Our peri-anesthesia team recently encountered a question: Are there specific peri-anesthesia considerations while placing epidural blood patch (EBP) in patients wearing wearable cardioverter defibrillator (WCD)? In the United States (US), LifeVest® (ZOLL Medical Corporation, Pittsburgh, Pennsylvania) was the only US Food and Drug Administration (FDA)-approved WCD available since 2001 until ASSURE® (Kestra Medical Technologies, Inc., Kirkland, Washington) got FDA-approval in 2021. LifeVest® delivers up to five shocks of 150 joules each while ASSURE® delivers up to five shocks of 170 joules each after detecting shockable rhythm if person wearing WCD has become unconscious during the detected shockable rhythm.[1] People wearing WCD, if conscious, can personally delay delivery of shocks by responding to WCD alarms alerting them that shocks are imminent unless delayed by person wearing WCD being conscious. However, under anesthesia-sedation, patient wearing WCD cannot personally delay delivery of shocks even if WCD-detected shockable rhythms are falsely positive. Therefore, anesthesia providers prefer to replace WCD with manual monitors/defibrillators to monitor these patients under anesthesia-sedation and if needed, provide emergent cardioversion/defibrillation because these patients’ pre-morbid conditions have required them to wear WCD for mitigating their high-risk for unwitnessed shockable rhythms followed by unwitnessed sudden cardiac arrest. However, during EBP placement, patients may not receive anesthesia-sedation so patients wearing WCD may remain conscious enough to delay delivery of shocks in case falsely positive shockable rhythms are detected by their WCD. Moreover, unlike EBP placement in thoracic region,[2] WCD garment, designed to always remain in contact with underlying bare thoracic skin for delivering gel over therapy electrodes in preparation for imminent shock if needed, will not interfere with EBP placement in lumbar region. Additionally, injection of blood in epidural space during EBP placement differs from the injection of anesthesia-analgesia medications in spinal-epidural space which can risk patients becoming unconscious thus patients wearing WCD losing consciousness to delay delivery of shocks if falsely-positive shockable rhythms detected by their WCD. However, considering that loss of consciousness like vasovagal syncope unrelated to EBP may happen during its placement, peri-anesthesia teams, and their healthcare institutions can mandate logistically safe policy to replace patients’ WCD with manual monitor/defibrillator during peri-anesthesia care including during EBP placement. If peri-anesthesia teams have rarely encountered patients wearing WCD in their practice, patients religiously wearing WCD and following its instructions appropriately may be more well-verse with managing their WCD and hence can actively guide peri-anesthesia teams for appropriately replacing their WCD with manual monitor/defibrillator in preparation for their peri-anesthesia care. Besides avoiding anesthetized-sedated patients receiving inadvertent shocks for their WCD-detected falsely-positive shockable rhythms, peri-anesthesia teams also want to avoid bystanders receiving shocks while managing their anesthetized-sedated patients because unlike implantable cardioverter defibrillator (ICD) designed to deliver shocks of up to 80 joules each,[3] WCD designed to deliver shocks of 150–170 joules each carry more risk of bystanders receiving shocks. When shockable rhythms are detected by WCD, vibration, audible and visible alarms get activated in WCD. Although WCD-delivered shocks may get transmitted to bystanders who are in physical contact with patients being shocked by WCD, these alarms caution patients as well as bystanders about the impending delivery of shocks from WCD. To avoid receiving shocks after these alarms from WCD, patients if conscious can cancel delivery of shocks from WCD by immediately holding a pair of response buttons on LifeVest® or immediately pressing Alert Button on ASSURE®, thus reducing inappropriate delivery of shocks from WCD with patients being conscious enough to cancel the impending delivery of shocks from WCD. Although peri-anesthesia teams may decide to themselves manage the pair of response buttons on LifeVest® or Alert Button on ASSURE® in their anesthetized-sedated patients wearing WCD, WCD-manufacturers recommend that only patients use response buttons or Alert Button to cancel impending delivery of shocks from WCD. Peri-anesthesia care of WCD-wearing patients whose numbers may be increasing warrants education for peri-anesthesia teams about appropriate WCD-management just like WCD-wearing patients and their family-caregivers have been trained by WCD-manufacturers as per their WCD-prescribing cardiologists. Summarily, although not warranted during EBP placement, it may be easier for peri-anesthesia teams and safer for peri-anesthesia management to replace patients’ WCD with manual monitor/defibrillator to which peri-anesthesia teams are accustomed and attuned.
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REFERENCES
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