Author Information
Patil YS*, Wajekar AS**,
Patel RD***, Samant PY****.
(* Associate Professor, ** Assistant Professor, *** Professor, Department of Anesthesiology; **** Additional
Professor, Department of Obstetrics and Gynecology, Seth G S Medical College
& KEM Hospital, Mumbai, India.)
Abstract
We present the anesthesia management of a pregnant patient with
acquired subglottic stenosis for elective lower segment caesarean
section (LSCS) under spinal anesthesia with severe postoperative
desaturation requiring emergency intubation and tracheal dilatation.
Presence of tracheal stenosis during pregnancy significantly affects
maternal and foetal oxygenation and ventilation making anesthesia
management very challenging. Congestion and edema of the airway in
pregnant patients combined with increased respiratory load can worsen
the obstruction in such patients. The goals of anesthesia are
avoiding maternal loss of airway, maintaining both maternal and fetal
oxygenation and ventilation. Although the surgery was successfully
managed with neuraxial anesthesia, the patient still remained at high
risk of postoperative complications. Emergency airway management may
be required at any stage in such patients and preparation for
difficult airway should include keeping bronchoscopy, bougie and
tracheal dilators, jet ventilation and tracheostomy ready. In some
scenarios, femoro-femoral cardiopulmonary bypass may also be
required.
Introduction
Pregnancy is considered
as difficult airway and failed
intubation can give rise to catastrophic consequences. Presence of tracheal
stenosis during pregnancy significantly affects maternal and foetal oxygenation
and ventilation making anesthesia management very challenging.[1–3] Post intubation tracheal stenosis affects 4-13% of adults
in United States and 90% of them progress to chronic subglottic stenosis.[4]
We present the
perioperative anesthesia management of a pregnant patient with acquired
subglottic stenosis for elective lower segment cesarean section (LSCS).
Although the surgery was conducted under combined spinal epidural anesthesia,
she had postoperative severe hypoxia necessitating emergency intubation and
tracheal dilatation.
Case Report
A 24 year old
primigravida with history of tracheal stenosis was posted for elective LSCS in
view of cephalopelvic disproportion. During first trimester, she contracted
pneumonia and acute respiratory distress necessitating endotracheal intubation
for 8 days. 15days later she developed acute stridor. Flexible bronchoscopy
done by ear-nose-throat (ENT) surgeons, at the time and again 3 months later
showed grade III soft tracheal stenosis near 5th tracheal ring with
tracheal lumen of 0.5 cm which required tracheal dilatation with bougie. Elective
tracheostomy was avoided since it was a soft stenosis responsive to tracheal
dilatation. Currently, she had inspiratory stridor which increased in supine
position and with effort tolerance of one flight. Her haemoglobin was 9.1 g%.
All other routine investigations were normal. Standard monitors including
electrocardiography, automated blood pressure, pulse oximetry (SPO2) and
end-tidal carbon dioxide were applied. Her pulse was 42/min with blood pressure
130/70 mm hg and SPO2 98%. Left uterine displacement was maintained. Combined
spinal epidural (CSE) anesthesia was planned. ENT surgeon was present in the
operating room throughout procedure. Difficult airway preparation included
laryngeal mask airways (LMA) and different sizes of endotracheal tubes, Frova’s
ventilating and intubating bougie, transtracheal jet ventilation, rigid
bronchoscope with tracheal dilators of various sizes and tracheostomy tubes.
Epidural catheter was inserted at L2-3 space and bupivacaine 0.5% 2cc was
injected intrathecally in L3-4 space with a 25G spinal needle. T6 level was
achieved. A healthy neonate with a good APGAR score was delivered. The
intraoperative period was uneventful. No other sedatives were given. Post
procedure 30mg tramadol diluted in 10cc was injected epidurally. Paracetamol 1g
IV was given 8hrly. She was shifted to recovery room with oxygen by mask.
Four hours after
surgery, she had hypotension up to 80/60 mm hg and desaturation up to 88%.
Ventimask with reservoir bag at 8L/min brought her saturation up to 92%. Two packed cell transfused since she appeared
pale and blood loss was around 900ml. She was shifted to intensive care unit
(ICU) in propped up position. She maintained 100% saturation with overnight
continuous positive pressure ventilation. After chest physiotherapy in ICU, she
probably had loosened secretion which obstructed the stenotic airway and she
suddenly desaturated up to 67% with peripheral cyanosis. She was intubated with
5.5mm endotracheal tube. Her arterial blood gases 1 hour later were pH 7.098,
pCO2 83.7, pO2 161.9, HCO3 18.3 and Sao2 98.4%. Emergency bronchoscopy and
tracheal dilation under intermittent apneic technique with jet ventilaton under
total intravenous anesthesia (TIVA) was done. After successfully dilating with
26 size tracheal bougie, she was intubated with 7mm endotracheal tube. She was
electively ventilated and weaned off and extubated after 12 hours. She was
shifted to ward on day 3 and discharged on day 8.
Discussion
Difficult intubation can
lead to significant airway related injuries leading to adverse maternal and
fetal outcomes.[5] Congestion and edema of the airway in pregnant patients
combined with increased respiratory load can worsen the obstruction in such
patients.[1] Mother and foetus are at high risk of impaired oxygenation
and ventilation. Definitive treatment with stents for tracheal stenosis are
licensed only for malignant conditions.[1,6] Surgical morbidity and mortality associated with tracheal
reconstruction prevents its use in benign stenosis. Generally such tracheal
stenosis are managed with serial tracheal dilatations. Radiological evaluation
with computed tomography or lateral neck x-ray was avoided in our patient due
to her pregnancy and as prior bronchoscopy reports were available.
The goals of anesthesia
are avoiding maternal loss of airway, maintaining both maternal and foetal
oxygenation and ventilation. Preoperative bradycardia in the supine position
can be attributed to inferior vena cava compression, relieved by left uterine
displacement. Although the surgery was successfully managed with neuraxial
anesthesia, patient still remained at high risk of postoperative complications.
As occurred in our patient, any kind of airway irritation such as coughing or
instrumentation can precipitate catastrophic complete airway obstruction.[6] Ventilation through 5.5 mm endotracheal tube led to severe
hypercarbia and emergency tracheal dilatation with bronchoscopic passage of a
large size tube was required under TIVA.
Common causes of
tracheal stenosis are inflammatory diseases, benign and malignant tumours,
collagen vascular diseases etc. Prolonged intubation is one of the leading
causes of acquired tracheal stenosis with incidence of almost 4-13% intubated
adults.[4] The tracheal wall in contact with the endotracheal cuff is
generally the site of this stenosis.[6] Local inflammation and mucosal ischaemia near cuff leads to ulceration, granulation tissue,
tracheal chondritis and fibrotic stenosis.[5] The site of tracheal
stenosis is very important since upper stenosis may be treated with an
endotracheal tube passed beyond the cords. But mid-level tracheal stenosis may
require unilateral or differential bronchial intubation or even cardiopulmonary
bypass.[6]
If surgery demands, then
elective intubation can be attempted in topical airway anesthesia or bilateral
cervical plexus block.[6,7] Salama et al reported a case of pregnant woman with
tracheal stenosis whose stenotic area was preoperatively dilated by a balloon
with fibre optic bronchoscopy under local anesthesia.[2] Kuczkowski et al performed preoperative elective
tracheostomy under local anesthesia in the 36th week of pregnancy which was
kept till the end of her pregnancy.[8] We did not perform elective tracheostomy in our patient,
because ENT surgeons felt she can undergo tracheal dilatation if need arises.
Parsa et al and Sutcliffe et al described the general anesthesia management for
bronchoscopic dilatation of stenotic airway in pregnancy.[1,3] Laryngeal mask airway is a valuable tool for ventilation
and passing a guidewire, allowing flexible bronchoscopy.[6]
Conclusion : Airway
management of pregnant patients with critical tracheal stenosis can be tricky
and the key step is prevention of loss of airway, maintenance of adequate
oxygenation and ventilation. Although regional anesthesia is a boon in such
patients for conduct of anesthesia, need for emergency airway management must
be kept in mind. Multidisciplinary approach along with availability of
experienced personnel and difficult airway equipments at hand ensures
successful outcome.
References
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- Sutcliffe N, Remington SAM, Ramsby TM, Mason C. Severe tracheal stenosis and operative delivery. Anaesthesia 1995;50(1):26–9.
- McCaffrey T V. Classification of laryngotracheal stenosis. In: Laryngoscope. 1992. page 1335–40.
- Zarogoulidis P, Kontakiotis T, Tsakiridis K, Karanikas M, Simoglou C, Porpodis K, et al. Difficult airway and difficult intubation in postintubation tracheal stenosis: A case report and literature review. Ther Clin Risk Manag 2012;8:279–86.
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- Cho A-R, Kim H-K, Lee E-A, Lee D-H. Airway management in a patient with severe tracheal stenosis: bilateral superficial cervical plexus block with dexmedetomidine sedation. J Anesth [Internet] 2014;29(2):292–4. Available from: http://link.springer.com/10.1007/s00540-014-1912-9
- Kuczkowski KM, Benumof JL. Subglottic tracheal stenosis in pregnancy: Anaesthetic implications. Anaesth Intensive Care 2003;31(5):576–7.
Patil YS, Wajekar AS,
Patel RD, Samant PY. Tracheal Stenosis In Pregnancy : Anesthetic Dilemma. JPGO
2015. Volume 2 No. 8. Available from: http://www.jpgo.org/2015/08/tracheal-stenosis-in-pregnancy.html