Obstructive Airway Compromise in the Early Postoperative Period After Orthognathic Surgery:

Risk Factors for Prolonged Mechanical Ventilation and Delayed Extubation Following Bimaxillary Orthognathic Surgery: A Single-Center Retrospective Cohort Study

Background: Bimaxillary orthognathic surgery bears the risk of severe postoperative airway complications. There are no clear recommendations for immediate postoperative follow-up and monitoring. Objective: to identify potential risk factors for prolonged mechanical ventilation and delayed extubation in patients undergoing bimaxillary orthognathic surgery. Methods: The data of all consecutive patients undergoing bimaxillary surgery between May 2012 and October 2019 were analyzed in a single-center retrospective cohort study. The clinical data were evaluated regarding baseline characteristics and potential factors linked with delayed extubation. Results: A total of 195 patients were included; 54.9% were female, and the median age was 23 years (IQR 5). The median body mass index was 23.1 (IQR 8). Nine patients (4.6%) were of American Society of Anesthesiologists Physical Status Classification System III or higher. The median duration of mechanical ventilation in the intensive care unit was 280 min (IQR, 526 min). Multivariable analysis revealed that premedication with benzodiazepines (odds ratio (OR) 2.60, 95% confidence interval (0.99; 6.81)), the male sex (OR 2.43, 95% confidence interval (1.10; 5.36)), and the duration of surgery (OR 1.54, 95% confidence interval (1.07; 2.23)) were associated with prolonged mechanical ventilation. By contrast, total intravenous anesthesia was associated with shorter ventilation time (OR 0.19, 95% confidence interval (0.09; 0.43)). Conclusion: premedication with benzodiazepines, the male sex, and the duration of surgery might be considered to be independent risk factors for delayed extubation in patients undergoing bimaxillary surgery.

Effect of Flumazenil on Emergence Agitation after Orthognathic Surgery: A Randomized Controlled Trial

Flumazenil, a gamma-aminobutyric acid receptor antagonist, can promote arousal even under general anesthesia without the use of benzodiazepines. We hypothesized that flumazenil could promote arousal and reduce emergence agitation in patients undergoing orthognathic surgery with sevoflurane anesthesia. One hundred and two patients were randomly allocated to the control or flumazenil group. Saline or flumazenil was administered at the end of the surgery. The incidence of emergence agitation was measured by using Aono’s four-point scale, with scores of 3 and 4 indicating emergence agitation. The primary outcome was the incidence of emergence agitation. Secondary outcomes included duration of emergence agitation and time intervals between the discontinuation of anesthetics, first response, extubation, and post-anesthesia care-unit discharge readiness. The incidence of emergence agitation was 58.3% and 38.9% in the control and flumazenil groups, respectively, but it was not statistically significant. However, the duration of emergence agitation was shorter in the flumazenil group (p = 0.012). There were no significant differences in the time intervals between the discontinuation of anesthetics, first response, and extubation. Although flumazenil did not reduce the incidence of emergence agitation in patients undergoing orthognathic surgery with sevoflurane anesthesia, it can be considered as an option for awakening patients in terms of improving emergence profiles.

Factors related to oxygen desaturation index during sleep 7 days after bilateral sagittal splitting ramus osteotomy in patients without previous obstructive sleep apnea

PURPOSE

The incidence of obstructive sleep apnea (OSA) immediately after surgery in patients with dentofacial deformities without previous OSA remains unknown. We aimed to perioperatively evaluate factors associated with oxygen desaturation index (ODI) during sleep, 7 days after bilateral splitting ramus osteotomy (BSSRO) in patients without previous OSA.

METHODS

Fifty-one patients (15 males, 36 females) with dentofacial deformities, scheduled to undergo BSSRO, were included. Polysomnography was performed before orthognathic surgery. Perioperative OSA was evaluated with peripheral arterial tonometry on the day of surgery and 1, 2, 3, 4, and 7 days postoperatively. Rapid eye movement (REM) sleep periods and the ODI were measured. Factors associated with perioperative ODI after surgery were statistically analyzed.

RESULTS

REM sleep periods were significantly decreased on the day of surgery and significantly increased at 4 and 7 days postoperatively, compared to the preoperative period. ODI increased on the day of surgery, decreased after 1 day, and increased again at 4 and 7 days postoperatively. ODI on the day of surgery was significantly increased due to increased preoperative ODI, overjet, and SN-MP angle and decreased SNA and SNB angle. ODI at 7 days postoperatively was significantly increased due to increased REM sleep periods and decreased SN-MP and gonial angle. ODI was increased in response to REM sleep periods 7 days after BSSO.

CONCLUSION

Airway management in patients with dentofacial deformity should be given more attention by preoperative assessment for OSA, even in the absence of previous OSA, until 7 days postoperatively due to REM rebound.

Intraoperative blood loss and surgical time according to the direction of maxillary movement

Background

Excessive bleeding is one of the most severe complications of orthognathic surgery (OGS). This study investigated the associations of intraoperative blood loss and surgical time with the direction of maxillary movement.

Methods

This retrospective study involved patients who underwent OGS from October 2017 to February 2020. They were classified based on whether maxillary setback was performed into groups A1 and B1, respectively. Relative blood loss (RBL, %) was used as an indicator to compare intraoperative blood loss between the two groups. The surgical time of the two groups was also measured. Subsequently, the patients were reclassified based on whether posterior impaction of the maxilla was performed into groups A2 and B2, respectively. RBL and surgical time were measured in the two groups. Simple linear and multiple regression analyses were performed. P-values <0.05 were considered to indicate statistical significance.

Results

Eighteen patients were included. The RBL and surgical time for the groups were: A1, 13.15%±5.99% and 194.37±42.04 minutes; B1, 12.41%±1.89% and 196.50±46.07 minutes; A2, 13.94%±3.82% and 201.00±39.70 minutes; and B2, 9.61%±3.27% and 188.84±38.63 minutes, respectively. Only RBL showed a statistically significant difference between the two groups (A2 and B2, P=0.04).

Conclusions

Unlike maxillary setback, posterior impaction of the maxilla showed a significant association with RBL during surgery. When performing posterior impaction of the maxilla, clinicians need to pay particular attention to surgery and postoperative care.

The effect of manual lymphatic drainage on patient recovery after orthognathic surgery-A qualitative and 3-dimensional facial analysis

OBJECTIVE

The aim of this study was to investigate the effect of manual lymphatic drainage (MLD) on postoperative facial swelling and pain.

STUDY DESIGN

A randomized, single-center, prospective, 2-arm clinical trial with blinded endpoint assessment was set up. Patients were enrolled from the Maxillofacial Department of the Ghent University Hospital (Belgium) between January 2015 and March 2018. Both the intervention group (n = 13) and the control group (n = 13) received the same postoperative care; in addition, the intervention group underwent 6 sessions of MLD after orthognathic surgery. Three-dimensional facial scans were performed and questionnaires administered on postoperative days 3, 7, 14, 30, 90, and 180. A linear mixed model was performed, and statistical significance was assumed at the 5% level.

RESULTS

In total, 26 patients (mean age 29 years; range 16-57 years) were included for statistical analysis. A faster decrease in swelling in the intervention group was observed on 3-dimensional scans. Furthermore, patients receiving MLD reported reduction in swelling and pain within the first month after surgery. However, no statistically significant difference could be detected in these observations (P > .05).

CONCLUSIONS

Within the limitations of this study, no statistically significant difference could be found between patients treated with or without MLD after orthognathic surgery with regard to swelling and pain.

Posterior Pharyngeal Airway in Clockwise Rotation of Maxillomandibular Complex Using Surgery-first Orthognathic Approach

Background:

Because obstructive sleep apnea is known to be an important preexisting factor causing chronic disease, many investigations have been done recently. There have been few reports regarding the posterior pharyngeal airway after clockwise rotation of maxillomandibular complex. Because the 2-jaw surgery in class III patients could cause obstructive sleep apnea or snoring, we investigated the posterior pharyngeal airway change of the clockwise maxillomandibular complex in the surgery-first orthognathic approach for the correction of class III dentofacial deformities.

Methods:

A cephalometric evaluation of 35 patients with skeletal class III deformity was performed preoperatively and postoperatively. Three measurements of the posterior pharyngeal airway space (nasopharynx, oropharynx, and hypopharynx) and hyoid bone positions (the distance from palatal plane to hyoid bone and the distance from mandibular plane to the hyoid bone) were evaluated and correlated with the skeletal movement of the jaws using imaging software (V-Ceph, Osstem, Seoul, Korea).

Results:

The preoperative airway space turned out to be enlarged in class III dentofacial deformities compared with those of normal persons. The preoperative P1, P2, and P3 in our cohort were increased and posterior nasal spine to hyoid bone and mandibular plane to hyoid bone were decreased compared with those of normal person’s data because the cohort consists of prognathic patients where the mandible is located in forward position. After 6 months, most values were nearly normal.

Conclusion:

Orthognathic surgery based on clockwise rotation of maxillomandibular complex did not cause severe posterior airway space changes at 6 months postoperation.

Emergence agitation after orthognathic surgery: a randomised controlled comparison between sevoflurane and desflurane

BACKGROUND

This study aimed to compare emergence agitation following sevoflurane and desflurane anaesthesia in adults undergoing orthognathic surgery. The hypothesis was that there might be a difference in the incidence of emergence agitation following sevoflurane and desflurane anaesthesia considering the difference in blood solubility and speed of recovery between the two.

METHODS

In this prospective randomised double-blind study, 144 adults undergoing orthognathic surgery were randomly allocated to either sevoflurane or desflurane anaesthesia. The incidence of emergence agitation and possible causative factors were then compared between the groups.

RESULTS

The incidence of emergence agitation was lower in the desflurane group than in the sevoflurane group (24% vs. 71%, P < 0.001). In addition, the time intervals between the discontinuation of anaesthetics and the first response, extubation, and discharge from post-anaesthesia care unit were significantly shorter in the desflurane group (P = 0.002, P < 0.001 and P = 0.003, respectively). The other variables were similar in the two groups.

CONCLUSIONS

In adults undergoing orthognathic surgery, desflurane anaesthesia was associated with less emergence agitation than was sevoflurane anaesthesia.

Three-dimensional computed tomographic evaluation of bilateral sagittal split osteotomy lingual fracture line and le fort I pterygomaxillary separation in orthognathic surgery using cadaver heads: ultrasonic osteotome versus conventional saw

PURPOSE

The purpose of this study was to observe the quality of the fracture line on the lingual side of the mandible after sagittal split osteotomy and the quality of pterygomaxillary separation after Le Fort I osteotomy using the BoneScalpel ultrasonic osteotome.

MATERIALS AND METHODS

Bimaxillary procedures, according to the standard protocol, were performed using 10 fresh cadaver heads. The ultrasonic osteotome was used in the study group, and a reciprocating saw was used in the control group. Three-dimensional reconstructions of postoperative computed tomographic scans were obtained. The lingual ramus fracture pattern and the pterygomaxillary separation pattern were observed, classified, and compared. Postoperative dissections of the skulls were performed to assess the integrity of the infra-alveolar nerve and the descending palatine artery.

RESULTS

No significant differences were found in the cutting time of bone between the BoneScalpel and the sagittal saw. Of the sagittal split osteotomies in the study group, 90% showed a good pattern (vertical pattern of fracture line extending to the inferior border of the mandible running behind the mandibular canal) compared with 50% of the sagittal split osteotomies in the control group. Ideal separation of the pterygoid plates without fractures was observed in 80% of the Le Fort I osteotomies in the study group compared with 50% of the osteotomies in the control group. High-level fractures occurred in 30% of cases in the control group compared with none in the study group. The integrities of the infra-alveolar nerve and the descending palatine artery were preserved in all cases.

CONCLUSION

Use of the ultrasonic BoneScalpel did not require more time than the conventional method. An improved pattern of lingual fracture lines in mandibular sagittal split osteotomy procedures and the pattern of pterygomaxillary separation in Le Fort I osteotomy procedures were observed.

Comparative analysis of the amount of postoperative drainage after intraoral vertical ramus osteotomy and sagittal split ramus osteotomy

Objectives

The purpose of this retrospective study was to compare the amount of postoperative drainage via closed suction drainage system after intraoral vertical ramus osteotomy (IVRO) and sagittal split ramus osteotomy (SSRO).

Materials and Methods

We planned a retrospective cohort study of 40 patients selected from a larger group who underwent orthognathic surgery from 2007 to 2013. Mean age (range) was 23.95 (16 to 35) years. Patients who underwent bilateral IVRO or SSRO were categorized into group I or group II, respectively, and each group consisted of 20 patients. Closed suction drainage system was inserted in mandibular osteotomy sites to decrease swelling and dead space, and records of drainage amount were collected. The data were compared and analyzed with independent t-test.

Results

The closed suction drainage system was removed at 32 hours postoperatively, and the amount of drainage was recorded every 8 hours. In group I, the mean amount of drainage was 79.42 mL in total, with 31.20 mL, 19.90 mL, 13.90 mL, 9.47 mL, and 4.95 mL measured at 0, 8, 16, 24, and 32 hours postoperatively, respectively. In group II, the mean total amount of drainage was 90.11 mL, with 30.25 mL, 25.75 mL, 19.70 mL, 8.50 mL, and 5.91 mL measured at 0, 8, 16, 24, and 32 hours postoperatively, respectively. Total amount of drainage from group I was less than group II, but there was no statistically significant difference between the two groups (P=0.338). There was a significant difference in drainage between group I and group II only at 16 hours postoperatively (P=0.029).

Conclusion

IVRO and SSRO have different osteotomy design and different extent of medullary exposure; however, our results reveal that there is no remarkable difference in postoperative drainage of blood and exudate.