We hypothesised that adjuvant intermittent pneumatic
compression (IPC) beneath a plaster cast would reduce the risk of
deep-vein thrombosis (DVT) during post-operative immobilisation
of the lower limb. Of 87 patients with acute tendo Achillis (TA)
rupture, 26 were prospectively randomised post-operatively after
open TA repair. The treatment group (n = 14) received two weeks of
IPC of the foot for at least six hours daily under a plaster cast.
The control group (n = 12) had no additional treatment. At two weeks
post-operatively all patients received an orthosis until follow-up
at six weeks. At two and six weeks the incidence of DVT was assessed
using colour duplex sonography by two ultrasonographers blinded
to the treatment. Two patients withdrew from the study due to inability
to tolerate IPC treatment. An interim analysis demonstrated a high incidence of DVT in both
the IPC group (9 of 12, 75%) and the controls (6 of 12, 50%) (p
= 0.18). No significant differences in incidence were detected at
two (p = 0.33) or six weeks (p = 0.08) post-operatively. Malfunction
of the IPC leading to a second plaster cast was found to correlate
with an increased DVT risk at two weeks (φ = 0.71; p = 0.019), leading
to a premature abandonment of the study. We cannot recommend adjuvant treatment with foot IPC under a
plaster cast for outpatient DVT prevention during post-operative
immobilisation, owing to a high incidence of DVT related to malfunctioning
of this type of IPC application. Cite this article:
Deep vein thrombosis is a common complication
of immobilising the lower limb after surgery. We hypothesised that
intermittent pneumatic compression (IPC) therapy in outpatients
who had undergone surgical repair of acute ruptures of the Achilles
tendon could reduce the incidence of this problem. A total of 150 patients who had undergone surgical repair of
the Achilles tendon were randomised to either treatment with IPC
for six hours per day (n = 74) under an orthosis or treatment as
usual (n = 74) in a plaster cast without IPC. At two weeks post-operatively,
the incidence of deep vein thrombosis was assessed using blinded, double-reported
compression duplex ultrasound. At this point, IPC was discontinued
and all patients were immobilised in an orthosis for a further four
weeks. At six weeks post-operatively, a second compression duplex ultrasound
scan was performed. At two weeks, the incidence of deep vein thrombosis was 21% in
the treated group and 37% in the control group (p = 0.042). Age
over 39 years was found to be a strong risk factor for deep vein
thrombosis (odds ratio (OR) = 4.84, 95% confidence interval (CI)
2.14 to 10.96). Treatment with IPC, corrected for age differences
between groups, reduced the risk of deep vein thrombosis at the
two-week point (OR = 2.60; 95% CI 1.15 to 5.91; p =0.022). At six weeks,
the incidence of deep vein thrombosis was 52% in the treated group
and 48% in the control group (OR 0.94, 95% CI 0.49 to 1.83). IPC
appears to be an effective method of reducing the risk of deep vein
thrombosis in the early stages of post-operative immobilisation
of outpatients. Further research is necessary to elucidate whether
it can confer similar benefits over longer periods of immobilisation
and in a more heterogeneous group of patients. Cite this article: