Venous thromboembolism: prophylaxis: pneumatic compression stockings reduced PE in heart surgery.

Clinical bottom line (level 1b)

  1. Patients who had open heart surgery and given heparin plus pneumatic compression stockings, were less likely to have a symptomatic post-operative pulmonary embolism than those given heparin alone (NNT = 39 at 30 days) .
Ramos et al: Chest 1996; 109: 82-85
Expires May 2003

The study

Unblinded concealed randomised trial without intention-to-treat
Setting: cardiothoracic unit, USA

2554 patients (aged mean 64 years, 70% male) having open heart surgery

Excluded if
  • known deep vein thrombosis before surgery
  • bleeding complication
  • intraoperative death
  • intolerant to pneumatic compression stockings
  • prophylaxis withdrawal before fully ambulating


    • Control Group: (n = 1196, 1196 analysed): heparin 5000 units subcutaneously twice daily for five days
    Experimental Group: (n = 1355, 1355 analysed): heparin 5000 units subcutaneously twice daily and sequential pneumatic compression stockings (from ankle to proximal thigh) for five days. Stockings were removed when patient went walking

    100% followed for 30 days
    Outcome notes:
    • symptomatic pulmonary embolism : diagnosed by high probability v/q scan or positive pulmonary angiogram if indeterminate.

    The evidence

    Outcome Time to outcome CEREERRRR
    (95% CI)    		ARR
    (95% CI)    		NNT
    (95% CI)
    symptomatic pulmonary embolism 30 days 48
    (4.0%)    		 20
    (1.5%)    		 63%
    (38% to 78%)    		 2.54%
    (1.25% to 3.82%)    		 39
    (26 to 80)

    Comments

    1. Does exclusion of patients 'intolerant of pneumatic compression stockings' bias results?
    2. Do pneumatic stockings need to be worn for five days, or would during the operation alone suffice?

    Citation

    1. Ramos R, Salem BI, De Pawlikowski MP, et al: The efficacy of pneumatic compression stockings in the prevention of pulmonary embolism after cardiac surgery. Chest 1996; 109: 82-85
    Contributor: Chris Ball and Clare Wotton, May 2000
    Reviewer:

    Clinical Question.
    Patient open heart surgery
    Intervention or Exposure heparin and compression stockings
    Comparison heparin alone
    Outcome symptomatic pulmonary embolism