Summary of MedSun Reports Describing Adverse Events With Arthroscopic Pumps/Tubing
MedSun: Newsletter #31, December 2008

Over the past 2 years, MedSun has received 14 adverse event reports involving arthroscopic pumps/tubing that occurred in the operating room of the hospitals submitting these reports. These reports are associated with five manufacturers: Arthrex Arthroscopy Instruments, Inc. (9), Stryker Endoscopy (2), Smith & Nephew (1), ConMed Linvatec (1) and DePuy Mitek (1). The reports were submitted by 10 hospitals between October 10th, 2006 and October 10th, 2008. The device problems are:

• Pressure Problems/Pressure Alarm Malfunction (7)
• Over Infusion of Fluid (6)
• Failure to Maintain Power (1)


There are no MedSun reports for this device involving a patient death during this time period. There are 7 reports that mention a device malfunction and 1 report that mentions a device failure. There are 9 reports that mention a patient injury, 7 injuries were reported as minor and 2 injuries required prolonged hospitalization. The patient injuries listed below were reported in 9 of the 14 reports.

• Swelling (5)
• Edema (2)
• Compartmental Syndrome (1)
• Fluid Extravasation (1)

There were no MedSun reports for this device involving a patient under the age of 21 during this time period. From the reports that listed patient age (12 reports, 13 patients), the average age was 57 years old with a standard deviation of 14. Of the reports that listed patient gender, 4 reports involved female patients and 10 reports involved male patients.

These MedSun reports contributed to FDA awareness of the device problems. FDA continues to investigate these problems. If you have experienced these types of problems, please report them to FDA.




MedSun Arthroscopic Pump/Tubing Adverse Event Reports received between October 10th, 2006 and October 10th, 2008
Device Device Identifiers Event Description
Arthrex Arthroscopy Instruments, Inc./Continuous Wave II Model #AR-6400 Patient underwent right ankle arthroscopy and calcaneal nonunion excision. Immediately following the procedure, it was found that the patient had right lower extremity compartments with no pulse of dorsalis pedis artery. Arterial doppler confirmed. Immediate fasciotomy of right lower extremity released four compartments of the leg and pulses immediately returned. Patient transferred to main hospital and admitted. Two days later, patient underwent irrigation and debridement and closure of right lower extremity wound. The patient was discharged in good condition.
Stryker Endoscopy Device Identifiers Unknown The nurse reported during the surgeon's first case of the day, a shoulder arthroscopy, it was noted the pump was using an excessive amount of arthroscopy fluid (34 bags total). The pump was recalibrated partway through the case and seemed to work better. For the surgeon's second case of the day, a different pump (but same make/model) was used and the same problems began to occur. The doctor made the decision to continue operation with gravity fluid rather than continue using the pumps due to safety concerns. The first patient had a moderate amount of fluid extravasation to right shoulder and breast, yet not unusual for this type of surgery. It appeared there was no significant or unexpected injury to the patients. However, it does appear the pumps may have issues with maintaining their calibrations. Of note, a previous report, with the same issue/equipment was filed, which required extended hospital stay.
Arthrex Arthroscopy Instruments, Inc./Continuous Wave III Model #AR-6475 During a knee arthroscopy, a malfunction of the equipment resulted in the infusion of the incorrect amount of fluid into the knee and surrounding tissue.
Stryker Endoscopy Device Identifiers Unknown The patient was undergoing rotator cuff repair where the pump was being used to insufflate the shoulder joint. After the procedure, as drape was removed, it was noted that the patient had severe swelling to neck, breast and shoulder. The pump's purpose is to flush extra fluid into joint to aide during the surgical procedure. There is a drain component to the pump which did not work entirely as intended. Some fluid was removed, but clearly a large amount was retained. The surgeon and anesthesiologist were both concerned by the amount of fluid and possible constriction of the airway, so the patient was admitted for observation in the ICU. This was originally an outpatient procedure. Typically about 16-18 liters of NS is pumped into a patient. However, OR staff did not know how much fluid was collected in the drain. They did say that the fluid leaves the field by suction yankauer as well as through the arthroscopy sites so it is difficult to know exactly how much fluid was retained.
Smith and Nephew, Inc./Dyonics 25 Fluid Management System Catalog #7211010 The pump powered off in the middle of a surgical procedure. After trouble shooting, the pump powered up and continued to work properly for the remainder of the procedure. No harm to patient.
Arthrex Arthroscopy Instruments, Inc./Continuous Wave II Model #AR-6400 During a knee arthroscopy, a malfunction of the equipment and product resulted in the infusion of the incorrect amount of fluid into the knee and surrounding tissue. Upon disconnection of the tubing, fluid projected from the tubing as if under high pressure. No pressure alerts were noted from the pump console while in use.
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Arthrex Arthroscopy Instruments, Inc. Lot #002216Arthrex tubing malfunctioned causing excessive amount of fluid into patient's left leg near the incision site. Swelling of the extremity was noted by the staff. The tubing was replaced and the procedure was competed without incident.
Arthrex Arthroscopy Instruments, Inc. Device Identifiers Unknown Arthroscopic incision and drainage of right knee. Orange thigh stabilizer was used and tourniquet pressure set at 300. Arthrex pressure irrigator set at 80 pressure and 100 flow settings per MD. A total of (5) 3L bags of Lactated Ringer’s solution, (1) 3L and (1) 1L bags of bacitracin irrigation were prepared. There was a large quantity of fluid on floor during the surgery. When the case was over and the drapes were removed, edema was noted to right upper thigh, scrotum, penis and lower abdomen. The patient was then sent to the PACU alert and oriented. The Arthrex rep was then paged by the surgeon. The tourniquet and irrigator were checked by the Biomed with all disposables saved.
Arthrex Arthroscopy Instruments, Inc./Continuous Wave II Model #AR 6400, Lot #004435 Due to constant flow, the tubing was replaced with new tubing and there continued to be inadequate pressure and flow for joint distention. Right knee swelling resulted.
ConMed Linvatec Model #87000 The patient underwent a right knee arthroscopy, lateral menisectomy and limited synovectomy for plica procedure. After the procedure, the nurse noted right thigh swelling. During the surgery, the arthroscopic pump (ConMed) kept alarming unless the start button was pushed continuously by someone. The button was pushed for approximately 40-50 seconds at the beginning of surgery. Since it was not efficient, the pump tubing was changed. Three nurses and two OR techs attempted to troubleshoot the problem and the tubing was still not working. The surgeon decided to use gravity tubing to complete the surgery instead of the arthroscopic pump. The surgeon also stated that he had problems using this kind of pump in the past, however, there have been no other reports of problems at this facility.
DePuy Mitek/FMS Duo Device Identifiers Unknown During arthroscopic knee surgery, the irrigation pressure had been set to 50. During the case, it was noticed that the pump display was reading 100. The irrigation pump did not alarm.The irrigation pump was removed from service following the incident and the tubing from the case was saved. The manufacturer states that the pump will alarm between 10 and 140. These are hard limits and cannot be changed. However, the pump display does not note the units of measure. The display is in ft H2O, but without the decimal point. For example, if the pump displays "50", it has been set at 5.0 ft H2O. The accuracy of the pump display was confirmed using a digital manometer and a 60cc syringe to pressurize the tubing. Pressure was then measured on the digital manometer in cm H2O and then converted to ft H2O. Several measurements were taken to verify the accuracy of the display. It was noted that the pump did alarm for high pressure above 140 (14.0 ft H2O). If the alarm condition is met, the pump motor shuts off and stops fluid delivery, and a red LED lights up to indicate high pressure. There is no audible alarm. In this incident, the tubing leading out of the pressure chamber and leading to the pressure transducer input was filled with water, even passed the water filter. According to the manufacturer, the pressure chamber should only be filled about 1/3 of the way full with fluid. The pressure transducer needs to measure air pressure and excess fluid in the transducer tubing can cause erroneous readings and damage to the transducer.The pump was run using a new tubing set and it operated normally. It was noted that the pump would continue to fill the pressure chamber with water if the clamp below the pressure chamber was left open, or if the connection to the pressure transducer was not secure. The pump will continue to fill the pressure chamber with fluid until the desired pressure is reached.
Arthrex Arthroscopy Instruments, Inc./Continuous Wave III Model #AR-6475 During a right knee arthroscopy, the Arthrex pump began alarming "Pressure Fault". The circulating nurse stopped the pump and began looking at the troubleshooting procedure. The nurse looked at the fluid, and it was adequate; she then took the suction tubing from the canister off, and tried to restart the pump. The pump spun very fast and again stated "Pressure Fault". The nurse then reconnected the suction as fluid was coming out of the knee from the field. All the clamps along the tubing were checked, and all were found to be open. The pump was restarted, and again it was spinning really fast, so the pump was stopped again. At this point, the surgeon stated that the patient's thigh was very hard and he was having difficulty bending the knee. The scope was removed from the knee and the tourniquet was released after only 24 min of being inflated. The surgeon then applied pressure to try to reduce the swelling. The nurse continued to troubleshoot the pump by requesting a new Arthrex pump. The tubing was changed over to the new machine and restarted. After one minute the same "Pressure Fault" error occurred, however, this time the scope was not in the knee. The tubing was changed on the new pump, and the pump was restarted. Everything seemed to check out and work correctly, and the case was completed. Unfortunately, the original tubing used was discarded after the case was finished. This is at least the third time a problem of this nature has happened at our facility. This system requires that the exact setup steps be followed precisely in the correct order for the pump to function properly. If the balloon inside the cylinder is inadvertently collapsed, pressure changes will not be correctly detected. The balloon may become collapsed by leaving the tubing clamps on when starting the pump, or by spiking the fluid bags before inserting the disposable pressure sensing components. The pressure calibration problem will not be resolved if the tubing is disconnected and reconnected or if the same tubing is used on a different machine.
Arthrex Arthroscopy Instruments, Inc./Continuous Wave III Model #AR-6475 The arthroscopic pump was set at 45 mmHg per doctor's request. The pump appeared to be functioning correctly. However, at end of case, MD noticed patient's left leg was tight and had a slight edema. RN called Technical Services to look at the pump and noticed the bladder on the tubing pressure sensing component was flattened. RN and the technician switched pumps and tubing altogether. The patient was then sent to the recovery room after surgery for monitoring of left leg. There have been three reports of problems with this device reported to Clinical Engineering. Post event, the device functioned properly and all are most likely related to the tubing used with this device. After an internal analysis, the problem can be replicated in the following way: (Note that this is not the ONLY way). When the tubing set comes from the factory, there is a clamp at the sterile patient end. There is also a cap over the pressure sensing portion, which depresses the piston plunger on the pressure sensing component, opening the lumen of the balloon to the environment. The bags are then spiked and hung. After the bags are hung, the hydrostatic pressure from hanging fluid causes the balloon to collapse easily since the lumen is open to the environment. The cap on the pressure sensor is then removed, and the pressure sensor is plugged into the pump. Because the balloon has low air volume in it, it can easily collapse if it has not already. A pressure sensor with a collapsed balloon is useless. Now, if the company's instructions are followed verbatim by plugging the pressure sensor in FIRST, this problem will likely be avoided. However, there is no force function to require the user to follow the proper steps.
Arthrex Arthroscopy Instruments, Inc./Continuous Wave III Model #AR-6475 At case start after hooking up pump and hooking up camera, light source, shaver and suction, liquid filled the shoulder. The pump was turned off, taken out of service and sent to the Biomedical Department. The tubing was then changed out. The pump was cycling at a high rate of speed. Biomed completely checked out the pump. The operation was normal; pressure sensor operating normally. A possible problem with the disposable tubing was noted. There have been three reports of problems with this device reported to Clinical Engineering. Post event, the device functioned properly and all are most likely related to the tubing used with this device. After an internal analysis, the problem can be replicated in the following way: (Note that this is not the ONLY way). When the tubing set comes from the factory, there is a clamp at the sterile patient end. There is also a cap over the pressure sensing portion, which depresses the piston plunger on the pressure sensing component, opening the lumen of the balloon to the environment. The bags are then spiked and hung. After the bags are hung, the hydrostatic pressure from hanging fluid causes the balloon to collapse easily since the lumen is open to the environment. The cap on the pressure sensor is then removed, and the pressure sensor is plugged into the pump. Because the balloon has low air volume in it, it can easily collapse if it has not already. A pressure sensor with a collapsed balloon is useless. Now, if the company's instructions are followed verbatim by plugging the pressure sensor in FIRST, this problem will likely be avoided. However, there is no force function to require the user to follow the proper steps.


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