The Incidence of Recurrent Laryngeal
Nerve Damage Following an Anterior
Cervical Spine Operation
By:
Brian Purcell, BSN, SRNA
UPMC Hamot Medical Center
School of Anesthesia/Gannon
University
Recurrent Laryngeal Nerve
Recurrent Laryngeal Nerve
• Branch of the Vagus Nerve, Crainial Nerve X.
• Left recurrent laryngeal nerve passes at aortic
arch.
• Provides sensory innervation to infraglottis
(Trachea below the vocal cords)
• Provides motor innervation to all of the larynx
except the cricothyroid muscle
Recurrent Laryngeal Nerve
• Innervates all of the 1st set of Intrinsic Larynx
Muscles. These muscles alter the size and shape
of the larynx.
– Aryepiglottic- Pulls epiglottis down over larynx
– Thyroepiglottic- Assists pulling epiglottis down
– Oblique arytenoid- Pulls arytenoids together
Recurrent Laryngeal Nerve
• Innervates all of the 2nd set of intrinsic laryngeal
muscles except the cricothyroid (External
Superior Laryngeal Nerve)
• These muscles move the true vocal folds
– Thyroarytenoid- relaxes vocal cords
– Lateral Cricoarytenoid- adducts vocal cords
– Posterior Cricoarytenoid- abducts vocal cords
– Traverse Arytenoid- adducts vocal cords
– Vocalis- weak abduction of vocal cords
Recurrent Laryngeal Nerve
• Stimulation of Recurrent Laryngeal Nerve causes
abduction, opening of the vocal cords.
Recurrent Laryngeal Nerve
• Damage to Recurrent Laryngeal Nerve causes
vocal cord adduction, closing.
Recurrent Laryngeal Nerve
• Partial damage to Recurrent Laryngeal nerve on
one side will cause the cord on the same side to
shut, resulting in a deterioration of voice quality
• Unilateral damage usually does not compromise
airway function, but airway protection against
aspiration may be compromised.
Recurrent Laryngeal Nerve
• Bilateral damage to Recurrent Laryngeal Nerve
will cause both vocal cords to shut. This results in
stridor and respiratory distress.
• If the recurrent laryngeal nerve is completely
severed, the vocal cords will partially close and
will not move.
Recurrent Laryngeal Nerve
• Symptoms of Recurrent Laryngeal Nerve damage
– Unilateral: Hoarseness
– Bilateral acute: Stridor, respiratory distress
– Bilateral chronic: Aphonia
Damage to Recurrent Laryngeal
Nerve
• What can cause damage to the Recurrent
Laryngeal Nerve?
– Laryngoscopy
– Intubation
– LMA
– Lesions
– Trauma
– Surgical Procedures
Examples of Surgical Procedures
that can Cause Damage to
Recurrent Laryngeal Nerve
• ENT
– THYROID
– PARATHYROID
– TRACHEAL RESECTION
– NECK DISSECTION
Examples of Surgical Procedures
that can Cause Damage to
Recurrent Laryngeal Nerve
• Thoracic
– Lobectomy
– Pneumonectomy
– Lung Resection
– Mediastinoscopy
Examples of Surgical Procedures
that can Damage Recurrent
Laryngeal Nerve
• Vascular Surgery
– Carotid Endartectomy
Examples of Surgical Procedures
that can Cause Damage to
Recurrent Laryngeal Nerve
• General Surgery
– Esophagostomy/Esophagectomy
– Esophageal Diverticulectomy
Examples of Surgical Procedures that
can Cause Damage to Recurrent
Laryngeal Nerve
• Neurosurgery
– Anterior Cervical Fusion
• Involves anterior neck dissection and retraction of the soft
tissue that gives exposure to the anterior vertebral column.
Anterior Cervical Spine Surgery
and Recurrent Laryngeal Nerve
Damage
• Retraction Injury
– For this surgery, Jaffe and Samuels report a 5%
incidence.
– The exact cause recurrent laryngeal nerve injury is
not known, but it is hypothesized that compression
of the recurrent laryngeal nerve within the
endolarynx leads to injury(Apfelbaum, Kriskovich &
Haller, 2000)
Anterior Cervical Spine Surgery and
Recurrent Laryngeal Nerve Damage
• What can be done to decrease or prevent the
incidence?
– Manipulate ETT cuff after retractor placement
– Use the least amount of air possible in the ETT cuff to
maintain a seal
– Side of surgical approach
– Replace Retractors
– Monitor Recurrent laryngeal nerve during surgery
Manipulate ETT cuff after
retractor insertion
• Apfelbaum, Kriskovich & Haller in 2000 studied
the relationship between deflating cuff after
retractor placement and re-inflating after 5
seconds. Allows ET tube to re-center within the
larynx
• The rate of temporary paralysis decreased from
6.4% to 1.69% using the described maneuver
Manipulate ETT cuff after
retractor insertion
• Audu, et al. in 2006 did not find statistical
significance in their study as to the use of the
above described method.
• Some surgeons use the method some do not
Use just the amount of air
required to create a seal in the
Endotracheal tube cuff
• Audu, et al describe this method as the “just
seal” method.
– the ETT was insufflated using the “just seal” method
as follows: With the ETT cuff deflated, positive
pressure (20–25 cm H2O) was generated in the
breathing circuit while listening for an air leak around
the ETT. The cuff was then insufflated with air until
the leak was obliterated.
Use just the amount of air required
to create a seal in the Endotracheal
tube cuff
• Audu et al in 2006 did not find statistical
significance in decreasing incidence of vocal cord
paralysis associated with recurrent laryngeal
nerve damage
• Jung and Schramm published in 2010 did find
significance in in decreased incidence of paralysis
with lower ETT cuff pressures
Side of surgical approach
• Jung and Schramm (2010) report that in
conjunction with maintaining low ETT cuff
pressures, the left side approach reduced the
incidence of vocal cord paralysis
Replace Retractors
• Rackesh et al. (2010) conducted a study that
found cuff pressure in general may be the cause
of vocal cord paralysis.
• Conclusions were to create a “just seal” and
possibly institute intermittent release of the
retractors which would keep the cuff pressures at
an acceptable level
Monitor Recurrent Laryngeal
Nerve Intra-operatively
• Tisdall, M., Henn, C., & Dorward, N. (2010)
study on 19 patients using vagal/recurrent
laryngeal nerve stimulation to monitor the
integrity of the recurrent laryngeal nerve.
• With small sample size, researchers
concluded that intraoperative monitoring may
potentially reduce the incidence of recurrent
laryngeal nerve palsy.
Monitor Recurrent Laryngeal Nerve
Intra-operatively
Monitor Recurrent Laryngeal Nerve
Intra-operatively
• Stimulation monitoring similar to that used in
Thyroid surgery, where such monitoring is
manditory
• Monitoring identifies the recurrent laryngeal
nerve, and can identify areas of concern which
can be avoided to reduce recurrent laryngeal
nerve injury
• Tisdall, M., Henn, C., & Dorward, N. (2010)
Conclusions
• Recurrent Laryngeal Nerve is Branch of Cranial
Nerve X (Vagus Nerve)
• Left recurrent laryngeal nerve passes at the
aortic arch
• Provides sensory innervation to infraglottis
(Trachea below the vocal cords)
• Provides motor innervation to all of the larynx
except the cricothyroid muscle
Conclusions
• Stimulation of Recurrent Laryngeal Nerve causes
abduction, opening of the vocal cords.
• Damage to Recurrent Laryngeal Nerve causes
vocal cord adduction, closing.
• Unilateral damage causes vocal cord on same
side as the damage to close. This can result in
hoarseness and the inability to protect against
aspiration.
Conclusions
• Bilateral damage will cause both cords to close
and will result in respiratory distress
• Damage to recurrent laryngeal nerve during
anterior cervical surgery is thought to be caused
by compression of the caused by retractor
placement.
• Recurrent laryngeal nerve damage is the most
common ENT complication associated with
anterior cervical procedures.
Conclusions
• Methods of preventing recurrent laryngeal nerve
injury:
• Manipulate the endotracheal tube cuff after
retractor placement.
• Create a “just seal” with ETT cuff
• Possibly perform surgery from left side.
• Stimulation monitoring of recurrent laryngeal
nerve
Conclusions
• Still no concrete standard of care in preventing
recurrent laryngeal nerve damage.
• More study and research needs to be completed
to create a concrete standard of care.
References
• Apfelbaum, R., Kriskovich, M., & Haller, J. (2000).
On the incidence, cause, and prevention of
recurrent laryngeal nerve palsies during anterior
cervical spine surgery. Spine, 25(22), 2906-2912.
• Audu, P., Artz, G., Scheid, S., Harrop, J., Albert, T.,
Vaccaro, A., & ... Rosen, M. (2006). Recurrent
laryngeal nerve palsy after anterior cervical spine
surgery: the impact of endotracheal tube cuff
deflation, reinflation, and pressure adjustment.
Anesthesiology, 105(5), 898-901.
References
• Jaffe, R., & Samuels, S. (2009). Anesthesiologist's
manual of surgical procedures. (4th ed.).
Philadelphia: Lippincott, Williams & Wilkins, a
Wolters Kluwer business.
• Jung, A., & Schramm, J. (2010). How to Reduce
Recurrent Laryngeal Nerve Palsy in Anterior
Cervical Spine Surgery: A Prospective
Observational Study. Neurosurgery (67)1, 10-15
References
• Rakesh, G., Girija,R., Parmod, B., Hemansh, P.,
Manish, M. (2010). Clinical Investigation Effects of
Retractor Application on Cuff Pressure and Vocal
Cord Function in Patients Undergoing Anterior
Cervical Discectomy and Fusion. Indian Journal of
Anaesthesia (54)4, 292-295. DOI: 10.4103/00195049.68370
• Tisdall, M., Henn, C., & Dorward, N. (2010).
Intra-operative Recurrent Laryngeal Nerve
Stimulation During Anterior Cervical
Discectomy: A Simple and Effective Technique.
British Journal of Neurosurgery (24)1, 77-79.
DOI: 10.3109/02688690903398459