I read with interest the recent editorial by Merry et al. However, I feel that the rationale of the Global Oximetry Project discussed is questionable [1]. It is dependent on the belief that the decline in anaesthetic mortality in developed countries is primarily due to pulse oximetry and that this can automatically be extrapolated globally if oximetry use is expanded worldwide. There is virtually no evidence to support this or the feasibility of implementing the project.

If the significance of pulse oximetry in changing outcome is debatable in developed countries, then there is every reason to question its benefit in developing countries [2]. Indeed, less sophisticated surgery, anaesthetic techniques which preserve oxygenation, infrequent use of opioids and a different patient population should tend to reduce the incidence of perioperative hypoxaemia. Apart from the difficulties in procuring, maintaining and repairing pulse oximeters in the developing world, there is the crucial issue of the appropriate use of pulse oximetry by anaesthesia providers, whose motives and circumstances differ vastly from their western counterparts.

I believe that the pilot project, described in the same Anaesthesia issue, has limited value since the countries chosen fall into the Medium Human Development group (according to 2009 rankings) and are not undisputedly poor [3, 4]. If anything, the pilot indicates that a larger educational package is required, that oximeters should not be provided in middle income countries, and raises doubts about the robustness of the pulse oximeters chosen, and their overall costs, which are all at odds with the notion of global provision of oximeters.

Details of the Global Oximetry project may be found online [5]. The strategy of the World Health Organisation (WHO) seems strange. The main problems in the poorest countries are the quantity and quality of surgery; instead the WHO have focused on perioperative mortality (which will not become a significant problem until surgery numbers increase), The WHO have not sufficiently analysed the problems or evaluated the potential solutions, of which pulse oximetry is only one.

At the inaugural meeting of the project, local participants were grossly under-represented, with not one anaesthesia provider coming from a developing country. The majority of participants were anaesthetists and WHO clinical advisers, but one might have expected experts from other fields such as anthropology and human development to contribute in this kind of undertaking. The significant representation of the medical technology industry suggests commercial gains are at stake and this does little to support local ownership or even the image of the WHO. Finally, there is no account of how the WHO will manage in countries where they have no access.

The Global Oximetry project is a vertical programme which, like all such programmes that target specific health issues, may have unintended detrimental effects on local economies and other aspects of health, often by diversionor depletion of resources. These issues have not been mentioned by the WHO. I believe this project is potentially cost-inefficient and western donors, the main WHO contributors, should expect to see their money spent wisely, backed by robust evidence.

CJ King

Consultant

Department of Anaesthesia

National University Hospital

Singapore

E-mail:krisk@northrock.bm

No external funding and no competing interests declared

References

1     Merry AF, Eichorn JH, Wilson IH.Extending the WHO ‘Safe Surgery Saves Lives’ project through Global Oximetry.Editorial. Anaesthesia 2009; 64: 1045-1048.

2     Pedersen T, Dyrlund Pedersen B, MøllerAM. Pulse oximetry for perioperative monitoring. Cochrane Database ofSystematic Reviews 2003; 3: CD002103.

3     Walker IA, Merry AF, Wilson IH et alon behalf of the GO Project teams. Global oximetry: an internationalanaesthesia quality improvement project. Anaesthesia 2009; 64: 1051-1060.

4     UNDP. Human Development Report 2009. http://hdr.undp.org/en/reports/global/hdr2009/(accessed 7^th May 2010).

5     WHO. Global Pulse Oximetry Project. http:// who.int/patientsafety/safesurgery/pulse_oximetry/en/index.html (accessed 7^thMay 2010)

Thank you for the opportunity to respond to Dr King’s letter. In our editorial, we discussed the evidence for the value of pulse oximetry but reached a different conclusion [1].

We did not assert that the decline in anaesthetic mortality in high-income countries is attributable primarily to the advent of pulse oximetry. Improved safety in anaesthesia is attributable to better training, drugs, equipment, and monitoring. We did state that there is substantial evidence that pulse oximetry, when correctly used, is very important for safety in anaesthesia. Clinical equipoise does not exist, so the very large randomised controlled trial required to demonstrate improved mortality would not be  ethically justified.

We wonder if Dr King would be happy to remove pulse oximetry at his own institution, and put the money saved towards more evidence-based initiatives to promote patient safety?  If not, the implication is that he advocates one safety standard for wealthy healthcare systems and a lower one for the less wealthy. We advocate pulse oximetry during all anaesthesia, and furthermore, if resources were constrained, pulse oximetry should take precedence over other monitoring. Pulse oximetry is the one electronic technology included in the 19-point World Health Organization (WHO) Surgical Safety Checklist for exactly this reason. The cost of pulse oximetry is no longer high, and the aim is to provide it even more inexpensively.

Dr King refers to the ‘crucial issue of the appropriate use of pulse oximetry by anaesthesia providers whose motives and circumstances differ vastly from their western counterparts’ and advocates ‘anaesthetic techniques which preserve oxygenation’. Our experience is that the preservation of patients’ oxygenation is the primary motivation of all anaesthetists, and the evidence is overwhelming for the value of pulse oximetry in detecting hypoxaemia [1].

Dr King also suggests that there has been insufficient consultation with providers from low-income countries. However, consultation has been wide, including providers from low-income countries. His description of the composition of the inaugural meeting of the project is incorrect. The General Assembly of the World Federation of Societies of Anaesthesiologists (WFSA) in Cape Town (2008) considered and endorsed revised Standards for a Safe Practice of Anaesthesia, which included mandatory monitoring with pulse oximetry. Representatives from many low-income countries were present. A recent survey of WFSA member societies (including low income countries) will shortly be published [2]. No national society of anaesthetists that responded has minimal standards for safe anaesthesia that do not include the mandatory use of pulse oximetry. We have received feedback that greater emphasis on pulse oximetry by the WHO and WFSA is appreciated by and will assist providers in low-income areas to obtain necessary funding. Furthermore, it is not (as Dr King alleges) a vertical programme; the reliable detection of hypoxemia is important not only during anaesthesia, but also in recovery, trauma care, resuscitation (notably of newborn infants), critical care, and respiratory disease. The Global Oximetry project is focussed on the operating room, but its potential gains are far-reaching.

We agree with Dr King that simply providing oximeters would be unlikely to improve patient care. That is why this initiative includes the WHO Surgical Safety Checklist [3], provision for education, and appropriate warranties and provision for maintenance as well as cost-effective and appropriately specified pulse oximeters. Safety in anaesthesia depends on many other things, and this is the message underpinning the WHO initiative [4]. We hope that one change will lead to others, to achieve positive, sustainable improvements in practice in at least some parts of the world. We are well aware of the risk of unintended consequences; the WHO is conducting further pilot studies assessing the impact of the Surgical Safety Checklist and pulse oximetry intervention.

We are unclear how Dr King comes to the conclusion that pulse oximeters should not be provided to middle-income countries: the distribution of health expenditure in many countries is uneven, and there are regions within such countries that will benefit from this initiative. We acknowledge that it may not be possible to extend the project to every region of the world, but this is surely no reason not to proceed in those areas where the project may be worthwhile?

Regarding commercial interests, we advise Dr King that a rigorous process is ongoing which involves independent adjudication of submitted proposals, following a public and open invitation to all manufacturers to participate.

Perhaps Dr King’s most interesting proposition is the need for more surgery, rather than for safer surgery. Certainly more surgery is needed in many parts of the world [5]. However, rates of anaesthesia mortality in some areas are so high that the risk of elective surgery is unacceptable [6-8]. A substantial proportion of the burden of disease is amenable to surgical intervention, and the global oximetry initiative is only one part of a wider strategy to improve the lot of all patients undergoing surgery and anaesthesia.

Perhaps Dr King’s most interesting proposition is the need for more surgery, rather than for safer surgery. Certainly more surgery is needed in many parts of the world [5]. However, rates of anaesthesia mortality in some areas are so high that the risk of elective surgery is unacceptable [6-8]. A substantial proportion of the burden of disease is amenable to surgical intervention, and the global oximetry initiative is only one part of a wider strategy to improve the lot of all patients undergoing surgery and anaesthesia.

A. F. Merry

University of Auckland and Auckland City Hospital, Auckland, NZ

J. H. Eichhorn

Department of Anesthesiology, Univ. of Kentucky College of Medicine, Lexington, KY, USA

I. H. Wilson

Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, UK

RReferences

1.        Merry AF, Eichhorn JH, Wilson IH. Extending the WHO 'Safe Surgery Saves Lives' project through Global Oximetry. Anaesthesia 2009; 64: 1045-8.

2.        Funk L, Weiser T, Berry W, Lipsitz S, Merry A, Enright A, et al. Global operating room distribution and pulse oximetry supply: an estimation of essential infrastructural components for surgical care. Lancet 2010; In press.

3.        Haynes AB, Weiser TG, Berry WR, Lipsitz SR, Breizat AH, Dellinger EP, et al. A surgical safety checklist to reduce morbidity and mortality in a global population. New England Journal of Medicine 2009; 360 :491-9.

4.        Walker IA, Wilson IH. Anaesthesia in developing countries - a risk for patients. Lancet 2008; 371: 968-9.

5.        Weiser TG, Regenbogen SE, Thompson KD, Haynes AB, Lipsitz SR, Berry WR, et al. An estimation of the global volume of surgery: a modelling strategy based on available data. Lancet 2008; 372: 139-44.

6.        Ouro-Bang'na Maman AF, Tomta K, Ahouangbevi S, Chobli M. Deaths associated with anaesthesia in Togo, West Africa. Tropical Doctor 2005; 35: 220-2.

7 .       Heywood AJ, Wilson IH, Sinclair JR. Perioperative mortality in Zambia. Annals of the Royal College of Surgeons of England 1989; 71: 354-8.

8  .      Fenton PM, Whitty CJ, Reynolds F. Caesarean section in Malawi: prospective study of early maternal and perinatal mortality. British Medical Journal 2003; 327: 587.