Electrical Stimulation to Improve Blood Flow
After surgery, it is common to have a neuromuscular electrical stimulation (NMES) device or intermittent pneumatic compression (IPC) device to improve blood flow in the legs. The NMES includes electrodes that are stuck over specific motor points to cause muscle contraction. The IPC device typically goes around the lower leg to squeeze the vessels and push the blood back to the heart. The role of both of these is to improve blood flow in the lower extremities and decrease the risk of blood clots. While early ambulation after surgery is becoming standard practice to promote natural pumping of blood back to the heart through muscle contraction, this is not feasible with every surgery. In addition, the patient may be able to walk, but the duration and frequency of physical activity may be limited due to fatigue, side effects of medications, and overall deconditioning.
Bahadori et al performed a study to compare the effects of NMES to IPC and their effect on enhancing microcirculatory blood flow in the thigh (1). A Laser Speckle Contrast Imager was used to measure the superficial blood flow on the leg. They compared three different scenarios: IPC, NMES with a visible muscle contraction, and NMES without a visible muscle contraction. Compared to baseline blood perfusion, the NMES with a visible muscle contraction increased blood flow by 399.8%. The NMES without a visible muscle contraction and IPC elicited 150.6% and 117.3% increase in blood flow respectively. Thus, they concluded that the NMES device was superior to the IPC device. More research is still needed since this was a small sample size and only tested on healthy males. However, we can take this information to propel further research in the use of modalities post-surgery. In the outpatient PT setting, an NMES device may be recommended by your therapist if you are non-weight bearing for a long period of time to promote muscle activation and superficial blood flow in a seated position.
Jill Hoffman PT, DPT is a physical therapist specializing in treating orthopedic conditions.
- Bahadori, Shayan, et al. “The Effect of Calf Neuromuscular Electrical Stimulation and Intermittent Pneumatic Compression on Thigh Microcirculation.” Microvascular Research, vol. 111, 2017, pp. 37–41., https://doi.org/10.1016/j.mvr.2017.01.001.