Emergencies (arrhythmias and anesthesia)

Treatment of acute malignant arrhythmias / electrical storm has been commenced in 4 steps:

  • Defibrillate/resuscitate if necessary
  • Admit to specialized cardiac care unit / intensive care unit
  • Stop / remove / treat provocative circumstances: 1) Treatment of fever by antipyretics and/or cooling together with treatment of fever origin; 2) Stop arrhythmogenic drugs/substances and/or treat arrhythmogenic drugs/substances overdose, 3) maintain normal electrolyte levels.
  • Therapeutic treatment with: 1) isoproterenol/isoprenaline (1 to 2 µg bolus i.v. followed by continuous infusion of 0.15-2.0 µg/min) and/or 2) quinidine (300 to 1500 mg /day). Aim at quinidine plasma levels of 1-3 µg/mL or 3.5-11 µmol/L. Please note that low dosages of quinidine in adults (i.e. ≤600mg per day) may be sufficient (Marquez et al.). Be aware that for children dosing is often tailored to bodyweight (and also read the next paragraphs!). As a reference, in adults an isoproterenol regimen of 0.003±0.003 µg/kg/min has successfully been used by Ohgo et al. during electrical storm and 0.01 to 0.02 µg/kg/min has been used by Kasanuki et al. to prevent induction of VF during programmed stimulation, while 0.15-2.0 µg/min (without bodyweight) after a 1 to 2 µg bolus has been used successfully in adults during electrical storm. A quinidine dosage for children is 30–60 mg/kg/day given in 4 divided doses as used by Probst et al., and Suzuki et al.
  • Please note that some patients (often children) with an SCN5A mutation may have a (‘use-dependent’) conduction phenotype (recognized by the broad QRS complexes which further broaden with higher heart rates) as opposed to a Brugada phenotype. In the case of fever and the associated tachycardia, this combination may result in electric storms. Isoproterenol in these cases may actually have devastating effects because of the associated increment in heart rate that may further slow conduction and may add to the arrhythmogenic substrate. As opposed to isoproterenol, in these patients beta-blockers are indicated to slow down the heart rate. See Chockalingam et al. 2011 and Chockalingam et al. 2012.
  • Advised references: Ohgo et al. 2007, Watanabe et al. 2006, Probst et al. 2007, Marquez et al. 2012.
  • Please do inform us on the result of your emergency arrhythmia case to help building up experience. You can reach us through the contact page and we can discuss the case thereafter by email or otherwise.

Anesthesia:

  • Please note that Brugada syndrome patients may have less sodium channels available for conduction and that this limits their conduction reserve. This implies a possible pro-arrhythmic risk of the use of drugs that have sodium channel blocking properties (further lowering conduction reserve and promoting a pro-arrhythmogenic substrate), such as some anesthetic drugs.
  • Please note that although propofol may result in malignant arrhythmias in some Brugada syndrome patients, it has been used uneventfully in numerous other Brugada syndrome patients. The ‘Avoid’ labelling is particularly meant to address this issue and to make sure that appropriate measures are taken to minimize pro-arrhythmogenic potential. When appropriate measures are taken (see below)  anesthesia with propofol can most often be performed safely in Brugada syndrome patients.
  • An excellent review on anesthesia in Brugada syndrome has been written by Kloesel, Ackerman and colleagues in the Canadian Journal of Anesthesia in 2011 (PMID: 21698509). We strongly advise to use this review for guidance and background information on published cases until 2011. Other reviews currently have lower appreciation by BrugadaDrugs.org.
  • The following steps are advised:
    1. Inform your surgeon on the difficulties that may be associated with the anesthesia, that precautions will be taken and that surgery might need to be paused during the operation when (an increase in) pro-arrhythmic conditions are discovered that need attention.
    2. Investigate the risk of the patient for arrhythmias;
      • Did the patient have documented arrhythmias before, and if so, under which circumstances?
      • Does the patient currently exhibit a type-1 Brugada ECG (example found on this page)? If yes, this implies larger arrhythmic risk and should result in even more care to minimize pro-arrhythmic risk and availability of measures to treat arrhythmias..
      • Does the patient currently have fever? If yes, this implies larger arrhythmic risk and temperature should be normalized by any means.
      • Does the patient have an ICD? If yes, probably the previously presumed arrhythmia risk is higher.
      • Does the patient have a loss-of-function SCN5A mutation? If yes, the risk of the use of drugs with sodium channel blocking properties may be higher. When the patient has two loss-of-function SCN5A mutations, the risk of the use of drugs with sodium channel blocking properties is considered extremely high and it should be strongly considered to avoid  drugs with sodium channel blocking properties.
      • Does the patient currently have electrolyte abnormalities? If yes, it is probably best to correct these abnormalities as much as possible, especially (severe) hyperkalaemia as this may cause decreased sodium current.
    3. Prepare the operating theatre for recognition and treatment of ventricular arrhythmias
      • Resuscitation equipment should be ready for use (external defibrillator ready and defibrillation pads attached). Switch off anti-tachycardia therapy of the ICD if needed (e.g. when surgical electrocautery is going to be used, as this could result in oversensing and inappropriate anti-tachycardia ICD therapy/shocks). And switch on anti-tachycardia therapy of the ICD again after the procedure! As long as anti-tachycardia therapy is switched off the patient should be on ECG monitoring. Brugada patients are not often in need of anti-bradytherapy. If anti-bradytherapy is programmed on this should be temporarily re-programmed to non-tracking modes (VOO or DOO) when surgical electrocautery is going to be used as electrocautery may result in oversensing and inappropriate pacing inhibition, or may be switched off when appropriate. Also the anti-bradytherapy settings should be restored after the procedure!
      • Put the patient on continuous ECG monitoring and do the utmost to be able to also continuously monitor the right precordial ST segments (i.e. V1, V2, and V1 and V2 in the 3rd intercostal space). When ST elevation occurs in these leads one should realize that this infers an increase in arrhythmic risk and one should try to discover why these changes occurred and intervene (e.g. by administration of isoproterenol, lowering temperature, pausing the operation etc., see below).
      • Have anti-arrhythmic drugs ready for use (also see the paragraph on arrhythmias above), at least isoproterenol/isoprenaline, and quinidine if available (quinidine is only available for oral administration, so prepare gastric access). If a rate-dependent/use-dependent phenotype (e.g. children with an SCN5A mutation) is anticipated, strongly consider replacing isoproterenol/isoprenaline by beta-blockers when tachycardia is associated with rise in ST-segments or increase in PR interval and/or QRS width.
      • Have continuous core temperature monitoring and have cooling equipment ready for use to lower temperature (aiming at normothermia or hypothermia), as an increase in temperature will increase arrhythmic risk and these arrhythmias will be less likely to occur, return or to be incessant upon cooling.
    4. Consider the anesthesia induction drugs (see Kloesel, Ackerman et al). Propofol has been used uneventfully in many cases but could turn pro-arrhythmic (especially in prolonged, i.e. days, infusion). Thiopental and inhalation anesthesia have so far not been associated with adverse events. For further details see Kloesel, Ackerman et al.
    5. Lidocaine use for local anesthesia (e.g. by dentists) does seem to be safe when combined with adrenaline/epinephrine (e.g. xylocaine dental/epinephrine or articaïne/epinefrine (Ultracain® or Septanest®) 1:100,000) and the amount administrated is low as it results in a local effect only (Theodotou 2009). Also in a controlled setting such as during ICD (implantable cardioverter defibrillator) implantation, there have been no descriptions of untoward events although the amount of administered lidocaine can be substantial, still the utmost care should be taken to avoid systemic injection. When applied on the skin (e.g. for children requiring venapuncture or vaccination) it is also extremely unlikely that there will be systemic effects, and this will thus most probably also be safe to do.
    6. When surgical techniques are used that may precipitate brady- or tachy-arrhythmias (e.g. quick inflation or deflation of a pneumoperitoneum during laparoscopic procedures / procedures that enhance vagal tone), advise your surgeon to perform these task slowly and cautiously as patients with Brugada syndrome may be more susceptible to these situations.
    7. Strongly consider post-operative ECG monitoring until all anesthetics have been eliminated (≥ 5 half lives).
  • Please do inform us on the result of your anesthesia case to help building up experience. You can reach us through the contact page and we can discuss the case thereafter by email or otherwise.