Reda Gomah El Garia (Ophthalmologist) share his
- Patient in a Supine Position
- Ask patient to look
straightforwardto put the Eye in a Primary Position
- An injection of approximately 7 to 10 mLof
anestheticusing a needle measuring 25 to 30 mm in length.
- Define the inferotemporal quadrant
- Displacing the globe from the orbital rim with fingers( index and middle fingers) in order to create space and pass the equator more easily.
- Proceed progressively, with the tip of the needle ( bevel towards the globe) parallel to the orbital floor then redirecting it toward the apex of the cone once u have passed the equator of the globe.
- Interrupted slow injection is highly recommended in 30 to 60 sec duration ( one shot injection is not recommended)
The axial length of the eye is an important consideration when Block is needed
Plz recheck the axial length in both eyes before starting ur scheduled surgery
Axial length > 26 mm has higher risk of perforation
Discuss the surgery with the patient and ask for assistance by staring in the primary position.
If patient’s cooperation is poor, the patient should be sedated prior to proceeding.
Use needles no longer than 30 mm.
If u perceive any resistance to the injection syringe because of hitting the sclera or the orbital floor bone u should stop.
Pay great attention to the angle of incline of the needle with respect to the globe in eyes with an axial length greater than 26 mm.
Never ask the patient to look in a superonasal position as this could bring the sclera or the sheath of the optic nerve closer to the needle inserted in the inferotemporal quadrant
Avoid a second injection of anesthetic unless absolutely necessary
Check the analgesia is adequate by gently pinching the conjunctiva.
Always remember that a retrobulbar injection of just 3 mL of anesthetic causes an increase in IOP approximately 12% to 80% (37 mm Hg) .
Finger massage of the globe (or use of the Honan balloon) for 3 to 5 minutes after the injection to reduce the IOP to baseline in 60% to 80% of cases.