Profile of respiratory evaluation through surface electromyography, manovacuometry, and espirometry in candidates on the liver transplant waiting list

Surface electromyography in inspiratory muscles in adults and elderly individuals: A systematic review

INTRODUCTION

Electromyography (EMG) helps to evaluate disorders and pulmonary behavior, as impairments in respiratory muscle function are associated with the development of diseases. There is a wide range of methods and protocols used to record and analyze EMG obtained from respiratory muscles, demonstrating a lack of standardization.

OBJECTIVE

To identify the most common procedures used to record surface EMG (sEMG) of inspiratory muscles in adults and elderly individuals through a systematic review (primary), and to evaluate the quality of the report presented by the studies (secondary).

METHOD

Studies published from January 1995 until June 2018 were searched for in the Web of Science, PubMed, LILACS, EBSCO and Embase databases. Only studies evaluating sEMG of inspiratory muscles were included.

RESULTS

The electronic search retrieved a total of 6697 titles and 92 of them were included. A great variability on the methods applied to both recording and processing/analyzing data was found. Therefore, the synthesis of practical/clinical evidence to support immediate recommendations was impaired. In general, the descriptions presented by the studies are poor.

CONCLUSION

The most common procedures used for sEMG were identified. Methodological studies with objective comparisons were fundamental for improving standardization, given the impossibility of recommendations from this review.

Intensive Care of Pulmonary Complications Following Liver Transplantation

Chronic liver disease has been associated with pulmonary dysfunction both before and after liver transplantation. Post-liver transplantation pulmonary complications can affect both morbidity and mortality often necessitating intensive care during the immediate postoperative period. The major pulmonary complications include pneumonia, pleural effusions, pulmonary edema, and atelectasis. Poor clinical outcomes have been known to be associated with age, severity of liver dysfunction, and preexisting lung disease as well as perioperative events related to fluid balance, particularly transfusion and fluid volumes. Delineating each and every one of these pulmonary complications and their associated risk factors becomes paramount in guiding specific therapeutic strategies.

Model for End-Stage Liver Disease Score Before Hepatic Transplantation and Root Mean Square of the Diaphragmatic Domes Affect Postoperative Extubation Time

INTRODUCTION

The liver transplantation procedure, in addition to its prolonged surgical time, also predisposes to complications such as changes in respiratory mechanics, lung volumes, and gas exchange.

OBJECTIVE

This study aims to verify if clinical factors related to the recipient, namely immediate pretransplant Model for End-Stage Liver Disease (MELD) score, surgical time, and root square metric (RMS) of the diaphragmatic domes, affect the extubation time after liver transplantation.

METHOD

A prospective study, with a sample collected for convenience, gathered age (years), sex (male or female), MELD score immediately prior to transplantation (without the addition of special situation scores), and surgical time and time for extubation (in minutes). The latter were obtained from the physiotherapy team records, and surface electromyography was performed within 30 minutes after elective extubation, by a single researcher, with supplemental oxygen support, maintaining SpO₂ ≥ 95% and following protocol of positioning and acquisition of electromyographic signals based on the study of Oliveira et al (2012).

RESULTS

For the 21 patients studied, the RMS of the left dome showed a moderate-intensity correlation (-0.56) with the time of extubation, and linear multiple regression model the left dome (P = .013) and preoperative MELD score (P = .048) showed significant correlation with extubation time.

CONCLUSION

The preoperative MELD score and the RMS values of the left dome significantly correlate with the time for patient extubation after liver transplantation, showing the effect of previously acquired muscle weakness and preoperative MELD score on postoperative outcome.

Combined respiratory muscle training facilitates expiratory muscle activity in stroke patients

[Purpose] The aim of this study was to investigate the effect of combined respiratory muscle training on expiratory muscle activity in stroke patients. [Subjects and Methods] Twenty-five stroke patients were assigned to either the intervention group (n=12) or the control group (n=13). Both groups participated in a conventional stroke rehabilitation program, while the intervention group also received respiratory muscle training for 20 to 30 minutes a day, 3 times a week, for 8 weeks. Surface electromyographic data were collected from the rectus abdominis, internal oblique, and external oblique on the paretic side. Pulmonary function (forced vital capacity) and cough capacity (peak expiratory flow) also were measured. [Results] Both groups showed a significant increase in muscle activity after the intervention. However, the intervention group also showed significant increases in forced vital capacity and peak expiratory flow. Comparison of the 2 groups revealed that the intervention group had greater improvements in pulmonary function, cough capacity, and muscle activity. [Conclusion] The results of this study suggest that combined respiratory muscle training has positive effects on both respiratory function and expiratory muscle activity in stroke patients.

Diaphragm Muscle Surface Electromyography in Patients Submitted to Liver Transplant and Eligible for Extubation

INTRODUCTION

Liver disease induces many organic and metabolic changes, leading to malnutrition and weight and muscular function loss. Surface electromyography is an easily applicable, noninvasive study, through which the magnitudes of the peaks on the charts depict voluntary muscle activity.

AIM

To evaluate the diaphragmatic surface electromyography of postoperative liver transplantation subjects.

METHODS

Subjects were patients who underwent liver transplantation and extubation in the Clinical Hospital of State University of Campinas. Electromyography data were collected with support pressure of ≤10 cm H₂O, Glasgow Coma Scale = 11, and minimum dosages of vasoactive drugs, and data were collected again 30 minutes after extubation. Signal collection was performed with sEMG System Brazil SAS1000V3 electromyograph and electrode stickers. Statistical analysis was performed using R software.

RESULTS

The average time of surgery was 345.36 ± 125.62 minutes. Time from spontaneous mode until extubation was 417.14 ± 362.97 minutes. The RMS (root mean square) values of the right and left domes in spontaneous mode with minimal ventilation parameters were 26.68 ± 10.92 and 26.55 ± 10.53, respectively, and the RMS values after extubation were 31.93 ± 18.69 to 34.62 ± 13.55, for right and left domes. The last calculated pretransplant Model for End-stage Liver Disease score averaged 19.64 ± 8.41.

CONCLUSION

There were significant differences between the RMS of the diaphragm domes under mechanical ventilation and after extubation, showing lower effectiveness of the diaphragm muscle against resistance, without the aid of positive pressure and the existing overload of the left dome.

Exercise manual for liver disease patients

AIM: To increase inspiratory muscle strength and improve the quality of life of candidates for liver transplantation.

METHODS: Twenty-three candidates for liver transplantation participated in the control group and 14 made up the intervention group. The control group consisted of 18 men and 5 women, body mass index (BMI) 27.3 ± 4.5 kg/m² and Model for End-Stage Liver Disease (MELD) 18.2 ± 6.1. The intervention group consisted of 11 men and 3 women, BMI 28.6 ± 5.4 kg/m² and MELD 18 ± 4.5. The presence or absence of ascites was identified in the first patient evaluation and after three months. We evaluated maximal inspiratory pressure (MIP) and maximal expiratory pressure, spirometry, root mean square (RMS) of diaphragm and rectus abdominis, and the quality of life. The exercises were performed daily by patients at home for three months and were supervised at distance monthly. The manual consisted of diaphragmatic breathing exercises, diaphragmatic isometric exercise, Threshold IMT^®, lifting upper limbs with a bat and strengthening the abdomen.

RESULTS: There was significant difference (P = 0.01) between the first (initial) and the third month (final) MIP in the control group and in the intervention group, but there was no difference (P = 0.45) between the groups. The RMS of the diaphragm was lower (P = 0.001) and the functional capacity was higher (P = 0.006) in the intervention group compared to the control. The general health and mental health domains received higher scores after three months in the control group (P = 0.01) and the intervention group (P = 0.004), but there was no significant difference between them. The comparison between the presence of initial ascites with the presence of ascites was performed after three months in the control group (P = 0.083) and intervention group (P = 0.31). There was no significant difference, in relation to the presence of ascites after three months between groups (P = 0.21). In the intervention group, patients with ascites at the end of the time period had decreased scores on the social aspects SF-36 domain (P = 0.023) compared to those who had no ascites.

CONCLUSION: The proposed exercises provide an increase in the inspiratory muscle strength and improve functional capacity, consequently bettering the quality of life of liver disease patients.

The utility of pulmonary function testing in predicting outcomes following liver transplantation

Although pulmonary function tests (PFTs) are routinely performed in patients during the evaluation period before liver transplantation (LT), their utility in predicting post-LT mortality and morbidity outcomes is not known. The aim of this study was to determine the impact of obstructive and/or restrictive lung disease on post-LT outcomes. We conducted a retrospective analysis of patients who had pre-LT PFTs and underwent a subsequent LT (2007-2013). We used statistical analyses to determine independent associations between PFT parameters and outcomes (graft/patient survival, time on ventilator, and hospital/intensive care unit [ICU] length of stay [LOS]). A total of 415 LT recipients with available PFT data were included: 65% of patients had normal PFTs; 8% had obstructive lung disease; and 27% had restrictive lung disease. There was no difference in patient and graft survival between patients with normal, obstructive, and restrictive lung disease. However, restrictive lung disease was associated with longer post-LT time on ventilator and both ICU and hospital LOS (P < 0.05). More specific PFT parameters (diffusing capacity of the lungs for carbon monoxide, total lung capacity, and residual volume) were all significant predictors of ventilator time and both ICU and hospital LOS (P < 0.05). Although pre-LT PFT parameters may not predict post-LT mortality, restrictive abnormalities correlate with prolonged post-LT ventilation and LOS. Efforts to identify and minimize the impact of restrictive abnormalities on PFTs might improve such outcomes. Liver Transplantation 22 805-811 2016 AASLD.

Relative activity of respiratory muscles during prescribed inspiratory muscle training in healthy people

[Purpose] This study aimed to determine the effects of different intensities of inspiratory muscle training on the relative respiratory muscle activity in healthy adults. [Subjects and Methods] Thirteen healthy male volunteers were instructed to perform inspiratory muscle training (0%, 40%, 60%, and 80% maximal inspiratory pressure) on the basis of their individual intensities. The inspiratory muscle training was performed in random order of intensities. Surface electromyography data were collected from the right-side diaphragm, external intercostal, and sternocleidomastoid, and pulmonary functions (forced expiratory volume in 1 s, forced vital capacity, and their ratio; peak expiratory flow; and maximal inspiratory pressure) were measured. [Results] Comparison of the relative activity of the diaphragm showed significant differences between the 60% and 80% maximal inspiratory pressure intensities and baseline during inspiratory muscle training. Furthermore, significant differences were found in sternocleidomastoid relative activity between the 60% and 80% maximal inspiratory pressure intensities and baseline during inspiratory muscle training. [Conclusion] During inspiratory muscle training in the clinic, the patients were assisted (verbally or through feedback) by therapists to avoid overactivation of their accessory muscles (sternocleidomastoid). This study recommends that inspiratory muscle training be performed at an accurate and appropriate intensity through the practice of proper deep breathing.

Effects of a respiratory physiotherapeutic program in liver transplantation candidates

BACKGROUND

Candidates for liver transplantation may have malnutrition, fatigue, loss of muscle mass and function. The combination of these factors leads to overall physical disability and physical inactivity.

OBJECTIVE

The aim of the study was to evaluate the effects of a respiratory physiotherapeutic program on liver transplantation candidates.

METHOD

Forty-two patients were evaluated by respiratory muscle strength, surface electromyography of the rectus abdominis and diaphragm, and spirometry. We also applied the SF-36. The patients were divided into two groups: 12 randomly assigned to the control group and 5 in the intervention group. The intervention consisted of an explanatory and illustrative manual to be followed at home with diaphragmatic breathing exercises, diaphragmatic isometric exercise, Threshold IMT, lifting the upper limbs with a bat, and strengthening the abdominals.

RESULTS

Significant difference was found between initial forced expiratory flow (FEF)25-75% (P = .042) and final FEF25-75 in the intervention group. The control group had significant difference (P = .036) in the diaphragm RMS between initial time and end time. In conclusion, the control group showed greater electrical activity of the diaphragm after 3 months.

CONCLUSION

The intervention group benefited from the exercise, thus improving the FEF25-75%.

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.