Pre-hospital transfusion of red blood cells in civilian trauma patients.

INTRODUCTION: The current management of severely injured patients includes damage control resuscitation strategies that minimise the use of crystalloids and emphasise earlier transfusion of red blood cells (RBC) to prevent coagulopathy. In 2012, London's air ambulance (LAA) became the first UK civilian pre-hospital service to routinely carry RBC to the trauma scene. OBJECTIVE: To investigate the effect of pre-hospital RBC transfusion (phRTx) on overall blood product consumption. METHODS: A retrospective trauma database study compares before implementation with after implementation of phRTx in exsanguinating trauma patients transported directly to one major trauma centre. Pre-hospital deaths were excluded. Univariate and multivariate Poisson regression analyses on data subject to multiple imputation were conducted. RESULTS: We included 137 and 128 patients in the before and after the implementation of phRTx groups, respectively. LAA transfused 304 RBC units (median 2, inter quartile range 1-3). We found a significant reduction in total RBC usage and reduced early use of platelets and fresh-frozen plasma (FFP) after the implementation of phRTx in both univariate (P < 0·001) and multivariate analyses (P < 0·001). No immediate adverse transfusion reactions were identified. CONCLUSION: Pre-hospital trauma transfusion practice is feasible and associated with overall reduced RBC, platelets and FFP consumption.

The success of pre-hospital tracheal intubation by different pre-hospital providers: a systematic literature review and meta-analysis.

BACKGROUND: Pre-hospital basic airway interventions can be ineffective at providing adequate oxygenation and ventilation in some severely ill or injured patients, and advanced airway interventions are then required. Controversy exists regarding the level of provider required to perform successful pre-hospital intubation. A previous meta-analysis reported pre-hospital intubation success rates of 0.849 for non-physicians versus 0.991 for physicians. The evidence base on the topic has expanded significantly in the last 10 years. This study systematically reviewed recent literature and presents comprehensive data on intubation success rates. METHODS: A systematic search of MEDLINE and EMBASE was performed using PRISMA methodology to identify articles on pre-hospital tracheal intubation published between 2006 and 2016. Overall success rates were estimated using random effects meta-analysis. The relationship between intubation success rate and provider type was assessed in weighted linear regression analysis. RESULTS: Of the 1838 identified studies, 38 met the study inclusion criteria. Intubation was performed by non-physicians in half of the studies and by physicians in the other half. The crude median (range) reported overall success rate was 0.969 (0.616-1.000). In random effects meta-analysis, the estimated overall intubation success rate was 0.953 (0.938-0.965). The crude median (range) reported intubation success rates for non-physicians were 0.917 (0.616-1.000) and, for physicians, were 0.988 (0.781-1.000) (p = 0.003). DISCUSSION: The reported overall success rate of pre-hospital intubation has improved, yet there is still a significant difference between non-physician and physician providers. The finding that less-experienced personnel perform less well is not unexpected, but since there is considerable evidence that poorly performed intubation carries a significant risk of morbidity and mortality careful consideration should be given to the training and experience required to deliver this intervention safely.

Safety of the lateral trauma position in cervical spine injuries: a cadaver model study.

BACKGROUND: Endotracheal intubation is not always an option for unconscious trauma patients. Prehospital personnel are then faced with the dilemma of maintaining an adequate airway without risking deleterious movement of a potentially unstable cervical spine. To address these two concerns various alternatives to the classical recovery position have been developed. This study aims to determine the amount of motion induced by the recovery position, two versions of the HAINES (High Arm IN Endangered Spine) position, and the novel lateral trauma position (LTP). METHOD: We surgically created global cervical instability between the C5 and C6 vertebrae in five fresh cadavers. We measured the rotational and translational (linear) range of motion during the different maneuvers using an electromagnetic tracking device and compared the results using a general linear mixed model (GLMM) for regression. RESULTS: In the recovery position, the range of motion for lateral bending was 11.9°. While both HAINES positions caused a similar range of motion, the motion caused by the LTP was 2.6° less (P = 0.037). The linear axial range of motion in the recovery position was 13.0 mm. In comparison, the HAINES 1 and 2 positions showed significantly less motion (-5.8 and -4.6 mm, respectively), while the LTP did not (-4.0 mm, P = 0.067). CONCLUSION: Our results indicate that in unconscious trauma patients, the LTP or one of the two HAINES techniques is preferable to the standard recovery position in cases of an unstable cervical spine injury.

Assessment of acute stroke cerebral CT examinations by anaesthesiologists.

BACKGROUND AND PURPOSE: It is essential to diagnose ischaemic stroke as soon as possible after symptom onset, so that thrombolytic treatment can be initiated as quickly as possible. This might be greatly facilitated if cerebral CT could be carried out in a pre-hospital setting. The aim of this study was to evaluate if anaesthesiologists, who in Norway provide pre-hospital medical care, could be trained to assess cerebral CT scans to exclude radiological contraindications for thrombolytic stroke treatment. METHODS: Thirteen anaesthesiologists attended an 8-h course in acute stroke assessment, including a 2-h introduction to the neuroradiology of acute stroke. Each participant then assessed 12 non-contrast cerebral CT examinations of acute stroke patients with specific regard to radiological contraindications for thrombolytic therapy. Test results were compared with those of three experienced neuroradiologists. Inter-rater agreement between anaesthesiologists and neuroradiologists was calculated using Cohen's Kappa statistics. Robustness of the results was assessed using the non-parametric bootstrap. RESULTS: Among the neuroradiologists, Kappa was 1 for detecting radiological contraindications for thrombolytic therapy. Twelve of the 13 anaesthesiologists showed good or excellent agreement (Kappa > 0.60) with the neuroradiologists. The anaesthesiologists spent a median time of 2 min and 18 s on each CT scan. CONCLUSIONS: This study suggests that anaesthesiologists who are experienced in pre-hospital care may be quickly trained to assess cerebral CT examinations in acute stroke patients with regard to radiological contraindications for thrombolytic therapy.

Validation of a portable monitor for the diagnosis of obstructive sleep apnea in morbidly obese patients.

STUDY OBJECTIVES: We aimed to validate the diagnostic accuracy and night-to-night variability of a simple 3-channel (type IV monitor) portable sleep monitor, ApneaLink (AL), in a population of morbidly obese subjects. DESIGN: Cross-sectional validation and diagnostic accuracy study. SETTING: Public tertiary care obesity center in Norway. PARTICIPANTS: A total of 105 (67 females) treatment seeking morbidly obese subjects were included, mean (SD) age 44.3 (11.4) years and BMI 43.6 (5.6) kg/m2. INTERVENTIONS: The patients underwent two successive nights of recordings; the first night with the AL only, and the following night with both the reference instrument Embletta (E), a type III portable somnograph, and the AL. MEASUREMENTS AND RESULTS: Main outcomes were diagnostic accuracy of AL as assessed by sensitivity, specificity and area under ROC curves, and level of agreement between AL and E. AL had high diagnostic accuracy at all levels of OSA, and the Bland-Altman plots showed good agreement between AL and E. The sensitivity and specificity of the instrument were 93% and 71% at the AHI cutoff 5 events/h, and 94% and 94% at the AHI cutoff 15, respectively. The night-to-night variability was low. CONCLUSION: Our results indicate that a simple 3-channel portable sleep monitor (ApneaLink) has a high diagnostic accuracy in diagnosing OSA in morbidly obese treatment seeking patients. Accordingly, this and similar instruments might help non-specialists to diagnose OSA in morbidly obese patients, and, importantly, help non-specialists to refer patients who need specific treatment to specialist without unnecessary delay.

Physiologic, demographic and mechanistic factors predicting New Injury Severity Score (NISS) in motor vehicle accident victims.

BACKGROUND: Current literature on motor vehicle accidents (MVAs) has few reports regarding field factors that predict the degree of injury. Also, studies of mechanistic factors rarely consider concurrent predictive effects of on-scene patient physiology. The New Injury Severity Score (NISS) has previously been found to correlate with mortality, need for ICU admission, length of hospital stay, and functional recovery after trauma. To potentially increase future precision of trauma triage, we assessed how the NISS is associated with physiologic, demographic and mechanistic variables from the accident site. METHODS: Using mixed-model linear regression analyses, we explored the association between NISS and pre-hospital Glasgow Coma Scale (GCS) score, Revised Trauma Score (RTS) categories of respiratory rate (RR) and systolic blood pressure (SBP), gender, age, subject position in the vehicle, seatbelt use, airbag deployment, and the estimated squared change in vehicle velocity on impact ((Δv)(2)). Missing values were handled with multiple imputation. RESULTS: We included 190 accidents with 353 dead or injured subjects (mean NISS 17, median NISS 8, IQR 1-27). For the 307 subjects in front-impact MVAs, the mean increase in NISS was -2.58 per GCS point, -2.52 per RR category level, -2.77 per SBP category level, -1.08 for male gender, 0.18 per year of age, 4.98 for driver vs. rear passengers, 4.83 for no seatbelt use, 13.52 for indeterminable seatbelt use, 5.07 for no airbag deployment, and 0.0003 per (km/h)(2) velocity change (all p<0.002). CONCLUSION: This study in victims of MVAs demonstrated that injury severity (NISS) was concurrently and independently predicted by poor pre-hospital physiologic status, increasing age and female gender, and several mechanistic measures of localised and generalised trauma energy. Our findings underscore the need for precise information from the site of trauma, to reduce undertriage, target diagnostic efforts, and anticipate need for high-level care and rehabilitative resources.

Arterial stiffness, lifestyle intervention and a low-calorie diet in morbidly obese patients-a nonrandomized clinical trial.

OBJECTIVE: Arterial stiffness is an independent predictor of cardiovascular morbidity and mortality. This study aimed to compare the 7-week effect of a low-calorie diet (LCD) and an intensive lifestyle intervention program (ILI) on arterial stiffness in morbidly obese individuals. DESIGN AND METHODS: Nonrandomized clinical trial. The LCD provided 900 kcal/day, and participants in the LCD group were instructed to maintain their habitual physical activity level. The ILI included two 90-min supervised training sessions 3 days a week at moderate to high intensity (4-8 METs) and a caloric restriction of 1000 kcal/day. RESULTS: A total of 179 individuals completed the study, 88 (56 women) in the ILI group and 91 (57 women) in the LCD group. High-fidelity applanation tonometry (Millar(®) , Sphygmocor(®) ) was used to measure carotid-femoral pulse wave velocity (PWV). After adjustment for relevant confounders, the ILI group had a significantly greater reduction in PWV than the LCD group; -0.4 (-0.6, -0.1) m/s, P = 0.004. When compared to the LCD group, the ILI group showed a larger reduction in systolic and diastolic blood pressure -5 (-9, -1) and -5 (-7, -2) mmHg, P = 0.038 and P ≤ 0.001 respectively, whereas no difference was observed regarding pulse pressure, P = 0.661. No significant differences between groups were found regarding the loss of fat mass, P = 0.259, but the loss of muscle mass was larger in the LCD group, 0.8 (0.5, 1.1) kg, P ≤ 0.001. CONCLUSION: Despite the limitations of a nonrandomized design, our findings indicate that for morbidly obese individuals a moderate caloric restriction combined with aerobic physical exercise is associated with a greater decline in PWV than a LCD alone.

The effectiveness of secondary and tertiary care lifestyle intervention in morbidly obese patients: a 1-year non-randomized controlled pragmatic clinical trial.

In this non-randomized clinical pragmatic trial, we aimed to compare the effectiveness of an outpatient intensive lifestyle intervention (ILI) programme conducted in a tertiary care obesity rehabilitation centre with an outpatient moderate lifestyle intervention (MLI) programme at a secondary care obesity centre. Effectiveness was measured in terms of the 1-year effect each programme had on body weight, physical activity and health-related quality of life (HRQL). A total of 232 morbidly obese subjects were recruited to the ILI group and 140 to the MLI group, with retention rates of 78% and 44%, respectively. The ILI group had a significantly larger mean (95% confidence interval [CI]) weight loss than the MLI group, 11% (9%, 12%) vs. 2% (1%, 6%), P < 0.001, and a larger proportion of completers attaining ≥5% weight loss (71% vs. 33%), P < 0.001. Compared with the MLI group, the ILI group achieved a significant larger mean (95% CI) increase in the physical dimension of HRQL 6.9 (4.4, 9.3), P < 0.001, the mental dimension of HRQL 4.4 (1.4, 7.4), P = 0.018 and in the emotional dimension of HRQL 17.8 (12.8, 22.6), P < 0.001. There were no significant differences in terms of changes in physical activity. Compared with MLI, ILI was associated with significantly larger weight loss and better HRQL.

Pulmonary function and blood gases after gastric bypass and lifestyle intervention: a comparative study.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Impaired lung function associated with obesity improves with weight loss. WHAT THIS STUDY ADDS: This is the first study to compare the effects of obesity surgery and intensive lifestyle intervention on pulmonary function and arterial blood gases. Arterial oxygenation and pulmonary function improved to a greater extent after gastric bypass than after lifestyle intervention. The superiority of surgical treatment might be mediated by greater weight loss after gastric bypass. Impaired lung function associated with obesity improves with weight loss. The effects of obesity surgery and intensive lifestyle intervention on pulmonary function and arterial blood gases have not previously been subjected to comparative examination. In this 1-year non-randomized controlled clinical trial (ClinicalTrials.gov identifier NCT00273104), 139 morbidly obese subjects (19-66 years, mean [standard deviation] body mass index [BMI] 45.1 kg m(-2) [5.6], 107 women) were treated with either Roux-en-Y gastric bypass surgery (n = 76) or intensive lifestyle intervention (n = 63). Mean weight reduction was 30 (8)% and 8 (9)%, respectively. Dynamic and static lung volumes, gas diffusing capacity and arterial blood gases were measured. Compared with lifestyle intervention, surgery resulted in a significantly greater increase in forced vital capacity (mean [95% confidence interval] between-group difference, 7 [4-10]%), forced expiratory volume in 1 s (7 [5-9]%), total lung capacity (5 [1-8]%), vital capacity (7 [4-9]%), functional residual capacity (18 [12-24]%), expiratory reserve volume (48 [30-66]%) and partial pressure of oxygen in arterial blood (0.5 [0.0-1.0] kPa). These associations either disappeared or diminished after adjusting for weight loss. Reduced central adiposity (waist circumference and waist-to-hip ratio) and systemic inflammation (C-reactive protein and adiponectin) had no effect on pulmonary function beyond the effect of reduced general adiposity (BMI). In morbidly obese subjects, gastric bypass surgery is more effective than lifestyle intervention at improving arterial oxygenation and pulmonary function. The effect might be mediated by greater weight loss after surgical treatment.

Evaluating the properties of the coefficient of multiple correlation (CMC) for kinematic gait data.

When assessing reliability of three dimensional gait analysis, the coefficient of multiple correlation (CMC), a measure of similarity of waveforms, is frequently used. Several shortcomings of the method have been reported. It is strongly related to the range of motion (ROM); it is supposed to take values from 0 to 1, but is known to obtain complex values and break down. Removing offset before calculations appears to make it insensitive to apparent differences in gait. In the present work we use stochastic simulations to demonstrate why all of this happens, and the consequences thereof. We also demonstrate other, lesser-known, issues with the method, such as the strong dependency on number of subjects and test situations. The results are demonstrated on real data from an inter-rater repeatability study. We conclude that the CMC in its current form is generally unsuitable as a tool for assessing reliability in kinematic gait data.

Functional limits of agreement: a method for assessing agreement between measurements of gait curves.

Three dimensional measurements of gait is a widely used tool in clinical gait analysis, and the evaluation of the reliability and reproducibility of the method is a recurring topic in the literature. The reliability of gait curve measurements is often assessed by extraction of single points from the gait curves before applying traditional reliability measures for scalars. This approach does, however, not explore the entire gait curves as continuous functions of time. In order to assess agreement between gait curves measured by different measurement methods, or measurers, we propose an extension of the concept of limits of agreement (LoA) to curve data. The LoA represent the estimated variation in the actual observations, which are then to be accompanied by an evaluation of whether this observed variation is within clinically acceptable limits. The generalization of the methodology from scalars to continuous function, e.g. gait curves, can be done using functional data analysis (FDA), a statistical methodology particularly developed for analyzing functional data. The resulting functional limits of agreement (FLoA) are continuous functions from 0 to 100% of the gait cycle, representing the difference in gait curves as measured by different measurement methods. The FLoA are presented in actual degrees for each joint and plane under study. The proposed methodology is demonstrated on real data from an inter-rater repeatability study.

Impact of gender on vitamin D deficiency in morbidly obese patients: a cross-sectional study.

BACKGROUND/OBJECTIVE: Obesity is associated with vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) <50 nmol/l). We aimed to examine the effect of gender on vitamin D status in severe obesity. SUBJECTS/METHODS: Cross-sectional study of 2026 morbidly obese patients examined consecutively at a tertiary care centre between November 2005 and June 2010. Serum 25(OH)D concentration and use of vitamin D supplements were registered in all patients. Total vitamin D intake (µg/day) was assessed in a subgroup of 154 patients using a validated food frequency questionnaire. RESULTS: The male (n=690) and female (n=1336) patients had a mean (s.d.) age of 45.0 (12.1) years and 42.2 (12.2) years (P<0.001), body mass index (BMI) of 44.6 (6.0) kg/m(2) and 44.3 (5.9) kg/m(2) (P=0.30) and waist circumference (WC) of 140 (13) cm and 127 (13) cm (P<0.001), respectively. Male patients had significantly lower mean 25(OH)D concentrations than female patients 50.0 (22.0) nmol/l versus 53.6 (22.4) nmol/l (P=0.001) and a higher rate of vitamin D deficiency (56% versus 47%; P<0.001). Obese men had significantly higher odds of vitamin D deficiency than women (odds ratio=1.41; 95% confidence interval: 1.17-1.70, P<0.001), also after adjustment for season, age, current smoking, intake of vitamin D supplements, BMI and WC (odds ratio=1.39; 95% confidence interval: 1.10-1.76). CONCLUSIONS: Morbidly obese Norwegian men seeking weight loss treatment have significantly higher odds of vitamin D deficiency than women. Monitoring of 25(OH)D concentrations in obese patients should therefore take gender into account.

Correction of an unexpected increasing trend in glucose measurements during 7 years recruitment to a cohort study.

OBJECTIVES: To study an unexpected, significant increase in glucose measurements during 7 year recruitment to a cohort study. DESIGN AND METHODS: Measurements of quality control solutions and blood glucose in pregnant women were done by Accu-Chek Sensor glucometer. Time-trends were analysed by regression models and control charts. RESULTS: Cohort measurements were de-trended by weighted linear regressions based on independent control values. CONCLUSIONS: Biologically implausible trends in data can be corrected by using independent control values.

The association of early post-transplant glucose levels with long-term mortality.

AIMS/OBJECTIVE: We aimed to assess the long-term effects of post-transplant glycaemia on long-term survival after renal transplantation. METHODS: Study participants were 1,410 consecutive transplant recipients without known diabetes who underwent an OGTT 10 weeks post-transplant and were observed for a median of 6.7 years (range 0.3-13.8 years). The HRs adjusted for age, sex, traditional risk factors and transplant-related risk factors were estimated. RESULTS: Each 1 mmol/l increase in fasting plasma glucose (fPG) or 2 h plasma glucose (2hPG) was associated with 11% (95% CI -1%, 24%) and 5% (1%, 9%) increments in all-cause mortality risk and 19% (1%, 39%) and 6% (1%, 12%) increments in cardiovascular (CV) mortality risk, respectively. Including both fPG and 2hPG in the multi-adjusted model the HR for 2hPG remained unchanged, while the HR for fPG was attenuated (1.05 [1.00, 1.11] and 0.97 [0.84, 1.14]). Compared with recipients with normal glucose tolerance, patients with post-transplant diabetes mellitus had higher all-cause and CV mortality (1.54 [1.09, 2.17] and 1.80 [1.10, 2.96]), while patients with impaired glucose tolerance (IGT) had higher all-cause, but not CV mortality (1.39 [1.01, 1.91] and 1.04 [0.62, 1.74]). Conversely, impaired fasting glucose was not associated with increased all-cause or CV mortality (0.79 [0.52, 1.23] and 0.76 [0.39, 1.49]). Post-challenge hyperglycaemia predicted death from any cause and infectious disease in the multivariable analyses (1.49 [1.15, 1.95] and 1.91 [1.09, 3.33]). CONCLUSIONS/INTERPRETATION: For predicting all-cause and CV mortality, 2hPG is superior to fPG after renal transplantation. Also, early post-transplant diabetes, IGT and post-challenge hyperglycaemia were significant predictors of death. Future studies should determine whether an OGTT helps identify renal transplant recipients at increased risk of premature death.

The relationship between various measures of obesity and arterial stiffness in morbidly obese patients.

BACKGROUND: Obesity is associated with increased risk of cardiovascular disease. Arterial stiffness assessed by carotid femoral pulse wave velocity (PWV) is an independent predictor of cardiovascular morbidity and mortality. We aimed to investigate how various measures of body composition affect arterial stiffness. METHODS: This is an analysis of cross-sectional baseline data from a controlled clinical trial addressing changes in arterial stiffness after either surgery or lifestyle intervention in a population of morbidly obese patients. High-fidelity applanation tonometry (Millar, Sphygmocor) was used to measure pulse wave velocity (PWV). Carotid femoral PWV is a direct measure of arterial stiffness and is considered to be the gold standard method. The Inbody 720 Body Composition Analyzer was used for bioelectrical impedance analysis (BIA). Spearman's correlation, independent samples t-test, chi-square tests, Fisher's exact test and multiple linear regression analyses were used as statistical methods. RESULTS: A total of 133 patients (79 women), with a mean (SD) age of 43 (11) years were included in the study. Men had a significantly higher prevalence of obesity related comorbidities and significantly higher PWV, 9.1 (2.0) m/s vs. 8.1 (1.8) m/s, p = 0.003, than women. In the female group, PWV was positively correlated with WC, WHtR, BMI and visceral fat area. In the male group, PWV was negatively correlated with BMI. Multiple linear regression analysis showed that increasing BMI, WC, WHtR, visceral fat area and fat mass were independently associated with higher PWV in women, but not in men, after adjustment for age, hypertension and type 2 diabetes. CONCLUSION: Most measures of general and abdominal obesity were predictors of arterial stiffness in female morbidly obese patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT00626964.

Beta cell function after weight loss: a clinical trial comparing gastric bypass surgery and intensive lifestyle intervention.

OBJECTIVE: The effects of various weight loss strategies on pancreatic beta cell function remain unclear. We aimed to compare the effect of intensive lifestyle intervention (ILI) and Roux-en-Y gastric bypass surgery (RYGB) on beta cell function. DESIGN: One year controlled clinical trial (ClinicalTrials.gov identifier NCT00273104). METHODS: One hundred and nineteen morbidly obese participants without known diabetes from the MOBIL study (mean (s.d.) age 43.6 (10.8) years, body mass index (BMI) 45.5 (5.6) kg/m², 84 women) were allocated to RYGB (n = 64) or ILI (n = 55). The patients underwent repeated oral glucose tolerance tests (OGTTs) and were categorised as having either normal (NGT) or abnormal glucose tolerance (AGT). Twenty-nine normal-weight subjects with NGT (age 42.6 (8.7) years, BMI 22.6 (1.5) kg/m², 19 women) served as controls. OGTT-based indices of beta cell function were calculated. RESULTS: One year weight reduction was 30% (8) after RYGB and 9% (10) after ILI (P < 0.001). Disposition index (DI) increased in all treatment groups (all P<0.05), although more in the surgery groups (both P < 0.001). Stimulated proinsulin-to-insulin (PI/I) ratio decreased in both surgery groups (both P < 0.001), but to a greater extent in the surgery group with AGT at baseline (P < 0.001). Post surgery, patients with NGT at baseline had higher DI and lower stimulated PI/I ratio than controls (both P < 0.027). CONCLUSIONS: Gastric bypass surgery improved beta cell function to a significantly greater extent than ILI. Supra-physiological insulin secretion and proinsulin processing may indicate excessive beta cell function after gastric bypass surgery.

Obesity-related cardiovascular risk factors after weight loss: a clinical trial comparing gastric bypass surgery and intensive lifestyle intervention.

OBJECTIVE: Weight reduction improves several obesity-related health conditions. We aimed to compare the effect of bariatric surgery and comprehensive lifestyle intervention on type 2 diabetes and obesity-related cardiovascular risk factors. DESIGN: One-year controlled clinical trial (ClinicalTrials.gov identifier NCT00273104). METHODS: Morbidly obese subjects (19-66 years, mean (s.d.) body mass index 45.1 kg/m(2) (5.6), 103 women) were treated with either Roux-en-Y gastric bypass surgery (n=80) or intensive lifestyle intervention at a rehabilitation centre (n=66). The dropout rate within both groups was 5%. RESULTS: Among the 76 completers in the surgery group and the 63 completers in the lifestyle group, mean (s.d.) 1-year weight loss was 30% (8) and 8% (9) respectively. Beneficial effects on glucose metabolism, blood pressure, lipids and low-grade inflammation were observed in both groups. Remission rates of type 2 diabetes and hypertension were significantly higher in the surgery group than the lifestyle intervention group; 70 vs 33%, P=0.027, and 49 vs 23%, P=0.016. The improvements in glycaemic control and blood pressure were mediated by weight reduction. The surgery group experienced a significantly greater reduction in the prevalence of metabolic syndrome, albuminuria and electrocardiographic left ventricular hypertrophy than the lifestyle group. Gastrointestinal symptoms and symptomatic postprandial hypoglycaemia developed more frequently after gastric bypass surgery than after lifestyle intervention. There were no deaths. CONCLUSIONS: Type 2 diabetes and obesity-related cardiovascular risk factors were improved after both treatment strategies. However, the improvements were greatest in those patients treated with gastric bypass surgery.

The interleukins IL-6 and IL-1Ra: a mediating role in the associations between BMI and birth weight?

The biological mechanisms in the association between maternal body mass index (BMI) and birth weight are not well understood, but are likely to involve maternal plasma glucose levels and nutrient transport across the placenta, both important modulators of fetal growth. Adipose tissue contributes to circulating levels of interleukins that may affect glucose metabolism and possibly also placental transport of nutrients. We investigated possible mediating roles of Interleukin 6 (IL-6) and Interleukin 1 Receptor antagonist (IL-1Ra) in 208 pregnant women. Known and hypothesized dependencies between BMI in early pregnancy and fasting glucose, IL-1Ra and IL-6 at gestational weeks 30-32, and birth weight were specified in a path diagram. Standardized regression coefficients, expressing direct, indirect and total effects, were estimated by Bayesian path analysis. Mean (s.d.) BMI was 24.9 kg/m2 (4.2) and mean (s.d.) birth weight 3748 g (454). The total effect of BMI on birth weight was 0.24 (95% credibility interval (CrI) [0.12, 0.36]). The direct effect of IL-1Ra on birth weight was not statistically significant, but significant effects of BMI on IL-1Ra (0.61, 95% CrI [0.51, 0.72]), of IL-1Ra on fasting glucose (0.17, 95% CrI [0.01, 0.34]) and of fasting glucose on birth weight (0.14, 95% CrI [0.01, 0.27]) implied an indirect pathway from BMI via IL-1Ra on birth weight. Approximately 20% of the effect of BMI on birth weight was mediated through IL-1Ra. For IL-6, no such effects were found. Our results indicate that IL-1Ra may be a mediator in the association between BMI and birth weight.

A novel method for indirectly monitoring arterial pO(2) during cardiopulmonary bypass.

Arterial blood oxygen tension (P(a)O(2)) is a vital variable that has to be monitored during cardiopulmonary bypass (CPB). The aim of this study was to develop an alternative method for continuously P(a)O(2) monitoring during CPB, based on measurements of exhaust-gas from an oxygenator. A total of 15 adult patients undergoing CPB (n = 81 samples) were included in a study in order to develop an appropriate algorithm for P(a)O(2) estimation based on exhaust gas monitoring of the oxygen tension (P(ex)O(2)). The acquired data was used as a basis for developing a statistical prediction algorithm designed for continuously estimating the P(a)O(2)-level based on exhaust gas data in combination with data from the surrounding medical equipment. A new instrument was developed in order to implement this P(a)O(2) prediction algorithm and was tested on five patients (n = 39 samples). When the first sample was used for calibrating the instrument, the mean (SD) error was 8.7% (7.3%) with a 95% CI of 6.1-11.3%. Our results indicate that a pO(2)-exhaust monitoring device with adequate precision is obtainable, but further studies are required.