Application of desaturation index in post-surgery follow-up in children with obstructive sleep apnea syndrome

The Impact of Intermittent Hypoxemia on Left Atrial Remodeling in Patients with Obstructive Sleep Apnea Syndrome

Obstructive sleep apnea syndrome (OSAS) is a significant risk factor for left atrial (LA) remodeling. Intermittent hypoxemia occurs during the sleep cycle in patients with OSAS and plays a crucial role in cardiovascular pathologies such as stroke, arrhythmia, and coronary artery disease. However, there is very little information about the role of intermittent hypoxemia in LA remodeling in patients with OSAS. In total, 154 patients with sleep-related breathing disorders (SRBD) were prospectively recruited for this study. All enrolled SRBD patients underwent polysomnography and echocardiography. Significant OSAS was defined as an oxygen desaturation index (ODI) of ≥10 per hour. Intermittent hypoxia/reoxygenation (IHR) stimulation was used to test the effect of hypoxia on the viability, reactive oxygen species, apoptosis, and inflammation-associated cytokine expression in the HL-1 cell line. To investigate the effect of patients’ exosomes on HIF-1 and inflammation-associated cytokine expression, as well as the relationship between ODI and their expression, exosomes were purified from the plasma of 95 patients with SRBD and incubated in HL-1 cells. The LA size was larger in patients with significant OSAS than in those without. There was a significant association between ODI, lowest SpO2, mean SpO2, and LA size (all p < 0.05) but not between the apnea–hypopnea index and LA size. IHR condition caused increased LDH activity, reactive oxygen species (ROS) levels, and apoptosis in HL-1 cells and decreased cellular viability (all p < 0.05). The expression of HIF-1α, TNF-α, IL-6, and TGF-β increased in the IHR condition compared with the control (all p < 0.05). The expression of HIF-1α, IL-1β, and IL-6 increased in the HL-1 cells incubated with exosomes from those patients with significant OSAS than those without (all p < 0.05). There was a significantly positive correlation between ODI and the expression of HIF-1α, TNF-α, IL-1β, IL-6, and TGF-β; a significantly negative correlation between mean SpO2 and IL-6 and TGF-β; and a significantly negative correlation between the lowest SpO2 and HIF-1α (all p < 0.05). In conclusion, intermittent hypoxemia was strongly associated with LA remodeling, which might be through increased ROS levels, LDH activity, apoptosis, and the expression of HIF-1α and inflammation-associated cytokines.

Continuous oximetry recordings on the first post-operative night after pediatric adenotonsillectomy-a case-control study

BACKGROUND

Children with obstructive sleep apnea (OSA) with recurrent dips in oxygen saturation (SpO₂) during sleep are known to be at increased risk of post-operative airway compromise after adenotonsillectomy (AT). We aimed to determine the extent of desaturation on the first post-operative night in children known to have recurrent desaturation pre-operatively and to compare the extent of desaturation in that group with results in children known to have normal oximetry recordings pre-operatively.

METHODS

Prospective sequential recruitment of 57 children who had overnight oximetry performed on the first night after adenotonsillectomy was undertaken, including 28 with a McGill Oximetry Score (MOS) of 2-4 pre-operatively (high risk group) and 29 with a normal/inconclusive pre-operative MOS (low risk group). Oximetry parameters (mean SpO₂, SpO₂ nadir, and rates of SpO₂ dips below 90% and dips of ≥4%) were compared to the pre-operative oximetry result. Demographic and clinical factors, and the occurrence of post-operative complications, were derived from the medical record.

RESULTS

In the high risk group, the MOS improved in 23/28 children, but remained abnormal in 82%. Conversely, in the low risk group 26/29 (90%) had a normal post-operative oximetry. The remaining 3, all of whom had severe OSA on pre-operative polysomnography, had a lowered baseline SpO₂ post-operatively. Mean SpO₂ was slightly lower post-operatively in both groups. In the high risk group, all other SpO₂ measures improved post-operatively. Respiratory adverse events were more common in the high risk group as expected (39% compared to 3% in the low risk group, p = 0.001). An adverse event requiring clinical intervention was significantly more likely if the post-operative oximetry was abnormal (result unknown to the treating team), occurring in 73% of children with an abnormal compared with 32% of children with a normal post-operative oximetry (p = 0.002).

CONCLUSION

Most children with an abnormal oximetry pre-operatively continued to have an abnormal oximetry on the first night after AT, albeit somewhat improved. While adverse events were more frequent in children with an abnormal post-operative oximetry, half (54%) did not suffer a clinical respiratory adverse event despite having repetitive desaturations on downloadable oximetry. These findings support close clinical observation of children at high risk of complications post-operatively, especially those with abnormal oximetry pre-operatively, rather than focusing on recurrent dips in SpO₂ on post-operative oximetry downloads in the absence of clinically evident complications.

Impact of adenotonsillectomy in children with severe obstructive sleep apnea: A systematic review

OBJECTIVES

To determine the impact of adenotonsillectomy for treatment of severe obstructive sleep apnea (OSA) in children without comorbidities.

METHODS

A systematic review was performed to identify studies regarding adenotonsillectomy for treatment of children with severe sleep apnea. Polysomnographic parameters were considered as metric of cure and the number of patients of persistent apnea was calculated. Quality of evidence was graded using OCEBM (Oxford Center for Evidence Based Medicine) and MINORS (Methodological Index for Nonrandomized Studies) scores.

RESULTS

The systematic review included nine studies. Five studies were prospective and four retrospectives. No one was controlled. The number of subjects with severe OSA included was 499 with a prevalence of male. The mean age varied from 4.3 to 8.2. The follow-up period ranges from 1 to 23 months. The criteria for considering severe OSA ranges from AHI or RDI ≥10 to ≥30. All the trials have found a statistically significant reduction of postoperative AHI or RDI values in patients who had undergone adenotonsillectomy for severe OSA. The AHI and RDI improving varied from 57.7% to 93.3%. All the studies documented persistent OSA after adenotonsillectomy. The number of residual OSA considering AHI≥5 varied from 30 to 55.5%, in case of AHI ≥1 from 60 to 90.6%.

CONCLUSION

To the best of our knowledge, this is the first review regarding the effectiveness of adenotonsillectomy for severe OSA in otherwise healthy children. Adenotonsillectomy is partially effective in the treatment of severe OSA in children without comorbidities. However, it reduces the severity of OSA determining a significant reduction of polysomnographic parameters. These results suggest a clinical and polysomnographic follow-up after surgery in order to manage the residual mild and moderate OSA.

Louis EK, Penzel T, Dawson D, Westbrook PR. A comparison between auto-scored apnea-hypopnea index and oxygen desaturation index in the characterization of positional obstructive sleep apnea

OBJECTIVE

Evaluate the concordance between overall and positional oxygen desaturation indices (ODI) and apnea-hypopnea indices (AHI) according to two different definitions for positional obstructive sleep apnea (POSA).

METHODS

A total of 184 in-home polysomnograms were edited to simulate Level III home sleep apnea tests (HSAT) with the auto-scored AHI and ODI based on recording time. POSA was determined using 132 records with an AHI≥5 and at least 20 mins of recording time in both supine and non-supine positions. POSA was defined independently for the AHI and ODI based on ratios of overall/non-supine event/h ≥1.4 (O/NS) and supine/non-supine event/h≥2.0 (S/NS).

RESULTS

Correlation between the AHI and ODI was 0.97 overall, 0.94 for supine, and 0.96 for non-supine recording times (all p<0.001). For most records, differences between the AHI and ODI were small, with only 14% of the records having a AHI-ODI difference exceeding >5/hr, and 6% exceeding >10 events/hr. The positive and negative percent agreements were uniformly good to excellent across varying clinical POSA cutoffs; percent agreements (positive, negative) were: AHI≥5=0.99, 0.78; AHI≥10=0.96, 0.89; and AHI≥15=0.96, 0.89. Cohen's Kappa scores also showed substantial agreement for overall as well as supine and non-supine positions across varying clinical cutoffs of the AHI. Frequency of POSA was reproducibly uniform between 59% and 61% for both POSA criteria. When the O/NS and S/NS definitions conflicted in POSA characterization, O/NS was superior for identifying patients who might exhibit a greater response to supine restriction positional therapy.

CONCLUSIONS

Auto-scored positional oximetry is a clinically viable alternative to an auto-scored Level III HSAT AHI in the characterization of POSA based on a 3% desaturation.

The effects of tonsillectomy by low-temperature plasma on the growth development and psychological behavior in children with obstructive sleep apnea hypopnea syndrome

We investigated the effects of tonsillectomy by low-temperature plasma on the growth development and psychological behavior in children with obstructive sleep apnea hypopnea syndrome (OSAHS).This study included 72 moderate and severe OSAHS children with tonsils or adenoids hypertrophy, which were randomly assigned into either the study group (n = 36) or the control group (n = 36). Patients in study group underwent tonsillectomy by low-temperature plasma, while in the control group underwent tonsil-pecking, then the efficacy were compared.The time of surgery, VAS scores on postoperative day 1, 3, and 7 were significantly lower in the study group than in the control group, and the efficiency was significantly higher in the study group than the control group (P = .018). In the study group, the BMI was lower, the score of C-WISC (VIQ, PIQ, and FIQ) was higher, the score of CBCL social competence was higher and the score of behavioral questions was lower than that in the control group; differences were statistically significant (P = .022). The serum levels of IgA, IgG, and IgM, as well as the percentage of T lymphocytes, between the study group and the control group were not significantly different (P = .132).Tonsillectomy by low-temperature plasma was effective on the treatment of children with severe OSAHS, and could improve growth development and psychological behavior.

Value of pulse oximetry watch for diagnosing pediatric obstructive sleep apnea/hypopnea syndrome

OBJECTIVE

To evaluate the clinical value of pulse oximetry watch (POW) for diagnosing pediatric Obstructive sleep apnea/hypopnea syndrome (OSAHS).

METHODS

We selected 32 children (boys: 25, 4-16 years old) who came to the hospital for diagnosing OSAHS from July to October 2016. Polysomnography (PSG) and POW were used simultaneously and recorded the apnea hypopnea index (AHI), LSpO₂, and ODI₄. Pearson analysis, t test, and receiver-operating characteristic (ROC) were used to analyze the correlation between PSG-AHI and other indicators, the diagnosis accordance rate, and the sensitivity and specificity of POW, respectively.

RESULTS

According to PSG-AHI, 32 children were divided into two groups: primary snoring (n = 5) and OSAHS (n = 27). There was no significant difference between PSG-ODI₄ and POW-ODI₄ (p > .05). A statistically significant correlation between PSG-AHI and POW-ODI₄ was found (r = .719, p < .001). When PSG-AHI >1, 5, 10, 15, and 20 events/h, the area under the curve (AUC) was 0.685 (p > .05), 0.733, 0.798, 0.922, and 0.929 (p < .05), respectively. There were high levels of sensitivity (83.33%) and specificity (92.31%) in the OSAHS with AHI >20 events/h level, whereas the sensitivity and specificity were unacceptable (<75%) at the level of AHI >1, 5, 10, and 15 events/h.

CONCLUSIONS

POW cannot replace PSG to diagnose pediatric OSAHS because of low sensitivity and specificity, but can be used for screening severe OSAHS in children.