Hip Surgery Complication Rare But Deadly

A new patient safety advisory reports that in rare cases patients undergoing hip replacement surgery experience bone cement implantation syndrome (BCIS).

The Pennsylvania Patient Safety Authority (PSA, Harrisburg, USA) has informed that in five out of six reports of BCIS received by the Patient Safety Reporting System (PA-PSRS), the patient died from cardiac arrest associated with implantation of the new hip prosthesis. Elderly patients with underlying heart disease who must receive surgery for a hip fracture using bone cement were found to be most at risk of developing BCIS. Although cardiac arrest and death are the most severe outcomes associated with BCIS, some warning signs that occur within minutes of using the bone cement include: low blood pressure, fluid in the lungs, increased airway resistance, irregular heartbeat, hypothermia, and increased bleeding. The patient safety advisory was published in December 2006.

BCIS occurs when methylmethacrylate (MMA) cement interdigitates within the interstices of cancellous bone. The exothermic binding reaction leads to cement hardening and expansion against prosthetic components. The resultant intramedullary hypertension can cause embolization of fat, bone marrow, cement, and air into the femoral venous channels. The residual monomer can also cause vasodilatation and a decrease in systemic vascular resistance, thought to be the cause for the transient hypotension often seen with cement insertion. The release of tissue thromboplastin may trigger platelet aggregation, microthrombus formation in the lungs, and cardiovascular instability as a result of the circulation of vasoactive substances.

"While bone cement is associated with BCIS, it is important for orthopedic surgeons to know the syndrome is actually caused by the seal and pressure that develops when the hip prosthesis is inserted after the cement has been placed, not by the cement itself,” said Dr. John Clarke, clinical director of PA-PSRS. "Other materials could also cause the same seal and pressure which leads to the syndrome.”

The PSA advisory article includes several risk reduction strategies including evaluating and monitoring the patient's condition before and during surgery for factors indicating high risk, thoroughly cleaning the shaft of the thigh bone before inserting the prosthesis, and using techniques for inserting the cement that minimize the pressure.



Related Links:
Pennsylvania Patient Safety Authority