Description of Event or Problem · 1
BIOMEDICAL ENGINEERING RECEIVED A PHONE CALL AT 4:30 AM FROM MICU ON JULY 29, 2005 STATING THAT THE TELEMETRY SYSTEM WAS DROPPING PATIENT CARDIAC SIGNALS ON A RANDOM BASIS. THE AMOUNT OF SIGNALS BEING DROPPED VARIED FROM A FEW TO MAYBE EIGHT OR MORE. BIOMEDICAL ENGINEERING RESPONDED AND PLACED A SERVICE CALL TO PHILIPS. PHILIPS FIELD SERVICE ARRIVED AT THE HOSPITAL AT 11:45 PM THE SAME DAY. PHILIPS AND BIOMEDICAL ENGINEERING TRIED TO FIND THE CAUSE OF THE PROBLEM AND CONCLUDED THAT AN INTERFERENCE SIGNAL WAS COMING INTO THE SYSTEM FROM AN UNKNOWN SOURCE AND THAT A SPECTRUM ANALYZER WAS NEEDED FOR FURTHER DIAGNOSIS. AT SOME TIME ON JULY 30, 2005 THE INTERFERENCE PROBLEM WENT AWAY AND THE SYSTEM OPERATED NORMALLY. ON AUGUST 10, 2005 PHILIPS RETURNED AND TRIED TO DUPLICATE THE PROBLEM BUT WITH NO SUCCESS. AT 9:00 PM THE SAME DAY THE PROBLEM RETURNED. PHILIPS CAME IN ON AUGUST 11, 2005 BUT WAS UNABLE TO LOCATE THE PROBLEM. THEY RETURNED THE NEXT DAY WITH A SYSTEM SPECIALIST AND A SPECTRUM ANALYZER. THEY DETERMINED TO RELOCATE THE FREQUENCY RANGE OF THE UPPER TRANSMITTERS TO CORRECT ANY INTERFERENCE PROBLEMS OCCURRING AT THE 612 MHZ BAND. AT 2:30 AM ON AUGUST 13, 2005 THE PROBLEM RETURNED. BIOMEDICAL ENGINEERING AT 8:00 AM ARRIVED AT THE HOSPITAL AND PHILIPS FIELD SERVICE ARRIVED AROUND 2:00PM. FROM THIS POINT ON AN EXTENSIVE TROUBLE SHOOTING EFFORT WAS PUT INTO EFFECT WITH BOTH BIOMEDICAL ENGINEERING AND PHILIPS. BIOMEDICAL ENGINEERING MONITORED THE PROBLEM AROUND THE CLOCK. SPECTRUM ANALYSIS WAS CONDUCTED WITHIN THE HOSPITAL TO DETERMINE IF THE SOURCE OF INTERFERENCE WAS BEING GENERATED EXTERNALLY AND THEN PICKED UP BY THE TELEMETRY OR IF WAS BEING GENERATED BY THE SYSTEM ITSELF. BECAUSE THE INTERFERENCE WAS VERY INTERMITTENT, A DIAGNOSIS WAS DIFFICULT TO OBTAIN. BIOMEDICAL ENGINEERING AND PHILIPS WORKED TOGETHER AS A TEAM AND BEGAN TO LOOK AT INDIVIDUAL COMPONENTS OF THE SYSTEM TO ISOLATE THE CAUSE. ON AUGUST 17, 2005 IT WAS DECIDED TO CONCENTRATE ON THE TRANSMITTERS. BIOMEDICAL ENGINEERING WAS SUSPICIOUS OF ONE PARTICULAR TRANSMITTER AND ISOLATED IT. AT 3:15 PM THE INTERFERENCE PATTERN RETURNED AND BIOMEDICAL ENGINEERING REMOVED THE BATTERY FROM THE TRANSMITTER. THE INTERFERENCE WENT AWAY IMMEDIATELY. THE BATTERY WAS PLACED BACK INTO THE TRANSMITTER. TEN MINUTES LATER THE INTERFERENCE RETURNED, THE BATTERY WAS REMOVED, AND THE PROBLEM WENT AWAY. THE SOURCE OF THE PROBLEM HAD BEEN FOUND. THE TRANSMITTER WAS GIVEN TO PHILIPS FOR AN ENGINEERING ANALYSIS. A REPORT OF THEIR FINDINGS WILL BE SENT TO BIOMEDICAL ENGINEERING. IT SHOULD BE POINTED OUT THAT FINDING THE PROBLEM WAS MADE VERY DIFFICULT BY THE FACT THE PROBLEM OCCURRED AT RANDOM AND INFREQUENT INTERVALS.