aquadex FlexFlow Users Guide

Contents Chapter 1.

Introduction 1.1 Indications for Use 1.2 Contraindication 1.3 Theory of Operation 1.4 Warnings and Cautions 1.5 Technical Description 1.5.1 Modes of Operation 1.5.2 Data Key 1.5.3 Keys, Indicators, and Screen 1.5.4 Features and Protective Systems 1.5.4.1 Pressure Monitoring 1.5.4.2 Compensation of Effects of Height on Pressure 1.5.4.3 Air Detector 1.5.4.4 Blood Leak Detector 1.5.4.5 Ultrafiltration Control 1.5.4.6 Blood Pump Monitoring 1.6 Symbols and Certification

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Chapter 2.

Setup 2.1 Unpacking and Inspection 2.2 Connecting to AC Power 2.3 Loading the Blood Circuit 2.4 Priming the Blood Circuit 2.5 Priming AccessPort(s)

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Treatment 3.1 Starting Therapy 3.1.1 Anticoagulation 3.1.2 Connecting the Withdrawal Catheter 3.1.3 Filling the Blood Circuit 3.1.4 Connecting the Infusion Catheter 3.1.5 Starting Ultrafiltration 3.1.6 Using the Circuit AccessPort(s) 3.2 Emptying the Ultrafiltrate Bag

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Chapter 3.

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Using the MENU Key Using the HELP Key Terminating Treatment Turning the System Off Treatment Status

Chapter 4.

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Alarms and Alerts 4.1 Indicators and Alarm Silence Key 4.2 Alarm and Alert Handling 4.3 Corrective actions 4.3.1 Replacing the Blood Circuit 4.3.2 Removing Air Detected During Prime Mode 4.3.3 Removing Air Detected During Run Mode

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Chapter 5.

Maintenance 5.1 Cleaning and Disinfection 5.2 Battery Testing 5.3 Periodic Maintenance 5.4 Device Checks 5.5 Storage 5.6 Return Procedure

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Chapter 6.

Hematocrit Limit Option 6.1 Theory of Operation 6.2 Technical Description 6.3 Keys, Indicators, and Screen 6.4 Features and Protective Systems 6.5 Setup 6.6 Hct Treatment Status Display 6.7 Hct Graphing

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Appendices A Replacement Parts B Specifications C Abbreviations D Alarm Testing E Catheter Compatibility Guide Figures Figure 1. Aquadex system Fluid Path Figure 2. Aquadex system: Aquadex FlexFlow console and Blood Circuit Set Figure 3. Blood Circuit Set Figure 4. Aquadex FlexFlow Control Panel Figure 5. Aquadex FlexFlow Screen Display Format Figure 6. Routing the Power Cord Through the Cord Retainer Figure 7. Setup Screens Format Figure 8. Blood Circuit Set Figure 9. Installing the Blood Pump Cartridge Figure 10. Installing the Ultrafiltrate Cartridge Figure 11. Installing Withdrawal Pressure Sensor Figure 12. Inserting Data Key Figure 13. Installing Ultrafiltrate and Infusion Pressure Sensors Figure 14. Installing Tubing into Blood Leak Detector Figure 15. Installing Tubing into Air Detector Figure 16. Attach Hct Sensor Clip to the dock located near the base of the console handle Figure 17. Hanging Ultrafiltrate Bag on Weight Scale Figure 18. Attaching Withdrawal Connector to Priming Adapter Figure 19. Inserting Priming Spike Adapter into Priming Bag Figure 19a. Hanging Priming Solution Bag Figure 19b. Upright Priming Hook Figure 20. Attaching Infusion Connector to UF Bag Priming Connector Figure 21. The Menu Screen Figure 22. The Help Screen Figure 23. Alarm Silence Key and Indicators Figure 24. Alarm Message on Console Screen Figure 25. Removing Pumps

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Figure 26. Schematic of UF 500 Hct Circuit Figure 27. Configuration of Sensor Clip and Blood Chamber/Cuvette Figure 28. Relationship Between Hct and Blood Volume Figure 29. Measured Hct and Hct Limits Figure 30. Aquadex FlexFlow Control Panel Figure 31. Hct Limit Feature Disabled

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Tables Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7.

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Control Panel Functions Prime Messages Menu Options Help Options Aquadex System Indicators Alarm/Alert Summary Control Panel Functions

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This manual describes how to set up, use, and maintain the Aquadex™ system. It is important to read and understand this manual. The safe and effective treatment of fluid overload depends primarily upon the medical skills and knowledge of the medical team with a thorough understanding of the associated medical procedures. Patient treatment must be in accordance with the specific procedures prescribed by a qualified physician. Carefully read all warnings, cautions, and instructions before use. Follow all operating and maintenance procedures described in this manual. Failure to do so could result in patient harm. Caution: Federal (U.S.) law restricts this device to sale by or on the order of a physician.

1.1 Indications for Use The Aquadex system is indicated for temporary (up to eight hours) ultrafiltration treatment of patients with fluid overload who have failed diuretic therapy, and extended (longer than 8 hours) ultrafiltration treatment of patients with fluid overload who have failed diuretic therapy and require hospitalization. All treatments must be administered by a healthcare provider, under physician prescription, both of whom having received training in extracorporeal therapies.

1.2 Contraindication There are no known contraindications to Aquadex system therapy. The intended use and contraindication of pharmacological therapy used in conjunction with the Aquadex system must be individualized by physician and deemed appropriate for each patient.

1.3 Theory of Operation The Aquadex system removes excess fluid from the patient by an advanced form of ultrafiltration, referred to as aquapheresis. Passing blood across a hollow-fiber hemofilter and removing excess fluid at the clinician-selected rate, no dialysate is used and there is no diffusion of solute across the filter membrane. While some solute is carried out by the flow of ultrafiltrate and removed from the patient by convection, the total amount is minimal. Because the Aquadex system does not use replacement fluid, solute (for example, electrolyte) clearance is clinically insignificant.

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1. Introduction

1. Introduction

Theory of Operation Figure 1 shows a schematic of blood and ultrafiltrate flow through the Aquadex system blood circuit. Blood is withdrawn from a vein through a withdrawal catheter. Plastic tubing connects a withdrawal catheter to the blood pump. Blood passes through the withdrawal pressure sensor just before it enters the blood pump tubing loop. Both the withdrawal pressure sensor and the pump loop are mounted on a plastic clip-on cartridge. During operation, the pump loop is compressed by rotating rollers that propel the blood through the tubing. After exiting the blood pump, blood passes through the air detector and enters the hemofilter. Aquadex system operation requires correct installation of the tubing into the air detector. The tubing is correctly installed when fully inserted and firmly seated into the base of the sensor. The hemofilter is bonded to another clip-on cartridge that mounts onto the ultrafiltrate pump on the right side of the Aquadex FlexFlow console. Blood enters the filter through a port at the bottom, exits through the port at the top of the filter, and passes through the infusion pressure sensor before returning to the patient. Inside the hemofilter is a bundle of hollow fibers whose walls are made of a thin material. The pores in the fiber wall material allow smaller molecules (such as water or electrolytes) to pass through, yet are too small for the passage of blood cells or larger proteins (such as albumin). The solution that passes through the fiber walls, called ultrafiltrate, fills the space between the fibers inside the transparent filter case and exits the filter through a port near the top of the filter case. After exiting the filter, ultrafiltrate passes through a blood leak detector. Aquadex system operation requires correct installation of the tubing into the blood leak detector. The tubing is correctly installed when fully inserted and firmly seated into the sensor. After the blood leak detector, ultrafiltrate passes through the ultrafiltrate pressure sensor and then to the ultrafiltrate pump. The pump rotation speed determines the rate of fluid removal. After the pump, ultrafiltrate collects in the ultrafiltrate bag that is suspended from the weight scale. When the bag is full (contains one liter), fluid removal stops (while blood flow continues) until the bag is emptied and the user restarts treatment.

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Warnings & Cautions

1.4 Warnings and Cautions This section includes warnings and cautions that must be observed at all times during Aquadex system operation. Warnings:

• Standard diuretic therapy should be considered prior to Aquapheresis™ with

the AquadexTM System. AquadexTM System circuit use beyond eight (8) hours should be used in a hospital setting. Extracorporeal blood circulation may be associated with a risk of blood loss and air embolism. Blood in the ultrafiltrate bag may indicate a health hazard to the patient. Check for the presence of blood in the ultrafiltrate bag when the blood leak detector is disabled. To avoid the risk of blood loss, inspect the Blood Circuit Set closely for leakage at joints and connections during priming and operation. Replace the circuit if tightening the connections does not stop any leaks. Because the system may not always detect blood leakage from the Blood Circuit Set, it is important to monitor the system and patient environment for blood leaks throughout treatment. It is the clinician’s responsibility to monitor parameters that are not detected by the Aquadex system under special conditions, including: Blood Circuit Set disconnection and air detection, which are disabled during Manual mode. Blood leak detection during Run mode, if blood leak detection is disabled. The extended length catheter is intended for peripheral use only with the Aquadex system. Do not place the extended length catheter in a central vein. All operation and maintenance procedures must be performed by trained and qualified personnel as described in this manual. The manufacturer cannot be responsible for patient safety under other circumstances. The Aquadex system should only be used by those trained in the clinical operation of extracorporeal fluid management therapies in a setting where appropriate responses can be delivered should problems develop in catheter care and/or fluid management. Anticoagulation therapy may cause bleeding. Do not use heparin for anticoagulation in patients with intolerance or allergy to heparin. Aquadex system treatment may be associated with a risk of hypovolemia and hypotension.

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Warnings & Cautions

• Aquadex system treatment may be associated with a risk of electrolytic

imbalance and/or loss of protein. Aquadex system treatment has not been tested for use in patients with uncontrolled hypertension. Rapid volume depletion as a result of ultrafiltration may cause irreversible damage to renal function in patients with baseline compromise in glomerular filtration rate (GFR). To avoid the risk of patient injury or death, do not use unauthorized tubing sets, hemofilters, or other accessories. To avoid possible infection, do not use the Blood Circuit Set with damaged packaging. ELECTRIC SHOCK HAZARD. Do not open the case of this device. Operate this device only with all covers, panels, and knobs properly installed. To avoid the risk of fire, do not operate this device in the presence of flammable anesthetics or other flammable gases. The Aquadex system includes air and blood leak detectors. To ensure correct operation, the Blood Circuit Set must be properly inserted into both detectors at all times during setup and use. To minimize the introduction of air into the patient, do not connect the patient until Blood Circuit Set priming (when the air detector is disabled) is complete. Ensure that the Blood Circuit Set is free of air at the end of priming. To prevent air from entering the patient, monitor the Blood Circuit Set closely when turning the blood pump by hand. Monitor patient for clinical signs of hypovolemia and hypotension as appropriate. Rapid rates of fluid removal can result in life-threatening hypotension and/or tachycardia during treatments. The Aquadex system has not been tested in patients with a hematocrit higher than 53%. The safety and effectiveness of the Aquadex system has not been established in patients: With recent infection that required parenteral antibiotics. Who are Hepatitis B surface antigen positive. Having a previously known history of hypercoagulable states such as a known history of phospholipid syndrome or history of recurrent documented thromboembolic events. Who are pregnant.

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Warnings & Cautions

• Access to peripheral circulation for therapy with the Aquadex system may be • • • • • • • • • • •

difficult or impossible in patients with poor veins or inadequate circulation. Access to central venous circulation should be limited to areas within the hospital that routinely manage patients with central venous access catheters. It is important for the clinician to balance the risks of anticoagulation with the potential benefit when deciding to use anti-coagulation therapy (for example, heparin) in conjunction with Aquadex system therapy. To reduce the risk of extravasation and infiltration, monitor the patient during catheter insertion, at the start of therapy, and during therapy as appropriate. Use aseptic technique throughout treatment to minimize the risk of infection. To prevent contamination, use the Blood Circuit Set immediately after removing its packaging and caps. Do not use the Blood Circuit Set if the package is damaged, if the components are missing or loose, or if the lines are kinked. The Aquadex system has not been designed for use with access using an arterio-venous fistula. This Equipment or System should not be used adjacent to or stacked with other equipment. If this is necessary, the Equipment or System should be observed to verify normal operation in the configuration in which it will be used. The use of the Hct option on the Aquadex System is an adjunct to patient care and is not a replacement for standard medical care for assessing patient response to fluid removal. The air detector will not detect any air introduced by a syringe through an access port distal to the air detector. Locking connectors may separate if either the male or female part is exposed to a lubricant; for example, by transfer from a lubricated, needle-less valve. The air detector will not detect any air introduced by a syringe through an access port distal to the air detector.

Cautions: All electrical installations must comply with all applicable local electrical code and the manufacturer’s specifications. Use potential equalization (ground post) in accordance with national requirements. Do not tamper with pumps or attempt to run pumps with protective knobs removed.

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Technical Description

• Do not modify the Aquadex system in any way. • All operation and maintenance procedures must be performed by trained • • • • •

and qualified personnel as described in this manual. Grounding reliability can only be achieved when the equipment is connected to an equivalent receptacle marked HOSPITAL ONLY or HOSPITAL GRADE. Refer to Instructions for Use; Medical Electrical Equipment may need special precautions regarding EMC and must be installed and put into service according to the information contained in the Instructions for Use. Portable and Mobile RF Communications equipment can affect Medical Equipment, take precautions for adequate separation. Use only approved cables and accessories. Use of accessories, transducers, and cables other than those specified may result in increased emissions or decreased immunity. Use only the data key supplied with the circuit. Keys are not interchangeable between circuits.

1.5 Technical Description The Aquadex system consists of the microprocessor-controlled Aquadex FlexFlow console, disposable Blood Circuit Set with an integral hemofilter (Figure 2), and a venous access catheter. The Aquadex FlexFlow console includes a blood pump, ultrafiltrate pump, control panel, weight scale, air detector, blood leak detector, electrical connectors for the circuit pressure sensors, and mechanical interfaces that hold the circuit in place. The console controls the rate at which the blood pump removes blood from the patient, and the clinician sets the maximum rate at which the ultrafiltrate pump extracts ultrafiltrate from the blood. The Aquadex system has three user settings: UF RATE, the maximum allowable rate of ultrafiltrate removal, and BLOOD FLOW, the maximum allowable rate of blood flow, and Hct, the hematocrit limit which when exceeded halts ultrafiltration. The console screen displays information to help the clinician prime, set up, and operate the Aquadex system. The Aquadex system requires minimal intervention during operation. All Aquadex system alarm limits are set by the Aquadex Figure 2. Aquadex system: FlexFlow console.

Aquadex FlexFlow console and Blood Circuit Set

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Modes of Operation The Aquadex FlexFlow console is a microprocessor-controlled device. In addition to the main processor, the Aquadex FlexFlow console includes a safety processor that monitors device operation and can stop the treatment if the console malfunctions. Power to operate the Aquadex system can come from AC or battery power. The internal backup battery can supply up to 30 minutes of backup power. The battery recharges during AC operation, and can be fully recharged within four hours. The Blood Circuit Set (Figure 3) is a sterile, single-patient use set. It typically takes 5 to 10 minutes to install and prime the circuit. The total blood capacity of the circuit is approximately 33 milliliters (ml) or 2 and a half tablespoons. The tubing pump loops, hemofilter, and pressure sensors are mounted on two plastic cartridges. The cartridges snap-fit onto the front of the blood and ultrafiltrate pumps. The cartridges simplify circuit setup and reduce the probability of kinks in the tubing. Pinch clamps on the withdrawal and infusion portions of the tubing set allow temporary blood path occlusion as needed. The Blood Circuit Set is streamlined to reduce clotting, has no drip chambers, and does not contain air during normal operation. Liquid removed during treatment drains into a transparent ultrafiltrate bag. The ultrafiltrate bag hangs from the console weighing scale. The ultrafiltrate bag is marked and labeled every 100 ml from 0 to 1000 ml. When the bag is full, the blood pump continues operation and the ultrafiltration pump stops until the bag is emptied. The ultrafiltrate bag includes a twist on/off drain valve at the bottom of the bag to empty the bag. The Aquadex system uses blood access catheter(s) to withdraw and infuse blood. The catheter(s) connect to the blood circuit and during treatment are secured to the skin.

1.5.1 Modes of Operation The Aquadex system has four modes of operation: Stop, Prime, Manual, and Run. There is a key for each mode on the control panel (Figure 4).

• Stop mode stops the blood and ultrafiltration pumps. The Aquadex system operation always begins in Stop mode when power is turned on. To enter Stop mode from any mode, press the STOP key.

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Modes of Operation

• Prime mode fills the circuit with saline and displaces air from the circuit before connection to the patient.

Figure 3. Blood Circuit Set

The Aquadex system automatically detects when the priming sequence is complete. The system cannot enter Manual or Run mode without successfully completing prime. Pressing the PRIME key has no effect unless the system is in Stop mode. To enter Prime mode from Stop mode, press the PRIME key, then press ACCEPT to confirm the request.

• Manual mode advances saline, blood, or

air through the circuit. Pressing the MANUAL key has no effect unless the system is in Stop mode and has successfully completed prime. Disconnect and air detection alarms are disabled in Manual mode. To enter Manual mode from Stop mode,press and hold the MANUAL key. Manual mode is in effect as long as you press the MANUAL key, up to one minute. When the key is released or one minute elapses, the system enters Stop mode.

• Run mode withdraws and infuses the patient’s blood while performing

ultrafiltration at the set BLOOD FLOW and UF RATE. The system only performs ultrafiltration when blood flow is greater than 88% of the BLOOD FLOW setting. Pressing the RUN key has no effect unless the system is in Stop mode and has successfully completed prime.

1.5.2 Data Key A data key is supplied with each circuit and facilitates a number of system functions: Determination of circuit type: The console reads the circuit type and configures the system maximum blood flow and UF rate according to circuit type. Reference Appendix B specifications for details.

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Keys, Indicators & Screen Calculation of circuit life: Each data key holds an individual serial number which enables the console to calculate the time elapsed on a circuit even after power cycling. A data key will be considered used once prime mode has been initiated on a console. Removing a new circuit from a console will result in the console displaying the previous circuit type as long as prime mode was not started on the new circuit. Information on the current circuit type in use and total fluid removed are shown at the bottom of the screen.

1.5.3 Keys, Indicators, and Screen The Aquadex system control panel on the Aquadex FlexFlow console (Figure 4) includes keys, indicators, and a screen.

Figure 4. Aquadex FlexFlow Control Panel

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Keys, Indicators & Screen

Table 1. Control Panel Functions Panel element

Function

ON/OFF key Powers on the console. The console is ON if an indicator on one of the mode keys is lit. To turn power on, press the ON/OFF key momentarily. To turn power off (available only from Stop mode), press and hold the ON/OFF key for 1 second. Power indicators

Indicates the power source:

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The indicator in the center of the battery symbol flashes to indicate battery operation.

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The green indicator in the center of the plug symbol lights to indicate AC power. STOP key Enters Stop mode (always available), stops ultrafiltration and blood pumps. The indicator on STOP key indicates Stop mode.

PRIME key Enters Prime mode (available only from Stop mode), to prime circuit and remove air in preparation for patient connection. To confirm selection, press the ACCEPT key within a short period of time. Green indicator on PRIME key indicates Prime mode.

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Keys, Indicators & Screen

Panel element

Function

MANUAL key Enters Manual mode (available only from Stop mode and after a successful prime), allows manual advancement of saline, air, or blood through the circuit. Green indicator on MANUAL key indicates Manual mode. RUN key Enters Run mode (available only from Stop mode and after a successful prime), to begin ultrafiltration. Green indicator on RUN key indicates Run mode. ACCEPT key Confirms a request to enter Prime mode, accept a current MAX RATE setting, or select a Menu function. CLEAR key Clears active alarms, cancels an alarm silence, cancels a request that requires confirmation, and exits Menu functions. Up and down arrow keys Scrolls through Menu functions and Help text, increases and decreases settings for UF RATE, BLOOD FLOW, alarm volume, and contrast. UF RATE key Sets the maximum allowable rate of ultrafiltration

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Keys, Indicators & Screen

Panel element

Function

BLOOD FLOW key BLOOD FLOW

Sets the maximum allowable rate of blood flow.

Alarm silence key Mutes the audible alarm for 2 minutes. Pressing CLEAR during an alarm silence period cancels the alarm. Yellow indicator on Alarm Silence key indicates Alarm Silence is active. HELP key Provides contextual help if an alarm or other interactive screen is displayed. Displays a menu of help topics, if no alarms are present or if contextual help is displayed. Contrast key Sets screen contrast. To adjust, press the Contrast key, then up and down arrow keys. The contrast adjustment period expires if you press CLEAR or do not press an arrow key within 10 seconds of pressing the Contrast key. MENU key Allows you to view reports and alarm history, set date and time, set speaker volume, enter the Loading the Blood Circuit Set help screens, set default rates/limits and view the system configuration. mmHg key mmHg

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Displays a report of periodic measurements of system operation (e.g. blood flow, pressures, Hct). All values displayed are averaged over a 20 minute period.

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Keys, Indicators & Screen

Panel element

Function

HCT key Sets the Hct Limit which when exceeded, halts ultrafiltration.

Hct GRAPH key

Displays a menu of reports available. FUNCTION keys

F1

F2

F3

F4

Reserved for future use.

Screen The console screen (Figure 5) displays:

• Current mode of operation and length of time in mode or treatment. • Type of circuit attached. • UF RATE setting, monitored blood flow and current setting, monitored Hct and Hct limit, current circuit pressures and fluid removed.

• Flashing alarm/alert message (if active) and graphic showing affected components.

• Other information, including possible alarm/alert remedies, blood leak detector disabled (if active), Help messages, and Menu information.

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Figure 5. Screen Display Format

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Features & Protective Systems

1.5.4 Features and Protective Systems The Aquadex system incorporates several advanced features and systems to protect the patient from risks associated with extracorporeal blood circulation and hypotension.

1.5.4.1 Pressure Monitoring The Aquadex system continuously receives input from three pressure sensors: blood withdrawal pressure, blood infusion pressure, and ultrafiltrate pressure. The pressure sensors are single-use components supplied as a part of the Blood Circuit Set. To function properly, the sensors must be plugged into the corresponding receptacles in the console. The Aquadex system detects disconnected sensors, and alarms to notify the user. The signals from the withdrawal and infusion pressure sensors are also used to detect the occlusion and disconnect conditions in the blood circuit. Blood Circuit Disconnect Detection The Aquadex system detects disconnect by monitoring pressures in the withdrawal and infusion lines of the blood circuit. Blood Access and Circuit Occlusion Detection Like disconnection, the Aquadex system detects blood circuit occlusions by monitoring pressure. An occlusion may be due to clotting or kinking of a blood tubing or catheter. Such occlusions require user intervention. Note: Occasionally occlusions are associated with blood access. Patient activity can cause temporary occlusion of withdrawal and infusion catheters. These occlusions often disappear quickly. To reduce nuisance alarms caused by such short-term occlusions, the Aquadex system attempts automatic recovery before activating an alarm. In response to the occlusion, the system immediately reduces pump speed to prevent excessive positive infusion pressure or negative withdrawal pressure. Decreased blood pump speed indicates that the system has detected an occlusion, and avoids potential damage to the circuit. Occlusion recovery in the withdrawal catheter is handled differently than an infusion line occlusion. A withdrawal occlusion is typically caused by the

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Features & Protective Systems collapse of a vein around the catheter tip. Such collapses usually cause blood flow to diminish rapidly, and then stop completely. To attempt recovery, the system reverses the blood pump briefly by infusing small amount of blood back into the collapsed vein, then restoring the normal pump rotation direction. Note: The Aquadex system controls blood flow in the circuit. If blood flow is reduced to below 88% of the current setting as a result of an occlusion, ultrafiltrate removal stops automatically. This reduces the probability of clotting in the filter that can occur with sluggish blood flow inside the fibers. Ultrafiltration restarts automatically when normal blood flow resumes. Occlusions in the Filter and Ultrafiltrate Collection System The ultrafiltrate pressure sensor detects occlusions of the filter membrane or the ultrafiltrate tubing between the filter and the ultrafiltrate pump. If the ultrafiltrate pressure sensor detects excessive negative pressure, the system declares an Ultrafiltrate Line Occlusion alarm.

1.5.4.2 Compensation of Effects of Height on Pressure Pressure monitoring plays an important role in Aquadex system operation. When measuring pressure in a liquid-filled tube, it is important to consider the height difference between the pressure sensor and the pressure measurement location. For example, if a catheter inserted in a patient’s arm is 0.5 meters (20 inches) lower than the Aquadex FlexFlow console, the measured infusion pressure can be as much as 37 mmHg below the actual pressure (which would include the weight of the fluid column). To account for the height difference between the console and the patient, the Aquadex system calibrates (“zeroes”) pressure sensors at the beginning of treatment just after the operator presses the RUN key. Note: For accurate sensor calibration, it is important that neither the patient nor the console move for approximately five seconds after pressing RUN: otherwise, a Motion Detected or Unexpected Pressure alarm may occur. If such an alarm occurs, re-enter Run mode with the patient and all components at rest.

1.5.4.3 Air Detector The Aquadex FlexFlow is equipped with an air detector that can detect an air bubble passing through the blood tubing. The Aquadex system is designed to ensure accurate coupling between the tubing and the sensor.

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