Tranexamic Acid

Brand name: Hemostan, Fibrinon, Cyklokapron, Lysteda, Transamin

Classification: Anti-fibrinolytic, antihemorrhagic

Indications:

Tranexamic acid is used for the prompt and effective control of hemorrhage in various surgical and clinical areas:

• Treating heavy menstrual bleeding
• Hemorrhage following dental and/or oral surgery in patients with hemophilia
• Management of hemophilic patients (those having Factor VIII or Factor IX deficiency) who have oral mucosal bleeding, or are undergoing tooth extraction or other oral surgical procedures^.
• Surgical: General surgical cases but most especially operative procedures on the prostate, uterus, thyroid, lungs, heart, ovaries, adrenals, kidneys, brain, tonsils, lymph nodes and soft tissues.
• Obstetrical and gynecological: abortion, post-partum hemorrhage and menometrorrahgia
• Medical: epistaxis, hemoptysis, hematuria, peptic ulcer with hemorrhage and blood dyscrasias with hemorrhage
• Effective in promoting hemostasis in traumatic injuries.
• Preventing hemorrhage after orthopedic surgeries.

Mechanism of Action

Tranexamic acid is a synthetic derivative of the amino acid lysine. It exerts its antifibrinolytic effect through the reversible blockade of lysine-binding sites on plasminogen molecules. Anti-fibrinolytic drug inhibits endometrial plasminogen activator and thus prevents fibrinolysis and the breakdown of blood clots. The plasminogen-plasmin enzyme system is known to cause coagulation defects through lytic activity on fibrinogen, fibrin and other clotting factors. By inhibiting the action of plasmin (finronolysin) the anti-fibrinolytic agents reduce excessive breakdown of fibrin and effect physiological hemostasis.

Contraindications

1. Allergic reaction to the drug or hypersensitivity
2. Presence of blood clots (eg, in the leg, lung, eye, brain), have a history of blood clots, or are at risk for blood clots
3. Current administration of factor IX complex concentrates or anti-inhibitor coagulant concentrates

Precautions

1. Pregnancy. Tranexamic acid crosses the placenta.
2. Lactation. Tranexamic acid is distributed into breast milk; concentrations reach approximately 1% of the maternal plasma concentration.
3. Contraceptives, estrogen-containing, oral or Estrogens. Concurrent use with tranexamic acid may increase the potential for thrombus formation.
4. Renal function impairment    (medication may accumulate; dosage adjustment based on the degree of impairment is recommended)
5. Hematuria of upper urinary tract origin    (risk of intrarenal obstruction secondary to clot retention in the renal pelvis and ureters if hematuria is massive; also, if hematuria is associated with a disease of the renal parenchyma, intravascular precipitation of fibrin may occur and exacerbate the disease)

Nursing Responsibilities

1. Unusual change in bleeding pattern should be immediately reported to the physician.
2. For women who are taking Tranexamic acid to control heavy bleeding, the medication should only be taken during the menstrual period.
3. Tranexamic Acid should be used with extreme caution in CHILDREN younger than 18 years old; safety and effectiveness in these children have not been confirmed.
4. The medication can be taken with or without meals.
5. Swallow Tranexamic Acid whole with plenty of liquids. Do not break, crush, or chew before swallowing.
6. If you miss a dose of Tranexamic Acid, take it when you remember, then take your next dose at least 6 hours later. Do not take 2 doses at once.
7. Inform the client that he/she should inform the physician immediately if the following severe side effects occur:

• Severe allergic reactions such as rash, hives, itching, dyspnea, tightness in the chest, swelling of the mouth, face, lips or tongue
• Calf pain, swelling or tenderness
• Chest pain
• Confusion
• Coughing up blood
• Decreased urination
• Severe or persistent headache
• Severe or persistent body malaise
• Shortness of breath
• Slurred speech
• Slurred speech
• Vision changes

image courtesy of openrussia.ru

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Lidocaine

Brand Name: (Parenteral) LidoPen, Xylocaine (Local Anesthetic) Dilocane, Lidoject, Nervocaine, Octocaine, Xylovaine (Mucosal) Anestacon, Xylocaine Viscous (Lidocaine Patch) Lidoderm, (Topical) DermaFlex, ELA-Max, Solarcaine, Aloe Extra Burn Relief, Xylocaine, Zilactin-L

Classification: Anesthetic – topical or local, Antiarrythmics

Indications:

• Intravenous – ventricular arrhythmias
• Intramuscular – self-injected or when IV is unavailable during transport to local facilities
• Local – infiltration or mucosal or topical anesthetic
• Patch – used when pain is present due to post-herpetic neuralgia

Mechanism of action

When administered intramuscularly or intravenously, Lidocaine suppresses the automaticity and spontaneous depolarization of the ventricles during diastole by altering the flux of sodium ions across the cell membrane with little or no effect on the heart. Locally, it produces local anesthesia effect by inhibiting the transport of ions across the neural membranes. Thus, initiation and conduction of normal nerve impulses is prevented.

Contraindications

• Hypersensitivity
• Advanced AV block

Used cautiously in patients with:

• Liver diseases
• Congenital heart failure
• Patient weighing less than 50 kilograms
• Geriatric patients
• Respiratory depression
• Shock
• Heart block
• Pregnancy and lactation

Adverse reactions

• Drowsiness
• Dizziness
• Nervousness
• (mucosal use) decreased or absent gag reflex
• Bradycardia
• Hypotension
• Burning sensation

Signs and symptoms of toxicity and overdose of Lidocaine:

• Confusion
• Excitation
• Blurred or double vision
• Nausea and vomiting
• Ringing in the ears
• Tremors
• Twitching
• Seizures
• Difficulty breathing
• Severe dizziness and fainting
• Unusually low heart rate

Nursing Responsibilities

• When Lidocaine is administered as an antiarrhythmic the nurse should monitor the ECG continuously. Blood pressure and respiratory status should be monitored frequently during the drug administration.
• When administered as an anesthetic, the numbness of the affected part should be assessed.
• Serum Lidocaine levels should be monitored frequently during prolonged use. Therapeutic serum lidocaine levels range from 1.5 to 5 mcg/ml.
• If signs of overdose occur (listed above), stop the infusion immediately and monitor the patient closely.
• For throat sprays, make sure that the patient’s gag reflex is intact before allowing the patient to eat or drink.
• When IM injections are used, the medication should be administered in the deltoid muscle only while frequently aspirating to prevent IV injection.
• For direct IV injection only 1% and 2% solutions are used.
• Undiluted IV loading dose of Lidocaine is administered at 1 mg/kg at a rate of 25 to 50 mg over 1 minute. The dose may be repeated after 5 minutes.

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Acetazolamide

Generic Name: Acetazolamide

Brand Name: Diamox, Dazamide, Diamox Sequels, Storzolamide, Acetazolam, Apo-Acetazolamide

Pharmacologic Classification: Carbonic Anhydrase Inhibitor

Therapeutic Classification: antiglaucoma, diuretics, ocular hypotensive agents, anticonvulsants

Indications

• Glaucoma (lowers intraocular pressure in the treatment of glaucoma)
• Epilepsy
• Congestive heart failure
• Drug-induced edema
• Altitude sickness (mountain sickness)

Mechanisms of Action

Acetazolamide is an enzyme inhibitor that acts particularly on carbonic anhydrase. Carbonic anhydrase is the enzyme that converts carbon dioxide and water to carbonic acid (H2CO3). Carbonic anhydrase inhibitors, such as Acetazolamide inhibits carbonic anhydrase in the tissues and fluid thus, decreasing carbonic acid in the body.

In the eye, the inhibitory action of Acetazolamide decreases the secretion of aqueous humor that lowers the intraocular pressure which is desirable in glaucoma. In the central nervous system (CNS), restrained carbonic anhydrase retards the abnormal and paroxysmal excessive discharge from the neurons of CNS.

In the kidneys, carbonic acid is excreted due to the inhibited carbonic anhydrase function. The result is renal loss of bicarbonate which carries out sodium, potassium and water. Alkalinization of urine and diuresis then takes place.

Contraindications

• Hypersensitivity to carbonic anhydrase inhibitor
• Hypersensitivity to sulfonamides
• Depressed levels of serum potassium and sodium
• Marked kidney and liver disease
• Suprarenal grand failure
• Hyperchloremic disease
• First trimester of pregnancy
• Concurrent use of ophthalmic carbonic anhydrase inhibitors (brinzolamide, dorzolamide)
• Adrenal gland failure (Addison’s disease)
• Sickle cell anemia
• Chronic non-congestive glaucoma

Use cautiously in

• Chronic respiratory disease
• Diabetes Mellitus
• Second or third trimester of pregnancy
• Lactation
• History of kidney stones

Adverse Reactions and Side Effects

• Depression
• Tiredness
• Body malaise
• Drowsiness and confusion
• Transient nearsightedness
• Anorexia
• Metallic taste
• Nausea and vomiting
• Crystalluria
• Renal calculi
• Rashes
• Hyperglycemia
• Hyperchloremic acidosis
• Hypokalemia
• Aplastic anemia
• Hemolytic anemia
• Leucopenia
• Weight loss
• Paresthesias
• Tingling feeling of the extremities
• Polyuria
• Polydipsia
• Blushing
• Headache
• Irritability
• Photosensitivity (rare)

Occasional adverse reactions:

• Urticaria
• Melena
• Hematuria
• Glycosuria
• Hepatic insufficiency
• Flaccid paralysis

During long-term therapy, an acidotic state may occasionally appear. This can managed or corrected by the administration of bicarbonate.

Dosage and Route

PO (adults)

Glaucoma: 250-1000 mg/day in 1-4 divided doses (up to 250 mg every 4 hours)

Epilepsy: 4-30 mg/kg/day in 1-4 divided doses

Altitude sickness: 250 mg 2-4 times a day started 24-48 hours before ascent, continued for 48 hours or longer to control symptoms.

PO (Children)

Glaucoma: 8-30 mg/kg/day in 3 divided doses

IM, IV (Adults): 250-500 mg, may repeat in 2-4 hours

IM, IV (children): 5-10 mg/kg every 6 hours

Nursing Management

1. 1. Monitor individuals taking acetazolamide with primidone and carbamazepine.  Acetazolamide may increase the blood levels of carbamazepine and quinidine and may decrease the blood levels of primidone.
2. Instruct the patient to avoid taking aspirin with Acetazolamide. Increase in side effects such as drowsiness, confusion, lethargy, hyperventilation and ringing in the ears when acetazolamide is taken with aspirin.
3. Monitor electrolyte levels.

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Methotrexate

Methotrexate

Brand Name: Amethoptertin, Folex, Trexall

Classification: Antineoplastic, antirheumatic, immunosuppressant, antimetabolite

Indications

• Trophoblastic neoplasms (choriocarcinoma, Hydatidiform Mole)
• Leukemia
• Breast, head and neck carcinoma
• Severe psoriasis and rheumatoid arthritis unresponsive to conventional therapy
• Ectopic pregnancy
• Lymphosarcoma
• Mycosis fungoides
  

  Methotrexate Pill

Action

Methotrexate works against folic acid metabolism which leads to the inhibition of DNA synthesis and cell production. The drug’s principal mechanism is through competitive inhibition of the enzyme folic acid reductase. For the cells to proliferate and replicate, folic acid must be reduced to tetrahydrofolic acid by this enzyme (folic acid reductase) in the process of DNA synthesis and cellular replication. With the administration of Methotrexate, the reduction of folic acid to tetrahydrofolic acid is inhibited thus, interfering with the tissue cell reproduction.

Because of this function, death of rapidly replicating cells (e.g. cancer cells, choriocarcinoma, leukemia, carcinoma in different body parts and ectopic pregnancy) specifically the malignant ones is made possible. It also has an immunosuppressive activity.

Contraindications

• Known allergic hypersensitivity to the drug
• Pregnancy

Methotrexate has caused fetal death and/or congenital anomalies, therefore, it is not recommended in women of childbearing potential unless there is imperative medical evidence that the benefits can be expected to outweigh the considered risks. Pregnant psoriatic patients should not receive this drug.

• Concomitant use of other drugs that has a hepatotoxic potential (including alcohol) should be avoided.

Adverse Reactions

1. Dizziness
2. Drowsiness
3. Headaches
4. Malaise
5. Anorexia
6. Nausea and vomiting
7. Hepatoxicity
8. Alopecia
9. Ulcerative stomatitis
10. Leukopenia
11. Chills and fever
12. Photosensivity
13. Thrombocytopenia
14. Hyperurecemia

Dosage

Choriocarcinoma and similar trophoblastic neoplasms

PO/IM: 15-30 mg daily for a 5-day course. The courses are usually repeated 3-5 times as required with a rest period of 1 week or more in between.

Leukemia

PO (adults): 3.3 mg/m2 in combination with Prednisone 60 mg/m2 daily for the induction phase of the therapy.

PO/IM (adults): 20-30 mg/m2 twice weekly for the maintenance phase of the therapy.

IV (adults): 2.5 mg/kg every 2 weeks

IT (adults): 12 mg/m2 or 15 mg
IT (children >3 years): 12 mg

IT (children 2 years): 10 mg

IT (children 1 yr): 8 mg

IT (children <1 yr): 6 mg

Psoriasis

PO (Adults): 2.5-5 mg every 12 hours for 3 doses or every 8 hours for 4 doses once weekly (not to exceed 30 mg/week)

Nursing Considerations

Assessment

Monitor the client taking Methotrexate for:

• Abdominal pain, diarrhea or ulcerative stomatitis.

Therapy may be discontinued with the presence of these toxic effects otherwise, hemorrhagic enteritis and death from intestinal perforation may occur.

• Symptoms of pulmonary toxicity, which may manifest early as a dry and nonproductive cough.
• Symptoms of gout due to increased uric acid. (edema, joint pain)

Laboratory Tests

• CBC (WBC and Platelet)
• Renal function (BUN and Creatinine)
• Hepatic function (AST, ALT, bilirubin)
• Serum Uric Acid concentration

Precautions

Extra precautions in administering Methotrexate should be observed in the following conditions:

• Preexisting liver damage or impaired hepatic function

Methotrexate may be hepatotoxic. Even without previous signs of GI or hematologic toxicity such as liver atrophy, necrosis and cirrhosis. Special caution should be observed in clients with preexisting liver damage or impaired hepatic function.

• Presence of infection, peptic ulcer, ulcerative colitis, geriatric patients or patients with chronic debilitating illnesses.

This drug has an immunosuppressive action. Thus, extreme caution should be observed in patients where immune responses may be vital for healing from a certain disease.

• Impaired renal function

Toxicity and Overdose

If Methotrexate is administered in high doses, the patient must receive Leucovorin Calcium rescue within 24-48 hours to prevent fatal toxicity.

Interventions

1. Solutions for injection must be prepared in a biologic cabinet. Gloves, gown and mask are worn while preparing and handling the medication.
2. Administer Allopurinol per doctor’s order to decrease uric acid levels.
3. Instruct patient to avoid caffeine as it may decrease the efficacy of the drug.
4. To prevent hematologic toxicity (platelet levels are decreased) salicylates, NSAIDs, phenytoin, tetracycline and chlorampenicol should be avoided.

images from bedfordlabs.com, johnsonintegrativehealth.com

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Mannitol

Brand Name: Osmitrol, Resectisol

Classification: Osmotic Diuretic

Action Summary

Half-life	Onset	Peak	Duration
100 minutes	30-60 minutes	1 hour	6-8 hours

Indications

1. Acute oliguric renal failure
2. Toxic overdose
3. Edema
4. Increased intracranial pressure (ICP)
5. Intraocular pressure (IOP)

Action

1. In the oliguric phase of acute renal failure, Mannitol increases osmotic pressure (pressure needed to stop the absorption of something or osmosis) of the glumerular filtrate, thereby,promoting diuresis (treating the oliguric phase of renal failure) and excretes toxic materials (management for toxic overdose).
2. It also elevates blood plasma osmolality thus, inhibiting the reabsorption of water and electrolytes (for relief of edema) and mobilizing fluids in the cerebral and ocular spaces(lowers intracranial or intraocular pressure).

Contraindications

1. Susceptibility
2. Dehydration

Adverse reactions

1. Dehydration
2. Anuria
3. Intracranial bleeding
4. Headache
5. Blurred vision
6. Nausea and vomiting
7. Volume expansion
8. Chest pain
9. Pulmonary edema
10. Thirst
11. Tachycardia
12. Hypokalemia (increases the risk of digoxin toxicity)
13. Chronic renal failure

Dosage

Adult

Oliguria: 50-100 g as a 5-25% solution.

Intracranial/Intraocular pressure: 0.25-2 g/kg as 15-25% solution administered for 30-60 minutes.

Children

Oliguria: 0.25-2 g/kg as a 15-20% solution for 2-6 hours

Intracranial/Intraocular pressure: 1-2 g/kg as a 15-20% solution administered for 30-60 minutes.

Nursing considerations

Assessment – Monitor the following:

1. 1. Vital signs
2. 2. Intake and output
3. 3. Central venous pressure
4. Pulmonary artery pressure
5. Signs and symptoms of dehydration (e.g. poor skin turgor, dry skin, fever, thirst)
6. Sign of electrolyte imbalance/deficit (e.g. muscular weakness, paresthesia, numbness, confusion, tingling sensation of extremity and excessive thirst)
7. (for increase ICP) Neurologic status and intracranial pressure readings.
8. (for increase IOP) Elevating eye pain or decreased visual acuity.

Laboratory Tests

1. Renal function (BUN and Creatinine)
2. Serum Electrolyte (Sodium and Potassium)

Precaution

Pregnancy and lactation (safe use during these conditions is not established)

Interventions

1. Observe the IV site regularly for infiltration.
2. Administration rate for oliguria should be titrated to produce a urine output. (about 30-50 ml/hr in adult and 2-6 hours in children)

image from mannitol.org

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