SYNOPSIS

Rajiv Gandhi University of Health Sciences, Karnataka, Bangalore

“EFFICACY OF HYALURONIDASE VERSUS SODIUM BICARBONATE IN PERIBULBAR ANAESTHESIA”

Name of the candidate : Dr. Sarita R. J. Gonsalves

Guide : Dr. Francis E. A. Rodrigues

Co-Guide :

Course and Subject : M.S. (Ophthalmology)

Department of Ophthalmology

Father Muller Medical College,

Kankanady, Mangalore – 575002.

AUGUST – 2008

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES,

KARNATAKA, BANGALORE.

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1. / NAME OF THE CANDIDATE
AND ADDRESS / DR.SARITA R. J. GONSALVES
DEPT OF OPHTHALMOLOGY
FATHER MULLER MEDICAL COLLEGE
KANKANADY,
MANGALORE- 575002
2. / NAME OF THE INSTITUTION / FATHER MULLER MEDICAL COLLEGE
KANKANADY,
MANGALORE- 575002.
3. / COURSE OF STUDY AND SUBJECT / M.S. OPHTHALMOLOGY
4. / DATE OF ADMISSION TO COURSE / 22-04-2008
5. / TITLE OF THE TOPIC
EFFICACY OF HYALURONIDASE VERSUS SODIUM BICARBONATE IN PERIBULBAR ANAESTHESIA.
6. / BRIEF RESUME OF THE INTENDED WORK
6.1 NEED FOR STUDY
The most ideal prerequisite for an eye surgeon performing surgery under local anaesthesia is to achieve total akinesia,surface anaesthesia and hypotony and favourable visual outcome.Retrobulbar anaesthesia had become the anaesthesia of choice for ocular surgery till recently when a number of complications were attributed to it,therefore peribulbar anaesthesia has been advocated to decrease the complications associated with retrobulbar anaesthesia.
The anaesthesia and akinesia occurs due to sensory and motor blockade,hypotony occurs due to loss of tone of extraocular muscles.
The anaesthetic solution used is 2/ lignocaine and 0.5/ bupivacaine which has to spread by diffusion.
Hyaluronidase was widely used in peribulbar anaesthesia as it caused better absorption of anaesthetic solutions,reducing the time of onset of anaesthesia and bringing about akinesia.Various authors have studied the effect of buffering mixtures of lignocaine,bupivacaine and hyaluronidase.Recently some studies have doubted the efficacy of hyaluronidase in improving the quality of anaesthesia,added to this is the cost factor of the drug,limited shelf life and re usage in the same sitting.risk of anaphylaxis due to its enzyme nature.
Hence the need for studying the efficacy of sodium bicarbonate which is cheap, readily available, because of its basic nature alkalinizes the local anesthetic solution without risk of anaphylaxis and to see if it is an effective alternative to hyaluronidase.
7. / 6.2 REVIEW OF LITERATURE
The quest for a safer anaesthetic technique lead to the description of peribulbar anaesthesia.In 1970 kelman1 described this technique of ophthalmic anaesthesia.Bloomerang2 used periocular anaesthetic technique in 1983 using a combination of pre warmed solution of 2/ lignocaine, 0.5/bupivacaine, hyaluronidase and sodium bicarbonate. 8-10cc was injected slowly inferotemporally until the orbit becomes full.It produced periocular anaesthesia by bulk spread and anaesthesia by blocking the pre septal fibres of the facial nerve..
Davis and Mendel3 with their publication of peribulbar anaesthesia in 1986 first used the term peribulbar anaesthesia.They gave injection of lignocaine along with bupivacaine and hyaluronidase outside the muscle cone of the eye in the infero temporal and supero nasal quadrants and showed good anaesthetic effect,coupled with lack of amaurosis . This was advocated to avoid damage to the optic nerve and other intra conal structures.
The modification of local anaesthetics by addition of sodium bicarbonate has been studied for a long time..Lewis P,Hamilton R C,Loken R J,Malty J R,,Strunin L4 conducted one such study in 1992 in which he used plain and ph adjusted 0.75\ bupivaicaine .Hyaluronidase was added to both solutions prior to the block.The onset of anaesthesia was shortened with alkalinisation but the number of supplementary injections in ph adjusted solution was increased.
Roberts E J,Macleod A B,Hollans H5 in 1993 determined the effectiveness of various combinations of lignocaine,epinephrine and hyaluronidase with bupivacaine. With or without alkalinization.All patients were given 9ml peribulbar block by the same surgeon and a graded assessment of analgesia and anaesthesia made one hour later.a mixture using all the agents gave a significantly better result.
srinivasan M,Vamshidhar M,Gopal R,Banushree6 has also compared the effect of hyaluronidase and sodium bicarbonate in ocular anaesthesia and proved that alkalinisation of local anesthetic could be and effective alternative in terms of efficacy to hyaluronidase.
AIMS & OBJECTIVES
1)  To determine the efficacy of sodium bicarbonate as an alternative to hyaluronidase in peribulbar anaesthesia in terms of:
a)  time of onset
b)  anaesthesia and akinesia achieved
c)  effectiveness
d)  duration of action
2)  To determine the visual outcome in the two groups of patients after 8 weeks of post operative period.
3)  Compare the side effects and toxicity observed with both the drugs.
MATERIALS & METHODS
7.1 SOURCE OF THE DATA
Patients (maintaining inclusion & exclusion criteria) admitted at Father Muller Medical College & Hospital in the ophthalmology department
7.2 METHODS OF COLLECTION OF DATA
Study Type: Comparative Study.
Duration of Study: One year.
Sample Size: Hundred patients (selected using purposive sampling technique), who will undergo cataract surgery under peribulbar block with local anaesthetic buffered with either sodium bicarbonate or hyaluronidase in one eye will be included in the study. Data will be collected using a proforma.
These hundred patients will be categorized as follows:
Group A : 50 who will undergo cataract surgery with anaesthesia with sodium bicarbonate buffered local anaesthetic solution of 2/ lignocaine and 0.5/ bupivacaine.
Group B : 50 who will undergo cataract surgery with anaesthesia with hyaluronidase mixed local anaesthetic solution of 2/ lignocaine and 0.5/ bupivacaine.
Patients will be assigned randomly to either Group A or Group B
PREOPERATIVE ASSESSMENT:
Patients will be admitted one day before surgery. Detailed history will be taken from each patient. History regarding allergy to any drug will be elicited. General and systemic examination will be done to rule out associated illness complete ophthalmological examination will be done which includes patient’s visual acuity assessment and retinoscopy .
Anterior Segment examination, Fundus examination and assessment of Intraocular Pressure and Patency of the lacrimal system will be done using standard procedures.routine investigations for surgical fitness will be carried out.
A systemic and a local antibiotic will be started one day prior to surgery.
INTRAOPERATIVE ASSESSMENT
Two point peribulbar anaesthesia was administered .4cc at the infero temporal quadrant and 3 cc at the supero nasal quadrant in all cases with the eye in primary position of gaze.
Grading of anaesthesia was done as follows:
1)grade 1 complete anaesthesia and akinesia demonstrated by
a)complete absence of eye movements
b)painless insertion of superior rectus bridal suture in any direction of gaze
c)complete anaesthesia of conjunctiva and cornea.
2)akinesia and anaesthesia adequate for safe intra ocular surgery
a)  eye movements <15 degree in any direction of gaze.
b)  painless insertion of superior rectus bridal suture.
c)  complete anaesthesia of conjunctiva and cornea.
3)grade 3 unsuccessful anaesthesia and akinesia
a)  eye movements >15 degree in any gaze.
b)  painful insertion of superior rectus bridal suture.
Patients with grade 3 anaesthesia will be given supplement injection of the same mixture at the end of 5 minutes.
Time taken for anaesthesia and akinesia will be recorded.
Duration of anaesthetic effect will be recorded
Immediate complications like sub conjunctival hemorrhage ,conjunctival chemosis and systemic side effects will be recorded.
POSTOPERATIVE ASSESSMENT:
Postoperatively, assessment will be done at the 1st, 7th, 21st and 42nd days. At each visit- Visual Acuity assessment, Anterior segment slit lamp examination, Fundoscopy will be done. Local and systemic complications of anaesthesia will be determined at each visit.
At the end of the 6th week best corrected visual acuity will be recorded.
INCLUSION CRITERIA:
Cataract patients, irrespective of grade of cataract-
(1) Between the ages of 40-60 years.
(2) Of either sex.
(3) With normal fundus.
(4) With normal intra-ocular pressure.
EXCLUSION CRITERIA:
1.  patients on pre operative sedatives,analgesics,anxiolytics .
2.  patients with profound cognitive impairment who were unable to understand the grading of pain or give informed consent .
3.  apprehensive patients who required sedatives and analgesics.
4.  patients with documented allergies to hyaluronidase and lignocaine .
5.  any preceeding eye disorder other than cataract.
STATISTICAL ANALYSIS:
Data will be analysed by
·  t-test and
·  Analysis Of Variance (ANOVA) for repeated measures.
·  -chi square test
7.3 DOES THE STUDY REQUIRE ANY INVESTIGATIONS OR INTERVENTIONS TO BE CONDUCTED ON PATIENTS OR OTHER HUMANS OR ANIMALS?
yes
7.4 HAS ETHICAL CLEARANCE BEEN OBTAINED FROM YOUR INSTITUTION IN CASE OF 7.3?
Yes
LIST OF REFERENCES
1.  William H H.Ocular Pharmacology.6th edition.St Louis.CV Mosby Company 1994;201-33
2.  Bloomerang B L.Bloomberg Anterior Periocular anesthesia technique.In:Gills P J,Hustead F R,Sanders R ,Ophthalmic anaesthesia,First edition.New delhi,Jaypee publications 1995;119-122.
3.  Davis B D,Mandel R M.Peribulbar anaesthesia,review of techniques and complications.Gills P J,Hustead F R,Sanders R D,ophthalmic anesthesia,First edition.New delhi.Jaypee publications1995;122-124
4.  Lewis P,Hamilton R C,Loken R G,Maltby J R,Strunin L,Comparison of plain with PH adjusted bupivacaine with hyaluronidase for peribulbar block.Canadian journal of anaesthesia1992;39(6):555-8.
5.  Roberts E. J,MacLeod A.B,Hollans H.,Improved peribulbar anaesthesia with alkalinization and hyaluronidase.Canadian journal of anaesthesia1993;40(9): 835-8.
6.  srinivasan M,Vamshidhar M,Gopal R,Banushre,sodium bicarbonate-An alternative to hyaluronidase in ocular anaesthesia for cataract surgery. Indian journal of ophthalmology 2000,48(4):285-9.
9. / SIGNATURE OF THE CANDIDATE
10. / REMARKS OF THE GUIDE
11. / NAME AND DESIGNATION OF
11.1 GUIDE
11.2 SIGNATURE
11.3 CO-GUIDE (IF ANY)
11.4 SIGNATURE
11.5 HEAD OF THE DEPARTMENT
11.6 SIGNATURE / DR. FRANCIS E.A. RODRIGUES
Professor & Head
Dept Of Ophthalmology
Father Muller Medical College.
DR. FRANCIS E.A. RODRIGUES
Professor& Head
Dept Of Ophthalmology.
Father Muller Medical College.
12. / 12.1 REMARKS OF THE CHAIRMAN AND PRINCIPAL
2.2 SIGNATURE