VASOPRESSIN INJECTION (vay-soe-press'in) Classifications: hormone; pituitary, antidiuretic hormone (adh); Therapeutic: adh replacement Pregnancy Category: C
|
Availability
20 pressor units/mL injection
Action
Polypeptide hormone extracted from animal posterior pituitaries. Possesses pressor and antidiuretic (ADH) properties, but
is relatively free of oxytocic properties. Produces concentrated urine by increasing tubular reabsorption of water (ADH activity),
thus reabsorbing up to 90% of water in the renal tubules.
Therapeutic Effect
Effective in reversing diuresis caused by diabetes insipidus.
Uses
Antidiuretic to treat diabetes insipidus, to dispel gas shadows in abdominal roentgenography, and as prevention and treatment
of postoperative abdominal distension. Also given to treat transient polyuria due to ADH deficiency (related to head injuries
or to neurosurgery).
Unlabeled Uses
Test for differential diagnosis of nephrogenic, psychogenic, and neurohypophyseal diabetes insipidus; test to elevate ability
of kidney to concentrate urine, and provocative test for pituitary release of corticotropin and growth hormone; emergency
and adjunct pressor agent in the control of massive GI hemorrhage (e.g., esophageal varices).
Contraindications
Chronic nephritis accompanied by nitrogen retention; ischemic heart disease, PVCs, advanced arteriosclerosis; pregnancy
(category C); during first stage of labor; lactation.
Cautious Use
Epilepsy; migraine; asthma; heart failure, angina pectoris; any state in which rapid addition to extracellular fluid may
be hazardous; vascular disease; preoperative and postoperative polyuric patients, kidney disease; goiter with cardiac complications;
older adult patients, children.
Route & Dosage
Diabetes Insipidus Adult: IM/SC 510 U aqueous solution 24 times/d (560 U/d) or 1.252.5 U in oil q23d Intranasal Apply to cotton pledget or intranasal spray Child: IM/SC 2.510 U aqueous solution 24 times/d
Abdominal Distention, Abdominal Radiographic Procedures Adult: IM/SC 5 U with 510 U q34h prn or 515 U 2 h and 30 min prior to procedure
GI Hemorrhage Adult: IV 0.20.4 U/min up to 0.9 U/min
|
Administration
Intramuscular/Subcutaneous
- Give 12 glasses of water with vasopressin to reduce adverse effects of tannate and improve therapeutic response.
- Do NOT administer vasopressin tannate via IV. Warm ampule to body temperature and shake vigorously to disperse active principle
before withdrawing drug for IM administration.
- The tannate injection is often painful, and allergic reactions may develop. It is preferred for use in chronic therapy because
of its longer duration of action.
Intravenous PREPARE: Direct/IV Infusion: Dilute with NS or D5W to a concentration of 0.11 U/mL.
ADMINISTER: Direct: Give rapid bolus dose. IV Infusion: Titrate dose and rate to patient's response. ??Ensure patency prior to injection or infusion as extravasation may cause severe vasoconstriction with tissue necrosis and
gangrene.
|
Adverse Effects (≥1%)
Skin: Rash, urticaria.
Body as a Whole: Anaphylaxis;
tremor, sweating, bronchoconstriction,
circumoral and facial pallor, angioneurotic edema,
pounding in head, water intoxication (especially with tannate), gangrene at injection site with intraarterial infusion.
GI: Eructations, passage of gas, nausea, vomiting, heartburn, abdominal cramps, increased bowel movements secondary to excessive use.
CV: Angina (in patient with coronary vascular disease);
cardiac arrest, hypertension, bradycardia, minor arrhythmias, premature atrial contraction, heart block, peripheral vascular collapse,
coronary insufficiency,
MI; cardiac arrhythmia,
pulmonary edema, bradycardia (with intraarterial infusion).
Urogenital: Uterine cramps.
Respiratory: Congestion, rhinorrhea, irritation, mucosal ulceration and pruritus, postnasal drip.
Special Senses: Conjunctivitis.
Diagnostic Test Interference
Vasopressin increases plasma cortisol levels.
Interactions
Drug: Alcohol, demeclocycline, epinephrine, heparin, lithium, phenytoin may decrease antidiuretic effects of vasopressin;
guanethidine, neostigmine increase vasopressor actions;
chlorpropamide, clofibrate, carbamazepine, thiazide diuretics may increase antidiuretic activity.
Pharmacokinetics
Duration: 28 h in aqueous solution, 4872 h in oil, 3060 min
IV infusion.
Distribution: Extracellular fluid.
Metabolism: In liver and kidneys.
Elimination: In urine.
Half-Life: 1020 min.
Nursing Implications
Assessment & Drug Effects
- Monitor infants and children closely. They are more susceptible to volume disturbances (such as sudden reversal of polyuria)
than adults.
- Establish baseline data of BP, weight, I&O pattern and ratio. Monitor BP and weight throughout therapy. (Dose used to stimulate
diuresis has little effect on BP.) Report sudden changes in pattern to physician.
- Be alert to the fact that even small doses of vasopressin may precipitate MI or coronary insufficiency, especially in older
adult patients. Keep emergency equipment and drugs (antiarrhythmics) readily available.
- Check patient's alertness and orientation frequently during therapy. Lethargy and confusion associated with headache may
signal onset of water intoxication, which, although insidious in rate of development, can lead to convulsions and terminal
coma.
- Monitor urine output, specific gravity, and serum osmolality while patient is hospitalized.
- Withhold vasopressin, restrict fluid intake, and notify physician if urine-specific gravity is <1.015.
Patient & Family Education
- Be prepared for possibility of anginal attack and have coronary vasodilator available (e.g., nitroglycerin) if there is
a history of coronary artery disease. Report to physician.
- Measure and record data related to polydipsia and polyuria. Learn how to determine specific gravity and how to keep an accurate
record of output. Understand that treatment should diminish intense thirst and restore undisturbed normal sleep.
- Avoid concentrated fluids (e.g., undiluted syrups), since these increase urine volume.