Norfine Special Precautions

Caution is advised in patients with major left ventricular dysfunction associated with acute hypotension. Supportive therapy should be initiated simultaneously with diagnostic evaluation. Norepinephrine should be reserved for patients with cardiogenic shock and refractory hypotension, in particular those without elevated systemic vascular resistance.
Occurrence of heart rhythm disorders during the treatment must lead to a reduction in the dosage.
Cardiac arrhythmias may arise when Norepinephrine is used in conjunction with cardiac sensitizing agents, and may be more likely in patients with hypoxia or hypercarbia.
Particular caution should be observed in patients with coronary, mesenteric or peripheral vascular thrombosis because Norepinephrine may increase the ischemia and extend the area of infarction, unless in the opinion of the attending physician, the administration of Norepinephrine is necessary as a life-saving procedure. Similar caution should be observed in patients with hypotension following myocardial infarction and in patients with angina, particularly Prinzmetal's variant angina, diabetes, hypertension or hyperthyroidism.
Special caution should be used for patients with liver failure, severe renal dysfunction, ischemic heart diseases and elevated intracranial pressure. Overdoses or conventional doses in hypersensitive persons (e.g. hyperthyroid patients) may cause severe hypertension with violent headache, photophobia, stabbing retrosternal pain, pallor, intense sweating and vomiting. Hypertension may eventually lead to acute pulmonary oedema, arrhythmia or cardiac arrest.
Care should be taken in diabetics as it increases the level of blood glucose (due to the glycogenolytic action in the liver and the inhibition of insulin release from the pancreas).
The elderly may be especially sensitive to the effects of Norepinephrine due to the greater frequency of hepatic, renal or cardiac dysfunction and concomitant disease or other drug therapy.
The use of Norepinephrine in children is not recommended.
Norepinephrine should only be used by doctors familiar with the selective indications for its use.
Where indicated, appropriate replacement therapy of blood or fluid together with adoption of the supine position with elevation of the legs, must be instituted and maintained prior to and/or during therapy with this product. When infusing Norepinephrine, the blood pressure and rate of flow should be checked frequently to avoid hypertension. Therefore, it is desirable to record the blood pressure every two minutes from the time the administration started until the desired blood pressure is obtained and then every five minutes thereafter, if the administration is to be continued. The rate of flow must be watched constantly and the patient should never be left unattended while receiving Norepinephrine. Hypertension may eventually lead to acute pulmonary oedema, arrhythmia or cardiac arrest.
The infusion of Norepinephrine should be stopped gradually as sudden cessation may produce a catastrophic fall in blood pressure.
Extravasation: The infusion site should be checked frequently for free flow. Care should be taken to avoid extravasation of Norepinephrine into the tissues, as local necrosis might ensue due to the vasoconstrictive action of the drug. Blanching along the course of the infused vein, sometimes without obvious extravasation, has been attributed to vasa vasorum constriction with increased permeability of the vein wall, permitting some leakage. On rare occasions this may progress to superficial slough, particularly during infusion into leg veins in elderly patients or in those suffering from obliterative vascular disease. If blanching occurs, consideration should be given to changing the infusion site at intervals to allow the effects of local vasoconstriction to subside.
IMPORTANT: Antidote for Extravasation Ischaemia: To prevent sloughing and necrosis in areas in which extravasation has taken place, the area should be infiltrated as soon as possible with 10 mL to 15 mL of saline solution containing from 5 mg to 10 mg of phentolamine, an adrenergic blocking agent. A syringe with a fine hypodermic needle should be used with the solution being infiltrated liberally throughout the area, which is easily identified by its cold, hard and pallid appearance. Sympathetic blockade with phentolamine causes immediate and conspicuous local hyperaemic changes if the area is infiltrated within 12 hours. Phentolamine should be given as soon as possible after the extravasation is noted and infusion should be stopped.
Effects on Ability to Drive and Use of Machines: No information is available.