Pneumatic Compression

Fig. 20.1

Inflated upper extremity pneumatic pump

Pump variables include: (1) single or multiple chambers; (2) sequential or nonsequential compression; and (3) gradient or non-gradient options (Table 20.1). Single compartment models were initially used to treat lymphedema. The entire limb receives a constant level of compression as the cuff expands and contracts in a rhythmic fashion. The pressure is delivered both centripetally and centrifugally. There is no sequential distribution or gradient of pressure given to the extremity. When comparing single and multi-compartment pumps, subcutaneously injected radioisotope has a more rapid transit to the inguinal lymph nodes with a multi-cell device [4]. Single chamber intermittent pneumatic compression pumps currently are not recommended for patients because superior machines with multiple cells have been developed [5, 6].

Table 20.1

Pneumatic compression pumps currently available for the treatment of lymphedema

Device	Compartment design	Sequential inflation	Gradient
Presion	Single	No	No
Eureduc	Multiple	Yes	No
Hadomer	Multiple	Yes	No
Huntleigh Flowpress	Multiple	Yes	No
Flexitouch	Multiple	Yes	Yes
KCI JOBST System	Multiple	Yes	Yes
Lymphapress	Multiple	Yes	Yes
NormaTec	Multiple	Yes	Yes
Petite Basic System	Multiple	Yes	Yes
Sequential Circulator	Multiple	Yes	Yes
Ventipress	Multiple	Yes	Yes
Wright Linear Pump	Multiple	Yes	Yes

There are two types of multichamber devices that were developed in the 1970s. One pump sequentially inflates up to four individual cells beginning distally and moving proximally. Once all chambers are inflated for a set time, the cuff deflates. This creates a wave of compression that ascends the limb. The other type of pump delivers a gradient of pressure with higher force in the distal chambers and lower pressure in the proximal ones. Unlike the 4-chamber device, this pump may have up to 36 small individual cells with at least three separate zones of compression [5]. The primary difference between each type of system is the amount of pressure delivered to the diseased limb, the pattern of delivery, and the total time of compression. Timed cycles range from a few seconds to several minutes.

Pressure of Compression

There is a large array of settings for intermittent pneumatic compression pumps. The pressure of lymphatic vessels in normal skin ranges from 4 to 8 mmHg, while patients with lymphedema have measurements between 15 and 18 mmHg in the absence of fibrosis [7, 8]. The therapeutic compression must be sufficient to overcome the resistive forces present within diseased tissue, but not so high that it collapses the superficial lymphatics. Muscle contraction normally is required to aid in lymph returning to the heart because of the extremely low pressures in the lymphatics. Intermittent pneumatic compression devices recapitulate the pumping action of muscles.

In addition to possibly collapsing lymphatic vessels, sustained elevated force for a prolonged time period also can lead to ischemic skin damage. Pressures >60 mmHg for an extended time can reduce blood flow [9, 10]. Several studies recommend a peak inflation pressure range of 25–60 mmHg [11–13]. A few authors have demonstrated volume reduction with higher pressures (110–150 mmHg) [14–16].

Time and Frequency of Compression

Unlike manual lymphatic drainage that requires the assistance of a physical therapist, intermittent pneumatic compression therapy can be performed at the convenience of the patient in his/her home. Scientific evidence for the appropriate amount of time and frequency of treatment is sparse. Therapy may range from 30 minutes to 8 hours depending on the device and condition of the patient. One study evaluated self-reported data from patients who were asked to use their pump 2 hours per day for a month, then 1 hour per day thereafter [17]. More than half of individuals surveyed used the pump for the recommended duration; approximately 10 % did not attempt pneumatic compression therapy at all. Patients who followed the prescribed protocol reported a higher satisfaction [17]. We recommend that an individual pump for 2 hours per day at his/her convenience.