Evaluation of Rhythmic Masseter Muscle Activity during Sleep and Awake in Patients with Dentofacial Deformity.

Objectives: Investigate the activity of rhythmic masseter muscles activity (RMMA) during sleep in patients with dentofacial deformities. Materials and methods: Fifty patients with dentofacial deformities (16 male, 34 female) who required orthognathic surgery. An electrode was attached to the masseter muscle bilaterally, and preoperative polysomnography was performed. The frequency of RMMA onset per hour was measured on the left and the right sides. Values were classified as phasic (grinding: P-RMMA) and tonic (clenching: T-RMMA) to examine the onset of RMMA. Correlation between the RMMA index and various morphological and physical factors were determined including sleep or awake, rapid eye movement (REM), non-rapid eye movement (NREM) phases (NR1-NR4) in the sleep stage, phasic and tonic, gender, and mandibular asymmetry. Results: The RMMA index values at the time of sleep were significantly small than during awake. The values were significantly higher during the NREM sleep than during the REM sleep and were the highest in the NR1 phase. P-RMMA index was significantly higher than the T-RMMA index. The P-RMMA index was also significantly higher than the T-RMMA index for men. In patients with greater asymmetry in the RMMA index values between the left and the right side (more than 30% difference), deviation between the midpoint of the maxillary and the mandibular incisal edges (U1-L1 deviation) was significantly higher. Conclusion: RMMA in patients with dentofacial deformity was statistically higher in awake than sleep, higher in NREM sleep than REM sleep, higher in male than female on grinding, and higher in upper and lower incisor high deviation.

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.

[Usefulness of reticulocyte hemoglobin equivalent for the safety of pre-operative autologous blood donation].

Pre-operative autologous blood donation (PABD) provides safe blood for patients at the expense of the risk of iron deficiency anemia that may compromise the patients. The reticulocyte hemoglobin equivalent (RET-He) is an indirect measure of the functional iron available for the erythropoiesis over the previous 2-3 days. The aim of this study was to evaluate the clinical usefulness of RET-He quickly measured by the automated hematology analyzer Sysmex XE-2100 in patients undergoing PABD at our hospital. Receiver-operating characteristic curve analysis revealed that RET-He was reliable in the diagnosis of iron deficiency anemia. Two of 14 patients in the absence of post-PABD iron replacement developed marked anemia with low RET-He levels after PABD, suggesting that this anemia was due to iron deficiency. Of 26 patients receiving post-PABD iron replacement, 8 who had already showed low RET-He levels at PABD developed statistically significant reduction in hemoglobin levels after PABD despite adequate iron replacement, indicating that the 8 patients had iron deficiency prior to PABD. These findings suggest that automated measurement of RET-He may contribute to improve the safety of PABD.

Changes in molecular markers of hemostatic and fibrinolytic activation under various sampling conditions using vacuum tube samples from healthy volunteers.

Molecular makers such as thrombin-antithrombin complex (TAT), prothrombin fragment 1+2 (F1+2), soluble fibrin (SF), and D-dimer, are useful markers in the diagnosis and assessment of various thrombotic conditions. These markers are measured in plasma after blood sampling. Difficult blood sampling is known to falsely elevate plasma TAT levels. However, it is not known exactly why this occurs. In the present study, we examined how levels of molecular markers of haemostatic and fibrinolytic activation change under various sampling conditions using vacuum tube samples from healthy volunteers. When blood was sampled continuously by taking 10 consecutive vacuum tube samples following application of a tourniquet, blood sampling resulted in an accurate assessment of these molecular makers. When blood was sampled continuously by taking vacuum tube samples every one minute over a total of 9 minutes to investigate possible changes in the levels of the molecular markers over time, plasma levels of TAT, SF, and F1+2 gradually increased with time. Plasma levels of TAT, F1+2, and SF increased beyond the normal range over the course of nine minutes. When blood was sampled using three alternative methods, which varied in terms of the duration of needle puncture (sampling B), duration of tourniquet use (sampling C), or both (sampling A), plasma TAT and SF levels were significantly increased with all three methods, compared to control samples. Plasma F1+2 levels were significantly increased with sampling methods A and B, compared to control samples, but not with sampling method C. On the other hand, plasma D-dimer levels were not significantly altered by any of the sampling methods. In conclusion, the results suggest that molecular markers of haemostatic and fibrinolytic activation, except for D-dimer, may be affected by sampling method, particularly the duration of needle puncturing. Therefore, care needs to be taken when using TAT, F1+2, and SF levels to diagnose and estimate activation of the coagulation system.