Dehydration in acute gastroenteritis

Is Serum Bicarbonate Level Associated With Negative Outcomes in Pediatric Patients?: A Retrospective Cohort Study

OBJECTIVES

Early identification of children at risk for adverse outcomes is important. Serum bicarbonate is easily collected and widely available. We described the relationship between bicarbonate and adverse outcomes in children presenting to the emergency department (ED).

METHODS

We conducted a retrospective cohort study of children aged 0 to 17 years from January 1, 2007, to December 31, 2011, who had a serum bicarbonate measured in the ED. Primary outcome was the predictive ability of bicarbonate for the individual components of the composite outcome that included at least one of the following: intensive care unit admission, assisted ventilation, inotropic support, cardiopulmonary resuscitation, or death. Secondary outcome was the relationship between bicarbonate level of greater and less than 13 mEq/L and the composite outcome.

RESULTS

We reviewed 16,989 charts, of which 432 had an adverse outcome. Receiver operating characteristic curve analysis showed that a bicarbonate level of less than 18.5 mEq/L predicted inotropic support with an area under the curve of 0.69 (95% confidence interval [CI], 0.60-0.77; P < 0.001) and death with an area under the curve of 0.75 (CI, 0.66-0.85; P < 0.001). Significantly more patients with bicarbonate level of less than 13 mEq/L had at least 1 adverse outcome compared with those with bicarbonate level of greater than 13 mEq/L (4.4% vs 2.5%, P = 0.001), odds ratio 1.96 (95% CI, 1.3-2.97).

CONCLUSIONS

Among children presenting to the ED, bicarbonate level of 18.5 mEq/L had fair specificity in predicting inotropic support and death. Negative outcomes are significantly associated with bicarbonate level of less than 13 mEq/L. Bicarbonate should routinely be measured in children at risk of clinical deterioration.

Severity of rotavirus gastroenteritis in an Indian population: report from a 3 year surveillance study

This study investigated the severity of rotavirus gastroenteritis (RVGE) in hospitalized children less than 60 months of age and compared severity in the first five months of life to severity in children 6 to 23 months of age. Results from a 3 year surveillance study show an early peak of rotavirus disease, with 117 (31%) RVGE hospitalizations in children <6 months old. Higher incidence of severe dehydration, acidemia and acidosis at admission and prolonged hospitalization >7 days were seen in infants 0-5 months of age. The findings support the need for consideration of timely immunization or an accelerated immunization schedule with a birth dose to protect this vulnerable age.

Indigenous child health: are we making progress?

We identified 244 relevant articles pertinent to indigenous health (4% of the total) with a steady increase in number since 1995. Most Australian publications in the journal (with a small Indigenous population) have focussed on conditions such as malnutrition, diarrhoeal disease, iron deficiency, rheumatic fever, acute glomerulonephritis and respiratory and ear infections, and in settings where nearly all affected children are Indigenous. In contrast, New Zealand publications (with a large Maori and Pacific Islander population) have addressed important health issues affecting all children but emphasised the over-representation of Maori and Pacific Islanders. Publications in the journal are largely descriptive studies with relatively few systematic reviews and randomised trials. Our review attempts to cover the important Indigenous health issues in our region as represented by articles published in the Journal. The studies do document definite improvements in indigenous child health over the last 50 years.

Does a standardised scoring system of clinical signs reduce variability between doctors' assessments of the potentially dehydrated child?

AIMS

Clinical assessment of dehydration in children is often inaccurate. We aimed to determine if a scoring system based on standardised clinical signs would reduce the variability between doctors' assessment of dehydration.

METHODS

A clinical scoring system was developed using seven physiological variables based on previously published research. Estimated percentage dehydration and severity scores were recorded for 100 children presenting to a Paediatric Emergency Department with symptoms of gastroenteritis and dehydration by three doctors of different seniority (resident medical officer, registrar and consultant). Agreement was measured using intra-class correlation coefficient (ICC) for percentage ratings and total clinical scores and kappa for individual characteristics.

RESULTS

Estimated percentage dehydration ranged from 0-9%, mean 2.96%, across the three groups. Total clinical scores from 0-10, mean 2.20. There was moderate agreement amongst clinicians for the percentage dehydration (ICC 0.40). The level of agreement on the clinical scoring system was identical (ICC 0.40). Consultants gave statistically lower scores than the other two groups (Consultant (Con) vs. Resident P = 0.001, Con vs. Registrar P = 0.013). There was a marked difference in agreement across characteristics comprising the scoring system, from kappa 0.02 for capillary refill time to 0.42 for neurological status.

CONCLUSION

The clinical scoring system used did not reduce the variability of assessment of dehydration compared to doctors' conventional methods. In order to reduce variability improving education may be more important than production of a scoring system as experience appears to be a key determinant in the assessment of a potentially dehydrated child.

Acute and persistent diarrhea

Socially disadvantaged Indigenous infants and children living in western industrialized countries experience high rates of infectious diarrhea, no more so than Aboriginal children from remote and rural regions of Northern Australia. Diarrheal disease, poor nutrition, and intestinal enteropathy reflect household crowding, inadequate water and poor sanitation and hygiene. Acute episodes of watery diarrhea are often best managed by oral glucose-electrolyte solutions with continuation of breastfeeding and early reintroduction of feeding. Selective use of lactose-free milk formula, short-term zinc supplementation and antibiotics may be necessary for ill children with poor nutrition, persistent symptoms, or dysentery. Education, high standards of environmental hygiene, breastfeeding, and immunization with newly licensed rotavirus vaccines are all needed to reduce the unacceptably high burden of diarrheal disease encountered in young children from Indigenous communities.

Critical appraisal of the management of severe malnutrition: 3. Complications

The high case-fatality of severe malnutrition is due to infections, dehydration, electrolyte disturbances and heart failure. We focus on the evidence about managing these complications of severe malnutrition. Signs of circulatory collapse in severely malnourished children should be treated with intravenous or bone marrow infusion of Ringer's lactate with additional dextrose and potassium at a rate 20-40 mL/kg fast with close monitoring of vital signs. Recommendations for slow or restricted fluids in the face of shock are unsafe, and hypotonic or maintenance solutions must be avoided to prevent hyponatraemia. However, the evidence that severely malnourished children do not tolerate excessive fluid administration is good, so caution must be exercised with regards to fluids in the initial phase of treatment. There is also good evidence that wide spectrum antibiotics need to be given empirically for severe malnutrition to prevent the otherwise unavoidable early mortality. There is a need for improved protocols for tuberculosis diagnosis, HIV management and treatment of infants under 6 months with severe malnutrition. The contribution of environmental enteropathy to poor growth and nutrition during the weaning period means that there should be more priority on improving environmental health, particularly better hygiene and less overcrowding. A T-cell mediated enteropathy contributes to growth failure and malnutrition, and it is related to environmental contamination of enteric organisms in the weaning period rather than allergic responses.

Changes in Metabolic and Hematologic Laboratory Values With Ascent to Altitude and the Development of Acute Mountain Sickness in Nepalese Pilgrims

OBJECTIVE

During August of each year, thousands of Nepalese religious pilgrims ascend from 2050 m to 4500 m in 1 to 3 days. Our objectives were to evaluate the incidence of acute mountain sickness (AMS) among this large group of native people, to explore changes in serum electrolytes as subjects ascend to high altitude, and to attempt to determine whether decreased effective circulating volume is associated with the development of AMS.

METHODS

This was a prospective study with 2 parts. In the first part, demographic, physiologic, and laboratory data were collected from a cohort of 34 pilgrims at both moderate (2050 m) and high altitude (4500 m). Changes that occurred with ascent were compared in subjects who did and did not develop AMS. The second part was a cross sectional study of a different group of 57 pilgrims at the high-altitude site to further determine variables associated with AMS.

RESULTS

In the cohort of 34 subjects, Lake Louise score, heart rate, respiratory rate, blood urea nitrogen (BUN), BUN:creatinine ratio, and pH increased at high altitude, whereas oxygen saturation, bicarbonate, creatinine, and PCO2 decreased. Sixteen of these 34 subjects (42%) were diagnosed with AMS; these patients had a statistically significantly lower hematocrit, oxygen saturation, and self-reported water consumption than those without AMS. Of the 57 subjects enrolled in the cross sectional study, 31 (54%) were diagnosed with AMS. These pilgrims had higher heart rates and BUNs than did their non-AMS counterparts.

CONCLUSIONS

Fifty-two percent of the subjects developed AMS. With ascent to altitude, subjects showed some evidence of decreased effective circulating volume, though there were no clinically significant changes. The data did not show whether decreased circulating volume is a significant risk factor in the development of AMS at high altitude.

2. Acute infectious diarrhoea and dehydration in children

Gastroenteritis in children is still a common reason for consulting a general practitioner and for hospital admission. Rotavirus is the most common cause of gastroenteritis in children and accounts for half of all hospital admissions for severe acute infectious diarrhoea. Most children with gastroenteritis do not develop dehydration and can be treated at home. Children with mild to moderate dehydration should be treated with low osmolarity oral rehydration solutions, and those with severe dehydration or shock need to be admitted for administration of intravenous fluids. Lactose-free feeds should not be routinely used after acute gastroenteritis, but there is some evidence that a lactose-free diet may reduce the duration of diarrhoea. Antimotility drugs are rarely indicated in children with gastroenteritis, as the potential risks outweigh the benefits. The development of a rotavirus vaccine would provide huge public health benefits and cost savings. Other preventive strategies include educating people about personal and food hygiene and encouraging breastfeeding.

Increased nitric oxide production in acute diarrhoea is associated with abnormal gut permeability, hypokalaemia and malnutrition in tropical Australian aboriginal children

Australian Aboriginal children hospitalized with diarrhoeal disease have severe manifestations with acidosis, hypokalaemia, osmotic diarrhoea and abnormal small bowel permeability. Nitric oxide (NO) production is increased in diarrhoeal disease, but its relationship to mucosal function and diarrhoeal complications is not known. We examined the relationship between NO production and complications of acute diarrhoea in Aboriginal and non-Aboriginal children between February 1998 and February 2000. We enrolled 318 children admitted to Royal Darwin Hospital into one of three groups: acute diarrhoea, non-diarrhoeal controls with no inflammatory illness, and non-diarrhoeal controls with inflammatory illness. Nitric oxide production was measured by urine nitrate-creatinine (NOx/Cr) excretion on a low nitrate diet. Small bowel intestinal permeability was measured by the lactulose-rhamnose (L/R) ratio on a timed blood specimen. The NOx/Cr ratios were markedly elevated in Aboriginal diarrhoeal cases (geometric mean [GM] = 1.23, 95% confidence interval [95% CI] 1.07-1.44), lowest in non-Aboriginal non-inflammatory controls (GM = 0.13, 95% CI 0.10-0.16) and intermediate in all other groups (GM = 0.35, 95% CI 0.28-0.43). Convalescent levels (day 5) in the Aboriginal diarrhoeal group (GM = 1.02, 95% CI 0.82-1.28) were slower to fall than L/R ratios. Multivariate analysis in the diarrhoeal group indicated that high NO production was associated with abnormal permeability, hypokalaemia and malnutrition, but not with the severity of diarrhoea, acidosis or osmotic diarrhoea. We concluded that increased NO production may contribute to impaired mucosal barrier function and hypokalaemia in acute gastroenteritis, which may be the cost of the known gut-protective and antimicrobial effects mediated by NO in acute intestinal inflammation.