Anasthesia For Adult Bronchoscopy, A Report

[Aljubouri83]

Anaesthesia For Adult Bronchoscopy


Anaesthetic Considerations :
Anaesthetic techniques & airway management depend entirely on the site & size of the lesion & the type of the procedure proposed. It is a sound principle to maintain spontaneous ventilation in patients with upper airway obstruction.

Pre-Operative Assessment :
Frequently, patients for bronchoscopy have co-existing pathology which may influence their response to anaesthesia & surgery. Those with smoking related chest diseases are likely to suffer from ischemic heart diseases, the risk of which must be assessed before embarking upon bronchoscopy. It is likely also that patient with lung pathology resulting from smoking have parenchymal as well as focal disease under investigation. Patients presenting for emergency bronchoscopy due to massive haemoptysis will require appropriate resuscitation prior to anaesthesia. As with all patients, an assessment should be made of the airway in relation to expected ease of intubation & ventilation.

Premedication :
Premedication for bronchoscopy may help to provide good operating condition, particularly in the conscious patient. Atropine decrease airway secretions & some advocate its use routinely. For patients likely to suffer from bronchospasm, which applies to many in this population, it can be helpful to premedicate with a B2 agonist, aminophylline, & steroids depending on the disease severity. However, some simply given an oral benzodiazepine to provide anxiolysis & day-case patients are not premedicated.

Monitoring :
All patients undergoing anaesthesia should be monitored with pulse oximetry, end-tidal CO2 (if possible), non-invasive blood pressure & ECG.
Depending on the anticipated duration of bronchoscopy & subsequent surgery, arterial pressure can be monitored directly using an arterial canula.
The continuous presence of Anaesthetist is essential.

Patient Position :
Rigid bronchoscopy requires the patient to be positioned with full extension of the neck. & the is most easily achieved by putting a pillow under the patient's shoulders & allowing the head to rest on the operating table.
Passing the rigid scope can be awkward & it is very easy to damage the teeth & most operators will use some form of guard to minimize any injury.
Flexible bronchoscopy is slightly different from & most position patients in "Sniffing the morning air" position, i.e. the neck flexed & the head extended. This allows easier access to the larynx using the flexible scope. If this procedure is carried out on a conscious patient, then the bite block is often used to protect the scope.

Local Anaesthesia Of The Upper Airway :
Flexible fiber optic bronchoscopy is performed often using local anaesthesia alone. It is also possible to perform Rigid bronchoscopy under local anaesthesia but the degree of neck extension required for the examination is considerable & general anaesthesia is more acceptable for both patient & operator.
With general anaesthesia it is still a good idea to provide the airways with local anaesthesia. Bronchoscopy is highly stimulating & requires a deep plain of anaesthesia. Due to vagal afferent reflexes in the airways, bronchoscopy is associated with cardiac arrhythmias in up to 11% of patients.
There are several techniques described to provide local anaesthesia to the upper airways. In general, local anaesthesia must be directed to each area through the bronchoscope must pass i.e. the nose (if using naso-pharyngeal route), pharynx, larynx, & trachea.
Nose : 4% lignocaine spray with adrenaline, cocaine soaked pledgets or introducing progressively larger naso-pharyngeal airways covered with lignocaine jell.
Pharynx : lignocaine spray or gargled, blocking of the lingual branch of the glossopharyngeal nerve (2% of lignocaine 2 ml injected into the trough of the palatoglossal arch on both sides).
Larynx : spraying lignocaine progressively through the suction channel as the bronchoscope is introduced, by superior laryngeal nerve block (2% lignocaine 2 ml injected into the thyroid membrane on each side), or trans-tracheal injection of lignocaine (2% lignocaine 4 ml injected through the cricothyroid membrane).
Trachea : spraying via the bronchoscope or trans-tracheal injection. The intense coughing caused by this injection effectively distributes local anaesthetics to the larynx & lower bronchial tree.

** It is important supplemental O2 during bronchoscope under local anaesthesia. This can be achieved with a single nasal spring.

General Anaesthesia :
Techniques used to provide general anaesthesia for bronchoscopy are many & varied. All patients should receive an adequate period of pre-oxygenation. Anaesthesia should be sufficiently deep to limit the pressor response to bronchoscopy & suppress airway reflexes whilst being readily reversible. The procedure can be very short & the duration of the profound stimulus of the bronchoscopy in the trachea shorter still. Total IV anaesthesia offers flexibility as it can be used with Venturi & ventilation bronchoscopes & will maintain anaesthesia during pauses in ventilation. Intermittent IV doses of anaesthetic agent, opioid & muscle relaxant given in anticipation & in response to passage of the bronchoscopy offers a flexible & responsive technique. Remifentanil by infusion IV is effective in limiting the pressor response to bronchoscopy & allows prompt return of spontaneous ventilation.

Reference :
- S J Gold, D R J Dothie, et al. BMJ, no. 47 July, 1999 & no. 48 September, 1999. Continuing medical education care topic, anaesthesia for adult bronchoscopy.


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Ahmed A. Al-Jubouri

[Dr.Leo1984]

nice try dear


Dr. walid mustafa gave us this topic

[Aljubouri83]

Well, you are really lucky to have the lecture of such famous & intellegent professor, he is the best thoracic surgeon in Iraq ..

They want a report of each student in 5th year about anasthesia here ..
So, I did this ..
I hope you like it ..




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Ahmed A. Al-Jubouri