Being a resuscitation educator commonly requires discussion of the dilemmas of arrhythmia management. This is an area we don’t delve into everyday so achieving true ‘expertise’ is a challenge.
Guidelines often come to the rescue in such life-threatening and time dependent situations. The American Heart Association (AHA) has released updated recommendations for the management of ventricular arrhythmias:
ACS generally causes VF or polymorphic VT.
A scar from an old MI generally causes monomorphic VT.
VT/VF storm generally occurs within 3 months of an MI. It is defined as >/= 3 episodes of sustained VT, VF, or appropriate ICD shocks in a 24-hour period.
If in doubt with wide complex tachycardia, assume it’s VT (class I).
For hemodynamically stable VT, procainamide is the preferred pharmacologic agent (class IIa). However, cardioversion remains a class I recommendation.
In hemodynamically unstable ventricular arrhythmias, electricity is undoubtedly first priority. If that fails, amiodarone is the preferred pharmacologic agent (class IIa).
IV beta blockers may be useful (class IIa) for patients with:
VT/VF storm despite DCCV and antiarrhythmics
Polymorphic VT due to MI
Adrenaline 1mg every 3-5 minutes “may be reasonable” in cardiac arrest (class IIb).
Consider emergent PCI in all patients after out-of-hospital cardiac arrest, particularly with initial shockable rhythm. Absence of STEMI does not rule out culprit coronary lesion and may be seen in 30% of patients.
Contrary to common teaching, accelerated idioventricular rhythm (AIVR) is not a marker of reperfusion. Instead it is more strongly associated with infarct size.
Some drugs can worsen or unmask Brugada syndrome. (drugs of concern include procainamide (not available in Australia), flecainide, TCAs, lithium, propofol, cocaine, cannabis and alcohol).
Digoxin isn’t the only cause of bidirectional VT. Catecholaminergic polymorphic VT (exercise or stress induced VT) can also cause it.
Long QT syndrome: males in childhood and postpartum females are at greatest risk for ventricular arrhythmia.
Given history of diabetes, hypertension and sudden onset of pain the patient was admitted for serial troponin. Despite the x-ray and clinical examination there was concern about aortic pathology and the ED team requested a ‘CT aortogram’
While waiting for CT scanning the patient developed a sore throat and dysphagia
Further neck clinical examination:
diffusely tender anterior neck bilaerally
feeling of fullness but no lymphadenopathy appreciated on examination
At this time the patient reported worsening dysphagia
The vital signs remained normal but there was profound drooling and concerns about the status of the airway in view of the neck swelling
The anaesthetics team were consulted. They shared the teams concerns about the airway. Early intervention was considered pertinent in order to protect the airway – an awake fiberoptic intubation was completed in the Operating Room
The patient was commenced on intravenous (IV) ceftriaxone and a CT ‘soft tissue neck’ was requested
This CT demonstrated extensive swelling throughout neck deep space planes “consistent with haematoma“
The patient’s NOAC (Apixaban) was withheld and ceased on the medication chart
The patient was continued on their broad spectrum IV Antibiotics
The treating team made the decision to refer for ‘exploration of neck’ in the operating theatre
Later the follow up of microbiology results ‘grew Streptococcus’ from local cultures
Some Key Learning Points
Initial Emergency Department (ED) presentations may be atypical in patients with chronic disease.
In this case inter-scapular pain focussed the initial ED assessment to rule out cardiac, pulmonary and aortic pathology.
A pearl from this case is it is pertinent to “continue to observe patients” with on-going symptoms
In the Emergency Department setting we should have low threshold for investigation of new or progressive symptoms (such as severe neck pain)
Patients on ‘NOACs are at high risk’ of uncontrolled non-compressible bleeding
Where there are concerns about neck swelling consider early interventions to protect the airway – whilst starting treatment (e.g. antibiotics, steroids, nebulisers)
Make referrals to Ear Nose and Throat (ENT) surgeons and anaesthetics using an “ISBAR” handover and with an appropriate sense of urgency (neck swelling can be a time-dependent emergency)