Rhabdomyolysis After Hyperemesis Gravidarum

Hyperemesis gravidarum and the risk of offspring morbidity: a longitudinal cohort study

PURPOSE

Hyperemesis gravidarum has the potential to affect the long-term health of offspring. We examined whether maternal hyperemesis gravidarum was associated with the risk of hospitalization for childhood morbidity.

METHODS

We conducted a longitudinal cohort study of 1,189,000 children born in Quebec, Canada, between April 2006 and March 2021. The main exposure measure was maternal hyperemesis gravidarum requiring hospitalization in the first or second trimester. The outcome was any pediatric admission between birth and 16 years of age, with follow-up ending in March 2022. We used Cox regression models adjusted for maternal and socioeconomic factors to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between maternal hyperemesis gravidarum and childhood hospitalization.

RESULTS

Among 1,189,000 children, 6904 (0.6%) were exposed to maternal hyperemesis gravidarum. Hospitalization rates at age 16 years were higher for children exposed to hyperemesis gravidarum than unexposed children (47.6 vs 43.9 per 100 children). Relative to no exposure, hyperemesis gravidarum was associated with a 1.21 times greater risk of any hospitalization before 16 years (95% CI 1.17-1.26). Hyperemesis gravidarum was associated with hospitalization for neurologic (HR 1.50, 95% CI 1.32-1.71), developmental (HR 1.51, 95% CI 1.29-1.76), digestive (HR 1.40, 95% CI 1.30-1.52), and allergic disorders (HR 1.39, 95% CI 1.24-1.56). When contrasted with preeclampsia, hyperemesis gravidarum was a stronger risk factor for these outcomes.

CONCLUSIONS

Maternal hyperemesis gravidarum is associated with an increased risk of childhood hospitalization, especially for neurologic, developmental, digestive, and atopic disorders.

WHAT IS KNOWN

• Hyperemesis gravidarum is associated with neurodevelopmental disorders in offspring. • However, the effect of hyperemesis gravidarum on other childhood morbidity is unclear.

WHAT IS NEW

• In this longitudinal cohort study of 1.2 million children, maternal hyperemesis gravidarum was associated with a greater risk of hospitalization before age 16 years. • Exposure to hyperemesis gravidarum was associated with developmental, neurologic, atopic, and digestive morbidity in childhood.

Can the triglyceride-glucose index predict insulin resistance in LGA newborns?

BACKGROUND

The aim of this study is to investigate the TyG index and TG/HDL-C ratio and their relationships with insulin resistance in LGA infants.

METHODS

A prospective controlled study was conducted including 65 LGA and gestational age, gender-matched appropriate for gestational age (AGA) neonates. Serum TG, total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), insulin and glucose levels were measured within two hours after birth, TyG index and HOMA-IR values were calculated.

RESULTS

TyG index and TG/HDL- C ratio were higher in LGA neonates compared to AGA ones (p = 0.03; p = 0.00, respectively). Compared with AGA newborns, LGA newborns had higher levels of insulin and HOMA-IR (p = 0.00; p = 0.00, respectively). TyG index and TG/HDL-C ratio showed moderate correlation with HOMA-IR (r = 0.59 R2 = 0.35 p < 0.001; r = 0.5 R2 = 0.25 p < 0.001, respectively). CONCLUSıON: The results of this study show that LGA newborns have increased levels of TyG index and TG/HDL-C associated with insulin resistance.

From Discomfort to Distress: A Critical Analysis of Hyperemesis Gravidarum in the Emergency Room

Hyperemesis gravidarum (HG) is a severe and debilitating condition characterized by persistent and excessive nausea and vomiting during pregnancy (NVP), often leading to significant maternal and fetal morbidity. This literature review aims to provide a scientifically comprehensive overview of HG within the context of the emergency room (ER) setting. This review aims to enhance understanding and improve the management of HG cases presented to the ER by synthesizing current knowledge and evidence-based practices. This literature review encompasses a systematic analysis of relevant scientific literature, encompassing original research studies, review articles, and clinical guidelines. An extensive search of electronic databases was conducted, covering the period from January 2003 to January 2023. Keywords related to HG, pregnancy-related complications, emergency medicine, and ER management were employed to identify pertinent publications. Through the literature review, we found the incidence of HG-related ER admission to be 0.8%. Although the etiology of HG remains to be unknown, a strong association was found between developing HG in pregnant females and a history of gastrointestinal (GI) disorders, use of cannabis, and pregnancies conceived through artificial reproductive technology (ART). Furthermore, overweight females were more likely to develop HG. Maternal smoking was found to be protective against HG. The symptoms of HG mainly include intractable nausea and vomiting occurring usually between four and nine weeks of gestational age with a significant aversion to food and loss of weight. Diagnosis is done through a strong clinical suspicion, a history of HG in previous pregnancies, and a basic metabolic panel. Treatment includes intravenous (IV) fluids, antiemetic therapy, corticoids, thiamine supplements, and laxatives. In our review, we highlight a few complications that can be seen in HG through a synopsis of unique case reports found during our literature search. In conclusion, through this review, we wish to highlight HG as an obstetrical emergency. We aim to improve understanding, enhance early recognition, and promote evidence-based management strategies for HG in the emergency room. We hope that the findings presented herein will serve as a valuable resource for healthcare professionals, researchers, and policymakers involved in the care of pregnant females experiencing HG in the ER.

Determinants of macrosomia among newborns delivered in northwest Ethiopia: a case–control study

Objective

Macrosomia is associated with the risk of mortality and morbidity in neonates and their mothers. Despite the considerable public health effect of macrosomia, evidence on the determinants of macrosomia is limited in Northwest Ethiopia in general and in Amhara region in particular. Therefore, this study aimed to identify determinants of macrosomia among newborns delivered in referral hospitals in 2020 in Amhara region, Northwest Ethiopia.

Methods

A facility-based unmatched case-control study was conducted among 279 mothers and their newborns in Amhara region referral hospitals. Newborns weighing 4000 g and above and between 2500 and 3999 g were considered cases and controls, respectively. Bivariable and multivariable binary logistic regression were used to identify the determinants of macrosomia.

Results

In total, 273 of 279 mothers and their newborns (97.8% response rate) were included. The mean birth weights of cases and controls were 4312.97 ± 357.53 g and 3161.92 ± 452.12 g, respectively. Weight gain over pregnancy, antenatal follow up, physical activity during pregnancy, and neonate sex were the main determinants of macrosomia.

Conclusion

The main determinants of macrosomia were determined in this study. Government should place special emphasis on reducing the modifiable factors of macrosomia.

Can alanine aminotransferase measured in early pregnancy predict macrosomia?

Non-alcoholic fatty liver disease (NAFLD) is a part of the metabolic syndrome and is associated with adverse pregnancy outcomes. The aim of this study was to determine whether unexplained elevated ALT in early pregnancy has any effect in the prediction of large for gestational age (LGA) infants. In this study, the relationship between birth weights of LGA babies and babies with normal weight for gestational age (AGA) and ALT values measured in early pregnancy was evaluated. While a positive, moderately strong, statistically significant correlation was found between infant birth weight and ALT levels in LGA babies this correlation was continued when GDM was not detected and ALT levels were below 36 U/L. Foetal macrosomia, which can develop in advanced gestational weeks, can be predicted with this cheap, easy and simple method that can be checked in the first trimester and pregnancy follow-up can be shaped accordingly.IMPACT STATEMENTWhat is already known on this subject? It is suggested that asymptomatic high ALT values measured in the first trimester can predict a macrosomic foetus.What do the results of this study add? Asymptomatic elevated ALT values measured in the first trimester can predict a macrosomic foetus.What are the implications of these findings for clinical practice and/or further research? Macrosomic foetus development can be predicted with abnormal results obtained with this simple, cheap and easy measurement method measured in the first trimester and pregnancy follow-up can be managed accordingly.

A presentation of adenovirus with hypokalemia and rhabdomyolysis in pregnancy

Background

Adenovirus infection is usually mild in presentation. However during pregnancy, the course can be more severe.

Case

A 21-year-old woman in her second pregnancy presented with abdominal pain, vomiting, and fevers at 34 weeks and 4 days of gestation. Her respiratory pathogen panel on nasopharyngeal secretions was positive for adenovirus. Electrolytes were notable for hypomagnesaemia and persistent hypokalemia (nadir of 2.6 mmol/L) despite repletion but otherwise unremarkable. During her course, she developed rhabdomyolysis. During routine fetal monitoring at 35 weeks and 6 days of gestation, prolonged fetal bradycardia was identified, and an emergency caesarean delivery was performed. The infant had no clinical or laboratory evidence of adenovirus infection. The patient had a protracted clinical course but recovered with supportive care.

Conclusion

Adenovirus can present with severe complications in a pregnant woman including hypokalemia and rhabdomyolysis. The mainstay of treatment is supportive care and monitoring of electrolyte abnormalities and renal function.

Physiological changes in pregnancy and their influence on the endocrine investigation

BACKGROUND

Physiological changes in pregnancy may result in significant alterations in endocrine hormone profiles, serum and urine electrolytes and endocrine gland morphology on imaging. Pregnancy-specific pathophysiological processes may also affect the results for endocrine tests. Investigation of endocrine disorders in pregnancy requires knowledge of these changes and awareness of the safety of dynamic hormone testing and imaging for the mother and foetus.

OBJECTIVE

This review seeks to outline the important physiological changes in pregnancy affecting reference intervals of basal and dynamic endocrine tests in pregnancy and the scenarios in which these changes are clinically significant, the pregnancy-specific disorders that may affect the investigation of endocrine disorders, and the safety of dynamic testing and imaging.

CONCLUSION

Awareness of the effect of physiological changes, and the potential impact of pregnancy-specific disorders of endocrine tests, and the safety of imaging is crucial to the management of endocrine disorders in pregnancy.

Correlation of Maternal Neck/Waist Circumferences and Fetal Macrosomia in Low-Risk Turkish Pregnant Women, a Preliminary Study

Goals: Our aim in this study was to determine if the maternal neck and waist circumference measured in the first three months of pregnancy were effective in prediction of fetal macrosomia.Material and methods In this retrospective cohort study; body mass index, neck circumference (NC) and waist circumference (WC) was measured in low risk pregnant women at 11-13+^6th weeks of pregnancy.Results Among the 361 women, 8% of newborns were over 4000 grams. The rate of fetal macrosomia increased with the increased NC and WC. In ROC analysis, optimum cutoff value of NC was >36.5 cm to predict fetal macrosomia with 68.97% sensitivity and 66.97% specifity and for WC it was >88 cm with 62.07% sensitivity and 61.26% specifity.Conclusion Risk of fetal macrosomia increased with the increased maternal NC and WC.

Hyperemesis gravidarum induced refeeding syndrome causes blood cell destruction: a case report and literature review

Background

Hyperemesis gravidarum (HG) is a common complication during pregnancy, however, HG associated simultaneous onset of blood cell destruction due to electrolyte abnormalities is rare. In this case, a woman with refeeding syndrome (RFS) secondary to electrolyte abnormalities caused by severe HG was diagnosed and managed in our hospital.

Case presentation

A 29-year old woman was sent to the local hospitals because of severe HG with appetite loss, weight reduction, general fatigue, and she was identified to have severe electrolyte abnormalities. However, the electrolyte abnormalities were not corrected promptly, and then she had the symptoms of stillbirth, altered mental status, visual hallucination, hemolytic anemia and thrombocytopenia. After transferred to our hospital, we continued to correct the electrolyte abnormalities and the labor induction was performed as soon as possible. The symptoms of blood cell destruction were relieved obviously, and the patient discharged four days later. The electrolyte disturbances and physio-metabolic abnormalities caused by HG helped us diagnose this case as RFS.

Conclusions

This case emphasizes that patients with RFS should be diagnosed appropriately and intervened promptly in order to prevent electrolyte imbalance induced blood cell destruction.

Life-threatening complications of hyperemesis gravidarum

Hyperemesis gravidarum (HG) refers to severe nausea and emesis noted during pregnancy. However, no consensus exists on the specific diagnostic criteria that can be used for this condition. The aim of the present systematic review was to summarize the available evidence regarding the severe complications observed during HG with a heightened risk of fatality. A systematic search was conducted on PubMed, Cochrane Library, EMBASE and WILEY databases for the relevant publications regarding the severe and life-threatening complications of HG. The search terms were as follows: '(Hyperemesis gravidarum)' AND ('complications' OR 'severe' OR 'adverse pregnancy outcomes' OR 'stroke' OR 'seizures' OR 'Wernicke's encephalopathy' OR 'arrhythmias' OR 'pneumomediastinum' OR 'coagulopathy' OR 'electrolytic imbalance'). Abstracts, conference presentations, letters to the editor, studies written in languages other than English and editorials were all excluded. This search identified 43 studies analyzing life-threatening complications of HG, of which 11, seven, eight and 17 articles analyzed neurological, cardiovascular, thoracic and systemic complications, respectively. Reports on life-threatening complications were exceptionally rare in HG. The most frequent severe complications noted were Wernicke's encephalopathy, electrolyte imbalance and vitamin K deficiency. The low mortality rate for patients with HG over the last decade could be explained by the high efficiency of modern therapy, and the precise management of every complication according to current guidelines.

Does metabolomic profile differ with regard to birth weight?

BACKGROUND

Macrosomia and child obesity are growing health-care issues worldwide. The purpose of the study was to evaluate how extremely high or low birth weight affects metabolic markers evaluated in newborn screening.

METHODS

The study was register-based and included full-term singletons born in Iceland from 2009 to 2012 with newborn screening samples taken 72-96 h after birth. Three groups based on birth weight were compared: low birth weight (<2500 g), appropriate-for-gestational age, and extreme macrosomia (≥5000 g). The comparison was adjusted for possible confounding factors.

RESULTS

Compared to appropriate-for-gestational age neonates, both low birth weight and extreme macrosomia were associated with higher levels of glutamic acid. The amino acids alanine and threonine were increased in low birth weight neonates. Free carnitine and some medium- and long-chain acylcarnitines were higher in low birth weight infants. Hydroxybutyrylcarnitine was lower in low birth weight infants, but higher in extremely macrosomic neonates. Acetylcarnitine was higher in low birth weight and extremely macrosomic neonates. Succinylcarnitine was lower and hexadecenoylcarnitine higher in macrosomic newborns.

CONCLUSION

Low birth weight and extremely macrosomic neonates show distinctive differences in their metabolomic profile compared to appropriate-for-gestational age newborns. The differences are not explained by gestational age.

IMPACT

The key message of this article is that both low birth weight and extremely macrosomic newborns show dissimilar metabolomic profiles compared to appropriate-for-gestational age neonates. The article contributes to knowledge on what affects evaluation of results in newborn screening. The impact of this article is to provide information on metabolism at both ends of the birth weight range after accounting for confounding factors including gestational age.

The role of fetal head circumference in the formation of obstetric anal sphincter injuries following vacuum deliveries among primiparous women

PURPOSE

To evaluate the association of sonographic fetal head circumference (HC) with obstetric anal sphincter injury (OASIS) occurrence among primiparous women who underwent vacuum-assisted delivery (VAD).

METHODS

A retrospective study of all primiparous women who delivered at term by VAD between 2011 and 2019 and underwent ultrasound with fetal biometry within 1 week prior to delivery. Women who suffered OASIS were compared to women without OASIS.

RESULTS

Overall, 74 of 3222 (2.3%) primiparous women suffered an OASIS. As compared with control, women with OASIS were younger (median 28 vs. 30 years, p = 0.001), had higher BMI (median 28.2 vs. 26.9 kg/m², p = 0.03), and had a longer second stage of labor (median 190 vs. 168 min, p = 0.01). Fetal head circumference was larger in the OASIS group (mean 334 vs. 330 mm, p = 0.03), occiput posterior fetal head position was more prevalent (12 (16%) vs. 232 (7.4%), OR [95% CI]: 2.43 (1.29-4.57), p = 0.004), and the rate of mediolateral episiotomy performed was lower (58 (78.0%) vs. 2777 (88.2%), OR [95% CI]: 0.48 (0.27-0.85), p = 0.01). Multivariate regression modeling identified higher fetal HC (aOR [95% CI] 1.03 (1.001-1.06), p = 0.04) and occiput posterior (aOR [95% CI] 2.5 (1.16-5.71), p = 0.01) as independently positively associated with OASIS. Mediolateral episiotomy and maternal age were independently negatively associated with an OASIS (aOR [95% CI] 0.39 (0.18-0.85), p = 0.01); aOR [95% CI] 0.4 (0.17-0.60), p = 0.001).

CONCLUSIONS

Sonographic large fetal HC is associated with OASIS occurrence during VAD. The only modifiable predictor of OASIS detected was mediolateral episiotomy, found to be protective against OASIS.

Which way is better to deliver the very heavy baby: mode of delivery, maternal and neonatal outcome

PURPOSE

Currently there are no existing data regarding the maternal and neonatal outcomes for nulliparous women delivering neonates with birthweight above 4500 g. We aim to evaluate birth outcome among these subset of parturients.

METHODS

A retrospective study of nulliparous delivering a singleton fetus weighing  ≥ 4500 g in two tertiary medical centers between 2007 and 2018. Women who chose to undergo a trial of labor (TOL) were compared to those who underwent elective cesarean delivery (CD).

RESULTS

Overall, 121 women were included. Seventy eight (65.4%) women elected a TOL while 43 (34.6%) had elective CD. Of women who chose TOL, 46 (59%) delivered with unassisted vaginal delivery, 28 (36%) by intrapartum CD, and 4 (5%) by assisted vaginal delivery, reaching TOL success rate of 64% (50/78). The rates of shoulder dystocia and anal sphincter injury in vaginal deliveries were 5/50 (10%) and 2/50 (4%) respectively. Successful TOL was negatively associated with the presence of gestational diabetes [5 (18%) vs. 0 (0%), OR 0.8 (95% CI 0.7-0.9), p = 0.005], and was positively associated with maternal height (median 170 cm vs. 165 cm, p = 0.002), epidural analgesia [42 (84%) vs. 16 (57%), OR 3.5 (95% CI 1.2-9.8), p = 0.009] and spontaneous onset of labor (38 (76%) vs. 10 (36%), OR 5.7 (95% CI 2.1-15.6), p = 0.001. Neonates born after TOL were more commonly complicated by meconium aspiration syndrome as compared to no TOL (9 (11%) vs. 0 (0%), OR 1.1 (95% CI 1.04-1.22, p = 0.02). Only maternal height was independently associated with successful TOL (aOR 6.9 (95% CI 1.03-46.3, p = 0.04). Maternal and neonatal adverse composite outcomes were associated with gestational hypertensive disorders (10 (50%) vs. 5 (5%). OR 19.2 (5.5-67.4), p < 0.001) and with delivery before 40 weeks (9 (57%) vs, 86 (82%), OR 3.5 (95% CI 1.2-10.6, p = 0.02), respectively.

CONCLUSIONS

Trial of vaginal delivery in nulliparous with fetuses ≥ 4500 g was associated with a high failure rate, with only two thirds of parturients achieving successful vaginal delivery. Nevertheless, neonatal outcomes mostly did not differ according to the mode of delivery. Maternal height was the only factor associated with successful vaginal delivery.

Trends in the incidence of fetal macrosomia and its phenotypes in the United States, 1971-2017

PURPOSE

Studies have reported a surge in the prevalence of obesity among various demographic groups including pregnant women in the U.S. Given the association between maternal obesity and risk of fetal macrosomia, we hypothesized that the incidence of fetal macrosomia will be on the rise in the U.S. We examined trends in fetal macrosomia and macrosomia phenotypes in the U.S. among singleton live births within the gestational age of 28-42 weeks inclusive.

METHODS

This was a retrospective cohort study covering the period 1971-2017 using U.S. Natality Data files. We applied Joinpoint regression models to derive the average annual percentage change in the outcome. We measured incidence and trends of fetal macrosomia which was defined as birth weight ≥ 4000 g. We further subdivided macrosomia into its phenotypes as previously recommended: Grade 1 (4000-4499 g), Grade 2 (4500-4999 g) and Grade 3 (≥ 5000 g).

RESULTS

A total of 147,331,305 singleton births over the entire study period of 47 years were analyzed. From a baseline incidence of 8.84%, the rate of fetal macrosomia declined to 8.07% by the end of the study representing a drop of 8.70% in relative terms. The greatest drop was among infants with Grade 3 macrosomia, the most severe and lethal phenotype. The most impactful factors were maternal age and gestational weight gain.

CONCLUSION

This study is the largest population-based study conducted regarding fetal macrosomia. The rate of fetal macrosomia declined over the previous 5 decades with the most substantial drop observed in the phenotype with the worst prognosis.

Pregnancy Outcomes of Women Additionally Diagnosed as Gestational Diabetes by the International Association of the Diabetes and Pregnancy Study Groups Criteria

BACKGROUND

We investigated the pregnancy outcomes in women who were diagnosed with gestational diabetes mellitus (GDM) by the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria but not by the Carpenter-Coustan (CC) criteria.

METHODS

A total of 8,735 Korean pregnant women were identified at two hospitals between 2014 and 2016. Among them, 2,038 women participated in the prospective cohort to investigate pregnancy outcomes. Diagnosis of GDM was made via two-step approach with 50-g glucose challenge test for screening followed by diagnostic 2-hour 75-g oral glucose tolerance test. Women were divided into three groups: non-GDM, GDM diagnosed exclusively by the IADPSG criteria, and GDM diagnosed by the CC criteria.

RESULTS

The incidence of GDM was 2.1% according to the CC criteria, and 4.1% by the IADPSG criteria. Women diagnosed with GDM by the IADPSG criteria had a higher body mass index (22.0±3.1 kg/m² vs. 21.0±2.8 kg/m², P<0.001) and an increased risk of preeclampsia (odds ratio [OR], 6.90; 95% confidence interval [CI], 1.84 to 25.87; P=0.004) compared to non-GDM women. Compared to neonates of the non-GDM group, those of the IADPSG GDM group had an increased risk of being large for gestational age (OR, 2.39; 95% CI, 1.50 to 3.81; P<0.001), macrosomia (OR, 2.53; 95% CI, 1.26 to 5.10; P=0.009), and neonatal hypoglycemia (OR, 3.84; 95% CI, 1.01 to 14.74; P=0.049); they were also at an increased risk of requiring phototherapy (OR, 1.57; 95% CI, 1.07 to 2.31; P=0.022) compared to the non-GDM group.

CONCLUSION

The IADPSG criteria increased the incidence of GDM by nearly three-fold, and women diagnosed with GDM by the IADPSG criteria had an increased risk of adverse pregnancy outcomes in Korea.

Hyperemesis gravidarum followed by refeeding syndrome causes electrolyte abnormalities induced rhabdomyolysis and diabetes insipidus

Although hyperemesis gravidarum (HG), an extreme form of morning sickness, is a common complication during pregnancy, HG associated simultaneous onset of rhabdomyolysis and diabetes insipidus due to electrolyte abnormalities are rare. A 34-year-old woman with severe HG at 17 weeks of gestation complicated with appetite loss, weight reduction by 17 kg, general fatigue, myalgia, weakness and polyuria was identified to have simultaneous hypophosphatemia (1.6 mg/dL) and hypokalemia (2.0 mEq/L). Appetite recovery and the improvement of the hypophosphatemia (3.2 mg/dL) were observed prior to the first visit to our department. At the admission, she presented polyuria around 7,000~8,000 mL/day with impaired concentrating activity (U-Osm 185 mOsm/L), and abnormal creatine kinase elevation (4,505 U/L). The electrolyte disturbances and physio-metabolic abnormalities in undernourished state due to HG let us diagnose this case as refeeding syndrome (RFS). In this case, abnormal loss by vomiting, insufficient intake and previous inappropriate fluid infusion as well as the development of RFS may accelerate the severity of hypokalemia due to HG. Thus, as her abnormalities were considered as results of rhabdomyolysis and diabetes insipidus due to severe HG associated hypokalemia based on RFS, oral supplementation of potassium chloride was initiated. After 6 days of potassium supplementation, her symptoms and biochemical abnormalities were completely resolved. Severe HG followed by RFS can be causes of electrolyte abnormalities and subsequent complications, including rhabdomyolysis and renal diabetes insipidus. Appropriate diagnosis and prompt interventions including adequate nutrition are necessary to prevent electrolyte imbalance induced cardiac, neuromuscular and/or renal complications.

Changes in biochemical tests in pregnancy and their clinical significance

Interpretation of laboratory investigations relies on reference intervals. Physiological changes in pregnancy may result in significant changes in normal values for many biochemical assays, and as such results may be misinterpreted as abnormal or mask a pathological state. The aims of this review are as follows: 1. To review the major physiological changes in biochemical tests in normal pregnancy. 2. To outline where these physiological changes are important in interpreting laboratory investigations in pregnancy. 3. To document the most common causes of abnormalities in biochemical tests in pregnancy, as well as important pregnancy-specific causes.

Review article: Investigations and the pregnant woman in the emergency department - part 1: Laboratory investigations

Accurate assessment of the pregnant patient in the ED depends on knowledge of physiological changes in pregnancy, and how these changes may impact on pathology tests, appearance on point-of-care ultrasound and electrocardiography. In addition the emergency physician needs to be cognisant of disorders that are unique to or more common in pregnancy. Part 1 of this review addresses potential deviations in laboratory investigation reference intervals resulting from physiological alterations in pregnancy, and the important causes of abnormal laboratory results in pregnancy. Part 2 will address the role of point-of-care ultrasound in pregnancy, physiological changes that may affect interpretation of point-of-care ultrasound, physiological changes in electrocardiography, and the safety of radiological procedures in the pregnant patient.

Hyperemesis Gravidarum: A Review of Recent Literature

BACKGROUND

In the United States, hyperemesis gravidarum is the most common cause of hospitalization during the first half of pregnancy and is second only to preterm labor for hospitalizations in pregnancy overall. In approximately 0.3-3% of pregnancies, hyperemesis gravidarum is prevalent and this percentage varies on account of different diagnostic criteria and ethnic variation in study populations. Despite extensive research in this field, the mechanism of the disease is largely unknown. Although cases of mortality are rare, hyperemesis gravidarum has been associated with both maternal and fetal morbidity. The current mainstay of treatment relies heavily on supportive measures until improvement of symptoms as part of the natural course of hyperemesis gravidarum, which occurs with progression of gestational age. However, studies have reported that severe, refractory disease manifestations have led to serious adverse outcomes and to termination of pregnancies.

SUMMARY

Despite extensive research in the field, the pathogenesis of hyperemesis gravidarum remains unknown. Recent literature points to a genetic predisposition in addition to previously studied factors such as infectious, psychiatric, and hormonal contributions. Maternal morbidity is common and includes psychological effects, financial burden, clinical complications from nutritional deficiencies, gastrointestinal trauma, and in rare cases, neurological damage. The effect of hyperemesis gravidarum on neonatal health is still debated in literature with conflicting results regarding outcomes of birth weight and prematurity. Available therapy options remain largely unchanged in the past several decades and focus on parenteral antiemetic medications, electrolyte repletion, and nutritional support. Most studies of therapeutic options do not consist of randomized control studies and cross-study analysis is difficult due to considerable variation of diagnostic criteria. Key Messages: Hyperemesis gravidarum carries a significant burden on maternal health and US health care. Most published research on pathogenesis is observational and suggests multifactorial associations with hyperemesis gravidarum. Precise, strictly defined criteria for clinical diagnosis are likely to benefit meta-analyses of further research studies regarding pathogenesis as well as therapeutic options.

Non-traumatic rhabdomyolysis: Background, laboratory features, and acute clinical management

Rhabdomyolysis is a relatively rare condition, but its clinical consequences are frequently dramatic in terms of both morbidity and mortality. Although no consensus has been reached so far about the precise definition of this condition, the term rhabdomyolysis describes a rapid breakdown of striated, or skeletal, muscle. It is hence characterized by the rupture and necrosis of muscle fibers, resulting in release of cell degradation products and intracellular elements within the bloodstream and extracellular space. Notably, the percentage of patients with rhabdomyolysis who develop acute kidney injury, the most dramatic consequence, varies from 13% to over 50% according to both the cause and the clinical and organizational setting where they are diagnosed. Despite direct muscle injury (i.e., traumatic rhabdomyolysis) remains the most common cause, additional causes, frequently overlapping, include hypoxic, physical, chemical or biological factors. The conventional triad of symptoms includes muscle pain, weakness and dark urine. The laboratory diagnosis is essentially based on the measurement of biomarkers of muscle injury, being creatine kinase (CK) the biochemical "gold standard" for diagnosis, and myoglobin the "gold standard" for prognostication, especially in patients with non-traumatic rhabdomyolysis. The essential clinical management in the emergency department is based on a targeted intervention to manage the underlying cause, combined with infusion of fluids and eventually sodium bicarbonate. We will present and discuss in this article the pathophysiological and clinical features of non-traumatic rhabdomyolysis, focusing specifically on Emergency Department (ED) management.