Resting Hemodynamics and Response to Exercise Using the 6-Minute Walk Test in Late Pregnancy: An International Prospective Multicentre Study.

BACKGROUND: Cardiac disease is the leading cause of maternal death. Assessment of cardiovascular fitness is important in pregnant women because it is linked to increased risk of cardiac disease but is rarely undertaken or studied. The 6-Minute Walk Test (6MWT) is a safe exercise test but is not used in pregnancy. We determined the 95% reference interval for resting heart rate (HR) and distance walked for the 6MWT, as well as hemodynamic recovery variables, and quantified expectations and actual experiences of exertion and breathlessness with exercise in late pregnancy. METHODS: After institutional research board approval (Australian and New Zealand Clinical Trials Registry Number: 12615000964516), 300 healthy term nulliparous pregnant women performed the 6MWT at 3 tertiary referral obstetric hospitals using a standardized protocol. Each woman underwent two 6MWT with maximum 15-minute recovery period after each test. Hemodynamic variables were measured at rest and after exercise. Participants were asked 4 questions, 2 regarding expectation and 2 regarding actual experience, using the Rating of Perceived Exertion scale and Modified Borg Dyspnea scale. RESULTS: Participant characteristics and resting variables were mean (standard deviation [SD]); age, 31 years (4.2 years); body mass index, 27 kg/m (2.9 kg/m); gestational age, 37 weeks (1.3 weeks); HR, 85 bpm (10.8 bpm) with 95% reference interval 64-106 bpm; systolic blood pressure, 112 mm Hg (10.2 mm Hg); diastolic blood pressure, 72 mm Hg (8.6 mm Hg); oxygen saturation, 98% (0.9%); and respiratory rate, 18 breaths/min (5.7 breaths/min). The mean (SD) average distance walked was 488 m (94.9 m) with a speed of 3.0 mph (0.64 mph) with a 95% reference interval of 302-674 m. The mean (SD) HR increase with exercise was 12 bpm (11.0 bpm) with a median [quartile] recovery time of 5.0 minutes [1-8 minutes]. A lower resting HR was associated with increased distance walked (r = -0.207; 95% confidence interval, -0.313 to -0.096; P < .001). A greater HR change with exercise was associated with increased recovery time from exercise (r = 0.736; 95% confidence interval, 0.697-0.784; P < .001). Sixty-three percent and 83% of participants, respectively, expected to be more exerted and breathless than they actually were with exercise. CONCLUSIONS: The 6MWT is feasible and applicable in term pregnant women. The reference intervals for resting HR and distance walked in the 6MWT have been generated. HR increases by approximately 12 bpm with submaximal exercise, and half of the women recovered within 5 minutes of submaximal exercise. Women expected to be more exerted and breathless than they actually were with exercise.

How do trainee doctors introduce themselves to patients?

OBJECTIVES: To identify how trainee doctors introduce themselves to patients. DESIGN: Survey. SETTING: Chelsea and Westminster Hospital, London. PARTICIPANTS: One hundred trainee doctors, of mixed grades and specialties. MAIN OUTCOME MEASURES: Introducing oneself by name, using their professional title 'Dr', use of the term 'trainee'. RESULTS: All 100 participants introduced themselves by name to patients, with 63% using only their first name, 18% using only their last name and 18% using a combination of both. 67% mentioned their specialty and 18% mentioned their training grade. 85% identified themselves as a doctor, but only 22% used their professional title (Dr), and only 6% introduced themselves by name, grade, specialty and title. 80% varied the way they introduced themselves to patients, depending on several factors including the clinical situation and patients' characteristics/features. 56% said that they had changed the way they introduced themselves over time, and 42% deliberately avoided the term 'trainee' during introductions. There was no association between trainees' age, gender or specialty and their comfort in describing themselves as 'trainees', but the more junior trainees were more comfortable using this term than the senior grades (p<0.0001). Overall, 76% disliked the term 'trainee', for various reasons. CONCLUSION: All doctors in this study introduced themselves by name but the majority did not specify their training grade or trainee status, predominantly because they believed it could trigger anxiety around their competence or undermine confidence in their abilities.

Anaesthesia for the obstetric patient with (non-obstetric) systemic disease.

The number of women with serious (non-obstetric) systemic diseases achieving pregnancy and requiring obstetric anaesthetic management is increasing. The conditions that are most likely to cause maternal morbidity and mortality are cardiac disease, respiratory disease, neuromuscular disease, haematological disease, connective and metabolic diseases and psychiatric conditions including substance abuse. This article discusses the anaesthetic management of the pregnant mother with such serious systemic diseases.

Effect of pregnancy on clinical status and ventricular function in women with heart disease.

BACKGROUND: Pregnant women with heart disease (HD) are at an increased risk for maternal and neonatal adverse events. However, the effect of pregnancy on clinical status and ventricular function in women with HD has not been examined in a controlled study. METHODS AND RESULTS: Ninety-three women with HD were studied longitudinally. Of these, fifty-three underwent clinical and echocardiographic evaluation before and 1.5+/-1.1 years after pregnancy (pregnancy group), whereas forty served as controls matched for age (28.6+/-4.6 versus 28.5+/-6.6, p=0.88), diagnosis, and length of follow-up (2.9+/-1.4 versus 2.6+/-1.1, p=0.23). NYHA functional class remained unchanged in both groups during follow-up. End diastolic and end systolic dimensions and shortening fraction of the morphologic left ventricle also remained unchanged. Furthermore, systemic and subpulmonary ventricular function remained unchanged in the pregnancy and control groups on semiquantitative analysis. Pregnancy, however, was associated with a persisting increase in subpulmonary ventricular size in patients with tetralogy of Fallot (ToF) which was not present in tetralogy controls. Furthermore, diagnosis of ToF was the only predictor of an increase in subpulmonary ventricular size after pregnancy on univariate logistic regression analysis (OR 8.8[95% CI 1.9-41.1], p=0.006). CONCLUSIONS: In this longitudinal controlled study amongst women with HD no deleterious midterm effects of pregnancy on clinical status and right and left ventricular function were found. However, pregnancy was associated with a persisting increase in subpulmonary ventricular size, attributable to patients with repaired ToF. This may have prognostic implications and merits further investigation.

Contesting the science/ethics distinction in the review of clinical research.

Recent policy in relation to clinical research proposals in the UK has distinguished between two types of review: scientific and ethical. This distinction has been formally enshrined in the recent changes to research ethics committee (REC) structure and operating procedures, introduced as the UK response to the EU Directive on clinical trials. Recent reviews and recommendations have confirmed the place of the distinction and the separate review processes. However, serious reservations can be mounted about the science/ethics distinction and the policy of separate review that has been built upon it. We argue here that, first, the science/ethics distinction is incoherent, and, second, that RECs should not only be permitted to consider a study's science, but that they have an obligation do so.

Controversies in pregnancy and congenital heart disease.

As increasing numbers of children with congenital heart disorders reach adulthood, the family physician, cardiologist, and obstetrician will increasingly be called upon to give advice regarding the safety of pregnancy. This need has been further highlighted by the recognition that maternal mortality associated with cardiac disease is rising. Unfortunately, this field of practice remains relatively "evidence-sparse" with many management decisions being guided by anecdote and "best guess" common sense. Not surprisingly, this results in many fundamental controversies over the optimal care these patients should receive. This article highlights, through the use of case histories, some of these contentious areas, reflecting the different manifestations of congenital maternal cardiac disease and highlighting the limitations of our knowledge.

Maternal temperature monitoring during labor: concordance and variability among monitoring sites.

OBJECTIVE: Elevated maternal temperature in labor is associated with adverse immediate and long-term neonatal outcomes. Conventional methods of temperature measurement may not reflect the intrauterine temperature, which constitutes the fetal environment. The purpose of this study was to ascertain the most reliable noninvasive method of temperature monitoring in labor that would best reflect changes in intrauterine temperature. METHODS: Women in labor receiving epidural analgesia had temperature readings taken every 10 seconds from the uterine cavity, ear canal, and skin surface of the leg and abdomen and hourly from the mouth. RESULTS: Eighteen patients were studied for a mean of 228 minutes (range 56-464 minutes). The best indicator of intrauterine temperature was oral temperature, with a mean intraclass correlation coefficient of 0.6 (95% confidence interval 0.42, 0.77). On average, oral temperature underestimated intrauterine temperature by 0.8 degrees C (95% confidence interval 0.7 degrees C, 1 degrees C). Allowing for this, oral temperature greater than 37.2 degrees C detected an intrauterine temperature greater than 38 degrees C with a sensitivity of 81% and a specificity of 96%. The intraclass correlation coefficients of all other sites with intrauterine temperature were poor (0.1 or less). As expected, the temperature at all sites increased as labor progressed. CONCLUSION: Oral temperature, measured carefully, has an acceptable correlation with intrauterine temperature and is recommended for routine detection of maternal pyrexia in labor. Continuous skin and external auditory canal temperature measurements did not correlate well. LEVEL OF EVIDENCE: II-3

P NUTS--a nutritious method of teaching respiratory physiology.

Teaching basic respiratory physiology can be made more interesting and fun by means of a simulation involving active transport (and consumption) of peanuts by the participants. Simple rules simulate the basic features of oxygen transport, hypoxia and hypoxaemia and provide an opportunity to discuss physiological principles at intervals during the simulation.