الفهرس 
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Abstract
Pressor effects of laryngoscopy and tracheal intubatioi (II) are due
to reflex sympatho-adrenal discharge provoked by epil ryngeal and
laryngotracheal stimulation subsequent to laryngoscopy aJ d II, which
results in hypertension, tachycardia, arrhythmia and a chat ~e in plasma
catecholamine concentrations leading to a decrease in the I It ventricular
ejection fraction (stroke volumelend-diastolic volume) ane ST-segment
changes that indicate myocardial ischaemia. These resp ases can be
problematic to patients suffering from cardio-vascular, ce :bro-vascular
or abdomino-vascular disease in which hypertension .an lead to
haemorrhage.
Sympathetic stimulation from TI also increases the I :P which can
be harmful iII patients with intracranial mass lesions or . icreased ICP
from other pathology, and increases lOP which is dangerc IS in patients
with impending perforation of eye, perforating eye injuries, nd glaucoma.
Control of lOP during ophthalmic surgery or diagnostic tonometry is
clinically important, because airway manipulation may , orsen ocular
morbidity or produce misleading results.
Many attempts have been made to attenuate the pre sor effects of
laryngoscopy and II including drugs as: General anaesth tics like: (IV
thiopentone, propofol, N20 inhalation in oxygen and N20 I halation with
propofol infusion), local anaesthetics like: (IV, nebulizer and tracheal
lidocaine and nebulized bupivacaine), IV opioids lie: (fentanyl,
alfentanil, sufentanil, remifentanil, buprenorphine ar 1 tramadol),
selective P-I adrenoceptor blockers like: (IV esmolol), Cl cium channel
blockers like (sublingual nifedipine, IV verapamil and IV iltiazem), a-2
adrenoceptor agonists like: (oral and IV clonid ie and IV
dexmedetomidine) and vasodilators like: (IV sodium nit! ,prusside, IV,
topical and intranasal nitroglycerin and isosorbid dinitrate t :rosol into the
buccal mucosa)
The pressor response to fiberoptic orotracheal intub tion is similar
to orotracheal intubation facilitated by the Macintosh laryng scopy blade.
The intubating stylet is used during rapid sequence intubations or
whenever the haemodynamically stressful time of laryng scopy is best
minimized (e.g., cardiac anaesthesia or neuroanaesthesia).
Lightwand intubation, which does not require a 1: yngoscope to
elevate the epiglottis, has shown faster times to int bation, fewer
intubation attempts and less trauma than direct lary goscopy, and
significantly attenuates the pressor resonse to TI in normo msive patients
and also during awake TI. LW intubation is more effective than fibreoptic
intubation in attenuating the pressor response to TI u normotensive
elderly patients, however, in hypertensive elderly patier s; there is no
difference between the two techniques. Both devices sre useful for
intubation in hypertensive elderly patients because the RP . is maintained
within acceptable limits with both devices.
The LMA offers a safer and more effective option 1 IanTI because
it rarely requires direct laryngoscopy, clearly decreasiJ: : this type of
trauma and it is one major reason for the observed attl mated pressor
responses to LMA. The ll-MA attenuates the haemo iynamic stress
response to TI compared with the Macintosh laryngoscope.
The c:uffed oropharyngeal airway (COPA) causes ess pharyngeal
trauma thalli the LMA and is associated with smaller cardiovascular
changes after airway insertion compared with the LMA.
Superior laryngeal n. and glossopharyngeal n. b icks are also
’effective methods in blunting adverse haemodynamic resp nses. Superior
laryngeal n. block is appropriate for patient requir 19 TI before
anaesthetic induction and glossopharyngeal n. block c n be used in
patients who need atraumatic, sedated, spontaneou y ventilating,
”awake” TI.