International Journal of Anesthesiology & Research, 2013 © 12
Karvandian K, Shabaani S, Naseri S, Mireskandari S M (2013) Retrograde Laryngeal Block: A New Technique for Awake Intubation Compared With Conventional Regional Airway
Block. Int J Anesth Res.1(2), 12-14
International Journal of Anesthesiology & Research (IJAR)
ISSN 2332-2780
Retrograde Laryngeal Block: A New Technique for Awake Intubation Compared With Conventional
Regional Airway Block
Research Article
Karvandian K
1*
, Shabaani S
2
, Naseri S
2
, Mireskandari S M
1
1
Associated Professor, Anesthesiology Department, Tehran University of Medical Sciences Tehran, Iran.
2
Resident in training, Anesthesiology Department, Tehran University of Medical Sciences Tehran, Iran.
*Corresponding Author:
Kasra Karvandian,
Associated Professor, Anesthesiology Department, Tehran University of
Medical Sciences Tehran, Iran.
E-mail: kassramail@yahoo.com
Received: July 27, 2013
Accepted: August 26, 2013
Published: August 28, 2013
Citation: Karvandian K, Shabaani S, Naseri S, Mireskandari S M (2013)
Retrograde Laryngeal Block: A New Technique for Awake Intubation
Compared With Conventional Regional Airway Block. Int J Anesth Res.
1(2), 12-14.
Copyright: © 2013 Kasra Karvandian. This is an open-access article
distributed under the terms of the Creative Commons Attribution Li-
cense, which permits unrestricted use, distribution and reproduction in
any medium, provided the original author and source are credited.
Introduction
Airway management of patients with predicted dificult airway
remains a challenge for the anesthesiologist. The standard ap-
proach for these situations is awake tracheal intubation [1-4].
Awake intubation is a safer method than induction of anesthesia
with intravenous anesthetics and neuromuscular blockers but it
requires more time and experience [2-6]. Predicted dificult airway
is present in patients with anatomic abnormalities like congeni-
tal syndromes or pathologic situations like burn. Other possibili-
ties of dificult airway include pathologies of base of the tongue,
limitation of mouth opening, and great grades of Mallampati [7-
8]. In the case of predicted dificult airway the safest method is
keeping the patient on spontaneous ventilation while attempting
to intubate the patient [6-8]. In order to perform awake intuba-
tion we need to provide adequate topical airway anesthesia avoid-
ing undesirable sympathetic and parasympathetic outlow which
would cause excessive salivation, gag and cough relexes, these
responses make intubation dificult [8-18]. Regional airway block
is used to perform direct laryngoscopy and intubation, lexible
iberoptic laryngoscopy, and diagnostic bronchoscopy [16-20].
Translaryngeal tracheal block, bilateral superior laryngeal nerve
and glossopharyngeal nerve blocks beside topical anesthesia of
the oral mucosa is the conventional method for this purpose
which provides satisfactory regional anesthesia of airway with
excellent eficacy [18-19]. Retrograde laryngeal block is a new
method of regional airway anesthesia, which provides complete
airway analgesia. In this method airway block is done by insert-
ing a catheter from cricothyroid membrane over a gide wire, after
applying topical anesthesia. The catheter has three lumens with
three distinct oriices, each is located either in supraglottic area,
glottis or subglottic area. By administration of local anesthetic
from the catheter all these regions will be anesthetized completely.
Abstract
Introduction: Retrograde laryngeal block is a new technique that blocks complete supraglottic and glottic area by introducing cath-
eter retrograde from trachea to these regions.
Methods and Materials: This is a clinical trial conducted on two groups each containing 15 patients, who were candidate for awake
intubation. The irst group (A) underwent conventional method of airway block, by multiple injections of local anesthetic. The
second group (B) underwent retrograde laryngeal block as a new method of regional airway anesthesia. In this method the catheter is
inserted from cricothyriod membrane through a lexible guide wire, and then local anesthetic drug will be administered by direct vi-
sion of tip of the catheter by employing glide scope. The catheter has three separate oriices; each will stay on distinct area of either
supraglottic and glottis area which can be adjusted at any level through this area that is considered to be blocked.
Result: Both groups had hemodynamic stability during performing block. In group A we had two incidences of laryngospasm
due to pain of multiple needle insertion; in group B we had no incidence of laryngospasm (P=0.1). In group A we had 5 patients
with partial airway block which needed further intervention during awake intubation but in group B all the cases had complete and
perfect airway block (P=0.001). Patients comfort was better in group B with single injection than group A with multiple injections
(P=0.005).
Discusion: The advantage of this method is single injection and high quality of block performance in comparison with the other
technique. It can be conducted for the patients with neck pathologies that make conventional airway block impossible.
Conclussion: This method can be applied in patients with neck pathologies that make conventional block impossible.
Key Words: Retrograde; Block; Airway; Catheter; Cricothyriod Membrane.