2. Moffett’s solution causes significantly greater post-operative throat pain compared to Co-phenylcaine in sinonasal surgery
D. J. Ku
K. Vasan
E. Wong
E. Tseros
Prof. N. Singh
Department of Otolaryngology, Westmead Hospital
University of Sydney, New South Wales, Australia

3. Moffett and his solution
First described by Major Moffett of the Royal Army Medical Corps in paper “Postural Instillation”
Currently, the most common composition of Moffett’s solution is:
2ml of 10% cocaine (200mg), 1ml of 1:1000 adrenaline (1mg), 2mL of 1% sodium bicarbonate (20mg)

4. In Sinonasal surgery
Moffett’s solution is commonly used as a topical decongestant and local anaesthetic – better operative field
Cocaine, 2 pathways of action:
Vasoconstriction – presynaptic blockade of catecholamine reuptake, increasing stimulation Alpha-1 adrenergic receptors causing vasoconstriction
Analgesia – blocking sodium channels along the axons of sensory nerves

5. Safety of Moffett’s solution
Dosage for safe administration in the literature is
1.5mg/kg or MAX. 200mg
Topically applied – not to be injected
Rare adverse events – Feehan et al series of >100,000 patients Morbidity rate of 0.3% and Mortality of 0.005%
Cardiac events generally after submucosal infiltration

6. Throat pain Anecdotally, throat pain is very common post-operatively
Second most common side-effect, after tachycardia
We hypothesise that the pooling of the solution in the oropharynx cuases profound vasoconstriction in the mucosa, resulting in localised ischaemia and subsequent throat pain.

7. The Study 2 arms of 20 patients each: Patients were blinded
Intervention arm: Moffett’s solution topically applied via the MADgicTM atomiser
Control arm: Standard Co-phenylcaine ForteTM topical nasal spray
Patients were blinded
Primary outcome: Throat pain visual analogue scale (VAS)
Scores were recorded at 2 hours, 4 hours, 6 hours post-operatively and the next morning

8. Results
Figure 1: Post-operative visual analogue scores (0-10) for throat pain
Significantly higher score for throat pain at 2 and 4 hours post-op – pain 2x that of control
No systemic side effects either arm

9. Future directions
This study is the first to show a statistically significant increase in throat pain after the use of Moffett’s solution in sinonasal surgery
Future studies designed to investigate methods of preventing post- operative throat pain
Foley catheter occlusion of PNS
Suction of oropharynx after topical application