MK Lecture 9: Blood Counts and Psychotropic Pharmacology

Understanding Blood Counts and Lab Value Prioritization

• Platelet Count Interpretation:

  • In a clinical setting, healthcare providers often shorten platelet counts. If a provider says a patient has "40 platelets" or "35 platelets," they mean $40,000$ or $35,000$ platelets per $mm^3$.

  • If a platelet count is reported as "three," it means $3,000$, not three individual platelets.

• Absolute Neutrophil Count (ANC): This value is usually reported in the thousands.

• Red Blood Cell (RBC) Count: The normal range is $4 \times 10^6$ to $6 \times 10^6$ (4 to 6 million). An abnormal red count is classified as a "B" priority (no big deal/low priority).

The Five D's: Highest Medical Priorities

The "Five D's" represent high-priority lab values that indicate a patient is unsafe and requires immediate intervention. These are the highest priority patients on a hospital unit.

• 1. $pH$ in the 6s: A $pH$ level below $7.0$ is a critical emergency.

• 2. Potassium ($K^+$) in the 6s: Potassium levels in the 6s ($6.0\,mEq/L$ or higher) are life-threatening.

• 3. $CO_2$ in the 60s: High carbon dioxide levels in the 60s indicate severe respiratory distress.

• 4. $O_2$ in the 60s: Low oxygen levels in the 60s indicate extreme hypoxia.

• 5. Platelet Count less than $40,000$: This signifies a high risk for spontaneous hemorrhage.

General Principles of Psychotropic Medications

• Universal Side Effects: All psychotropic medications cause low blood pressure (hypotension) and weight changes.

• Weight Changes: The vast majority of psych drugs cause weight increase.

• Prozac Exception: While weight loss is more common with Prozac, it can technically cause both weight loss and weight gain.

Phenothiazines: First Generation (Typical) Antipsychotics

• Classification: Known as "first-generation" or "typical" antipsychotics.

• Naming Convention: All drugs in this class end in the suffix "-zine" (e.g., Thorazine, Stelazine, Fluphenazine, Hyperazine, Cloprimazine, Hydroxazine).

• Action: They do not cure psychiatric diseases; they only reduce symptoms.

  • Large Doses: Used as antipsychotics. Mnemonic: "Zines for the Zany."

  • Small Doses: Used as anti-emetics to treat nausea (e.g., Compazine, Phenergan/Promethazine, Vistaril/Hydroxyzine).

• Tranquilizer Analogy: Phenothiazines are to tranquilizers what aminoglycosides are to antibiotics—they are the "big guns" pulled out when nothing else works.

• Side Effects (The ABCDEFG List):

  • A: Anticholinergic effect (primarily dry mouth).

  • B: Blurred vision.

  • C: Constipation.

  • D: Drowsiness.

  • E: Extrapyramidal Syndrome (EPS). This looks like Parkinson's disease, involving pill rolling, cogwheel rigidity, and a shuffling gait.

  • F: Photosensitivity (skin burns easily in light).

  • G: A-granulocytosis (immunosuppression/low white blood cell count).

• Nursing Care and Safety:

  • For side effects, the nurse should teach the patient, inform the doctor, and continue giving the medication.

  • For toxic effects (severe reactions), hold the drug and call the doctor immediately.

  • Primary Nursing Diagnosis: Risk for injury/safety due to side effects like drowsiness, blurred vision, and EPS.

• Deconate (D) Form: If a drug name is followed by a "D" (e.g., Thorazine D), it indicates a long-acting injectable form (lasting 2 weeks to a month) often used for non-compliant clients. This can be court-ordered.

Tricyclic Antidepressants (TCAs)

• Classification: Mood elevators used to treat depression. Now often classified as NSSRIs (Non-selective serotonin reuptake inhibitors).

• Examples: Elavil, Tofranil, Aventyl, and Deseril.

• Mnemonic: "Elavil elevates" the mood.

• Side Effects (ABCDE):

  • A: Anticholinergic (dry mouth).

  • B: Blurred vision.

  • C: Constipation.

  • D: Drowsiness.

  • E: Euphoria (excessive happiness).

• Timeline: Beneficial effects take approximately 2 to 4 weeks to manifest. Patients must be taught that the drug will not work right away.

Benzodiazepines: Minor Tranquilizers

• Naming Convention: These drugs always contain "ZEP" in the name (e.g., Diazepam, Lorazepam, Fluazepam, Chlorazepam, Chlordiazepoxide).

• Classification: Minor tranquilizers. Mnemonic: "Minors on tranquilizers at a Led Zeppelin concert."

• Indications:

  • Pre-operative induction of anesthesia.

  • Muscle relaxant.

  • Alcohol withdrawal.

  • Seizures.

  • Relaxation for patients on mechanical ventilators.

• Onset and Duration: They work quickly but should not be taken for more than 2 to 4 weeks.

• Heparin/Coumadin Analogy: Benzodiazepines are like Heparin (fast-acting, short-term use), while antidepressants are like Coumadin (slow-acting, long-term use). A patient may start both simultaneously until the antidepressant kicks in.

• Side Effects (ABCD): Anticholinergic, Blurred vision, Constipation, and Drowsiness.

Monamine Oxidase Inhibitors (MAOIs)

• Naming Convention: Trade names rhyme: Marplan, Nardil, Parnate (MAR, NAR, PAR).

• Primary Danger: Hypertensive Crisis. To prevent fatal high blood pressure, patients must avoid all foods containing Tyramine.

• The Tyramine-Restricted Diet:

  • Fruits/Veggies: Generally okay, except for the "BAR" list: Bananas, Avocados (including guacamole), and Raisins (or any dried fruit).

  • Grains: Generally fine (bread, cookies, cakes).

  • Meats: No organ meats (liver, kidney, tripe, heart, lung, etc.) and no preserved meats (smoked, dried, cured, pickled, or processed meats like hot dogs).

  • Dairy: No aged cheeses. Only Mozzarella and Cottage Cheese are permitted. No yogurt.

  • Other: No alcohol, caffeine, chocolate, licorice, or soy sauce. No over-the-counter (OTC) medications.

Lithium

• Classification: An electrolyte used to treat the mania associated with Bipolar Disorder. It does not treat depression.

• Mechanism: Stabilizes nerve cell membranes rather than messing with neurotransmitters.

• Side Effects (The Three P's):

  • P: Peeing (polyuria).

  • P: Pooping (diarrhea).

  • P: Paresthesia (numbness and tingling—the earliest sign of all electrolyte imbalances).

• Toxic Effects: Tremors, metallic taste, and severe diarrhea. If these occur, hold the drug and call the doctor.

• Nursing Interventions:

  • Increase fluid intake due to high fluid loss from polyuria.

  • Monitor Sodium ($Na^+$) levels. Lithium and Sodium are competitive binders.

  • Low Sodium: Makes Lithium toxic.

  • High Sodium: Makes Lithium ineffective.

Prozac (Fluoxetine): SSRI

• Classification: Selective Serotonin Reuptake Inhibitor.

• Side Effects: ABCDE (including Euphoria).

• Administration Timing: Prozac causes insomnia. It should be given before 12:00 PM (noon).

• Suicide Risk: There is an increased risk of suicidal ideation in adolescents and young adults specifically when the dose is changed.

Haloperidol (Haldol) and Neuroleptic Malignant Syndrome (NMS)

• Classification: Typical first-generation antipsychotic, similar to phenothiazines.

• Side Effects: ABCDEFG.

• Neuroleptic Malignant Syndrome (NMS):

  • A medical emergency involving fatal hyperpyrexia (temp > 102^{\circ}F, potentially up to $108^{\circ}F$).

  • Affects elderly and young white schizophrenic patients.

  • Symptoms include tremors, anxiety, and confusion.

• Differentiating NMS from EPS: Both NMS and EPS cause tremors. The nurse must take the patient's temperature. High fever indicates NMS (emergency); absence of fever indicates EPS (side effect).

Clozapine (Clozaril): Atypical Antipsychotic

• Classification: Original "atypical" second-generation antipsychotic.

• Advantage: Lacks most of the ABCDEF side effects.

• Disadvantage: Causes severe Agranulocytosis. It trashes bone marrow, leading to dangerously low white counts and massive infections.

• Nursing Action: Frequent monitoring of white blood cell (WBC) counts is mandatory.

• Geodon (Ziprasidone): Has a binary "Black Box" warning. It prolongs the QT interval and can cause sudden cardiac arrest.

Sertraline (Zoloft): SSRI

• Classification: SSRI. Also causes insomnia, though the speaker notes it is sometimes given at bedtime.

• Drug-Drug Interactions: Sertraline interferes with the Cytochrome P450 system in the liver, preventing other drugs from being broken down. This leads to drug toxicities.

• Specific Interactions:

  • St. John's Wort: Combining with Zoloft causes Serotonin Syndrome. Symptoms are categorized by the mnemonic "SAD Head": Sweating, Apprehension (impending sense of doom), Dizziness, and Headache.

  • Warfarin (Coumadin): Zoloft makes Coumadin toxic. Patients must reduce their Coumadin dose or watch for increased bleeding.

Questions & Discussion

• Question on Platelet Counts: If a speaker says a patient's platelet count is "three," what does that mean?

• Response: It means $3,000$.

• Discussion on Haldol and NMS: The lecturer tells an anecdote about a clinical rotation where a student identified a temperature of $102.8^{\circ}F$ in a patient displaying tremors/anxiety, identifying early NMS that staff nurses had overlooked.

• Analogy Discussion: The lecturer uses various analogies to reinforce learning, such as comparing typical antipsychotics to aminoglycoside antibiotics and comparing tranquilizer/antidepressant onset to Heparin/Coumadin transitions.