Respiratory Management of the Surgical Patient Flashcards
Pulmonary Ventilation
- Inspiration occurs due to the contraction of muscle that cause a negative intrathoracic pressureFlow is generated due to pressure gradient from atmosphere to alveoli
- Expiration is passive after intrathoracic (specifically intra-alveolar) pressure is greater than the atmosphere
Compliance
Extent to which lungs expand per unit increase in transpulmonary pressure or stretchiness
Bronchospasm
- Airways (bronchial tubes) go into spasm and contract. This makes it hard to breathe
Clinical manifestations
- Wheeze
- Tachypnoea
- Hypercapnia
- Histamine release causing mast cells degranulation
- Reflex bronchoconstriction due to tracheal stimulation from secretions
Treatments
- Remove cause, beta 2 agonist
Dyspnoea
- Subjective sensation of uncomfortable breathing
- Common symptom of respiratory disease
- V/Q mismatches
- Lung diseases
- May related to stretch receptor
- Paroxysmal nocturnal dyspnoea (sudden attack) - acute shortness of breath
- Posture-induced dyspnoea
- Orthopnoea: lying position - characteristic of heart failure
Atelectasis
- complete or partial collapse of the entire lung or area (lobe) of the lung. It occurs when the tiny air sacs (alveoli) within the lung become deflated or possibly filled with alveolar fluid.
- one of the most common breathing (respiratory) complications after surgery
- Pathophysiology
§ Decreased diaphragmatic expansion - lung compliance
§ Retained airway secretion
§ Postoperative pain - Clinical manifestation
§ Can be asymptomatic, minor to severe symptoms, dependent on magnitude of lung collapse
§ Cough and dyspnoea common
Hypoxaemia, tachycardia, hypotension or pneumonia
Treatment of atelectasis
- Early mobilisation and incentive spirometry
- nebulised bronchodilators
- positive pressure ventilation
- oxygen and antibiotics
Hypoxaemia/Hypoxia
Low blood or tissue oxygen level
- common condition in postop
Causation
- hypoventilation
- V-Q mismatches
- decreased alveolar diffusion
Pathophysiology
- depression of minute ventilation/CO2 relationship
- shunting of gas volume from under ventilated diffusion
- decrease in gas volume to under perfused alveoli
Clinical Manifestations
- tachypnoea
- dysponea
- cognitive changes
- vasodilation and hypotension
- cyanosis and coma
Pleural effusion
- build-up of excess fluid between the layers of the pleura outside the lungs
- The pleura are thin membranes that line the lungs and the inside of the chest cavity and act to lubricate and facilitate breathing
- Causation
- Imbalance between fluid production and removal
- Inadequate lung expansion
- Disruption of pleural membrane
Clinical manifestations
- Cough, dyspnoea, pleural friction rub, decreased breath sounds
Diagnosis
- Clinical examination - Chest x ray
Treatment - Often nothing as resolves once patient is active - Chest physiotherapy - Oxygen therapy of severe - Can need drainage: thoracentesis □ Drainage is removal of fluids
Pneumonia
Infection of the lungs, alveoli are filled with fluid or pus making it harder to breathe
Difficult to diagnose because many other conditions similar - atelectasis, pulmonary oedema
Respiratory acidosis
Condition that occurs when the lungs can’t remove enough of the carbon dioxide (CO2) produced by the body
PaCO2 + HCO3 elevated
Metabolic acidosis
Electrolyte disorder characterized by an imbalance in the body’s acid-base balance. Metabolic acidosis has three main root causes: increased acid production, loss of bicarbonate, and a reduced ability of the kidneys to excrete excess acids
PaCO2 + HCO3 decreased
Respiratory alkalosis
occurs when you breathe too fast or too deep and carbon dioxide levels drop too low.
PaCO2 + HCO3 decreased
Metabolic alkalosis
Occurs when your blood becomes overly alkalin
PaCO2 + HCO3 increased
Pulse Oximetry
Relative measure of percentage of bound oxygen to haemoglobin
