Haemorrhagic shock induced by subcutaneous insulin injection.

Sir—A number of chronic kidney disease patients with diabetes receive intensive insulin therapy nowadays, and many of them are also treated for several comorbidities. The combination of insulin therapy and other comorbidities could result in an unexpected complication.

Case

A 61-year-old female with type 2 diabetes and rheumatoid arthritis was admitted to our hospital on February 2009 for the curettage of a knee prosthesis infection. Intensive insulin therapy with 32-gauge tip × 6 mm needles was initiated 3 years previously. She was administered warfarin 1.5 mg for atrial fibrillation, and prothrombin time-international normalized ratio was prolonged to 2.0. Other laboratory tests revealed decreased kidney function (serum creatinine, 124 μmol/L; estimated glomerular filtration rate, 26.3 mL/min/1.73 m2) and normal platelet count (220 × 109/L).

One day during her hospital stay, she injected her regular insulin by herself under the surveillance of a nurse in the left lower quadrant of the abdominal wall. Thirty minutes later, a subcutaneous haematoma appeared around the injection site. The haematoma enlarged rapidly despite the strenuous manual pressure performed immediately, and she subsequently developed haemorrhagic shock. Computer tomography detected a massive subcutaneous haematoma (Figure 1). Massive transfusion of 12 units of red blood cells and 12 units of fresh frozen plasma, along with further compression of the abdominal wall, was performed, and her haemodynamics stabilized. Follow-up abdominal angiography, however, did not detect the bleeding artery.

Fig. 1

Abdominal computed tomography shows massive subcutaneous haematoma caused by insulin injection.

Discussion

Subcutaneous haematoma caused by insulin injection is a very rare complication [1-3]. One report described that inappropriate maneuver of insulin injection triggered haemorrhagic shock [2]. Although our case had several risk factors, such as chronic kidney disease, diabetes, rheumatoid arthritis, post-operative state and usage of warfarin, insulin injection was used properly. The fact that haemorrhagic shock occurred in this case is a warning of possible complications of insulin injection in high-risk patients.

Although fine needles are remarkably thin, therefore considerably reducing the risk of haemorrhage [4], lethal subcutaneous haematoma could happen even in a careful clinical setting.

Conflict of interest statement. None declared.