Nutrition and Pulmonary Function

• Nutritional status and pulmonary function are interdependent

Nutrition and Pulmonary Function

• Carbohydrates, protein, and lipids are metabolized using oxygen, producing carbon dioxide.
• Malnutrition can result from pulmonary disorders and worsen pulmonary status.
• Weight loss and underweight status independently correlate with poor prognoses in those with COPD.

Normal Anatomy and Physiology

• The respiratory system includes the upper and lower respiratory tracts.
• Bronchi carries air to the lungs.
• Alveoli, small air sacs, facilitates gas exchange.
• Capillaries are responsible for oxygen and carbon dioxide exchange.
• Alveolar epithelium consists of type 1 and type 2 cells.

Gas Exchange

• Lungs enable the body to obtain oxygen for cellular metabolism and remove carbon dioxide.
• Lungs synthesize surfactant and regulate acid-base balance.

Respiratory System: Protection and Maintenance

• Lung tissue defends against infection and toxins.
• Inhaled particles are trapped by a sticky mucus, keeping the airway moist.
• Cilia move mucus and unwanted cells upward to be expectorated or swallowed.
• Alveoli goblet cells engulf and destroy bacteria.

Mucociliary Transport System

• Cilia, located in the lumen of the bronchus, work to transport mucus and dust particles to the trachea for removal.

Measures of Pulmonary Function

• Percussion and auscultation aid the detection of pulmonary consolidation, pleural effusion, atelectasis, and airway obstruction.
• Pulmonary function tests include pulse oximetry and spirometry.
• Spirometry measures forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1); >70% is considered normal.
• ABG evaluation measures pulmonary status.
• Normal oxygen saturation is 95-100%.
• Supplemental O2 is needed if saturation is less than 89%.

Malnutrition Impact

• Malnutrition has adverse clinical outcomes, reduces strength/endurance of respiratory muscles, and reduces the alveoli, bronchioles, and capillaries.
• Continued malnutrition increases infection risk.

Chronic Obstructive Pulmonary Disease (COPD)

• COPD is a progressive disease that limits airflow due to inflammation of bronchial tubes (bronchitis) or destruction of alveoli (emphysema).

Classifications of COPD Severity

• GOLD 1: Mild, FEV₁ ≥ 80% predicted
• GOLD 2: Moderate, 50% ≤ FEV₁ < 80% predicted
• GOLD 3: Severe, 30% ≤ FEV₁ < 50% predicted
• GOLD 4: Very Severe, FEV₁ < 30% predicted
• F E V₁ = forced expiratory volume in 1 second; FVC = forced vital capacity.

COPD: Etiology and Diagnosis

• Chronic bronchitis is primarily caused by cigarette smoking or secondhand smoke
• Chronic bronchitis results in a productive cough and shortness of breath for 3 months each year for 2 or more years, and destruction of cilia in the lungs.
• Emphysema develops gradually due to smoke exposure.
• It is characterized by ongoing inflammation causing oxidative stress and leads to damaged alveoli, reducing the amount of oxygen in the blood.

Chronic Bronchitis: Pathophysiology

• COPD involves a generalized inflammatory response to repeat exposure to pollutants.
• It leads to decreased cilia function, increased phagocytosis, suppressed Immunoglobulin A, edema of the bronchioles, thickened airways, and hyperplastic mucus glands.
• This results in inability to increase the work of breathing and overcome the symptoms

Chronic Bronchitis: Clinical Manifestations

• Clinical manifestations of chronic bronchitis includes decreased pulmonary function, dyspnea, hypoxemia, hypercapnia, cyanosis, clubbing, and secondary polycythemia. Quality of life diminishes and there will be a requirement for supplemental oxygen, and may result in cor pulmonale.

Emphysema: Pathophysiology

• Emphysema involves lung tissue destruction, loss of surface area, decreased surfactant, bronchioles collapse during exhalation and hyperinflation.

Emphysema: Clinical Manifestations

• Clinical manifestations of emphysema involves decreased FEV, dyspnea, orthopnea, hypercapnia, respiratory acidosis, barrel chest, as well as extreme fatigue and exhaustion.

COPD: Treatment

• Treatment encompasses lifestyle changes, smoking cessation, proper nutrition, exercise as tolerated, pulmonary rehabilitation, pharmacological therapies(bronchodilators and steroids).

COPD: Malnutrition

• Weight LBM losses are found in more than 25% of COPD patients with severe lung disease
• Malnutrition may not be noticeable through calculation of weight loss but instead by observation of LBM losses
• Clinical causes of weight loss/LBM loss includes symptoms such as: anorexia, difficulty chewing and swallowing, increased resting energy expenditure, as well as medications.

Nutrition Therapy for COPD

• Nutrition assessment is needed, along with the identification of malutrition if present
• Complete nutrition assessment is required, including: anthropometric measurements and NFPE.
• People with emphysema tend to be underweight while people with Bronchitis tend to be of normal or above normal weight
• Evaluate for edema as this may mask weight or LBM losses
• Food and nutrition-related history, and medication use must be accounted for
• Physical activity and functional status must also be assessed.

Nutrition Diagnosis for COPD

• Nutrition diagnosis includes inadequate oral intake, malnutrition, drug-nutrient interactions, difficulty swallowing, unintended weight loss, increased energy expenditure, increased nutrient needs, inability to manage self-care, and food and nutrition-related knowledge deficit.

Nutrition Therapy for COPD: Treatment Needs

• Increased energy and nutrient is required due to the increased work of breathing.
• REE x AF 1.2 - 1.5 is a guide for patients admitted to the hospital
• 1.2-1.7 g/kg protein
• 30 kcal/kg of body weight can be used for weight maintenance with about 20% of total kilocalories from protein.
• For those trying to gain weight, needs are significantly higher with needs up to or > 45 kcals/kg

Nutrition Therapy for COPD: Intervention

• Food and/or nutrient delivery strategies.
• Integrating physical exercise into nutrition care.
• Exercise is an equally important component of treatment.
• Pulmonary rehab in conjunction with nutrition has shown the best overall effect on stable patients.

Antioxidants

• Antioxidant intake is crutial for treatment of COPD
• Cigarette smoke increases the level of oxidants in the lungs, resulting in a decrease of antioxidants which then promotes oxidative stress and the destruction of alveoli
• Oxidative stress has also been linked to inflammation of the airways of the lungs, something that's common in COPD patients.
• Recommendations include A, D, E and Vitamin C, Coenzyme Q and resveratol

Planning Nutrition Interventions for Individuals with COPD

• It is important to use patient preference to guide food suggestions, limited evidence supports a specific macronutrient mix but the Mediterranean diet pattern may guide food choices
• Medical food supplements can be used as a variety of high-calorie, high-protein supplements to increase overall nutritional intake.

Monitoring and Evaluation

• Monitoring and evaluation is key for these factors: Oral intake, nursing reports, patient and/or family report, anthropometrics, weekly dry weights,functionality, swallowing, fatigue, and early satiety

Cystic Fibrosis (CF)

• Inherited disorder characterized by abnormally thick mucus secretions from epithelial surfaces with approximately 1000 new cases are diagnosed each year and one in 30 Americans is a carrier
• Etiology:Abnormal cystic fibrosis transmembrane conductance regulator gene (CFTR) proteins

Cystic Fibrosis: Pathophysiology

• Increased mucus production in glands which leads to eventual obstruction of glands and ducts. This can cause: Chronic respiratory symptoms, CF-related diabetes, malabsorption, cirrhosis of the liver with portal hypertension, dehydration and electrolyte imbalances.

Cystic Fibrosis: Medical Diagnosis

• Diagnosis can be performed via Newborn screening for CF which consists of serum tests- performed in all 50 states.
• One such test is the Sweat Chloride Test and the Fecal Elastase Test

Nutrition Implications of Cystic Fibrosis

• Nutritional implications are key in treatment

Cystic Fibrosis: Nutrition Assessment and Diagnosis

• Assessment must be done via anthropometric measurements as well as biochemical and medical tests
• Nutrition diagnosis includes inadequate oral intake, inadequate energy intake, increased energy needs, altered GI function, unintended weight loss, and increased nutrient needs

Cystic Fibrosis: Nutrition Therapy

• Adequate amounts of calories must be given to encourage normal growth patterns that is based on weight gain at or above 50% in BMI testing
• Higher fat intake should occur ranging (35-40% kcal).

Cystic Fibrosis: Supplementation

• Fortification of breast milk is usually necessary to meet kcal, protein and vitamin/mineral needs

CF : Dietary Guidelines

• While families need to be counseled on appropriate intakes and supplements this needs to be taught to the patient as well.
• 5-10 years old is when patients are at the highest risk for decreased growth rate
• 11-18 years is the highest rate of growth
• Nutritional needs are high in times of exacerbation
• Regular counseling regarding nutritional needs is necessary to maintain optimal health

CF: Monitoring and Evaluation

• Monitoring includes anthropometrics to ensure appropriate growth for age, with a goal of >50th percentile for BMI
• Lab Monitoring to check Fat Soluble Vitamins and Electrolytes
• Check for malabsorption Monitoring of stools and adjustment of pancreatic enzymes is also crucial

Respiratory Failure

• Can be caused by decreased function of the lungs and can occur due to direct injury such as Pneumonia as well as through indirect injuries like Sepsis
• Decreased function of the lungs causing difficulty in meeting oxygen needs that requires action to be taken

Nutrition Therapy for Respiratory Failure

• Needs vary widely depending on the age, prior nutritional status, and underlying disease process
• Often, patients are hypermetabolic and can still have a limited NFPE

Respiratory Failure : Nuutrient Needs

• Total caloric requirements can be either estimated using a predictive equation, kcals/kg or directly measured using indirect calorimetry.
• Typical laboratory assessments for nutrition support monitoring should be followed, especially Serum phosphorus.

Nutrition Needs in Mechanical Ventilation

• ASPEN recognizes that REE may be greater in mechanically ventilated patients.
• The following is recommended for non-obese patients: predictive equations with higher activity/stress factors •For standard patients: 25-30 kcals/kg and protein: 1.2 - 2
• Obese patients:•Predictive equations that account for age and obesity levels • Hypocaloric protein sparing feeds with 2-2.5 gms/kg of IBW

Gastric Residual Volume (GRV)

• Gastric Residual Volume acts as an indicator of Tolerance for TF.

Addressing Tube Feeding Intolerance (GRV)

• Correct positioning of the bed, prescribe promotility agents, change tube feeds if needed and post pyloric feeds