Mars Brimhall, SRNA - Midwestern Bachelors in Biology and Chemistry - - PowerPoint PPT Presentation

Mars Brimhall, SRNA - Midwestern

• Bachelors in Biology and Chemistry

at Northern Arizona University.

• Nursing degree from Northern

Pioneer College.

• Nursing experience in the ER, ICU,

and CV/ICU settings.

• Currently a Student Registered

Nurse Anesthetist (SRNA) @ Midwestern University, Glendale – AZ.

• And Yes, I love space jokes …

Mars Brimhall

What is it?

• Occurs because of multiple

reentry circuits in the atria.

• The atria are depolarized at a

rate of 400 to 600 beats/min.

• These rapid impulses cause the

muscle of the atria to quiver (fibrillate).

• Results in ineffectual atrial

contraction, a subsequent decrease in cardiac output, and a loss of atrial kick.

(Afib)

Yes, My parents were Hippies.

If > 100 beats/min then termed RVR or “uncontrolled”.

• Results in ineffectual atrial

contraction, a subsequent decrease in cardiac output, and a loss of atrial kick.

• Patients may develop intra-atrial

emboli from stagnate atrial blood.

• May produce signs & symptoms

that include: lightheadness, palpitations, dyspnea, chest pressure/pain, and hypotension.

Signs & Symptoms

• If stable and RVR, treatment is first

directed toward controlling the ventricular response, rather than converting the dysrhythmia to a sinus rhythm.

• If cardiac function is normal – Calcium

channel blockers or Beta blockers

• If cardiac function is impaired – Digoxin,

Diltiazem, or Amiodarone.

• If severely symptomatic synchronized

cardioversion may be considered.

I have a sister. No, her name is not Venus.

Meet Marvin

We will call him Marvin (Name changed to protect the incent – really for HIPPA)

• 73 year old Male patient
• NKDA
• Weight: 106 kg
• Height: 185 cm
• BSI: ~31
• Presenting for:
• Left Total Hip Replacement

secondary to Osteoarthritis.

Today’s Surgery

I had two dogs as a kid – Phobos and Deimos.

• 15 pack year history –

Stopped smoking 40 years ago.

• Gastric reflux
• Hiatal hernia
• Back pain
• Arthritis
• Hypertension (HTN)
• Depression
• Right total hip replacement in

2008.

• EKG showed NSR.
• CXR had possible paramedian mass or

cardiac enlargement.

• CT obtained, “No mass detected, no

significant abnormality.”

• Cardiac clearance stated: “Low-risk for

cardiovascular complications. No CV symptoms & minimal risk factors. No MI.”

• All Lab studies were within normal

limits.

• Current medications:
• Saw palmetto, calcium, multivitamin,

esomeprazole 40mg AM, and fluoxetine 20mg AM.

• A slightly obese elderly gentleman.
• Lungs were clear to auscultation
• No cardiac murmur or rub was
• noted. RRR.
• Pre-operative vital signs:
• BP 124/82
• HR 80
• RR 18
• SaO2 88% room air
• 94% 2L Nasal Cannula
• T 36.9
• MP II, TMD > 7cm, Positive ULB test,

Full ROM.

Do you know why Phobos and Deimos?

• All Standard monitors were attached
• Patient was preoxygenated for 5

minutes.

• Before induction 2 grams of Ancef IV

were administered.

• Due to the patient’s history of reflux a

standard general anesthesia with a rapid sequence induction (RSI) was preformed.

• For induction:
• 50 mcg Fentanyl
• 60 mg Lidocaine
• 160 mg Propofol and
• 100 mg succinylcholine IV were

administered.

• After loss of eyelid reflex and

fasciculations observed direct laryngoscopy was preformed

• Mac #3 blade used.
• Cormack Grade I visualization.
• Easy atraumatic intubation.
• Cords remained open after

intubation.

• Endotracheal tube placement

was confirmed by positive, equal bilateral breath sounds and positive end-tidal CO2 tracings for 3 consecutive breaths.

• Sevoflurane was titrated to

1.8%.

• The patient was observed to

become tachycardiac.

• A rate in the upper 130’s and an

irregularly irregular rhythm.

• Immediate hypotension was also

noted.

• 100 mcg of phenylephrine 5x.
• Hypotension was moderately improved

but still sub-baseline levels.

• A 12-lead EKG was obtained

that showed new-onset atrial fibrillation with rapid ventricular response

FYI - Phobos and Deimos are the moons of Mars.

• The surgery was cancelled and the

choice was made to emerge patient immediately from anesthesia.

• A smooth atraumatic emergence and

extubation took place.

• No conversion of cardiac rhythm.
• However, Patient now normotensive.
• The patient transferred to PACU.
• Still in A-fib with RVR.
• A cardiac consult was requested and

echocardiogram ordered.

• New on-set atrial fibrillation (AF) is not

uncommon during or after surgery. It may present for the first time during anesthesia and surgery.

• AF is the most common sustained cardiac

dysrhythmia.

• The incidence of AF approximately doubles

with each decade of adult life.

• New onset AF occurs most after:
• Cardiac surgery (10-65%)
• Followed next by thoracic surgery (10-

23%)

• Then non-thoracic surgery (5-10%)
• The waves from this active vary in size,

shape, and timing and this chaotic behavior leads to erratic ventricular contractions that can be greater than 100 beats per minute

• r rapid, as in this case.

How Often?

• The overall mechanisms for AF is

not completely understood and are most likely are multi- factorial.

• Some of the mechanisms that

have been thought to be involved with AF are:

• fibrotic areas in the atrium
• Inflammation
• over-production of catecholamines
• r increased susceptibility to them.
• autonomic imbalance
• electrolyte imbalances and fluid

changes.

Mechanisms?

If a meteorite hits the earth what do you call the ones that miss?

• The literature suggests AF has several risk

factors related to its occurrence.

• The main risk factors include:
• age (> 60yr)
• higher preoperative heart rate( >74

beats/min)

• male gender
• Hypertension
• higher body mass index
• left atrial enlargement
• vascular surgery
• pervious history of atrial fibrillation
• emergency operations
• a history of congestive heart failure
• use of intraoperative transfusion
• renal failure
• chronic obstructive pulmonary disease.

• The literature also revealed that AF is

linked to:

• Increased mortality and morbidity
• Increased cost of stay and length of stay.
• Higher ICU admissions.
• The risk of death after new onset AF in

critically ill patients after non-cardiac surgery is 2- to 6-fold higher.

• Patients that developed Atrial fibrillation

have:

• a higher incidence of postoperative pneumonia

and acute respiratory failure

• greater hospital stay
• 30-day mortality.

Complications

• One of the most important anesthesia

implications of AF is the loss of the atrial contribution to ventricular filling,

• r “Atrial kick”.
• may result in a decrease stroke volume of

up to 20 – 30 %.

• This change in cardiac stroke volume can

lead to hemodynamic instability, myocardial ischemia, and hypoxia.

• Long term implications could be

thromboembolic events or strokes due to the formation of thrombi in the atria due to stasis of blood and the development of atrial and/or ventricular Cardiomyopathy.

metiowrongs.

• Treatment of AF is indicated if the

patient is symptomatic, hemodynamically unstable ,and if they develop cardiac ischemia or heart failure.

• Treatment is to restore and sustain

normal sinus rhythm, prevent thromboembolic events, and control ventricular rate.

• This is achieved by use of

antiarrhythmic drug therapy, anticoagulation therapy, cardioversion, pacemaker implantation and/or surgical procedures, like the Maze procedure.

• A three-part approach should be taken by

the anesthesia provider.

• The provider should assess the need for, the

proper timing of, and the appropriate way to restore a sinus rhythm.

• The provider should take steps to guarantee

appropriate control of the ventricular rate while the patient is in atrial fibrillation.

• Thought should also be given to the need for

anticoagulation to prevent embolic stroke.

• If the patient is non-symptomatic and

hemodynamically stable sometimes no intervention is needed as up to two thirds of patients will spontaneous convert to a sinus rhythm in a 24 hour timeframe.

• In this case report new onset AF was witnessed

with induction of anesthesia. It was decided the best plan of action was to cancel surgery and emerge the patient from anesthesia.

• This was chosen to determine if the hypotension

the patient was experiencing was due to the anesthetic or loss of stroke volume due to loss of atrial systole.

• After anesthesia was ended the patient was

hemodynamically stable but still remained in AF with RVR.

• Immediate cardioversion was not indicted

because for being non-symptomatic.

• The attending anesthesiologist also had concerns

if the patient had previous atrial fibrillation periods that had spontaneously converted to sinus rhythm.

• Cardiac consult, full electrolyte panel, and

echocardiogram were ordered immediately upon arrival in the anesthesia recovery area.

• AF occurred even in a “cardiac

cleared” patient. This patient presented with three of the most common risk factors for AF.

• Age > 64
• Male gender
• History of systemic hypertension.
• Although rare, AF can happen in any

surgical patient and the incidence increases with age.

• In this case study, AF was quickly

recognized during induction of anesthesia and appropriate steps were taking to ensure the best treatment and patient outcome as possible.

Any Questions?

1. Stoelting, RK & Dierdorf, SF. Anesthesia and Co-Existing Disease. 4th Ed. Philadelphia, PA: CHURCHILL LIVINGSTONE; 2002: 83. 2. Nathanson MH & Gajraj NM. The peri-operative management of atrial fibrillation. Anesthesia. 1998; 53: 665-676 3. Falk RH. Atrial Fibrillation. N Engl J Med. 2001; 344:1067-78. 4. Christians KK, Wu B, Quebbermann EJ, & Brasel KJ. Postoperative atrial fibrillation in noncardiothoracic surgical patients. The American Journal of Surgery. 2001; 182: 713-715. 5. Brathwaite D, & Weissman C. The New Onset of Atrial Arrhythmias Following Major Noncardiothoracic Surgery is Associated With Increased Mortality. CHEST. 1998; 114:462-468. 6. Salmaan K, Stewart R, Fergusson DA, et al. Treatment of new-onset atrial fibrillation in noncardiac intensive care unit patients: A systematic review of randomized controlled trials. Crit Care Med. 2008; 36 (5): 1620-1624. 7. Echahidi N, Pibarot P , O’Hara G, & Mathieu P. Mechanisms, Prevention, and Treatment of Atrial Fibrillation after Cardiac Surgery. JACC. 2008; 51(8): 793-801. 8. Amar D, Zhang H, Leung DH, Roistacher N, & Kadish AH. Older Age is the Strongest Predictor of Postoperative Atrial Fibrillation. Anesthesiology. 2002; 96: 352-6. 9. Sohn GH, Shin DH, & Byun KM et al. The Incidence of Predictors of Postoperative Atrial Fibrillation after Noncardiothoracic Surgery. Korean Circ J. 2009; 39:100-104.

• 10. Vaporciyan AA, Correa AM, & Rice DC et al. Risk factors associated with atrial fibrillation after noncardiac

thoracic surgery: Analysis of 2588 patients. The Journal of Thoracic and Cardiovascular Surgery. 2004; 127:779-86.

• 11. Mathew JP

, Fontes ML, & Tudor IC et al. A Multicenter Risk Index for Atrial Fibrillation After Cardiac

• Surgery. JAMA. 2004; 291(14): 1720-1729.
• 12. Mayr A, Knotzer H, & Pajk W et al. Risk factors associated with new onset tachyarrhythmias after cardiac

surgery – a retrospective analysis. Acta Anaesthesiol Scand. 2001; 45: 543-549.

• 13. Barash PG, Cullen BF, Stoelting RK, Cahalan MK, & Stock, MC. Clinical Anesthesia. 6th Ed. Philadelphia, PA;

LIPPINCOTT WILLIAMS & WILKINS; 2009: 870