Fetal oxygenation, assessment of fetal well-being, and obstetric management of the pregnant patient with asthma

Asthma in Pregnancy

Asthma is a common chronic respiratory condition that affects approximately 10% of adult women in the United States. Pregnancy can present unique challenges for women with asthma, as changes in the body can alter the severity and management of asthma-related respiratory symptoms. In this article, we review the current understanding of asthma during pregnancy, including the direct effects of the disease state on the pregnant woman and fetus, risk factors for poor control of disease, as well as current treatment recommendations.

Extracorporeal Membrane Oxygenation During Pregnancy

In the last 2 decades, the use of venovenous (VV) and venoarterial (VA) extracorporeal membrane oxygenation (ECMO) during pregnancy and the postpartum period has increased, mirroring the increased utilization in nonpregnant individuals worldwide. VV ECMO provides respiratory support for patients with acute respiratory distress syndrome (ARDS) who fail conventional mechanical ventilation. With the COVID-19 pandemic, the use of VV ECMO has increased dramatically and data during pregnancy and the postpartum period are overall reassuring. In contrast, VA ECMO provides both respiratory and cardiovascular support. Data on the use of VA ECMO during pregnancy are extremely limited.

Status Asthmaticus Gravidus: Emergency and Critical Care Management of Acute Severe Asthma During Pregnancy

One-third of women with asthma have deterioration of their asthma during pregnancy, and one-fourth of pregnant women with asthma will experience severe exacerbations necessitating emergency department (ED) visits or hospitalizations. Early recognition of acute severe asthma, including life-threatening status asthmaticus, and aggressive medical interventions with β2-agonists, anticholinergic agents, and systemic corticosteroids are necessary to treat maternal airway bronchoconstriction, support maternal and fetal oxygenation, and avoid adverse fetal outcomes. This review describes management of acute severe asthma in pregnancy, including status asthmaticus, in the ED and intensive care unit.

Extracorporeal Membrane Oxygenation for Pregnant and Postpartum Patients

Extracorporeal membrane oxygenation (ECMO) has seen increasing use for critically ill pregnant and postpartum patients over the past decade. Growing experience continues to demonstrate the feasibility of ECMO in obstetric patients and attest to its favorable outcomes. However, the interaction of pregnancy physiology with ECMO life support requires careful planning and adaptation for success. Additionally, the maintenance of fetal oxygenation and perfusion is essential for safely continuing pregnancy during ECMO support. This review summarizes the considerations for use of ECMO in obstetric patients and how to address these concerns.

Maternal anaphylactic shock in pregnancy: A case report

RATIONALE

Anaphylaxis is a very rare event in pregnancy, triggering maternal hypotension leading to intrapartum hypoxic-ischemic encephalopathy in infant. Furthermore, cesarean sections are performed at a high rate in anaphylactic pregnant women.

PATIENT CONCERNS

A 34-year-old pregnant woman presented with maternal anaphylaxis following prophylactic antibiotic injection for cesarean section. Within a few minutes after initiation of intradermal skin test with cefotetan, the pregnant woman developed generalized itchy rash, chest tightness, and dyspnea.

DIAGNOSES

Several minutes after the injection of antibiotics, a diffuse urticarial rash was detected over her face and trunk followed by complaints of chest tightness and dyspnea. She was diagnosed with hypotension and hypoxia. Further, fetal heart tones showed bradycardia. A presumptive diagnosis of anaphylactic reaction induced by cefotetan was made for surgical prophylaxis.

INTERVENTIONS

The patient was managed for anaphylaxis, via administration of epinephrine, glucocorticoid, and antihistamine. Emergency cesarean section performed under general anesthesia resulted in a favorable perinatal outcome for the fetus.

OUTCOMES

Maternal and fetal outcomes were good after prompt treatment for anaphylaxis and emergency cesarean section.

LESSONS

This is the first reported case of anaphylaxis following cefotetan administration in pregnancy. Cefotetan, a second-generation cephalosporin, is a commonly prescribed antibiotic used to treat a wide range of bacterial infections. The case demonstrated life-threatening anaphylactic reaction during pregnancy. Even a skin test using antibiotics alone triggered anaphylaxis.

Effect of maternal oxygen inhalation on foetal free radical activity: a prospective, randomized trial

BACKGROUND

Maternal inhalation of 35-40% oxygen concentration has no significant effect on foetal partial pressure of oxygen, and 60-100% produced maternal and foetal hyperoxia with increased free radical activity. The benefit of 50% maternal oxygen inhalation on foetal oxygenation, oxidant stress and total antioxidant status (TAS) during Caesarean section (CS) has not been simultaneously evaluated.

METHODS

In this prospective, randomized, controlled trial 120 ASA physical status I-II, term pregnant women were recruited to elective CS (n = 60) and emergency CS (n = 60) and received either 50% oxygen or air inhalation following subarachnoid block (SAB). Patients and investigators were blinded to the inhaled oxygen concentration. The primary outcome of the study was foetal umbilical artery (UA) malondialdehyde (MDA) at birth.

RESULTS

In both elective and emergency CS, there was no difference in foetal oxidative stress and TAS in spite of increase in maternal PaO2. In elective CS, maternal MDA was higher at delivery in mothers breathing 50% oxygen as compared to their own baseline values (P = 0.04). In emergency CS, maternal TAS at 10 min was lower in mothers inhaling 50% oxygen as compared to air (P = 0.01). The average duration of maternal oxygen supplementation was ~10.3 min in elective and ~7.4 min in emergency CS. Neonatal outcome, episodes of maternal hypotension and oxygen desaturation were similar in both the groups.

CONCLUSION

Brief duration of 50% oxygen maternal inhalation during elective or emergency CS did not significantly affect foetal MDA and TAS under SAB.

Case Report of S1Q3T3 Electrocardiographic Abnormality in a Pregnant Asthmatic Patient During Acute Bronchospasm

Patient: Female, 33

Final Diagnosis: S1Q3T3 electrocardiographic abnormality in a pregnant asthmatic during acute bronchospasm

Symptoms: Cough • shortness of breath

Medication: —

Clinical Procedure: EKG

Specialty: Pulmonology

Low risk of adverse obstetrical and perinatal outcome in pregnancies complicated by asthma: A case control study

BACKGROUND

Asthma in pregnancy have been associated with an increased risk of pregnancy complications. Our aim was to estimate incidence and describe risk factors for adverse obstetrical and perinatal outcomes in pregnant women with asthma.

METHODS

Women enrolled in the Management of Asthma during Pregnancy (MAP) program were each matched with three controls (i.e. consecutive women giving birth at our obstetrical service). Asthma severity was classified according to treatment step. Data on obstetrical and perinatal outcomes were obtained from medical records. Logistic regression analysis was applied, and findings expressed as odds ratios (OR) unadjusted and adjusted (adj) for BMI, age, parity, smoking, ethnicity and marital status.

RESULTS

Nine-hundred-thirty-nine pregnancies in women with asthma (i.e. cases) were compared to 2.782 controls. Overall, the incidence of complications was low, although women with asthma had a statistically significant higher risk of pre-eclampsia (5% vs. 3%, OR_adj 1.60, 95% CI 1.07-2.38; p = 0.02) and small for gestational age neonates (SGA) (OR_adj 1.30, 95% CI 1.10-1.54; p < 0.01) compared to controls. Compared to mild asthma, more severe asthma was associated with a higher risk of SGA (60% vs 53%, OR_adj. 1.30, 95% CI 1.10-1.54; p < 0.01). Women with asthma exacerbation during pregnancy tended to have a higher risk of severe pre-eclampsia (OR_adj 3.33 95% CI 0.96-11.65, p = 0.06) compared to pregnancies without any exacerbations.

CONCLUSION

The overall risk of adverse obstetrical and perinatal outcomes in pregnancies complicated by asthma is low compared to non-asthmatic women. Our observations suggest that enrollment into an asthma management program has a positive impact on overall pregnancy outcome.

Anaphylaxis during pregnancy

Anaphylaxis during pregnancy, labor, and delivery can be catastrophic for the mother and, especially, the infant. Symptoms and signs can include intense vulvar and vaginal itching, low back pain, uterine cramps, fetal distress, and preterm labor. During the first 3 trimesters, etiologies are similar to those in nonpregnant women. During labor and delivery, common etiologies are β-lactam antibiotics, natural rubber latex, and other agents used in medical and perioperative settings. Important caveats in management include injecting epinephrine (adrenaline) promptly, providing high-flow supplemental oxygen, positioning the mother on her left side to improve venous return to the heart, maintaining a minimum maternal systolic blood pressure of 90 mm Hg to ensure adequate placental perfusion, and continuous electronic monitoring. Cardiopulmonary resuscitation and emergency cesarean delivery should be performed when indicated. In all women of child-bearing age, allergy/immunology specialists can help to prevent anaphylaxis in pregnancy through prepregnancy risk assessment and risk reduction strategies, such as confirming the etiology of systemic allergic reactions, providing written instructions for allergen avoidance, and initiating relevant immune modulation. In pregnant women the benefits versus risks of skin tests, challenge tests, desensitization, and initiation of immunotherapy with allergens should be carefully weighed; if possible, these procedures should be deferred until after parturition. Prospective interdisciplinary studies of anaphylaxis during pregnancy are needed.

Computerized cardiotocography in pregnancies complicated by maternal asthma

OBJECTIVE

The aim of the present study was to investigate the FHR parameters in term pregnancies complicated by asthma.

STUDY DESIGN

prospective cross-sectional study performed between July 2008 and November 2009. Twenty-one singleton pregnancy between 36 and 40 weeks gestation with diagnosis of maternal asthma and no current use of oral corticosteroids were compared with 30 pregnancies without morbidities at the same gestational age. The computerized cardiotocography (System 8002, Sonicaid) was performed and 30 min analysis was studied. Statistical analysis included Student's t-test or Mann-Whitney U test for comparisons between groups. Categorical data were compared using the χ(2)-test or Fisher's exact test.

RESULTS

There were no significant differences in FHR parameters analyzed by computerized cardiotocography: basal FHR (p = 0.80), number of accelerations >10 bpm (p = 0.08) or > 15 bpm (p = 0.20), duration of high episodes (p = 0.70), duration of low episodes (p = 0.46) and STV (p = 0.66). Asthmatic mothers presented mean number of fetal movement per hour significantly lower than control group (34.6 ± 28.2 vs. 60.6 ± 43.1, p = 0.02).

CONCLUSION

Computerized cardiotocography demonstrates no association between the abnormal parameters of FHR and maternal asthma in term pregnancies. Maternal asthma was associated with less fetal movements per hour, suggesting further studies on the counting of fetal movements in pregnant women with asthma.

Maternal allergy acts synergistically with cigarette smoke exposure during pregnancy to induce hepatic fibrosis in adult male offspring

Maternal environmental exposures during pregnancy are known to affect disease onset in adult offspring. For example, maternal asthma exacerbations during pregnancy can worsen adult asthma in the offspring. Cigarette smoking during pregnancy is associated with future onset of cardiovascular disease, obesity and diabetes. However, little is known about the effect of maternal environmental exposures on offspring susceptibility to liver disease. This pilot study examined the long-term effect of maternal allergen challenge and/or cigarette smoking during pregnancy on hepatic inflammation and fibrosis in adult mouse offspring. Ovalbumin (OVA) or phosphate-buffered saline (PBS)-sensitized/challenged CD-1 dams were exposed to mainstream cigarette smoke (MCS) or filtered air from gestational day 4 until parturition. Eight weeks postnatally, offspring were sacrificed for comparison of hepatic histology and mRNA expression. Adult male offspring of OVA-sensitized/challenged dams exposed to MCS (OSM) displayed significantly increased liver fibrosis (9.2% collagen content vs. <4% for all other treatment groups). These mice also had 1.8-fold greater collagen 1A1 mRNA levels. From the results here, we concluded that maternal allergen challenge in combination with cigarette smoke exposure during pregnancy may be an important risk factor for liver disease in adult male offspring.

Maternal and neonatal outcomes of pregnancies complicated by asthma in an Australian population

OBJECTIVE

To determine if there are sex differences in risk and incidence of stillbirth, preterm delivery and small-for-gestational age (SGA) in pregnancies complicated by maternal asthma relative to a non-asthmatic population.

STUDY DESIGN

Univariant and multiple regression analysis of the incidence of preterm delivery, SGA and stillbirth in singleton pregnancies complicated by asthma in Newcastle, NSW, Australia, from 1995 to 1999.

RESULTS

Asthma complicated 12% of all singleton pregnancies. The incidence of preterm delivery was not significantly different between asthmatic (13%) and non-asthmatic (11%) pregnancies. Male fetuses (53%) were more likely to deliver preterm than female fetuses (47%) in both asthmatic and non-asthmatic populations. There were significantly more male neonates of pregnancies complicated by asthma that were SGA at term relative to those of the non-asthmatic population. There were significantly more preterm female neonates that were SGA in pregnancies complicated by asthma relative to those of the non-asthmatic population. Male fetuses were more likely to be associated with a stillbirth in pregnancies complicated by asthma than female fetuses.

CONCLUSION

The presence of maternal asthma during pregnancy increases the risk of stillbirth for the male fetus and is associated with changes in fetal growth, but does not increase the incidence of a preterm delivery.

Effect of maternal moderate to severe asthma on perinatal outcomes

BACKGROUND/OBJECTIVES

It has been reported that adverse fetal outcomes are more prevalent in pregnant women with asthma than they are in women without asthma. In our study, we investigated the effect that the severity of asthma during pregnancy has on the risk of a small for gestational age (SGA) infant, low birth weight (LBW), and preterm birth.

METHODS

A population-based cohort of 13,007 pregnancies from asthmatic women was reconstructed through the linking of three of Quebec's (Canada) administrative databases covering the period between 1990 and 2002. A two-stage sampling cohort design was used to collect additional information on the selected women's life-style habits via a mailed questionnaire. Asthma severity during pregnancy was measured with a validated database index. A logistic regression model was used to obtain the adjusted odds ratios of SGA, LBW and preterm birth as a function of the level of asthma severity.

RESULTS

The proportions of women with mild, moderate and severe asthma were 82.5%, 12.5% and 5.0%, respectively. We sent 3,168 questionnaires to selected women, with a 40.2% (n=1274) response rate. Final estimates showed that the risk of SGA was significantly higher among severe (OR:1.48, 95%CI: 1.15-1.91) and moderate asthmatic women (OR: 1.30, 95%CI:1.10-1.55) than mild asthmatic women. No significant associations were found between asthma severity, preterm birth and LBW.

CONCLUSIONS

Mothers with severe and moderate asthma during pregnancy have a higher risk of SGA babies than those with mild asthma.

High doses of inhaled corticosteroids during the first trimester of pregnancy and congenital malformations

BACKGROUND

Although reassuring data exist on the use of low-to-moderate doses of inhaled corticosteroids (ICSs) during pregnancy, there are inadequate data for women receiving high doses.

OBJECTIVE

To investigate the association between doses of ICS during the first trimester of pregnancy and the risk of congenital malformations among women with asthma.

METHODS

We conducted a cohort study of 13,280 pregnancies of women with asthma (1990-2002) by linking 3 administrative databases from Quebec (Canada). By using generalized estimation equation models, we compared women taking >0 to 1000 microg/d ICS (beclomethasone dipropionate-chlorofluorocarbone equivalent) with women taking >1000 microg/d and those not taking ICSs. The main outcome measures were all and major congenital malformations.

RESULTS

We identified 1257 infants with a congenital malformation (9.5%) and 782 infants with a major malformation (5.9%). We found that women who used >1000 microg/d ICS (n = 154) were significantly more likely (63%) to have a baby with a malformation than the 4392 women who used >0 to 1000 microg/d (adjusted risk ratio, 1.63; 95% CI, 1.02-2.60). On the other hand, women who used >0 to 1000 microg/d were not found to be more at risk than women who did not use ICSs during the first trimester (n = 8734). Nonsignificant trends of similar magnitude were found for major malformations.

CONCLUSIONS

Our study adds evidence on the safety of low-to-moderate doses of ICS taken during the first trimester but raises concerns about high doses. However, we cannot rule out the possibility of residual confounding by severity in this association.

Asthma exacerbations during the first trimester of pregnancy and the risk of congenital malformations among asthmatic women

BACKGROUND

Uncontrolled maternal asthma during pregnancy has been hypothesized as a cause of congenital malformation, but literature is scare on this topic.

OBJECTIVE

The aim of this study was to investigate whether asthmatic women who had an exacerbation during the first trimester of pregnancy were more at risk of having a baby with a congenital malformation.

METHODS

From the linkage of 3 Canadian administrative databases, we reconstructed a cohort of 4344 pregnancies of asthmatic women. Asthma exacerbations were assessed during the first trimester of pregnancy and were defined as a filled prescription for oral corticosteroids, an emergency department visit, or a hospitalization for asthma. Congenital malformations were assessed at birth and during the first year of life of the newborn by using diagnoses recorded in the databases. Generalized estimating equation models were used to estimate adjusted odds ratios of congenital malformations in association with asthma exacerbations.

RESULTS

In the cohort we identified 398 (9.2%) babies with at least 1 malformation and 261 (6.0%) with a major malformation. The crude prevalences of malformations were 12.8% and 8.9%, respectively, for women who had and those who did not have an exacerbation. The adjusted odds ratio for all malformations was 1.48 (95% CI, 1.04-2.09) when comparing women who had and those who did not have an exacerbation. The corresponding figures were 1.32 (95% CI, 0.86-2.04) for major malformations.

CONCLUSION

Asthma exacerbations during the first trimester of pregnancy were found to significantly increase the risk of a congenital malformation.

Maternal asthma and placental morphometry: effects of severity, treatment and fetal sex

Asthma is the most common respiratory disease to complicate pregnancy. Although adverse effects on the fetus have been documented, there is a paucity of information regarding the effects of asthma, and its treatment, on placental morphology. The aim of this study was to test for volumetric differences in placental composition between non-asthmatic pregnancies and those associated with maternal asthma grouped according to asthma severity and glucocorticoid (GC) treatment. Each placenta was weighed and random samples of tissue were fixed in formalin-saline, embedded in wax and analysed by design-based stereology. Volume densities of parenchymal compartments (peripheral villi and maternal intervillous space) and residual non-parenchyma were estimated by test point counting and converted to absolute volumes by taking into account placental size. Relative and absolute lengths of villi and capillaries were also estimated and used to derive secondary quantities related to villous capillarization and maturation. Between-group comparisons were drawn by two-way analysis of variance with group and fetal sex as the principal factors. Compared to non-asthmatic controls, asthmatics had reduced absolute volumes of fetal capillaries which was most marked in those with moderate/severe asthma and those using low and high doses of inhaled GCs. Changes in the total length and mean cross-sectional area of capillaries and peripheral villi were also observed. Lengths were greater in mild asthmatics and lowest in those with high GC usage. Calibre areas were lower in mild asthmatics and villous calibres in the high GC group were greater than those in asthmatics not taking GCs. Those making greatest use of inhaled GCs also had villi which were hypovascularized in terms of capillary:villus length ratios. The findings suggest that the morphometric differences in fetoplacental vascularity are likely to be due to the effects of asthma and use of inhaled GCs rather than the effects of maternal or fetal hypoxic stress.

Use of inhaled corticosteroids during the first trimester of pregnancy and the risk of congenital malformations among women with asthma

AIM

To investigate whether the maternal use of different doses of inhaled corticosteroids (ICSs) during the first trimester of pregnancy for the treatment of asthma increases the risk of congenital malformations in the offspring.

METHODS

From the linkage of three administrative Canadian databases, a cohort of 4561 pregnancies from women with asthma who delivered between 1990 and 2000 was reconstructed. A two-stage sampling cohort design was used to acquire additional data from the woman's medical chart. Cases of congenital malformation were identified from the medical services database or the hospital database. Using refill patterns of medications, the average daily dose of ICSs used during the first trimester was calculated and categorised as follows: 0, 1-500, 500-1000 and >1000 microg/day in beclomethasone-chlorofluorocarbon equivalent. A Generalized Estimation Equation model was used to estimate the adjusted odds ratio of congenital malformation as a function of ICS daily dose. All analyses were performed for all malformations and major malformations separately.

RESULTS

Within the cohort 418 babies were identified with a congenital malformation (9.2%), 278 of which had a major malformation. About 40% of women used ICSs during the first trimester, but only 5.3% of women used >500 microg/day. The adjusted odds ratio (95% CI) for all malformations associated with the use of ICSs during the first trimester was: 0.77 (0.53 to 1.13) for 1-500, 0.41 (0.19 to 0.92) for 501-1000 and 1.00 (0.42 to 2.36) for >1000 microg/day. The corresponding figures for major malformations were 0.90 (0.64 to 1.24), 0.56 (0.22 to 1.43) and 1.67 (0.56 to 5.03).

CONCLUSION

This study adds evidence to the safety of ICSs for the treatment of asthma during pregnancy, with regard to the likelihood of congenital malformation.

Caring for pregnant and postnatal women in intensive care: what do we know?

Critically ill pregnant and postnatal women admitted to intensive care units (ICUs) require highly specialised care, components of which many critical care nurses are unfamiliar with. There are no specialist critical care obstetric centres in Australia, with critically ill obstetric patients admitted to general ICUs. There are no published guidelines and little research that assist critical care nurses to care for such women. Furthermore, the admission of pregnant or postnatal women to ICUs is likely to increase with emerging childbearing patterns in Australia. It is therefore timely to review what we know about caring for critically ill pregnant and postnatal women. This paper analyses the literature on intensive care utilisation by obstetric patients and provides an overview regarding which pregnant and postpartum women require intensive care. The key areas of providing mechanical ventilation to pregnant women and assessment of fetal wellbeing are explored in detail. The most frequent conditions and their treatment, preeclampsia and obstetric haemorrhage, are also reviewed. The establishment of lactation is also considered as the critical carenurse is commonly involved in supporting the woman's endeavour to breastfeed.

Acute asthma during pregnancy

In addition to preventing maternal and fetal hypoxia, the goals of treating acute asthma exacerbation during pregnancy mirror those in the nongravid patient: rapid reversal of airflow obstruction with aerosolized bronchodilators,reduction of likelihood of recurrence by the addition of corticosteroids, and ongoing assessment of mother and fetus. Disposition decisions are multifaceted and must take into account the health and well-being of the pregnant patient and that of her fetus. Discharge planning includes prescription of scheduled 3-2 agonist treatments until symptoms resolve, intensification of daily treatment as needed, prescriptions for systemic and ICSs, as well provision of patient education, a personalized action plan, and close follow-up.

Acute asthma in pregnancy

OBJECTIVES

To provide an overview on the interrelationship between asthma and pregnancy, focusing on management of pregnant women presenting with an acute severe exacerbation.

DESIGN

A review of the current English-language published clinical trials was performed based on MEDLINE search using the Medical Subject Headings pregnancy and asthma. Current reviews on the topic and practice guidelines were also reviewed.

RESULTS

Asthma is the most common medical condition to complicate pregnancy, and episodes of acute asthma requiring emergency department visits or hospitalization have been reported in 9-11% of pregnant women managed by asthma specialists. Pregnancy can affect the course of asthma, and the risk of asthma exacerbations requiring intervention in pregnant women is higher than in nonpregnant women. Similarly, asthma can affect pregnancy outcomes. Maternal inflammatory pathways may contribute to the poor pregnancy outcomes, especially in women with uncontrolled asthma. Although data on the effects of maternal asthma on pregnancy have been conflicting, mainly because many published studies have not corrected for asthma severity, it has generally been observed that poorly managed asthma during pregnancy is associated with a higher risk of preterm delivery, low birth weight, and complications such as preeclampsia. Optimal therapy of asthma has been shown to contribute to improved maternal and fetal outcomes.

CONCLUSIONS

Asthma can complicate the course of pregnancy, and pregnancy can worsen asthma control in some women. Optimal management of asthma during pregnancy is key in ensuring the safety of the mother and the fetus.

Acute pulmonary edema in pregnancy

Pulmonary edema is a secondary disease process characterized by an excess accumulation of fluid in the pulmonary interstitial and alveolar spaces, preventing adequate diffusion of both oxygen and carbon dioxide. The excess fluid accumulation interferes with maternal oxygenation and, if not identified and corrected, can lead to maternal and fetal hypoxemia. The purpose of this article is to review principles of oxygen transport and the pathophysiology, diagnosis, management, and nursing implications of acute pulmonary edema in pregnancy.

Acute asthma in pregnancy

Asthma is one of the most common medical conditions that can complicate pregnancy. Although most pregnant women with asthma have controlled disease, some women may experience exacerbation of their disease, necessitating immediate intervention. This article discusses the interrelations between asthma and pregnancy and presents an overview on the management of pregnant women presenting to the hospital with acute severe asthma. Treating physicians must overcome the common belief that pregnant women should not take any medications during pregnancy, and they should keep asthma in pregnant women under control to minimize the risk for maternal and fetal hypoxia.

[Analysis of 83 bronchospasm episodes seen at urgent care during one spring night]

BACKGROUND

The new treatments for the bronchial inflammation in asthma, have contributed to decrease the mortality rate. However, there is still a group of population with no diagnosis fo asthma, who requires urgent medical attention in situations such as air pollution or risen pollen levels. On 2nd June 2000, 83 subjects with an acute crisis of asthma, came to the Emergency Room in our Hospital in just 6 hours, coinciding with the highest annual pollen measurement and a strong storm.

METHODS AND RESULTS

Personal data from those 83 patients, medical behaviour at the Casualty and post-attention recommendations were considered for analysis. 21 % never had previous diagnosis of asthma and 93 % followed no regular medical control. 61.45 % did no treatment. A chest radiography was taken in 53.76 % of the patients. Salbutamol was administrated in most of them (92.18 %) and parentally administration of steroids in 23.47 %. 21 % were referred to an specialist.

CONCLUSIONS

A significant rate of asthmatics is under-diagnosed, under-controlled and under-treated. Public Health authorities should consider the creation of new Allergy Units, a fluid communication between general practitioners and specialists, and the monitorization of pollen recounts with special plans of emergency situations to contribute to solve this problem.

Alterations of placental vascular function in asthmatic pregnancies

Asthma during pregnancy is associated with low-birthweight neonates at term but the mechanisms that cause this outcome are presently unknown. Changes in placental vascular function resulting from asthma or its treatment could contribute to altered fetal growth. We have prospectively followed women with asthma and a control group of women without asthma during their pregnancies, classified them based on asthma severity and glucocorticoid intake, and monitored fetal development and placental blood flow using Doppler ultrasound at 18 and 30 wk gestation. The placentae from these women were collected after delivery and vascular responses to dilator and constrictor agonists assessed using an in vitro placental perfusion method. At 18 wk gestation, umbilical artery flow velocity waveforms were significantly reduced in the moderate and severe asthmatic groups and in those women using high-dose inhaled glucocorticoid for the treatment of their asthma (ANOVA, p < 0.05). However, at 30 wk gestation there were no significant differences in umbilical artery flow velocity between control and asthmatic women (ANOVA, p > 0.05). Corticotropin-releasing hormone (CRH), a potent vasodilator that acts via the nitric oxide pathway, caused a dose-dependent vasodilatory response in all placentae in vitro. However, CRH-induced dilation was significantly reduced in moderate and severe asthmatics (ANOVA, p < 0.05). Vasoconstrictor responses to potassium chloride and prostaglandin F(2alpha) were reduced in placentae from moderate and severe asthmatic women (ANOVA, p < 0.05). These studies demonstrate significant differences in placental vascular function in pregnancies complicated by asthma, which may relate directly to the asthma or be a consequence of the associated glucocorticoid treatment. These changes in vascular function in asthmatic pregnancies may contribute to the low-birthweight outcome observed in this condition.