NSG210 Week 01 Summary: Orientation, Calculation Review, Pharmacology Review
Week 01 runs August 24 through August 28, 2026. It has no lecture content of its own for Exam 1 in the sense of “new disease content” - it is prework: the Kaplan Pathophysiology Proctored Exam, a dosage calculation review, a three-part cardiac pharmacology review, and a maternal medication review. None of this is listed as “Exam 1 content” on the official schedule, but calculation quizzes recur all semester and several of these drug classes reappear directly in the Week 02 heart failure content, so this material stays relevant rather than being a one-time checkbox.
Dosage Calculation Review
Two formulas cover almost everything on the pretest.
Formula method for tablets/capsules/liquid volume:
Amount ordered divided by amount on hand, multiplied by the quantity that amount comes in, equals the number of tablets or the volume to give. For example, an order for ampicillin 500 mg from a supply labeled 250 mg per capsule: 500 divided by 250, times 1 capsule, equals 2 capsules.
IV flow rate (drops per minute):
Volume times drop factor, divided by time in minutes, equals drops per minute. For example, 1000 mL to run over 8 hours (480 minutes) with tubing that delivers 15 drops per mL: 1000 times 15, divided by 480, equals about 31 drops per minute.
Other calculation types on the pretest worth being fast at:
- Unit conversions: kg to lb (multiply by 2.2), mL to tsp, mcg to mg, g to mg, grains to mg (1 grain equals approximately 60 mg).
- Reconstituted IM doses (amount ordered over amount on hand, times volume, e.g. Ancef 400 mg IM from a 250 mg/mL reconstitution).
- Combining two IM medications into one syringe and giving a single total volume (e.g. Demerol and Vistaril together).
- Heparin drip calculations: converting units/hour to mL/hour using the concentration, and weight-based bolus dosing (units/kg, converting patient weight from lb to kg first).
- IV piggyback rates for a pump set in mL/hour rather than drops/minute (volume over time in hours).
- Working backward from a start time and a rate to find a completion time.
The heparin questions are the ones worth extra practice, since heparin dosing recurs as a running theme in both the pharmacology review (heparin nomogram, aPTT monitoring) and will keep showing up in later cardiac and OB units (anticoagulation in atrial fibrillation, VTE prophylaxis, etc).
Pharmacology Review Part 1: Nitrates, Beta Blockers, ACE Inhibitors, ARBs
Nitrates (nitroglycerin, isosorbide mononitrate/dinitrate) dilate coronary and systemic vessels, increasing myocardial oxygen supply and reducing preload by pooling blood in the periphery. Key safety points: never combine with sildenafil or other erectile dysfunction drugs within 24 hours (profound hypotension), build in an 8-10 hour nitrate-free period daily to prevent tolerance, keep the patient sitting or lying down when dosing to prevent syncope, and cap sublingual dosing at 3 tablets 5 minutes apart before calling for emergency help. Side effects are mostly vascular: headache (very common, about 50 percent), orthostatic hypotension, flushing, dizziness.
Beta blockers (“-lol” drugs: atenolol, metoprolol, propranolol, carvedilol, etc.) block beta-adrenergic stimulation, reducing heart rate, contractility, and automaticity - a triple negative chronotrope/inotrope/dromotrope effect. Used for hypertension, angina, and heart failure. Nursing priorities: take the apical pulse and blood pressure first and hold for HR under 60 or systolic under 100 (unless ordered otherwise); ask about asthma/COPD history since beta blockade can trigger bronchospasm; watch for masked hypoglycemia symptoms in diabetics; and never stop abruptly, since rebound hypertension, tachycardia, and even MI can follow sudden withdrawal.
ACE inhibitors (“-prils”: lisinopril, enalapril, captopril) block the conversion of angiotensin I to angiotensin II, preventing vasoconstriction and aldosterone-driven fluid retention. First-line for hypertension with diabetes (protects against diabetic nephropathy) and a foundation drug in heart failure. The signature side effect is a persistent dry cough (bradykinin accumulation) and the signature danger is angioedema. Contraindicated in pregnancy. Monitor potassium (tends to rise), renal function, and blood pressure before dosing.
ARBs (“-sartans”: losartan, valsartan, candesartan) act at the angiotensin II receptor rather than blocking the ACE enzyme, giving the same net antihypertensive effect without the cough - commonly substituted when a patient cannot tolerate an ACE inhibitor’s cough. Also avoid in pregnancy; monitor renal function and potassium.
Pharmacology Review Part 2: Calcium Channel Blockers, Direct Vasodilators, Alpha Blockers
Calcium channel blockers (diltiazem, verapamil, amlodipine, nifedipine) block calcium influx into cardiac and vascular smooth muscle, dilating coronary and peripheral arteries, slowing SA/AV node conduction, and lowering heart rate and afterload. Used for angina (including vasospastic/Prinzmetal’s), hypertension, and some supraventricular arrhythmias (IV form). Nursing priorities: hold for HR under 60 or systolic under 100, watch for peripheral edema and weight gain as early heart failure signs, and avoid grapefruit juice specifically with verapamil (it raises drug levels).
Direct-acting vasodilators (hydralazine, minoxidil, nitroprusside) relax arterial smooth muscle directly, lowering blood pressure but reflexively raising heart rate and cardiac output - sometimes used as heart failure adjuncts. IV forms require a large stable line, an infusion pump, and blood pressure checks every 5-15 minutes.
Central and peripheral alpha blockers (alpha-1 blockers like doxazosin/prazosin; alpha-2 agonists like clonidine/methyldopa) reduce sympathetic outflow and peripheral resistance. Clonidine carries a notable risk of severe rebound hypertension if stopped abruptly - never discontinue these medications suddenly.
Pharmacology Review Part 3: Anticoagulants and Antiplatelets
Warfarin (Coumadin) blocks vitamin K-dependent clotting factor production (extrinsic pathway). Monitored with PT and INR (therapeutic INR usually 2.0-3.0, higher for some indications). Full effect takes about a week, so it is often overlapped with heparin at the start of therapy. Contraindicated in pregnancy. Vitamin K is the antidote; patients should keep vitamin K intake consistent rather than avoiding or suddenly increasing green leafy vegetables. Given in the evening, after the day’s labs are drawn, so dosing can respond to that day’s INR.
Heparin (unfractionated or low molecular weight) inhibits thrombin and acts on the intrinsic pathway, monitored by aPTT (unfractionated) with a therapeutic target of about 1.5-2.0 times control. Protamine sulfate is the antidote. Low molecular weight heparin (enoxaparin/Lovenox) does not need routine aPTT monitoring and carries a lower bleeding risk. Watch for heparin-induced thrombocytopenia (HIT), a serious, potentially fatal complication that begins 3-12 days into therapy and presents as a falling platelet count.
Direct oral anticoagulants - dabigatran (Pradaxa, direct thrombin inhibitor) and rivaroxaban (Xarelto, factor Xa inhibitor) - do not require routine coagulation monitoring or dietary restriction, unlike warfarin. Both carry a bleeding risk as their main adverse effect.
Antiplatelet agents (aspirin, clopidogrel/Plavix, dipyridamole, ticlopidine) prevent platelet aggregation rather than acting on the clotting cascade, and are used for MI, stroke, and PAD prevention. Stop at least 7 days before planned surgery. Low-dose aspirin (81-325 mg) is the most common; enteric coating reduces but does not eliminate GI upset risk.
Maternal Medication Review
Grouped by clinical situation, high yield for both this week and the OB content later in the course:
- Prenatal: prenatal vitamins (folic acid, iron, DHA, vitamin D), iron and calcium supplements, antiemetics for nausea (ondansetron, promethazine, doxylamine-pyridoxine).
- Labor induction/augmentation: oxytocin (Pitocin) stimulates contractions; cervical ripening agents include misoprostol (Cytotec) and dinoprostone (Cervidil, Prepidil); amniotomy is a mechanical (non-drug) induction method.
- Tocolytics (suppress preterm labor): nifedipine, terbutaline (beta-agonist), magnesium sulfate (also neuroprotective), indomethacin (an NSAID, avoided later in gestation due to fetal ductus arteriosus/oligohydramnios risk).
- Labor pain management: epidural bupivacaine plus fentanyl, opioids (butorphanol, nalbuphine, morphine), nitrous oxide.
- Postpartum: uterotonics for hemorrhage (oxytocin, methylergonovine/Methergine, carboprost/Hemabate, misoprostol), RhoGAM for Rh-negative mothers, lactation support agents.
- Hypertensive disorders of pregnancy: labetalol, hydralazine, methyldopa, and magnesium sulfate specifically for seizure prophylaxis in preeclampsia/eclampsia.
- Fetal lung maturity: betamethasone or dexamethasone, given to stimulate fetal surfactant production when preterm birth is anticipated.
Memory anchors worth keeping: oxytocin causes tachysystole - stop the infusion if it occurs; magnesium sulfate toxicity shows up as decreased deep tendon reflexes, respiratory depression, and oliguria, with calcium gluconate as the antidote; methylergonovine is contraindicated in hypertension; carboprost is contraindicated in asthma; RhoGAM is only useful in an Rh-negative, unsensitized patient; terbutaline causes maternal/fetal tachycardia; indomethacin risks the fetal ductus arteriosus and amniotic fluid volume.