Complications. The complications of tetanus are varied and include pneumonia or other respiratory infections when the patient can’t control their breathing, high blood pressure and an irregular heartbeat. Some patients experience spasms that are so violent that they suffer bone fractures. In severe cases of the disease, the patient can suffer brain damage and slip into a coma. Death is also a possibility with a tetanus infection. In very bad cases of the disease, the death rate is about 50 percent.