Individuals with respiratory acidosis experience anxiety, restlessness, blurred vision and headache. In addition, they also experience shortness of breath along with lethargy and fatigue. In more advanced stages, affected individuals show signs of neurologic abnormalities characterized by delirium, asterixis, development of tremors and somnolence [7]. In severe cases, the individual can even go into a coma. Severe hypercapnia may set in which increases the cerebral blood flow and the intracranial pressure leading to the development of papillemdema [8].

• Weakness

  […] bicarb increased as well -breathing; slowed or difficult, retain CO2, late signs = cyanosis -CNS; HA, drowsy, restless, tremor, cofusion, disorientation -> COMA (cerebral vasodilation, increased bloodflow to brain) & death -increased HR, lack of energy, weakness [quizlet.com]

  Measurement of transdiaphragmatic pressure is a useful diagnostic test for documenting respiratory muscle weakness. However, it is difficult to perform and is usually carried out only in specialized pulmonary function laboratories. [emedicine.com]

  Note: if there is any problem with the patient breathing rate (too slow), alveolar sacs (damaged), or diaphragm (weak) the patient can experience respiratory acidosis. * Main cause of respiratory acidosis is bradypnea (slow respiratory rate When this [registerednursern.com]

  Hypoventilation can result from neurologic disorders (eg, stroke) or medications (eg, opiates) that affect the central nervous system respiratory center, respiratory muscle weakness (eg, myasthenia gravis, Guillain-Barré syndrome) or chest wall deformity [ime.acponline.org]

• Fatigue

  Consequently, it can not be confirmed that any tw, P mo change was only due to diaphragmatic fatigue, i.e. would have been uninfluenced by fatigue of accessory inspiratory muscles. [erj.ersjournals.com]

  Physical activity becomes difficult because of fatigue and shortness of breath, and movements, particularly fine movements of the hands, can also become impaired. [livestrong.com]

  Hypercapnia typically occurs late in the disease process with severe pulmonary disease or when respiratory muscles fatigue. (See also Pediatric Respiratory Acidosis, Metabolic Acidosis, and Pediatric Metabolic Acidosis .) [emedicine.com]

  Hypercapnia only occurs if severe disease or respiratory muscle fatigue occurs. Metabolism rapidly generates a large quantity of volatile acid (H2CO3) and nonvolatile acid. [en.wikipedia.org]

• Excessive Daytime Sleepiness

  Slowly developing, stable respiratory acidosis (as in COPD [chronic obstructive pulmonary disease]) may be well tolerated, but patients may have memory loss, sleep disturbances, excessive daytime sleepiness, and personality changes. [msdmanuals.com]

  Following non-specific symptoms may be seen in patients suffering from respiratory acidosis: Anxiety Breathlessness Disturbed sleep Excessive daytime sleepiness Hallucinations Confusion Dullness Wheezing Increased chest expansion Decreased breath sounds [healthhype.com]

• Asymptomatic

  Respiratory acidosis can be acute or chronic; the chronic form is asymptomatic, but the acute, or worsening, form causes headache, confusion, and drowsiness. Signs include tremor, myoclonic jerks, and asterixis. [msdmanuals.com]

  Chronic Respiratory Acidosis: This type of Respiratory Acidosis develops over time and is relatively asymptomatic. [epainassist.com]

• Pallor

  loss of coordination (chronic), to stupor CIRCULATION May exhibit: Low BP/ hypotension with bounding pulses, pinkish color, warm skin (reflects vasodilation of severe acidosis) Tachycardia, irregular pulse (other/various dysrhythmias) Diaphoresis, pallor [nurseslabs.com]

• Cough

  […] are currently in the system (such as; anesthetics, hypnotics, opioids, sedatives) EKG; hyperkalemia could cause arrhythmias improve respiratory ventilation via: -mechanical ventilation -bronchodilators, antibiotics, anticoagulants -pulmonary hygiene; coughing [quizlet.com]

  Symptoms Symptoms of the diseases that cause respiratory acidosis are usually noticeable, and may include shortness of breath, easy fatigue, chronic cough, or wheezing. [medical-dictionary-search-engines.com]

  If you are visiting at high altitude -- especially above 8,000 feet -- seek immediate medical care if you notice any shortness of breath, headache, insomnia, fluid retention or a cough. [livestrong.com]

  Emphysema & COPD) Signs and Symptoms of Respiratory Acidosis Major neuro changes: Confused, very drowsy, and reports a headache respiration rate less than 12 low blood pressure Nursing Interventions for Respiratory Acidosis Administer oxygen encourage coughing [registerednursern.com]

  Encourage and assist with deep-breathing exercises, turning, and coughing. Suction as necessary. Provide airway adjunct as indicated. Place in semi-Fowler’s position. [nurseslabs.com]

• Choking

  […] dystrophy ) scoliosis Some common causes of the acute form are: lung disorders (COPD, emphysema, asthma, pneumonia) conditions that affect the rate of breathing muscle weakness that affects breathing or taking a deep breath obstructed airways (due to choking [healthline.com]

• Asterixis

  Signs include gait disturbance, tremor, blunted deep tendon reflexes, myoclonic jerks, asterixis, and papilledema. [msdmanuals.com]

  Respiratory acidosis may manifest as hypercapnic encephalopathy, a clinical syndrome that initially can present as irritability, headache, mental cloudiness, apathy, confusion, anxiety, and restlessness and can progress to asterixis, transient psychosis [ime.acponline.org]

  […] wall deformity Tension pneumothorax, pleural effusion Upper airway obstruction Equipment Increased dead space, improper connection Obstructive pulmonary disease (chronic) COPD, asthma, pneumonia Clinical Vasodilation, sweaty, tachycardic, mydriasis, asterixis [lifeinthefastlane.com]

• Hypertension

  An 87-year-old female, with a history of hypertension controlled with hydrochlorothiazide, was scheduled for excision of a cystic mass of the left lobe of the thyroid. [ncbi.nlm.nih.gov]

  In long-term, this can give rise to problems like: Pulmonary hypertension Cor pulmonale Right ventricular failure The apneas and hypopneas can result in impaired sleep quality as well as cerebral vasodilation which can cause: Daytime fatigue Morning headaches [hxbenefit.com]

  Pulmonary hypertension -- high blood pressure within the lungs -- can result from long-term untreated hypoxemia. [livestrong.com]

  Chronic hypoxemia can also cause narrowing of pulmonary arteries, which may increase blood pressure in the arteries of the lungs (pulmonary hypertension). This may result in heart failure. [healthhype.com]

• Tachycardia

  Tachycardia develops early because the sympathetic nervous system is stimulated, resulting in the release of catecholamines, epinephrine, and norepinephrine, in an attempt to increase oxygen delivery to the tissues. [nurseslabs.com]

  […] initial signs; muscle twitching, tremors, seizures, and coma can ensue; rapid respirations initially and then decreased due to adaptation; vasodilation due to acidosis (CO2 is a vasodilator), therefore the skin might be pink, unless there is hypoxemia; tachycardia [m2hnursing.com]

  See also metabolic alkalosis, respiratory alkalosis. observations Some common signs and symptoms of respiratory acidosis are headache, dyspnea, fine tremors, tachycardia, hypertension, and vasodilation. [medical-dictionary.thefreedictionary.com]

• Hypotension

  We conclude that rapid correction of respiratory acidosis, especially in the setting of hypotension, can lead to life-threatening hypokalemia. [ncbi.nlm.nih.gov]

  ACTIVITY/REST May report: Fatigue, mild to profound May exhibit: Generalized weakness, ataxia/staggering, loss of coordination (chronic), to stupor CIRCULATION May exhibit: Low BP/ hypotension with bounding pulses, pinkish color, warm skin (reflects vasodilation [nurseslabs.com]

  CAUSES… Hypoxemia or tissue hypoxia Decreased inspired O2 tension/High altitude Bacterial or viral pneumonia Aspiration of food, foreign body, or vomitus Larygospasm, Drowning Cyanotic heart disease, Severe ciurculatory failure Severe anemia,Hypotension [slideshare.net]

• Muscle Weakness

  Measurement of transdiaphragmatic pressure is a useful diagnostic test for documenting respiratory muscle weakness. However, it is difficult to perform and is usually carried out only in specialized pulmonary function laboratories. [emedicine.com]

  Hypoventilation can result from neurologic disorders (eg, stroke) or medications (eg, opiates) that affect the central nervous system respiratory center, respiratory muscle weakness (eg, myasthenia gravis, Guillain-Barré syndrome) or chest wall deformity [ime.acponline.org]

• Confusion

  Acute (or acutely worsening chronic) respiratory acidosis causes headache, confusion, anxiety, drowsiness, and stupor (CO2 narcosis). [msdmanuals.com]

  Nursing Diagnosis The following are the possible nursing diagnosis for Respiratory Acidosis: Impaired Gas Exchange Ineffective Breathing Pattern Ineffective Tissue Perfusion Acute Confusion Risk for Injury Nursing Priorities Achieve homeostasis. [nurseslabs.com]

  When respiratory acidosis becomes severe, confusion, irritability, or lethargy may be apparent. [medical-dictionary-search-engines.com]

• Headache

  Acute (or acutely worsening chronic) respiratory acidosis causes headache, confusion, anxiety, drowsiness, and stupor (CO2 narcosis). [msdmanuals.com]

  If you are visiting at high altitude -- especially above 8,000 feet -- seek immediate medical care if you notice any shortness of breath, headache, insomnia, fluid retention or a cough. [livestrong.com]

  Respiratory acidosis may manifest as hypercapnic encephalopathy, a clinical syndrome that initially can present as irritability, headache, mental cloudiness, apathy, confusion, anxiety, and restlessness and can progress to asterixis, transient psychosis [ime.acponline.org]

• Tremor

  Signs include gait disturbance, tremor, blunted deep tendon reflexes, myoclonic jerks, asterixis, and papilledema. [msdmanuals.com]

  In more advanced stages, affected individuals show signs of neurologic abnormalities characterized by delirium, asterixis, development of tremors and somnolence. In severe cases, the individual can even go into a coma. [symptoma.com]

  Chest wall trauma Pulmonary edema Atelectasis Pneumothorax Drug Overdose Pneumonia Guillain-Barre syndrome Complications Shock Cardiac Arrest Signs and Symptoms CNS disturbances: restlessness, confusion, and apprehension to somnolence with fine flapping tremor [nurseslabs.com]

• Seizure

  A rapid decline of the PaCO2 can lead to respiratory alkalosis with seizures and death. Check for hypoxemia and hypercapnia when administering oxygen. [m2hnursing.com]

  […] acute anxiety. think of the things that would cause a person to breathe very rapidly and cause large losses of carbon dioxide. symptoms are: ph elevated above 7.45 and pco2 below 35mmhg rapid, deep breathing hyper ventilation agitation paresthesias seizures [allnurses.com]

  […] corrected slowly (eg, over several hours or more), because too-rapid Pco2 lowering can cause a posthypercapnic “overshoot” alkalosis when the underlying compensatory hyperbicarbonatemia becomes unmasked; the abrupt rise in CNS pH that results can lead to seizures [msdmanuals.com]

  The mental status of the patient might be depressed due to higher levels of Pa CO 2 and may have signs of myoclonus, asterixis and seizures. [hxbenefit.com]

• Stupor

  Clinical features Often combination of hypercapnia and hypoxia Most effects are neurologic, ranging from anxiety and confusion to stupor to coma. [clinicaladvisor.com]

  Acute (or acutely worsening chronic) respiratory acidosis causes headache, confusion, anxiety, drowsiness, and stupor (CO2 narcosis). [msdmanuals.com]

  ACTIVITY/REST May report: Fatigue, mild to profound May exhibit: Generalized weakness, ataxia/staggering, loss of coordination (chronic), to stupor CIRCULATION May exhibit: Low BP/ hypotension with bounding pulses, pinkish color, warm skin (reflects vasodilation [nurseslabs.com]

The following diagnostic tools are employed for evaluating the condition of respiratory acidosis:

• Laboratory tests: Measuring the arterial blood gas forms the basis of the diagnosis. This is required to measure the levels of carbon dioxide and oxygen in the blood. Following this, serum bicarbonate levels should also be evaluated along with complete blood count and thyroid studies [9].
• Radiography: Chest x – ray should be carried out to rule out pulmonary disease. Fluoroscopy may also be required in addition to chest radiographs to diagnose diaphragmatic paralysis.
• Imaging studies: Imaging studies such as CT (computerized tomography) scan and MRI (Magnetic resonance imaging) are required when radiographs do not provide conclusive results. CT scan provides more useful results for diagnosing pulmonary disease. MRI is done when CT scan results are inconclusive.
• Pulmonary lung function tests: These are done to diagnose the condition of chronic obstructive pulmonary disease.

• Hypercapnia

  Respiratory acidosis is an expected part of planned mechanical hypoventilation in ICU (permissive hypercapnia). [clinicaladvisor.com]

  Hypercapnia and respiratory acidosis ensue when impairment in ventilation occurs and the removal of carbon dioxide by the respiratory system is less than the production of carbon dioxide in the tissues. [emedicine.com]

  Moderate hypercapnia had no effect on these parameters. [ncbi.nlm.nih.gov]

• Bicarbonate Increased

  Measurement of the serum bicarbonate permits definitive diagnosis: acute respiratory acidosis: serum bicarbonate increases by 1 mmol/l for each 10 mmHg (or 1.33kPa) increase in PaCO2 chronic respiratory acidosis: serum bicarbonate increases by 3.5 mmol [gpnotebook.co.uk]

  The Copenhagen school of ABG analysis goes to some considerable lengths to separate the physicochemical effects of increasing PaCO 2 on bicarbonate from the role of bicarbonate as a buffer for metabolic disorders. [derangedphysiology.com]

  The increase in plasma [HCO3] results in an increase in amount of bicarbonate filtered in the kidney and this amount increases as plasma bicarbonate continues to increase. [anaesthesiamcq.com]

• Chloride Decreased

  Serum chloride: Decreased. Serum calcium: Increased. Lactic acid: May be elevated. Urinalysis: Urine pH decreased. Other screening tests: As indicated by underlying illness/condition to determine underlying cause. [nurseslabs.com]

Treatment of acute respiratory acidosis involves preliminary correction of the underlying condition. The airway should be cleared so that the volatile fractions can get gradually excreted.

Chronic respiratory acidosis can be treated by clearing the airway passage and managing underlying diseases.

Bronchodilators may have to be administered for expanding the air passage. In addition, antibiotics will also be required for treating infections. These are given along with diuretics in order to decrease the pressure on the heart and lungs and corticosteroids are given for reducing the inflammation. In severe cases, the individuals would have to be put on ventilator [10].

The prognostic factor for individuals with respiratory acidosis largely depends on the underlying causative factor and the severity of the disease. If the underlying disease can be successfully treated, then the condition of respiratory acidosis can be corrected as well. In such cases, the prognosis of the condition is pretty good [6].

Sudden ventilation failure is the major cause of acute respiratory acidosis. This type of condition occurs due to depression that occurs in the central respiratory region by cerebral diseases. In addition, drugs, obstruction of the airways, asthma and chronic obstructive pulmonary disease can also favor ventilation failure causing acute respiratory acidosis. Certain other disease conditions such as myasthenia gravis, muscular dystrophy and amyotrophic lateral sclerosis can also lead to acute respiratory failure [2].

Chronic respiratory acidosis occurs as a secondary phenomenon to other disease conditions such as Pickwickian syndrome, various neuromuscular diseases and ventilator defects [3].

The exact prevalence of respiratory acidosis is unknown. However, it has been reported that patients with chronic obstructive pulmonary disease are prone to develop respiratory acidosis. In a one year prospective study carried out during the years 1997 -1998, the relationship between respiratory acidosis and oxygenation was explained. The results revealed that of 983 patients that were admitted to the hospital, 972 suffered from respiratory acidosis. Such patients require non-invasive ventilation in order to correct the condition of acidosis. From the available data, it can be estimated that of the 90 patients that would be admitted to UK hospitals every year, 72 cases would be that of respiratory acidosis [4].

Under normal physiological conditions, metabolic processes generate huge amounts of volatile as well as nonvolatile acid. In addition to this phenomenon, metabolism of fats and carbohydrates also produces large amounts of carbon dioxide.

The carbon dioxide combines with water leading to the formation of carbonic acid. If the lungs function in the normal fashion, then the carbonic acid is readily excreted through the process of ventilation. Such a phenomenon, therefore does not favor the accumulation of acid. Conditions or processes that interfere with the normal ventilation process can disturb the excretion of volatile fraction which in turn would cause acid accumulation in the body [5].

Avoiding smoking can go a long way in preventing the onset of lung disorders, which may in turn pave way for development of respiratory acidosis. Obesity induced respiratory acidosis can be prevented by keeping weight under check. Individuals are also advised against taking medications that induce sedation; moreover, they should never be combined with alcohol.

Respiratory acidosis can be either acute or chronic in nature. In this type of acidosis, there is an excessive buildup of carbon dioxide in the body due to the inability of the lungs to remove the excess carbon dioxide. Respiratory acidosis is defined by an arterial pH of less than 7.36 and an increase in pCO2 and HCO3- [1]. It is an emergency situation, requiring prompt treatment. 

Respiratory acidosis is a condition in which there is is increase in the carbon dioxide concentration in body due to diseases affecting the lungs. Underlying disease conditions such as asthma, chronic obstructive lung disease, diseases of chest, obesity and certain drugs favor the development of respiratory acidosis. Symptoms of respiratory acidosis include breathlessness, fatigue, lethargy and sleepiness. In severe cases, individuals would also experience neurologic symptoms such as delirium, confusion, somnolence and onset of tremors. Treating the underlying disease condition forms the basis of the treatment regime.

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