[The influence of the supine and prone positions in the esophageal pH monitoring in very low birth weight infants]

Refluxo gastroesofágico e deglutição em recém nascidos e lactentes: revisão integrativa da literatura

Resumo: O refluxo gastroesofágico é encontrado em 25% dos bebês e pode acarretar vários prejuízos para o desenvolvimento. O objetivo deste trabalho foi realizar uma revisão integrativa da literatura buscando verificar se há publicações relacionando alterações da deglutição com o quadro de refluxo gastroesofágico em recém-nascidos e lactentes. A pesquisa foi realizada consultando os sites da Bireme e da PubMed. Os unitermos utilizados foram refluxo gastroesofágico, recém-nascido e lactente, em português e os correspondentes em inglês. Os descritores foram utilizados pareados, pois isolados abrangia muitos textos com temáticas diferentes da de interesse. Os trabalhos selecionados foram dos últimos dez anos. Não houve limite de tempo. De 1184 artigos da Bireme e 1600 da PubMed analisados a partir da aplicação dos critérios de inclusão e exclusão, restaram 23 artigos, sendo a maioria voltada aos sinais, sintomas e diagnóstico do RGE. Dois artigos abordaram o RGE e a deglutição, demonstrando que pode haver ou não relação entre RGE e disfagia orofaríngea em recém nascidos e lactentes, sendo que a escassez de pesquisas com essa temática demonstrou a necessidade de novos estudos abordando os aspectos patofisiológicos envolvidos.

Ambulatory esophageal pHmetry in healthy dogs with and without the influence of general anesthesia

This research aimed to determine the value of esophageal pH in awake and anesthetized dogs, to evaluate the esophageal pH value in awake dogs, in different body positions, as well as to study the occurrence of gastroesophageal reflux episodes in these positions. Thus, 40 healthy male and female adult dogs with mean body weight of 15.5 ± 4.6 kg were used. Esophageal pHmetry was conducted by inserting a catheter through the oropharynx in 30 dogs (stage 1) anesthetized with acepromazine, propofol and isoflurane, submitted to elective ovariosalpingohysterectomy. In addition, 8-h esophageal pHmetry was carried out transnasally in 10 awake dogs (stage 2), allowed to move and change body positions (lateral and sternal decubitus, and standing position), which were recorded. The mean esophageal pH value was lower (p < 0.01) in the anesthetized dogs (7.3 ± 0.82) than in the awake dogs (8.2 ± 0.3). Only four anesthetized dogs (13.33%) suffered reflux episodes. Reflux was not observed in the awake dogs and no esophageal pH differences were found between the body positions studied. Compared to the alert state, general anesthesia in dogs submitted to the previously mentioned anesthesia protocol causes esophageal pH reduction and predisposes to the occurrence of gastroesophageal reflux episodes. Transnasal pHmetry of 8 h in healthy awake dogs reveals that the esophageal pH value is alkaline and does not vary according to body position. In these animals, decubitus position is not a determining factor for reflux episodes to occur.

Radionuclide scintigraphy in the evaluation of gastroesophageal reflux in symptomatic and asymptomatic pre-term infants

PURPOSE

Gastroesophageal reflux (GER) is very common in pre-term infants. The diagnosis based on symptoms is always questionable. The incidence of GER in symptomatic babies varies from 22% to 85%, but literature regarding the incidence of reflux in asymptomatic pre-term infants is lacking. We used radionuclide scintigraphy to evaluate the incidence of GER in symptomatic as well as asymptomatic pre-term neonates and to assess whether symptoms have any relation with positive scintigraphy.

METHODS

We studied 106 pre-term infants (52 symptomatic, 54 asymptomatic) of less than 34 weeks of gestation, who fulfilled the eligibility criteria. Babies were considered symptomatic in the presence of vomiting, regurgitation, apnea, de-saturations, unexplained bradycardia and recurrent lung collapses. Radionuclide scintigraphy was conducted at post-conceptional age of 32-34 weeks when they were clinically stable for 72 h. Feeding was avoided for 2 h preceding the study. (99m)Tc sulphur colloid was administered in a dose of 1.85 MBq (0.05 mCi) in 1 ml, followed by milk (full feed) through an orogastric tube, prior to imaging under a gamma camera. Reflux was graded as low or high, and reflux episodes during the study were counted.

RESULTS

The incidence of GER in the symptomatic group was 71.2% and in asymptomatic babies 61.1% (p = 0.275). High-grade reflux was more common (71.4%) than low-grade (28.6%) in both groups (p = 0.449). Mean number of reflux episodes in 20 min was 4.4 +/- 2.4 in symptomatic babies and 4.9 +/- 2.2 in asymptomatic babies (p = 0.321). Babies with positive scintigraphy were similar in birth weight, gestation, time to achieve full feeds, weight and age at discharge to those with negative scintigraphy.

CONCLUSIONS

GER is common in pre-term infants of less than 34 weeks gestation. The incidence of positive scintigraphy and grade of reflux is not significantly different in symptomatic vs. asymptomatic babies. Though radionuclide scintigraphy is a simple, quick and non-invasive investigation in suspected cases of GER, positive scintigraphy has no correlation with symptoms.