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OBJECTIVE: Fetal cardiac anomalies are the most commonly diagnosed structural anomalies. In these cases, Maternal-Fetal Medicine (MFM) specialists are tasked with counseling patients on a spectrum of diagnoses as well as their prognostic implications. A recent study of pediatric cardiologists demonstrated that personal beliefs regarding termination impact the counseling provided to patients. Our objective was to study whether the personal beliefs of MFMs impact counseling of patients with severe fetal cardiac anomalies and to compare these providers to their cardiology counterparts. METHODS: We conducted an anonymous cross-sectional survey of MFMs in New England that assessed personal beliefs and counseling practices when diagnosing hypoplastic left heart syndrome (HLHS). We subsequently compared these providers to the previously surveyed cardiologists. RESULTS: A total of 34 respondents representing a broad spectrum of age and experience across several states in New England were analyzed. When presented with the statement "some life is always better than no life at all," 79% (n = 27) of respondents disagreed and all respondents (n = 34) offered termination, palliative care, and treatment options when counseling patients with HLHS. Additionally, while 74% (n = 25) of providers would personally support a decision to terminate a pregnancy with HLHS, 94% (n = 32) would professionally support the decision to pursue termination.MFMs and cardiologists differed in their responses to "some life is better than no life" and the belief that termination should be offered, though differences did not reach statistical significance. However, with respect to the providers' personal and professional support of the decision to terminate the pregnancy, the groups of respondents varied significantly in their level of support, both professionally and personally with fewer cardiologists supporting this decision. CONCLUSION: When diagnosing a severe and potentially fatal congenital cardiac anomaly, counseling by MFMs was largely unaffected by personal beliefs regarding termination of pregnancy. While this is consistent with previously published data on counseling practices among pediatric cardiology specialists, some important differences between the specialties were seen.

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OBJECTIVE: Percent glycated albumin (%GAlb) is a marker of glycemia over the past 2 to 3 weeks in nonpregnant individuals. Longitudinal changes in %GAlb extending throughout pregnancy and postpartum (PP) have not been described. We aimed to describe levels of %GAlb throughout pregnancy and PP and relationships with glycemia. STUDY DESIGN: Fifty women among those in the Study of Pregnancy Regulation of INsulin and Glucose cohort underwent 75-g oral glucose tolerance tests (OGTTs) at a mean of 13 weeks (V1) and 26 weeks (V2) of gestation and 11 weeks' PP. %GAlb was measured on frozen plasma samples. RESULTS: Total albumin decreased from V1 to V2 and increased PP to levels higher than at V1. %GAlb declined between V1 and V2 (ß = - 0.63% 95% CI [-0.8, -0.6] p < 0.001) and remained stable between V2 and PP (ß = - 0.04% [-0.3, 0.2] p = 0.78). Body mass index (BMI) was inversely related to %GAlb in pregnancy (V1: rho = - 0.5, p = 0.0001; V2 rho = - 0.4, p = 0.006), but not PP (rho = - 0.15, p = 0.31). The longitudinal changes in %GAlb persisted after adjusting for BMI. Neither glycemia measurements nor hemoglobin A1c were associated with %GAlb at any time point, and adjustments for BMI did not reveal additional associations. CONCLUSION: %GAlb decreases between early and late gestation and remains decreased PP, despite a PP increase in total albumin above early pregnancy values. Given the lack of correlation with OGTT values or A1c, %GAlb is unlikely to be useful in assessing glycemia in pregnant or PP women. KEY POINTS: · Changes in %GAlb extending to the postpartum period have not been described.. · %GAlb decreases in pregnancy and remains decreased postpartum, despite a postpartum increase in total albumin above early pregnancy values.. · Glycemia measurements nor A1c were associated with %GAlb at any time point, therefore, %GAlb is unlikely to be useful in assessing glycemia in pregnant or postpartum women..

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Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease often associated with other cardiac defects. The adaptations and physiologic changes in pregnancy can present maternal challenges and complications; multidisciplinary care allows for the safest management of pregnancy and delivery in these patients. We present a case of the anesthetic management of cesarean delivery in a woman with CCTGA with her pregnancy complicated by recurrent volume overload, pulmonary hypertension, and dysrhythmias.

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Institutional policies restricting pregnant providers from caring for patients receiving inhaled epoprostenol exist across the nation based on little to no data to substantiate this practice. Over the last 2 decades, the use of inhaled pulmonary vasodilators has expanded in patients with cardiac and respiratory disease providing more evidence for the safety of these medications in obstetrical patients. We propose a thoughtful consideration and review of the literature to remove this restriction to reduce the need to reveal early pregnancy status to employers, to alleviate undue stress for pregnant caregivers who are exposed to patients receiving epoprostenol, and to ensure safe, equal employment, and learning opportunities for pregnant providers.

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CONTEXT: The American Diabetes Association (ADA) recommends a 3-day preparatory diet prior to a diagnostic oral glucose tolerance test (OGTT), a test often recommended in postpartum individuals with a history of gestational diabetes (GDM). OBJECTIVE: Evaluate the relationship between carbohydrate intake and OGTT glucose in 2 cohorts of postpartum individuals. METHODS: We performed analyses of postpartum individuals from 2 prospective studies with recent GDM (Balance after Baby Intervention, BABI, n = 177) or risk factors for GDM (Study of Pregnancy Regulation of INsulin and Glucose, SPRING, n = 104) .We measured carbohydrate intake using 24-hour dietary recalls (SPRING) or Food Frequency Questionnaire (BABI) and performed 2-hour 75-g OGTTs. The main outcome measure was 120-minute post-OGTT glucose. RESULTS: There was no relationship between carbohydrate intake and 120-minute post-OGTT glucose level in either study population (SPRING: ß = 0.03, [-5.5, 5.5] mg/dL, P = .99; BABI: ß = -3.1, [-9.5, 3.4] mg/dL, P = .35). Adding breastfeeding status to the model did not change results (SPRING ß = -0.14, [-5.7, 5.5] mg/dL, P = .95; BABI ß = -3.9, [-10.4, 2.7] mg/dL, P = .25). There was, however, an inverse relationship between glycemic index and 120-minute post OGTT glucose (BABI: ß = -1.1, [-2.2, -0.03] mg/dL, P = .04). CONCLUSION: Carbohydrate intake is not associated with post-OGTT glucose levels among postpartum individuals. Dietary preparation prior to the OGTT may not be necessary in this population.

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Data acquired by a dense seismic network deployed in the Cerdanya basin (Eastern Pyrenees) is used to track the temporal and spatial evolution of meteorological events such as rainfall episodes or thunderstorms. Comparing seismic and meteorological data, we show that for frequencies above 40 Hz, the dominant source of seismic noise is rainfall and hence the amplitude of the seismic data can be used as a proxy of rainfall. The interstation distance of 1.5 km provides an unprecedented spatial resolution of the evolution of rainfall episodes along the basin. Two specific episodes, one dominated by stratiform rain and the second one dominated by convective rain, are analyzed in detail, using high resolution disdrometer data from a meteorological site near one of the seismic instruments. Seismic amplitude variations follow a similar evolution to radar reflectivity values, but in some stratiform precipitation cases, it differs from the radar-derived precipitation estimates in this region of abrupt topography, where radar may suffer antenna beam blockage. Hence, we demonstrate the added value of seismic data to complement other sources of information such as rain-gauge or weather radar observations to describe the evolution of ground-level rainfall fields at high spatial and temporal resolution. The seismic power and the rainfall intensity have an exponential relationship and the periods with larger seismic power are coincident. The time intervals with rain drops diameters exceeding 3.5 mm do not result in increased seismic amplitudes, suggesting that there is a threshold value from which seismic data are no longer proportional to the size of the drops. Thunderstorms can be identified by the recording of the sonic waves generated by thunders, with. Single thunders detected to distances of a few tens of kilometers. As the propagation of these acoustic waves is expected to be strongly affected by parameters as air humidity, temperature variations or wind, the seismic data could provide an excellent tool to investigate atmospheric properties variations during thunderstorms.

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OBJECTIVE: Poor attendance at the 6-week postpartum (PP) visit has been well reported. Attendance at this visit is crucial to identify women who have persistent diabetes mellitus (DM) following pregnancies affected by gestational DM (GDM). The medical home model has eliminated barriers to care in various other settings. This study sought to improve PP attendance among women with GDM by jointly scheduling PP visits and the 2-month well infant visits. STUDY DESIGN: All patients with a diagnosis of GDM who received care at a New York City-based publicly insured hospital clinic and delivered between October 2017 and June 2019 were eligible. Data were obtained via chart review. The primary outcome was attendance at the PP visit compared with previously published historical controls. Secondary outcomes were rates of PP glucose screening and well infant attendance. RESULTS: Of the 74 patients enrolled, 41.9% were Hispanic and 17.6% were Black, mean age was 31.6 years, and 58.1% delivered vaginally. Attendance at the 6-week PP visit was 68.9%, and attendance at the infant visit was 55.1%. PP glucose testing was ordered for 76.5% of attendees at the PP visit, and of those ordered, 43.6% of attendees completed testing. All patients had joint visits requested, though only 70.3% of visits were scheduled jointly. Among those who were jointly scheduled, 71.2% of women attended, 57.7% of infants attended, and 7.7% of pairs attended on the same day. The PP visit attendance rate was not significantly different than the prior attendance rate (p = 0.84). CONCLUSION: This study was unable to improve PP visit attendance among women with GDM by jointly scheduling the 6-week PP visit and the 2-month well-infant visit. Future research could be directed toward a shared space where both women and children can be seen to attempt to increase PP visit attendance and monitoring for women with GDM. KEY POINTS: · Attendance at the PP visit is poor, and without a visit, women with pregnancies affected by gestational diabetes remain unscreened for PP dysglycemia.. · Jointly scheduling women and their infants to eliminate barriers to care studied by this group, however, were unable to improve attendance.. · Innovative strategies are needed to improve PP attendance among women with pregnancies affected by GDM..

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BACKGROUND: Intrahepatic cholestasis of pregnancy is associated with a significant risk of stillbirth, which contributes to variation in clinical management. Recent Society for Maternal-Fetal Medicine guidance recommends delivery at 36 weeks of gestation for patients with serum bile acid levels of >100 µmol/L, consideration for delivery between 36 and 39 weeks of gestation stratified by bile acid level, and against preterm delivery for those with clinical features of cholestasis without bile acid elevation. OBJECTIVE: This study aimed to investigate institutional practices before the publication of the new delivery timing recommendations to establish the maternal and neonatal effects of late preterm, early-term, and term deliveries in the setting of cholestasis. STUDY DESIGN: This study examined maternal and neonatal outcomes of 441 patients affected by cholestasis delivering 484 neonates in a 4-hospital system over a 30-month period. Logistic and linear regression analyses were performed to assess neonatal outcomes concerning peak serum bile acid levels at various gestational ages controlling for maternal comorbidities, multiple pregnancies, and neonatal birthweight. RESULTS: With the clinical flexibility afforded by the new guidelines, pregnancy prolongation to term may have been achieved in 91 patients (21%), and 286 patients (74%) with bile acid elevation could have delivered at a later gestational age. Preterm deliveries of patients with bile acid levels of >10 µmol/L were associated with higher rates of neonatal intensive care unit admission and adverse neonatal outcomes than early-term deliveries. CONCLUSION: Study data suggested an opportunity for education and practice change to reflect current Society for Maternal-Fetal Medicine guidelines in efforts to reduce potential neonatal morbidities associated with late preterm deliveries among pregnancies affected by cholestasis.

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OBJECTIVE: Fetal growth restriction (FGR) is associated with poor neonatal outcomes and stillbirth, and screening via fundal height or ultrasound is routinely performed. During the novel coronavirus disease 2019 (COVID-19) pandemic, we developed a hybrid model of prenatal care which decreased the frequency of in-person visits and incorporated telemedicine visits. We sought to determine if prenatal FGR diagnoses decreased with this hybrid model compared with routine prenatal care. STUDY DESIGN: This was a retrospective cohort study of singleton nonanomalous neonates with birth weights <10th percentile at term. The "routine care" group was consisted of those who born between April and July 2019 with in-person prenatal care, and the "hybrid care" group was consisted of those who born between April and July 2020 with both in-person and telemedicine prenatal cares at a collaborative academic practice. The primary outcome was the rate of diagnosis of small for gestational age (SGA) as defined as infant birth weight <10th percentile without a prenatal diagnosis of FGR. The secondary outcome was timing of diagnosis of FGR. RESULTS: Overall, 1,345 and 1,296 women gave birth in the routine and hybrid groups, respectively. The number of in-person prenatal care visits decreased from 15,024 in the routine period to 7,727 in the hybrid period; 3,265 telemedicine visits occurred during the hybrid period. The total number of prenatal patients remained relatively stable at 3,993 and 3,753 between periods. Third trimester ultrasounds decreased from 2,929 to 2,014 between periods. Birth weights <10 percentile occurred in 115 (8.6%) births during the routine period and 79 (6.1%) births during the hybrid period. Of 115, 44 (38.3%) cases were prenatally diagnosed with FGR in the routine versus 28 of 79 (35.4%) in the hybrid group (p = 0.76). Median gestational age at diagnosis did not vary between groups (36 vs. 37 weeks, p = 0.44). CONCLUSION: A hybrid prenatal care model did not alter the detection of FGR. Future efforts should further explore the benefits of incorporating telemedicine into prenatal care. KEY POINTS: · Telemedicine visits can provide comprehensive prenatal care.. · FGR was diagnosed equally with hybrid versus routine prenatal care.. · FGR diagnosis was not delayed with hybrid care..

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BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare but serious complication in pregnancy that places the mother and fetus at high risk for morbidity and mortality. This case illustrates novel pregnancy complications associated with this rare medical condition. CASE PRESENTATION: A 31-year-old G3P0020 at 28 weeks and 1 day was admitted with severe thrombocytopenia and was ultimately diagnosed with TTP. With therapeutic plasma exchange (TPE), maternal status improved. At 28 weeks 6 days, however, non-reassuring fetal testing prompted cesarean delivery with placental abruption noted intraoperatively. Pathology examination confirmed placental abruption and also revealed multiple placental infarcts. CONCLUSION: While medical management of TTP can significantly improve the health of the mother, this case highlights the potential role of TTP in abruption and other placental pathology and thus, the need for close fetal surveillance throughout an affected pregnancy.

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Antecedentes y objetivos: El dolor crónico oncológico es una experiencia compleja que resulta de la interacción de múltiples factores. Identificar qué factores juegan un papel importante en la configuración de esta experiencia permitiría reducir sus efectos. El objetivo fundamental de este trabajo era identificar qué factores están relacionados con la cronificación del dolor oncológico, a juicio de un grupo de expertos. Y de forma secundaria, se trataba de explorar qué factores podrían actuar de protectores. Material y método: Se invitó a un grupo multidisciplinar de expertos en oncología. Se utilizó la metodología Delphi como forma de llegar al consenso entre los expertos participantes. Resultados: Dos rondas fueron suficientes para alcanzar el consenso. Un total de 22 expertos participaron en ambas rondas. Los principales factores de riesgo identificados fueron: el proceso oncológico, el dolor mal controlado y los factores psicológicos, particularmente el catastrofismo. Entre los factores protectores destacaron: soporte social, tratamiento precoz del dolor, personalidad optimista y adherencia al tratamiento. Conclusiones: Este estudio contribuye a identificar los principales factores que pueden contribuir a la cronificación del dolor oncológico, también aporta información sobre potenciales protectores. Si se confirman por investigaciones futuras, estos resultados pueden ayudar a desarrollar instrumentos diagnósticos específicos con los que identificar las personas en situación de riesgo, así como a crear programas preventivos

Background and objectives: Chronic cancer pain is a complex experience that results from the interaction of multiple factors. Identifying which factors play an important role in shaping this experience would reduce its effects. The main objective of this study was to identify which factors are related to the chronification of cancer pain, in the opinion of a group of experts. And secondarily, to explore which factors might act as protectors. Material and methods: A multidisciplinary group of experts in oncology from various fields was invited. The Delphi methodology was used as a way to reach consensus among the participating experts. Results: Two rounds were enough to reach consensus. A total of 22 experts participated in both rounds. The main risk factors were the oncological process, a poorly controlled pain, and psychological factors, particularly pain catastrophic thinking. Among the main protective factors there were: social support, early pain treatment, optimism, and adherence to treatment. Conclusions: This study contributes to identifying the main factors that can contribute to the chronification of cancer pain, and also provides information on potential protectors. If confirmed by future research, these results can help develop specific diagnostic tools to help identify people at risk, as well as create preventive programs

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BACKGROUND: Recruitment manoeuvres generate a transient increase in trans-pulmonary pressure that could open collapsed alveoli. Recruitment manoeuvres might generate very high inspiratory airflows. We evaluated whether recruitment manoeuvres could displace respiratory secretions towards the distal airways and impair gas exchange in a porcine model of bacterial pneumonia. METHODS: We conducted a prospective randomised study in 10 mechanically ventilated pigs. Pneumonia was produced by direct intra-bronchial introduction of Pseudomonas aeruginosa. Four recruitment manoeuvres were applied randomly: extended sigh (ES), maximal recruitment strategy (MRS), sudden increase in driving pressure and PEEP (SI-PEEP), and sustained inflation (SI). Mucus transport was assessed by fluoroscopic tracking of radiopaque disks before and during each recruitment manoeuvre. The effects of each RM on gas exchange were assessed 15 min after the intervention. RESULTS: Before recruitment manoeuvres, mucus always cleared towards the glottis. Conversely, mucus was displaced towards the distal airways in 28.6% ES applications and 50% of all other recruitment manoeuvres (P=0.053). Median mucus velocity was 1.26 mm min-1 [0.48-3.89] before each recruitment manoeuvre, but was reversed (P=0.007) during ES [0.10 mm min-1 [-0.04-1.00]], MRS [0.10 mm min-1 [-0.4-0.48]], SI-PEEP [0.02 mm min-1 [-0.14-0.34]], and SI [0.10 mm min-1 [-0.63-0.75]]. When PaO2 failed to improve after recruitment manoeuvre, mucus was displaced towards the distal airways in 68.7% of the cases, compared with 31.2% recruitment manoeuvres associated with improved PaO2 (odds ratio: 4.76 (95% confidence interval: 1.13-19.97). CONCLUSIONS: Recruitment manoeuvres dislodge mucus distally, irrespective of airflow generated by different recruitment manoeuvres. Further investigation in humans is warranted to corroborate these pre clinical findings, as there may be limited benefits associated with lung recruitment in pneumonia.

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Objective: To determine risk factors for a positive postpartum depression screen among women with private health insurance and 24/7 access to care.Study design: Retrospective cohort study of all patients delivered by a single MFM practice from April 2015 to September 2016. All patients had private health insurance and 24/7 access to care. All patients were scheduled to undergo the Edinburgh Postnatal Depression Scale (EPDS) at their 6-week postpartum visit and a positive screen was defined as a score of 10 or higher, or a score greater than zero on question 10 (thoughts of selfharm). Using logistic regression, risk factors for postpartum depression were compared between women with and without a positive screen.Results: Of the 1237 patients delivered, 1113 (90%) were screened with the EPDS. 81 patients (7.3, 95%CI 5.9-9.0%) of those tested had a positive screen. On regression analysis, risk factors associated with a positive screen were nulliparity (aOR 1.8, 95%CI 1.1, 2.9), cesarean delivery (aOR 1.7, 95%CI 1.1, 2.8), non-White race (aOR 2.0, 95%CI 1.1, 3.5), and a history of depression or anxiety (aOR 4.6, 95%CI 2.6, 8.1). Among the 100 women with a history of depression or anxiety, selective serotonin reuptake inhibitor (SSRI) use in the postpartum period was not associated with a reduced risk of a positive screen (25.5% in those taking an SSRI versus 18.4% of those not taking an SSRI, p = .39).Conclusions: Among women with private health insurance and access to care, the incidence of a positive screen for postpartum depression is approximately 7%. The use of an SSRI did not eliminate this risk. All women should be screened for postpartum depression.

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Background: Regulation of medical applications (apps) has not been rigorous. Concern for inaccurate medical apps with potential health consequences has increased. Objective: To identify mobile apps for fetal heart rate monitoring (FHM) and to evaluate their accuracy through a case report. Methods: A list of FHM apps was found in the Apple iTunes stores using a comprehensive list of search terms. After excluding apps irrelevant to this study, all unique apps were then downloaded and evaluated for necessary purchase of an accessory item, presence of disclaimer regarding medical advice, and accuracy of medical content. Those apps that did not require additional purchases were tested for ability to detect heart rates. Results: A total of 30 unique FHM apps were generated. Of these apps, 1 app required an in-app purchase to use and 7 apps required purchase of an accessory device and thus were not further evaluated. Of the 22 remaining apps, all (100%) of the applications were unable to detect the fetal heart rate. Further data collection revealed additional issues, including duplicates, lack of medical disclaimers regarding medical use of the app, and false information in the app content. Conclusion: Identification of FHM apps that do not require additional purchases revealed that all apps were inaccurate. In addition, some apps did not provide a disclaimer and/or contained false information. Healthcare providers should understand the problems with these FHM apps and educate their patients on the inaccuracies and potential dangers of the use of these applications.

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Leakage of colonised oropharyngeal secretions across the tracheal tube cuff may cause iatrogenic pulmonary infection. We studied a novel 'add-on' cuff, which can be inserted over an existing tracheal tube and advanced into the subglottic region. The physical properties of the novel silicone cuff (BronchoGuard, Ciel Medical, USA) were evaluated in comparison with the Hi-Lo® tracheal tube. In a bench study, we identified saline inflation volumes required to transmit pressures between 15 and 30 cmH2 O against artificial tracheas of 18, 20 and 22 mm internal diameter. We computed cuff compliance, and minimal inflation volume to achieve air sealing during mechanical ventilation. Finally, we compared the leakage flow rate of artificial saliva across the novel cuff. On average, the mean (SD) inflation volumes necessary to transmit tracheal pressures of 15, 20, 25 and 30 cmH2 O were 4.1 (2.2), 4.4 (2.3), 4.6 (2.4) and 4.8 (2.4) ml for the novel cuff and 7.7 (2.5), 8.0 (2.6), 8.4 (2.6) and 8.7 (2.7) ml for the Hi-Lo tube, respectively (p < 0.001). The minimal inflation volumes to achieve air sealing were 3.8 (0.9) and 10.5 (2.1) ml (p < 0.001), which resulted in transmitted tracheal pressures of 8.3 (9.8) and 27.6 (34.8) cmH2 O (p < 0.001). Compliance was 0.026 (0.004) and 0.616 (0.324) ml.cmH2 0-1 , respectively (p < 0.001). Although massive leak was found when the novel cuff transmitted pressures ≤ 20 cmH2 O against the trachea, leakage was avoided with pressures ≥ 25 cmH2 O, owing to optimal contact between the cuff and the tracheal wall. In contrast, the standard cuff consistently leaked irrespective of the pressure. We conclude that the novel cuff has advantageous properties that warrant clinical corroboration.

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OBJECTIVE: To compare twin pregnancy outcomes between white and nonwhite women with similar access to health care. METHODS: Retrospective cohort study of all twin pregnancies delivered by a single maternal-fetal medicine practice from 2005-2016. All patients had private health insurance and equal access to physician care. Outcomes were compared between white and nonwhite women using logistic regression to adjust for differences at baseline. RESULTS: Of the 858 women included, 730 (85.1%) were white and 128 (14.9%) were nonwhite. Univariate analysis demonstrated that nonwhite women had higher rates of preterm birth <32 weeks (12.5 versus 6.7%, p = .022), cesarean delivery (78.1% versus 61.4% of all women, p < .001 and 43.5% versus 16.1% of women who attempted labor, p < .001), preeclampsia (22.4% versus 14.5%, p = .029) and gestational diabetes (23.2% versus 7.3%, p < .001). On adjusted analysis, nonwhite race remained significantly associated with cesarean delivery in women who attempted labor (aOR 2.27, 95% CI: 1.09, 4.71) and gestational diabetes (aOR 2.61, 95% CI: 1.53, 4.45). CONCLUSIONS: Nonwhite women with twin pregnancies have an increased risk of adverse outcomes that cannot be explained by access to care. Although improving access to care is an important goal for health care systems, our data suggest that this alone will not eliminate all disparities in health care outcomes between women of different races.

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We present new experimental data of the low-temperature metastable region of liquid water derived from high-density synthetic fluid inclusions (996-916 kg m-3) in quartz. Microthermometric measurements include: (i) prograde (upon heating) and retrograde (upon cooling) liquid-vapour homogenisation. We used single ultrashort laser pulses to stimulate vapour bubble nucleation in initially monophase liquid inclusions. Water densities were calculated based on prograde homogenisation temperatures using the IAPWS-95 formulation. We found retrograde liquid-vapour homogenisation temperatures in excellent agreement with IAPWS-95. (ii) Retrograde ice nucleation. Raman spectroscopy was used to determine the nucleation of ice in the absence of the vapour bubble. Our ice nucleation data in the doubly metastable region are inconsistent with the low-temperature trend of the spinodal predicted by IAPWS-95, as liquid water with a density of 921 kg m-3 remains in a homogeneous state during cooling down to a temperature of -30.5 °C, where it is transformed into ice whose density corresponds to zero pressure. (iii) Ice melting. Ice melting temperatures of up to 6.8 °C were measured in the absence of the vapour bubble, i.e. in the negative pressure region. (iv) Spontaneous retrograde and, for the first time, prograde vapour bubble nucleation. Prograde bubble nucleation occurred upon heating at temperatures above ice melting. The occurrence of prograde and retrograde vapour bubble nucleation in the same inclusions indicates a maximum of the bubble nucleation curve in the ϱ-T plane at around 40 °C. The new experimental data represent valuable benchmarks to evaluate and further improve theoretical models describing the p-V-T properties of metastable water in the low-temperature region.

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OBJECTIVE: To compare the efficacy of three slow expiratory airway clearance techniques (ACTs). DESIGN: Randomised crossover trial. SETTING: Tertiary hospital. PARTICIPANTS: Thirty-one outpatients with bronchiectasis and chronic sputum expectoration. INTERVENTIONS: Autogenic drainage (AD), slow expiration with glottis opened in lateral posture (ELTGOL), and temporary positive expiratory pressure (TPEP). MAIN OUTCOMES: Sputum expectoration during each session (primary endpoint) and in the 24-hour period after each session. Leicester Cough Questionnaire (LCQ) score and spirometry results were recorded at the beginning and after each week of treatment. Data were summarised as median difference [95% confidence interval (CI)]. RESULTS: Median (interquartile range) daily expectoration at baseline was 21.1 (15.3 to 35.6)g. During physiotherapy sessions, AD and ELTGOL expectorated more sputum than TPEP [AD vs TPEP 3.1g (95% CI 1.5 to 4.8); ELTGOL vs TPEP 3.6g (95% CI 2.8 to 7.1)], while overall expectoration in the 24-hour period after each session was similar for all techniques (P=0.8). Sputum clearance at 24hours post-intervention was lower than baseline assessment for all techniques [AD vs baseline -10.0g (95% CI -15.0 to -6.8); ELTGOL vs baseline -9.2g (95% CI -14.2 to -7.9); TPEP vs baseline -6.0g (95% CI -12.0 to -6.1)]. The LCQ score increased with all techniques (AD 0.5, 95% CI 0.1 to 0.5; ELTGOL 0.9, 95% CI 0.5 to 2.1; TPEP 0.4, 95% CI 0.1 to 1.2), being similar for all ACTs (P=0.6). No changes in lung function were observed. CONCLUSIONS: Slow expiratory ACTs enhance mucus clearance during treatment sessions, and reduce expectoration for the rest of the day in patients with bronchiectasis. CLINICAL TRIAL REGISTRATION NUMBER: NCT01854788.

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