Abstract
Introduction
In 2015, the Lancet Commission on Global Surgery highlighted the disparities that exist around the world in terms of health care and access to care. About two-thirds of the world's population does not have guaranteed access to adequate surgical care. 1
Dewan and colleagues 2 have suggested that, according to the World Bank Classification, 80% of people with a need for neurosurgical treatment reside in low-income countries (LICs) and lower middle-income countries (LMICs) 3 (Fig. 1). An estimated 5 million people with neurosurgical conditions will not undergo a surgical procedure in Sub-Saharan Africa and Southeast Asia, where there are significantly fewer neurosurgeons available than the number of procedures needed.
Countries' economical rankings according to the World Bank Classification.
Traumatic brain injuries (TBIs) are one of the leading causes of death and disability worldwide in the younger population. 4 About 69 million new TBI cases are estimated to occur each year worldwide. 5
Moreover, according to a recent article, 2 surgery for the treatment of a TBI is the most common neurosurgical procedure all over the world, and in LMICs, it is even more important compared with other neurosurgical procedures. 6
The ability to define the appropriate care management and apply the correct prevention strategies requires a global analysis of data on the incidence and management of head injuries.
Epidemiology and Causes of Trauma
In high-income countries (HICs), there has been a significant increase over time in the mean age of patients included in clinical studies of TBI. In the Traumatic Coma Data Bank data in the 1980s, the mean age was 25 years, 7 the European Brain Injury Consortium studies in the 1990s showed a mean age of 38 years, 8 and a recent study by the CENTER-TBI group showed a mean age over 50 years. 9 With the increase in life expectancy, patients with head trauma reflect a new trend in this pathology in HICs. Elderly patients with multiple comorbidities and on anticoagulants undergoing neurosurgical treatment will have a worse clinical neurological outcome. 10
As a consequence of the increased age of patients, the prevailing mechanism of trauma has changed in HICs, with incidental falls predominating over road traffic accidents (RTAs). 9
Head injuries following RTAs and assault are more common in LMICs, where we observe the highest overall burden related to head injuries. 11 Limited access to neurosurgical treatment can impact clinical and neurological results, expand disability, and increase the mortality rate. In LMICs, the number of head injuries from road accidents is also likely to increase with the continuous expansion of motorization without prevention measures such as the use of crash helmets (Fig. 2). A review of recent articles showed that because of the prevailing mechanism of trauma, the mean age of patients with TBI admitted to the hospital in these countries was found to be approximately 30 years. 12
Absence of helmet protection with six people on a single motorbike.
Clinical and Surgical Differences
The main traumatic mechanisms listed above and the difference in the ages of the HIC and LIC-LMIC populations explain the different incidences of the procedures performed. In HICs, the evacuation of acute and chronic subdural hematomas represents the main neurosurgical procedure for trauma performed, whereas in LICs-LMICs, the main procedures performed for head trauma are the evacuation of extradural hematoma and the elevation of depressed skull fractures. 13 In fact, extradural hematomas and depressed fractures are the most common contact injuries and are prevented by using crash helmets. 14
Also, the indication for cranial decompression (the most common surgical procedure for trauma) differs substantially. In the Western world, there are the “classic” two types of decompression: the primary decompression with or without hematoma evacuation (see the Randomized Evaluation of Surgery with Craniotomy for patients Undergoing Evaluation of Acute SubDural Hematoma [RESCUE-ASDH] 15 and the secondary decompression driven by intracranial (ICP) monitoring for early 16 or late 17 ICP control. In countries with limited facilities, there is a sort of “preventive” decompression: whenever an admission computed tomography (CT) scan shows multiple lesions with possible future evolution, cranial decompression is an early form of treatment to avoid the necessity of follow-up CT scans and of long intensive care unit (ICU) monitoring (which is seldom available). This is why, in some countries, cranial decompression is performed primarily on patients with moderate or mild injuries, 18 whereas in HICs, almost all the patients undergoing cranial decompression are severely injured.
Further, cranial reconstruction is a problem in low-resource settings. The patient is often lost to follow-up or does not want to come back for a second surgery. As a result, two different surgical techniques have been suggested to control refractory ICP without cranial decompression. Hinge or floating craniotomy is a technique of enlargement of cranial content without bone flap removal where there is no evidence of worse outcomes as compared with cranial decompression. 19 The use of cysternotomy (opening of basal cysterns with or without associated decompression) to control ICP has been investigated recently in small randomized clinical studies with controversial results. 20,21 For both techniques multi-center randomized studies are needed to confirm their standard use to decrease refractory ICP. 22
Publications in Neurotrauma and Consequences for Guidelines Production
There are 3 billion people in LICs-LMICs, with approximately 15,000 neurosurgeons out of a total of 50,000 worldwide. According to a recent article, only 4.5% of articles published in the neurosurgical literature came from these countries between 2015 and 2017. 23 From 2017 until now, there has been increasing interest in the concept of global neurosurgery. 24 A new study was conducted from 2018 to 2020 with the same methodology. Unfortunately, no significant difference was shown in the publication capacity of countries with limited resources. In terms of publication capacity, India, which was already by far the most contributing country, now represents over 72% of the total publication capacity of these countries. 25 If we look at the most cited articles on TBI both in children 26 and in adults 27 in the field of neurotrauma, the contribution of LICs-LMICs is very limited.
We can also add the consideration that only about 8% of class 1 randomized clinical studies are performed in these countries. 28 As a result, it is clear that only HICs produce evidence-based guidelines. 29 As an example, the RESCUE ICP study showed a significant clinical improvement in the patients located in the surgical arm at 12 months and 24 months after injury. 30 How many countries worldwide can provide intensive rehabilitation, cranial reconstruction, and management of post-traumatic hydrocephalus for such a long time after trauma? When we compare the capacity for publication and the production of guidelines with the epidemiological incidence of TBI, we see a huge disparity: where trauma is an endemic disease, there are few publications, whereas most publications come from areas with a lower incidence. 31 There is a need for the creation of guidelines and protocols for head injury management that can be used in LICs-LMICs. 32
What Are Our Duties to Improve This Situation?
In Table 1, we have summarized the different features of TBI in LICs-LMICs and in HICs.
Epidemiological, Clinical, and Surgical Features of Patients Treated for TBI in Low-Income Countries/Lower Middle-Income Countries as Compared with High Income Countries
Data are from recent studies; see text.
HIC, high-income country; ICP, intracranial pressure; LIC, low-income country; LMIC, low middle-income country; TBI, traumatic brain injury.
In recent years, there has been an increase in awareness about the concept of global neurosurgery, but unfortunately, until now, it has not generated increased scientific output in countries with limited facilities. 25 It is time now, in our opinion, to discuss how mortality and morbidity for a worldwide “disease” such as TBI can be improved on a worldwide basis.
Epidemiological and clinical studies should include LICs-LMICs, as has been done partially in the CENTER-TBI study. 9 Even if the price to pay is less accuracy in the follow-up, we have to consider that in most countries, a 14-day mortality rate and/or a discharge Glasgow Outcome Scale (GOS) is an acceptable outcome measure 13 and probably the only feasible one worldwide. As has been demonstrated in India, in the absence of proper intensive rehabilitation, the difference between discharge and 6 months of follow-up GOS is negligible. 33 We all know that in Western HICs the Glasgow Outcome Scale Extended (GOSE) will vary considerably between discharge and long-term assessments, especially for surgically treated patients, 30 but we have to find a way to conduct parallel studies in order to be as inclusive as possible.
It is possible to include LICs-LMICs in class 1 randomized clinical trials of TBI, and it has already been done in the RESCUE-ASDH study, 15 with the largest recruiting center in Bangalore, India. This will eventually allow us to include these countries in the process of developing evidence-based guidelines. Meanwhile, the use of consensus conferences with the inclusion of experts from all areas of the world will produce management suggestions that can probably be used worldwide. 34,35
Collaboration in international studies, as well as “twin university systems” such as the one between Cornell University and a neurosurgical institute in Tanzania, 36 must be made available to a growing number of countries. The possibility to exchange trainees and to contribute to data collection and publication will transform the previous concept of a “charity” work into an educational process that can influence over time the worldwide care of patients with TBI. We are aware of the obstacles induced by the lack of neurosurgeons and dedicated resources, but the above-mentioned steps are also important.
Conclusions
We (the neurotrauma community, the Brain Trauma Foundation, the American Association of Neurological Surgeons, the Joint Section on Neurotrauma and Critical Care, and the European Brain Injury Consortium) were the first to publish a set of guidelines in neurosurgery. 37 Because TBI is an endemic disease in most of the world and surgery for TBI is the first surgical intervention in many countries, we need to be among the first neurosurgeons to open a new era of collaboration.
As it is in the motto of the European Brain Injury Consortium, nemo solo satis sapit (none knows enough alone), we need to transform disparities and inequities into an enrichment of our scientific production.