The consensus of the Asociación Mexicana de Gastroenterología on the diagnosis and treatment of gastroesophageal reflux and gastroesophageal reflux disease in infants

Gastroesophageal reflux (GER) is a frequent normal phenomenon in children of any age. It is more common in infants, in whom the majority of episodes are short-lived and cause no other symptoms or complications, differentiating it from gastroesophageal reflux disease (GERD). The diagnosis and management of GER and GERD continue to be a challenge for the physician. Therefore, the aim of the Asociación Mexicana de Gastroenterología was to adapt international documents to facilitate their adoption by primary care physicians, with the goal of standardizing quality of care and reducing the number of diagnostic tests performed and inappropriate medication use. The ADAPTE methodology was followed, and the recommendations were approved utilizing the Delphi strategy. The executive committee carried out the review of the guidelines, position papers, and international reviews that met the a priori quality criteria and possible applicability in a local context. The recommendations were taken from those sources and adapted, after which they were approved by the working group. The consensus consists of 25 statements and their supporting information on the diagnosis and treatment of GER and GERD in infants. The adapted document is the first systematic effort to provide an adequate consensus for use in Mexico, proposing a practical approach to and management of GER and GERD for healthcare providers.

Preventing Cardiac Arrest in the Pediatric Cardiac Intensive Care Unit Through Multicenter Collaboration

Importance

Preventing in-hospital cardiac arrest (IHCA) likely represents an effective strategy to improve outcomes for critically ill patients, but feasibility of IHCA prevention remains unclear.

Objective

To determine whether a low-technology cardiac arrest prevention (CAP) practice bundle decreases IHCA rate.

Design, Setting, and Participants

Pediatric cardiac intensive care unit (CICU) teams from the Pediatric Cardiac Critical Care Consortium (PC4) formed a collaborative learning network to implement the CAP bundle consistent with the Institute for Healthcare Improvement framework; 15 hospitals implemented the bundle voluntarily. Risk-adjusted IHCA incidence rates were analyzed across 2 time periods, 12 months (baseline) and 18 months after CAP implementation (intervention) using difference-in-differences (DID) regression to compare 15 CAP and 16 control PC4 hospitals that chose not to participate in CAP but had IHCA rates tracked in the PC4 registry. Patients deemed at high risk for IHCA, based on a priori evidence-based criteria and empirical hospital-specific criteria, were selected to receive the CAP bundle. Data were collected from July 2018 to December 2019, and data were analyzed from March to August 2020.

Interventions

CAP bundle included 5 elements developed to promote increased situational awareness and communication among bedside clinicians to recognize and mitigate deterioration in high-risk patients.

Main Outcomes and Measures

Risk-adjusted IHCA incidence rate across all CICU admissions (IHCA events divided by all admissions).

Results

The bundle was activated in 2664 of 10 510 CAP hospital admissions (25.3%); admission characteristics were similar across study periods. There was a 30% relative reduction in risk-adjusted IHCA incidence rate at CAP hospitals (intervention period: 2.6%; 95% CI, 2.2-2.9; baseline: 3.7%; 95% CI, 3.1-4.0), but no change at control hospitals (intervention period: 2.7%; 95% CI, 2.3-2.9; baseline: 2.7%; 95% CI, 2.2-3.0). DID analysis confirmed significantly reduced odds of IHCA among all admissions at CAP hospitals compared with control hospitals during the intervention period vs baseline (odds ratio, 0.72; 95% CI, 0.56-0.91; P = .01). DID odds ratios were 0.72 (95% CI, 0.53-0.98) for the surgical subgroup, 0.74 (95% CI, 0.48-1.14) for the medical subgroup, and 0.72 (95% CI, 0.50-1.03) for the high-risk admission subgroup at CAP hospitals after intervention. All-cause risk-adjusted mortality rate did not change after intervention.

Conclusions and Relevance

Implementation of this CAP bundle led to significant IHCA reduction across multiple pediatric CICUs. Future studies may determine if this bundle can be effective in other critically ill populations.

NWChem: Past, present, and future

Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

The abdominal compartment syndrome in patients with burn injury

INTRODUCTION

Intra-abdominal hypertension (IAH) and subsequent abdominal compartment syndrome (ACS) in burned patients is common. This sequence of events typically occurs in patients with larger burns receiving high volume fluid resuscitation.

METHODS

A review of the literature was performed. The National Library of Medicine (PUBMED) was queried for "Burn" and "Abdominal Compartment Syndrome". Twenty-nine articles were retained for study.

RESULTS

Abdominal pressure monitoring is appropriate in all patients with burns that require significant volume resuscitation (>30% total burned surface area- TBSA). Prevention of ACS in burns includes limiting fluid resuscitation, burn escharotomy, and percutaneous drainage when abdominal pressures are reaching perilous levels. Treatment includes all of the above and in addition, decompressive laparotomy when needed. However, despite decompressive laparotomy, mortality rates among burn victims with ACS remain unacceptably high.

CONCLUSION

Increasing amounts of volume delivery are associated with an increased risk of IAH. Therefore, intra-abdominal pressure should be monitored in all burn patients requiring massive fluid resuscitation. Escharotomy, paracentesis, and decompressive laparotomy may all be needed to counter the side effects of appropriate fluid resuscitation in the severely burned patient. Nevertheless, the prognosis in burn patients developing ACS is grim.

The abdominal compartment syndrome in patients with burn injury

INTRODUCTION

Intra-abdominal hypertension (IAH) and subsequent abdominal compartment syndrome (ACS) in burned patients is common. This sequence of events typically occurs in patients with larger burns receiving high volume fluid resuscitation.

METHODS

A review of the literature was performed. The National Library of Medicine (PUBMED) was queried for "Burn" and "Abdominal Compartment Syndrome". Twenty-nine articles were retained for study.

RESULTS

Abdominal pressure monitoring is appropriate in all patients with burns that require significant volume resuscitation (>30% total burned surface area-TBSA). Prevention of ACS in burns includes limiting fluid resuscitation, burn escharotomy, and percutaneous drainage when abdominal pressures are reaching perilous levels. Treatment includes all of the above and in addition, decompressive laparotomy when needed. However, despite decompressive laparotomy, mortality rates among burn victims with ACS remain unacceptably high.

CONCLUSION

Increasing amounts of volume delivery are associated with an increased risk of IAH. Therefore, intra-abdominal pressure should be monitored in all burn patients requiring massive fluid resuscitation. Escharotomy, paracentesis, and decompressive laparotomy may all be needed to counter the side effects of appropriate fluid resuscitation in the severely burned patient. Nevertheless, the prognosis in burn patients developing ACS is grim.

Structural criteria for the rational design of selective ligands. 3. Quantitative structure-stability relationship for iron(III) complexation by tris-catecholamide siderophores

We present an extended MM3 model for catecholamide ligands and their Fe(3+) complexes and the application of this model to understand how ligand architecture effects Fe(3+) binding affinity. Force field parameters were fit to geometries and energies from electronic structure calculations, and to crystal structure data. Optimized geometries are reported for phenol, acetamide, the phenol-phenol dimer, the acetamide-phenol dimer, and N-methylsalicylamide (HMSA) at the BLYP/DZVP2/A2 level of theory. Optimized geometries and relative energies are reported for the pseudo-octahedral ground state and the trigonal planar transition state of [Fe(CAT)(3)](3)(-) at the VWN/DZVP2/A1 level of theory. The MM3 model is validated by comparison of calculated structures with crystal structures containing 1,2-dihydroxybenzene (H(2)CAT) and 2,3-dihydroxy-N-methylbenzamide (H(2)MBA) fragments, crystal structures of [Fe(CAT)(3)](3)(-) and tris-catecholamide Fe(3+) complexes, and comparison of MM3 (6.8 kcal/mol) and VWN (5.9 kcal/mol) barriers for intramolecular octahedral inversion in [Fe(CAT)(3)](3)(-). The MM3 model also rationalizes the higher inversion barrier (14 to 18 kcal/mol) reported for [Ga(N,N-diisopropylterephthalamide)(3)](3)(-) ([Ga(DIPTA)(3)](3)(-)). Conformational searches were performed on enterobactin (H(6)ENT), 1,3,5-tris(2,3-dihydroxybenzamidomethyl)-2,4,6-triethylbenzene (H(6)EMECAM), 1,3,5-tris(2,3-dihydroxybenzamidomethyl)-2,4,6-trimethylbenzene (H(6)MMECAM), 1,3,5-tris(2,3-dihydroxybenzamidomethyl)benzene (H(6)MECAM), and 1,5,9-N,N',N' '-tris(2,3-dihydroxybenzoyl)cyclotriazatridecane (H(6)-3,3,4-CYCAM) and Fe(3+) complexes with each of these ligands. A conformational search also was done on the Fe(3+) complex with the 2,2',2' '-tris(2,3-dihydroxybenzamido)triethylammonium cation (H(7)TRENCAM(+)). The relationship between calculated steric energies and measured thermodynamic quantities is discussed, and linear correlations between formation constants and steric energy differences are reported. Extrapolation to zero strain predicts formation constants 8 +/- 5 orders of magnitude higher than that exhibited by ENT (10(49)) are possible. This prediction is supported by a formation constant of 10(63) estimated from the formation constant of [Fe(2,3-dihydroxy-N,N-dimethylbenzamide)(3)](3)(-) ([Fe(DMBA)(3)](3)(-)) by considering the entropic consequences of connecting three DMBA ligands to a rigid backbone. Structural criteria for the identification of improved tris-catecholate ligand architectures are presented.

Survey of genetic screening for oocyte donors

OBJECTIVE

To describe current screening practices of oocyte donation programs in the Society for Assisted Reproductive Technologies (SART).

DESIGN

Descriptive data from a mailed questionnaire.

SETTING

Academic medical center.

PARTICIPANT(S)

In vitro fertilization programs in SART.

INTERVENTION(S)

Survey mailed to IVF programs in the SART registry.

MAIN OUTCOME MEASURE(S)

Current practices, opinions, and genetic criteria for oocyte donor selection.

RESULT(S)

Results from 159 of 229 (69%) eligible oocyte donation programs are described. Most centers (70%) completed fewer than 25 cycles and used both anonymous and directed donors. There was considerable variability in limits on numbers of cycles or births allowed per donor, with many centers having no limits. As well, the use of well-established screening tests for genetic disorders, such as sickle cell anemia and cystic fibrosis, varied considerably. Consultation with a geneticist was possible at most (89%) centers and specifically mentioned by some centers as a means to help make decisions.

CONCLUSION(S)

Most programs follow recommendations made by the American Society of Reproductive Medicine (ASRM) for screening of gamete donors, but a significant percentage does not use well-established testing. The widespread availability of genetic consultation should promote responsible screening practices.

Brachydactyly-short stature-hypertension (Bilginturan) syndrome: report on two families

We report on two families with autosomal dominant brachydactyly of hands and feet and hypertension. All affected members of the first family had proportionate short stature. However, the propositus and the affected relatives in the second family were only short compared to unaffected relatives. The hypertension was medically responsive in all cases. The propositus in the second family had poor compliance and a striking generalized vasculopathy. All patients were of normal intelligence and had a normal facial appearance. The brachydactyly-short stature-hypertension syndrome was first reported by Bilginturan et al. [1973] in a Turkish family and the families reported by us are Caucasian and Hispanic. The gene causing this condition in the original Turkish family was recently mapped to 12p. Our report expands our existing knowledge and the ethnic diversity of this syndrome.

Maternal serum analyte levels in pregnancies with fetal Down syndrome resulting from translocations

OBJECTIVE

Our purpose was to determine whether pregnancies affected by fetal Down syndrome resulting from Robertsonian translocations are associated with second-trimester maternal serum analyte levels different from those resulting from fetal trisomy 21.

STUDY DESIGN

Pregnancies with Down syndrome caused by Robertsonian translocations were identified through the cytogenetics laboratories at the participating institutions. Those with maternal serum screening values between 15 and 20 weeks were evaluated.

RESULTS

Eleven cases of fetal Down syndrome caused by Robertsonian translocations were identified. The median alpha-fetoprotein, unconjugated estriol, and human chorionic gonadotropin levels were 0.68, 0.67, and 2.83 multiples of the median, respectively. These analyte levels are similar to those for fetal trisomy 21.

CONCLUSIONS

These data suggest that Down syndrome resulting from either Robertsonian translocations or trisomy 21 will be detected in a similar percentage of cases because the second-trimester maternal serum analyte levels are similar.

X-linked mental retardation with thin habitus, osteoporosis, and kyphoscoliosis: linkage to Xp21.3-p22.12

We reevaluated a family previously described as having nonspecific X-linked mental retardation (XLMR) by Snyder and Robinson [1969: Clin Pediatr 8:669-674] (MIM 309583). Clinical and DNA studies were conducted on 17 relatives, including 6 males with mild-to-moderate mental retardation, 3 carrier females, and 8 normal males. In contrast to the normal appearance and minimal clinical findings reported 22 years ago, affected males were found to have a characteristic set of clinical findings. These developed gradually over the first 2 decades, and included thin body build with diminished muscle mass, osteoporosis and kyphoscoliosis, slight facial asymmetry with a prominent lower lip, nasal speech, high narrow or cleft plate, and long great toes. Carrier females were clinically normal. Multipoint linkage analysis indicated linkage to markers distal to the 3' end of DMD (DXS41 and DXS989), with a maximal lod score of 4.7. On the basis of these findings, this entity is redefined as XLMR syndrome.

Distribution of lymphoid nodules, aberrant crypt foci and tumours in the colon of carcinogen-treated rats

Sprague-Dawley rats were given eight weekly subcutaneous injections of 1,2-dimethylhydrazine (DMH) or of vehicle then were sacrificed at 1, 5 or 24 weeks after the last injection of DMH. The locations of pre-existing aggregates of lymphoid nodules (ALNs), the location and multiplicity (size) of aberrant crypt foci (ACF), and the locations of tumours in the colon were determined. A trimodal distribution of pre-existing ALNs along the length of the colon was significantly correlated with the timodal distribution of DMH-induced adenocarcinomas (ACs). A unimodal peak in ACF of all sizes occurred between the sites of two distal ALNs. Thus, the distribution of ACF at 1 or 5 weeks did not correlate with distribution of AC found at 24 weeks. Of the 2640 ACF observed at 1 or at 5 weeks, none were found in the proximal 25% of the colon where ACs eventually occurred. It was concluded that: (1) ALNs play a promotional role in AC formation; (2) the ACs which form in the proximal quarter of the colon seldom if ever form via an ACF precursor; and (3) the location, the number and the size of ACF observed early after DMH exposure did not correlate with the location or predict the incidence of ACs which eventually formed in the colon.

Hepatic cirrhosis and hepatitis: MR imaging enhanced with superparamagnetic iron oxide

Superparamagnetic iron oxide was applied as a reticuloendothelial contrast agent in the diagnosis of cirrhosis and hepatitis in seven patients. Three patients had compensated cirrhosis, and four had active hepatitis. T1- and T2-weighted spin-echo magnetic resonance images were obtained before and 1 hour after the administration of iron oxide. Eight patients without diffuse liver disease served as a control group. Normal liver tissue showed a 75% +/- 9% reduction in signal intensity after the administration of iron oxide, and the liver appeared homogeneously hypointense. Cirrhotic liver tissue showed a smaller response (P less than .05) to iron oxide, with a 52% +/- 13% reduction in liver signal intensity. Inhomogeneous structures could be observed in enhanced images and are thought to represent fibrous bands or regenerating nodules. Liver tissue with active hepatitis showed a markedly reduced response to iron oxide (11% +/- 2%) (P less than .05), and the parenchyma appeared homogeneous. The authors conclude that the uptake of iron oxide particles is inhomogeneously altered in cirrhosis because of structural changes and homogeneously decreased in hepatitis because of functional changes of hepatic parenchyma.

Successful administration of metoclopramide for the treatment of nausea in patients with advanced liver disease. A double-blind controlled trial

A double-blind comparison of metoclopramide versus placebo was performed on 8 cirrhotic patients with nausea (8 cases) and heartburn (3 of the 8 cases) plus mild portal-systemic encephalopathy. As metoclopramide is a dopamine antagonist and dopamine-inadequate neurotransmission has been implicated in the pathogenesis of hepatic coma, this study was also designed to evaluate the effects of metoclopramide on mental state. The study included basal, placebo, metoclopramide, and final periods; each period lasted for 2 wk. Throughout the study patients received 3 g/day of neomycin and an 1800-cal diet containing 40 g/day of mixed protein. During the placebo and metoclopramide phases patients received either two 10-mg metoclopramide capsules t.i.d. or identical placebo capsules. During the study, biweekly liver function tests and portal-systemic encephalopathy parameters were evaluated. A self-evaluation for the presence of nausea and heartburn was also obtained. To monitor the dopamine-blockade effect of metoclopramide, serum prolactin levels were measured. Metoclopramide significantly suppressed the subjective signs of nausea (7 of 8 cases) and heartburn (all cases). Serum prolactin levels were 22 +/- 21 ng/ml, 30 +/- 31 ng/ml, 110 +/- 57 ng/ml (p less than 0.01), and 18.6 +/- 2 ng/ml during basal, placebo, metoclopramide, and final periods, respectively. In spite of these signs of dopamine blockade, no deterioration in mental state, asterixis, electroencephalograms, blood ammonia levels, or psychometric testings were observed. In addition, no extrapyramidal signs were noticeable during any period of the study. One patient presented transient somnolence at the end of the metoclopramide period. We conclude that dopamine blockade is not associated with the appearance of portal-systemic encephalopathy. Metoclopramide is a safe and effective treatment for nausea and heartburn in patients with advanced liver disease.

In vivo steroid studies in luteoma of pregnancy

Endocrine studies were performed in 2 cases of luteoma of pregnancy. Even though both luteomas were discovered incidentally at the time of postpartum tubal ligation and cesarean section, they were found to be functionally active, secreting several androgens. Steroid concentrations were measured in the ovarian vein blood draining the luteoma in one patient and in peripheral vein blood in both patients. Peripheral testosterone, androstenedione, and dihydrotestosterone concentrations were increased severalfold higher than the normal controls and were comparable to the concentrations reported previously in virilizing luteomas. Progesterone, 17 alpha-hydroxyprogesterone, and estradiol concentrations were increased as well. The concentrations in the ovarian vein were significantly greater than those in the peripheral vein, which indicates active secretion of these steroids by the luteoma. In spite of the high concentrations of androgens, neither the mothers nor the infants were virilized. Concentrations of androgenic steroids in the cord blood were in the normal range. Determination of steroid concentrations in the serum, taken at intervals post partum, indicated spontaneous regression of the luteomas.

Plasma levels and urinary excretion of orally administered propantheline bromide in man

After a single oral dose of 30 or 60 mg of propantheline bromide peak plasma levels of the drug were reached within 2 h in six healthy men. Mean peak plasma concentrations were 20.6 and 53.1 ng/ml after 30 mg and 60 mg respectively. The mean apparent absorption and elimination half-lives after 30 mg dose were 0.22 and 1.57 h respectively, and similar half-lives were found at the higher dose level. There was a dose related change in plasma levels and AUCinfinity of the drug, and some 3% to 4% of the administered dose of propantheline bromide was excreted unchanged in urine at each dose level. Comparison of the plasma levels and urinary excretion of the drug with those seen after i.v. administration in an earlier study indicated an apparently low systemic availability of orally administered propantheline bromide. There was tentative evidence of a qualitative relationship between the oral dose administered, plasma concentrations and the effects of propantheline bromide on salivary excretion.