Electroencephalography during out-of-hospital cardiopulmonary resuscitation.

BACKGROUND: At the present time there is no parameter that can estimate the quality of cerebral perfusion and possible success of cerebral resuscitation during advanced cardiac life support (ACLS) efforts. In recent years, various attempts have been made to use electroencephalography (EEG)-based cerebral neuromonitoring to assess the effectiveness of cardiopulmonary resuscitation (CPR). OBJECTIVES: The Cerebral State Monitor M3 (Danmeter A/S, Odense, Denmark) is a portable, single-channel EEG monitor that provides the user with different EEG-based parameters and the raw waveform EEG to measure cerebral activity. CASE REPORT: We report two cases of out-of-hospital CPR with single-channel EEG monitoring conducted parallel to ACLS with external chest compressions. We demonstrate an artifact in waveform EEG recordings that is caused by the external chest compressions, and that leads to a miscalculation of the Burst Suppression Ratio and Cerebral State Index. CONCLUSION: These cases suggest that digitally processed EEG-monitoring is not a useful tool during CPR.

Single-channel electroencephalography of epileptic seizures in the out-of-hospital setting: an observational study.

OBJECTIVES: To evaluate whether single-channel electroencephalography (EEG) recording can be conducted in the out-of-hospital setting and whether it can be used to record electrographic signs of convulsive epileptic seizures. METHODS: This prospective observational feasibility study included patients who presented with a recent or ongoing epileptic seizure during out-of-hospital emergency treatment. Bifrontal single-channel EEG recordings were conducted by ambulance physicians throughout the initial treatment. The data recorded were analysed for the quality of recording and the occurrence of ictal EEG patterns. RESULTS: There were 45 adult patients who had a recent or an ongoing epileptic seizure in the study group and 15 patients with no neurological disorders in the control group. The median percentage of time during which no artefacts were detected by the device was 88.0% in the study group and 96.0% in the control group. EEG recordings for 3 out of 45 (6.6%) patients were of poor quality and not evaluable. Spike/wave or polyspike patterns were found in 98% and 100% of patients in the study and control groups, respectively, whereas the occurrence of periodic epileptiform discharges and delta waves with spikes showed a sensitivity and specificity of 100% (10/10) for the presence of an ongoing epileptic seizure. CONCLUSIONS: Single-channel EEG can be performed outside the hospital and yields useful recordings in most patients with acceptable rates of artefact. The diagnosis of generalised convulsive epileptic seizures by offline analysis of out-of-hospital EEG showed a high sensitivity and specificity when compared with the clinical diagnosis.

Comparison of the over-the-head, lateral and alternating positions during cardiopulmonary resuscitation performed by a single rescuer with a bag--valve--mask device.

BACKGROUND: The 2005 guidelines for cardiopulmonary resuscitation (CPR) do not include a statement on performance of basic life support by a single healthcare professional using a bag-valve-mask device. Three positions are possible: chest compressions and ventilations from over the head of the casualty (over-the-head CPR), from the side of the casualty (lateral CPR), and chest compressions from the side and ventilations from over the head of the casualty (alternating CPR). The aim of this study was to compare CPR quality of these three positions. METHODS: 102 healthcare professionals were randomised to a crossover design and performed a 2-min CPR test on a manikin for each position. RESULTS: The hands-off time over a 2-min interval was not significantly different between over-the-head (median 31 s) and lateral (31 s) CPR, but these compared favourably with alternating CPR (36 s). Over-the-head CPR resulted in significantly more chest compressions (155) compared with lateral (152) and alternating CPR (149); the number of correct chest compressions did not differ significantly (119 vs 122 vs 109). Alternating CPR resulted in significantly less inflations (eight) compared with over-the-head (ten) and lateral CPR (ten). Lateral CPR led to significantly less correct inflations (three) compared with over-the-head (five) and alternating CPR (four). CONCLUSIONS: In the case of a single healthcare professional using a bag-valve-mask device, the quality of over-the-head CPR is at least equivalent to lateral, and superior to alternating CPR. Because of the potential difficulties in bag-valve-mask ventilation in the lateral position, the authors recommend over-the-head CPR.

Single-channel amplitude integrated EEG recording for the identification of epileptic seizures by nonexpert physicians in the adult acute care setting.

OBJECTIVE: Although several studies have shown the potential of amplitude integrated electroencephalography (aEEG) in detecting neonatal seizures, no publications have evaluated the diagnostic use of aEEG for the detection of seizures in adult patients. METHODS: In this prospective blinded observational study, bifrontal single-channel electroencephalography (EEG) recordings were performed with a portable EEG monitor (CSM M3 ICU, Danmeter-Goalwick Holdings Limited, Odense, Denmark) during the out-of-hospital care of emergency cases. Four intensive care unit (ICU) physicians received training in the interpretation of aEEG recordings. After the training they evaluated the stored aEEG traces for the presence of epileptic seizure activity during the recording time. The physicians were blinded to the clinical data of the patients. The results obtained were compared with the clinical diagnosis and the evaluation of the raw EEG signal. The level of interrater agreement was quantified using Fleiss' ĸ. RESULTS: The aEEG traces from 10 patients with generalized epileptic seizures and 46 patients without seizures were analysed. Overall, the nonexpert ICU physicians failed to identify recordings obtained from patients with seizures reliably, when compared with clinical diagnosis and the single-channel EEG results (mean sensitivity 40%, range 40-60%; mean specificity 89%, range 87-93%). Agreement between observers was high for the cases with seizures ( ĸ = 0.80 ± 0.13). Patients who suffered status epilepticus during the recordings were difficult to identify by most raters. CONCLUSION: Recording of aEEG without access to the raw EEG data is not a reliable diagnostic tool for the identification of epileptic seizures in the hands of nonexpert ICU physicians.

A comparison between over-the-head and standard cardiopulmonary resuscitation performed by two rescuers: a simulation study.

BACKGROUND: In cardiopulmonary resuscitation (CPR) of a patient with an unsecured airway performed by two health care professionals, two methods are possible: 1) Standard CPR according to the guidelines, with one rescuer performing chest compressions from the side and the other rescuer performing ventilations from over the head of the patient. Additional tasks (like attaching the electrocardiogram and defibrillator) must be performed by the second rescuer during the time between ventilations. 2) Over-the-head CPR, with one rescuer performing chest compressions and ventilations from over the head and the other rescuer performing additional tasks. OBJECTIVES: The aim of this study was to compare the quality of CPR achieved by the two methods. METHODS: After a standardized theoretical introduction and practical training, 106 medical students with limited knowledge and training in CPR participated in this randomized crossover study. Students performed a 2-min CPR test of standard CPR in both positions and over-the-head CPR alone on a manikin. RESULTS: Standard CPR led to a significantly shorter hands-off-time over a 2-min interval than over-the-head CPR (median 25 s [interquartile range (IQR) 22-26 s] vs. 38 s [IQR 36-43 s], respectively, p < 0.001), and significantly more chest compressions (167 [IQR 158-176] vs. 142 [IQR 132-150], respectively, p < 0.001), more correct chest compressions (72 [IQR 11-136] vs. 45 [IQR 13-88], respectively, p = 0.004), inflations (10 [IQR 10-10] vs. 8 [IQR 8-8], respectively, p < 0.001), and correct inflations (5 [IQR 2-7] vs. 3 [IQR 1-4], respectively, p < 0.001). CONCLUSIONS: In the case of a two-professional-rescuer CPR scenario, standard CPR enables a quantitatively better resuscitation than over-the-head CPR.

Bivalvulidan (Myxozoa: Myxosporea) parasites of damselfishes with description of twelve novel species from Australia's Great Barrier Reef.

Bivalvulidan parasites from the gall bladder of 31 species of damselfishes (family Pomacentridae) were examined for their taxonomic identity and their relatedness to other species of myxozoans. This paper describes 11 novel ceratomyxid species and a novel Myxidium sp. Each species is characterized morphologically and small subunit (SSU) rDNA sequences were used in molecular phylogenetic analyses. Five pomacentrid species were found to harbour multiple infections of bivalvulidan species. One species of Ceratomyxa and Myxidium were found to infect more than a single species of damselfish. Phylogenetic analyses revealed there has been no radiation of ceratomyxids that can be associated with the fish host taxon and that Myxidium queenslandicus n.sp. was more closely related to Zschokkella mugilis and Ellipsomyxa gobii than other members of the genus Myxidium.

Upregulation of interleukin-4 and IFN-gamma expression by IFN-tau, a member of the type I IFN family.

Trophoblast interferon-tau (IFN-tau) is a new member of the type I IFN family that is produced in large quantities by the ruminant conceptus. Like other type I IFN, IFN-tau inhibits viral replication and activates natural killer (NK)-mediated cytotoxicity. In mice and humans, type I IFN enhances type 1 T helper (Th) cell responses, but the effects of type I IFN, including IFN-tau, on cytokine expression by bovine Th cells have not been described. The present study determined the effects of IFN-tau on interleukin-4 (IL-4), IFN-gamma, and IL-10 expression by antigen-specific, CD4+ T cell lines derived from cattle immune to either Babesia bovis, Babesia bigemina rhoptry-associated protein-1, or Anaplasma marginale. IFN-tau upregulated IFN-gamma secretion and steady-state levels of IFN-gamma and IL-4 mRNA by cell lines cultured for 3-6 weeks. In contrast, the steady-state levels of IL-10 mRNA were either not changed or inhibited at these times. Similar effects were obtained with human IFN-alpha. Comparison of the quantities of IFN-gamma, IL-4, and IL-10 transcripts in IFN-tau-treated or IFN-alpha-treated cultures revealed that even though IFN-gamma was the predominant cytokine expressed by all T cell lines, both IFN-gamma and IL-4 steady-state transcript levels were upregulated by a comparable degree. Thus, these studies demonstrate that IFN-tau is an immunomodulatory cytokine that promotes enhanced IL-4 and IFN-gamma responses by effector T cells but not, strictly speaking, Thl-biased responses in cattle. These results indicate the potential use of this cytokine as an adjuvant in ruminants to boost cell-mediated immune responses.

Cowdria ruminantium antigens of around 15 kDa are potent inducers of IFN-gamma.

Cellular responses induced in two Creole goats by vaccination with killed Cowdria ruminantium (Cowdria) were confirmed by IFN-gamma production and interleukin-2 receptor (IL-2R) expression. Both CD4+ and CD8+ but not WC1+ T cells showed a substantial increase in cell surface expression of IL-2R molecules in response to whole Cowdria lysate. Cowdria (Welgevonden strain) proteins were fractionated using continuous-flow electrophoresis and tested for their ability to induce IFN-gamma production by PBMC collected three weeks after the first inoculation and one week after the booster injection. Pooled fractions of around 15, 22, and 24 kDa were found to induce significant IFN-gamma production in both vaccinated animals on one of the two occasions. Antigens of around 15 kDa induced substantially higher IFN-gamma production than any other fractions in both animals. These pilot experiments pave the way towards the identification of proteins/genes that have potential for the development of a recombinant vaccine against heartwater.

Low molecular weight proteins of Cowdria ruminantium (Welgevonden isolate) induce bovine CD4+-enriched T-cells to proliferate and produce interferon-gamma.

An important objective in vaccination strategies is to activate lymphocytes with particular effector functions. Cellular immunity and the type I cytokine IFN-gamma have been implicated in protective immunity to heartwater. Furthermore, low molecular weight proteins of Cowdria ruminantium have been shown to induce peripheral blood mononuclear cells to proliferate. To determine which lymphocyte subset responds when stimulated with fractionated C. ruminantium proteins, specific short-term lymphocyte cultures were established from cattle immunized with the Welgevonden isolate. Four cattle were immunized, two by infection and treatment and two with inactivated organisms. Cell surface phenotypic analysis of the cultures indicated that CD4+ lymphocytes were enriched over time. This coincided with increased antigen-specific proliferation and IFN-gamma production. Proteins of molecular weights 13-18kDa induced the CD4+-enriched T-cell cultures, derived from each of the animals, to proliferate and produce IFN-gamma. Although the two groups of cattle were immunized differently, their lymphocytes responded similarly. These results extend previous findings by identifying the responder cells as being predominantly IFN-gamma producing CD4+ lymphocytes. This cytokine has been implicated in immunity to the parasite. The low molecular weight proteins that induced CD4+ lymphocytes to proliferate and produce IFN-gamma are therefore likely to be important in protection against heartwater and may have a role in vaccine development.

Experiences with linked birth and infant death certificates from the NIMS project.

The National Infant Mortality Surveillance (NIMS) project aggregated data provided by 53 vital statistics reporting areas--50 States, New York City, the District of Columbia, and Puerto Rico (subsequently called States)--from their files of linked birth and death certificates and compared individual States' total infant mortality experiences for the 1980 birth cohort by age at death, race, birth weight, and plurality. Therefore, it was essential to achieve maximum uniformity among the separate data sets and to specify when this uniformity could not be obtained. In working with these multiple sources, we identified five key issues that relate to data from linked birth and death certificates: Variations in definitions of variables are often embedded in data that have been gathered from several independent sources. (For NIMS, the sources were 53 reporting areas and the National Center for Health Statistics.) Variations in States' linking procedures--these are based on an individual State's primary purpose for linking the data--affect the completeness and comparability of the 1980 resident birth cohorts used for NIMS. Variations in the recording of some pregnancy outcomes as fetal deaths or live births are known to be a problem in vital statistics data that particularly affects data for events among infants weighing less than 500 g at birth. Ambiguities occur frequently in unknowns or zero values. For NIMS this effect was most pronounced for the pregnancy history variables. Examination of the values reported for unknown or zero categories helps in uncovering problems with and improving quality of data. (e) Analysis from a new perspective may reveal unexpected data problems. These problems tend to surface only during a reexamination of underlying data that is prompted by unusual findings.Continued alertness to these issues may improve further the quality of data in files of linked birth and death certificates and assure the integrity of analysis based on these data.

PIP: The authors analyze the quality of data in the files of linked birth and death certificates from the U.S. National Infant Mortality Surveillance (NIMS) project. The project compared individual states' total infant mortality experiences for the 1980 cohort. Uniformity among the separate data sets is considered essential. Variations in definitions, variations in states' linking procedures, variations in the recording of some pregnancy outcomes, ambiguous treatment of unknowns or zero values, and unexpected data problems are discussed

Health care improvement and cost reduction opportunities in hypertensive Medicaid beneficiaries.

Hypertension and its complications are more frequent and occur about a decade earlier in life among high-risk groups, especially in the Southeast. Moreover, socioeconomic status is inversely related to hypertension and cardiovascular complications. Low-income, young and middle-aged adults living in the Southeast may be at especially high risk. Data on inpatient admissions among hypertensive Medicaid beneficiaries living in this region may provide insights on the burden of hypertension-related disease and on opportunities for successful intervention. A study of hospitalization rates and costs among 44,440 hypertensive Medicaid beneficiaries in South Carolina from 1993-1996 showed that 16,883 (38%) were continuously enrolled in Medicaid. Of this group, 63% were African American and 74% were women. Among the continuously enrolled patients, 7637, or about 45%, were hospitalized during the 4-year period. These 7637 individuals accounted for 20,698 hospital admissions, i.e., 2.7 admissions per person, over the 4-year interval. Nearly two thirds of the hospitalizations included a cardiovascular or renal diagnosis. Hospital claims paid reached nearly $90 million for the 7637 hypertensive Medicaid recipients during the 4-year period. Among patients discharged from the hospital with congestive heart failure, 33% filled a prescription for an angiotensin-converting enzyme inhibitor within 90 days; 13% of patients discharged with an acute myocardial infarction filled a prescription for a beta blocker within 90 days. The data confirm that hypertensive Medicaid beneficiaries in the Southeast are hospitalized at high rates. Cardiovascular and renal morbidity account for the majority of the inpatient admissions. The findings suggest that the application of evidence-based guidelines would improve health, avoid cost, and reduce racial disparities in health outcomes.

Identification of sensory blockade by somatosensory and pain-induced evoked potentials.

BACKGROUND: To date, the anesthesia-induced blockade of nociceptive inputs is insufficiently reflected by commercially available electroencephalographic depth-of-anesthesia monitors. The aim of the current study was to evaluate the potential of somatosensory (SSEP) and intracutaneous pain evoked (iSEP) potentials during remifentanil and propofol anesthesia as electroencephalographic indicators of the nociceptive blockade. METHODS: Ten healthy men were investigated in a double-blind crossover design during three sessions with remifentanil, propofol, and placebo administration. All dosages were increased in a step-by-step mode. SSEP and iSEP recordings were performed followed by subjective pain ratings and measurement of level of sedation (modified Observer's Assessment of Alertness and Sedation Scale). Changes from baseline in evoked potential components, pain ratings, and sedation scale were assessed by Bonferroni-Holms-corrected Wilcoxon tests. RESULTS: Pain ratings were significantly reduced by remifentanil. Sedation scale was significantly reduced by propofol. Early SSEP components were not affected by medication. The amplitudes of the long latency SSEP components increased significantly with remifentanil, decreased with propofol, and did not change with placebo. The amplitudes of long latency components of the iSEP decreased significantly with both remifentanil and propofol and did not change with placebo. CONCLUSION: Long latency components of the SSEP are differently affected by remifentanil and propofol administration. Further studies are needed to clarify whether they can serve as a specific indicator of the nociceptive blockade during anesthesia.

Asymmetric and axisymmetric constant curvature liquid-gas interfaces in pulmonary airways.

Airway closure and gas trapping can occur during lung deflation and inflation when fluid menisci form across the lumina of respiratory passageways. Previous analyses of the behavior of liquid in airways have assumed that the airway is completely wetted or that the contact angle of the liquid-gas interface with the airway wall is 0 degrees, and thus that the airway fluid forms an axisymmetric surface. However, some investigators have suggested that liquid in the airways is discontinuous and that contact angles can be as high as 67 degrees. In this study we consider the characteristics of constant curvature surfaces that could form a stable liquid-gas interface in a cylindrical airway. Our analysis suggests that, for small liquid volumes, asymmetric droplets are more likely to form than axisymmetric toroids. In addition, if the fluid contact angle is greater than 13 degrees, asymmetric droplets can sustain larger liquid volumes than axisymmetric toroids before collapsing to form menisci. These results suggest that (1) fluid formations other than axisymmetric toroids could occur in the airways; and (2) the analysis of the behavior of fluids and the development of liquid menisci within the lungs should include the potential role of asymmetric droplets.

The peer-managed small group versus the rehabilitation model of treatment of chronic patients.

The Fairweather small-group model, developed some 20 years ago, has been proven to be an effective form of treatment for chronic patients who have spent long years in institutions. However, there have been no recent evaluations of how small-group programs work compared with contemporary rehabilitation programs and how effective they are with the "new chronic patient" recently described in the literature. In a study of such patients at the Florida Mental Health Institute in 1977, the authors compared matched patients in a small-group program and a rehabilitation therapy program on measures of self-concept, perception of kind and degree of help received, and recidivism rate. They found that patients in the small-group program spent significantly less time in treatment. Moreover, the small-group program was effective in reducing recidivism over an 18-month period and was less expensive than the rehabilitation therapy program.

Cooperative Cardiovascular Project.

This national project evaluated elements of care for patients admitted for acute myocardial infarction. Opportunities for improving processes of care, especially in the use and timing of aspirin and thrombolytics, were identified. Additional data regarding other quality indicators is available. It is hoped that this data can be used to help create or incorporate changes in existing AMI protocols, ultimately improving care and outcomes for these patients.

Monoclonal antibody characterization of reference isolates of different serogroups of Haemophilus paragallinarum.

Previously, a panel of five monoclonal antibodies (Mabs) was used to study the antigens of strains 0083, 0222 and Modesto of Haemophilus paragallinarum and marked antigenic differences were noted. To establish if these differences were serogroup specific, more reference strains were examined with these Mabs. It was not possible to detect any relationship between the antigens recognized by the Mabs and the serogroup of the reference strain. None of the Mabs produced reacted with the haemagglutinins of the reference strains. The F1 Mab detected an outer membrane protein of 39 kDa, while the V1 Mab detected a lipopolysaccharide of between 13.8 to 14 kDa. Mabs VF1 and VF2 both recognized antigens of 39 kDa of unknown chemical nature and with extremely low frequency of occurrence among strains and isolates. The VF3 Mab detected a lipopolysaccharide with multiple bands at 37 to 39 kDa, which broke down after freezing and thawing to multiple bands of 29 to 32 kDa. These results imply that the haemagglutinins, which are the major typing and protective antigens remain undetected by this panel of Mabs.

Prophylactic antibiotic project.

This project evaluated the use of prophylactic antibiotics within two hours prior to selected surgical procedures. Even with knee arthroplasty, for which there is essentially universal agreement on the need for prophylactic antibiotics, there is room for improvement in antibiotic delivery. This is true both in the percent of patients receiving antibiotics and the timeliness of administration. Although there is some difference of opinion about the advisability of prophylactic antibiotics for certain procedures, the preponderance of recent literature advocates its use and this is a quality indicator evaluated by JCAHO.

Pneumonia I and Pneumonia II Projects.

The need for timely and efficient treatment is assuming even greater significance, with pneumonia discharges increasing from 5,862 in 1992 to 7,870 in 1994. These two projects, involving a total of 13 hospitals, evaluated the timeliness of antibiotic administration for pneumonia patients. Baseline data revealed opportunities for improving process of care at all hospitals. After implementation of improvement plans, the majority of hospitals increased the percentage of patients receiving antibiotics within four hours of admission. This evaluation of the antibiotic delivery system can also be adapted to other diagnoses and medications.