Co-infected HIV/hepatitis patients compared with chronic liver patients and healthy individuals: respiratory assessment through surface electromyography and spirometry.

INTRODUCTION: Co-infected HIV and hepatitis subjects are candidates for a liver transplantation because of progressive liver disease. Chronic liver disease, co-infected or not, requires assessment of respiratory function before liver transplantation. The respiratory evaluation of these 2 groups compared with healthy individuals can define deficits, and this can impair a full recovery after transplant surgery. OBJECTIVE: This study sought to compare the respiratory profile in co-infected patients with chronic liver disease who are candidates for liver transplantation with that of healthy subjects. METHODS: Through respiratory evaluation of flows and lung volumes (spirometry), muscle activity (surface electromyography), and maximum pressure (manovacuometer), 250 people were distributed into 3 groups: 14 patients with HIV and liver disease, 65 healthy subjects, and 171 patients with chronic liver disease. The mean age (years) was respectively 47.5 ± 6.2, 48.3 ± 14.1, and 52.9 ± 8.5. The average body mass index (kg/m(2)) of the groups was 24.6 ± 4.5, 26.0 ± 3.2, and 28.5 ± 5.3, respectively. RESULTS: There was a statistical difference among the groups in the root means square (RMS) rectus abdominis (µV) (P = .0016), RMS diaphragm (µV) (P = .0001), maximal inspiratory pressure (cmH2O) (P = .001), forced exhaled volume at the end of first second (%) (P = .002), and maximal mid expiratory flow 25% to 75% (%) (P = .0001) for the Kruskal-Wallis test. The multivariate analysis among the groups showed that the RMS diaphragm had a tendency to discriminate the co-infected subjects. CONCLUSIONS: The co-infected HIV group showed a muscle deficit of diaphragm and rectus abdominis activity, and the liver disease group showed lower indexes in volumes and respiratory flows.

Correlation between functional capacity and respiratory assessment of end-stage liver disease patients waiting for transplant.

INTRODUCTION: End-stage liver disease has metabolic complications associated with malnutrition, which involves a great loss of muscle mass. This complication can lead to changes in the diaphragm, which along with ascites may impair daily activities and result in global motor disability and physical inactivity of patients on the waiting list for liver transplantation. OBJECTIVES: This study sought to delineate the profile of candidates for liver transplantation while on the waiting list at the Clinical Hospital of State University Campinas (UNICAMP), and to assess and verify whether there is a correlation between functional status of the individuals tested using the 6-minute walk test (6MWT), pulmonary function test (PFT), and respiratory muscle strength with end-stage liver disease candidates for liver transplantation. METHODS: This study was carried out in the Liver Transplantation Unit of the State University of Campinas (UNICAMP). We included 46 patients with end-stage liver disease who underwent the following evaluations: medical history, 6MWT, PFT, maximal inspiratory pressure (MIP), and maximal expiratory pressure (MEP), and SF-36. RESULTS: Correlations were found between the respiratory variables 6MWT and PFT. The walked distance was correlated with MIP and MEP. There was no correlation between the 6MWT and the variables body mass index and age. CONCLUSION: Candidates for liver transplantation have decreased muscle strength, normal lung function, and impaired quality of life, mainly due to physical limitations. Functional status may be correlated with the respiratory assessment (muscle strength and pulmonary function test) in liver disease candidates for transplantation.

Surface electromyography for respiratory assessment of liver transplant candidates, healthy subjects and after chevron post-operative incision.

BACKGROUND: Surface electromyography is a noninvasive technique for detecting the activity of skeletal muscles and especially the muscles for respiratory compliance; namely, the diaphragm and rectus abdominis. This study compares these muscles in healthy individuals, liver disease patients, and after abdominal surgery. OBJECTIVE: To study muscle activity by surface electromyography of the right diaphragm muscles and right rectus abdominis (root means square, RMS), and the manovacuometry muscle strength (maximal inspiratory pressure, MIP; and maximal expiratory pressure, MEP). RESULTS: We evaluated 246 subjects who were divided into 3 groups: healthy (65), liver disease (171), and post-surgery (10). In liver disease group the BMI was higher significantly for ascites (P = .001), and was increase in RMS rectum (P = .0001), RMS diaphragm (P = .030), and a decreased inspiratory and expiratory indices (P = .0001) pressure in the post-surgery group. A multivariate analysis showed tendency to an increased BMI in liver disease and in the post-surgery groups correlated with an increased RMS rectum and the lower MIP/MEP (P = .11). The receiver operating characteristic curve showed that RMS rectus was capable of discriminating liver disease and post-surgery patients from healthy subjects (area = 0.63; 95% CI 0.549-0.725). CONCLUSION: The muscle activity of normal individuals is lower than in subjects with deficit muscles because less effort is necessary to overcome the same resistance, observed by surface electromyography and muscle strength.

Validation of 20-meter corridor for the 6-minute walk test in men on liver transplantation waiting list.

BACKGROUND: Guidelines established by the American Thoracic Society recommend the use of corridors 30 m in length for the 6-minute walk test (6MWT). However, not all institutions have such long corridors, which hinders or prevents 6MWT performance and use of its benefits. OBJECTIVE: To compare the distances walked by male patients with cirrhosis on the liver transplantation waiting list, we performed 6MWT on corridors 20 and 30 m long. METHODS: This prospective study included 10 patients on the waiting list for liver transplantation. They underwent 2 walk tests: the first test in a 20 m corridor and the second in a 30 m corridor. We assessed physiologic variables (heart rate, oxygen saturation, arterial blood pressure) and the subjective sensation of dyspnea at rest at 6 and 9 minutes after each walk. Statistical analysis was performed using the Wilcoxon test. RESULTS: Data are expressed as mean ± sd. Patient age was 59 ± 10 years. The distances walked by the patients were shorter than those predicted for their age and gender (586 ± 45 m) in both tests, no significant difference was observed between the first and the second 6MWT (437 ± 101 m vs 465 ± 80 m; P=.131) or among the physiologic variables. CONCLUSION: We concluded that a 20 m corridor can be used safely and effectively as an alternative to 30 m for the 6MWT for male patients with cirrhosis on the liver transplantation waiting list.