Efficacy of Respiratory Muscle Training in the Immediate Postoperative Period of Cardiac Surgery: A Systematic Review and Meta-Analysis.

INTRODUCTION: This study aimed to evaluate the efficacy of respiratory muscle training during the immediate postoperative period of cardiac surgery on respiratory muscle strength, pulmonary function, functional capacity, and length of hospital stay. METHODS: This is a systematic review and meta-analysis. A comprehensive search on PubMed®, Excerpta Medica Database (or Embase), Cumulative Index of Nursing and Allied Health Literature (or CINAHL), Latin American and Caribbean Health Sciences Literature (or LILACS), Scientific Electronic Library Online (or SciELO), Physiotherapy Evidence Database (or PEDro), and Cochrane Central Register of Controlled Trials databases was performed. A combination of free-text words and indexed terms referring to cardiac surgery, coronary artery bypass grafting, respiratory muscle training, and clinical trials was used. A total of 792 studies were identified; after careful selection, six studies were evaluated. RESULTS: The studies found significant improvement after inspiratory muscle training (IMT) (n = 165, 95% confidence interval [CI] 9.68, 21.99) and expiratory muscle training (EMT) (n = 135, 95% CI 8.59, 27.07) of maximal inspiratory pressure and maximal expiratory pressure, respectively. Also, IMT increased significantly (95% CI 19.59, 349.82, n = 85) the tidal volume. However, no differences were found in the peak expiratory flow, functional capacity, and length of hospital stay after EMT and IMT. CONCLUSION: IMT and EMT demonstrated efficacy in improving respiratory muscle strength during the immediate postoperative period of cardiac surgery. There was no evidence indicating the efficacy of IMT for pulmonary function and length of hospital stay and the efficacy of EMT for functional capacity.

Synergistic effect of cannabidiol and transcutaneous electrical nerve stimulation on neuropathic and inflammatory pain in mice.

OBJECTIVES: Pain is the most common cause of seeking healthcare and the leading cause of disability worldwide. Although cannabidiol and transcutaneous electrical nerve stimulation (TENS) are effective and safe strategies for treating chronic pain, the combined effect of these interventions remains overlooked. To compare the isolated and combined effect of cannabidiol and TENS in the treatment of experimental neuropathic and inflammatory pain. METHODS: Swiss mice were subjected to chronic constriction injury (CCI)-induced neuropathic or carrageenan-induced inflammatory pain models. Cannabidiol or TENS alone and the combination of these therapies were administered once. The nociceptive threshold was measured by the von Frey test. IL-1ß, TNF-α and IL-10 cytokine levels were measured by ELISA from spinal cord samples. RESULTS: Combined, cannabidiol and TENS potentiate antinociception only in neuropathic pain. IL-1ß and TNF-α levels were similarly reduced when TENS or cannabidiol were administered alone or in combination. However, only cannabidiol and TENS combined increased IL-10 levels. CONCLUSIONS: Our findings indicated TENS and cannabidiol combined were effective in potentiating antinociception in a neuropathic pain model, an effect potentially associated with spinal IL-10 upregulation.

Evaluation of respiratory and peripheral muscle training in individuals undergoing myocardial revascularization.

OBJECTIVES: To investigate the effect of peripheral muscle strength training (PMT) and respiratory muscle strength training (RMT) muscle strength training associated with conventional physical therapy on the respiratory muscle strength, functional capacity, and quality of life in the immediate postoperative period of patients undergoing coronary artery bypass graft (CABG). METHODS: This was a randomized controlled trial. Eighty-three patients undergoing CABG were divided into two groups: Intervention group, patients that received PMT and RMT associated with conventional physical therapy, one session a day for 5 days; control group, patients that received conventional physical therapy, one session a day for 5 days. All patients had respiratory muscle strength, peripheral muscle strength, functional capacity, and quality of life evaluated by manovacuometry, dynamometry, 6-min walking test, and 36-item Short-Form Health Survey Questionnaire, respectively, before and 5 days after CABG. RESULTS: Both groups showed a significantly reduced respiratory muscle strength after CABG; however, in the intervention group, the inspiratory muscle strength reduction was lower (confidence interval [CI] 95%: 2.29 [1.9; 27.54]). The quality of live domains for pain (CI 95%: 3.08 [5.21; 24.97]) and vitality perception (CI 95%: 2.51 [2.12; 19.53]) worsened in the control and improved in the intervention group (pain: CI 95%: 1.19 [-3.38; 13.09]; vitality CI 95%: 0.07 [-6.55; 7.04]). Both groups showed reduced functional capacity and expiratory muscle strength after CABG. CONCLUSION: Conventional physical therapy combined with PMT and RMT may reduce inspiratory muscle strength loss and improve pain and vitality perception in the immediate postoperative period after CABG.

Investigation of the Involvement of the Endocannabinoid System in TENS-Induced Antinociception.

Transcutaneous electrical nerve stimulation (TENS) promotes antinociception by activating the descending pain modulation pathway and consequently releasing endogenous analgesic substances. In addition, recent studies have shown that the endocannabinoid system controls pain. Thus, the present study investigated the involvement of the endocannabinoid system in TENS-induced antinociception of cancer pain using a cancer pain model induced by intraplantar (i.pl.) injections of Ehrlich tumor cells in male Swiss mice. Low- and high-frequency TENS was applied for 20 minutes to the mice's paws, and to investigate the involvement of the endocannabinoid system were used the N-(peperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pitazole-3-carboixamide (AM251), a cannabinoid CB1 receptor antagonist and (5Z,8Z,11Z,14Z)-5,8,11,14-eicosatetraenyl-methylester phosphonofluoridic acid (MAFP), an inhibitor of the endocannabinoid metabolizing enzyme fatty acid amide hydrolase, injected by via i.pl., intrathecal (i.t.), and intradorsolateral periaqueductal gray matter (i.dl.PAG). Furthermore, liquid chromatography-tandem mass spectrometry, western blot, and immunofluorescence assays were used to evaluate the endocannabinoid anandamide levels, cannabinoid CB1 receptor protein levels, and cannabinoid CB1 receptor immunoreactivity, respectively. Low- and high-frequency TENS reduced the mechanical allodynia induced by Ehrlich tumor cells and this effect was reversed by AM251 and potentiated by MAFP at the peripheral and central levels. In addition, TENS increased the endocannabinoid anandamide levels and the cannabinoid CB1 receptor protein levels and immunoreactivity in the paw, spinal cord, and dorsolateral periaqueductal gray matter. These results suggest that low- and high-frequency TENS is effective in controlling cancer pain, and the endocannabinoid system is involved in this effect at both the peripheral and central levels. PERSPECTIVE: TENS is a nonpharmacological strategy that may be used to control cancer pain. Identification of a new mechanism involved in its analgesic effect could lead to the development of clinical studies as well as an increase in its application, lessening the need for pharmacological treatments.

Evaluation of exercise and potassium chloride supplementation on blood pressure and nociceptive threshold in hypertensive rats.

Hypertensive subjects present an increased nociceptive threshold, and the lack or delay of pain perception may impede detection of angina and myocardial infarction. Nutritional interventions, like potassium chloride (KCl) diet supplementation, and exercises are common nonpharmacological indications for treating hypertension. Spontaneous hypertensive rats (SHR) and normotensive male Wistar rats were submitted to a combination of exercise and KCl diet supplementation. Exercise reduced the nociceptive threshold in SHR; however, this effect was inhibited by KCl supplementation. Exercise and KCl supplementation did not alter systolic blood pressure. Reduction of the nociceptive threshold by exercise may be important for the detection of angina and myocardial infarction in hypertensive individuals.