Decision to Take Up a Patient in The Presence of Arrhythmias

Dr. Vasanthi Vidyasagaran^*

Department of Anaesthesiology, Kauvery Hospital, Chennai, Tamilnadu, India

Case 1

A 50-year-old man was brought to the emergency department for an obstructed inguinal hernia. He was a chronic smoker and was also under the influence of alcohol at that time. Relevant medical history was that he was a known case of cardiac arrhythmia (atrial fibrillation) and had discontinued his medication.

He could not give a detailed history about the drugs or the duration of medication. On examination, his pulse rate was 115/ minute and irregularly irregular. BP was 110/70, and lungs were clear. His preoperative ECG showed absent P waves with varying RR intervals. Chest x-ray was normal, and echo showed no LA clot, EF of 54 % and normal valves.

Here we had a patient with history of noncompliance to antiarrhythmic drug treatment. This patient was prone to tachyarrhythmia in the perioperative period which may compromise safety. However, due to the emergency nature of his condition, risks were explained to the patient and family, and was taken up for emergency hernioplasty.

The anaesthetic goals included:

To prevent hypotension that may compromise blood supply to the coronaries and cause uncontrollable tachyarrhythmia.
To appropriate fluid and electrolyte balance, particularly potassium and magnesium.
To prevent thromboembolic phenomenon – Anticoagulation in form of low molecular Heparin – may need to be commenced in perioperative period.

It was decided to perform the surgery under hernia block, as it was the safest technique for this patient. (smoker, AF, under influence of alcohol). The surgery was completed as planned, and the patient made an uneventful recovery. Postoperatively after cardiology review, drugs were recommenced.

Case 2

A 60-year-old woman who was obese, hypertensive, and diabetic, with an extremely anxious personality, was posted for elective ventral hernia repair. She mentioned history of anxiety and occasional palpitations that usually settled on its own. Preoperative ECG, echo, and cardiology review were noted to be normal.

As patient was wheeled into operation theatre, she was anxious about surgery and when monitors were placed, it was noticed that her heart rate was 197â€“200/min. Rhythm was recognized as supraventricular tachycardia. Patient was conscious and oriented; BP 90/46 mm Hg and oxygen saturation was 94% on air. A 100% oxygen was administered via face mask and 2 mg midazolam administered.

Chest was clear, no sign of impending heart failure. Metoprolol IV was administered slowly – 2 mg boluses up to 10 mg, heart rate came down to 156/min, still in SVT. A 12 lead ECG was done and Adenosine was given. However, the response was very short and hence, Amiodarone 150 mg was given slowly IV over 20 minutes, and 150 mg was added to an infusion.

Rhythm converted to sinus with a rate of 76/min. Blood pressure was stable at 100/60. Surgery was cancelled for the day. It was decided to achieve rate control before elective surgery. Cardiologist reviewed the patient and diagnosed an aberrant tract causing SVT, which needed ablation. Patient underwent radiofrequency ablation in next 48 h. One week later elective surgery was done as open procedure under epidural anesthesia. She did not have any further cardiac event.

Discussion

Atrial fibrillation and SVT are not uncommon arrhythmias and anesthesiologists must be able to identify and manage them efficiently to prevent untoward consequences. Perioperative AF is a risk factor for ischemic stroke, and healthcare providers should consider appropriate antiarrhythmic and antithrombotic measures in surgical patients.

In the first scenario, we had a patient who was a known case of atrial fibrillation. The management in such scenarios are

Preoperative control of rate and rhythm
Preoperative echo to rule out any left atrial thrombus to prevent perioperative risk of embolus in addition to assessment of static cardiac function
Manage perioperative anticoagulation – in patients on Warfarin, stop Warfarin and use bridge therapy with Heparin
Perioperative Digoxin: drug interactions to be borne in mind
Avoid triggers that push to tachyarrhythmia: hypovolemia, stress, electrolyte imbalance (especially potassium) and pain. If rate control is required, beta-blockers may be used.

It is important for all practicing anesthetists to be familiar with common regional blocks, which will come in handy in emergency situations like this.

In the second patient, we had a case of paroxysmal supraventricular tachycardia, due to an aberrant tract, triggered in preoperative setting related to stress and anxiety, diagnosed just prior to anesthesia.

It was identified by the anesthetist at the right time prior to induction and managed successfully. If anesthesia had been induced without noticing it, patient may have suffered cardiac event under anesthesia and it may be considered as anesthetic morbidity.

Management guidelines of SVT suggest:

Rate and rhythm control
Identify triggers – ischemia or aberrant tract
Follow algorithm as per resuscitation council guidelines

Some patients may have atrial ectopics, and paroxysmal atrial tachycardia due to long standing effect of drugs, like in asthmatics, and COPD patients. In such patients under anesthesia, these rhythms may be benign and not persistent. They can be left alone as they are usually self-resolving provided the patient is kept hemodynamically stable and well oxygenated. It is important to avoid sympathomimetic drugs such Adrenaline infiltration in such patients which may tilt the balance and precipitate significant arrythmias.

References

Camm AJ, Kirchof P, Lip GYH et al. Guidelines for the management of atrial fibrillation: the task force for the management of atrial fibrillation of the European Society of Cardiology (ESC). Eur Heart J 2010; 31:2369-429 2.
NICE Guidelines: Preoperative tests for elective surgery: 2003.
ALS guidelines for management of tachyarrhythmia. https://www.resus.org.uk/pages/periarst.pdf
Lip G, Douketis J. Management of anticoagulation before and after elective surgery. UpToDate, 2014.
Algorithms for Advanced Cardiac Life Support 2017 Mar 30, 2017. Version control: This document is current with respect to 2015 American Heart Association Guidelines. https://www.acls.net/aclsalg.htm

Decision to Take Up a Patient in The Presence of Arrhythmias