Does a patient's Mallampati score predict outcome after maxillomandibular advancement for obstructive sleep apnoea?

The Mallampati airway classification has been used to estimate the success of uvulopalatopharyngoplasty in patients with obstructive sleep apnoea (OSA) but its predictive value in maxillomandibular advancement has not been proved. We aimed to explore the association between preoperative Mallampati scores and surgical outcome after bimaxillary advancement for OSA. We retrospectively analysed data on 50 patients who had maxillofacial operations for OSA at our hospital and stratified them into two groups based on Mallampati scores: high (class III/IV) and low (class I/II). We compared pre- and postoperative apnoea/hypopnoea indices (AHIs), Epworth sleepiness scores, and lowest recorded oxygen saturation in both groups. The postoperative values for all three outcome measures were not significantly different when patients were stratified according to the Mallampati classification (mean (SD) AHI was 41(19) before and 7 (6) after operation in the low group, and 42 (15) before and 9 (7) after in the high group). Success rates (AHI less than 15 postoperatively) were similar in both low and high score groups (p>0.05). Maxillomandibular advancement alleviates obstruction at multiple levels and our study has shown comparable surgical outcomes in both groups. The Mallampati score can be used to optimise patient selection for surgeons considering single-level procedures for OSA. Our study suggests that the Mallampati classification is less useful for the prediction of surgical outcome after maxillomandibular advancement surgery.

Effects of maxillomandibular advancement on systemic blood pressure in patients with obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is associated with resistant hypertension. We investigated to what extent maxillomandibular advancement affected a patient's blood pressure postoperatively. We retrospectively analysed consecutive patients who had Bimaxillary advancement for OSA at our hospital following referral from the local sleep clinic. We collected relevant data on clinical characteristics and explored the changes in systolic and diastolic blood pressures, as well as mean arterial pressure (MAP) preoperatively, with those taken 6 months following surgery. We identified 51 patients with a mean (SD) age of 44 (8) years and a mean (SD) body mass index of 29 (3.4). Preoperative and postoperative data on blood pressure were available for analysis in 45. The mean (SD) systolic blood pressure was significantly reduced in our sample following surgery (from 131(12.6) to 127 (12.5)mmHg, p<0.001). The mean (SD) reduction in postoperative MAP values in the overall group, approached statistical significance (recorded MAP 96.6(10) to 93.1(8)mmHg, p=0.06). In a subgroup of 10 patients who had established hypertension the reduction in values postoperatively (mean reduction: systolic blood pressure 6 mmHg, diastolic blood pressure 10 mmHg, mean arterial pressure 9 mmHg) was greater than that observed in the overall group. Our results have shown an improvement in systemic blood pressure after maxillomandibular advancement for OSA, particularly in those with established hypertension. The data suggest that in addition to being a highly effective treatment for OSA, this surgery may more effectively lower systemic blood pressure than other treatment modalities.

Innovative use of anterior subapical setback combined with bilateral sagittal split osteotomy in patients with obstructive sleep apnoea.

We describe the use of anterior mandibular subapical setback osteotomy combined with bilateral sagittal split osteotomy in the treatment of selected patients with obstructive sleep apnoea (OSA). The technique enables maximal mandibular advancement, it alleviates pharyngeal narrowing, and minimises the alteration to the mid facial profile that is associated with traditional maxillomandibular advancement.

How often does the operating list follow the planned order? An analysis of elective maxillofacial operating lists.

OBJECTIVES: The authors explored consistency of the observed running order in operating sequence compared with prior scheduled listing. We analysed potential variables felt to be predictive in the chances of a patient having their procedure as previously scheduled. METHODS: Data were retrospectively collected for a consecutive group of patients who underwent elective maxillofacial procedures over a four week period. The consistency of scheduled and observed running order was documented. We considered four independent variables (original list position, day of week, morning or afternoon list, seniority of surgeon) and analysed their relationship to the probability of a patient undergoing their operation as per listing. Logistic regression analysis was used to determine significant associations between predictor variables with an altered list order. RESULTS: Data were available for 35 lists (n = 133). 49% of lists were found to run according to prior given order, the remainder subject to some alteration. Logistic regression analysis showed a statistically significant association between original scheduled position and day of week, with list position consistency. Patients listed first were twelve times more likely to have their operation as listed compared to those placed fourth (OR 12.7, 95% CI 3.7-43, p < 0.05). Operating lists at the start of a week were subject to less alteration (p < 0.05). There was no demonstrated relationship between the grade of surgeon operating and alteration in operating sequence. CONCLUSION: Approximately half of lists showed some alteration to the previously printed order. It appears that being first on an elective list offers the greatest guarantee that a patient will have their operation as per prior schedule. It may be reasonable for clinicians to be mindful of potential operating list alterations when preparing their patients for elective surgery.

Effect of preoperative continuous positive airway pressure duration on outcomes after maxillofacial surgery for obstructive sleep apnoea.

Continuous positive airway pressure (CPAP) remains the first-line treatment for obstructive sleep apnoea (OSA), and is known to result in various physiological changes. The objective of this study was to evaluate the association between duration of preoperative CPAP therapy and outcome after maxillomandibular advancement (MMA) for OSA. We retrospectively analysed consecutive patients treated at our institution, and divided them into 2 groups based on duration of treatment with CPAP: short-term (up to 12 months) and long-term use (12 months or more). We controlled for baseline demographic and clinical characteristics. We compared postoperative scores for the apnoea/hypopnoea index (AHI) and the Epworth sleepiness scale (ESS), and lowest recorded oxygen saturation between groups. In 43 patients data were available on the preoperative use of CPAP, and in 37 of them preoperative and postoperative polysomnographic data were also available for inclusion. Most had bimaxillary advancement with genioplasty. Differences between the groups in mean reduction in the AHI and lowest oxygen saturation were not significant, and operative success rates were comparable. After operation, the reduction in ESS scores was significantly greater in the long-term group than in the short-term group (mean (SD) 8(3) compared with 2 (2), respectively, p<0.001). Our results suggest that the duration of use of CPAP preoperatively does not significantly influence objective outcome measures. The reduction in AHI scores after MMA was equivalent in both groups. The long-term group seemed to fare better than the short-term group on subjective outcome measures.

Subjective assessment of facial aesthetics after maxillofacial orthognathic surgery for obstructive sleep apnoea.

We aimed to evaluate the subjective perception of facial appearance by patients after maxillofacial surgery for obstructive sleep apnoea (OSA), and explored the possible correlation between satisfaction and surgical outcome. A total of 26 patients, 24 men and 2 women (mean (SD) age 45 (7) years), subjectively assessed their facial appearance before and after operation using a visual analogue scale (VAS). To investigate a possible association between postoperative facial appearance and surgical outcome, we analysed postoperative scores for the apnoea/hypopnoea index (AHI) and Epworth sleepiness scale (ESS). Postoperatively, 14 (54%) indicated that their facial appearance had improved, 4 (15%) recorded a neutral score, and 8 (31%) a lower score. The rating of facial appearance did not correlate with changes in the AHI or ESS following surgery. This study supports the view that most patients are satisfied with their appearance after maxillofacial orthognathic surgery for OSA. The subjective perception of facial aesthetics was independent of the surgical outcome.

Does the Kushida morphometric model predict outcomes following maxillomandibular advancement surgery for obstructive sleep apnoea?

OBJECTIVE: The primary aim of this study was to explore the predictive potential of the preoperative Kushida index score and subsequent outcome following maxillomandibular advancement surgery (MMA). Secondarily we looked at how well the Kushida values of our OSA patients matched the morphometric models diagnostic thresholds. METHODS: We performed a retrospective analysis of patients who underwent MMA for OSA at our institution. Kushida morphometric scores were calculated using the described formula: P + (Mx - Mn) + 3 × OJ + 3 × [Max (BMI - 25)] × (NC ÷ BMI). Regression analysis was performed to explore the possible association between Kushida index score and outcome variables of postoperative apnoea/hypopnea indices (AHI) and Epworth Sleepiness Scores (ESS). RESULTS: We identified 28 patients with complete data available for analysis. The mean age was 45 years (SD 6) with mean BMI of 28 (SD 3). All, but one patient underwent bi-maxillary procedure with or without genioplasty, with a mean advancement of 8.5 mm (SD 2). The mean Kushida index score in our sample was 79 (SD 14). 89% of patients had postoperative AHI <15 in keeping with surgical success. We found no statistically significant relationship with Kushida morphometric model variables and overall score with either of our outcome variables. CONCLUSION: The mean Kushida index score in our patients was in the range consistent with the morphometric models diagnostic cut-off for OSA. Kushida's morphometric model does not appear to be a good predictor of postoperative success in individuals following MMA. The morphometric model represents a clinical adjunct in the initial diagnostic work-up of OSA patients referred for surgery.

Orthognathic surgery in the management of obstructive sleep apnoea: experience from maxillofacial surgery unit in the United Kingdom.

In the United Kingdom, maxillofacial techniques are underused in the treatment of obstructive sleep apnoea (OSA). We retrospectively analysed the details and relevant clinical data of consecutive patients who had operations for OSA at the maxillofacial unit in Leicester between 2002 and 2012. They had been referred from the local sleep clinic after investigation and diagnosis, and in all cases treatment with continuous positive airway pressure (CPAP) had failed. We compared preoperative and postoperative apnoea/hypopnoea indices (AHI), scores for the Epworth sleepiness scale (ESS), and lowest oxygen saturation to measure surgical success (AHI of less than 15 and a 50% reduction in the number of apnoeas or hypopnoea/hour) and surgical cure (AHI of less than 5). We identified 51 patients (mean age 44 years, range 21-60) with a mean (SD) body mass index (BMI) of 29 (3.4). Most patients had bimaxillary advancement with genioplasty (n=42). Differences in mean (SD) preoperative and postoperative values were significant for all 3 outcome measures (AHI: 42 (17) to 8 (7) p<0.001; ESS: 14 (4) to 5 (4) p<0.001; lowest oxygen saturation: 76% (11%) to 83% (7%); p=0.006). On the postoperative sleep study 85% of patients met the criteria for surgical success. Our experience has confirmed that bimaxillary advancement results in a high rate of success in patients with OSA. The operation has a role in the management of selected patients in the UK who do not adhere to CPAP.