BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
BSN 266 HESI BUNDLE
Nightingale College · 2026
All Versions: V1 · V2 · Practice · Assessment
Questions & Answers | Latest Update 2026 Exam Prep
✓ Graded A+ | ✓ Correct Answers Highlighted in Green
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Topics Covered:
✦ Fundamentals & Safety
✦ Cardiovascular & Respiratory
✦ Neurological & Endocrine
✦ Renal & GI Systems
✦ Pharmacology & Medication Math
✦ Mental Health & Psychiatric Nursing
✦ Maternal-Newborn & Pediatrics
✦ Oncology & Critical Care
✦ Medical-Surgical Nursing
✦ Community & Leadership
Page 1 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
, BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
HOW TO USE THIS STUDY GUIDE
1. Green highlighted answers with ✓ checkmarks indicate the CORRECT response to each question.
2. Read all answer choices carefully before selecting — HESI uses priority/best action questions.
3. Apply ABC (Airway, Breathing, Circulation) and Maslow's Hierarchy when prioritizing.
4. For pharmacology questions: know mechanism of action, side effects, nursing considerations, and
antidotes.
5. SATA (Select All That Apply) questions: treat each option independently as True or False.
6. Use the RACE mnemonic for fire and similar for other emergency scenarios.
7. Review answer rationales thoroughly — understanding WHY is more important than memorizing answers.
8. Practice medication math calculations daily without a calculator for HESI preparation.
Page 2 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
, BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
CRITICAL NORMAL LAB VALUES — QUICK REFERENCE
Sodium (Na+): 136-145 mEq/L — Hyponatremia <136 / Hypernatremia >145
Potassium (K+): 3.5-5.0 mEq/L — Hypokalemia <3.5 / Hyperkalemia >5.0
Chloride (Cl-): 98-106 mEq/L
Bicarbonate (HCO3-): 22-26 mEq/L — Acidosis <22 / Alkalosis >26
BUN: 10-20 mg/dL — >20 may indicate renal impairment or dehydration
Creatinine: 0.6-1.2 mg/dL — >1.2 suggests renal dysfunction
Glucose (fasting): 70-110 mg/dL — Hypoglycemia <70 / Hyperglycemia >126
HbA1c: <5.7% normal — Diabetes: ≥6.5%; Goal: <7% for diabetics
Hemoglobin: 12-17 g/dL (F: 12-16; M: 14-18) — Anemia if below; transfuse if <7 g/dL symptomatic
Hematocrit: 36-54% (F: 36-46; M: 42-54)
WBC: 5,000-10,000/mm3 — >10,000 infection; <5,000 leukopenia
Platelets: 150,000-400,000/mm3 — <50,000 bleeding risk; <20,000 spontaneous bleed
INR (on warfarin): 2.0-3.0 (2.5-3.5 for mechanical valves) — >4.0 = toxicity risk
aPTT (on heparin): 1.5-2.5x control (60-100 sec) — Monitor every 6 hours
pH (arterial): 7.35-7.45 — Acidosis <7.35 / Alkalosis >7.45
PaCO2: 35-45 mmHg — >45 respiratory acidosis; <35 respiratory alkalosis
PaO2: 80-100 mmHg — <60 = hypoxemia, supplemental O2 needed
SpO2: 95-100% — <90% = critical; <88% = COPD acceptable target
HCO3-: 22-26 mEq/L — Metabolic indicator
Digoxin: 0.5-2.0 ng/mL — >2.0 = toxicity; hold if HR <60 or toxicity signs
Lithium: 0.6-1.2 mEq/L — >1.5 = toxicity; >2.0 = severe toxicity
Theophylline: 10-20 mcg/mL — >20 = toxicity (seizures, dysrhythmias)
Phenytoin (Dilantin): 10-20 mcg/mL — Monitor for nystagmus, ataxia at toxic levels
Vancomycin trough: 10-20 mg/L — Check trough 30 min before next dose
Albumin: 3.5-5.0 g/dL — <3.5 = malnutrition; affects medication binding
Total bilirubin: 0.2-1.2 mg/dL — >1.2 = jaundice, liver dysfunction
ALT/AST: ALT: 7-56 U/L; AST: 10-40 U/L — Elevated = liver damage
Magnesium: 1.5-2.5 mEq/L — Toxicity in pre-eclampsia treatment — monitor reflexes
Calcium: 8.5-10.5 mg/dL — Hypocalcemia: Trousseau/Chvostek signs, tetany
Phosphorus: 2.5-4.5 mg/dL — Low in malnutrition/refeeding syndrome
Page 3 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
, BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
ACID-BASE BALANCE — ABG INTERPRETATION GUIDE
Step-by-Step ABG Interpretation (ROME Method):
STEP 1: Look at pH — <7.35 = ACIDOSIS; >7.45 = ALKALOSIS
STEP 2: Look at PaCO2 — if pH is ACIDOSIS and CO2 is HIGH → RESPIRATORY ACIDOSIS
STEP 3: Look at HCO3 — if pH is ACIDOSIS and HCO3 is LOW → METABOLIC ACIDOSIS
STEP 4: Determine Compensation — if both CO2 and HCO3 are abnormal, compensation is occurring
ROME: Respiratory Opposite (pH↓/CO2↑ or pH↑/CO2↓); Metabolic Equal (pH↓/HCO3↓ or pH↑/HCO3↑)
Respiratory Acidosis
pH: pH↓ | PaCO2: CO2↑ | HCO3: HCO3 normal (uncomp) or ↑ (comp) Causes: COPD, Hypoventilation, Opioid OD
Respiratory Alkalosis
pH: pH↑ | PaCO2: CO2↓ | HCO3: HCO3 normal (uncomp) or ↓ (comp) Causes: Hyperventilation, Anxiety,
Mechanical Vent
Metabolic Acidosis
pH: pH↓ | PaCO2: CO2 normal (uncomp) or ↓ (comp) | HCO3: HCO3↓ Causes: DKA, Renal failure, Diarrhea, Lactic
acidosis
Metabolic Alkalosis
pH: pH↑ | PaCO2: CO2 normal (uncomp) or ↑ (comp) | HCO3: HCO3↑ Causes: Vomiting, NG suction, Excess
antacids
Page 4 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
BSN 266 HESI BUNDLE
Nightingale College · 2026
All Versions: V1 · V2 · Practice · Assessment
Questions & Answers | Latest Update 2026 Exam Prep
✓ Graded A+ | ✓ Correct Answers Highlighted in Green
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Topics Covered:
✦ Fundamentals & Safety
✦ Cardiovascular & Respiratory
✦ Neurological & Endocrine
✦ Renal & GI Systems
✦ Pharmacology & Medication Math
✦ Mental Health & Psychiatric Nursing
✦ Maternal-Newborn & Pediatrics
✦ Oncology & Critical Care
✦ Medical-Surgical Nursing
✦ Community & Leadership
Page 1 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
, BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
HOW TO USE THIS STUDY GUIDE
1. Green highlighted answers with ✓ checkmarks indicate the CORRECT response to each question.
2. Read all answer choices carefully before selecting — HESI uses priority/best action questions.
3. Apply ABC (Airway, Breathing, Circulation) and Maslow's Hierarchy when prioritizing.
4. For pharmacology questions: know mechanism of action, side effects, nursing considerations, and
antidotes.
5. SATA (Select All That Apply) questions: treat each option independently as True or False.
6. Use the RACE mnemonic for fire and similar for other emergency scenarios.
7. Review answer rationales thoroughly — understanding WHY is more important than memorizing answers.
8. Practice medication math calculations daily without a calculator for HESI preparation.
Page 2 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
, BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
CRITICAL NORMAL LAB VALUES — QUICK REFERENCE
Sodium (Na+): 136-145 mEq/L — Hyponatremia <136 / Hypernatremia >145
Potassium (K+): 3.5-5.0 mEq/L — Hypokalemia <3.5 / Hyperkalemia >5.0
Chloride (Cl-): 98-106 mEq/L
Bicarbonate (HCO3-): 22-26 mEq/L — Acidosis <22 / Alkalosis >26
BUN: 10-20 mg/dL — >20 may indicate renal impairment or dehydration
Creatinine: 0.6-1.2 mg/dL — >1.2 suggests renal dysfunction
Glucose (fasting): 70-110 mg/dL — Hypoglycemia <70 / Hyperglycemia >126
HbA1c: <5.7% normal — Diabetes: ≥6.5%; Goal: <7% for diabetics
Hemoglobin: 12-17 g/dL (F: 12-16; M: 14-18) — Anemia if below; transfuse if <7 g/dL symptomatic
Hematocrit: 36-54% (F: 36-46; M: 42-54)
WBC: 5,000-10,000/mm3 — >10,000 infection; <5,000 leukopenia
Platelets: 150,000-400,000/mm3 — <50,000 bleeding risk; <20,000 spontaneous bleed
INR (on warfarin): 2.0-3.0 (2.5-3.5 for mechanical valves) — >4.0 = toxicity risk
aPTT (on heparin): 1.5-2.5x control (60-100 sec) — Monitor every 6 hours
pH (arterial): 7.35-7.45 — Acidosis <7.35 / Alkalosis >7.45
PaCO2: 35-45 mmHg — >45 respiratory acidosis; <35 respiratory alkalosis
PaO2: 80-100 mmHg — <60 = hypoxemia, supplemental O2 needed
SpO2: 95-100% — <90% = critical; <88% = COPD acceptable target
HCO3-: 22-26 mEq/L — Metabolic indicator
Digoxin: 0.5-2.0 ng/mL — >2.0 = toxicity; hold if HR <60 or toxicity signs
Lithium: 0.6-1.2 mEq/L — >1.5 = toxicity; >2.0 = severe toxicity
Theophylline: 10-20 mcg/mL — >20 = toxicity (seizures, dysrhythmias)
Phenytoin (Dilantin): 10-20 mcg/mL — Monitor for nystagmus, ataxia at toxic levels
Vancomycin trough: 10-20 mg/L — Check trough 30 min before next dose
Albumin: 3.5-5.0 g/dL — <3.5 = malnutrition; affects medication binding
Total bilirubin: 0.2-1.2 mg/dL — >1.2 = jaundice, liver dysfunction
ALT/AST: ALT: 7-56 U/L; AST: 10-40 U/L — Elevated = liver damage
Magnesium: 1.5-2.5 mEq/L — Toxicity in pre-eclampsia treatment — monitor reflexes
Calcium: 8.5-10.5 mg/dL — Hypocalcemia: Trousseau/Chvostek signs, tetany
Phosphorus: 2.5-4.5 mg/dL — Low in malnutrition/refeeding syndrome
Page 3 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
, BSN 266 HESI Bundle — Nightingale College 2026 | All Versions | Graded A+
ACID-BASE BALANCE — ABG INTERPRETATION GUIDE
Step-by-Step ABG Interpretation (ROME Method):
STEP 1: Look at pH — <7.35 = ACIDOSIS; >7.45 = ALKALOSIS
STEP 2: Look at PaCO2 — if pH is ACIDOSIS and CO2 is HIGH → RESPIRATORY ACIDOSIS
STEP 3: Look at HCO3 — if pH is ACIDOSIS and HCO3 is LOW → METABOLIC ACIDOSIS
STEP 4: Determine Compensation — if both CO2 and HCO3 are abnormal, compensation is occurring
ROME: Respiratory Opposite (pH↓/CO2↑ or pH↑/CO2↓); Metabolic Equal (pH↓/HCO3↓ or pH↑/HCO3↑)
Respiratory Acidosis
pH: pH↓ | PaCO2: CO2↑ | HCO3: HCO3 normal (uncomp) or ↑ (comp) Causes: COPD, Hypoventilation, Opioid OD
Respiratory Alkalosis
pH: pH↑ | PaCO2: CO2↓ | HCO3: HCO3 normal (uncomp) or ↓ (comp) Causes: Hyperventilation, Anxiety,
Mechanical Vent
Metabolic Acidosis
pH: pH↓ | PaCO2: CO2 normal (uncomp) or ↓ (comp) | HCO3: HCO3↓ Causes: DKA, Renal failure, Diarrhea, Lactic
acidosis
Metabolic Alkalosis
pH: pH↑ | PaCO2: CO2 normal (uncomp) or ↑ (comp) | HCO3: HCO3↑ Causes: Vomiting, NG suction, Excess
antacids
Page 4 | BSN 266 HESI 2026 | Nightingale College | Exam Prep | A+
