More than a hundred years ago, a pathology was started to be described in the critical patient, characterized by the loss of strength and muscle mass. The weakness acquired in the Intensive Care Unit (ICU) is a term that describes diffuse, symmetrical and widespread muscle weakness that develops after the admission to the ICU without other identifiable causes.
Studies have shown that muscle weakness and fitness deconditioning are among 25-100% of patients ventilated for more than 7 days. The published evidence on the effectiveness of early physiotherapy in this area is very limited and the possibilities of instrumental aid should be explored, probably the most commonly used modality in ICU is Neuromuscular Electrical Stimulation (NEMS).
Patient's condition after admission to the ICU
Studies have shown that patients who required admission to the ICU subsequently suffer alterations, decrease in aerobic capacity and detriment of their quality of life, due to the functional dependence they develop.
In unconscious patients, passive movements maintain the range of motion, avoiding joint contractures and modulating muscle tone. In addition, it has been observed an increase in the vascular conductance towards skeletal muscles that are passively mobilized without a concomitant increase in metabolism.
Active exercises are movements within the limits of mobility, without a segment restriction, which is caused by an active contraction of the muscles that cross that joint. These strategies should be associated with the promotion of functional independence in the critical patient, manifested in the possibility of adopting postures, carrying out transfers and even wandering or moving, aspects that together are part of the concept of early mobilization.
While physiotherapeutic intervention uses a variety of non-instrumental maneuvers, the potential for instrumental aid that exists and that it is widely used in non-critical patients should be explored. Probably the most commonly used modality in ICU is Neuromuscular Electrical Stimulation (NEMS).
Electrostimulation for patients after ICU discharge
NEMS, as a tool for prevention and rehabilitation in ICU patients with polyneuropathy should be investigated to include its use in everyday practice, as it is likely to help anticipate deterioration of the muscle structure and function. The same consideration applies to patients who, although they do not have acquired polyneuropathy, are prone to it because of their critical condition.
Electricity has an effect on every cell and tissue it passes through. The type and extent of the response depend on the type of tissue, its characteristics and the nature of the applied current. Physical therapy clinically uses electric currents for the following reasons:
- To create muscle contraction through the nerve or muscle stimulus.
- For ethical sensitive nerves helping to treat pain.
- To create an electric field in biological tissues simulating or altering healing processes.
- To create an electric field on the surface of the skin.
- To drive beneficial ions for healing processes in or through the skin.
Muscle contractions generated by electrostimulation first recruit fibers of larger diameter axons that inert the type II fibers, and the smaller axon fiber is recruited later, contrary to physiological contraction.
NMES to prevent fat loss and muscle strength
NMES has come to occupy a place in the prevention of intensive care unit-acquired weakness early and safely in the form of prevention of muscle mass and strength loss in sedated patients where our greatest intervention is passive mobilization.
How can we use it? Through the i-motion biojacket that has the highest technology in physiotherapy. In cases of patients that cannot use this type of electrodes, i-motion also allows us to use it along with passive or active movements described above. The dosage and parameters that are recommended, according to recent studies of NMES in patients in ICU, are as follows:
- Dosage: 5 days a week, 30 minutes during the first week of intervention. 45 minutes starting from the second week, in order to allow a progressive muscle adaptation.
- Current type: symmetrical biphasic.
- Intensity: The intensity generated by a maximum visible contraction is evaluated. From this value, take 60% and increase it by 10% every 5 minutes.
- Frequency: The first 5 minutes will be warming up with a frequency of 15 Hz in order to improve the oxidative capacity of the muscle, the next 20 minutes (35 minutes from the second week) a frequency of 100 Hz will be used to improve the strength in half the time, the other half a frequency of 50Hz will be used to improve endurance, and the last 5 minutes will be performed at 10 Hz to produce relaxation, increase blood supply and endorphin segregation.
- Pulse duration: 400 μs (31.33–35).
- On and Off times: For the warm-up it is recommended to use 8 seconds of contraction by 3 of relaxation to achieve the aforementioned goals. During the central work, 4 seconds of contraction and 30 seconds of relaxation will be performed, corresponding to a 1:5 ratio.
- Ramps: up and down 1 second.
With the biojacket and the development of professional electric muscle stimulation at imotion.ems.com, recovering strength and muscle mass after a hospital process is no longer a problem.
- Hanekom S, Gosselink R, Dean E, van Aswegen H, Roos R, Ambrosino N, et al. The development of a clinical management algorithm for early physical activity and mobilization of critically ill patients: synthesis of evidence and expert opinion and its translation into practice. Clin Rehabil. 2011 Sep;25(9):771–87.
- Perme C, Chandrashekar R. Early mobility and walking program for patients in intensive care units: creating a standard of care. Am J Crit Care Off Publ Am Assoc Crit-Care Nurses. 2009 May;18(3):212–21.
- Kho, M., Truong, A., Brower, R., Palmer, J., Fan, E., & Zanni, J. et al. (2012). Neuromuscular Electrical Stimulation for Intensive Care Unit-Acquired Weakness: Protocol and Methodological Implications for a Randomized, Sham-Controlled, Phase II Trial. Physical Therapy, 92(12), 1564-1579
- Cameron, M. (2009). Agentes físicos en rehabilitación (3ra ed.). Barcelona: Elsevier España. Cap 8, pag 207- 241