicability for new disease indications, and the remaining challenges associated with clinical readiness, including delivery specificity, long term efficacy, and safety.

Expansion and Retroviral Transduction of Primary Murine T Cells for CAR T-Cell Therapy

The development of chimeric antigen receptor (CAR) T cells has been a revolutionary technology for the treatment of relapsed and refractory leukemias and lymphomas. The synthetic CAR molecule redirects T cell function toward tumor surface-expressed antigens through a single-chain variable fragment (scFv) fused to CD3z and intracellular costimulatory domains. Here, we describe a protocol for the generation of CAR T cells using primary mouse T cells and a gammaretroviral vector encoding a CAR transgene. This protocol outlines several transduction and expansion methods based on the use of two transduction enhancers, RetroNectin® and Vectofusin®-1, and cell culture systems such as conventional plates or G-Rex® devices.

A highly virulent variant of HIV-1 circulating in the Netherlands

We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log₁₀ increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence.

Discrete-choice experiment to measure patient preferences for the surgical management of colorectal cancer

Background

Establishing trust between a patient and his or her surgeon is of paramount importance. The aim of this study was to assess the relative importance of the ‘attributes of trust’ between surgeon and patient with colorectal cancer.

Methods

A discrete-choice questionnaire was conducted with 60 men and 43 women who had completed primary treatment for colorectal cancer in two teaching hospitals in Sydney, Australia.

Results

Forty-seven of the 103 patients based their choice of surgical management on a single attribute and the remainder were willing to trade between different attributes. In order of importance, patients based their choice of surgical management on specialty training (β coefficient = 0·83), surgeon's communication (β = 0·82), type of hospital (β = 0·72) and who decides treatment (β = 0·01). Patients who were vigilant in their decision-making style and those who did not have tertiary education were more likely to change their preferences in the repeat interview.

Conclusion

Clinicians may have a better chance of meeting a patient's expectations about the process of care if they assess the patient's desire for knowledge and give those who do not have tertiary education more time to assimilate information about their treatment.

Prediction of mortality by exercise echocardiography: a strategy for combination with the duke treadmill score

BACKGROUND

In studies generally involving short follow-up, exercise echocardiography has been shown to predict composite end points. We sought to study the prediction of mortality with this test and to devise a strategy for combination with standard exercise testing.

METHODS AND RESULTS

Clinical, exercise testing, and echocardiographic data were collected in 5375 patients (aged 54+/-14 years, 3880 men) undergoing exercise echocardiography. The Duke treadmill score was derived from the results of treadmill exercise testing. Resting left ventricular (LV) function and the presence and severity of ischemia were interpreted by expert observers. Follow-up at 10.6 years (mean 5.5+/-1.9 years) was complete in 5211 patients (97%). The Duke score classified 59% of patients as low risk, 39% as intermediate risk, and 2% as high risk. Resting LV dysfunction was present in 1445 patients (27%), and the exercise echocardiogram was abnormal in 2525 patients (47%). Death occurred in 649 patients (12%). Over the first 6 years of follow-up, those with normal exercise echocardiograms had a mortality of 1% per year. Ischemia was an independent predictor of mortality. In sequential Cox models, the predictive power of clinical data was strengthened by adding the Duke score, resting LV function, and the results of exercise echocardiography. Exercise echocardiography was able to substratify patients with intermediate-risk Duke scores into groups with a yearly mortality of 2% to 7%.

CONCLUSIONS

A normal exercise echocardiogram confers a low risk of death, and positive results are an independent predictor of death; ischemia is incremental to other data. This test may be particularly useful in patients with intermediate-risk Duke treadmill scores.

Effect of power Doppler and digital subtraction techniques on the comparison of myocardial contrast echocardiography with SPECT

OBJECTIVE

To compare the accuracy and feasibility of harmonic power Doppler and digitally subtracted colour coded grey scale imaging for the assessment of perfusion defect severity by single photon emission computed tomography (SPECT) in an unselected group of patients.

DESIGN

Cohort study.

SETTING

Regional cardiothoracic unit.

PATIENTS

49 patients (mean (SD) age 61 (11) years; 27 women, 22 men) with known or suspected coronary artery disease were studied with simultaneous myocardial contrast echo (MCE) and SPECT after standard dipyridamole stress.

MAIN OUTCOME MEASURES

Regional myocardial perfusion by SPECT, performed with 99mTc tetrafosmin, scored qualitatively and also quantitated as per cent maximum activity.

RESULTS

Normal perfusion was identified by SPECT in 225 of 270 segments (83%). Contrast echo images were interpretable in 92% of patients. The proportion of normal MCE by grey scale, subtracted, and power Doppler techniques were respectively 76%, 74%, and 88% (p < 0.05) at > 80% of maximum counts, compared with 65%, 69%, and 61% at < 60% of maximum counts. For each technique, specificity was lowest in the lateral wall, although power Doppler was the least affected. Grey scale and subtraction techniques were least accurate in the septal wall, but power Doppler showed particular problems in the apex. On a per patient analysis, the sensitivity was 67%, 75%, and 83% for detection of coronary artery disease using grey scale, colour coded, and power Doppler, respectively, with a significant difference between power Doppler and grey scale only (p < 0.05). Specificity was also the highest for power Doppler, at 55%, but not significantly different from subtracted colour coded images.

CONCLUSIONS

Myocardial contrast echo using harmonic power Doppler has greater accuracy than with grey scale imaging and digital subtraction. However, power Doppler appears to be less sensitive for mild perfusion defects.

Effect of power Doppler and digital subtraction techniques on the comparison of myocardial contrast echocardiography with SPECT

OBJECTIVE

To compare the accuracy and feasibility of harmonic power Doppler and digitally subtracted colour coded grey scale imaging for the assessment of perfusion defect severity by single photon emission computed tomography (SPECT) in an unselected group of patients.

DESIGN

Cohort study.

SETTING

Regional cardiothoracic unit.

PATIENTS

49 patients (mean (SD) age 61 (11) years; 27 women, 22 men) with known or suspected coronary artery disease were studied with simultaneous myocardial contrast echo (MCE) and SPECT after standard dipyridamole stress.

MAIN OUTCOME MEASURES

Regional myocardial perfusion by SPECT, performed with (99m)Tc tetrafosmin, scored qualitatively and also quantitated as per cent maximum activity.

RESULTS

Normal perfusion was identified by SPECT in 225 of 270 segments (83%). Contrast echo images were interpretable in 92% of patients. The proportion of normal MCE by grey scale, subtracted, and power Doppler techniques were respectively 76%, 74%, and 88% (p < 0.05) at > 80% of maximum counts, compared with 65%, 69%, and 61% at < 60% of maximum counts. For each technique, specificity was lowest in the lateral wall, although power Doppler was the least affected. Grey scale and subtraction techniques were least accurate in the septal wall, but power Doppler showed particular problems in the apex. On a per patient analysis, the sensitivity was 67%, 75%, and 83% for detection of coronary artery disease using grey scale, colour coded, and power Doppler, respectively, with a significant difference between power Doppler and grey scale only (p < 0.05). Specificity was also the highest for power Doppler, at 55%, but not significantly different from subtracted colour coded images.

CONCLUSIONS

Myocardial contrast echo using harmonic power Doppler has greater accuracy than with grey scale imaging and digital subtraction. However, power Doppler appears to be less sensitive for mild perfusion defects.

Australian Aboriginal trainee health service management program: a new initiative

This paper explores the development, implementation and evaluation of the Australian Aboriginal trainee health service management program in New South Wales. In 1997, the two-year pilot program commenced with ten trainees. The program consisted of a combination of work-based placements, formal university education and Australian College of Health Service Executives (ACHSE) professional development sessions. The program has allowed trainees to gain professional skills and knowledge and broader work experience, in order to increase their employment opportunities throughout the Australian health care system.

Assessment of regional long-axis function during dobutamine echocardiography

Echocardiographic analysis of regional left ventricular function is based upon the assessment of radial motion. Long-axis motion is an important contributor to overall function, but has been difficult to evaluate clinically until the recent development of tissue Doppler techniques. We sought to compare the standard visual assessment of radial motion with quantitative tissue Doppler measurement of peak systolic velocity, timing and strain rate (SRI) in 104 patients with known or suspected coronary artery disease undergoing dobutamine stress echocardiography (DbE). A standard DbE protocol was used with colour tissue Doppler images acquired in digital ciné-loop format. Peak systolic velocity (PSV), time to peak velocity (TPV) and SRI were assessed off-line by an independent operator. Wall motion was assessed by an experienced reader. Mean PSV, TPV and SRI values were compared with wall motion and the presence of coronary artery disease by angiography. A further analysis included assessing the extent of jeopardized myocardium by comparing average values of PSV, TPV and SRI against the previously validated angiographic score. Segments identified as having normal and abnormal radial wall motion showed significant differences in mean PSV (7.9 +/- 3.8 and 5.9 +/- 3.3 cm/s respectively; P < 0.001), TPV (84 +/- 40 and 95 +/- 48 ms respectively; P = 0.005) and SRI (-1.45 +/- 0.5 and -1.1 +/- 0.9 s(-1) respectively; P < 0.001). The presence of a stenosed subtending coronary artery was also associated with significant differences from normally perfused segments for mean PSV (8.1+/-3.4 compared with 5.7+/-3.7 cm/s; P < 0.001), TPV (78 +/- 50 compared with 92 +/- 45 ms; P < 0.001) and SRI (-1.35 +/- 0.5 compared with -1.20 +/- 0.4 s(-1); P = 0.05). PSV, TPV and SRI also varied significantly according to the extent of jeopardized myocardium within a vascular territory. These results suggest that peak systolic velocity, timing of contraction and SRI reflect the underlying physiological characteristics of the regional myocardium during DbE, and may potentially allow objective analysis of wall motion.

Prediction of mortality using dobutamine echocardiography

OBJECTIVES

We sought to find out whether dobutamine echocardiography (DbE) could provide independent prediction of total and cardiac mortality, incremental to clinical and angiographic variables.

BACKGROUND

Existing outcome studies with DbE have examined composite end points, rather than death, over a relatively short follow-up. Clinical and stress data were collected in 3,156 patients (age 63 +/- 12 years, 1,801 men) undergoing DbE. Significant stenoses (>50% diameter) were identified in 70% of 1,073 patients undergoing coronary angiography. Total and cardiac mortality were identified over nine years of follow-up (mean 3.8 +/- 1.9). Cox models were used to analyze the effect of ischemia and other variables, independent of other determinants of mortality.

RESULTS

The dobutamine echocardiogram was abnormal in 1,575 patients (50%). Death occurred in 716 patients (23%), 259 of whom (8%) were thought to have died from cardiac causes. Patients with normal DbE had a total mortality of 8% per year and a cardiac mortality of 1% per year over the first four years of follow-up. Ischemia and the extent of abnormal wall motion were independent predictors of cardiac death, together with age and heart failure. In sequential Cox models, the predictive power of clinical data alone (model chi-square 115) was strengthened by adding the resting left ventricular function (model chi-square 138) and the results of DbE (model chi-square 181). In the subgroup undergoing coronary angiography, the power of the model was increased to a minor degree by the addition of coronary anatomy data.

CONCLUSIONS

Dobutamine echocardiography is an independent predictor of death, incremental to other data. While a normal dobutamine echocardiogram predicts low risk of cardiac death (on the order of 1% per year), this risk increases with the extent of abnormal wall motion at rest and stress.

Application of tissue Doppler to interpretation of dobutamine echocardiography and comparison with quantitative coronary angiography

The main limitation of dobutamine echocardiography (DE) is its subjective interpretation. We sought to reduce the need for expert interpretation by developing a quantitative approach to DE using myocardial Doppler velocity (MDV) in 242 patients undergoing DE. In 128 patients with a normal dobutamine echocardiogram, the normal range was designed to give a specificity of 80%. The accuracy of this range was investigated in 114 consecutive patients who underwent coronary angiography within 2 months of DE. A standard dobutamine echocardiographic protocol was used, with MDV gathered from color tissue Doppler at rest and peak stress. Wall motion at these stages was scored by experienced observers using a 16-segment model and MDV was measured off-line. Sensitivity and specificity of wall motion scoring and MDV were obtained by comparison with angiographic evidence of disease, defined as stenosis > 50% of the coronary artery diameter. The normal range in tethered segments (septum, anteroseptum, and inferior) was > or = 7 cm/s in the basal segments and > or = 5 cm/s in the midsegments. In the free wall (anterior, lateral, and posterior), the cutoff was > or = 6 cm/s in the base and > or = 4 cm/s in the midventricle. Of 114 patients undergoing angiography, 84 (75%) had significant stenoses, and the sensitivity of wall motion scoring and MDV were 88% and 83%, respectively, with specificities of 81% and 72% (p = NS). The accuracy was similar overall (86% vs 80%), as well as in each vascular territory. These data suggest that a fully quantitative interpretation of DE using site-specific normal ranges of tissue Doppler, which account for regional variations of base-apex function, is feasible and equivalent in accuracy to expert wall motion scoring.

A. V. Hernandez, 'Duplicate coverage and demand for health care. The case of Catalonia'. Health economics 8(7) 1999, 579-598

The original article to which this Erratum refers was published in Health Economics 8(7) 1999, 579-598.

The veil of experience: do consumers prefer what they know best?

There is growing interest from health policy makers in eliciting consumer preferences for health care services. This is particularly the case when assessing the likely impact of innovations. Some people may be wary of innovations because they prefer the service they have previously experienced. Consumer preferences for an existing and a hypothetical new bowel cancer testing programme were measured using a discrete choice experiment questionnaire. The results showed that consumers had a statistically significant preference for the existing service (status quo) when all other factors remained constant. It suggested that consumers make decisions under a 'veil of experience'. Possible explanations for this result include the endowment effect, status quo bias and loss aversion. Future evaluations of health service innovation should be aware of this tendency to favour the status quo.

An Approach to Defining and Operationalizing Critical Thinking

The faculty in a midwestern university confronted the imperative to define and measure critical thinking in the nursing undergraduate curriculum. Theoretical and operational definitions were developed by faculty through literature review, extensive discussion, student participation, and evaluation. These activities also led to the generation of a list of indicators to assess the presence of critical thinking. Through the process faculty have developed a deeper understanding of critical thinking and fostered students' critical thinking abilities.

Bridging prevention and practice: public health and family violence

Public health approaches the primary prevention of family violence by focusing on surveillance, the identification of risk factors, and the development, evaluation, and dissemination of interventions. Physicians and other health care providers are crucial in this process because they are in a unique position to identify at-risk individuals and populations and to implement both broad-based and targeted preventive and intervention initiatives. Incorporating public health principles into medical education and medical practice not only can reduce the severity of this epidemic by strengthening efforts in early detection and expert intervention but also can create effective primary prevention, an important necessary step towards eradicating every disease or condition. This article discusses the role of public health professionals in preventing family and intimate violence. It notes specific findings from public health research, including the cycle of violence and the need to incorporate issues of abuse across the life span, and other factors, into medical education. Addressing family and intimate violence in a caring and sensitive manner is difficult, and incorporating public health principles into medical education and medical practice can forge an effective partnership between medical practitioners and public health professionals. This new partnership represents both an important challenge and a unique opportunity to understand family and intimate violence and thus to develop and evaluate effective short- and long-term solutions.

Estriol: a potent regulator of TNF and IL-6 expression in a murine model of endotoxemia

The increased incidence of autoimmune disease in premenopausal women suggests the involvement of sex steroids in the pathogenesis of these disease processes. The effects of estrogen on autoimmunity and inflammation may involve changes in the secretion of inflammatory mediators by mononuclear phagocytes. Estradiol, for example, has been reported to regulate TNF, IL-6, IL-1 and JE expression. In the present study the effects of the estrogen agonist, estriol, on cytokine expression have been investigated in mice administered a sublethal lipopolysaccharide, LPS, challenge. Pretreatment of mice with pharmacologic doses of estriol, 0.4-2 mg/kg, resulted in a significant increase in serum TNF levels in both control and autoimmune MRL/lpr mice, following LPS challenge. This increase in TNF over the placebo group was blocked by the estrogen antagonist tamoxifen. Estriol treated mice also exhibited a rapid elevation in serum IL-6 levels following LPS challenge with the peak increase occurring 1 hr post LPS. This contrasted with the placebo group in which maximal serum IL-6 levels were detected at 3 hrs post challenge. This shift in the kinetics of IL-6 increase by estriol was inhibited by tamoxifen. The estriol mediated effects of TNF and IL-6 serum levels were consistent with the changes in TNF and IL-6 mRNA observed ex vivo in elicited peritoneal macrophages. Macrophage cultures from estriol treated animals however, did not demonstrate significant differences from the placebo group for TNF or NO secretion following in vitro LPS challenge. These results suggest that the estrogen agonist estriol can have significant quantitative, TNF, and kinetic, IL-6, effects on inflammatory monokines produced in response to an endotoxin challenge.

The effect of a selective estrogen receptor modulator on the progression of spontaneous autoimmune disease in MRL lpr/lpr mice

The MRL lpr/lpr mouse strain is an animal model for the autoimmune disorder systemic lupus erythematosus (SLE). Pathologic changes in the mice include a severe proliferative glomerulonephritis, lymph node and spleen enlargement, increase in autoantibody titers, and shortened life spans. In the present investigation, female MRL lpr/lpr mice have been dosed po daily for 7 months with the selective estrogen receptor modulator (SERM) LY139478 (4 mg/kg) or 17alpha-ethinylestradiol (EE2, 1 mg/kg) and compared to vehicle control animals. The LY139478 group had an increase in survival (73% survival at 7 months, P = 0.02) but the EE2-treated animals did not (53% survival at 7 months, P = 0.4) when compared to the control group (32% survival at 7 months). Although there were no reductions in autoantibody levels as determined by anti-DNA antibody ELISA, histological analysis of kidney tissue indicated that both LY139478 and EE2 mitigated the progression of glomerular nephritis which was evident in the controls. In contrast, there were no significant differences in lymph node size although the LY139478 and EE2 groups retained a well-defined sinusoidal region. Finally, flow cytometric analysis documented that thymuses from animals treated for 7 months with LY139478 but not with EE2 contained predominantly CD4+/CD+ T cells consistent with a normal thymic phenotype observed in non-MRL lpr/lpr mouse strains. These studies demonstrate that SERMs may be potentially useful for the treatment of autoimmune disorders.

In vivo modulation of murine serum tumour necrosis factor and interleukin-6 levels during endotoxemia by oestrogen agonists and antagonists

Oestrogen has been reported to modulate tumour necrosis factor (TNF), interleukin (IL)-1 and IL-6 cytokine levels in human mononuclear cell cultures. In the present study, the effects of exogenous oestrogen administration on the cytokine response to an endotoxin challenge was investigated in a murine model of endotoxemia. Animals pretreated for 4 days with 17 alpha ethinyl oestradiol exhibited divergent regulation of TNF and IL-6 levels in sera from endotoxin-stimulated mice. Oestrogen treatment resulted in a significant increase in serum TNF while serum IL-6 levels, relative to the placebo group, decreased in response to an endotoxin challenge. These oestrogenic effects were dose dependent with maximal elevations observed in TNF at 1 mg/kg and maximal reduction in IL-6 at 0.1 mg/kg of 17 alpha ethinyl oestradiol. The increase in TNF levels by ethinyl oestradiol was blocked by co-administration of the oestrogen receptor antagonist tamoxifen. Oestrogen-mediated modulation of the TNF and IL-6 response to endotoxin was also apparent in animals implanted with 17 beta oestradiol pellets. The oestrogen-mediated effects on serum IL-6 were consistent with a reduction in IL-6 mRNA in peritoneal macrophages from oestrogen-treated mice. The effects of oestrogen on TNF and IL-6 production were also investigated in vitro. Oestradiol-treated macrophage cultures produced three- to fourfold lower amounts of IL-6 without any significant modulatory effects on TNF secretion. The combined in vivo and in vitro results demonstrate the modulation of IL-6 and TNF during endotoxemia by oestrogen analogues through an oestrogen receptor-dependent mechanism.

Patient and nurse criteria for heart transplant candidacy

The criteria nurses and patients believe should be used to allocate hearts for transplantation were explored and compared in a descriptive study. Although the majority of both groups agreed that patients with AIDS or who are HIV positive should not receive a transplant, the two groups agreed very little on the other criteria. This research has implications for clinical care and ethical decision making.

School-based programs to reduce sexual risk behaviors: a review of effectiveness

This review was undertaken in recognition of the mounting public health and social problems associated with adolescent sexual behavior and the importance of basing school-affiliated programs designed to reduce sexual risk-taking behavior on sound research. The authors were commissioned by the Division of Adolescent and School Health within the Centers for Disease Control and Prevention, Public Health Service, to review carefully the research on these programs and to assess their impact on behavior. The authors identified 23 studies of school-based programs that were published in professional journals and measured program impact on behavior. They then summarized the results of those studies, identifying the distinguishing characteristics of effective programs, and citing important research questions to be addressed in the future. Not all sex and AIDS education programs had significant effects on adolescent sexual risk-taking behavior, but specific programs did delay the initiation of intercourse, reduce the frequency of intercourse, reduce the number of sexual partners, or increase the use of condoms or other contraceptives. These effective programs have the potential to reduce exposure to unintended pregnancy and sexually transmitted disease, including HIV infection. These programs should be replicated widely in U.S. schools. Additional research is needed to improve the effectiveness of programs and to clarify the most important characteristics of effective programs.

The NCLEX-RN and Nurse Educators

The involvement of nurse educators with recent NCLEX-RN changes was studied. One hundred and twenty administrators from associate (ADN) and baccalaureate (BSN) degree programs across the country responded to a questionnaire regarding educator knowledge about, involvement in, and opinion of the change process. Findings revealed that administrators from both program types felt ill-informed regarding NCLEX-RN changes prior to their implementation, and they expressed a desire to have had input in the change process. While administrators had varied opinions regarding the passing standard change and the content change, they were strongly opposed to the manner in which change occurred.

Pressure pain threshold evaluation of the effect of spinal manipulation in the treatment of chronic neck pain: a pilot study

Nine subjects with chronic mechanical neck pain syndromes were evaluated for pressure pain threshold (PPT) over standardized tender points in the paraspinal area surrounding a manipulable spinal lesion. The subjects were then allocated randomly to an intervention consisting of either an oscillatory mobilization of the cervical spine (n = 4), which was designated as the control procedure, or a rotational manipulation of the cervical spine (n = 5). An assessor-blinded re-evaluation of the pressure pain threshold levels was conducted after 5 min. In the group receiving a manipulation the mean increases in pressure pain threshold ranged from 40-56% with an average of 45%. In the control group no change in any of the pressure pain thresholds was found. These results were analyzed using ANOVA and were found to be statistically significant (p less than 0.0001). This study confirms that manipulation can increase local paraspinal pain threshold levels. The use of the pressure pain threshold meter allows for the determination of such a beneficial effect in the deeper tissues.

Relevance of protein binding to cephalosporin antimicrobial activity in vivo

Protein binding, serum kinetics and minimum inhibitory concentrations (MICs) for Staphylococcus aureus were determined for cefoxitin, cefazolin, ceftazidime and ceftriaxone in the rabbit. MICs of cefazolin and cefoxitin were also measured for Escherichia coli. Varying concentrations of the bacteria were administered intradermally to create areas of cellulitis, which were quantified as mean erythematous areas (EAs). Despite large differences in protein binding of the antibiotics (range 12-88%) and antibiotic dosing to allow serum concentrations to drop below the respective MICs, there was no statistical difference in the mean EAs of the animals after bacterial challenge. Antibiotic protein binding did not alter the course of cellulitis nor correlate with bacterial MIC in this model.

A comparison of pulse oximeters during helicopter flight

Pulse oximetry would be an invaluable parameter to monitor during patient transport. While original models of oximeters were not battery powered nor very portable, this has changed. Seven currently available commercial pulse oximeter models were evaluated in the noisy vibration-prone environment of a helicopter. Three (3) units were judged to be unacceptable on the basis of weight, duration of battery life, or lack of ease of use. In two (2) units, the sampling algorithms appeared to interface with their performance. Of the seven (7) units tested, two (2) units were found to be reliable, portable, and easy to use. The use of portable pulse oximetry monitors should rapidly become routine during the transport of critically ill patients.

Serum level monitoring of aminoglycoside antibiotics. Limitations in intensive care unit-related bacterial pneumonia

Serum aminoglycoside assays have been accepted as useful methods of enhancing therapeutic efficacy in the treatment of intensive care unit-acquired pneumonia and in avoiding aminoglycoside nephrotoxicity. We prospectively studied 68 surgical patients with normal renal function and gram-negative bacterial pneumonia who were treated with aminoglycosides. Serum levels indicated subtherapeutic levels in 47 patients and verified optimum levels in 13 patients. Toxic trough levels developed in six patients and, despite immediate dosage adjustment, five patients suffered nephrotoxicity. Six additional patients also had nephrotoxicity. Five of these patients never had toxic peak or trough levels and rising trough levels developed in one patient after serum creatinine levels began to rise. We conclude that routine monitoring of serum levels effectively detects subtherapeutic antibiotic levels. This modality is useful for optimizing dosage schedules, but does not serve to predict or avoid nephrotoxicity in critically ill surgical patients.