Respiratory compromise in children presenting to an urban emergency department of a tertiary hospital in Tanzania: a descriptive cohort study

Respiratory compromise is the leading cause of death worldwide, especially in children below the age of 5 years [1, 2]. Most of these deaths occur in low-income countries (LICs). Respiratory compromise is more common in children than in adults because of anatomical and physiological differences like small airway, immature immune system and under developed compensatory mechanisms.

Respiratory compromise is a continuum of respiratory distress, respiratory failure and respiratory arrest. Respiratory failure refers to failure of oxygenation or ventilation or both and respiratory distress refers to increased work of breathing [3]. Early identification, early intervention and close monitoring can mitigate against poor outcomes [4‐6]. Such interventions are best provided in an emergency department where practitioners are trained in the management of such patients [7].

Tanzania health system consists of dispensaries at village level, health centres at ward level, district hospital, regional hospital, zonal hospital and national hospital. Patients including children are referred from low-level facility to higher-level facility. In Tanzania there is no children hospital, so Muhimbili National Hospital receives both adult and children from all regional hospitals and some directly from home and from private hospitals [8].

Tanzania opened its first full capacity emergency department in 2010 and began a residency-training program at that time. Current emergency medicine practice in LICs is based on research primarily conducted in high-income countries, where the aetiology, severity and resources available to treat patients with respiratory compromise are very different from LICs. Despite the ongoing advancement in the development of the emergency care infrastructure in Tanzania [9], there is insufficient data to guide development of specific clinical guidelines for training, management and resources required to treat paediatric patients with respiratory compromise in acute care settings in limited income settings [10].

To address the paucity of data, we aimed to describe the clinical epidemiology, management and outcomes of paediatric patients with respiratory compromise presenting to the first full capacity emergency medicine department in Tanzania.

During the enrolment times, 165 children with respiratory compromise attended the EMD and all consented to be in the study. Among them 92 (55.8%) presented in respiratory failure, 73 (44.2%) in respiratory distress and no children had respiratory arrest during enrolment (Fig. 1).

Globally, respiratory compromise in the paediatric population is the leading cause of emergency visits, cardiac arrest, ICU admission and prolonged hospital stay [5, 10, 12]. In Tanzania the burden, clinical epidemiology, management and outcomes of acute respiratory compromise among paediatric population attending acute care settings has not been previously documented.

In our study, the majority of children with respiratory compromise were below age 5 years, more than half had respiratory failure on arrival and one third died before hospital discharge. The median age of children who died was 8 months, suggesting that those under one year are a particularly vulnerable group. Nearly half of the children enrolled had comorbidities, the most common being congenital heart disease. Pneumonia was the most frequent diagnosis. Notably, the majority of children presented in respiratory failure, and only 12% received ICU care. Risk of death was higher among children who presented in emergency department with hypoxia, decreased level of consciousness, bradypnoea and those who received cardiopulmonary resuscitation, intubation, and airway adjunct insertion in EMD. The risk of death among intubated children was high, because most children were intubated after developing cardiac arrest, and thus there was a delay in EMD in initiating assisted ventilation.

Similar findings regarding the young age of paediatric patients presenting with respiratory compromise have been reported in India, China, Zambia, and Nigeria [5, 13‐15]. Children under five years are more likely to develop respiratory compromise than other age groups because of their small airway, underdeveloped central nervous system, less energy store and other anatomical differences compared with older children [16]. They also have higher risk of Respiratory Syncytial Virus infection and this is particularly true of those below one year of age [17].

In our study, the proportion of children arriving with respiratory failure was higher than reported in studies in India and Canada [14, 18]. This finding is likely a result of delayed presentation or delayed transfer to our hospital, which has been documented for other illnesses in LICs.

The leading cause of respiratory compromise was pneumonia, then congenital heart disease and sepsis but the leading causes of death were pneumonia followed by sepsis and congenital heart disease. This is consistent with previous studies in LICs; in Nigeria, Zambia and Malawi, pneumonia was the leading cause of death [6, 14, 19]. A study from India also reported pneumonia as the leading cause of death [14].

In this study, we found that the use of investigations varied. For example, while almost all children had random blood glucose and malaria testing, blood gas analysis was performed in only about half of paediatric patients with respiratory compromise. In a study conducted in India among children with acute respiratory failure, blood gas analysis was performed in all paediatric patients [14]. Blood gases were not performed in our department either due to the cost to the patient or intermittent availability of reagent; a previous study in Ghana described similar barriers to testing [6]. Sawe et al. in 2011 reported unavailability of blood gas analyzer machines in all main referral hospital ICUs in Tanzania [20]. The lower frequency of blood gas analysis seen in this study demonstrates that relying on such investigations is not always practical in low income countries and thus emergency care providers must depend on clinical features to diagnose respiratory failure.

Perhaps surprisingly, chest radiography was performed in only one third of the children. Clinicians in our department may not order chest radiography probably because of the poor quality of portable chest radiography in our hospital, and children were too sick (87% were on oxygen therapy) to go to the radiology department for imaging. There is also an increasing use of point of care lung ultrasound in our department.

Most children received oxygen therapy; however, only 11% received mechanical ventilation. In a study in India with a comparable group of patients, mechanical ventilation was required in 33.9% of children with respiratory failure in the emergency department [14]. This suggests that there are insufficient resources in our setting. At the time of this study, MNH had no paediatric ICU, children who require intensive care are admitted to the adult medical ICU which had only 13 bed capacity and no ventilators which can support children of young ages [18]. In Canada and India all paediatric patients with respiratory failure were admitted to ICU from emergency department [14, 18]. Notably, the overall mortality was two times higher in this study than in the study in India.

The high mortality rate of our population can be attributed to several potential reasons. The majority of children arrived in EMD after developing respiratory failure and thus had less reserve despite attempts at lifesaving intervention. The risk factors for mortality reflect this end-stage disease; decreased consciousness, hypoxia and bradypnoea, cardiac arrest, and the need for ventilation. A second reason may be failure of EMD physicians to initiate invasive measures sooner; the median length of stay for children who developed cardiac arrest in our department was 6 h, suggesting that there may have been opportunity to intervene sooner if respiratory failure had been recognised. However, another reason for delayed intervention may be the lack of ventilators in the EMD and in hospital main ICU. Finally, the high mortality is likely attributable to the low ICU admission rate resulting from a lack of a paediatric ICU and less ICU bed capacity in the adult ICU [18, 20]. Another possibility could be poor adherence to respiratory management guidelines or poor quality of interventions.

Paediatric patients presenting to our EMD with respiratory compromise had a high mortality rate. This is likely due to a combination of late presentation, in which the majority was in respiratory failure, underlying comorbidities, and limitations on resources. This information suggests that efforts should be placed on early recognition and referral, developing standard investigation and resuscitation algorithms for the EMD, and allocating additional resources for critical care.