Increase in impaired motor coordination in six-year-old German children between 1990 and 2007.

AIM: To evaluate changes in prevalence of impaired motor coordination among 6-year-olds of a geographically defined area in Germany between the years 1990 and 2007. METHODS: Data from the obligatory school entrance examinations in the German state of North Rhine Westphalia between the years 1990 and 2007 were used. The number of children assessed per year varied from 81 517 to 124 086. The classification of impaired motor coordination was based on the combination of standardized screening and physicians' clinical impression of need of treatment. Logistic regression modelling was performed to evaluate the changes in prevalence of impaired motor coordination. RESULTS: Between 1990 and 2007, the prevalence of impaired motor coordination rose from 2.5% to 8.9% in boys and from 0.8% to 3.6% in girls. As the standard error of these percentages is below 0.15%, the changes are highly statistically significant. CONCLUSION: The prevalence of impaired motor coordination tripled during the last decades in North Rhine Westphalia. This may imply that the prevalence of Developmental Coordination Disorder also increased. Factors that may explain the increasing prevalence include the increase in surviving preterm infants, increasing parental age at child birth, maternal and child obesity and decreasing child mobility.

The Groningen ART cohort study: ovarian hyperstimulation and the in vitro procedure do not affect neurological outcome in infancy.

BACKGROUND: Due to the growing number of children born following assisted reproduction technology, even subtle changes in the children's health and development are of importance to society at large. The aim of the present study was to evaluate the specific effects of ovarian hyperstimulation and the in vitro procedure on neurological outcome in 4-18-month-old children. METHODS: In this prospective assessor-blinded cohort study, we included singletons born following controlled ovarian hyperstimulation in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) (COH-IVF; n = 68) or modified natural cycle-IVF/ICSI (MNC-IVF; n = 57) or naturally conceived singletons of subfertile couples (NC; n = 90). Children were assessed with standardized, age-specific and sensitive neurological assessments (TINE and Hempel assessment) at 4, 10 and 18 months. Neurological examination resulted in a neurological optimality score (NOS), a fluency score and a clinical neurological classification. Fluency of movements is easily affected by neurological dysfunction and is therefore a sensitive measure for minimal changes in neuromotor development. RESULTS: The NOS and the fluency score were similar in COH-IVF, MNC-IVF and NC children. None of the children showed major neurological dysfunction and rates of minor neurological dysfunction at the three ages were not different between the three conception groups. CONCLUSIONS: We found no effects of ovarian hyperstimulation or the in vitro procedure itself on neurological outcome in children aged 4-18 months. The findings of our study are reassuring, nevertheless it should be kept in mind that subtle neurodevelopmental disorders may emerge when children grow older. Continuation of follow-up in older and larger groups of children is therefore still needed.

The predictive value of ovarian reserve tests for miscarriage in a population of subfertile ovulatory women.

BACKGROUND: The increase in miscarriage rate with female age is attributed to a decline in oocyte quality. This age-related decrease of oocyte quality is accompanied by a decrease in oocyte quantity. Assessment of the number of oocytes by ovarian reserve tests (ORTs) may therefore also represent their quality. The objective of our study was to assess the predictive value of ORTs for miscarriage in subfertile women. METHODS: This study was a subanalysis within a prospective cohort study of 474 subfertile ovulatory couples in two hospitals in Groningen, The Netherlands. The ORTs performed were: antral follicle count (AFC), basal and stimulated levels of follicle-stimulating hormone (FSH) and inhibin B, and the clomiphene citrate challenge test (CCCT). Women who achieved an ongoing pregnancy (n = 233) were compared with women experiencing miscarriage (n = 72) on the results of their ORTs and patient characteristics. RESULTS: In univariate analysis, the outcome of the ORTs did not differ between the groups. Logistic regression analysis including patient characteristics such as female age did not reveal an association between the ORT results and miscarriage either. CONCLUSIONS: Neither AFC, basal and stimulated levels of FSH and inhibin B, nor the CCCT have a statistically significant predictive value for miscarriage in subfertile ovulatory women.

The predictive value of ovarian reserve tests for spontaneous pregnancy in subfertile ovulatory women.

BACKGROUND: The predictive value of ovarian reserve tests (ORTs) for spontaneous pregnancy is unclear. Our study aimed to determine whether ORTs have added value to previously identified prognostic factors for spontaneous pregnancy in subfertile ovulatory couples. METHODS: A prospective cohort study was performed on 474 subfertile ovulatory couples in two hospitals in Groningen, The Netherlands. The ORTs performed were: antral follicle count (AFC), follicle-stimulating hormone (FSH), inhibin B (basal levels and after stimulation with clomiphene citrate) and the clomiphene citrate challenge test. For each couple, the probability of spontaneous pregnancy was retrospectively calculated using the validated Hunault prediction model which includes the main known prognostic factors for spontaneous pregnancy. Outcome measure was time to spontaneous pregnancy resulting in a live birth. RESULTS: When added to the Hunault model, only basal FSH and AFC significantly improved the prediction of spontaneous pregnancy (P-values of 0.05 and 0.04). Absolute changes in predicted probabilities after adding basal FSH or AFC were small: the predicted probability of spontaneous pregnancy shifted >or=10% in only 3.8% and 7.9% of the couples, respectively. CONCLUSIONS: Although basal FSH and AFC significantly improved the validated prediction model for spontaneous pregnancy, the clinical relevance of this finding is limited. We recommend that none of the ORTs studied should be used routinely in the subfertility evaluation of ovulatory couples to predict spontaneous pregnancy chances.

Approximal secondary caries lesion progression, a 20-week in situ study.

There is no consensus about the definition and progression of outer and wall lesions in secondary caries. In this study we investigated whether lesion progression is influenced by an adjacent composite restoration and whether wall lesions develop at the composite-tooth interface. In order to study the appearance and progression of approximal primary caries lesions and lesions next to composite restorations, 16 samples were placed in a full denture of each of 8 subjects. Each denture housed 4 restored and 4 unrestored enamel samples and similarly 8 dentin samples. All samples were distributed over 2 sample holders, in each of which 4 approximal spaces were simulated. Every 4 weeks the sample holders were microradiographed using transversal wavelength independent microradiography and lesion depth was measured. At the end of the study, after 20 weeks, the lesion depth of the outer lesions was 0-350 microm for enamel and 0-750 microm for dentin. The estimated difference in progression between secondary and primary lesions (1.1 microm/4 weeks, 95% CI: -9.2 to 11.4 microm) was not statistically significant (p = 0.83). Secondary outer lesions appeared and progressed as primary caries lesions. No clear wall lesions were found next to composite, but they were observed next to acrylic resin.

A comparison of the clinical use of the Laryngeal Tube S and the ProSeal Laryngeal Mask Airway by first-month anaesthesia residents in anaesthetised patients.

The Laryngeal Tube S and the LMA-ProSeal are supraglottic instruments with an improved airway seal and a drainage tube to protect against regurgitation and to facilitate passage of a gastric tube. We compared the feasibility of these two instruments in a randomised, controlled clinical trial. One hundred and sixty patients were randomly allocated to undergo insertion of a Laryngeal Tube S (n = 82) or an LMA-ProSeal (n = 78). All insertions were carried out by first-month anaesthesia residents. Success rates were not significantly different: Laryngeal Tube S 89%, LMA-ProSeal 95%. There was also no significant difference in leak pressure or insertion time. Insertion time decreased significantly when we compared the first with the last 10 insertions. Gastric tube placement was successful in all patients in the Laryngeal Tube S group, but failed in 12 patients in the LMA-ProSeal group (p < 0.001). Dysphagia was reported by 22% of Laryngeal Tube S group and 3% of LMA-ProSeal group (p = 0.001). These findings demonstrate the applicability of the devices and a learning effect in the hands of anaesthesia residents with limited experience.

Effect of fluoridated toothpicks and dental flosses on enamel and dentine and on plaque composition in situ.

The aim was to evaluate the effect of two toothpicks and two dental flosses on demineralized enamel and dentine and on plaque composition, using an in situ model with simulated approximal spaces within dentures. Fifteen subjects with full dentures were recruited and 14 completed the study. It consisted of two crossover periods, the first comparing a birch toothpick with AmF and a birch toothpick with NaF, and the second comparing a dental floss with AmF + NaF and a dental floss without F. Between these four periods, there was a control period without any approximal cleaning. In small, rectangular sample holders, one enamel and one dentine specimen were embedded, forming a triangular, approximal-like space. Two sample holders were mounted in the premolar-molar region of the upper or lower dentures. The subjects used the toothpicks or dental flosses 3 times/day for 4 weeks. The results showed that all toothpicks and dental flosses inhibited further demineralization compared to the control period (p < 0.001). The dental flosses were somewhat more effective in this respect than the toothpicks, especially in dentine. There were relatively small numerical differences between AmF and NaF toothpicks, but in favour of NaF regarding mineral gain (p < 0.05). The fluoridated floss gave somewhat less lesion depth in dentine than the non-fluoridated floss (p < 0.01). Toothpicks and flosses resulted in lower counts of microorganisms in plaque compared to the control period (p < 0.001); the AmF toothpick gave a more pronounced reduction than the NaF toothpick (p < 0.001).

Portal and systemic serum growth factor and acute-phase response after laparotomy or partial hepatectomy in patients with colorectal liver metastases: a prognostic role for C-reactive protein and hepatocyte growth factor.

BACKGROUND: Growth factors play a role in wound healing and tumour growth. The aim of this study was to compare the effect of partial hepatectomy (PH) and laparotomy on serum levels of growth factors and acute-phase proteins in patients with colorectal liver metastases and to correlate these levels with prognosis after PH. METHODS: Epidermal growth factor (EGF), hepatocyte growth factor (HGF), insulin like growth factor-I (IGF-I), insulin, interleukin-6 (IL-6), C-reactive protein (CRP) and serum amyloid-A (SAA) were determined in portal and systemic serum in 24 PH patients and 9 laparotomy patients. RESULTS: No differences were found in the clinicopathological characteristics of PH and laparotomy patients with the exception of the number of metastases, blood loss and operation time. The response of SAA, CRP and IGF-I was lower in PH patients than in laparotomy patients (P < 0.02). PH was associated with a higher IL-6 (P = 0.02) and HGF (P = 0.055) response than laparotomy. A higher HGF and CRP response was associated with a poorer prognosis. Total IGF-I was negatively correlated with the resected liver volume (r = -0.48, P < 0.05). CONCLUSIONS: PH is associated with a lower acute-phase and total IGF-I response and a higher HGF and IL-6 response compared with laparotomy. HGF and CRP responses had an influence on the prognosis.

Early changes of thyroid hormone concentrations after (131)I therapy in Graves' patients pretreated or not with methimazole.

AIM: Despite extensive use of (131)I therapy for Graves' hyperthyroidism the treatment regimen with (131)I and antithyroid drugs remain under discussion. In our prospective clinical study we followed acute thyroid hormone changes after (131)I in patients not pretreated with methimazole (MMI) and in patients with different MMI pretreatment regimens. PATIENTS, METHODS: 187 patients were treated with fixed activity of 550 or 740 MBq of (131)I. First group (71 patients) received (131)I alone. In the second group (57 patients) MMI was stopped seven days before (131)I. The third group (59 patients) received MMI until (131)I application. Initial free triiodothyronin and free thyroxin were measured in the second group 7 and 2 days before (131)I therapy and in all three groups on the day of (131)I application as well as 2, 5, 12, and 30 days afterwards. Absorbed dose was measured in each patient. RESULTS: In the non-pretreated group (131)I application was followed by a significant decrease of fT4 in 5 days and of fT3 in 2 days, higher reduction was detected in patients with higher baseline values. In MMI pretreated patients significant but clinically irrelevant increase of both thyroid hormones was detected with maximum value 7 days after discontinuation in the second group and 5 days after discontinuation in the third group. Additionally, in patients of the third group absorbed dose of (131)I was significantly lower relative to other two groups. We found no correlation between absorbed dose of (131)I and thyroid hormone changes. CONCLUSION: Our study demonstrates that (131)I application alone does not result in exacerbation of hyperthyroidism and therefore it may be considered as safe. Additionally, MMI withdrawal causes significant but clinically irrelevant elevation of thyroid hormones.

Recovery from acute whiplash: the role of coping styles.

STUDY DESIGN: Prospective cohort study. Victims of car accidents who initiated compensation claim procedures at a Dutch insurance company and presented themselves with neck complaints were sent a questionnaire containing neck-related questions and questions regarding the coping styles used shortly after the accident. An additional two questionnaires were administered 6 and 12 months, respectively, after the accident. OBJECTIVES: To examine the association between the coping styles used and the development of late whiplash syndrome. SUMMARY OF BACKGROUND DATA: Previous research has indicated that neither personality traits nor psychopathologic symptoms can predict the outcome of whiplash. No studies have yet been conducted on the association between coping styles and the development of late whiplash syndrome. METHODS: The coping styles were determined using the Utrecht Coping List. The duration of neck complaints was measured from the time of the accident and from the time of filling in the first questionnaire. Survival analysis was used to study the association between the duration of neck complaints and the explanatory variables. RESULTS: Of the 363 eligible claimants, 278 (77%) responded to the questionnaire; 242 (67%) were included in the analysis. After 12 months, 40% of the male and 50% of the female participating claimants still had neck complaints. The duration of the neck complaints was associated with gender, palliative reaction, and the seeking social support coping style. CONCLUSION: The coping style during the first few weeks after the accident and the gender are related to the duration of neck complaints (Cox regression: palliative handling relative risk = 0.91, P = 0.002; seeking social support relative risk = 1.06, P = 0.042; and gender relative risk = 1.50, P = 0.036). Thereafter the intensity of somatic complaints plays a role. Paying attention to the coping style could contribute to the prevention of the development of late whiplash syndrome.

Early change of thyroid hormone concentration after 131I treatment in patients with solitary toxic adenoma.

AIM: In spite of extensive use of 131I for treatment of hyperthyroidism, the results of early outcome are variable. In our prospective clinical study we tested whether 131I induced necrosis causing clinical aggravation of hyperthyroidism and increasing the free thyroid hormone concentration in the serum of patients with solitary toxic adenoma not pretreated with antithyroid drugs. PATIENTS AND METHODS: 30 consecutive patients were treated with 925 MBq 131I. Serum concentration of thyrotropin (TSH), free thyroxine (fT4), free triiodothyronine (fT3), thyroglobulin (Tg), and interleukin-6 (IL-6) were measured before and after application of 131I. RESULTS: After application of 131I no clinical worsening was observed. FT4 and fT3 concentration did not change significantly within the first five days, whereas both of them significantly decreased after 12 days (p < 0.0001). Slight and clinically irrelevant increase in the level of the two thyroid hormones was observed in 9 patients. Furthermore, we observed a prolonged increase in Tg concentration and a transient increase in IL-6 concentration. CONCLUSION: Neither evidence of any clinical aggravation of hyperthyroidism nor any significant increase in thyroid hormone concentration by 131I induced necrosis of thyroid cells was found. Therefore, the application of 131I may be considered as a safe and effective treatment for patients with hyperthyroidism due to toxic adenoma.

Spherical and irregular aberrations are important for the optimal performance of the human eye.

Contrast sensitivity measured psychophysically at different levels of defocus can be used to evaluate the eye optics. Possible parameters of spherical and irregular aberrations, e.g. relative modulation transfer (RMT), myopic shift, and depth of focus, can be determined from these measurements. The present paper compares measured results of RMT, myopic shift, and depth of focus with the theoretical results found in the two eye models described by Jansonius and Kooijman (1998). The RMT data in the present study agree with those found in other studies, e.g. Campbell and Green (1965) and Jansonius and Kooijman (1997). A new theoretical eye model using a spherical aberration intermediate between those of the eye models described by Jansonius and Kooijman (1998) and an irregular aberration with a typical S.D. of 0.3-0.5 D could adequately explain the measured RMT, myopic shift, and depth of focus data. Both spherical and irregular aberrations increased the depth of focus, but decreased the modulation transfer (MT) at high spatial frequencies at optimum focus. These aberrations, therefore, play an important role in the balance between acuity and depth of focus.

[Intensive patient education and treatment program for young adults with atopic eczema]. / Intensives Patientenschulungs- und Behandlungsprogramm für junge Erwachsene mit atopischem Ekzem.

BACKGROUND AND OBJECTIVE: By means of a 2-week intensive multidisciplinary training & treatment course in small groups (ISBP), young adults with atopic dermatitis may be able to achieve better self-management of their disease and reduce their number of doctor visits. METHODS: Patients aged 18-35 with moderate to severe atopic dermatitis (SCORAD > 20) were randomized in a treatment (ISBP) group of n = 31 and a control group of n = 20. Follow-up was 9 months. The outcome was assessed using validated primary and secondary parameters, both specific for atopic dermatitis and more general. RESULTS: Participants in the ISBP scored significantly better at follow-up in the Marburger atopic dermatitis-specific questionnaire and the self-care parameter, needed less time for medical consultations, and used more emollients without corticosteroids. Absence from work/sick leave was less at 10 weeks follow-up, but equal at 9 months. CONCLUSIONS: The ISBP program can be judged successful because both the patients and their doctors perceive their interactions as more efficient, less time time-consuming and more satisfying.

Serum response of hepatocyte growth factor, insulin-like growth factor-I, interleukin-6, and acute phase proteins in patients with colorectal liver metastases treated with partial hepatectomy or cryosurgery.

BACKGROUND/AIMS: The aim of the study was to compare the serum response of regeneration factors and acute phase proteins in patients treated with partial hepatectomy or cryosurgery. METHODS: The responses of serum hepatocyte growth factor (HGF), insulin-like growth factor-I (IGF-I) (free and total), interleukin-6 (IL-6) and the acute phase proteins, C-reactive protein (CRP) and serum amyloid A (SAA) were examined in patients with colorectal liver metastases treated with partial hepatectomy (n = 14) or cryosurgery (n = 10). RESULTS: In both groups, IL-6 peak levels at the end of the operation were followed by peak levels at day 1 for HGF and CRP. SAA peak levels occurred on day 1 (hepatectomy group) and on day 4 (cryo group). The total HGF, IGF-I, and IL-6 responses were comparable in both groups. CRP and SAA responses were higher in the patients treated with cryosurgery than in patients after hepatectomy. Free IGF-I trough levels were lower in partial hepatectomy patients than in cryosurgery patients. CONCLUSIONS: In patients with colorectal liver metastases the responses of the regenerating factors HGF, IGF-I, and IL-6 are comparable to those in patients treated with partial hepatectomy. Upregulation of acute phase protein production is higher in patients after cryosurgery than in patients after partial hepatectomy.

Age-related changes of defocus-specific contrast sensitivity in healthy subjects.

To investigate the effect of defocus on contrast sensitivity as a function of age in healthy subjects, the through focus contrast sensitivity was measured in 100 healthy subjects aged 20-69. Defocus-specific changes in contrast sensitivity reflect age-related changes in the optics of the eye. Tests were performed in cycloplegic eyes varying artificial pupil size (2, 4 and 6 mm), defocus (-1 to +2 D), and spatial frequency (1-16 cpd). Integrated contrast sensitivity was taken as a measure for the total amount of visual information transferred by the optical media. At optimal focus, integrated contrast sensitivity and log contrast sensitivity at 8 cpd showed a significant age-related decline. The log contrast sensitivity at 1 cpd appeared to be independent of age. The depth of focus for a 4-mm pupil increased significantly with age, even though contrast sensitivity at +2 D defocus decreases with age too, but not as much as the contrast sensitivity at optimal focus. Our study indicates that the effect of defocus on contrast sensitivity decreases with age; this was attributed to age-related changes in the optical media.

Preoperative staging of non-small-cell lung cancer with positron-emission tomography.

BACKGROUND: Determining the stage of non-small-cell lung cancer often requires multiple preoperative tests and invasive procedures. Whole-body positron-emission tomography (PET) may simplify and improve the evaluation of patients with this tumor. METHODS: We prospectively compared the ability of a standard approach to staging (computed tomography [CT], ultrasonography, bone scanning, and, when indicated, needle biopsies) and one involving PET to detect metastases in mediastinal lymph nodes and at distant sites in 102 patients with resectable non-small-cell lung cancer. The presence of mediastinal metastatic disease was confirmed histopathologically. Distant metastases that were detected by PET were further evaluated by standard imaging tests and biopsies. Patients were followed postoperatively for six months by standard methods to detect occult metastases. Logistic-regression analysis was used to evaluate the ability of PET and CT to identify malignant mediastinal lymph nodes. RESULTS: The sensitivity and specificity of PET for the detection of mediastinal metastases were 91 percent (95 percent confidence interval, 81 to 100 percent) and 86 percent (95 percent confidence interval, 78 to 94 percent), respectively. The corresponding values for CT were 75 percent (95 percent confidence interval, 60 to 90 percent) and 66 percent (95 percent confidence interval, 55 to 77 percent). When the results of PET and CT were adjusted for each other, only PET results were positively correlated with the histopathological findings in mediastinal lymph nodes (P<0.001). PET identified distant metastases that had not been found by standard methods in 11 of 102 patients. The sensitivity and specificity of PET for the detection of both mediastinal and distant metastatic disease were 95 percent (95 percent confidence interval, 88 to 100 percent) and 83 percent (95 percent confidence interval, 74 to 92 percent), respectively. The use of PET to identify the stage of the disease resulted in a different stage from the one determined by standard methods in 62 patients: the stage was lowered in 20 and raised in 42. CONCLUSIONS: PET improves the rate of detection of local and distant metastases in patients with non-small-cell lung cancer.

Estimating treatment effects in randomized clinical trials in the presence of non-compliance.

In clinical trials where patients are randomized between two treatment arms, not all patients comply with the treatment they were randomly assigned to. The reasons for (non)compliance may be associated with the outcome variable and thereby act as confounders. The standard way of analysing such trials is by the 'intention-to-treat' principle, which allows the use of permutation tests. Conclusions drawn from such tests do not depend on untested assumptions such as absence of confounding. However, this approach may yield biased estimators for the causal effects of treatments. We consider the estimation of such effects for clinical trials where non-compliers can be considered to have switched to the other trial arm. The most important example of this is the placebo-controlled clinical trial where no substantial placebo effects are anticipated. We consider the situation where the relationship between compliance, and thus treatment received, and outcome is influenced by unobserved confounders. The residual of the regression of the actual treatment indicator variable on the randomization arm indicator variable is shown to 'intercept' the effect of such confounders. Inclusion of this residual in a multivariate analysis, in conjunction with the treatment indicator variable, should thus adjust for confounding. Examples are given. In those examples, the results are similar to those obtained by more complex methods.

Quantification of the diastolic notch in Doppler ultrasound screening of uterine arteries.

OBJECTIVE: To investigate a new method of quantification of the diastolic notch of the flow velocity waveforms of uterine arteries in the prediction of hypertensive disorders of pregnancy. METHODS: Pulsed-wave Doppler was used to obtain flow velocity waveforms (FVWs) from the uterine arteries at 21-22 weeks of gestation from 531 nulliparous women and 94 multiparous women at high risk. From the FVWs, both the pulsatility index (PI) and the notch index (NI) were calculated and the predictive values for both indices were compared using logistic regression analysis for mild and severe early onset hypertensive pregnancy complications. RESULTS: Both the PI and the NI were poor predictors for mild gestational hypertension and pre-eclampsia; predictive values for severe early onset disease, however, were much better. Logistic regression analysis showed the NI has no additional value compared with the PI in the prediction of either mild or severe disease. CONCLUSIONS: The NI offers the possibility to quantify the diastolic notch in uterine artery analysis. Compared to the PI, this does not lead to better predictive values for hypertensive disorders of pregnancy.

The effect of single twitch and train-of-four stimulation on twitch forces during stable neuromuscular block.

OBJECTIVE: We investigated whether the response to a single twitch (ST) stimulus or the first response (T1) to a train-of-four (TOF; 4 stimuli at 2 Hz) stimulus following a stimulus interval of 10 s (i.e., the time between two consecutive ST or TOF stimuli) is influenced by the preceding stimulus in the presence of a stable 50% neuromuscular block. In addition, we determined whether ST and TOF stimulation yield different results under these circumstances. METHODS: Twitch forces were measured in both tibialis anterior muscles of six cats. In the presence of a stable 50% neuromuscular block the stimulation pattern (ST or TOF) or stimulus interval (3.3, 10 or 30 s) was varied every 30 min. A linear mixed model was used for statistical analysis. RESULTS: ST forces with a stimulus interval of 3.3 s were 10.3% (95% CI: 7.3-13.3%) smaller than those with a stimulus interval of 10 s. For T1 forces this effect was 15.2% (95% CI: 12-18.4%). There was no significant difference between twitch forces with stimulus intervals of 30 and 10 s. For a stimulus interval of 3.3 s the ST forces exceeded the T1 forces by 7.6% (95% CI: 4.4-10.8%); no significant differences were found between the ST and T1 forces for stimulus intervals of 10 and 30 s. CONCLUSIONS: The ST or T1 force during stimulation with a stimulus interval of 10 s or more during a stable 50% neuromuscular block in the tibialis anterior muscle of the cat is not affected by the preceding stimulus. In addition, ST and T1 forces do not differ when employing a stimulus interval of 10 s or more under these circumstances. Our results thus indicate that the known differences between ST and T1 forces after a bolus injection of a muscle relaxant can not be explained by differences in acetylcholine release when the stimulus interval exceeds 10 s.

Plasma IL-8 and IL-6 levels can be used to define a group with low risk of septicaemia among cancer patients with fever and neutropenia.

The standard therapy for patients with fever and chemotherapy-related neutropenia is hospitalization and infusion of broad-spectrum antibiotics. Early discharge of a defined group of patients at low risk for septicaemia would be of great advantage for these patients. In this study plasma interleukin-8 (IL-8) and interleukin-6 (IL-6) levels measured at start of fever (n = 72) could define a low-risk group of febrile patients with neutropenia due to chemotherapy. For this purpose we collected and analysed data on 72 fever episodes from 53 patients with chemotherapy-related neutropenia, aged between 1 and 66 years. Of the 72 episodes, 18 were classified as bacteraemia and/or clinical sepsis (sepsis group). The IL-6 and IL-8 plasma concentration were significantly increased in patients with chemotherapy-related neutropenia and fever due to bacteraemia versus fever of non-bacterial origin (P = 0.043 and P = 0.022 respectively). Logistic regression analysis, with sepsis as the outcome variable, revealed significant effects of age combined with either IL-6 or IL-8. Sepsis occurrence was lowest for patients <16 years and highest in patients between 16 and 50 years, and was higher in patients with increased IL-6 (P = 0.032) or IL-8 (P = 0.049). No significant effect of leucocyte count, C-reactive protein, sex or underlying malignancy at presentation was detected. The plasma IL-6 and IL-8 levels were fairly strongly correlated (Pearson r = 0.62). Using a cut-off value with 100% sensitivity, both IL-8 and IL-6 could define a low-risk group of neutropenic patients of 28% (CI 15-40%) at the start of the febrile period. Intervention studies are warranted to confirm this result and to investigate whether an early discharge based on IL-8 or IL-6 measurement is safe, increases the quality of life, and results in cost savings.