notes exam 2

Tissue Perfusion and Oxygenation

Tissue Perfusion

• Definition: Tissue perfusion is the flow of blood through capillaries to deliver oxygen and nutrients while removing waste products.

• Importance: Critical for maintaining cellular function and tissue viability.

Key Factors Affecting Tissue Perfusion

1. Cardiac Output: The heart must effectively pump blood; reduced output (e.g., heart failure) decreases perfusion.

2. Blood Pressure: Adequate blood pressure ensures blood flow; hypotension reduces perfusion while hypertension can damage vessels.

3. Blood Volume: Dehydration or blood loss diminishes circulating volume, impairing perfusion.

4. Vascular Integrity: Conditions such as arteriosclerosis or vasoconstriction negatively affect blood flow.

5. Hemoglobin Levels: Low levels (anemia) can lead to inadequate oxygen delivery to tissues.

Oxygenation

• Definition: The process of loading oxygen onto hemoglobin in the lungs and transporting it to tissues.

• Significance: Essential for cellular metabolism, energy production, and overall health of tissues.

Factors Affecting Oxygenation

1. Respiratory Function: The effectiveness of the lungs in oxygen uptake and carbon dioxide expulsion.

2. Hemoglobin Concentration: Insufficient hemoglobin results in reduced oxygen transport.

3. Ventilation-Perfusion Matching: Proper lung-blood exchange is necessary; conditions like pneumonia affect this.

4. Environmental Factors: High altitudes or pollution can reduce available oxygen.

Nursing Assessment for Perfusion and Oxygenation

• Vitals: Monitor blood pressure, heart rate, and respiratory rate.

• Peripheral Pulses: Evaluate strength and regularity.

• Capillary Refill: Should be less than 3 seconds.

• Oxygen Saturation: Use pulse oximetry to check SpO2 levels.

• Skin Color and Temperature: Look for signs of poor perfusion (cool, pale, cyanotic).

• Respiratory Sounds: Auscultate for wheezes, crackles, or stridor indicating impaired oxygenation.

Preoperative Nursing Role at Each Stage

Preoperative Phase

• Assessment:

  • Obtain thorough health history, including chronic conditions and allergies.

  • Perform physical assessments: vital signs, weight, height; cardiovascular and respiratory assessments.

  • Conduct diagnostic tests as ordered (CBC, electrolytes, EKG, chest X-ray).

  • Assess risk factors affecting anesthesia and wound healing (e.g., smoking, obesity).

• Education:

  • Provide instructions about fasting (NPO) before surgery.

  • Explain surgical procedures, pain management, and postoperative activities.

  • Discuss importance of deep breathing, coughing, and mobility to prevent complications.

• Psychological Support:

  • Address patient anxieties and misconceptions about surgery.

  • Offer emotional support and a safe space for questions.

• Preoperative Teaching:

  • Teach relaxation techniques (deep breathing, guided imagery).

  • Explain family roles in recovery.

• Physical Preparation:

  • Administer preoperative medications (antibiotics, sedatives).

  • Prepare the surgical site: clean, mark area.

  • Insert IV line for hydration and medication.

  • Ensure appropriate surgical attire, removal of jewelry or prosthetics.

Intraoperative Phase

• Nurse’s Role:

  • Assist surgical team, ensure patient safety.

  • Maintain sterile environment to prevent infections.

  • Monitor vital signs (heart rate, blood pressure, oxygen levels).

  • Help position patient to avoid injury, ensure access to the surgical site.

  • Document nursing interventions and intraoperative events.

Postoperative Phase

• Immediate Postoperative Care:

  • Monitor vital signs, airway, and oxygen status.

  • Manage pain according to the prescribed plan.

  • Watch for complications (hemorrhage, respiratory distress, hypothermia).

  • Inspect the surgical site for infection or drainage.

  • Ensure orientation and consciousness return.

• Discharge Instructions:

  • Provide guidance on wound care, diet, activity restrictions, and follow-ups.

  • Educate signs of complications (infection, DVT).

  • Instruct on pain management with medications.

Key Nursing Roles Across Phases

• Advocacy: Be the patient’s advocate to ensure safety.

• Safety: Prioritize safety by preventing errors, minimizing infection risks, managing complications.

• Collaboration: Work with the surgical and anesthesia teams for comprehensive care.

• Education: Provide ongoing patient and family education.

Summary

• Tissue perfusion and oxygenation are vital for cellular health; a nurse’s role is assessment, monitoring, and intervention.

• The preoperative nurse prepares the patient physically and emotionally, ensures safety, and educates for recovery.

Nursing Assessment for Tissue Perfusion

1. Vital Signs: Monitor blood pressure, heart rate, respiratory rate, temperature.

2. Peripheral Pulses: Check for strength and symmetry.

3. Capillary Refill: Assess time, should be < 3 seconds.

4. Skin and Extremities: Observe for coolness, pallor, cyanosis.

5. Urine Output: Monitor output for decreases indicating poor renal perfusion.

6. Mental Status: Watch for confusion, disorientation, drowsiness from cerebral perfusion issues.

Oxygenation Process

• Involves effective ventilation, gas exchange, oxygen transport, and cellular uptake. Tissue perfusion ensures delivery of oxygen and nutrients and waste removal. Both processes maintain organ function.

Clinical Indicators of Impaired Tissue Perfusion

• Hypotension: Suggests inadequate vital organ perfusion.

• Tachycardia: Heart compensates for low blood flow.

• Skin Symptoms: Cool, pale, or cyanotic indicators of poor blood flow.

• Capillary Refill: > 3 seconds indicates impaired circulation.

• Urine Output: Low output signifies renal perfusion issues.

• Altered Mental Status: Brain perfusion issues lead to confusion or fatigue.

• Tissue Necrosis: Extreme cases may result in cell death due to inadequate perfusion.

Cardiovascular Medications

Antihypertensive Medications

1. Diuretics: Remove excess salt and water, lowering blood volume and blood pressure.

   • Examples: Hydrochlorothiazide, Furosemide, Spironolactone.

2. Beta-blockers: Reduce heart rate and contraction force, lowering blood pressure.

   • Examples: Atenolol, Metoprolol.

3. ACE Inhibitors: Block conversion of angiotensin I to II, dilating vessels and reducing blood pressure.

   • Examples: Lisinopril, Enalapril.

4. ARBs: Block angiotensin II effects, leading to vessel dilation.

   • Examples: Losartan, Valsartan.

5. Calcium Channel Blockers: Cause vasodilation, decreasing heart rate.

   • Examples: Amlodipine, Diltiazem.

6. Alpha-blockers: Help relax and open blood vessels.

   • Examples: Doxazosin, Prazosin.

Antiplatelet and Anticoagulants

1. Antiplatelet Medications minimize clot risks.

   • Aspirin: Reduces thromboxane formation.

   • Clopidogrel: Inhibits platelet aggregation.

2. Anticoagulants prevent clot formation, treating or preventing DVT, PE, AF.

   • Warfarin (Coumadin): Inhibits vitamin K-dependent clot factors.

   • Direct Oral Anticoagulants (DOACs): Apixaban, Rivaroxaban, Dabigatran.

Other Cardiovascular Medications

1. Statins lower cholesterol, primarily LDL.

   • Examples: Atorvastatin, Simvastatin.

2. Nitrates treat angina by dilating blood vessels.

   • Examples: Nitroglycerin, Isosorbide dinitrate.

3. Heart Failure Medications assist heart function.

   • ACE inhibitors, beta-blockers, and diuretics for fluid management.

   • Digoxin: Increases contraction force, lowers heart rate.

Antiarrhythmic Medications

1. Class I Antiarrhythmics (Sodium Channel Blockers): Lidocaine, Procainamide.

2. Class II Antiarrhythmics (Beta-blockers): Metoprolol, Atenolol.

3. Class III Antiarrhythmics (Potassium Channel Blockers): Amiodarone for life-threatening arrhythmias.

4. Class IV Antiarrhythmics (Calcium Channel Blockers): Verapamil and Diltiazem.

Oxygenation Scenarios

Scenario-Based Nurse Interventions

1. COPD Patient: Administer supplemental oxygen monitoring.

2. Heart Failure: Administer diuretics to relieve fluid overload.

3. Asthma Attack: Identify acute respiratory acidosis; administer appropriate interventions.

4. Pulmonary Embolism: Prioritize oxygen and notify for anticoagulation.

5. Post-CABG Patient: Monitor for signs of tissue perfusion impairment.

6. Preoperative Care: Ensure patient is NPO and insulin management.

Answer Key for Oxygenation Scenarios

1. B) Administer supplemental oxygen.

2. B) Administer diuretics.

3. B) Acute respiratory acidosis; act accordingly.

4. A) Administer oxygen and notify physician.

5. B) Risk of impaired tissue perfusion is primary concern.

Preoperative Care Scenarios

1. Preoperative Preparation: Ensure patient education and address anxiety effectively.

2. Blood Glucose Management: Administer prescribed insulin if indicated preoperatively.

3. Patient Safety: Ensure readiness for surgery considering all preop assessments.

4. Post-Anesthesia Support: Address respiratory management needs for patients with sleep apnea.

Answer Key for Preoperative Care Scenarios

1. A) Ensure NPO status.

2. B) Administer insulin.

3. B) Notify about elevated creatinine.

4. B) Address anxiety through education.