Anesthesia Student Survival Guide.pdf - Index of

Table 16.3 Common intraoperative dysrhythmias.
Problem Differential
diagnosis
Remarks
COMMON INTRAOPERATIVE PROBLEMS ● 255
Bradycardia b-blockers Probably the most common cause.
Hypoxia Occurs with severe hypoxia.
Myocardial infarction Likely if the right coronary artery and sinus node are
involved in the infarction.
Increased vagal tone Surgical stimulus on the gut, bladder, or other
organs may increase vagal tone. Atropine and, later,
deepening anesthesia may be indicated. May also be
seen in athletes.
3rd degree heart block The ECG rhythm strip will provide the diagnosis.
Calcium channel blockers Especially caused by diltiazem (used for this purpose in
atrial fibrillation and flutter).
Reversal of neuromuscular Co-administration of an anticholinergic medication
blockade with
(atropine or glycopyrrolate) is standard practice, so this
cholinesterase inhibitors happens rarely. However, edrophonium may be used
such as edrophonium or alone to try to convert SVT or a slow heart rate, during
neostigmine
testing for myasthenia gravis.
Tachycardia Increased pain or surgical
stimulus
Premature
ventricular
contractions
The most common cause at the start of the surgical
procedure. May suggest insufficient anesthesia.
Vasopressors or inotropes Ephedrine, epinephrine, norepinephrine, isoproterolol
can all cause tachycardia
Myocardial infarction The most common dysrhythmia associated with MI.
Arrhythmias Atrial fibrillation, Ventricular Tachycardia.
Malignant hyperthermia Tachycardia in MH follows an observed increased CO2 production and precedes hyperthermia.
Atropine, scopolamine, These are commonly given as antisialogogues
or glycopyrrolate
(dry secretions), vagolytics (increase heart rate) or
administration
antiemetics (nausea control).
b-adrenergic agonists Bronchodilators, tocolytics, and decongestant
medications may cause tachycardia.
Hypoxia Always consider hypoxia first.
Myocardial ischemia Check a 12-lead when feasible.
Metabolic acidosis/
Should always be high in the differential. Consider
alkalosis
checking a blood gas.
Hypokalemia Patients on diuretic therapy, without potassium
replacement, may have this. Patients on digoxin who
are hypokalemic are at particular risk.
Digoxin Commonly used for atrial dysrhythmia therapy.
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