Archives of Physical Medicine and Rehabilitation journal homepage: www.archives-pmr.org Archives of Physical Medicine and Rehabilitation 2015;96:63-8
ORIGINAL ARTICLE
Feasibility of Neuromuscular Electrical Stimulation Immediately After Cardiovascular Surgery Kotaro Iwatsu, PT, MSc,a Sumio Yamada, PT, PhD,b Yuki Iida, PT, MSc,a,c Hideyuki Sampei, PT, MSc,a Kiyonori Kobayashi, PT, MSc,d Motoshi Kainuma, MD, PhD,e Akihiko Usui, MD, PhDf From the aProgram in Physical and Occupational Therapy and the bDepartment of Rehabilitation Science, Nagoya University Graduate School of Medicine, Nagoya; cDepartment of Physiotherapy, Kainan Hospital, Aichi; dDepartment of Rehabilitation and the eSurgical Intensive Care Division, Nagoya University Hospital, Nagoya; and the fDepartment of Cardiac Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Abstract Objective: To determine the safety and feasibility of neuromuscular electrical stimulation (NMES) from postoperative days (PODs) 1 to 5 after cardiovascular surgery. Design: Pre-post interventional study. Setting: Surgical intensive care unit and thoracic surgical ward of a university hospital. Participants: Consecutive patients (NZ144) who underwent cardiovascular surgery were included. Patients with peripheral arterial disease, psychiatric disease, neuromuscular disease, and dementia were excluded. Patients with severe chronic renal failure and those who required prolonged mechanical ventilation after surgery were also excluded because of the possibility of affecting the outcome of a future controlled study. Interventions: NMES to the lower extremities was implemented from PODs 1 to 5. Main Outcome Measures: Feasibility outcomes included compliance, the number of the patients who had changes in systolic blood pressure (BP) >20mmHg or an increase in heart rate >20 beats/min during NMES, and the incidence of temporary pacemaker malfunction or postoperative cardiac arrhythmias. Results: Sixty-eight of 105 eligible patients participated in this study. Sixty-one (89.7%) of them completed NMES sessions. We found no patients who had excessive changes in systolic blood pressure, increased heart rate, or pacemaker malfunction during NMES. Incidence of atrial fibrillation during the study period was 26.9% (7/26) for coronary artery bypass surgery, 18.2% (4/22) for valvular surgery, and 20.0% (4/20) for combined or aortic surgery. No sustained ventricular arrhythmia or ventricular fibrillation was observed. Conclusions: The results of this study demonstrate that NMES can be safely implemented even in patients immediately after cardiovascular surgery. Archives of Physical Medicine and Rehabilitation 2015;96:63-8 ª 2015 by the American Congress of Rehabilitation Medicine
After cardiovascular surgery, muscle protein is wasted because of accelerated protein catabolism.1,2 Physical inactivity or immobilization resulting from surgery also stimulates muscle wasting by slowing of protein synthesis, accelerated protein degradation, and apoptosis of myonuclei within muscle fibers.3,4 Since loss of muscle protein in patients after cardiovascular surgery leads to
Supported by the Japanese Society for the Promotion of Science (grant no. 22300186). Disclosures: none.
reduced muscle strength and functional decline, preservation of skeletal muscle protein is a major clinical issue in rehabilitation after cardiovascular surgery. Early mobilization has been widely recognized as a countermeasure against postoperative muscle wasting, since promoting muscle activity has an anabolic effect on muscle protein.6 Despite early mobilization, however, muscle proteolysis remarkably accelerates within 48 hours after cardiovascular surgery, and significant muscle weakness was observed.5 These findings suggest the need for interventions to supplement
0003-9993/14/$36 - see front matter ª 2015 by the American Congress of Rehabilitation Medicine http://dx.doi.org/10.1016/j.apmr.2014.08.012
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early mobilization therapy for preventing postoperative muscle wasting. Neuromuscular electrical stimulation (NMES), which can induce sufficient muscle contractions without a patient’s volitional effort, may be an intervention that can be used in addition to mobility therapy for preventing postoperative muscle wasting. NMES has been reported to reduce muscle protein degradation in patients after abdominal surgery7,8 and to preserve the muscle mass of critically ill patients.9 A number of publications also reported improved functional outcomes with NMES use without adverse events in clinically stable patients with chronic heart failure.10-12 However, there are no clinical data regarding the safety or feasibility of NMES in patients immediately after cardiovascular surgery, in which patients usually require inotropic or vasopressor support to maintain their hemodynamic stability. Therefore, the safety and feasibility of NMES immediately after cardiovascular surgery should be examined in detail by a specifically designed observational study. The aim of this study was therefore to examine the feasibility of NMES in patients immediately after cardiovascular surgery, with a particular focus on patients’ acceptance, the impact on hemodynamic status, and cardiac complications.
Methods Participants Adult patients who were to undergo elective major cardiovascular surgery (coronary artery bypass surgery, valvular surgery, aortic surgery, or combined surgery) at Nagoya University Hospital were consecutively included. Exclusion criteria were severe chronic renal failure (estimated glomerular filtration rate
ORIGINAL ARTICLE
Feasibility of Neuromuscular Electrical Stimulation Immediately After Cardiovascular Surgery Kotaro Iwatsu, PT, MSc,a Sumio Yamada, PT, PhD,b Yuki Iida, PT, MSc,a,c Hideyuki Sampei, PT, MSc,a Kiyonori Kobayashi, PT, MSc,d Motoshi Kainuma, MD, PhD,e Akihiko Usui, MD, PhDf From the aProgram in Physical and Occupational Therapy and the bDepartment of Rehabilitation Science, Nagoya University Graduate School of Medicine, Nagoya; cDepartment of Physiotherapy, Kainan Hospital, Aichi; dDepartment of Rehabilitation and the eSurgical Intensive Care Division, Nagoya University Hospital, Nagoya; and the fDepartment of Cardiac Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Abstract Objective: To determine the safety and feasibility of neuromuscular electrical stimulation (NMES) from postoperative days (PODs) 1 to 5 after cardiovascular surgery. Design: Pre-post interventional study. Setting: Surgical intensive care unit and thoracic surgical ward of a university hospital. Participants: Consecutive patients (NZ144) who underwent cardiovascular surgery were included. Patients with peripheral arterial disease, psychiatric disease, neuromuscular disease, and dementia were excluded. Patients with severe chronic renal failure and those who required prolonged mechanical ventilation after surgery were also excluded because of the possibility of affecting the outcome of a future controlled study. Interventions: NMES to the lower extremities was implemented from PODs 1 to 5. Main Outcome Measures: Feasibility outcomes included compliance, the number of the patients who had changes in systolic blood pressure (BP) >20mmHg or an increase in heart rate >20 beats/min during NMES, and the incidence of temporary pacemaker malfunction or postoperative cardiac arrhythmias. Results: Sixty-eight of 105 eligible patients participated in this study. Sixty-one (89.7%) of them completed NMES sessions. We found no patients who had excessive changes in systolic blood pressure, increased heart rate, or pacemaker malfunction during NMES. Incidence of atrial fibrillation during the study period was 26.9% (7/26) for coronary artery bypass surgery, 18.2% (4/22) for valvular surgery, and 20.0% (4/20) for combined or aortic surgery. No sustained ventricular arrhythmia or ventricular fibrillation was observed. Conclusions: The results of this study demonstrate that NMES can be safely implemented even in patients immediately after cardiovascular surgery. Archives of Physical Medicine and Rehabilitation 2015;96:63-8 ª 2015 by the American Congress of Rehabilitation Medicine
After cardiovascular surgery, muscle protein is wasted because of accelerated protein catabolism.1,2 Physical inactivity or immobilization resulting from surgery also stimulates muscle wasting by slowing of protein synthesis, accelerated protein degradation, and apoptosis of myonuclei within muscle fibers.3,4 Since loss of muscle protein in patients after cardiovascular surgery leads to
Supported by the Japanese Society for the Promotion of Science (grant no. 22300186). Disclosures: none.
reduced muscle strength and functional decline, preservation of skeletal muscle protein is a major clinical issue in rehabilitation after cardiovascular surgery. Early mobilization has been widely recognized as a countermeasure against postoperative muscle wasting, since promoting muscle activity has an anabolic effect on muscle protein.6 Despite early mobilization, however, muscle proteolysis remarkably accelerates within 48 hours after cardiovascular surgery, and significant muscle weakness was observed.5 These findings suggest the need for interventions to supplement
0003-9993/14/$36 - see front matter ª 2015 by the American Congress of Rehabilitation Medicine http://dx.doi.org/10.1016/j.apmr.2014.08.012
64
K. Iwatsu et al
early mobilization therapy for preventing postoperative muscle wasting. Neuromuscular electrical stimulation (NMES), which can induce sufficient muscle contractions without a patient’s volitional effort, may be an intervention that can be used in addition to mobility therapy for preventing postoperative muscle wasting. NMES has been reported to reduce muscle protein degradation in patients after abdominal surgery7,8 and to preserve the muscle mass of critically ill patients.9 A number of publications also reported improved functional outcomes with NMES use without adverse events in clinically stable patients with chronic heart failure.10-12 However, there are no clinical data regarding the safety or feasibility of NMES in patients immediately after cardiovascular surgery, in which patients usually require inotropic or vasopressor support to maintain their hemodynamic stability. Therefore, the safety and feasibility of NMES immediately after cardiovascular surgery should be examined in detail by a specifically designed observational study. The aim of this study was therefore to examine the feasibility of NMES in patients immediately after cardiovascular surgery, with a particular focus on patients’ acceptance, the impact on hemodynamic status, and cardiac complications.
Methods Participants Adult patients who were to undergo elective major cardiovascular surgery (coronary artery bypass surgery, valvular surgery, aortic surgery, or combined surgery) at Nagoya University Hospital were consecutively included. Exclusion criteria were severe chronic renal failure (estimated glomerular filtration rate
