A 64 year hypertensive obese female was undergoing surgery for fracture femur under general anaesthesia. Intraoperatively her end tidal CO2 volume decreased to 20 from 40 mmHg followed by hypotension and oxygen saturation of 85%. What could be the most probable cause?
Fat embolism is usually seen after long bone fracture. It becomes more fulminant after reaming of long bones especially femur. The clinical presentation is dyspnea, restlessness, tachycardia, hypotension, mental clouding and persistently falling oxygen saturation, petechial haemorrhages over chest and axilla. End tidal carbon dioxide falls. Finally there may be convulsions, coma and death. X-ray chest shows pulmonary interstitial infiltrates
Treatment includes oxygenation judicious fluid therapy, high dose corticosteroids. Patients not responding to these measure may require IPPV with positive end expiratory pressure (PEEP).