Enoxaparin is a low-molecular-weight heparin used for prophylaxis against d
eep venous thrombosis. Indications include hip and knee replacement surgery
, risk of deep venous thrombosis during abdominal surgery, and prevention o
f ischemic complications of unstable angina and non-Q-wave myocardial infar
ction. Its efficacy in the prevention of the above complications has been p
reviously studied; however, the liberal use of enoxaparin is not without in
cident. Complications of enoxaparin include hemorrhage, thrombocytopenia, a
nd local reactions. Since 1993 there have been more than 40 reports of epid
ural or spinal hematoma formation with the concurrent use of enoxaparin and
spinal/epidural anesthesia or spinal puncture. Herein reported are two cas
es of abdominal wall hematomas in patients receiving prophylaxis with enoxa
parin. Both patients sustained an unexplained fall in the hematocrit and ab
dominal pain. A CT scan confirmed the diagnosis. One patient recovered unev
entfully; however, the other patient, on chronic hemodialysis, became hemod
ynamically unstable and hyperkalemic and sustained a fatal cardiac arrhythm
ia. An extensive review of the literature revealed no similar eases of abdo
minal wall hematomas associated with enoxaparin although other complication
s, including spinal and epidural hematomas, psoas hematomas, and skin necro
sis have been reported. The extended use of enoxaparin as an anticoagulant
requires the physician to be vigilant of these rare complications. Bleeding
can occur at any site during therapy with enoxaparin. An unexplained fall
in the hematocrit or blood pressure should lead to a search for a bleeding
site.