Medical and Mathematical Fundamentals Review

Comprehensive vocabulary review covering mental math shortcuts, ECG interpretation principles, major medications, nursing ethics, and clinical vital sign ranges.

Multiplication Short Trick (Tens Part)

For products like $12 \times 18$, multiply the first digit by the next consecutive number (e.g., $1 \times 2 = 2$).

Multiplication Short Trick (Ones Part)

Multiply the digits in the ones place (e.g., $2 \times 8 = 16$) and append it to the tens part.

ECG (Electrocardiogram)

A record of the electrical activity of the heart.

Systematic ECG Approach

A 10-step method involving: 1. Rate, 2. Rhythm, 3. P Waves, 4. PR Interval, 5. QRS Complex, 6. QT Interval, 7. QRS Axis, 8. ST Segment, 9. T Waves, and 10. Overall Interpretation.

Heart Rate (Regular Rhythm)

Calculated as $300 \div \text{number of large squares between two R waves}$.

Heart Rate (Irregular Rhythm)

Calculated by counting the number of QRS complexes in $6\,\text{seconds}$ and multiplying by $10$.

Bradycardia

A heart rate of less than $60\,\text{BPM}$.

Tachycardia

A heart rate of greater than $100\,\text{BPM}$.

Normal Regular Rhythm

Characteristic rhythm where R-R intervals are equal and every QRS is preceded by a P wave.

Normal P Wave

Duration is less than $0.12\,\text{second}$, best seen in Lead II, and upright in most leads.

PR Interval

Measured from the start of the P wave to the start of the QRS complex; normal range is $0.12$ to $0.20\,\text{second}$ ($3$-$5$ small squares).

Horizontal Axis (Standard ECG Paper)

$1\,\text{small square} = 0.04\,\text{second}$ ($1\,\text{mm}$) and $1\,\text{large square} = 0.20\,\text{second}$ ($5\,\text{mm}$).

Vertical Axis (Standard ECG Paper)

$1\,\text{small square} = 0.1\,\text{mV}$ and $1\,\text{large square} = 0.5\,\text{mV}$.

Standard ECG Calibration

Standardized at $25\,\text{mm/second}$ where $10\,\text{mm} = 1\,\text{mV}$.

QT Interval

Represents ventricular depolarization and repolarization, measured from the beginning of the QRS to the end of the T wave.

Bazett Formula

Common correction for the QT interval: $QTc = \frac{QT}{\sqrt{RR}}$.

ST Segment

Measured from the end of the QRS complex to the beginning of the T wave.

ST Elevation

The ST segment is above the isoelectric line; may indicate acute injury such as STEMI.

ST Depression

The ST segment is below the isoelectric line; may indicate ischemia, Dig effect, or electrolyte imbalance.

Normal QRS Axis

Ranges approximately from $-30^\circ$ to $+90^\circ$.

Metoprolol (Lopressor)

A Beta blocker used for hypertension, angina, and heart failure; hold if heart rate is less than $60\,\text{BPM}$.

Digoxin (Lanoxin)

A Cardiac glycoside used for heart failure and atrial fibrillation; target therapeutic level is $0.5$-$2.0\,\text{ng/mL}$.

Lisinopril (Prinivil, Zestril)

An ACE inhibitor used for hypertension and heart failure; side effects include dry cough, hyperkalemia, and life-threatening angioedema.

Enoxaparin (Lovenox)

An anticoagulant (low molecular weight heparin) used for DVT prevention and treatment; must be injected into the abdomen and monitored for HIT (platelets).

Furosemide (Lasix)

A Loop diuretic used for edema and heart failure; side effects include hypokalemia and dehydration.

Warfarin (Coumadin)

An oral anticoagulant with a target INR of $2$-$3$; Vitamin K is the antidote.

Levothyroxine (Synthroid)

A thyroid hormone used for hypothyroidism; should be taken in the morning on an empty stomach.

Morphine

An opioid analgesic for severe pain; monitor for respiratory depression and pinpoint pupils; antidote is Naloxone.

Five Rights of Medication Administration

Right patient, right drug, right dose, right route, right time.

The ABCs of Emergency Assessment

A: Airway, B: Breathing, C: Circulation.

Pulse Oximeter

A device used to measure oxygen saturation ($SpO_2$).

Glasgow Coma Scale (GCS)

Assesses level of consciousness via eye, verbal, and motor components; maximum score is $15$.

Autonomy

The ethical principle of respecting a patient's right to make decisions.

Non-maleficence

The ethical principle of 'do no harm'.

Beneficence

The ethical principle of 'doing good' for the patient.

Tachycardia (Cardiology Definition)

Heart rate greater than $100\,\text{beats/min}$.

Myocardial Infarction (MI)

Death of heart muscle due to blockage; clinical indicators include chest pain, elevated Troponin, and ECG changes.

Atherosclerosis

Plaque buildup in arteries causing narrowing.

Syncope

Temporary loss of consciousness due to reduced blood flow to the brain.

Gastric Glands

Secrete HCl (acidic medium), Mucus (protection), and Pepsin (protein breakdown).

Liver Secretions

Produces Bile juice for the emulsification of fat, which is stored in the gallbladder.

Pancreatic Juice

Contains Trypsin (protein breakdown) and Lipase (fat breakdown).

Male Hemoglobin (Normal)

$13$-$17\,\text{g/dl}$.

Potassium (Normal)

$3.50$-$5.00\,\text{mEq/L}$.

Normal Blood Pressure

$120/80\,\text{mmHg}$.