Ingesta de cáusticos alcalinos: intoxicación frecuente y prevenible, con secuelas graves / Caustic alkali intake: Frequent and preventable poisoning with serious consequences

Las sustancias cáusticas son productos químicos capaces de provocar lesiones de diferente gravedad, según sea la concentración del producto, el tiempo de contacto y la vía de ingreso. La exposición es habitual por tratarse de productos utilizados en el hogar como destapacañerías y/o limpiahornos. Los cáusticos alcalinos producen necrosis por licuefacción de los tejidos. La ingesta causa edema, ulceraciones, sangrado, placas blanquecinas e intensa actividad fibroblástica con cicatrización en tres semanas. El esófago se afecta más que el estómago, en especial cuando se trata de productos sólidos o en escamas. La secuela observada es la estenosis esofágica, la cual puede requerir desde procedimientos de dilatación hasta cirugía de reemplazo, con alta morbilidad. El objetivo del trabajo es presentar tres casos clínicos y sus complicaciones a largo plazo; recordar el manejo inicial del paciente que ingiere cáusticos alcalinos, su seguimiento multidisciplinario y resaltar las medidas de prevención para evitar este tipo de accidentes graves.

Caustic are chemical substances capable of causing different degree of lesions, according to the product concentration, the time and the route of contact. The usual exposure is because of their use as household products such as drain openers and oven cleaners. Caustic alkalis produce tissue liquefaction necrosis. Ingestion causes edema, ulceration, bleeding, whitish plaques and intense fibroblastic activity with healing in three weeks. The esophagus is more affected than the stomach, especially when solids are involved. The observed sequel is esophageal stricture, requiring treatments as dilation or replacement surgery, with high morbilidad. The aim of the paper is to report three clinical cases and their long-term complications; review the initial management of patients who ingested caustic alkali, highlighting its multidisciplinary monitoring and prevention measures to avoid such serious accidents.

Use of sanitizing products: safety practices and risk situations / Uso de produtos saneantes: práticas de segurança e situações de risco

OBJECTIVES: to evaluate the handling and risk factors for poisoning and/or digestive tract injuries associated with the use of sanitizing products at home. METHODS: interviews were conducted in 419 households from different regions, collecting epidemiological data from residents and risk habits related to the use and storage of cleaning products. RESULTS: sanitizing products considered to be a health risk were found in 98% of the households where the research was conducted, and in 54% of cases, they were stored in places easily accessible to children. Lye was found in 19%, followed by illicit products in 39% of homes. In 13% of households, people produced soap, and in 12% they stored products in non-original containers. The use of illicit products and the manufacture of handmade soap were associated with lower educational level of the household owners and with the regions and socioeconomic classes with lower purchasing power. CONCLUSIONS: risk practices such as inadequate storage, manufacturing, and use of sanitizing products by the population evidence the need for public health policies, including educational measures, as a means of preventing accidents. .

OBJETIVOS: avaliar a forma de utilização e os fatores de risco para intoxicações e/ou lesões do trato digestório associados ao uso dos produtos saneantes no domicílio. MÉTODOS: foram realizadas entrevistas em 419 domicílios de diferentes regiões, estabelecendo-se dados epidemiológicos dos moradores e hábitos de risco relacionados à utilização e armazenamento dos produtos de limpeza. RESULTADOS: dos domicílios onde foi realizada a pesquisa, havia produtos saneantes considerados de risco em 98%, sendo que em 54% dos casos, eles estavam armazenados em locais de fácil acesso para crianças. A soda cáustica estava disponível em 19% e os produtos "clandestinos" em 39% das moradias. Em 13% dos domicílios havia o hábito de fazer sabão e em 12% de armazenar os produtos fora da embalagem original. O uso de produtos clandestinos e a fabricação artesanal de sabão estavam associados à baixa escolaridade das donas das casas e às regiões e às classes econômicas de poder aquisitivo mais baixo. CONCLUSÕES: práticas de risco como armazenamento, fabricação e utilização inadequados de produtos saneantes pela população estudada apontam para a necessidade de políticas de saúde pública, incluindo medidas educacionais, como forma de prevenção de acidentes. .

Morphological and functional evaluation of distal esophagus of rabbits submitted to esophageal infusion with caustic soda

The ingestion of caustic substances is an important emergency situation, because of its serious consequences. PURPOSE: To study morphological and functional alterations of the esophagus in rabbits submitted to esophageal infusion of caustic soda (NaOH). METHODS: The 88 rabbits studied were divided into 4 groups: G1 (n=22) were submitted to esophageal infusion with distilled water. G2, G3, and G4 were submitted to esophageal infusion of 2 percent, 4 percent and 6 percent NaOH respectively. Morphological alterations were studied in 12 animals from each group and manometric alterations in the remaining 10. An analysis was made of lower esophageal sphincter (LES) pressure, number and amplitude of contractions in the distal third of the esophagus. These studies were performed before (moment M1) and at 30 minutes, 6 hours, and 24 hours after (moments M2, M3, and M4, respectively) esophageal infusion. RESULTS: Morphological evaluation: G1 - no alterations; G2 - edema, hyperemia, and ecdysis; G3 - enlarged calibre of esophagus, ulcers, ecdysis of mucosa; G4 - lesions similar to G3, but more intense, areas of extensive hemorrhage at M3 and M4. Functional evaluation: LES was higher at M2; the number of distal third lower esophageal contractions in G3, and G4 was lower; and the contraction amplitude was lower in G4. CONCLUSIONS: 1) Esophageal infusion with caustic soda in rabbits is a good experimental model for studying caustic esophagites. 2) Esophageal infusion with NaOH caused lesions in the esophageal wall, with gravity proportional to solution concentration; 3) Infusion caused LES spasm at M2, and reduced both contraction number and amplitude in the distal third of the esophagus.

A ingestão de substâncias cáusticas constitui importante situação de emergência, tendo em vista a gravidade de suas seqüelas. OBJETIVO: Estudar as alterações morfológicas e funcionais do esôfago de coelhos submetidos à infusão esofágica com soda cáustica (NaOH). MÉTODOS: 88 coelhos foram divididos em 4 grupos: G1 (n=22) foi submetido à infusão esofágica com água destilada; G2, G3 e G4 foram submetidos a infusão esofágica com NaOH a 2 por cento, 4 por cento e 6 por cento, respectivamente. Alterações morfológicas foram estudadas em 12 animais de cada grupo e as alterações manométricas, nos 10 animais restantes. Foram feitas análises do esfíncter inferior do esôfago (EIE), número e amplitude das contrações no terço distal do esôfago. Estes estudos foram realizados antes (momento 1 - M1) e aos 30 minutos, 6 horas e 24 horas após a infusão esofágica (momentos M2, M3 e M4, respectivamente). RESULTADOS: Avaliação macroscópica: G1 - sem alterações; G2 - edema, hiperemia e descamação; G3 - aumento do calibre do esôfago, úlceras, descamação da mucosa; G4 - lesões semelhantes as do G3, porém mais intensas, áreas de extensa hemorragia. Avaliação funcional: a pressão no EIE foi mais elevada em M2 no grupo 2; o número das contrações no terço distal do esôfago foi menor em G3 e G4, e a amplitude das contrações foi menor em G4. CONCLUSÕES: 1) a infusão esofágica com NaOH constitui excelente modelo experimental de esofagite cáustica no coelho; 2) a infusão esofágica com NaOH causa lesões na parede do esôfago, com gravidade proporcional a concentração da solução; 3) a infusão causou espasmo do EIE em M2 e redução do número e amplitude das contrações no terço distal do esôfago.

A functional study of caustic strictures of the esophagus in children

The objective of the present study was to assess esophageal motor function in 21 children (7.5 ± 2.9 years) with caustic strictures. Esophageal manometry was performed using a water-infusion system interfaced with a polygraph and displayed on a computer screen. The data were compared with those obtained from 9 healthy children. Radionuclide transit was determined by studying deglutition of a single bolus of 99mTc pertechnetate in 10 ml of water. Non-peristaltic low-amplitude and long-duration waves were the most common findings detected in patients with strictures longer than 20 percent of esophageal length (N = 11). Compared with the control group, these patients presented lower mean amplitude and longer mean duration of waves (24.4 ± 11.2 vs 97.9 ± 23.7 mmHg, P < 0.05, and 6.7 ± 2.4 vs 1.6 ± 0.1 s, P < 0.05, respectively). Six patients presented low-amplitude waves just below the constricted site. Ten children presented delayed esophageal transit. There was an association between dysphagia and abnormalities on manometry (P = 0.02) and between symptoms and scintigraphy data (P = 0.01). Dysphagia in caustic strictures is due to esophageal motility abnormalities, which are closely related to the scarred segment.

Effect of topically applied Na-hyaluronan on experimental corneal alkali wound healing

The effect of topically applied 1% sodium hyaluronate (Na-HA) on the healing of a standardized corneal alkali wound was studied. The healing of the epithelium, stroma, and endothelium was evaluated separately, using quantitative methods. Central corneal alkali wound was produced in one eye of the rabbits by applying a 5.5-mm round filter paper, soaked in 1 N NaOH, for 60 seconds. 1% Na-HA in the treatment group and phosphate buffered saline (PBS) in the control group were given topically 4 times per day for 2 days, 1- and 3-weeks. Epithelial and endothelial healing was assessed morphometrically from standardized photographs and micrographs, respectively. Stromal healing was determined by counting polymorphonuclear leukocytes (PMN) and keratocytes in the central and marginal wound areas. A positive healing influence was observed in the epithelium. In stromal healing, 1% Na-HA treated corneas showed less PMNs and more keratocytes than the control group, suggesting that topically applied 1% Na-HA may suppress the stromal PMN infiltration and enhance the keratocyte repopulation during corneal alkali wound healing. However, no significant difference was found in morphometric evaluation of endothelial healing between the two groups.

Riscos químicos e toxicológicos de algumas substâncias utilizadas em laboratórios / Chemical and toxicological risks of some substances used in the laboratory

A segurança em laboratório se fundamenta no conhecimento das caracteristícas físico-químicas, na toxicocinética e/ou principais açöes e efeitos tóxicos das substâncias mais comumente utilizadas, como diversos solventes orgânicos, o ácido sulfúrico, a amônia e o hidróxido de sódio. É importante também, conhecer-se quais säo os riscos e os cuidados que se deve tomar no armazenamento e manuseio destes materiais e as medidas de primeiros socorros nos casos de exposiçäo excessiva.