Lung function in relation to six-minute walk test in pulmonary hypertension.

Background: Pulmonary hypertension (PH) is a progressive disorder of the pulmonary circulation, associated with diverse medical conditions. Exercise limitation is the most prominent symptom in PH. Exercise capacity, commonly assessed through a six-minute walk test (6MWT), correlates with both functional status and survival in PH. Few studies have analysed the relation between respiratory function and exercise limitation. Therefore, we investigated the relationship between resting pulmonary function, exercise capacity, and exertional desaturation, assessed through the 6MWT, in unselected PH patients. Methods: Fifty consecutive patients with PH diagnosis, referred for pulmonary function testing (lung volume, spirometry, and diffusing capacity for carbon monoxide (DLCO)) and 6MWT, were recruited at Molinette University Hospital, Turin. Results: The majority of the patients (54%) had PH due to left heart disease. Airway obstruction (FEV1/VC-ratio < 0.7) was found in 46% of the patients and they performed significantly worse in the 6MWT than unobstructed patients (307 m vs. 377 m). Patients with PH due to left heart disease also performed significantly poorer 6MWT when airway obstruction was present (305 m vs. 389 m). Twenty-two patients (44%) presented exertional desaturation upon 6MWT. Lower DLCO divided by the alveolar volume (DLCO/VA), FEV1/VC-ratios and resting PaO2-values were significantly correlated with exertional desaturation after adjustments for age, sex, BMI, and smoking habits. DLCO/VA was the main determinant of exertional desaturation in a stepwise regression model. Conclusions: Spirometric parameters of airway obstruction were related to walk distance and exercise-induced desaturation in PH patients. This suggests a place for spirometry in clinical monitoring of PH patients.

Pulmonary function in children and adolescents after esophageal atresia repair.

INTRODUCTION: Respiratory morbidity after esophageal atresia (EA) is common. The aims of this study were to assess pulmonary function, to identify risk factors for pulmonary function impairment (PFI), and to investigate the relations between respiratory morbidity, defined as medical treatment for respiratory symptoms or recent pneumonia and PFI after EA repair. MATERIAL AND METHODS: Single center retrospective observational study including patients with EA who participated in the follow-up program for 8- or 15-year old patients from 2014 to 2018 and performed pulmonary function testing by body plethysmography, dynamic spirometry, impulse oscillometry, and diffusing capacity of the lungs. Univariate and multiple stepwise logistic regression with PFI as outcome were performed. Anastomotic leak, episodes of general anesthesia, extubation day, birth weight, age at follow up, gross classification, and abnormal reflux index were independent variables. RESULTS: In total, 47 patients were included. PFI was found in 19 patients (41%) and 16 out of 19 patients (84%) had an obstructive pattern. Respiratory morbidity was found in 23 (52%, NA = 3) of the patients with no correlation to PFI. Birth weight, age at follow-up, and episodes of general anesthesia were identified as risk factors for PFI. CONCLUSION: Respiratory morbidity and PFI were common in children and adolescents after EA repair. The major component of PFI was obstruction of the airways. The risk for PFI increased with lower birth weight and older age at follow up. The poor correlation between respiratory morbidity and PFI motivates the need of clinical follow up including pulmonary function tests.

Effects of Oral Supplementation With Nitrate-Rich Beetroot Juice in Patients With Pulmonary Arterial Hypertension-Results From BEET-PAH, an Exploratory Randomized, Double-Blind, Placebo-Controlled, Crossover Study.

BACKGROUND: The nitrate-nitrite-nitric oxide (NO) pathway may represent a potential therapeutic target in patients with pulmonary arterial hypertension (PAH). We explored the effects of dietary nitrate supplementation, with the use of nitrate-rich beetroot juice (BRJ), in patients with PAH. METHODS AND RESULTS: We prospectively studied 15 patients with PAH in an exploratory randomized, double-blind, placebo-controlled, crossover trial. The patients received nitrate-rich beetroot juice (∼16 mmol nitrate per day) and placebo in 2 treatment periods of 7 days each. The assessments included; exhaled NO and NO flow-independent parameters (alveolar NO and bronchial NO flux), plasma and salivary nitrate and nitrite, biomarkers and metabolites of the NO-system, N-terminal pro-B-type natriuretic peptide, echocardiography, ergospirometry, diffusing capacity of the lung for carbon monoxide, and the 6-minute walk test. Compared with placebo ingestion of BRJ resulted in increases in; fractional exhaled NO at all flow-rates, alveolar NO concentrations and bronchial NO flux, and plasma and salivary levels of nitrate and nitrite. Plasma ornithine levels decreased and indices of relative arginine availability increased after BRJ compared to placebo. A decrease in breathing frequency was observed during ergospirometry after BRJ. A tendency for an improvement in right ventricular function was observed after ingestion of BRJ. In addition a tendency for an increase in the peak power output to peak oxygen consumption ratio (W peak/VO2 peak) was observed, which became significant in patients reaching an increase of plasma nitrite >30% (responders). CONCLUSIONS: BRJ administered for 1 week increases pulmonary NO production and the relative arginine bioavailability in patients with PAH, compared with placebo. An increase in the W peak/VO2 peak ratio was observed after BRJ ingestion in plasma nitrite responders. These findings indicate that supplementation with inorganic nitrate increase NO synthase-independent NO production from the nitrate-nitrite-NO pathway.

Cross-sectional and longitudinal analyses of the association between lung function and exercise capacity in healthy Norwegian men.

BACKGROUND: It is widely accepted that exercise capacity in healthy individuals is limited by the cardiac function, while the respiratory system is considered oversized. Although there is physiological, age-related decline in both lung function and physical capacity, the association between decline in lung function and decline in exercise capacity is little studied. Therefore, we examined the longitudinal association between lung function indices and exercise capacity, assessed by the total amount of work performed on a standardized incremental test, in a cohort of middle-aged men. METHODS: A total of 745 men between 40 and 59 years were examined using spirometry and standardized bicycle exercise ECG test within "The Oslo Ischemia Study," at two time points: once during 1972-1975, and again, approximately 16 years later, during 1989-1990. The subjects exercise capacity was assessed as physical fitness i.e. the total bicycle work (in Joules) at all workloads divided by bodyweight (in kg). RESULTS: Higher FEV1, FVC and PEF values related to higher physical fitness at both baseline and follow-up (all p values < 0.05). Higher explanatory values were found at follow-up than baseline for FEV1 (r2 = 0.16 vs. r2 = 0.03), FVC (r2 = 0.14 vs. r2 = 0.03) and PEF (r2 = 0.13 vs. r2 = 0.02). No significant correlations were found between decline in physical fitness and declines in FEV1, FVC or PEF. CONCLUSIONS: A weak association between lung function indices and exercise capacity, assessed through physical fitness, was found in middle-aged, healthy men. This association was strengthened with increasing age, suggesting a larger role for lung function in limiting exercise capacity among elderly subjects. However, decline in physical fitness over time was not related to decline in lung function.

2017 Global Initiative for Chronic Obstructive Lung Disease reclassifies half of COPD subjects to lower risk group.

Background: Unlike the 2014 guidelines, the 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines have removed lung function from the risk assessment algorithm of patients with COPD. The aim of this investigation was to analyze the proportion of subjects who would change to a lower risk group when applying GOLD2017 and determine if they exhibit different characteristics in terms of inflammation, symptoms and comorbidity compared to the subjects who would remain in a high-risk group. Subjects and methods: A total of 571 subjects with physician-diagnosed and spirometry-verified COPD were included in the present study. The data consisted of measurements of lung function, inflammatory markers, together with questionnaires that covered comorbidities, COPD symptoms and medication. Results: From group C, 53% of the subjects would be reclassified to the lower risk group A, and from group D, 47% of the subjects would be reclassified to the lower risk group B when using GOLD2017 instead of GOLD2014. Compared to the subjects who would remain in group D, those who would change to group B were more often men (56% vs 72%); of an older age, mean (SD), 71 (8) years vs 68 (7) years; had more primary care contact (54% vs 33%); had lower levels of blood neutrophils, geometrical mean (95% CI), 5.3 (5.0, 5.7) vs 4.6 (4.3, 4.9); reported less anxiety/depression (20% vs 34%); experienced less asthma (29% vs 46%) and had fewer symptoms according to the COPD assessment test, 16 (5) vs 21 (7). All p-values were <0.05. Conclusion: The removal of spirometry from risk assessment in GOLD2017 would lead to the reclassification of approximately half of the subjects in the risk groups C and D to the lower risk groups A and B. There are differences in age, gender, health care contacts, inflammation, comorbidity and symptom burden among those changing from group D to group B. The effects of reclassification and changes in eventual treatment for disease control and symptom burden need further investigation.

Exercise capacity in young adults after hematopoietic cell transplantation in childhood.

A symptom-limited incremental cycle ergometer test was performed in 17 young adult patients treated with hematopoietic cell transplantation and total body irradiation for hematologic malignancies during childhood. These 17 young adult patients were compared with 17 sex- and age-matched healthy control subjects. Assessments of pulmonary function, cardiac function, body composition, and levels of growth hormone were made. The median follow-up was 17.7 years. Patients achieved 63.2% of the predicted peak workload, whereas controls achieved 96.1% (P < .001). All patients, but only 1 control, failed to achieve a peak workload >80% (P < .001). Fat-free mass was significantly lower (43.5 vs 57.6 kg, P < .001) and fat mass percentage was significantly higher (31.8% vs 24.2%, P = .011) in the patients. The peak workload adjusted for fat-free mass was significantly lower in the patients (3.3 vs 4.3, P < .001). In the patients, peak workload correlated significantly with total lung capacity (r = .54, P = .025). In summary, long-term survivors have significantly decreased exercise capacity compared with healthy individuals. Together with their altered body composition, this may predispose them to cardiovascular disease.

Eight-year follow-up of airway hyperresponsiveness in patients with primary Sjögren's syndrome.

OBJECTIVE: To evaluate in a longitudinal study the influence of airway hyperresponsiveness (AHR) on lung function in patients with primary Sjögren's syndrome (pSS). METHODS: Lung function was studied over an eight-year period in 15 patients who fulfilled the Copenhagen criteria for primary Sjögren's syndrome and who were covered in our earlier published study on AHR in patients with Sjögren's syndrome. Standard spirometry and measurements of lung volumes, diffusing capacity (DLCO), and AHR to methacholine were performed. RESULTS: A significant decline over time was found in total lung capacity (TLC), vital capacity (VC), forced vital capacity (FVC), functional residual capacity (FRC), and expiratory midflows (FEF50). A sign of small airway obstruction (decrease in FEF50) at entry correlated with VC at follow-up (r = .8, P < .003), and the individual change in FEF50 during the observation period correlated with the individual change in VC (r = .6, P < .05). Six patients had increased AHR, and three of them had decreased DLCO. Six of the patients progressively reduced DLCO over time, and five of them had spirometric signs of increased small airway obstruction. CONCLUSIONS: During this eight-year follow-up we observed that one-third of the patients with pSS developed a significant reduction in lung function. Our findings suggest that small airways obstruction and AHR are associated with reduction of VC and development of impaired DLCO as a sign of interstitial lung disease in this group of patients.

Respiratory muscle strength is not decreased in patients undergoing cardiac surgery.

BACKGROUND: Postoperative pulmonary impairments are significant complications after cardiac surgery. Decreased respiratory muscle strength could be one reason for impaired lung function in the postoperative period. The primary aim of this study was to describe respiratory muscle strength before and two months after cardiac surgery. A secondary aim was to describe possible associations between respiratory muscle strength and lung function. METHODS: In this prospective observational study 36 adult cardiac surgery patients (67 ± 10 years) were studied. Respiratory muscle strength and lung function were measured before and two months after surgery. RESULTS: Pre- and postoperative respiratory muscle strength was in accordance with predicted values; MIP was 78 ± 24 cmH2O preoperatively and 73 ± 22 cmH2O at two months follow-up (p = 0.19). MEP was 122 ± 33 cmH2O preoperatively and 115 ± 38 cmH2O at two months follow-up (p = 0.18). Preoperative lung function was in accordance with predicted values, but was significantly decreased postoperatively. At two-months follow-up there was a moderate correlation between MIP and FEV1 (r = 0.43, p = 0.009). CONCLUSIONS: Respiratory muscle strength was not impaired, either before or two months after cardiac surgery. The reason for postoperative lung function alteration is not yet known. Interventions aimed at restore an optimal postoperative lung function should focus on other interventions then respiratory muscle strength training.

Measuring breathing patterns and respiratory movements with the respiratory movement measuring instrument.

INTRODUCTION: The respiratory movement measuring instrument (RMMI) is a laser-based non-invasive technique to measure breathing patterns and respiratory movements (RMs). Little knowledge is known about the ability of the RMMI to measure breathing patterns and the correlation between RMs and breathing volumes. OBJECTIVES: One aim was to investigate whether the RMMI could discriminate between normal versus abdominal versus high costal breathing patterns in different body positions. A second aim was to determine the correlation between RMs and breathing volumes in different body positions. METHOD: Twenty adult, healthy subjects (10 women) were included in the study. The RMMI was used to study the above-mentioned breathing patterns in supine, sitting and standing positions. A subgroup of 12 subjects (6 women) simultaneously performed measurements of breathing volumes while RMs were recorded. RESULTS: The RMMI was able to discriminate between different breathing patterns in different body positions (P<0·001). The upper thoracic contribution to RMs in the sitting position was 47% for natural breathing, 32% for abdominal breathing and 64% for high costal breathing; similar results were found in the supine and standing positions. A strong correlation was observed between RMs as measured by the RMMI and different breathing volumes in all three body positions (Spearman's rho 0·86-1·00). CONCLUSION: The RMMI can be used to measure and analyse different breathing patterns in different body positions, and the correlation between measured RMs and breathing volumes is strong.

Exercise test using dry air in random adolescents: Temporal profile and predictors of bronchoconstriction.

BACKGROUND AND OBJECTIVE: Guidelines recommend exercise tests using dry air to diagnose exercise-induced bronchoconstriction (EIB). Lung function changes subsequent to these tests have not been investigated in a general adolescent population, and it remains unknown whether signs of airway inflammation, measured using exhaled nitric oxide (FeNO), can predict a positive response. The aim of this study was to investigate the temporal aspect of decline in forced expiratory volume in 1 s (FEV1 ) after an exercise test using dry air, and to investigate predictors of EIB. METHODS: From a cross-sectional study on adolescents aged 13-15 years (n = 3838), a random subsample of 146 adolescents (99 with and 47 without self-reported exercise-induced dyspnoea) underwent standardized treadmill exercise tests for EIB while breathing dry air. RESULTS: Of the adolescents, 34% had a positive EIB test (decline of ≥10% in FEV1 from baseline) within 30 min. Of the subjects with EIB, 53% showed the greatest decline in FEV1 at 5 to 10 min (mean decline 18.5%), and the remaining 47% of the subjects showed the greatest decline at 15 to 30 min (mean decline 18.9%) after exercise. Increased FeNO (>20 ppb), female gender and self-reported exercise-induced dyspnoea were independently associated with a positive EIB test. CONCLUSION: When assessing general adolescents for EIB with exercise test using dry air, there is a temporal variation in the greatest FEV1 decline after exercise. Therefore, lung function should be measured for at least 30 min after the exercise. Increased FeNO, female gender and self-reported exercise-induced dyspnoea can be predictors of a positive EIB test.

Impaired Carbon Monoxide Diffusing Capacity is the strongest lung function predictor of decline in 12 minute-walking distance in COPD; a 5-year follow-up study.

BACKGROUND: The purpose of this study was to evaluate the longitudinal relationship between functional exercise capacity, assessed through standardized 12-minute walk test (12MWT), and various lung function parameters obtained using spirometry, body plethysmography and diffusing capacity (DLco) measurements in patients with COPD. METHODS: Spirometry, body plethysmography and DLco-measurements were performed at baseline in 84 subjects with moderate to very severe COPD and at follow-up visit (n = 34) after 5 years. Functional exercise capacity was determined using standardized 12MWT. RESULTS: Patients were characterized at baseline by FEV1 of 1.2 ± 0.4 L (41 ± 13% predicted), RV of 3.4 ± 1.0 L (187 ± 58% predicted) and DLco of 3.8 ± 1.2 mmol/min/kPa (51 ± 16% predicted). A decrease of 12MWD was found between baseline and follow-up (928 ± 193 m vs. 789 ± 273 m, p < 0.001). DLco and 12MWD at baseline were the only independent predictors of 12MWD at follow-up in a multiple logistic regression model that also included all other lung function parameters, gender, age and BMI. Decline in 12MWD was mainly explained by deterioration in DLco. Furthermore, DLco value at baseline had the highest explanatory value for the loss in 12MWD after 5 years (R2 = 0.18, p = 0.009). CONCLUSIONS: In a 5-year longitudinal study, DLco-measurements at baseline were the most important predictors of declining exercise capacity in COPD patients. These results suggest that integration of DLco in the clinical workup provides a more comprehensive assessment in patients with COPD.

Deep breathing exercises performed 2 months following cardiac surgery: a randomized controlled trial.

PURPOSE: Postoperative breathing exercises are recommended to cardiac surgery patients. Instructions concerning how long patients should continue exercises after discharge vary, and the significance of treatment needs to be determined. Our aim was to assess the effects of home-based deep breathing exercises performed with a positive expiratory pressure device for 2 months following cardiac surgery. METHODS: The study design was a prospective, single-blinded, parallel-group, randomized trial. Patients performing breathing exercises 2 months after cardiac surgery (n = 159) were compared with a control group (n = 154) performing no breathing exercises after discharge. The intervention consisted of 30 slow deep breaths performed with a positive expiratory pressure device (10-15 cm H2O), 5 times a day, during the first 2 months after surgery. The outcomes were lung function measurements, oxygen saturation, thoracic excursion mobility, subjective perception of breathing and pain, patient-perceived quality of recovery (40-Item Quality of Recovery score), health-related quality of life (36-Item Short Form Health Survey), and self-reported respiratory tract infection/pneumonia and antibiotic treatment. RESULTS: Two months postoperatively, the patients had significantly reduced lung function, with a mean decrease in forced expiratory volume in 1 second to 93 ± 12% (P< .001) of preoperative values. Oxygenation had returned to preoperative values, and 5 of 8 aspects in the 36-Item Short Form Health Survey were improved compared with preoperative values (P< .01). There were no significant differences between the groups in any of the measured outcomes. CONCLUSION: No significant differences in lung function, subjective perceptions, or quality of life were found between patients performing home-based deep breathing exercises and control patients 2 months after cardiac surgery.

Impaired carbon monoxide diffusing capacity is the strongest predictor of exercise intolerance in COPD.

BACKGROUND: Exercise intolerance is a hallmark of chronic obstructive pulmonary disease (COPD) and forced expiratory volume in one second (FEV1) is the traditional metric used to define the severity of COPD. However, there is dissociation between FEV1 and exercise capacity in a large proportion of subjects with COPD. The aim of this study was to investigate whether other lung function parameters have an additive, predictive value for exercise capacity and whether this differs according to the COPD stage. METHODS: Spirometry, body plethysmography and diffusing capacity for carbon monoxide (DLCO) were performed on 88 patients with COPD GOLD stages II-IV. Exercise capacity (EC) was determined in all subjects by symptom-limited, incremental cycle ergometer testing. RESULTS: Significant relationships were found between EC and the majority of lung function parameters. DLCO, FEV1 and inspiratory capacity (IC) were found to be the best predictors of EC in a stepwise regression analysis explaining 72% of EC. These lung function parameters explained 76% of EC in GOLD II, 72% in GOLD III and 40% in GOLD IV. DLCO alone was the best predictor of exercise capacity in all GOLD stages. CONCLUSIONS: Diffusing capacity was the strongest predictor of exercise capacity in all subjects. In addition to FEV1, DLCO and IC provided a significantly higher predictive value regarding exercise capacity in COPD patients. This suggests that it is beneficial to add measurements of diffusing capacity and inspiratory capacity when clinically monitoring COPD patients.

Lung Function before and Two Days after Open-Heart Surgery.

Reduced lung volumes and atelectasis are common after open-heart surgery, and pronounced restrictive lung volume impairment has been found. The aim of this study was to investigate factors influencing lung volumes on the second postoperative day. Open-heart surgery patients (n = 107, 68 yrs, 80% male) performed spirometry both before surgery and on the second postoperative day. The factors influencing postoperative lung volumes and decrease in lung volumes were investigated with univariate and multivariate analyses. Associations between pain (measured by numeric rating scale) and decrease in postoperative lung volumes were calculated with Spearman rank correlation test. Lung volumes decreased by 50% and were less than 40% of the predictive values postoperatively. Patients with BMI >25 had lower postoperative inspiratory capacity (IC) (33 ± 14% pred.) than normal-weight patients (39 ± 15% pred.), (P = 0.04). More pain during mobilisation was associated with higher decreases in postoperative lung volumes (VC: r = 0.33, P = 0.001; FEV(1): r = 0.35, P ≤ 0.0001; IC: r = 0.25, P = 0.01). Patients with high BMI are a risk group for decreased postoperative lung volumes and should therefore receive extra attention during postoperative care. As pain is related to a larger decrease in postoperative lung volumes, optimal pain relief for the patients should be identified.

A longitudinal study of pulmonary function after stem cell transplantation, from childhood to young adulthood.

BACKGROUND: Impairment of pulmonary function after stem cell transplantation (SCT) in childhood has been reported before. However, long-term longitudinal studies are scarce. PROCEDURE: We measured lung volumes and performed dynamic spirometry serially in 18 patients after SCT. At the last investigation, a median of 18.2 years after SCT, the patients were compared with 18 matched controls. The diffusing capacity (DLCO) was only compared cross-sectionally. RESULTS: There was a significant increase in the prevalence of restrictive lung disease (RLD, total lung capacity <80% of that predicted) from 7% (1/14) before SCT to 28% (5/18) 5 years after SCT, and 61% (11/18) a median of 18.2 years after SCT (P = 0.002). In comparison, none of the controls had RLD (61% vs. 0%, P = 0.001). Before SCT, no patient had obstructive lung disease (OLD, forced expiratory volume in 1 sec/vital capacity <70). OLD was found in one of 18 patients (6%) 5 years after SCT but in none of the patients a median of 18.2 years after SCT. Three of the controls had OLD (P = 0.25). Eleven patients had diffusion impairment (DLCO <80% of that predicted), as opposed to none of the controls (P = 0.001). The DLCO corrected for alveolar volume was decreased in only two patients. CONCLUSION: We documented an increase in the prevalence of RLD, but not of OLD, after SCT. At the last investigation, only two patients had diffusion impairment after correction for alveolar volume.

Wireless pH-metry at the gastrojejunostomy after Roux-en-Y gastric bypass: a novel use of the BRAVO™ system.

BACKGROUND: The number of gastric bypass operations being performed is increasing rapidly due to good weight loss and alleviation of comorbidities in combination with low mortality and morbidity. Stomal ulcers are, however, a clinical problem after gastric bypass, giving patients discomfort, risk of bleeding, or even perforation. To measure the acidity in the proximal jejunum, we adopted the wireless pH-metry (BRAVO™ system) developed for evaluating reflux esophagitis. METHODS: Twenty-five patients (4 men; median age, 44 years; body mass index, 29.3) who had undergone Roux-en-Y gastric bypass (RYGBP) 4 years earlier were recruited. Twenty-one asymptomatic, non-proton pump inhibitor (PPI) users, and in addition, four symptomatic patients (ongoing or stopped PPI treatment) were studied. The wireless BRAVO™ capsule was positioned at the level of the gastrojejunal anastomosis under visual control with the endoscope. pH was registered for up to 48 h. Time with pH<4 was calculated. Two patients were studied with two capsules. RESULTS: Of the 25 recruited patients, capsule placement was successful in all but two patients, and in three patients a constant neutral environment was seen before a premature loss of signal, indicating early loss of position. Thus, 20 successful measurements were made. The mean time of registration was 25.7 (range, 6.1-47.4) h (n=20). In the 16 asymptomatic patients, median percentage of time with pH<4 at the gastrojejunostomy was 10.5% (range, 0.4-37.7%). When dividing the registration time in day (06.00-22.00) and night (22.00-06.00), the median percentage of time with pH<4 was 8.4 and 6.3, respectively (p=0.08). The two double measurements gave similar results indicating consistency. No complications occurred. CONCLUSIONS: Wireless pH measurements in the proximal jejunum after gastric bypass are feasible and safe. The acidity was significant (10.5% of the registration time) even in asymptomatic patients with small gastric pouches. The described method could be useful in evaluation of epigastralgia after gastric bypass and in appraisal of PPI treatment of stomal ulcer.

Gastric emptying and postprandial PYY response after biliopancreatic diversion with duodenal switch.

BACKGROUND: Super-obesity (BMI > 50) is increasing rapidly. We use the biliopancreatic diversion with duodenal switch (BPD-DS) as one option in this patient category. The aim of the present study was to investigate the emptying of the gastric tube, PYY levels and dumping symptoms after BPD-DS. METHODS: Emptying of the gastric tube was investigated with scintigraphy after an overnight fast. Twenty patients (median age 43 years, BMI 31.1 kg/m²) having undergone BPD-DS in median 3.5 years previously were included in the scintigraphic study. A technetium-labelled omelette was ingested and scintigraphic evaluation of gastric emptying was undertaken. Ten of the patients also underwent PYY measurements after a standardised meal and were compared to nine non-operated age-matched normal weight controls, both in the fasting state and after the test meal. Frequency of dumping symptoms was evaluated in all patients. RESULTS: The half-emptying time was 28 ± 16 min. Lag phase was present in 30% of the patients. PYY levels were significantly higher in BPD-DS patients as compared to controls both in the fasting state (p < 0.001) and after the test meal (p < 0.001). Dumping symptoms were scarce and occurred in 17 of the 20 patients only few times yearly or less. CONCLUSIONS: Although the pylorus is preserved in BPD-DS, the stomach emptying is faster than in non-operated subjects. PYY levels are elevated in the fasting state after BPD-DS and a marked response to a test meal is seen, likely due to the rapid stimulation of intraluminal nutrients in the distal ileum. In spite of this, dumping symptoms are uncommon.

Deep breathing exercises with positive expiratory pressure at a higher rate improve oxygenation in the early period after cardiac surgery--a randomised controlled trial.

OBJECTIVE: In addition to early mobilisation, a variety of breathing exercises are used to prevent postoperative pulmonary complications after cardiac surgery. The optimal duration of the treatment is not well evaluated. The aim of this study was to determine the effect of 30 versus 10 deep breaths hourly, while awake, with positive expiratory pressure on oxygenation and pulmonary function the first days after cardiac surgery. METHODS: A total of 181 patients, undergoing cardiac surgery, were randomised into a treatment group, performing 30 deep breaths hourly the first postoperative days, or into a control group performing 10 deep breaths hourly. The main outcome measurement arterial blood gases and the secondary outcome pulmonary function, evaluated with spirometry, were determined on the second postoperative day. RESULTS: Preoperatively, both study groups were similar in terms of age, SpO(2), forced expiratory volume in 1s and New York Heart Association classification. On the second postoperative day, arterial oxygen tension (PaO(2)) was 8.9 ± 1.7 kPa in the treatment group and 8.1 ± 1.4 kPa in the control group (p = 0.004). Arterial oxygen saturation (SaO(2)) was 92.7 ± 3.7% in the treatment group and 91.1 ± 3.8% in the control group (p = 0.016). There were no differences in measured lung function between the groups or in compliance to the breathing exercises. Compliance was 65% of possible breathing sessions. CONCLUSIONS: A significantly increased oxygenation was found in patients performing 30 deep breaths the first two postoperative days compared with control patients performing 10 deep breaths hourly. These results support the implementation of a higher rate of deep breathing exercises in the initial phase after cardiac surgery.

How often is diagnosis of COPD confirmed with spirometry?

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an important cause of morbidity and mortality worldwide. Diagnosis is customarily confirmed with spirometry, but there are few studies on documented spirometry use in everyday clinical practice. METHODS: In a cross-sectional survey and study of the medical records of primary and secondary care COPD patients aged 18-75 in a Swedish region, patients with COPD were randomly selected from the registers of 56 primary care centres and 14 hospital outpatient clinics. Spirometry data at diagnosis +/-6 months were analyzed. RESULTS: From 1114 patients with COPD, 533 with a new diagnosis of COPD during the four-year study period were identified. In 59% (n=316), spirometry data in connection with diagnosis were found in the medical records. Spirometry data with post-bronchodilator forced expiratory volume in 1s (FEV(1))/ vital capacity (VC) ratios were available in 45% (n=241). FEV1/VC ratio <0.70 were found in 160 patients, which corresponds to 30% of the patients with a new diagnosis. Lower age, female gender, current smoking, higher body mass index (BMI) and shorter forced exhalation time were related to COPD diagnosis despite an FEV(1)/VC ratio of >/=0.70. The most common problem in the quality assessment was an insufficient exhalation time. CONCLUSIONS: Only a third of Swedish patients with COPD had their diagnosis confirmed with spirometry. Our data indicate that female gender, current smoking, higher BMI and short exhalation time increase the risk of being diagnosed with COPD without fulfilling the spirometric criteria for the disease.