MAUDE Adverse Event Report: DATEX-OHMEDA, INC. AISYS CS2; ANESTHESIA GAS MACHINE

Device Problem Obstruction of Flow (2423)

Patient Problems Hypoxia (1918); Loss Of Pulse (2562)

Event Date 10/26/2017

Event Type  Injury  

Manufacturer Narrative

Ge healthcare¿s (gehc) investigation into the reported occurrence is still ongoing.A follow-up report will be issued when the investigation has been completed.The customer contact reported no further patient information available.(b)(4).The user has not made the device available for inspection by gehc as of the time of this mdr submission.User filed medwatch reports mw5073176 and mw5073555.: ge healthcare¿s (gehc) investigation into the reported occurrence is still ongoing.A follow-up report will be issued when the investigation has been completed.

Event Description

Ge healthcare is in receipt of two user filed medwatch reports (mw5073176 and mw5073555) that refer to the same reported event.Mw5073176 states: "a female developed intraop hypoxic arrest.Following routine checkout of aisys cs2 anesthesia machine and preoxygenation, ga was induced.Pt quickly desaturated and immediately mask ventilated with anesthesia circuit and intubated with glidescope uneventfully.During ventilation using anesthesia circuit, there was no chest rise.Initially, problem with intubation was suspected and ett was immediately changed and another ett was placed uneventfully using direct laryngoscopy.Again, ventilator was not possible using anesthesia circuit.Bag-valve-ett ventilation using stand alone oz2 tank was successful.Pt sustained hypoxic pea arrest and resuscitated with rosc.Inspection of the aisys cs2 anesthesia machine revealed leak test adapter on the inspiration flow sensor outlet producing complete circuit obstruction and failure to delivery gas and ventilate the pt.The aisys cs2 user's ref manual recommends preoperative "optional" low p leak test.In the non-acgo aisys cs2 machine, the positive pressure "low p leak" test is listed as optional in the electronic checkout menu.Two different types of leak test adapters are available for this purpose.In the nonacgo aisys cs system, the manufacturer recommends occluding the inspiratory flow sensor outlet with the leak test adapter for performing positive pressure ¿low p leak test¿.There are several inherent problems associated with performing positive pressure low p leak" test using mfr provided adapters (especially brown adapter) in the non-acgo aisys cs2.Brown adapter allows operator to attach anesthesia circuit to the outer end of the adapter.This may not be recognized by the operator at the start of the case and result in inability to deliver gas to the pt.There are no "sensors" on the machine end of the leak test adapter, warning the operator or disabling the "start case" function on the machine.The electronic "low p leak" test sequence doesn't provide warning about the hazard of breathing circuit occlusion."start case" function on the electronic display remains active even when the leak test adapter is attached to the inspiratory flow sensor outlet.This can happen if the leak test adapter is attached to the inspiratory flow sensor outlet and low p leak" test not triggered.In this scenario, all functions of anesthesia machine, except mechanical ventilation, remain operational including volume, pressure and gas monitoring.Apl valve, bag mode, and oxygen flush.The operator of the machine is able to adjust the airway pressure using flows and apl valve while squeezing the bag.However the leak test adapter does not allow gas delivery from machine to the breathing circuit and the pt due to total occlusion at the inspiratory flow sensor outlet.This creates a dangerous situation and potentially lethal crisis and injury to the pt.In a hypoxic and hypoventilatory crisis situation, anesthesia providers often first focus their attention toward the pt, and not immediately recognize machine related problem (in this scenario, inspiratory flow occlusion by the leak test adapter.Furthermore when compared with other anesthesia machines, the locations of the inspiratory and expiratory flow sensor outlets on aisys cs2 anesthesia machine are not easily visible (hidden under inspiratory and expiratory valve assembly) and any attachments at these outlets are not clearly noticed by the operator.This highlights the fact that this flaw along with hidden position of the flow sensor outlets in aisys cs2 are unsafe features of this machine and all anesthesia providers who use this machine must be aware of these drawbacks." mw5073555 states: "a female with chief complaint of poor sleep, excessive snoring and frequent awakenings was scheduled for adenotonsillectomy under general anesthesia.The patient desaturated with induction of anesthesia, and the surgical procedure was aborted with the patient subsequently transferred to an outside facility for continued care.The inspiratory limb of the aisys cs2 was noted to have the low pressure check, double-ended stopper in place, resulting in the patient not receiving oxygen.There are potentially multiple design issues related to optional low peak pressure testing.There is a lock-out safety feature on the anesthesia machine that prevents any further use of the machine once the low pressure check is started.If the rubber stopper is placed, but the test is not started, no alarm fires and no lock-out occurs.Further, regardless of the initiation of the low pressure test, the circuit does not alarm if the inspiratory limb is occluded.Additionally, the alarms on the anesthesia are not specific to a machine/circuit issue and could be attributed to patient condition.The design should consider incorporating variations in the sound and length of alarms to indicate the issue stems from the anesthesia circuit, rather than the patient's condition.Moreover, the aisys cs2 includes two low pressure stoppers, a flat backed stopper and a double-ended stopper that perfectly fits the inspiratory limb of an anesthesia circuit onto it, which fully occludes the circuit and prevents delivery of any gas flow.Finally, buyers of the equipment since the last fda review of this machine may not be adequately aware of warned of these design challenges which lack maximum system safeguards to best support providers delivering complex surgical anesthesia services.".

Manufacturer Narrative

The root cause of the complete loss of ventilation was a misconnection of the inspiratory limb of the patient circuit to the end of a red test plug that was not provided with the aisys cs2 device and was not properly removed from the inspiratory port prior to placing the device into use.

• Brand Name: AISYS CS2
• Type of Device: ANESTHESIA GAS MACHINE
• Manufacturer (Section D): DATEX-OHMEDA, INC.; 3030 ohmeda dr,; madison, WI
• Manufacturer Contact: john szalinski ; 3000 n grandview blvd.; waukesha, WI
• MDR Report Key: 7128006
• MDR Text Key: 95172094
• Report Number: 2112667-2017-02359
• Device Sequence Number: 1
• Product Code: BSZ
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K132530
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: health professional,other,use
• Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date: 03/27/2018

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 12/19/2017
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Other Device ID Number: SEE BLOCK H10
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Was the Report Sent to FDA?: No
• Date Manufacturer Received: 03/08/2018
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 01/01/1970
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: N
• Patient Sequence Number: 1
• Patient Outcome(s): Other
• Patient Age: 13 YR
• Patient Weight: 41