Clinical manifestations of obstructive sleep apnoea in pregnancy: more than snoring and witnessed apnoeas

Society of Anesthesia and Sleep Medicine and the Society for Obstetric Anesthesia and Perinatology Consensus Guideline on the Screening, Diagnosis, and Treatment of Obstructive Sleep Apnea in Pregnancy

The Society of Anesthesia and Sleep Medicine and the Society for Obstetric Anesthesia and Perinatology tasked an expert group to review existing evidence and to generate recommendations on the screening, diagnosis, and treatment of patients with obstructive sleep apnea during pregnancy. These recommendations are based on a systematic review of the available scientific evidence and expert opinion when scientific evidence is lacking. This guideline may not be appropriate for all clinical situations and patients, and physicians must decide whether these recommendations are appropriate for their patients on an individual basis. We recognize that not all pregnant people may identify as women. However, data on non-cisgendered pregnant patients are lacking, and many published studies use gender-binary terms; therefore, depending on the study referenced, we may refer to pregnant individuals as women. This guideline may inform the creation of clinical protocols by individual institutions that consider the unique considerations of their patient populations and the available resources.

Asthma in pregnancy

Background: Asthma is a frequent and potentially life-threatening disease that complicates many pregnancies. There are extensive data with regard to the diagnosis and treatment of asthma during pregnancy. Medical providers require an up-to-date summary of the critical aspects of asthma management during pregnancy. Objective: This review aimed to summarize the available data from clinical trials, cohort studies, expert opinions, and guideline recommendations with regard to asthma in pregnancy. Methods: A search through PubMed was conducted by using keywords previously mentioned and MeSH (Medical Subject Headings) terminology. Clinical trials, observational studies, expert opinions, guidelines, and other reviews were included. The quality of the studies was assessed, and data were extracted and summarized. Results: Asthma worsens in ∼40% of pregnant women, which can be associated with maternal and fetal complications. Physiologic changes in the respiratory, cardiovascular, and immune systems during pregnancy play a critical role in the manifestations of asthma. The diagnosis and the treatment of asthma are similar to that of patients who are not pregnant. Nonetheless, concern for fetal malformations, preterm birth, and low birth weight must be considered when managing pregnant patients with asthma. Importantly, cornerstones of the pharmacotherapy of asthma seem to be safe during pregnancy. Conclusion: Asthma in pregnancy is associated with adverse outcomes. Roadblocks to management include associated comorbidities, medication nonadherence, atopy, lack of education, and smoking habits. These need to be acknowledged and addressed for successful asthma management during pregnancy.

Feto-placental Dopplers are not altered in women with obstructive sleep apnoea symptoms

BACKGROUND

Snoring, gasping or choking during sleep are common symptoms of sleep-disordered breathing and are associated with multiple adverse maternal and obstetric outcomes. The mechanisms responsible remain unknown; however, placental dysfunction is suspected.

AIMS

The aim of this study was to investigate feto-placental and fetal cardiac function in women with pregnancies complicated by obstructive sleep apnoea symptoms.

MATERIALS AND METHODS

This was a prospective observational cohort study at a large tertiary obstetric hospital in Australia. Women were asked to complete a questionnaire relating to the presence and severity of obstructive sleep apnoea symptoms. They also underwent an ultrasound scan where Doppler indices of various feto-placental vessels and fetal cardiac function were measured. Regional cerebral perfusion was also assessed.

RESULTS

A total of 255 women were included in the final analysis. Of these, 36.1% (92/255) of women reported no obstructive sleep apnoea symptoms; 63.9% (163/255) reported they experienced some form of obstructive sleep apnoea symptoms that included any frequency of snoring or choking/gasping, while 42.0% (107/255) complained of severe obstructive sleep apnoea symptoms (snoring ≥ 3 times a week or choking/gasping). There were no significant differences in feto-placental Dopplers or fetal cardiac function parameters in women with obstructive sleep apnoea symptoms. There were also no differences in regional cerebral blood flow between groups, or any correlation with severity of symptoms.

CONCLUSIONS

Our data challenge the current perspective that adverse perinatal outcomes in women with obstructive sleep apnoea symptoms are related primarily to placental dysfunction and fetal compromise.

Sleep and sleep disorders in pregnancy

Pregnancy is associated with a number of physiologic changes in the body including hormonal, anatomical, and mechanical. These changes alter many physiologic functions including sleep. The literature suggests that a number of women develop changes in duration, pattern, and quality of sleep during pregnancy. In addition, these changes also pave the way for expression of sleep disorders (e.g., insomnia, obstructive sleep apnea, and restless legs syndrome). Change in sleep and appearance of sleep disorders not only influence pregnant women, but also have negative influences on the fetus and outcomes of pregnancy. However, optimal management of these disorders may reverse adverse consequences. In this chapter, risk factors, clinical presentation, and management of insomnia, obstructive sleep apnea, and restless legs syndrome during pregnancy are discussed in view of the available literature.

Prospective Observational Investigation of Capnography and Pulse Oximetry Monitoring After Cesarean Delivery With Intrathecal Morphine

BACKGROUND

Intrathecal morphine provides excellent analgesia after cesarean delivery; however, respiratory events such as apnea, bradypnea, and hypoxemia have been reported. The primary study aim was to estimate the number of apneas per subject, termed "apnea alert events" (AAEs) defined by no breath for 30-120 seconds, using continuous capnography in women who underwent cesarean delivery.

METHODS

We performed a prospective, observational study with institutional review board approval of women who underwent cesarean delivery with spinal anesthesia containing 150-µg intrathecal morphine. A STOP-Bang obstructive sleep apnea assessment was administered to all women. Women were requested to use continuous capnography and pulse oximetry for 24 hours after cesarean delivery. Nasal sampling cannula measured end-tidal carbon dioxide (EtCO2) and respiratory rate (RR), and oxygen saturation (SpO2) as measured by pulse oximetry. Capnography data were defined as "valid" when EtCO2 >10 mm Hg, RR >5 breaths per minute (bpm), SpO2 >70%, or during apnea (AAE) defined as "no breath" (EtCO2, <5 mm Hg) for 30-120 seconds. Individual respiratory variable alerts were 10-second means of EtCO2 <10 mm Hg, RR <8 bpm, and SpO2 <94%. Nurse observations of RR (hourly and blinded to capnography) are reported.

RESULTS

We recruited 80 women, mean (standard deviation [SD]) 35 (5) years, 47% body mass index >30 kg/m2/weight >90 kg, and 11% with suspected obstructive sleep apnea (known or STOP-Bang score >3). The duration of normal capnography and pulse oximetry data was mean (SD) (range) 8:28 (7:51) (0:00-22:32) and 15:08 (6:42) (1:31-23:07) hours:minutes, respectively; 6 women did not use the capnography. There were 198 AAEs, mean (SD) duration 57 (27) seconds experienced by 39/74 (53%) women, median (95% confidence interval for median) (range) 1 (0-1) (0-29) per subject. Observation of RR by nurses was ≥14 bpm at all time-points for all women, r = 0.05 between capnography and nurse RR (95% confidence interval, -0.04 to 0.14). There were no clinically relevant adverse events for any woman. Sixty-five women (82%) had complaints with the capnography device, including itchy nose, nausea, interference with nursing baby, and overall inconvenience.

CONCLUSIONS

We report 198 AAEs detected by capnography among women who underwent cesarean delivery after receiving intrathecal morphine. These apneas were not confirmed by the intermittent hourly nursing observations. Absence of observer verification precludes distinction between real, albeit nonclinically significant alerts with capnography versus false apneas. Discomfort with the nasal sampling cannula and frequent alerts may impact capnography application after cesarean delivery. No clinically relevant adverse events occurred.

The role of sleep duration and sleep disordered breathing in gestational diabetes mellitus

Many women experience sleep problems during pregnancy. This includes difficulty initiating and maintaining sleep due to physiologic changes that occur as pregnancy progresses, as well as increased symptoms of sleep-disordered breathing (SDB). Growing evidence indicates that sleep deficiency alters glucose metabolism and increases risk of diabetes. Poor sleep may exacerbate the progressive increase in insulin resistance that normally occurs during pregnancy, thus contributing to the development of maternal hyperglycemia. Here, we critically review evidence that exposure to short sleep duration or SDB during pregnancy is associated with gestational diabetes mellitus (GDM). Several studies have found that the frequency of GDM is higher in women exposed to short sleep compared with longer sleep durations. Despite mixed evidence regarding whether symptoms of SDB (e.g., frequent snoring) are associated with GDM after adjusting for BMI or obesity, it has been shown that clinically-diagnosed SDB is prospectively associated with GDM. There are multiple mechanisms that may link sleep deprivation and SDB with insulin resistance, including increased levels of oxidative stress, inflammation, sympathetic activity, and cortisol. Despite emerging evidence that sleep deficiency and SDB are associated with increased risk of GDM, it has yet to be demonstrated that improving sleep in pregnant women (e.g., by extending sleep duration or treating SDB) protects against the development of hyperglycemia. If a causal relationship can be established, behavioral therapies for improving sleep can potentially be used to reduce the risk and burden of GDM.

Síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) y embarazo

El embarazo es una condición temporal de la vida en la que ocurren importantes cambios en la fisiología de la mujer, los cuales se resuelven, en gran medida, después del parto. Hay cambios físicos, hormonales y psicológicos, con un aumento progresivo de peso. Estos factores pueden predisponer a un trastorno respiratorio del sueño o a exacerbar alguno ya existente. La literatura científica sugiere una mayor prevalencia de ronquido en las mujeres embarazadas. Las bases de datos demuestran que en menos del 1% de los embarazos aparece el código del diagnóstico de apnea de sueño. Se ha relacionado la presencia tanto de ronquido como de apnea durante el embarazo con algunos desenlaces adversos que se tratan en este artículo, el cual busca sensibilizar a los médicos para que consideren este diagnóstico durante el embarazo.

Sleep Disordered Breathing in Pregnancy and Adverse Maternal Outcomes-A True Story?

Pregnancy may predispose women to the development or worsening of sleep disordered breathing. Recent studies have shown a significant association between sleep disordered breathing and adverse pregnancy-related outcomes including gestational diabetes, preeclampsia, and severe maternal morbidity including pulmonary edema, cardiomyopathy, congestive heart failure, and admissions to the intensive care unit. More research is needed on the mechanisms linking sleep disordered breathing to adverse pregnancy outcomes. Large trials that examine the impact of therapy for sleep disordered breathing during pregnancy on pregnancy outcomes are also needed.

Sleep disordered breathing in pregnancy: the maternal and fetal implications

Sleep disordered breathing (SDB) which includes obstructive sleep apnoea (OSA) and upper airway resistance syndrome (UARS), has emerged as a risk factor for adverse maternal-foetal outcomes in pregnancy. Physiological changes of pregnancy predispose a woman 'at risk' towards developing SDB. The increasing incidence of OSA in pregnancy closely correlates with the population trends of obesity. Common screening tools validated in non-pregnant subjects including Epworth Sleepiness Scale (ESS) and Berlin Questionnaire (BQ) are poor predictors of SDB in pregnancy. Preeclampsia, gestational hypertension and gestational diabetes mellitus (GDM) are linked with SDB. Preeclampsia and OSA share common pathological associations. It is unclear if one predisposes the other. Foetal morbidity includes intrauterine growth restriction (IUGR), preterm delivery, low birth weight, neonatal intensive care unit (NICU) admission and Apgar score of less than seven at one minute. Continuous positive airway pressure (CPAP) is a well-documented treatment of SDB in pregnancy and has been shown to reverse some of the adverse events. It becomes imperative to diagnose and manage this condition as OSA causes substantial morbidity in the untreated pregnant patient and foetus. Three short clinical cases and a literature review on SDB on pregnancy are presented.

Sleep Disordered Breathing and Adverse Pregnancy Outcomes

Sleep disordered breathing (SDB) occurs in 0.6% to 15% of reproductive-aged women. Because of an overlap in symptoms of SDB and normal pregnancy findings, the diagnosis of SDB in pregnancy is challenging. The repetitive arousals, sleep fragmentation, and hypoxias experienced by patients with SDB lead to an increase in oxidative stress and inflammation. In the nonpregnant population SDB is associated with an increased risk of diabetes mellitus, heart disease, and stroke. Increasing evidence identifies an association between SDB in pregnancy and gestational diabetes, preeclampsia, and fetal growth abnormalities.

Sleep disorders in pregnancy

Sleep disturbances are common in pregnancy and may be influenced by a multitude of factors. Pregnancy physiology may predispose to sleep disruption but may also result in worsening of some underlying sleep disorders, and the de novo development of others. Apart from sleep disordered breathing, the impact of sleep disorders on pregnancy, fetal, and neonatal outcomes is poorly understood. In this article, we review the literature and discuss available data pertaining to the most common sleep disorders in perinatal women. These include restless legs syndrome, insomnia, circadian pattern disturbances, narcolepsy, and sleep-disordered breathing.

Fetal breathing movements and changes at birth

The fetus, which develops within a fluid-filled amniotic sac, relies on the placenta for respiratory gas exchange rather than the lungs. While not involved in fetal oxygenation, fetal breathing movements (FBM) nevertheless have an important role in lung growth and in development of respiratory muscles and neural regulation. FBM are regulated differently in many respects than postnatal respiration, which results from the unique intrauterine environment. Prominent distinctions of FBM include its episodic nature and apnea-sensitivity to hypoxia. The latter characteristic is the basis for using FBM in the assessment of fetuses at risk for hypoxic injury. At birth, the transition to continuous postnatal respiration involves a fall in temperature, gaseous distention of the lungs, activation of the Hering-Breuer reflexes, and functional connectivity of afferent O2 chemoreceptor activity with respiratory motoneurons and arousal centers. Importantly, exposure to drugs or adverse conditions in utero not only can change patterns of FBM but also can lead to epigenetic dysregulation in postnatal respiration. Such changes, can blunt respiratory and arousal defenses against hypoxic challenges in sleep. Thus, fetal hypoxia and/or drug exposure may in later life dispose sleeping infants, children, and adults to hypertension, diabetes mellitus, brain injury, and sudden death.