sleep apnoea surgery
In sleep surgery, success is defined as a fifty percent reduction in apnoea events and lowering the number below 20 events an hour.
Our prospective study has shown that we had a 80% success rate for some of the most challenging anatomy noted in published literature (Freedman III type anatomy-large tongues and small tonsils). None of the study patients here needed CPAP postoperatively. ESS (Sleepiness score) was reduced by 70%.
The overall success rate was lesser (60%). This was partly because some of the best outcomes (mostly from freedman II type Anatomy) failed to come for their post-operative sleep studies, as they felt much better and didn't feel the need to have another study. Another reason is that some who had worse sleep apnoea on their backs slept more on their side in the pre-operative study but more on their backs during post-operative study.
Traditionally difficult-Freedman III stage no longer is a barrier for sleep apnoea surgery. We are working on a new index to predict outcome better. The above data was presented at the Australian Conference (ASOHNS) in 2020. We hope to present the latest data and our work in the 2021 ASOHNS with further modifications to our technique. We believe we will continue to improve results with close observation, modifications and research.
PROSPECTIVE STUDY (25 patients)
Sleepiness (ESS) reduced by 70%
overall events reduced 60% (most difficult to treat had 80% success and all avoided CPAP as seen below).
Freedman 1 :100% success rate
Freedman 3 : (most difficult) 80% success rate: 8/10
Freedman 2 : In this group many changed their sleep position in the post-surgical study, which skewed the results. None in this group required post operative CPAP as seen below. Also, many others wished not to have post-surgery study as they felt much better.
Best compare the two orange columns and two yellow columns (Blue column was dependant on how much they slept on their backs on each study). Overall the patient's symptoms (snoring/ sleepiness) were significantly better after surgery and avoided CPAP. They needed a positional device.
PILOT STUDY (9 patients)
Pilot study allowed us to observe the success of this operation. * denotes patients sleeping more on their backs in the post-op study skewing the data. This was the case in the second patient who did not require post-op CPAP. The apparent increase was due to him sleeping almost always on the side in the pre-op study and, almost always on the back in the post-op study.
This patient's ESS (sleepiness score) reduced from 8 to 0. This patient was cured of the side sleep apnoea and could tolerate a side positioning device hence avoided CPAP.
We can now confidently say that all anatomical subtypes can benefit from sleep surgery, though everyone is offered or trialled non-surgical options.
Due to research and observation, we can better inform patients if they are likely to be cured or achieve over 50% reduction in apnoea events. We can identify those who have less favourable anatomy and still benefit by combining a positional device. Some may require surgery to improve their CPAP compliance. The only absolute contraindication for surgery is high anaesthetic or bleeding risk or scarring of the palate from prior surgery.