A reply

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 correctly utilised pulse oximetry 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 oximetry during all anaesthesia and if resources were constrained, oximetry should take precedence over other monitoring. 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 that preserve oxygenation’. Our experience is that the preservation of their patients’ oxygenation is the primary motivation of all anaesthetists and the evidence is overwhelming for the value of oximetry in detecting hypoxaemia [1]. He suggests that there has been insufficient consultation with providers from low-income countries. However, consultation has been wide, including providers from low-income countries, and 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 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; 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 involving 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. No external funding and no competing interests declared.Previously posted at the Anaesthesia Correspondence website: http://www.anaesthesiacorrespondence.com