Continuous ventilation during intubation through a supraglottic airway device guided by fiberoptic bronchoscopy: a observational assessment.

INTRODUCTION: supraglottic airway devices remain, despite advances in video laryngoscopy, important tools in the management of unexpected difficult airways. Intubation through a functioning supraglottic airway device with the aid of a fiberoptic bronchoscope is a well-known technique usually performed in apnoea. With a simple modification, the patient can be ventilated during this procedure. METHODS: In this observational study, Tracheal intubation Assisted by Bronchoscopy And Sad during Continuous Oxygenation (TABASCO) was performed as part of department training routine in 26 elective, fasted patients. A supraglottic airway device was used as a conduit for an endotracheal tube. RESULTS: All patients were easily intubated and ventilation was maintained during the procedure. The gap between the outer diameter of the fiberoptic bronchoscope and the inner diameter of the endotracheal tube was more than 2 mm in 25 of 26 patients. Effective ventilation was confirmed by clinical signs, capnography and pressure-volume curves. No signs of airtrapping occurred. DISCUSSION: No adverse events were observed during this form of airway management in this small series of elective and fasted patient when performed by an anaesthesiologist experienced in fiberoptic intubation. A gap between fiberoptic bronchoscope and endotracheal tube inner lumen seems to be prerequisite for easy ventilation through the supraglottic airway. In trained hands, this technique can be a means to secure an airway with an intubating bronchoscope without pausing ventilations. A prerequisite for this is a well-functioning supraglottic airway device.

From adaptive licensing to adaptive pathways: delivering a flexible life-span approach to bring new drugs to patients.

The concept of adaptive licensing (AL) has met with considerable interest. Yet some remain skeptical about its feasibility. Others argue that the focus and name of AL should be broadened. Against this background of ongoing debate, we examine the environmental changes that will likely make adaptive pathways the preferred approach in the future. The key drivers include: growing patient demand for timely access to promising therapies, emerging science leading to fragmentation of treatment populations, rising payer influence on product accessibility, and pressure on pharma/investors to ensure sustainability of drug development. We also discuss a number of environmental changes that will enable an adaptive paradigm. A life-span approach to bringing innovation to patients is expected to help address the perceived access vs. evidence trade-off, help de-risk drug development, and lead to better outcomes for patients.

A simple and rapid flow cytometric method for routine assessment of baker's yeast uptake by human polymorphonuclear leukocytes.

A new method for measuring uptake of baker's yeast (BY) by human polymorphonuclear leukocytes (PMN) using flow cytometry is described. The method correlates excellently with the visual method, is reproducible and provides a means for investigating the early phases of the phagocytic process as well as the phagocytic capacity of PMN. This quick and accurate method allows the counting of large numbers of cells, and monitoring of the process of particle uptake and has a considerable potential in the routine assessment of polymorph function in various clinical situations.

Lymphocyte responsiveness to lectin and myelin antigens in canine distemper infection in relation to the development of demyelinating lesions.

Eleven dogs were experimentally infected with canine distemper virus and studied for periods of up to 63 days post-inoculation. The responsiveness of lymphocytes in vitro toward phytohemagglutinin, myelin basic protein and galactocerebroside was tested at regular intervals during the course of infection by means of [3H]thymidine incorporation and flow cytometry. All dogs developed a marked decrease of lymphocyte responsiveness toward phytohemagglutinin. Four dogs recovered rapidly from the immunosuppression and did not develop demyelination or had only mild lesions, while two others failed to recover at all and developed severe non-inflammatory demyelinating lesions. The remaining dogs exhibited a slow or partial immune recovery and had various degrees of inflammatory demyelination. Lymphocytes from 2 dogs with demyelination and 2 dogs without myelin lesions responded to myelin antigens. The findings indicate that the degree of immunosuppression in canine distemper virus infection may determine the type of demyelination and autoimmune reactions that occur during the inflammatory stage of demyelination may be epiphenomena.

Human lymphocyte proliferation. I. Correlation between activated and proliferating T-lymphocytes.

The response of human peripheral blood lymphocytes to Con A and PHA has been analyzed by [3H]thymidine incorporation and cytofluorometry. Using the latter method, it is possible to quantitate the number of cells in the G0 phase (normal RNA and DNA content) and in the G1 phase (elevated RNA, but normal DNA content). A very high correlation is found between numbers of Con A or PHA-induced G1 cells and [3H]thymidine incorporation in healthy donors. This high correlation is found when culture medium is enriched with 10% autologous plasma or 10% AB-serum. The use of a recently developed defined serum-free medium (RPMI 1640 with albumin, alanine, transferrin, sodium selenite and zinc chloride), however, suggest that donors can be divided into two groups according to different medium requirements for PHA-stimulated lymphocytes. Because several immunoregulatory mechanisms at the level of T-lymphocytes take place in the G1 phase, it can therefore be expected that cytofluorometric analyses of lymphocytes in the various cell cycle phases may improve the interpretation of altered lymphocyte response to lectins and antigens.

Age-related changes of mitogen responsiveness in different lymphoid organs from outbred NMRI mice.

Lymphocytes from spleen, thymus and lymph nodes from individual young adult (3--4 months) and aged (26--30 months) NMRI mice were stimulated with the mitogens Con A, PHA and LPS. 24 hours later, the number of cell with increased RNA-content (G1 cells) was determined by cytofluorometry. In parallel the 3H-thymidine incorporation after 48 hours was measured for the same cell samples. Aged animals in average produced less G1 cells and incorporated less 3H-thymidine as compared to young adults. By calculating the 3H-thymidine incorporation per G1 cell, the proliferative capacity of mitogen-induced G1 cells can be estimated. These ratios are lower in aged mice as compared to young adult, suggesting that in these animals not only less cells can be activated as measured by cytofluorometry, but also from these activated cells again fewer continue the cell cycle by initiating DNA-synthesis. In response to Con A and PHA, aged mice in average produce less G1 cells in all of the three lymphoid organs tested. In response to LPS, however, the young adult produced only few G1 cells in lymph nodes and practically none in thymus, whereas in aged animals a considerable number of G1 cells was found in both organs. Corresponding results were found for the 3H-thymidine incorporation. These results indicate that in addition to the reduction of the mitogen-response an age-related change in the distribution of mitogen-responsive cells in the different lymphoid organs takes place.

Aging and immunity: decrease in interleukin-2 production and interleukin-2-dependent RNA-synthesis in lectin-stimulated and murine spleen cells.

The RNA-content of G1 cells in lectin-stimulated spleen cell cultures of young and aged NMRI mice was determined by flow cytometry. In spleen cells of aged mice a preferential decrease of G1 cells with a high RNA-content, so-called G1b cells, was found. Since, as shown in a previous report, only cells with a high RNA-content are able to proliferate and the passage of low (G1a) to high (G1b) RNA-content is interleukin-2(IL-2)-dependent, the ability of young and old spleen cells to produce IL-2 was tested. In old spleen cells a diminished production of IL-2 was found. Addition of external IL-2, however, did not increase the proliferative capacity of old spleen cells, nor did it induce more G1b cells. Thus spleens of aged mice contain cells, which can be activated by lectin, but then fail to respond to IL-2. Both decrease in IL-2 production and receptivity for IL-2 may contribute to the diminishing immune response in aging individuals.

Evaluation of murine thymocyte stimulation using a defined culture medium.

The ability of RPMI 1640 enriched with FCS or AATSZ (L-alanine, BSA, human transferrin, zinc chloride, and sodium selenite) to support mitogen-induced activation (G0-G1 shift) and proliferation (G1-S shift) of thymocytes has been investigated. The two culture media were found to be equally supportive. In terms of viability, differences were detected in the number of recovered viable cells, but this could be related to alterations in adherent properties, rather than viability of the cells. For the examination of a PHA-induced proliferation, IL-1-containing suppernatants, deriving from normal or induced peritoneal macrophages, were prepared. The supportive capacity of these preparations showed no significant difference between AATSZ and FCS. Despite the excellent supportive capacity for the mitogen-stimulated thymocyte cultures, the AATSZ medium was not able to support all established cell lines tested. A T cell (MOLT 4F) and a macrophage cell line (SK 1) grew equally well in AATSZ- and FCS-enriched medium, but a B cell (U 266) and a null-cell line (Reh) did not proliferate at all. When cells from the latter two lines were cultured in AATSZ medium, they did not complete the RNA-synthesis required for DNA-synthesis, as judged by cytofluorography. From the experiments presented it is concluded that the AATSZ medium offers several advantages, such as easy standardization of culture conditions, and no essential disadvantages for studying mitogen-stimulated thymocytes in vitro. On the other hand, some lymphoid cell lines do require culture conditions that the AATSZ medium cannot provide.

Validation of the Danish Birth Registration.

We assessed validity and reliability of data on four serious pregnancy complications and gestational age in two national registers, the Medical Birth Register (MBR) and the National Register of Hospital Discharges (NRHD). From a cohort of all women in Denmark who gave birth to their first and second singleton infant in 1982-1987, a review was made of a selected sample of 1662 medical records. Regarding registration of pregnancy complications, there was good agreement (kappa above 0.6) between medical records and the registers, and between the registers. However, there was a tendency toward understatement evidenced by low sensitivity of three of four pregnancy complications. The level of agreement (43%) for length of gestation was disappointing. The number of systematic and nonsystematic errors indicate that there was about 52% more singleton preterm deliveries in Denmark in 1982 than previously reported (6.9% instead of 4.5%). It is concluded that the validity of the Danish birth registers should be improved by explicit definitions, increased use of raw data, and data collection by motivated professionals at birth.

Life table analysis of infant mortality and feto-infant mortality distributed on causes of death in Denmark 1983-1987.

The survival function of 263,322 singletons of the 1983-1987 Danish birth cohorts (262,159 liveborn and 1163 stillborn babies) with mortality distributed on functional groups of underlying causes of death is presented in two graphic forms on the basis of Kaplan-Meier estimates. About half of all first-day deaths in liveborn babies occurred during the first 4 hours. More than half of all first-week deaths happened during the first day. More than half of all deaths from 31 weeks to 76 weeks after the first day of the last menstrual period (LMP) were either fetal deaths prior to the onset of labour unexplained by fetal factors or unexplained sudden infant death syndrome (SIDS) deaths. Graphic presentation of feto-infant mortality distributed on functional cause-of-death groups improved the expression of the relative contribution and timing of the different causes of deaths. Despite a high autopsy rate and a uniform coding practice the distribution on causes of deaths from register data should be interpreted with caution. Full use of the feto-infant approach is only achieved with data which include late abortions. Thus the feto-infant approach is of special interest in countries which have registers of live births and fetal deaths from week 22 of gestation or earlier. The integration of the life table approach and analysis of underlying causes of deaths should be further explored as a way of utilizing vital statistic databases for the evaluation of perinatal care.

Idiopathic preterm deliveries in Denmark.

OBJECTIVE: To characterize and quantify various demographic factors in idiopathic preterm delivery. METHODS: All women with a permanent address in Denmark and a singleton pregnancy who gave birth to a preterm infant in 1982 (N = 51,851) were included. The material was obtained by a linkage of the Medical Birth Register and the National Register of Hospital Discharges, using personal identification numbers. RESULTS: The incidence of singleton preterm delivery was 4.5% (N = 2330), of which 67% (N = 1557) were idiopathic. The neonatal mortality rate was significantly lower with idiopathic than with indicated preterm birth. Following stepwise logistic regression analysis, age under 20 (adjusted odds ratio [OR] 1.63, 95% confidence interval [CI] 1.07-2.47; P < .03), age above 30 (adjusted OR 0.74, 95% CI 0.60-0.90; P < .004) and being married (adjusted OR 0.63, 95% CI 0.43-0.94; P < .03) correlated with idiopathic preterm birth. CONCLUSION: Idiopathic preterm birth is more common in single, young women and is associated with a lower neonatal mortality rate than indicated preterm birth.

Increased risk of preterm birth in women with cervical conization.

OBJECTIVE: To determine the relation between cervical conization and preterm birth. METHODS: All Danish women with singleton pregnancies who gave birth to their first infant in 1982 and second infant during the time period 1982-1987 were included in a register-based cohort study. Information on pregnancy outcome and cervical conization in 1977-1987 was obtained from the Medical Birth Register and the National Register of Hospital Discharges. RESULTS: In a cohort of 14,233 women, 170 had cervical conization. Thirty-four had cervical conization before the first delivery, 62 between the first and the second, and 74 after the second delivery. Women with cervical conization had a significantly higher risk of preterm birth. In addition, women with subsequent cervical conization had a higher risk of preterm birth in previous pregnancies. However, the risk of preterm birth was higher in women with previous than with subsequent cervical conization. CONCLUSIONS: Cervical conization is correlated with preterm birth. Because women with subsequent cervical conization have an increased risk of preterm birth in preceding pregnancies, factors other than the surgical intervention may contribute to the significantly increased risk of preterm birth.

Implications of idiopathic preterm delivery for previous and subsequent pregnancies.

OBJECTIVE: To describe the relationship between pregnancy complications and fetal outcome in first and second pregnancies, focusing on idiopathic and indicated preterm birth of singleton infants in either pregnancy. METHODS: Included in the study were 13,967 women in Denmark who gave birth to their first singleton infant in 1982 and a second infant in 1982-1987. Information on pregnancy and birth was obtained by linking the National Medical Birth Register and the National Register of Hospital Discharges, based on personal identification numbers. RESULTS: The risk of a preterm second birth in women with idiopathic and indicated preterm first birth did not differ significantly (15.2 and 12.8%, respectively). However, women with idiopathic preterm birth in the first pregnancy tended to repeat idiopathic preterm birth twice as often as women with indicated preterm birth repeated indicated preterm birth (11.3 versus 6.4%). Adjustment by logistic regression analysis for other risk factors for preterm birth did not influence the relative risk (6.0 before 32 weeks and 4.8 for 32-36 weeks) of a second preterm birth after a first preterm birth. Women with idiopathic preterm delivery in their first and second pregnancies gave birth to infants with lower birth weight than in previous or subsequent pregnancies. Emergency cesarean delivery in a first term pregnancy was a risk factor for subsequent idiopathic preterm birth. CONCLUSION: Idiopathic preterm birth is associated with emergency cesarean delivery at term in previous pregnancies and infants with lower birth weight in previous and subsequent pregnancies.

Enhanced granulocyte function in a case of chronic granulocytic leukemia in a dog.

Chronic granulocytic leukemia is a rare myeloproliferative disorder in dogs. The present study investigated various functions of leukemic granulocytes in a dog that presented with thrombocytopenic purpura, anaemia and a classical leukemic hemogram. All analyses were performed in parallel with a control dog. Purification of the leukemic granulocytes by density gradient centrifugation revealed three neutrophil and neutrophil precursor populations with different densities. Comparison of cell morphology and density showed that cell density increased with increasing maturity. The control dog possessed only one neutrophil population, with a density greater than 1.077. Analysis of cellular contents of the granular enzymes, elastase, myeloperoxidase and lysozyme showed that leukemic neutrophils were quantitatively markedly different from normal neutrophils with respect to enzyme activities. There were no major differences between leukemic and normal cells as regards aggregatory and migratory responses to different stimuli. The phagocytic capacity of the leukemic cells, however, was dramatically increased compared with the control, and exceeded all previously encountered responses in the assay employed. In a similar fashion, superoxide generation and secretion of elastase and lysozyme in response to zymosan and phorbol myristate acetate were substantially higher than in the control dog. Priming of cell function to a level exceeding that normally attainable in neutrophils appears to have taken place in peripheral blood of the leukemic dog. The only endogenous mediator known to prime neutrophil functions to the extent seen in the present case is the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF), which is intimately involved in regulation of myelopoiesis in mammals. On the basis of the enzymological and functional findings in the leukemic dog, we hypothesize that a lactoferrin deficiency in leukemic neutrophils leads to enhanced GM-CSF synthesis, which is ultimately the cause of the observed cellular hyperresponsiveness and contributes to the monocytosis seen in the patient.

Interleukin 1- and 2-like activities in the dog.

Canine adherent and non-adherent peripheral blood leukocytes and spleen cells were examined for their ability to produce soluble factors with Interleukin 1- and 2- (IL-1 and IL-2) like activities. For this purpose, three conventional assay systems were used: (a) proliferation on an IL-2-dependent murine cytotoxic T-lymphocyte cell line, (b) enhancement of PHA-induced murine thymocyte proliferation and (c) proliferation of lectin-primed canine peripheral blood lymphocytes (PBL). Only the latter two types of cells respond to IL-1, whereas all three types respond to IL-2. Both types of factors were produced and the kinetics of their release/production were found to be identical to those of human PBL. Results suggested that species-related differences existed. Canine interleukin-containing supernatants had higher titers than murine interleukin-containing supernatants when analyzed on canine lymphocytes, and the reverse was found if murine target cells were used.

Canine lymphocyte cultures in vitro: evaluation of peripheral blood lymphocyte response to mitogens.

Lymphocytes from dog peripheral blood have been stimulated in vitro with 3 different mitogens (Con A, PHA and PWM). Culture medium was RPMI 1640 enriched with either autologous plasma, fetal calf serum of a newly described defined serum substitute. In such cultures the number of surviving and activated cells was measured by cytofluorometry and the proliferation was assessed by thymidine incorporation. In unstimulated cultures, up to 70% of all cells had disappeared (died) during the first 42 hours of incubation, whereas the number of viable cells was reduced to 50-60% in mitogen stimulated cultures. Of the surviving lymphocytes, between 25-40% of the cells appeared to have an elevated RNA-content (activated or G1 cells). By comparison between thymidine incorporation and number of mitogen induced G1 cells, a very high correlation was found (r=0.92). However, the Slope of the regression line was much lower than expected. The low thymidine incorporation per activated cell was primarily related to the high cell death and a resulting dilution of tritiated thymidine. Indeed, preliminary results suggested that the same thymidine incorporation per G1b cells could be obtained if peripheral blood lymphocytes were washed immediately before pulsing as could be obtained with lymph node cells without washing.

Technical aspects of low 3H-thymidine incorporation by mitogen stimulated canine peripheral blood lymphocytes in vitro.

The value of [3H]-thymidine incorporation as a measurement for mitogen induced proliferation of dog peripheral blood lymphocytes (PBL) has been examined. The cells were cultured in RPMI 1640, enriched with 10% autologous plasma for 48 hours at 37 degrees C, 5% CO2 and 95% relative humidity. Under these conditions a great variability in [3H]-thymidine incorporation was observed. By analysis of CPM and number of activated cells (G1), it was found that comparable number of G1 cells were generated in human and dog PBL. Also, the membrane transport of thymidine was very similar for lymphocytes of the two species. Nevertheless, a low [3H]-thymidine incorporation by dog PBL was frequently seen, and this phenomenon could be related to a release of soluble substance(s) within the cultures. When the cultured cells were washed and resuspended in fresh medium immediately before pulsing, the expected CPM per G1 cell could be obtained. Since it has been described in the literature that macrophages can produce cold thymidine in macrophage enriched lymphocyte cultures, the in vitro response of non-adherent dog PBL was analyzed. Mitogen stimulation of such non-adherent cells resulted in CPM per G1 cells very similar to those obtained with washed cells. Based on these data, it is suggested that the production of cold thymidine might be one of the technical problems related to cultures of lectin stimulated dog PBL in vitro and it should be taken into consideration, if [3H]-thymidine incorporation is used as the only measure of lymphocyte proliferation.

Development and validation of an improved enzyme-linked immunosorbent assay for the detection of thyroglobulin autoantibodies in canine serum samples.

An enzyme-linked immunosorbent assay to detect thyroglobulin autoantibodies (TGAB) in canine serum was developed and validated. The test result for each sample was derived from the optical density readings (OD) and expressed as an Ab-score(%) calculated from three in-house calibrators. The assay specifically detected TGAB as judged from lack of response in the assay after samples had been incubated with specific antigen. Intra- and interassay coefficients of variation ranged from 2.0-4.9% and 4.6-9.9%, respectively. The detection limit, an Ab-score of 5.6%, was close to the median Ab-score of 10% observed in healthy dogs (n = 132). The median Ab-score of dogs with primary hypothyroidism and lymphocytic thyroiditis (n = 11), skin diseases (n = 35), and non-thyroidal diseases (n = 63) was 340%, 12%, and 8%, respectively. The prevalence of TGAB in hypothyroid dogs with lymphocytic thyroiditis (sensitivity) was 91% (95% confidence limits: 59%-99%). In dogs with dermatological diseases without lymphocytic thyroiditis the prevalence of TGAB was 3% corresponding to a specificity of 97% (95% confidence limit: 85%-100%). In dogs with non-thyroidal diseases and healthy dogs the prevalence of TGAB was 5% and 6%, respectively. The diagnostic accuracy of serum TGAB was evaluated by subjecting the data from 11 dogs with lymphocytic thyroiditis and 35 control dogs without lymphocytic thyroiditis to receiver-operating characteristic curve analysis. The area under the receiver-operating characteristic curve (W = 0.966; 95% confidence limit 87%-100%) was significantly higher than that of a worthless test (0.5) (P < 0.0001), thereby indicating that serum TGAB measurements distinguished between dogs with and without lymphocytic thyroiditis.