Respiratory Compromise Types

Respiratory failure occurs when the respiratory system fails to maintain gas exchange, resulting in hypoxia or hypercapnia. It is classified according to blood gases values:

  • Type 1 Respiratory Failure (hypoxemic): is associated with damage to lung tissue which prevents adequate oxygenation of the blood.  However, the remaining normal lung is still sufficient to excrete carbon dioxide. This results in low oxygen, and normal or low carbon dioxide levels.5 Arterial oxygen pressure (PaO2) is <8 kPa (60 mm Hg) with normal or low arterial carbon dioxide pressure (PaCO2).6,7
  • Type 2 Respiratory Failure (hypercapnic): occurs when alveolar ventilation is insufficient to excrete the carbon dioxide being produced. Inadequate ventilation is due to reduced ventilatory effort or inability to overcome increased resistance to ventilation. It affects the lung as a whole, and therefore carbon dioxide accumulates, presenting with PaO2 of <8 kPa (60 mm Hg) or normal, with hypercapnia PaCO2 >6.0kPa (> 50 mm Hg).5,7

Preventing Type 1 and Type 2 Respiratory Failure

Preventing respiratory failure starts with being aware of possible risk factors and causes

Causes of type 1 respiratory failure include: pulmonary oedema, pneumonia, COPD, asthma, acute respiratory distress syndrome, chronic pulmonary fibrosis, pneumothorax, pulmonary embolism, pulmonary hypertension.5,7

Type 2 respiratory failure is commonly caused by COPD but may also be caused by chest-wall deformities, respiratory muscle weakness and Central nervous system depression (CNS depression.)5 CNS depression is associated with reduced respiratory drive and is often a side effect of sedatives and strong opioids. It may also be caused by severe asthma, myasthenia gravis, muscle disorders, obesity , hypothyroidism and adult respiratory syndrome.7

Once aware of individual risk factors, healthcare professionals are able to plan interventions that minimize risk and reduce the likelihood of increased morbidity and mortality.

Detecting Type 1 and Type 2 Respiratory Failure

  • Blood gas analysis: helps professionals identify the type of respiratory failure, which is crucial to indicate what respiratory support may be needed.8 Type 1 respiratory failure may require only supplementary oxygen, but type 2 failure may require additional support such as continuous positive airway pressure (CPAP) or biphasic positive airway pressure (BiPAP) to increase exchange of both gases and, where possible, reverse any causes for low tidal volumes or low respiratory rates.8 Blood gas analysis will also be useful in monitoring the clinical condition throughout treatment and recovery.
  • Capnography: provides a continuous reading of respiratory function and end tidal CO2.
  • Pulse oximetry: gives a continuous measure of blood oxygen saturation.7 
  • ECG: to monitor cardiac function as tachycardia and cardiac arrhythmias may result from hypoxaemia and acidosis.7
Patients may also present other signs and symptoms of respiratory failure:6
Symptoms and signs of hypoxemia Symptoms and signs of hypercapnia
Dyspnoea, irritability Headache
Confusion, somnolence, fits Change of behaviour
Tachycardia, arrhythmia Coma
Tachypnoea Papilledema
Cyanosis Warm extremities

Interventions for Type 1 and Type 2 Respiratory Failure

Intervening in cases of respiratory failure includes not only supportive measures as well as treatment of the underlying cause.Depending on presentation, interventions aim to correct hypoxemia or hypercapnia and respiratory acidosis.

  • Correction of hypoxemia: aim to maintain adequate oxygenation, achieved with an arterial oxygen pressure (PaO2) of 60 mm Hg. The inspired oxygen concentration should be adjusted at the lowest level which is sufficient for tissue oxygenation.6 Oxygen can be delivered via nasal canula, simple face mask, nonrebreathing mask or high flow nasal canula. In severe cases, patient may require invasive ventilatory support.
  • Correction of hypercapnia and respiratory acidosis: this is achieved by treating the underlying cause or providing ventilatory support.6

Type 1 and type 2 respiratory failure is a serious medical condition. Mortality associated with respiratory failure depends on the underlying cause as well as the speed of diagnosis and efficacy of management.7 Being able to prevent, detect and intervene adequately is crucial for improved patient outcomes.

About the author

My name is Andreia Trigo RN BSc MSc, I am a nurse consultant with over a decade of experience in anaesthesia, sedation and pain management.

This involves patient care, as well as lecturing at post grad level on these topics, presenting at conferences and co-developing a very successful sedation course at SedateUK. My passion for creating safer environments for patients and professionals led me to collaborate with Medtronic and share my knowledge and expertise with our professional community.


The content of this article is written by a blogger with whom Medtronic has a relationship. However, the contents represent the personal objective views, comments and techniques of the blogger and are not statements from Medtronic. To the extent this material might contain images of patients or any material where a copyright is held by a third party, all necessary written permissions from the patient or copyright holder, as applicable, with respect to use, distribution or copying of such images or copyrighted materials has been obtained by the blogger.

  • 1. Post-operative patients with Respiratory Compromise have a mortality rate of 10.4% compared to 0.4% of those who do not develop Respiratory Compromise - Development and validation of a score to predict postoperative respiratory failure in a multicentre European cohort: A prospective, observational study. Canet et al EJA 32(7):458–470, JUL 2015

  • 2. Canet et al. Development and validation of a score to predict postoperative respiratory failure in a multicentre European cohort: A prospective, observational study. EJA 32(7):458–470, JUL 2015

  • 3. Medtronic data analysis

  • 4. Puneet Katyal. Pathophysiology of  Respiratory Failure and Use of Mechanical Ventilation. American Thoracic Society Available at

  • 5. Health Engine (2003) Respiratory failure (types I and II) Available at

  • 6. Eman Shebl; Bracken Burns (2019) Respiratory Failure. NCBI Available at

  • 7. Colin Tidy (2015) Respiratory failure. Patient Available at

  • 8. Philip Woodrow (2002) The symptoms and management of respiratory failure. Nursing Times Available at