Gastric Point of Care Ultrasound in Adults: Image Acquisition and Interpretation.

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical inquiries related to gastric content. One emerging concern pertains to patients about to undergo sedation and/or endotracheal intubation: the elevated risk of aspiration from the patient's stomach contents. Aspiration of gastric contents into the lungs poses a serious and potentially life-threatening complication. This occurs more frequently when the stomach is considered "full" and can be affected by the techniques employed for airway management, making it potentially preventable. To mitigate the risk of peri-procedural aspiration, two distinct medical specialties (anesthesiology and critical care medicine) have independently developed techniques to utilize ultrasonography for identifying patients requiring "full stomach" precautions. Due to these separate specialties, the work of each group remains relatively unfamiliar outside its respective field. This article presents descriptions of both techniques for gastric ultrasound. Furthermore, it explains how these approaches can complement each other when one of them falls short. Regarding image acquisition, the article covers the following topics: indications and contraindications, selection of the appropriate probe, patient positioning, and troubleshooting. The article also delves into image interpretation, complete with example images. Additionally, it demonstrates how one of the two techniques can be employed to estimate gastric fluid volume. Lastly, the article briefly discusses medical decision-making based on the findings of this examination.

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.

Obstructive Sleep Apnea Among Gravidas With Chronic Hypertension Compared to Matched Controls: A Prospective Cohort Study.

BACKGROUND: Previous studies of obstructive sleep apnea (OSA) risk in gravidas with chronic hypertension (cHTN) did not control for obesity as a risk factor for OSA. We therefore performed this study to evaluate whether OSA is more prevalent among gravidas with cHTN compared to normotensive gravidas matched for body mass index (BMI) and gestational age (primary outcome). We also assessed whether OSA is more severe when comorbid with cHTN in pregnancy (secondary outcome). METHODS: This was a single-center, prospective cohort study. Adult gravidas at 10-20 weeks of gestation, with and without cHTN, were enrolled and BMI matched. All subjects answered OSA screening questionnaires and underwent a home sleep test when they were between 10 and 20 weeks of gestation. Pregnancy outcomes were followed for all subjects. We performed univariable and multivariable logistic regression to model the relationship between cHTN status and OSA. RESULTS: A total of 100 pregnant subjects (50 with cHTN and 50 normotensive) completed a home sleep test of 2 hours or more. There were no differences in demographic variables between the 2 groups, except that gravidas with cHTN were significantly older than normotensive subjects (mean ± standard deviation [SD] 34 ± 4 vs 30 ± 6 years; P < .001). OSA was more prevalent (64% vs 38%; P = .009; odds ratio [95% confidence interval (CI)] 2.90 [1.30-6.65]; P = .01) and more severe in gravidas with cHTN (moderate or severe OSA 59% vs 21%; P = .009). After controlling for age, we found no overall association between cHTN on OSA risk (adjusted odds ratio [95% CI] 2.22 [0.92-5.40]; P = .076). However, among gravidas older than 25 years of age, cHTN was associated with higher odds of OSA (adjusted odds ratio [95% CI], 2.64 [1.06-6.71], P = .038). CONCLUSIONS: cHTN and age are important risk factors for OSA in gravidas. Gravidas with cHTN should be screened for OSA in early pregnancy. Future studies may validate screening tools that include cHTN and age, and investigate the role of OSA therapy in blood pressure control.

Anesthesia and Analgesia for the Obese Parturient.

Obesity is a worldwide epidemic and is associated with an increased risk of hypertension, diabetes, and obstructive sleep apnea. Pregnant patients with obesity experience a higher risk of maternal and fetal complications. Anesthesia also poses higher risks for obese parturients and may be more technically challenging due to body habitus. Safe anesthesia practice for these patients must take into consideration the unique challenges associated with the combination of pregnancy and obesity.

Postpartum Respiratory Depression.

Postpartum respiratory depression is a complex, multifactorial issue that encompasses a patient's baseline preexisting conditions, certain pregnancy-specific conditions or complications, as well as the iatrogenic element of various medications given in the peripartum period. In this review, we discuss many of these factors including obesity, sleep-disordered breathing, chronic lung disease, neuromuscular disorders, opioids, preeclampsia, peripartum cardiomyopathy, postpartum hemorrhage, amniotic fluid embolism, sepsis, acute respiratory distress syndrome (ARDS), and medications such as analgesics, sedatives, anesthetics, and magnesium. Current recommendations for screening, treatment, and prevention are also discussed.

Dexamethasone as an Analgesic Adjunct for Postcesarean Delivery Pain: A Randomized Controlled Trial.

OBJECTIVES: Dexamethasone has been shown to have analgesic properties in the general surgical population. However, the analgesic effects for women that undergo cesarean deliveries under spinal anesthesia remain unclear and may be related to the timing of dexamethasone administration. We hypothesized that intravenous dexamethasone administered before skin incision would significantly reduce postoperative opioid consumption at 24 h after cesarean delivery under spinal anesthesia with intrathecal morphine. METHODS: Women undergoing elective cesarean deliveries under spinal anesthesia were randomly assigned to receive 8 mg of intravenous dexamethasone or placebo prior to skin incision. Both groups received a standardized spinal anesthetic and multimodal postoperative analgesic regime. The primary outcome was cumulative opioid consumption at 24 h. Secondary outcomes included cumulative opioid consumption at 48 h, time to first analgesic request, and pain scores at rest and on movement at 2, 24, and 48 h. RESULTS: 47 patients were analyzed-23 subjects that received dexamethasone and 24 subjects that received placebo. There was no difference in the median (Q1, Q3) cumulative opioid consumption in the first 24 hours following cesarean delivery between the dexamethasone group {15 (7.5, 20.0) mg} and the placebo group {13.75 (2.5, 31.25) mg} (P=0.740). There were no differences between the groups in cumulative opioid consumption at 48 h, time to first analgesic request, and pain scores. CONCLUSIONS: Intravenous dexamethasone 8 mg administered prior to skin incision did not reduce the opioid consumption of women that underwent cesarean deliveries under spinal anesthesia with intrathecal morphine and multimodal postoperative analgesic regimen.

Ropivacaine and Ketorolac Wound Infusion for Post-Cesarean Delivery Analgesia: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the efficacy of wound infusion with ropivacaine plus ketorolac compared with placebo for post-cesarean delivery analgesia in women who received a multimodal analgesic regimen including intrathecal morphine. METHODS: In a randomized double-blind study, women undergoing scheduled cesarean delivery under spinal or combined spinal epidural anesthesia were randomized to wound infusion with ropivacaine 0.2% plus ketorolac, or saline placebo using an elastometric pump for 48 hours. The primary outcome was pain score with movement at 24 hours after surgery (0-10 scale, 0=no pain and 10=worst possible pain). Secondary outcomes included pain scores at rest at 24 hours, pain scores at rest and with movement at 2 and 48 hours, opioid consumption, and time to first rescue analgesic. A sample size of 35 per group (n=70) was planned. RESULTS: From November 8, 2016, to May 17, 2019, 247 women were screened, and 71 completed the study per protocol: 38 in the placebo group and 33 in the ropivacaine plus ketorolac group. Patient demographics and intraoperative characteristics were comparable between the groups. There was no significant difference between the groups in the primary outcome of pain score with movement at 24 hours (difference in median score 0, 95% CI -1 to 2, P=.94). There were also no significant differences between the placebo and ropivacaine plus ketorolac groups in pain scores at other time points, in total opioid consumption (difference in median consumption -12.5 mg, 95% CI -30 to 5, P=.11), or in time to rescue analgesics (median [interquartile range] 660 [9-1,496] vs 954 [244-1,710] minutes, hazard ratio 0.69, 95% CI 0.41 to 1.17, P=.16). CONCLUSION: There was no benefit of wound infusion with ropivacaine and ketorolac in women who received intrathecal morphine and a multimodal analgesic regimen. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02829944. FUNDING SOURCE: The study was supported in part by Avanos Medical Inc.

Obesity And Obstetric Anesthesia: Current Insights.

Obesity is a significant global health problem. It results in a higher incidence of complications for pregnant women and their neonates. Cesarean deliveries are more common in obese parturients as well. The increased burden of comorbidities seen in this population, such as obstructive sleep apnea, necessitates antepartum anesthetic consultation. These patients pose unique challenges for the practicing anesthesiologist and may benefit from optimization prior to delivery. Complications from anesthesia and overall morbidity and mortality are higher in this population. Neuraxial anesthesia can be challenging to place in the obese parturient, but is the preferred anesthetic for cesarean delivery to avoid airway manipulation, minimize aspiration risk, prevent fetal exposure to volatile anesthetic, and decrease risk of post-partum hemorrhage from volatile anesthetic exposure. Monitoring and positioning of these patients for surgery may pose specific challenges. Functional labor epidural catheters can be topped up to provide conditions suitable for surgery. In the absence of a working epidural catheter, a combined spinal epidural anesthetic is often the technique of choice due to relative ease of placement versus a single shot spinal technique as well as the ability to extend the anesthetic through the epidural portion. For cesarean delivery with a vertical supraumbilical skin incision, a two-catheter technique may be beneficial. Concern for thromboembolism necessitates early mobilization and a multimodal analgesic regimen can help accomplish this. In addition, thromboprophylaxis is recommended in this population after delivery-especially cesarean delivery. These patients also need close monitoring in the post-partum period when they are at increased risk for several complications.

Screening extremely obese pregnant women for obstructive sleep apnea.

BACKGROUND: Obesity is prevalent among pregnant women in the United States; obstructive sleep apnea is highly comorbid with obesity and is associated with adverse pregnancy outcomes. Screening for obstructive sleep apnea in pregnant women has remained a challenge because of a lack of validated screening tools. OBJECTIVE: The purpose of this study was to evaluate established obstructive sleep apnea screening tools, a sleepiness scale, and individual component items in a cohort of pregnant women with extreme obesity in mid pregnancy with the use of objective testing to determine obstructive sleep apnea status and to describe the prevalence of obstructive sleep apnea among women with extreme obesity. STUDY DESIGN: Adult pregnant subjects, between 24 and 35 weeks gestation, with a body mass index ≥40 kg/m2 at the time of enrollment completed obstructive sleep apnea screening tools (Berlin Questionnaire, American Society of Anesthesiologists checklist, and STOP-BANG questionnaire) and the Epworth Sleepiness Scale; they also underwent physical examination of the neck, mouth, and airway. The published obstructive sleep apnea in pregnancy prediction score was calculated for each subject. Obstructive sleep apnea status for each subject was determined by the results of an overnight, unattended type III home sleep apnea test. RESULTS: Twenty-four percent of pregnant women with extreme obesity had obstructive sleep apnea on home sleep apnea testing in mid pregnancy (Apnea-Hypopnea Index, ≥5 events per hour]. Established obstructive sleep apnea screening tools performed very poorly to screen for obstructive sleep apnea in this cohort. Age, body mass index, neck circumference, frequently witnessed apneas, and highly likely to fall asleep while driving were associated most strongly with obstructive sleep apnea status in this cohort. CONCLUSION: We found that 24% of pregnant women with body mass index ≥40 kg/m2 between 24 and 35 weeks gestation have obstructive sleep apnea, defined as Apnea-Hypopnea Index ≥5 events per hour on an overnight type III home sleep apnea test. We found the Berlin Questionnaire, American Society of Anesthesiologists checklist, STOP-BANG, obstructive sleep apnea in pregnancy score by Facco et al, and the Epworth Sleepiness Scale were not useful screening tools for obstructive sleep apnea in a cohort of obese pregnant women. However, age, body mass index, neck circumference, frequently witnessed apneas, and likely to fall asleep while driving were associated with obstructive sleep apnea in this cohort. Further studies are needed to adjust the criteria and thresholds within the available screening tools to better predict obstructive sleep apnea in pregnant women with obesity.

A review of the associations between obstructive sleep apnea and hypertensive disorders of pregnancy and possible mechanisms of disease.

Obesity is prevalent among pregnant women in the United States; 15-20% of obese pregnant women have obstructive sleep apnea. The prevalence of obstructive sleep apnea increases along with body mass index, age and in the presence of other co-morbidities. Untreated obstructive sleep apnea in women is associated with a range of cardiovascular, pulmonary and metabolic co-morbidities; recent studies suggest that women with obstructive sleep apnea in pregnancy may be at significantly greater risk of entering pregnancy with chronic hypertension and/or of developing hypertensive disorders of pregnancy: gestational hypertension; preeclampsia; or eclampsia. This has serious public health implications; hypertensive disorders of pregnancy are a major cause of maternal and neonatal morbidity and mortality and are associated with a greater lifetime risk for cardiovascular disease. The mechanisms that associated obstructive sleep apnea with hypertensive disorders of pregnancy have not been defined, but several pathways are scientifically plausible. In this review, we will present a comprehensive literature review of the following: the associations between obstructive sleep apnea and hypertensive disorders of pregnancy; the proposed mechanisms that may connect obstructive sleep apnea and hypertensive disorders of pregnancy; and the effectiveness of treatment at mitigating these adverse outcomes.

Management of Obstructive Sleep Apnea in Pregnancy.

The spectrum of sleep-disordered breathing (SDB) ranges from mild snoring to obstructive sleep apnea, the most severe form of SDB. Current recommendations are to treat these women with continuous positive airway pressure despite limited data. SDB in early and mid-pregnancy is associated with preeclampsia and gestational diabetes. Pregnant women with a diagnosis of obstructive sleep apnea at delivery were at significantly increased risk of having cardiomyopathy, congestive heart failure, pulmonary embolism, and in-hospital death. These effects were exacerbated in the presence of obesity. Postpartum, these women are at risk for respiratory suppression and should be monitored.

Obstructive Sleep Apnea in Pregnant Women: A Review of Pregnancy Outcomes and an Approach to Management.

Among obese pregnant women, 15%-20% have obstructive sleep apnea (OSA) and this prevalence increases along with body mass index and in the presence of other comorbidities. Prepregnancy obesity and pregnancy-related weight gain are certainly risk factors for sleep-disordered breathing in pregnancy, but certain physiologic changes of pregnancy may also increase a woman's risk of developing or worsening OSA. While it has been shown that untreated OSA in postmenopausal women is associated with a range of cardiovascular, pulmonary, and metabolic comorbidities, a body of literature is emerging that suggests OSA may also have serious implications for the health of mothers and fetuses during and after pregnancy. In this review, we discuss the following: pregnancy as a vulnerable period for the development or worsening of OSA; the associations between OSA and maternal and fetal outcomes; the current screening modalities for OSA in pregnancy; and current recommendations regarding peripartum management of OSA.

A randomized trial of phenylephrine infusion versus bolus dosing for nausea and vomiting during Cesarean delivery in obese women.

PURPOSE: Hypotension is common after spinal anesthesia for Cesarean delivery. It is associated with nausea, vomiting, and fetal acidosis. Previous research on phenylephrine excluded obese subjects. We compared the incidence of intraoperative nausea and vomiting (IONV) in obese patients who received a prophylactic phenylephrine infusion vs those who received bolus dosing for the treatment of spinal-induced hypotension. METHODS: In this multicentre, double-blinded randomized controlled trial, 160 obese women undergoing elective Cesarean delivery under spinal anesthesia were randomized to receive a prophylactic phenylephrine infusion initiated at 50 µg·min-1 (and titrated according to a predefined algorithm) or 100 µg phenylephrine boluses to treat hypotension. Maternal systolic blood pressure was maintained within 20% of baseline. The primary study outcome was the incidence of IONV. RESULTS: Intraoperative nausea and vomiting were significantly reduced in the infusion group compared to the bolus group (46% vs 75%, respectively; relative risk [RR], 0.61; 95% confidence interval [CI], 0.47 to 0.80; P < 0.001). This was associated with significantly reduced need for intraoperative rescue antiemetics (26% vs 42%, respectively; RR, 0.62; 95% CI, 0.40 to 0.97; P = 0.04), but no difference in the incidence of vomiting. Postoperative vomiting at two hours was reduced in the infusion group (11% vs 25%; RR, 0.44; 95% CI, 0.21 to 0.90; P = 0.02);however, there were no differences in the incidence or severity of postoperative nausea, need for rescue antiemetics at two hours and 24 hr, or the incidence of postoperative vomiting at 24 hr. CONCLUSION: In obese women undergoing Cesarean delivery with spinal anesthesia, prophylactic phenylephrine infusion was associated with less intraoperative nausea, less need for rescue antiemetics, and reduced early postoperative vomiting. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT01481740). Registered 22 July 2011.

Blood-Conservation Strategies in a Blood-Refusal Parturient with Placenta Previa and Placenta Percreta.

Abnormal placentation can be associated with significant blood loss and massive blood transfusions. Caring for parturients with abnormal placentation who refuse blood transfusion is very challenging. We present a 35-year-old, gravida 3, para 1, Jehovah's Witness at 35 weeks of gestation with placenta percreta, who underwent cesarean delivery and delayed hysterectomy. A multidisciplinary team developed a plan, including the use of perioperative erythropoietin and IV iron dextran, intraoperative acute normovolemic hemodilution, cell salvage, tranexamic acid, and uterine artery embolization. This strategy was successful in avoiding the need for allogeneic transfusion and ensuring an uneventful recovery after both surgical procedures.

A retrospective assessment of the incidence of respiratory depression after neuraxial morphine administration for postcesarean delivery analgesia.

Respiratory depression can occur after neuraxial morphine administration. In the obstetric population, there are little data on respiratory depression after neuraxial morphine administration in women undergoing cesarean delivery. In this single-center, retrospective study in 5036 obstetric patients (mean body mass index = 34 kg/m) who underwent cesarean delivery and received neuraxial morphine, we did not identify any instances of respiratory depression requiring naloxone administration or rapid response team involvement. Therefore, the upper 95% confidence limit for respiratory depression in our study is 0.07% (1 event per 1429 cases).

Prophylaxis and treatment of the side-effects of neuraxial morphine analgesia following cesarean delivery.

PURPOSE OF REVIEW: Neuraxial morphine is commonly used for analgesia after cesarean delivery, but is frequently associated with postoperative nausea and vomiting (PONV) and pruritus. This review describes the recent advances in the management of those side-effects. RECENT FINDINGS: Neuraxial-morphine-induced side-effects are dose related; therefore, the minimum effective dose should be used. Dexamethasone, 5HT3 receptor antagonists, antihistamines, and anticholinergics reduce the incidence of PONV, whereas metoclopramide 10 mg does not appear to be effective for PONV prophylaxis in this patient population. Combination antiemetic therapy provides improved prophylaxis compared with monotherapy, but has seldom been studied in women undergoing cesarean delivery with neuraxial morphine. Studies of P6 acupressure reported inconsistent results. Polymorphism of the µ-opioid receptor may affect the severity of neuraxial-morphine-induced pruritus. Opioid antagonists and mixed agonist/antagonists appear to be the most useful for the management of opioid-induced pruritus. Prophylactic 5HT3 receptor antagonists and dexamethasone do not seem to be effective for reducing the incidence of pruritus. In contrast, ondansetron, pentazocine, and dimenhydrinate may be useful for treating established pruritus. SUMMARY: PONV and pruritus are frequent side-effects of neuraxial morphine. Future studies investigating combination antiemetic therapy, long-acting antiemetics, and strategies to manage pruritus are needed.

Leptin levels and luteinizing hormone pulsatility in normal cycling women and their relationship to daily changes in metabolic rate.

OBJECTIVE: To determine whether leptin and LH secretion in normal women is related to changes in metabolic rate. SETTING: Academic medical center. PATIENT(S) AND DESIGN: Ten young women with normal weight and menses were studied during the early follicular phase. Leptin and LH levels were sampled every 15 minutes over a 24-hour period. Metabolic rate was frequently sampled using indirect calorimetry. Luteinizing hormone pulsatility was analyzed using a Cluster Program analysis. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Leptin, LH, and metabolic rate levels. RESULT(S): All subjects demonstrated a diurnal leptin curve. Luteinizing hormone pulses were increased in amplitude and slower after the leptin peak. The average (+/-SE) number of LH pulses per 6 hours slowed from 4.30 +/- 0.42 to 3.00 +/- 0.42 pulses after the leptin peak, whereas pulse amplitude increased from 1.64 +/- 0.26 to 2.51 +/- 0.42 mIU/mL after the leptin peak. The LH interpulse interval increased from 85.1 +/- 3.64 minutes to 108.8 +/- 10.26 minutes after the leptin peak. Metabolic rate began to drop approximately 4-6 hours before leptin levels peaked, going from 1.66 +/- 0.24 to 1.15 +/- 0.04 kcal/min after the leptin peak. CONCLUSION(S): There is a significant association between the timing of the leptin peak, the nightly slowing of LH pulses, and the fall in metabolic rate, suggesting a metabolic cycle in normal individuals.

Use of alternative therapies in menopause.

Hormone replacement therapy has traditionally been used to treat the accompanying symptoms of oestrogen deficiency in menopause. However, not all women can, or prefer to, receive this treatment and alternatives should be considered to reduce the increased risk of osteoporosis and heart disease in menopausal women. This chapter reviews the current literature on the efficacy of phyto-oestrogens in preventing cardiovascular disease, various cancers and osteoporosis, as well as treating the vasomotor and other menopause-related symptoms. Select herbal therapies, as well as selective oestrogen receptor modulators, are also considered.