•
Also ‘carotid bulb’
•
Lat. ‘sinus caroticus’
•
The common carotid
artery dilation just
before its
bifurcation into the
internal and
external carotid
artery
•
Contains numerous
baroreceptors
Measuring the blood pressure
(Possible thanks to stimulating
pressoreceptors present in the artery wall)
Stimulating the carotid sinus in every way,
for example:
◦
manually
◦
during head
rotation (e.g. while
shaving)
◦
by wearing a tight
collar, scarf or…
a clerical collar ;)
Blood pressure changes stimulate the
baroreceptors
The afferent impuls goes to the vagus nerve
nucleus and angiokinetic center in
brainstem
The efferent impuls runs in the vagus nerve
to the sinoatrial and atrioventicular nodes in
the heart
The reflex
The reflex
track scheme
track scheme
Stimulating the carotid sinus causes a blood
pressure increase
Receptors tell the brain about it
The brain: ‘OMG, I need to lower a heart
beating rate!’
The heart beating rate lowers
The blood pressure decreases (even though
it’s normal)
We’re fainting (only when carotid sinus
syndrome = carotid sinus hypersensitivity
occurs)
Brain hypoxia
◦
Dizziness
◦
Faintness
Death (if asystole appears)
Used to diagnose the carotid sinus syncope (faintness) –
the patient faints after the massage
Sometimes useful for differentiating
supraventricular tachycardia (SVT) from ventricular
tachycardia
Less effective than
pharmaceutical
management of SVT
though is still
the preferred first-line
of treatment
Able to steady a
racing heart (SVT)
SVT diagram
Gentle massaging the carotid artery for 5
seconds on one side of a neck whilst monitoring a
heart rhythm and blood pressure
The heart rhythm is monitored via electrodes on
a chest attached to a heart monitor, whilst
the blood pressure is being assessed* via a cuff
around an upper arm
If the test is normal on one side of the neck, it will
probably be repeated on the other side
*assessed – oszacowany
Patient upright for 5 minutes prior to massage
Initiate monitoring EKG, blood pressure, heart rate
Identify carotid sinus location at midpoint between angle of mandible,
superior border of thyroid cartilage
Start with carotid sinus on right side:
◦
Massage location firmly but gently (use same pressure that would
indent tennis ball ; do not apply so much pressure to occlude carotid)
◦
Continue massage for 5 second period
◦
Record findings (symptoms of syncope or presyncope; mark massage
period on EKG; continue EKG until heart rate returns to baseline;
record lowest systolic and diastolic blood pressure - occurs within 15
seconds of massage)
Repeat same procedure for other positions
◦
Repeat baseline monitoring values
◦
Repeat Carotid Sinus Massage of left side
◦
Repeat baseline monitoring values
Observe patient in supine position for 10 minutes
Thank you for your
attention
(if there was any)
Silbernagl S., Despopoulos A., „Ilustrowana fizjologia człowieka”, PZWL,
Warszawa 2010
http://www.bartleby.com/107/Images/large/image513.gif
http://en.wikipedia.org/wiki/Carotid_sinus
http://medical-dictionary.thefreedictionary.com/_/viewer.aspx?
path=dorland&name=sinus_caroticus.jpg
http://www.zgapa.pl/zgapedia/Zatoka_t%C4%99tnicy_szyjnej.html
http://pl.wikipedia.org/wiki/Zatoka_t%C4%99tnicy_szyjnej
http://www.cartoonstock.com/newscartoons/cartoonists/cgo/lowres/cgon466l.jpg
http://upload.wikimedia.org/wikipedia/commons/6/62/Lead_II_rhythm_generated
_sinus_bradycardia.JPG
http://demotywatory.pl/302704/Koloratka
http://www.poradnikmedyczny.pl/mod/archiwum/629_zesp
%C3%B3%C5%82_ciasnego_ko%C5%82nierzyka.html
http://www.interna.com.pl/zespolzatokiszyjnej.htm
http://www.fpnotebook.com/cv/exam/CrtdSnsMsg.htm
http://www.ruh.nhs.uk/gps/services/specialties/older_peoples_unit/documents/c
arotid_sinus_massage_leaflet.pdf