Hypaque Sodium (Injection, Solution)
INTRAVENOUS DOSAGE: Adults. A dose of 30 mL of the 50 percent solution administered intravenously with or without compression produces diagnostic shadows in the majority of adults subjected to partial dehydration and to effective purgation. If the administration of 30 mL does not provide satisfactory visualization, this dose may be repeated in 15 to 30 minutes. In persons of slight build 20 mL may produce adequate shadows. Larger doses ranging from 50 mL to 60 mL of the 50 percent solution may be used for routine excretory urography in adults. The increased dosage offers better and more complete visualization of the urinary tract. This technique requires neither compression nor dehydration and is more effective in obese patients. Adverse reactions to the larger dose are similar to those encountered with lower doses without an increase in incidence, severity, or type of reactions. Voiding cystourethrograms may be obtained when desired. For the best results and minimal side effects, it is advisable to inject the total amount of solution intravenously in one to three minutes. Children. The dosage of the 50 percent solution for children under 6 months of age is 5 mL; for children 6 to 12 months of age, 6 mL to 8 mL; for children 1 to 2 years of age, 8 mL to 10 mL; for children 2 to 5 years of age, 10 mL to 12 mL; for children 5 to 7 years of age, 12 mL to 15 mL; for children 7 to 11 years of age, 15 mL to 18 mL, and for children 11 to 15 years ofage, 18 mL to 20mL.<br/>Subcutaneous or Intramuscular Urography: HYPAQUE sodium 50 percent may be used for excretory urography via intramuscular injection, undiluted or diluted; or subcutaneously diluted with equal quantities of sterile water for injection. The intramuscular injection site generally used is the gluteal muscles in two separate, equal doses. Used subcutaneously the medium is generally injected in divided equal doses over each scapula. In both locations the contrast medium is rapidly absorbed providing urograms beginning variously 5 to 10 minutes following intramuscular injection; subsequent exposures being made according to degree of pyelographic contrast. Radiographs with subcutaneous injection are usually exposed at 10, 20, and 30 minutes. The urograms achieved with either methods will be almost equal to that following intravenous injection. The usual intramuscular or subcutaneous (diluted) dose of HYPAQUE sodium 50 percent in adults and older children is about 20 mL to 30 mL. For infants and young children, the dose ranges from 5 mL to 16 mL.<br/>Roentgenography: A plain film is often made prior to IVP. A nephrogram effect is available in 30 to 60 seconds. Its duration is dose dependent. Urograms may be available as early as two minutes.However, urograms of optimal density are usually made at 5, 10, or 15 minutes following injection. Ureteric films are usually made between 10 and 20 minutes, and cystograms at 30 minutes. In impaired renal function, delayed films may be required.
HYPAQUE sodium, brand of diatrizoate sodium, is a radiopaque diagnostic agent, water-soluble organic iodide contrast medium. In pure form, it contains 59.87 percent organically bound iodine. The 50 percent (w/v) solution contains 300 mg iodine per mL and 0.8 mEq (18.1 mg) sodium per mL. It has an osmolality of 1515 mosm/kg (determined by VPO), and is hypertonic to blood. As a point of information only, a 10 percent solution (w/v) is isotonic. The viscosity (cp) is about 3.25 at 25��C and 2.34 at 37��C. Sodium carbonate and hydrochloric acid have been added to adjust pH between 6.5 and 7.7.The pKa is 3.4 for diatrizoic acid. If a solution of this medium is chilled, crystals may form but readily dissolve if the vial is placed in moderately hot water before use; cool to body temperature before injecting. The sterile aqueous solution is clear and nearly colorless. It is relatively thermostable and may be autoclaved without harmful effects, although it should be protected from strong light. The 50 percent solution contains edetate calcium disodium 1:10,000 as a sequestering stabilizing agent. Diatrizoate sodium is a triiodinated benzoic acid derivative, the sodium salt of 3,5-diacetamido-2,4,6-triiodobenzoate with a molecular weight of 635.90, and has the following structural formula:
Intravascular injection of a radiopaque diagnostic agent opacifies those vessels in the path of the flow of the contrast medium, permitting radiographic visualization of the internal structures of the human body until significant hemodilution occurs. At physiologic pH, the water-soluble contrast media are completely dissociated into a radiopaque anion and a solubilizing cation. While circulating in tissue fluids, the compound remains ionized. However, it is not metabolized but excreted unchanged in the urine, each diatrizoate molecule remaining "obligated" to its sodium moiety. Following intravenous injection, the radiopaque diagnostic agents are immediately diluted in the circulating plasma. Equilibrium is reached with the extracellular compartment at about 10 minutes. Hence, the plasma concentration at 10 minutes is closely related to the dose corrected to body size. The pharmacokinetics of the intravenously administered radiopaque contrast media are usually best described by a two compartment model with a rapid alpha phase for drug distribution and a slow beta phase for drug elimination. In patients with normal renal function, the alpha and beta half-lives were respectively 30 minutes and 120 minutes for diatrizoate. But in patients with renal functional impairment, the elimination half-life for the beta phase can be prolonged up to several days. Injectable radiopaque diagnostic agents are excreted either through the liver or through the kidneys. These two excretory pathways are not mutually exclusive, but the main route of excretion seems to be governed by the affinity of the contrast medium for serum albumin. From 0% to 10% of diatrizoate sodium is bound to serum protein. Diatrizoate salts are excreted unchanged predominantly through the kidneys by glomerular filtration. The amount excreted by the kidney during any period of time is determined by the filtered load; ie, the product of plasma contrast media concentration and glomerular filtration rate. The plasma concentration is dependent upon the dose administered and the body size. The glomerular filtration rate varies with the body size, sex, age, circulatory dynamics, diuretic effect of the drug, and renal function. In patients with normal renal function the maximum urinary concentration of diatrizoate sodium occurs within 10 minutes with 12 percent ofthe administered dose being excreted. The mean values of cumulative urinary excretion for diatrizoate sodium expressed as percentage of administered dose are 38 percent at 60 minutes, 45 percent at 3 hours, and 94 to 100 percent at 24 hours. Urinary excretion of contrast media is delayed in infants younger than 1 month and in patients with urinary tract obstruction. The urinary iodine concentration is higher with the sodium salt of diatrizoic acid than with the meglumine salt. The liver and small intestine provide the major alternate route of excretion for diatrizoate. In patients free of severe renal disease, the fecal recovery is less than 2 percent of the administered dose. In patients with severe renal impairment the excretion of these contrast media through the gallbladder and into the small intestine sharply increases; up to 20 percent of the administered dose has been recovered in the feces in 48 hours. Saliva is a minor secretory pathway for injectable radiopaque diagnostic agents. In patients with normal renal function, minimal amounts of contrast media are secreted unchanged. However, in uremic patients small amounts of free iodides resulting from deiodination prior to administration or in vivo, have been detected in the saliva. Diatrizoate salts cross the placental barrier in humans by simple diffusion and appear to enter fetal tissue passively. No apparent harm to the fetus was observed when diatrizoate sodium and diatrizoate meglumine were injected intravenously 24 hours prior to delivery. However, abnormal neonatal opacification of the small intestine and colon were detected 4 to 6 days after delivery. Procedures including radiation involve a certain risk related to the exposure of the fetus. Injectable radiopaque diagnostic agents are excreted unchanged in human milk.<br/>Computerized Tomography: HYPAQUE sodium 50 percent can be administered as an intravenous bolus for brain tissue enhancement using computerized tomography. Increased tissue contrast differential for the scan is achieved either because of increased vascular (arterial, venous, or capillary bed) contrast or by blood brain barrier penetration of the medium (or its absence) in certain localized areas of disrupted vascular permeability. The degree of tissue enhancement caused by increased blood contrast is directly related to blood iodine content. However, the degree of enhancement due to extravascular accumulation of iodine resulting from blood brain barrier disruption will depend on the extent of disruption, the blood level of iodine, and the time delay prior to scanning. The nature of the pathology will determine whether an immediate or delayed scan is optimal.<br/>Effects of Steroid Therapy: The anti-inflammatory and antiedema effects in patients receiving steroid therapy have interfered with the expected distribution of CT tissue enhancement on the scan in certain diseases.
Percutaneous transhepatic cholangiography is contraindicated in patients with coagulation defects and prolonged prothrombin times until normal, or near normal, coagulation is achieved, eg, with vitamin K.
Vials of 50 mL, rubber stoppered, box of 25 (NDC 0407-0766-04). Protect from light. Store at 15��C to 30��C (59��F to 86��F).
See PRECAUTIONS���General. Some clinicians consider multiple myeloma a contraindication to excretory urography because of the great possibility of producing transient to fatal renal failure. Others believe that the risk of causing anuria is definite but small. If excretory urography is performed in the presence of multiple myeloma, dehydration should be avoided since it favors protein precipitation in renal tubules. Although azotemia is not considered a contraindication, care is required in patients with advanced renal failure. The usual preparatory dehydration should be omitted, and urinary output should be observed for one to two days in these patients. Adequate visualization may be difficult or impossible to attain in patients with severely impaired renal and/or hepatic function. Use with extreme caution in patients with concomitant hepatorenal disease.<br/>Preparatory Dehydration: Preparatory dehydration is dangerous in infants, young children, the elderly, and azotemic patients (especially those with polyuria, oliguria, diabetes, advanced vascular disease, or preexisting dehydration). The undesirable dehydration in these patients may be accentuated by the osmotic diuretic action of the medium. Dehydration may improve image quality in patients with adequate renal function particularly if a low dose is used. Dehydration, however, will not improve contrast quality in patients with substantial renal insufficiencies and will increase risk of contrast induced renal damage. Dehydration in these patients is therefore contraindicated.
At dosage levels of diatrizoate sodium above a level containing 45 g of iodine, the incidence of unpleasant side effects increases. At total dosage equivalent to 80 gI or 90 gI administered over a short period of time (eg, 30 minutes), clinical signs of systemic intolerance appear (mostly related to hyperosmolar effects) and are manifest as tremors, irritability, and tachycardia. Above these maximal tolerated dosage levels in otherwise healthy adults, an increasing incidence and severity of dyspnea and pulmonary edema should be expected. Four cases of overdosage in infants, during urography, are reported. Three of the infants died within 19 hours of the injection. The overdose ranged from slightly above the recommended pediatric dosage to a dose exceeding 19 g/kg. The symptoms of overdosage appeared between 10 minutes to several hours after injection of the contrast medium. Adverse effects were life-threatening, affecting mainly the pulmonary and cardiovascular systems. The symptoms included: cyanosis, bradycardia, acidosis, pulmonary hemorrhage, convulsions, coma, and cardiac arrest. All infants showed a poor visualization of the kidneys and a diffuse opacification of all the tissues and vasculature. Autopsy findings showed acute pulmonary damage and/or edema of subcutaneous tissues. Treatment of an overdose of injectable radiopaque contrast media is directed toward the support of all vital functions, and prompt institution of symptomatic therapy. The acute intravenous LD50 of diatrizoate sodium in mice is equivalent in iodine content of 5.3 gI/kg to 8.0 gI/kg and seem to be directly proportional to the rate of injection. Diatrizoate sodium is dialyzable.
Hypaque Sodium (Injection, Solution)
See ADVERSE REACTIONS���General.
Pheochromocytoma. Administration of angiographic media to patients known or suspected to have pheochromocytoma can cause dangerous changes in blood pressure. A minimum dose should be injected. The blood pressure should be carefully monitored and measures for controlling major fluctuations should be available. During aortography by the translumbar technique, extreme care is advised to avoid inadvertent intrathecal injection since the injection of even small amounts (5 mL to 7 mL) of the contrast medium may cause convulsions, permanent sequelae, or fatality. Should the accident occur, the patient should be placed upright to confine the hyperbaric solution to a low level, anesthesia may be required to control convulsions, and if there is evidence of a large dose having been administered, a careful cerebrospinal fluid exchange-washout should be considered.
HYPAQUE sodium 50 percent is indicated for excretory urography, cerebral and peripheral angiography, aortography, intraosseous venography, direct cholangiography, hysterosalpingography, splenoportography, and contrast enhancement of computed tomographic head imaging.<br/>UROGRAPHY: Diatrizoate salts are used in small, medium, and large dose urography . Visualization of the urinary tract can be achieved by either direct intravenous bolus injection, intravenous drip infusion, or incidentally following intra-arterial procedures.Visualization of the urinary tract is delayed in infants less than 1 month old, and in patients with urinary tract obstruction .<br/>CONTRAST ENHANCEMENT OF COMPUTED TOMOGRAPHIC HEAD IMAGING: Injectable radiopaque contrast media may be used to refine diagnostic precision in areas of the brain which may not otherwise have been satisfactorily visualized.<br/>Tumors: Radiopaque diagnostic agents may be useful to investigate the presence and extent of certain malignancies such as: gliomas including malignant gliomas, glioblastomas, astrocytomas, oligodendrogliomas and gangliomas, ependymomas, medulloblastomas, meningiomas, neuromas, pinealomas, pituitary adenomas, craniopharyngiomas, germinomas, and metastatic lesions. The usefulness of contrast enhancement for the investigation of the retrobulbar space and in cases of low grade or infiltrative glioma has not been demonstrated. In calcified lesions, there is less likelihood of enhancement. Following therapy, tumors may show decreased or no enhancement. The opacification of the inferior vermis following contrast media administration has resulted in false-positive diagnosis in a number of normal studies.<br/>Nonneoplastic Conditions: The use of injectable radiopaque diagnostic agents may be beneficial in the image enhancement of nonneoplastic lesions. Cerebral infarctions of recent onset may be better visualized with contrast enhancement, while some infarctions are obscured if contrast media are used. The use of iodinated contrast media results in contrast enhancement in about 60 percent of cerebral infarctions studied from one to four weeks from the onset of symptoms. Sites of active infection may also be enhanced following contrast media administration. Arteriovenous malformations and aneurysms will show contrast enhancement. For these vascular lesions, the enhancement is probably dependent on the iodine content of the circulating blood pool. Hematomas and intraparenchymal bleeders seldom demonstrate any contrast enhancement. However, in cases of intraparenchymal clot, for which there is no obvious clinical explanation, contrast media administration may be helpful in ruling out the possibility of associated arteriovenous malformation.<br/>ANGIOGRAPHY: Diatrizoate salts are used for radiographic studies throughout the cardiovascular system. Intravascular radiopaque diagnostic agents of high concentration are not recommended for cerebral or spinal angiography , and contrast agents with the lowest compatible viscosity and higher concentration of iodine (310 mg/mL to 480 mg/mL of bound iodine) must be used for angiocardiography. Contrast media approaching serum ionic content and osmolality have less potential for deleterious effects on the myocardium . Addition of chelating agents may contribute to toxicity in coronary angiography, and the sodium content of angiographic agents used in coronary arteriography is of crucial importance. In addition to the following general CONTRAINDICATIONS, WARNINGS, PRECAUTIONS, and ADVERSE REACTIONS, there are additional listings in these categories under the particular procedures.