Abstract
Purpose::
To describe a technique of combined oral chloral hydrate and anterior subtenons anaesthesia for the treatment of threshold ROP.
Methods::
The procedure is carried out within a neonatal intensive care setting. Cyclopentolate 0.5% and phenylephrine 2.5% eye drops are given topically 60 and 30 minutes before, along with chloral hydrate (50mg/kg) orally 60 minutes before. The conjunctiva is grasped with Moorfields forceps in a radial fashion approximately 2mm from the limbus in the inferotemporal quadrant and a small incision is made into subtenons space with Westcott scissors. A 26G blunt curved lacrimal cannula attached to a 2ml syringe containing 1% lignocaine is inserted into subtenons space and advanced nasally parallel to the limbus for about five to six clock hours. Approximately 0.25ml of lignocaine 1% is injected before removing the cannula, reinserting it in a similar manner directed temporally and a further 0.25 ml injected.Peripheral retinal laser photocoagulation is performed using a binocular indirect diode or argon laser and a 28D lens to produce a moderate white retinal reaction.
Results::
Ten eyes of five patients have been treated with this method. In all cases, the planned treatment was delivered. Ocular complications observed at the time of treatment include chemosis and subconjunctival haemorrhage. Only one patient had 2 transient bradycardias at the time of treatment, but these did not occur whilst laser was being applied. There was some head mobility during the procedure, but this did not appear to interfere significantly with the delivery of the treatment. The average duration of treatment was 100 minutes.
Conclusions::
We describe a technique of combined oral chloral hydrate and anterior subtenons anaesthesia, which has been used in this unit successfully. The technique is simple, effective, avoids the risks and logistics of general anaesthesia, while providing superior anaesthesia to topical agents alone.
Keywords: retinopathy of prematurity