Every year, over 5.9 million children die, mostly from preventable or easily treatable diseases, and more than 95% of those deaths occur in developing countries. Pneumonia is the leading cause of death in children under 5 years of age, being responsible for at least 18% of all deaths in this age category.
In 2010, there were an estimated 120 million episodes of pneumonia in children under 5 years, of which 14 million progressed to severe disease and 1.3 million led to death. Hypoxaemia (insufficient oxygen in the blood) is the major fatal complication of pneumonia, increasing the risk for death many times. It is estimated that at least 13.3% of children with pneumonia have hypoxaemia, corresponding to 1.86 million cases of hypoxaemic pneumonia each year.
A further 23% of the 5.9 million annual child deaths result from neonatal conditions such as birth asphyxia, sepsis and low birth weight, all of which can lead to hypoxaemia. These add to the substantial burden of hypoxaemia, especially in developing countries.
Despite its importance in virtually all types of acute severe illness, hypoxaemia is often not well recognized or managed in settings where resources are limited. Oxygen treatment remains an inaccessible luxury for a large proportion of severely ill children admitted to hospitals in developing countries. This is particularly true for patients in small district hospitals, where, even if some facility for delivering oxygen is available, supplies are often unreliable and the benefits of treatment may be diminished by poorly maintained, inappropriate equipment, poorly trained staff or inadequate guidelines.
Increasing awareness of these problems is likely to have considerable benefits for clinical and public health. Health workers should know the clinical signs that suggest the presence of hypoxaemia. More reliable detection of hypoxaemia could be achieved through more widespread use of pulse oximetry, which is a non-invasive measure of arterial oxygen saturation. Oxygen therapy must be more widely available; in many remote settings, this can be achieved by use of oxygen concentrators, which can run on regular or alternative sources of power.
Several conditions must be met for hypoxaemic children to receive appropriate, uninterrupted oxygen therapy for as long as is necessary to save their lives. First, a child must be recognized as hypoxaemic, either by a trained health care provider on the basis of clinical signs or with a pulse oximeter. Then, the child recognized as hypoxaemic must receive adequate, uninterrupted oxygen therapy for an adequate duration.
Many developing countries have growing experience in the clinical, organizational, biomedical technology and training aspects of setting up and sustaining effective oxygen delivery systems in hospitals and small health facilities. There is strong evidence that use of pulse oximetry and the availability of reliable oxygen sources in district and provincial hospitals can reduce death rates from pneumonia by about one third.
This manual focuses on the clinical aspects of oxygen therapy in children in health facilities. We hope that it will stimulate efforts to improve oxygen systems worldwide by describing practical aspects for health staff, biomedical engineers, administrators and health officers.