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].

• 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]

• Sepsis

  "Sepsis and therapeutic hypercapnia: sailing too close to the wind?". Anesthesiology. vol. 112. 2010. pp. 462-472. Copyright © 2017, 2013 Decision Support in Medicine, LLC. All rights reserved. [clinicaladvisor.com]

  It may be caused by severe illness or sepsis (bacteria in the bloodstream) A disorder characterized by abnormally high acidity (high hydrogen-ion concentration) of the blood and other body tissues A pathologic condition of acid accumulation or depletion [icd9data.com]

  […] opiates, sedatives, anaesthetics) neuromuscular disorders lung or chest wall defects airway obstruction inadequate mechanical ventilation Over-production of CO2 -> hypercatabolic disorders Malignant hyperthermia Thyroid storm Phaeochromocytoma Early sepsis [lifeinthefastlane.com]

  PATIENTS: A convenience cohort of patients with severe sepsis or septic shock. [crashingpatient.com]

  […] significant rebreathing of expired carbon dioxide Patients who are paralysed and on controlled ventilation cannot increase their alveolar ventilation to excrete any increased amounts of CO 2 produced by the body (eg in hypercatabolic states such as sepsis [anaesthesiamcq.com]

• Anorexia

  OBJECTIVE: To examine the effect of malnutrition due to anorexia nervosa (AN) on venous blood gases of adolescents with AN hospitalized for medical stabilization. [ncbi.nlm.nih.gov]

  Anaerobic metabolism; Drug overdose (e.g.salicylates); Renal failure; Diabetic ketoacidosis Manifestations: headache and lethargy are early symptoms; warm flushed skin; seizures; mental confusion; muscle twitching; agitation; coma (severe acidosis); anorexia [m2hnursing.com]

  Cushing’s Disease | 6 Care Plans Diabetes Mellitus Type 1 (Juvenile Diabetes) | 4 Care Plans Diabetes Mellitus Type 2 | 13+ Care Plans Diabetic Ketoacidosis (DKA) and Hyperglycemic Hyperosmolar Nonketotic Syndrome (HHNS) | 4 Care Plans Eating Disorders: Anorexia [nurseslabs.com]

  Neurological: “hypercapnic encephalopathy”include 1. irritability, inability to concentrate, 2. headache, anorexia, 3. apathy, confusion, combativeness, hallucinations, delirium, 4. transient psychosis, progressive narcosis, and coma. 5. [slideshare.net]

• 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]

• Congestive Heart Failure

  Hypoxemia (caused by pulmonary disease, high altitudes, or congestive heart failure), hypermetabolic conditions (fever or anemia), gram-negative sepsis, hysteria, or cirrhosis of the liver can stimulate hyperventilation. [m2hnursing.com]

• Nausea

  Nausea and vomiting might be present. Increased blood pH; Decreased PaCO2; Normal HCO3 or decreased if compensation is occurring. Nursing Interventions: Assess the clinical symptoms, health history, and lab results. [m2hnursing.com]

  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, and cyanosis (late stage) FOOD/FLUID May report: Nausea [nurseslabs.com]

  "Give someone who has faith in you a placebo and call it a hair growing pill, anti-nausea pill or whatever, and you will be amazed at how many respond to your therapy. " – Bernie Siegel Treating Acid-base Disturbances. [acid-base.com]

• Heart Failure

  Hypoxemia (caused by pulmonary disease, high altitudes, or congestive heart failure), hypermetabolic conditions (fever or anemia), gram-negative sepsis, hysteria, or cirrhosis of the liver can stimulate hyperventilation. [m2hnursing.com]

  Lactic acidosis (over-production of lactic acid that occurs from heart failure -> hypoxia resulting in anaerobic glucose metabolism). 4. [quizlet.com]

  This may result in heart failure. Sleep quality is often disturbed in patients with respiratory acidosis, which causes morning headaches, sleepiness, and daytime fatigue. [healthhype.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]

• 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]

• Myopathy

  (at or above C4 level) High central neural blockade Poliomyelitis Tetanus Cardiac arrest with cerebral hypoxia Nerve or Muscle Disorders Guillain-Barre syndrome Myasthenia gravis Muscle relaxant drugs Toxins eg organophosphates, snake venom Various myopathies [anaesthesiamcq.com]

  Other probable causes of the disorder include problems like: Tetanus Aspiration Poliomyelitis Pneumothorax Laryngospasm Bronchospasm Pulmonary edema Various myopathies Respiratory alkalosis Restrictive lung disease Malignant Hyperthermia Upper Airway [hxbenefit.com]

  […] obstruction Aspiration of foreign body or vomitus Laryngospasm or angioedema Obstructive sleep apnea Neuromuscular impairment High spinal cord injury, Guillain-Barre syndrome Status epilepticus, Botulism, tetanus Crisis in myathenia gravis Hypokalemic myopathy [slideshare.net]

• 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]

• Stroke

  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]

  Feet Carpal Tunnel Syndrome Diet and Nutrition Emergency Supplies Fall Prevention Fibromyalgia Fitness and Health Hearing Loss Home Health Care and Safety Industrial and Public Health Safety Occupational Health Safety Sight Impaired Sleeping - COPD Stroke [activeforever.com]

  Defects of the brainstem respiratory centers may occur due to ingestion of certain drugs such as opiates or a stroke. Obstruction of airways may result from causes of airway obstruction or in contexts of asthma exacerbation. [pathwaymedicine.org]

  However, central hypoventilation (eg, caused by CNS disturbance such as stroke, head injury or brain tumour) causes respiratory acidosis. In general, the kidneys compensate for respiratory causes and the lungs compensate for metabolic causes. [patient.info]

• Paresthesia

  […] altitudes and with 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 [allnurses.com]

  Clinical Manifestations: confusion, dizziness, paresthesias (tingling of extremities), seizures and coma; tachypnea (deep and rapid respirations) causes respiratory alkalosis. Nausea and vomiting might be present. [m2hnursing.com]

  […] airway obstruction Chronic respiratory acidosis (increased bicarbonate) COPD kyphoscoliosis Obesity hypoventilation syndromes End stage restrictive pulmonary disease Respiratory Alkalosis Respiratory alkalosis Acute hyperventilation (Light headedness, paresthesias [stritch.luc.edu]

  Neurological: Rapid decrements in PaCO2 to half the normal values or lower are typically accompanied by 1. paresthesias of the extremities, 2. chest discomfort, 3. circumoral numbness, lightheadedness, 4. confusion, and infrequently, tetany or generalized [slideshare.net]

• Tingling

  […] 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 confusion hypo kalemia lightheadedness dizziness tingling [allnurses.com]

  Clinical Manifestations: confusion, dizziness, paresthesias (tingling of extremities), seizures and coma; tachypnea (deep and rapid respirations) causes respiratory alkalosis. Nausea and vomiting might be present. [m2hnursing.com]

  […] acidosis (increased bicarbonate) COPD kyphoscoliosis Obesity hypoventilation syndromes End stage restrictive pulmonary disease Respiratory Alkalosis Respiratory alkalosis Acute hyperventilation (Light headedness, paresthesias, circumvoral numbness, tingling [stritch.luc.edu]

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]

• Hypochloremia

  Given that the renal capacity for excreting the excess of bicarbonate is great, MAlk only perpetuates when certain circumstances coexist, such as a reduction in effective volemia, hypochloremia, hypokalemia or hyperaldosteronism, in which the renal reabsorption [archbronconeumol.org]

  […] see also Disease electrolyte (balance) E87.8 ICD-10-CM Diagnosis Code E87.8 Other disorders of electrolyte and fluid balance, not elsewhere classified 2016 2017 2018 2019 Billable/Specific Code Applicable To Electrolyte imbalance NOS Hyperchloremia Hypochloremia [icd10data.com]

  The renal response to chronic hypercapnia includes a transient increase in chloride excretion and generation of hypochloremia. [slideshare.net]

• 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]

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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