Continuous stirring is essential to prevent stratification of slowly reacting, mutually insoluble, liquids. With octanol and diborane: Addition of sodium hydroxide solution during work-up of a reaction mixture of oxime and diborane in tetrahydrofuran is very exothermic, a mild explosion being noted on one occasion.
With zinc: Accidental contamination of a metal scoop with flake sodium hydroxide, prior to its use with zinc dust, caused ignition of the latter. With zinc and 4-methylnitrophenol: In preparation of 2,2-dimethoxyazoxybenzene, solvent ethanol was distilled out of the mixture of o-nitroanisole, zinc and sodium hydroxide, before reaction was complete. The exothermic reaction continued unmoderated, and finally exploded.
This was confirmed in laboratory experiments. Chlorohydroxyacetylene, the isomeric chloroketene or chlorooxirene, may have been formed by elimination of hydrogen chloride. National Institute for Occupational Safety and Health. Washington, D. Government Printing Office, Sax's Dangerous Properties of Industrial Materials 9th ed.
Lewis, R. Sax's Dangerous Properties of Industrial Materials. Volumes Under the proper conditions of temperature, pressure, and state of division, it can ignite or react violently with Report to the base station and the receiving medical facility the condition of the patient, treatment given, and estimated time of arrival at the medical facility.
If a chemical has been ingested, prepare the ambulance in case the victim vomits toxic material. Have ready several towels and open plastic bags to quickly clean up and isolate vomitus. Consult with the base station physician or the regional poison control center for advice regarding triage of multiple victims.
Patients with evidence of ingestion or substantial inhalation exposure or who have evidence of eye or skin burns should be transported to a medical facility for evaluation. Others may be discharged from the scene after their names, addresses, and telephone numbers are recorded. Those discharged should be advised to seek medical care promptly if symptoms develop see Patient Information Sheet below.
Unless previously decontaminated, all patients suspected of contact with solid sodium hydroxide or its solutions and all victims with skin or eye irritation require decontamination as described below.
Because sodium hydroxide is extremely corrosive, hospital personnel should don rubber gloves, rubber aprons, and eye protection before treating contaminated patients. All other patients may be transferred to the Critical Care area. Be aware that use of protective equipment by the provider may cause fear in children, resulting in decreased compliance with further management efforts.
Also, emergency room personnel should examine children's mouths because of the frequency of hand-to-mouth activity among children. Evaluate and support airway, breathing, and circulation. Children may be more vulnerable to corrosive agents than adults because of the smaller diameter of their airways.
Because of possible corrosive injury, intubation should be done carefully. If not possible, surgically create an airway. Patients who are comatose, hypotensive, or have seizures or ventricular arrhythmias should be treated in the conventional manner. Patients who are able may assist with their own decontamination. Remove contact lenses if easily removable without additional trauma to the eye. If a corrosive material is suspected or if pain or injury is evident, continue irrigation while transferring the victim to the Critical Care Area.
Victims who are conscious and able to swallow can be given 4 to 8 ounces of milk or water if this has not been given previously see Critical Care Area below for more information on ingestion exposure. Be certain that appropriate decontamination has been carried out see Decontamination Area above. Evaluate and support airway, breathing, and circulation as in ABC Reminders above. Establish intravenous access in seriously ill patients if this has not been done previously.
Continuously monitor cardiac rhythm. Patients who are comatose, hypotensive, or have seizures or cardiac arrhythmias should be treated in the conventional manner. Administer supplemental oxygen by mask to patients who have respiratory symptoms.
Skin burns from sodium hydroxide should be irrigated frequently with normal saline for 24 hours. Consider early within 1 hour of exposure institution of continuous hydrotherapy. Neutralizing substances should not be used. Fluid resuscitation should be provided as for comparable thermal burns; keeping in mind that the full extent of the sodium hydroxide burn may not be accurately assessed for 24 to 48 hours and may be underestimated initially.
Because of their relatively larger surface area:body weight ratio children are more vulnerable to toxicants affecting the skin. Continue eye irrigation until the pH of the conjunctival sac is neutral pH 7.
The pH of the conjunctiva should be checked every 30 minutes for 2 hours after irrigation is stopped to ensure that the measured pH is that of the tissue and not the irrigating fluid. Ensure that any particulate matter has been removed. A mydriatic-cycloplegic medication such as homatropine should be used to prevent synechiae.
Examine the eyes for conjunctival or corneal damage and treat appropriately. Immediately consult an ophthalmologist for patients who have eye exposure. Victims who are conscious and able to swallow can be given 4 to 8 ounces of milk or water if this has not been given previously.
Extreme throat swelling may require endotracheal intubation or cricothyroidotomy. Gastric lavage is useful in certain circumstances to remove caustic material and prepare for endoscopic examination. Consider gastric lavage with a small nasogastric tube if: 1 a large dose has been ingested; 2 the patient's condition is evaluated within 30 minutes; 3 the patient has oral lesions or persistent esophageal discomfort; and 4 the lavage can be administered within one hour of ingestion.
Placement of the gastric tube should be guided by endoscopy because blind gastric-tube placement may further injure the chemically damaged esophagus or stomach. Endoscopic evaluation is essential in cases of sodium hydroxide ingestion, and surgical consultation is recommended for patients who have suspected perforation.
Signs and symptoms do not provide an accurate guide to the extent of injury. All patients suspected of significant caustic ingestion must have early endoscopy to assess injury to the esophagus, stomach and duodenum, and to guide subsequent management. Severe esophageal burns have occurred even in cases where burns of the mouth or oropharynx were not seen. The ingestion of large amounts of sodium hydroxide may also result in shock. Endoscopy may be contraindicated in cases where the patient is unstable, has upper airway compromise, evidence of perforation, or ingestion took place more than 48 hours previously.
Because children do not ingest large amounts of corrosive materials, and because of the risk of perforation from NG intubation, lavage is discouraged in children unless performed under endoscopic guidance. Toxic vomitus or gastric washings should be isolated e.
There is no antidote for sodium hydroxide. Various treatments to decrease stricture formation have been proposed including administration of ascorbic acid and steroids , but are not recommended. The diagnosis of acute sodium hydroxide toxicity is primarily clinical, based on symptoms of corrosive injury. However, laboratory testing is useful for monitoring the patient and evaluating complications.
Routine laboratory studies for all exposed patients include CBC, glucose, and electrolyte determinations. You can buy electronic pH meters or pH indicator paper from any biological or lab supply company, which can be used to give you an accurate measurement of the acidic or basic quality of substances you want to test.
Try this simulation to determine the pH of some common substances. Optional Mini-Experiment : Make your own pH indicator using red cabbage juice. Blend 2 cups of chopped red cabbage leaves and 1 cup water in a food processor or electric blender until pieces are tiny and uniform. Strain off the solids and keep the liquid. If you don't have a blender, you can also chop the cabbage coarsely and boil it in water for about 5 minutes until the liquid is dark purple.
This purple liquid will change color according to the acidity or alkalinity of substances you want to test. Add about 10 drops of cabbage juice to approximately 1 tablespoon of a test substance.
What color does the cabbage juice turn in an acid like white vinegar? What color does the cabbage juice turn in a base such as a baking soda and water solution? Test the pH of various substances and develop a corresponding color-pH scale. What happens to the pH of a plain solution when acid is added to it? What happens to the pH of a buffer solution when acid is added to it? Learning objectiveS Define and differentiate the terms acid and base Define the terms pH, neutral, acidic, and basic or alkaline Define the term buffer, and compare the response of a regular solution with a buffer solution to the addition of acid or base.
Concepts, terms, and facts check Study Questions Write your answer in a sentence form do not answer using loose words 1. What is an acid? What is a base? Concepts, terms, and facts check Study Question Write your answer in a sentence form do not answer using loose words 1.
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