Using the lower limit of normal for the FEV1/FVC ratio reduces the misclassification of airway obstruction.

AIM: The prevalence of airway obstruction varies widely with the definition used. OBJECTIVES: To study differences in the prevalence of airway obstruction when applying four international guidelines to three population samples using four regression equations. METHODS: We collected predicted values for forced expiratory volume in 1 s/forced vital capacity (FEV(1)/FVC) and its lower limit of normal (LLN) from the literature. FEV(1)/FVC from 40 646 adults (including 13 136 asymptomatic never smokers) aged 17-90+years were available from American, English and Dutch population based surveys. The prevalence of airway obstruction was determined by the LLN for FEV(1)/FVC, and by using the Global Initiative for Chronic Obstructive Lung Disease (GOLD), American Thoracic Society/European Respiratory Society (ATS/ERS) or British Thoracic Society (BTS) guidelines, initially in the healthy subgroup and then in the entire population. RESULTS: The LLN for FEV(1)/FVC varied between prediction equations (57 available for men and 55 for women), and demonstrated marked negative age dependency. Median age at which the LLN fell below 0.70 in healthy subjects was 42 and 48 years in men and women, respectively. When applying the reference equations (Health Survey for England 1995-1996, National Health and Nutrition Examination Survey (NHANES) III, European Community for Coal and Steel (ECCS)/ERS and a Dutch population study) to the selected population samples, the prevalence of airway obstruction in healthy never smokers aged over 60 years varied for each guideline: 17-45% of men and 7-26% of women for GOLD; 0-18% of men and 0-16% of women for ATS/ERS; and 0-9% of men and 0-11% of women for BTS. GOLD guidelines caused false positive rates of up to 60% when applied to entire populations. CONCLUSIONS: Airway obstruction should be defined by FEV(1)/FVC and FEV(1) being below the LLN using appropriate reference equations.

The diffusing capacity in adult cystic fibrosis.

The value of adjusting the diffusing capacity for the lung volume has been demonstrated in a large number of patients with other lung diseases but has not been validated in patients with cystic fibrosis (CF). Pulmonary function test results on a cohort of 52 adult CF patients were analyzed to determine whether the diffusing capacity of carbon monoxide by single breath method (DLCO(SB)) when adjusted for alveolar volume (V(A)%), correlated with the severity of pulmonary dysfunction. The DLCO(SB) remained within the reference range except in those with severe lung impairment (61.88 +/- 15.48%). DLCO(SB) has a significant (P < 0.05) positive correlation (0.70, 0.67, 048, 0.69 and 0.31, respectively) with measures of airflow limitation (FVC%, FEV1%, FEV1/FVC%, MVV%, and sGaw) and negative correlation (-0.36 and -0.21, respectively) with measures of air trapping (RV% and RV/TLC%). DLCO(SB)/V(A) remained above 100% of predicted despite worsening lung disease and did not correlate with other measures of lung function. On the other hand, the DLCO(SB) and DLCO(SB)/V(A), when adjusted for V(A)%, decreased and were significantly correlated with worsening airflow limitation and, to a lesser extent, air trapping. The relatively preserved adjusted DLCO(SB) and DLCO(SB)/V(A) values in CF patients up until late in its course may be explained the predominant airway involvement, minimal loss of alveolar-capillary units, and enhanced V/Q relationship due to claustration in CF.

Thoracoscopic lung volume reduction surgery reduces dyspnea and improves exercise capacity in patients with emphysema.

Improved ventilation and exercise capacity follows thoracoscopic lung volume reduction surgery (TLVRS) in patients with severe emphysema. This improvement could be related to changes in inspiratory and expiratory flows following surgery, with consequent improvement in dyspnea indices. Changes in inspiratory/expiratory flows at rest and exercise and their relation to subjective improvement in dyspnea after TLVRS are not well known. We studied 25 patients with severe emphysema who underwent unilateral TLVRS performed in well-defined zones with decreased perfusion in nuclear medicine lung scans. Early follow-up after surgery (4.2 +/- 0.8 mo) showed significant improvements in exercise tolerance: The distance covered over a 6 min walk test increased from 934 +/- 297 to 1,071 +/- 241 ft (p = 0.01). Exercise tolerance using a bicycle ergometer showed increased exercise endurance from 4.43 +/- 1.7 to 5.71 +/- 1.8 min (p < 0.001). The maximum workload tolerated increased from 37 +/- 19 to 52 +/- 21 W (p < 0.01) and VO2 max changed from 9.7 +/- 2 to 11.8 +/- 3 (ml.kg)/min (p < 0.01). This increment was achieved by generating significantly larger minute ventilation (VE), from 24 +/- 11 to 29 +/- 10 L/min, reached through larger tidal volumes (increasing from 951 +/- 330 to 1,145 +/- 367 ml), while maintaining the same maximum respiratory rates. Increased VE was also accompanied by significant increases in both average inspiratory and expiratory flows measured during exercise: from 0.89 +/- 0.41 L/s to 1.06 +/- 0.08 L/s, and from 0.77 +/- 0.37 to 0.90 +/- 0.32 L/s respectively (p < 0.01). The parallel increment in flows resulted in constant T1/Ttot relationship. These functional changes correlated with increased inspiratory flows at rest measured with pulmonary function tests (forced inspiratory volume in one s [FIV1], expiratory flows [FVC, FEV1], and increased maximum voluntary ventilation [MVV]) following the surgically induced reduction in residual volume (RV). These objective changes occurred parallel to improved dyspnea indices. The Baseline Focal Score was 3.36 +/- 1.47 and the Transition Focal Score was 6.12 +/- 0.7. The objectively measured variables at rest that best correlated with subjective improvement in dyspnea were the change in MVV, change in resting arterial PaO2, and change in FEV1 following TLVRS. Exercise variables did not have significant correlation with subjective markers indicating improvement in dyspnea, with the exception of the change in Dyspneic Index [(VE/MVV)100] at maximum exercise.

Spirometry.

Spirometry is the most widely used pulmonary function test. It is used for diagnosis and monitoring in a wide variety of obstructive and restrictive disease patterns. Spirometry is the primary measure in determining disability due to pulmonary disease, and is widely applied in the evaluation of bronchodilator response and airway hyperreactivity. A wide variety of spirometry equipment is currently available, from small portable units to large laboratory systems capable of multiple functions. Most spirometers rely heavily on computerization, which makes them easy to use, but require training and experience on the part of the user. Valid spirometry demands equipment that conforms to recommended standards, and performance of the tests to meet criteria for acceptability and reproducibility. Interpretation of spirometry requires attention to these standards and to careful selection of reference values.

Hemodynamics and gas exchange after single lung transplantation and unilateral thoracoscopic lung reduction.

BACKGROUND: Single lung transplantation and recently thoracoscopic lung reduction (TLR) have become surgical alternatives to manage emphysema. We report here early outcomes of 10 single lung transplant (SLT) recipients with severe emphysema compared with 10 patients treated with unilateral TLR. METHODS: Ten consecutive recipients of (SLT) and 10 patients undergoing unilateral TLR were studied. Both groups had measurements of preoperative pulmonary function and arterial blood gases. Hemodynamic measurements were made by use of a right ventricular ejection fraction/volumetric pulmonary artery catheter during and immediately after surgery in both groups to compare hemodynamic and gas exchange response in each procedure. Pulmonary function tests were repeated 3 months and 1 year after surgery. Complications and functional outcome are reported. RESULTS: Both groups had the same severity of obstructive disease (mean forced expiratory volume in 1 second = 20% +/- 5% for the SLT group and 23% +/- 9% for the TLR group) and similar patterns of right ventricular dysfunction. During operation, SLT recipients showed worse hypercapnia and pulmonary hypertension than TLR subjects when ventilation and perfusion to the operative lung were interrupted. Patients undergoing TLR only had interrupted ventilation, which was transiently reversed when severe hypoventilation or hypoxemia occurred. All patients undergoing TLR were extubated immediately after surgery. SLT recipients were extubated an average of 42 hours later. Pulmonary function testing performed 3 months after surgery showed improvement in both groups. SLT recipients showed larger improvements in airflow but comparable improvements in forced vital capacity. Both groups achieved similar improvements in gas exchange. This trend continued a year after surgery. Patients undergoing TLR were not subjected to complications of immunosuppressive therapy or exposed to opportunistic infections. CONCLUSIONS: Early results show TLR as an acceptable alternative to SLT in carefully selected patients with the same severity of obstructive lung disease. Long-term follow-up studies are needed to establish long-term differences in functional outcome and development of complications. TLR may be an option for patients with severe dyspnea related to emphysema who do not meet criteria for transplantation.

[Method of gunshot liver wound suturing]. / Sposob ushivaniia ognestrel'noí rany pecheni.

A clinical case of using an original staple with the "shape memory" for hemostasis of a hepatic gunshot injury is described. This method gives possibility to remove the syaple out in the postoperative period.

Unilateral video-assisted thoracic surgical lung reduction.

BACKGROUND: Lung reduction has been demonstrated to be a promising treatment for end-stage emphysema when performed on both lungs via sternotomy. The role for a thoracoscopic approach has not yet been determined. METHODS: Unilateral video-assisted thoracic surgical lung reduction was performed on 50 patients for the treatment of end-stage emphysema. There were 34 men and 16 women with a mean age of 61.5 years (range, 31 to 78 years). Emphysema was secondary to smoking in 45 patients (90%), and alpha 1-antitrypsin deficiency in 5 patients (10%), 4 of whom had smoked in the past. Lung reduction was performed unilaterally using a thoracoscope and a stapled resection without the routine use of bovine pericardium. The side to be operated on and site of resection were determined preoperatively by examination of the perfusion and computed tomographic scans of the lungs. The average amount of lung removed was 59 +/- 15 g (range, 29 to 111 g). RESULTS: Morbidity included prolonged air leak in 15 patients (30%), bleeding in 3 (6%), pneumonia requiring reintubation in 3 (6%), myocardial infarction in 1 (2%), and perforated ulcer in 1 (2%). Seven patients (14%) required a second thoracic procedure for management of these complications. Two patients died, for an operative mortality of 4%. Follow-up obtained between 1 and 3 months in 25 patients revealed significant improvement in forced expiratory volume in 1 second (0.71 to 0.95 L; p < 0.001), forced vital capacity (2.24 to 2.58 L; p < 0.01), and oxygen tension (59 to 67 mm Hg; p < 0.01). The improvement in functional capacity as measured by 6-minute walk approached statistical significance (771 to 923 ft; p = 0.06). CONCLUSIONS: Significant subjective improvement in dyspnea has been noted in 41 of 48 hospital survivors (85%). For patients with end-stage emphysema, unilateral video-assisted thoracic surgical lung reduction appears to be a preferable alternative to standard medical management.

Right ventricular function in patients with severe COPD evaluated for lung transplantation. Lung Transplant Group.

Right ventricular function was measured in ten patients with severe COPD (mean FEV1 = 0.48 +/- 0.2 L/s) as part of an evaluation for single lung transplant (SLT). Right ventricular ejection fraction (RVEF) was determined by two methods: first-pass radionuclide scan by multigated acquisition (MUGA) and by using a fast thermistor tipped RVEF/volumetric pulmonary artery catheter. None of the patients had clinical evidence of active right heart failure, although mild resting pulmonary hypertension (mean pulmonary artery pressure [PAP] = 24 +/- 4 mm Hg) that worsened with minimal exercise (mean PAP = 39 +/- 11 mm Hg) was present. There was a significant difference in RVEF measured by the two methods (mean MUGA RVEF = 57 +/- 10%, mean catheter RVEF = 27 +/- 8%; p < 0.00005). RVEF determined by both methods was correlated with hemodynamic and gas exchange variables obtained during rest and at maximal exercise. There were significant, yet inverse, correlations between RVEF measured by catheter and cardiac index measured during exercise (CIex), as well as with exercise pulmonary vascular resistance index (PVRI). There were no significant correlations found between MUGA RVEF and any gas exchange or hemodynamic variables. Significant correlations were found with the catheter-measured right ventricular end-diastolic volume (RVEDV) and CIex (r = 0.9 p < 0.005), with maximal oxygen consumption during exercise (VO2max) (r = 0.86 p < 0.0025), with exercise stroke volume index (SVI) (r = 0.76 p < 0.01), and exercise central venous pressure (CVP) (r = 0.62 p < 0.05). Echocardiographic studies revealed right ventricular dilatation and mild tricuspid regurgitation (TR) in all patients. The strong correlation between RVEDV, CIex, and VO2max supports the concept that in these patients, as long as there is no clinical evidence of right heart failure (resting CVP still within normal limits), those with the largest RVEDVs use the Frank Starling principle to their best advantage to remain more functional.(ABSTRACT TRUNCATED AT 400 WORDS)

The blue light-responsive AthH2 gene of Arabidopsis thaliana is primarily expressed in expanding as well as in differentiating cells and encodes a putative channel protein of the plasmalemma.

According to our previous studies the Arabidopsis gene AthH2 which is inducible by blue light and phytohormones codes for an intrinsic membrane protein. It bears a resemblance to several distinct channel proteins of plant and animal species classified as the MIP/NOD-26/GlpF family. In the present study biochemical analyses and electron microscopic immunochemistry were used to elucidate the subcellular location of the AthH2 protein. The results clearly demonstrate that it is an exclusive constituent of the plasmalemma. Furthermore, the expression of the AthH2 gene in transgenic Arabidopsis plants containing the promoter region of AthH2 fused to the beta-glucuronidase (gus) reporter gene was studied. The in situ localization of gus activity revealed that the specific promoter is temporally activated by light in expanding and/or differentiating cells comprising newly formed tissues and organs: root elongation zone, guard cells of stomata, vascular bundle sheaths, filaments of stamen and young siliques. Several sites of gus expression coincide spatially with those of in situ hybridization and the immunocytochemical reaction, respectively, suggesting that the AthH2 promoter had correctly responded to light as an important exogenous factor with relevance to the complex pattern of differentiation. Studies with protoplasts from plants transformed with an antisense construct revealed a water transport capacity of the AthH2 protein.

[Hemostasis in deep injuries of the liver]. / Gemostaz pri glubokikh raneniiakh pecheni.

Experimental and clinical substantiation of the use of an original alloyed staple with shape memory allowed it to be recommended for closure of deep wounds of the liver when all other known methods and constructions are ineffective. The staple causes a lesser zone of necrosis than that produced by catgut in closure of a similar wound, and it can be removed with no loss of blood. Consequently, its application is a method of today, causes little injury, and is promising.