Dysrhythmias -- Sinus Rhythms

Judy A. Bieker

Nursing of Adults & Children III

East Central College

Normal Sinus Rhythm (NSR)

Rate: 60-100

Rhythm: regular R-R interval

P wave:

persent for every QRS & only 1 per QRS

all shaped the same

rate & rhythm same as for QRS

Normal Sinus Rhythm (NSR) cont

PR interval:

0.12-0.20 seconds in length

all the same length

QRS complex:

0.04-0.11 seconds in length

all the same length & shape

each has a P wave before it

Normal Sinus Rhythm (NSR) cont

Interpretation: NSR

indicates that the SA node is 100% pacing and the electical impulse is following the typical conduction pathway

any rhythm that doesn’t meet this criteria is considered a dysrhythmia

When dysrhythmias are identified

assess the patient

color, mentation, pulse, BP, RR, symptoms

may need a 12-lead EKG

check patient hx

determine need to call MD / initiate protocol

continue to monitor the patient

Sinus bradycardia

seen in healthy young athletes

occurs in response to severe pain, carotid massage, hypothermia, increased intracranial pressure, hypothyroidism, & within the 1st hrs S/P inferior MI

Sinus bradycardia (cont)

Rate: < 60 (but usually not less than 40)

Rhythm: reg

P wave:

persent for every QRS & only 1 per QRS

all shaped the same

rate & rhythm same as for QRS

Sinus bradycardia (cont)

PR interval:

0.12-0.20 seconds in length

all the same length

QRS complex:

0.04-0.11 seconds in length

all the same length & shape

each has a P wave before it

Sinus bradycardia (cont)

Interpretation: Sinus bradycadia

the SA node is firing at a rate less than 60

asymptomatic -

symptomatic -

treat the cause / precipitating factors

atropine / isuprel / pacemaker

Sinus tachycardia

caused by increaseing automaticity due to SNS stimulation

examples include: situations, diseases / conditions, drugs

Sinus tachycardia (cont)

Rate: 100 - 160

Rhythm: reg

P wave:

same shape

precedes each QRS & each is followed by a QRS

rate & rhythm same as QRS

Sinus tachycardia (cont)

PR interval:

0.12-0.20 seconds in length

all the same length

QRS complex:

typical shape & normal length (0.04-0.11)

each has a P wave before it but the T - P interval is shortened with the P wave possible superimposed in the T wave

Sinus tachycardia (cont)

Interpretation: ST

the conduction pathway is the same as NSR but the SA node is discharging at a rate greater than 100 bpm

Treatment

tx the cause

beta-blockers

Sinus Arrhythmia

a speeding up & slowing of the rhythm occurring with respirations

commonly seen in kids & young adults or pt with resp problems

Sinus Arrhythmia (cont)

Rate: (50) 60 - 100

Rhythm: irreg

P wave:

same shape, before each QRS & each has a QRS after it

same rate & rhythm as QRS

Sinus Arrhythmia (cont)

PR interval:

normal length & constant (all the same length)

QRS complex:

0.04-0.11 seconds in length

all the same length & shape

each has a P wave before it

Sinus Arrhythmia (cont)

Interpretation: SA

conduction pathways are the same as NSR but the SA node discharges impulses at an irreg rate in relation to the resp cycle

Treatment

none & continue to observe

Questions about Sinus Rhythms before we each practice?