Pathophysiology NCLEX Questions
Question A 45-year-old patient presents with chest pain, dyspnea, and palpitations. An electrocardiogram (ECG) shows ST-segment elevation. Which of the following is the most likely diagnosis? A. Stable angina B. Myocardial infarction C. Aortic dissection D. Pulmonary embolism E. Pericarditis
Correct Answer: B. Myocardial infarction
Rationale: The presentation of chest pain with ST-segment elevation on the ECG is indicative of myocardial infarction (MI). Stable angina typically does not cause ST-segment changes on an ECG. Aortic dissection and pulmonary embolism have distinct clinical presentations and ECG findings that differ from those of MI. Pericarditis may cause diffuse ST-segment elevation, but the clinical context favors MI given the symptoms described.
Question A patient with a history of type 2 diabetes mellitus presents with increased thirst, frequent urination, and blurred vision. Which of the following pathophysiological processes is most likely responsible for these symptoms? A. Hypoglycemia B. Ketoacidosis C. Hyperosmolar hyperglycemic state D. Insulin resistance E. Glucagon deficiency
Correct Answer: C. Hyperosmolar hyperglycemic state
Rationale: The symptoms of increased thirst (polydipsia), frequent urination (polyuria), and blurred vision are indicative of hyperglycemia, which is characteristic of a hyperosmolar hyperglycemic state (HHS). HHS is more common in patients with type 2 diabetes. Hypoglycemia presents with different symptoms, such as sweating, tremors, and confusion. Ketoacidosis is more typical in type 1 diabetes, and insulin resistance and glucagon deficiency do not directly cause the acute symptoms described.
Question A patient is diagnosed with congestive heart failure (CHF) and has symptoms of shortness of breath, fatigue, and peripheral edema. Which of the following mechanisms primarily contributes to these symptoms? A. Decreased cardiac output B. Hyperthyroidism C. Reduced plasma albumin D. Ventricular hypertrophy E. Atherosclerosis
Correct Answer: A. Decreased cardiac output
Rationale: In congestive heart failure, the heart’s reduced ability to pump blood leads to decreased cardiac output, which is the primary mechanism causing symptoms of shortness of breath (due to pulmonary congestion), fatigue (due to inadequate perfusion of organs), and peripheral edema (due to fluid retention). Hyperthyroidism, reduced plasma albumin, ventricular hypertrophy, and atherosclerosis may contribute to or result from heart failure but do not directly cause the triad of symptoms described.
Question A 55-year-old patient presents with abdominal pain, jaundice, and weight loss. Imaging studies reveal a mass in the head of the pancreas. Which of the following is the most likely diagnosis? A. Pancreatic cancer B. Acute pancreatitis C. Cholecystitis D. Hepatic cirrhosis E. Peptic ulcer disease
Correct Answer: A. Pancreatic cancer
Rationale: The combination of abdominal pain, jaundice, and weight loss, along with imaging findings of a mass in the head of the pancreas, strongly suggests pancreatic cancer. Acute pancreatitis typically presents with severe abdominal pain but not necessarily with jaundice or a mass. Cholecystitis presents with right upper quadrant pain and fever. Hepatic cirrhosis and peptic ulcer disease have different clinical presentations and would not typically present with a pancreatic mass.
Question A patient presents with high fever, cough with purulent sputum, and chest pain that worsens with deep breathing. Chest X-ray reveals lobar consolidation. Which of the following organisms is most likely responsible for this patient’s condition? A. Streptococcus pneumoniae B. Mycobacterium tuberculosis C. Legionella pneumophila D. Haemophilus influenzae E. Staphylococcus aureus
Correct Answer: A. Streptococcus pneumoniae
Rationale: The clinical presentation of high fever, productive cough with purulent sputum, chest pain that worsens with deep breathing, and chest X-ray findings of lobar consolidation are characteristic of pneumococcal pneumonia, caused by Streptococcus pneumoniae. Mycobacterium tuberculosis causes tuberculosis, which typically presents with a chronic cough, night sweats, and weight loss. Legionella pneumophila, Haemophilus influenzae, and Staphylococcus aureus can cause pneumonia but are less likely to present with the classic lobar consolidation seen in pneumococcal pneumonia.
Question A 60-year-old patient with a history of hypertension and smoking presents with sudden onset of severe back pain and hypotension. A CT scan reveals an abdominal aortic aneurysm with signs of rupture. Which of the following risk factors is most directly associated with the development of this condition? A. Diabetes mellitus B. Hyperlipidemia C. Tobacco use D. Alcohol consumption E. Sedentary lifestyle
Correct Answer: C. Tobacco use
Rationale: Tobacco use is a major risk factor for the development of an abdominal aortic aneurysm (AAA) and its subsequent rupture. Smoking contributes to the degradation of the aortic wall by promoting atherosclerosis and increasing blood pressure, which can exacerbate an existing aneurysm. While diabetes mellitus, hyperlipidemia, alcohol consumption, and a sedentary lifestyle are risk factors for cardiovascular disease, tobacco use is most directly associated with the risk of AAA and its complications.
Question A patient presents to the emergency department with severe asthma exacerbation. Which of the following pathophysiological mechanisms primarily contributes to the acute respiratory distress observed in this condition? A. Alveolar hypoventilation B. Bronchial smooth muscle constriction C. Increased pulmonary capillary permeability D. Decreased surfactant production E. Pulmonary artery vasoconstriction
Correct Answer: B. Bronchial smooth muscle constriction
Rationale: In an acute asthma exacerbation, the primary pathophysiological mechanism causing respiratory distress is bronchial smooth muscle constriction, leading to airway narrowing and obstruction. This results in difficulty breathing, wheezing, and hypoxemia. Alveolar hypoventilation, increased pulmonary capillary permeability, decreased surfactant production, and pulmonary artery vasoconstriction are associated with other respiratory conditions but do not play a central role in the acute phase of asthma exacerbation.
Question A 50-year-old patient presents with fatigue, pale skin, and shortness of breath. Laboratory tests reveal microcytic hypochromic anemia. Which of the following is the most likely cause of this type of anemia? A. Vitamin B12 deficiency B. Iron deficiency C. Acute blood loss D. Chronic disease E. Hemolytic anemia
Correct Answer: B. Iron deficiency
Rationale: Microcytic hypochromic anemia is characterized by small, pale red blood cells and is most commonly caused by iron deficiency. This condition can result from inadequate dietary intake, malabsorption, or chronic blood loss. Vitamin B12 deficiency leads to macrocytic anemia, not microcytic. While acute blood loss, chronic disease, and hemolytic anemia can cause anemia, they do not typically result in the microcytic hypochromic presentation.
Question A patient diagnosed with rheumatoid arthritis (RA) complains of joint pain and stiffness, particularly in the mornings. Which of the following pathophysiological processes is primarily involved in RA? A. Degeneration of articular cartilage B. Autoimmune-mediated inflammation of synovial membranes C. Accumulation of uric acid crystals in joints D. Bacterial infection of the joint space E. Overuse of the affected joints
Correct Answer: B. Autoimmune-mediated inflammation of synovial membranes
Rationale: Rheumatoid arthritis is primarily an autoimmune disorder characterized by inflammation of the synovial membranes, leading to joint pain, stiffness, and eventually damage to joint structures. This inflammatory process is driven by the immune system mistakenly attacking the body’s own tissues. Degeneration of articular cartilage is more characteristic of osteoarthritis. Accumulation of uric acid crystals is seen in gout, not RA. Bacterial infection of the joint space and overuse are not primary mechanisms of RA.
Question A patient with chronic kidney disease (CKD) presents with elevated blood pressure, swelling in the legs, and fatigue. Which of the following complications is most directly related to these symptoms? A. Hyperkalemia B. Anemia C. Secondary hyperparathyroidism D. Fluid and electrolyte imbalance E. Uremic encephalopathy
Correct Answer: D. Fluid and electrolyte imbalance
Rationale: In patients with chronic kidney disease, the kidneys’ ability to manage fluid and electrolyte balance is compromised, leading to symptoms such as hypertension (due to fluid overload), swelling in the legs (edema), and fatigue. Hyperkalemia, anemia, and secondary hyperparathyroidism are also complications of CKD, but the combination of elevated blood pressure, swelling, and fatigue is most directly attributed to fluid and electrolyte imbalances. Uremic encephalopathy, while a serious complication of CKD, does not directly cause the symptoms described.
History: burned in an enclosed space but inhalation injury can occur outside, sore throat, throat tightness, difficulty breathing
Exam: face and/or neck burns, hoarse, tachypnea but may be ABSENT, coughing carbon debris, oropharyngeal edema, singed hair (facial, nares or scalp), stridor
There are two primary mechanisms of inhalation injury:
1) Carbon monoxide (CO) poisoning
• The Problem: CO binds to hemoglobin with a much greater affinity than oxygen
• SIGNS: Cherry red skin, anxious, confused
Measure the carboxyhemoglobin level (CarboxyHg)
CarboxyHg Level Symptoms
< 20 Headache, blurred vision
> 20 GI: nausea, vomiting
> 50 Seizure, death
2) Injury to the orophanyx and lungs
• Etiology: smoke, chemicals, heat
• Causes direct irritation to the tissues
PATHOPHYSIOLOGY of the injury: Most of the pathology is due to increased vascular permeability secondary to local inflammatory mediators. This results in fluid shifts and edema in the oropharnyx and in the lung. Direct chemical damage may occur to the epithelial cells lining the tracheobronchial tree.
How do you make the diagnosis?
Obtain a carboxyhemoglobin level
Not very helpful: O2 sat,
PaO2
CXR
Perform bronchoscopy
V/Q scan (historic importance) usually not readily available
What do you see at bronchoscopy?
(early) the mucosa appears edematous, erythematous, there is carbonaceous debris, the mucosa may just be pale
(at 48h) you may seeulceration, blood, blood clots, mucosal slough, thick secretions
What is the therapy for carbon monoxide poisoning?
Therapy is 100% O2 (this rapidly decreases the ½ life of carboxyhemoglobin rapidly).
Secure a patent airway. This is best done early, EDEMA/OBSTRUCTION MAY MAKE IT IMPOSSIBLE LATER!
• Consider use of a Volumetric Diffusive Respirator ventilator if available. This unfortunately is only available in some specialized burn centers. It is very effective at oxygenating and ventilating patients that otherwise may not be maintained on a volume-controlled ventilator
• Nebulized albuterol and heparin
• IPV (Intrapulmonary Percussive Ventilation) every 6 hours
• Mucomyst or pulmozyme if secretions become thick
• No prophylactic antibiotics
Scenarios to avoid with inhalation injury patients:
10 Anatomically difficult airway (get help)
9 Poor lighting
8 Uncontrolled setting i.e. on the ward
7 Tracheostomy or cricothyroidotomy not tray available (operator unprepared)
6 Anesthesia not available as backup
5 Hypoxic patient (hypoxic patients become agitated and combative)
4 You’re alone
3 Your assistant is inexperienced
2 You’re inexperienced
#1 Enroute by ground or flight (this is invariably disasterous)
PEARL: The safest time to intubate a patient with an inhalation injury is before he or she starts having respiratory distress. SECURE THE ENDOTRACHEAL TUBE WITH UMBILICAL TIES RATHER THAN TAPE WHICH WILL SLIDE OFF WHEN THE PATIENT BECOMES EDEMATOUS Although intubation is not a “benign” procedure, it may be the safest when nursing staff and monitoring is limited, nurse to patient ratio is low, in a MASCAL setting and during transport. So-called “crash intubations” require considerable skill to gain control of the airway. Attempts at surgical control of a loss airway are may result anoxic brain injury.
