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Although several randomized controlled trials (RCTs) have shown the efficacy of antifibrinolytic drugs in liver transplantation, their use remains debated due to concern for thromboembolic complications. None of the reported RCTs has shown a higher incidence of these complications in treated patients; however, none of the individual studies has been large enough to elucidate this issue completely. We therefore performed a systematic review and meta-analysis of efficacy and safety endpoints in all published controlled clinical trials on the use of antifibrinolytic drugs in liver transplantation.Studies were included if antifibrinolytic drugs (eaminocaproic acid, tranexamic acid (TA) or aprotinin) were compared with each other or with controls/placebo. Intraoperative red blood cell and fresh frozen plasma requirements, the perioperative incidence of hepatic artery thrombosis, venous thromboembolic events and mortality were analyzed.We identified 23 studies with a total of 1407 patients which met the inclusion criteria. Aprotinin and TA both reduced transfusion requirements compared with controls. No increased risk for hepatic artery thrombosis, venous thromboembolic events or perioperative mortality was observed for any of the investigated drugs. This systematic review and meta-analysis does not provide evidence for an increased risk of thromboembolic events associated with antifibrinolytic drugs in liver transplantation.

Background -Several studies have shown that both objective and subjective measurements are related to exercise capacity in patients with chronic obstructive pulmonary disease (COPD) (Thorax 1994;49:468-472) Patients with chronic obstructive pulmonary disease (COPD) usually have a decreased exercise tolerance and a reduced quality of life. While spirometric measurements seem to be related to maximum ventilation in a bicycle ergometer performance,' in general they correlate weakly with less stressful tests such as the walking distance.2 5 Moreover, it has been shown that the transfer factor for carbon monoxide (TLCO) is positively correlated with the walking distance test.67Although dynamic and static lung volumes, compliance, and gas transfer (lung function) generally establish the level of impairment in COPD, Mahler and coworkers showed that maximal inspiratory pressure (MIP) provides additional information on impairment.8 Loiseau and coworkers9 also showed that exercise capacity in patients with COPD was related to the impairment of the inspiratory muscles. In addition, it has been shown in other studies that walking distance tests are related to psychosocial measurements, while no relation has been found between psychosocial measurements and bicycle ergometer tests.4 10 11Both objective and subjective measurements are related to exercise capacity in patients with COPD. However, we are not aware of any research on their relative effect on a walking distance test compared with a bicycle ergometer test. In this study we have therefore investigated the relative contribution of lung function, maximal inspiratory pressure, dyspnoea, and quality of life to the performance in a walking distance test as well as a bicycle ergometer test in patients with COPD. Methods PATIENTSForty patients with known COPD"2 (table 1) who started a rehabilitation programme were studied. Entry criteria were: (a) postbronchodilator FEV, (forced expiratory volume in one second) <60% predicted, and (2) postbronchodilator FEV,/IVC (inspiratory vital capacity) <50% (after two inhalations of 40,ug Rehabilitation Centre,

Background -The Chronic Respiratory Questionnaire (CRQ) is frequently applied to assess quality of life in patients with chronic obstructive pulmonary disease (COPD). However, the reliability and validity of this questionnaire have not yet been determined. This study investigates the reliability and validity of the four separate dimensions of the CRQ.Methods -The CRQ was administered on two consecutive days to 40 patients with COPD (mean FEV1 44% predicted, FEVj/ IVC 37% predicted). Internal consistency reliability of each dimension was investigated by Cronbach's a reliability coefficient, test retest reliability by the Spearman-Brown reliability coefficient (p), and content validity by Pearson's correlation coefficient between the CRQ and the symptom checklist (SCL-90). Results -Items of the fatigue, emotion, and mastery dimensions showed a high internal consistency reliability (a = 0-71-0 88) as well as a high test retest reliability (p above 0 90). These three dimensions correlated with comparable dimensions of the SCL-90. Items of the dyspnoea dimension showed a low internal consistency reliability (ox=0-53) and a test retest reliability of p = 0 73. Conclusions -Items of the dimensions fatigue, emotion, and mastery of the CRQ are reliable and valid and can be used to assess quality of life in patients with severe airways obstruction. Items of the dyspnoea dimension are less reliable and should not be included in the overall score of the CRQ in comparative research. However, by scoring the items of dyspnoea separately they may be useful for the evaluation of the effects of intervention in a specific patient. (Thorax 1994;49:465-467) Impaired lung function may, in addition to limiting exercise, result in an impaired quality of life. 1-3 A study by Traver showed that health care use by patients with chronic obstructive pulmonary disease (COPD) was related more to impaired quality of life than to the severity of the disease itself.4 It is therefore important to measure quality of life in COPD as well as lung function and exercise tolerance.Two general health measurements -the Quality of Well Being scale5 and the Sickness Impact Profile6 -were developed for use in these patients. Because these instruments are not sensitive enough to detect small changes7 after treatment, Guyatt and coworkers developed the Chronic Respiratory Questionnaire (CRQ).8 They showed that the CRQ was precise, valid, and responsive,89 but did not investigate the internal consistency reliability of the separate dimensions. Furthermore, responsiveness to change is more an indication of the validity of a measuring instrument than a separate characteristic. '0 This means that reproducible and responsive measurement instruments may contain items which have nothing in common" -that is, the sets of items do not measure the dimensions they constitute. We have therefore investigated the internal consistency and the test retest reliability of the separate dimensions of the CRQ. The content validity of the CRQ was assessed by correlating ...