To the Editor!
We have read the original contribution by Sutcu Cicek et al. [1] with high interest regarding the effect of nail polish and henna on pulse oximetry readings. In their study, these authors report on the influence of both factors in 33 normoxic healthy females. Although the study is interesting, it has significant limitations, which must be addressed.
To our surprise, the authors state, it is not proven that nail polish effects the accuracy of pulse oximeters [1]. However, several randomized, controlled trials with both healthy persons and critically ill patients report on the effect of nail polish on oxygen saturation measured by pulse oximetry [2, 3, 4]. Interestingly, some of these studies have been cited by the authors themselves.
Sample size calculation prior to beginning of a trial is obligate to determine the significance of results. Unfortunately, in this trial an adequate mathematical sample size calculation was obviously waived. Therefore, results of the present study cannot be interpreted regarding both the statistical significance and the clinical relevance.
To determine pulse oximetry accuracy, intermittent arterial blood gas analyses (ABGA) are essential [3]. However, accuracy in the present study was only determined by consecutive pulse oximeter measurements over a specific duration, which may alter pulse oximetry readings. A major limitation of the present study is that accuracy is not analyzed in the present study al...
To the Editor!
We have read the original contribution by Sutcu Cicek et al. [1] with high interest regarding the effect of nail polish and henna on pulse oximetry readings. In their study, these authors report on the influence of both factors in 33 normoxic healthy females. Although the study is interesting, it has significant limitations, which must be addressed.
To our surprise, the authors state, it is not proven that nail polish effects the accuracy of pulse oximeters [1]. However, several randomized, controlled trials with both healthy persons and critically ill patients report on the effect of nail polish on oxygen saturation measured by pulse oximetry [2, 3, 4]. Interestingly, some of these studies have been cited by the authors themselves.
Sample size calculation prior to beginning of a trial is obligate to determine the significance of results. Unfortunately, in this trial an adequate mathematical sample size calculation was obviously waived. Therefore, results of the present study cannot be interpreted regarding both the statistical significance and the clinical relevance.
To determine pulse oximetry accuracy, intermittent arterial blood gas analyses (ABGA) are essential [3]. However, accuracy in the present study was only determined by consecutive pulse oximeter measurements over a specific duration, which may alter pulse oximetry readings. A major limitation of the present study is that accuracy is not analyzed in the present study although it is most important in patients who have nail polish applied, e.g. to identify hypoxia. The authors only report on mean values (given in percent) but omit to verify their measurements, e.g. with ABGA.
Additionally, the presented results also lack standard deviation (SD). Independently, one may assume that the presented differences (max. 1,25%) are not clinically relevant, which is in congruency to other publications [2, 3, 4]. In the present trial one may therefore speculate the differences identified might be due to slightly alternating oxygen saturation values in spontaneously breathing persons.
In conclusion, the present study does not add significant new data for nail polish to the present knowledge.
References:
[1] Sutcu Cicek H, Gumus S, Deniz O, Yildiz S, Acikel CH, Cakir E, Tozkoparan E, Ucar E, Bilgic H. Effect of nail polish and henna on oxygen saturation determined by pulse oximetry in healthy young adult females. Emerg Med J. 2010 Oct 5. [Epub ahead of print]
[2] Cote CJ, Goldstein EA, Fuchsman WH, et al. The effect of nail polish on pulse oximetry. Anesth Analg 1988;67:683
[3] Hinkelbein J, Genzwuerker HV, Sogl R, Fiedler F. Effect of nail polish on oxygen saturation determined by pulse oximetry in critically ill patients. Resuscitation. 2007 Jan;72(1):82-91
[4] Rodden AM, Spicer L, Diaz VA, Steyer TE. Does fingernail polish affect pulse oximeter readings? Intensive Crit Care Nurs. 2007 Feb;23(1):51-5.
The articles on the problems of Emergency Department (ED)
overcrowding make interesting reading, as the problems outlined are
familiar to us in the UK, and I am sure that we would all identify similar
causes and both short and long term solutions.[1]
The list of stopgap measures, in the article by Fatovich and Hirsch [1]
is also familiar to us all. Ambulance diversion is difficult outside
larg...
The articles on the problems of Emergency Department (ED)
overcrowding make interesting reading, as the problems outlined are
familiar to us in the UK, and I am sure that we would all identify similar
causes and both short and long term solutions.[1]
The list of stopgap measures, in the article by Fatovich and Hirsch [1]
is also familiar to us all. Ambulance diversion is difficult outside
large cities with multiple EDs. Chief Executives are under pressure to
avoid it. Similar problems arise with regard to postponing elective
surgery. Reopening inpatient beds will take time, and the same applies to
increasing the size and staffing of our EDs.
Much work nationally has been put into improving discharge processes,
with notable successes. However bed management itself remains a big issue
that is not really discussed by Fatovich and Hirsch. In my experience
the number of times that there are genuinely no empty beds are rare, the
beds are usually "the wrong type of bed". It cannot be denied that
placing patients on outlying wards belonging to other specialties, even
in their recovery phase, carries some clinical risk, and adds to the time
need to complete ward work; this has led to resistance amongst our
colleagues. Overcrowding of EDs, however must be a greater clinical
risk.
This is an area that has not been discussed publicly. I would
suggest the time has now come that we should stimulate this as a national
issue. Resolution of ED overcrowding, in both the short and long term is
a Trust-wide, and NHS-wide problem. Most of the solutions are beyond our
individual control, and can only be achieved by working with our
colleagues for the corporate good of our patients. By working together to
utilise scarce beds even more efficiently I believe we can reduce the
overflow problem, without impacting on elective activity.
This is yet another stopgap, but one that has not been openly
discussed. Is it time we started this debate?
Reference
(1) Fatovich DM, Hirsch RL. Entry overload, emergency department overcrowding, and ambulance bypass. Emerg Med J 2003;20:406-409.
The best evidence topic report (BET) by Hogg and Mahu [1] raises a
number of concerns, both with the article itself and the BETs process as a
whole. The relative efficacy of adrenaline and vasopressin in the
management of cardiac arrest is an important subject of relevance to all
who work in Emergency Medicine. For this BET to only include those papers
directly comparing vasopressin and adrenaline is to...
The best evidence topic report (BET) by Hogg and Mahu [1] raises a
number of concerns, both with the article itself and the BETs process as a
whole. The relative efficacy of adrenaline and vasopressin in the
management of cardiac arrest is an important subject of relevance to all
who work in Emergency Medicine. For this BET to only include those papers
directly comparing vasopressin and adrenaline is to dismiss a large amount
of research published in this area. A very brief search on Medline reveals
a large number of articles looking at this subject, including two recently
published reviews comparing adrenaline and vasopressin,[2,3] not
mentioned by the authors. Surely a topic such as this should be subject to
a formal literature review and meta-analysis, not the “shortcut review”
method advocated by the BETs methodology.
One of the stated aims of the BET methodology is to summarize the
highest level of evidence available.[4] In response to previous
criticisms Professor Mackway-Jones was keen to emphasise that those
undertaking BETs “go to great lengths to ensure that the search strategies
used are highly sensitive” [5] It would appear from this article that
this has not been the case on either count.
Given the above concerns could the Journal Editors confirm whether
the BETS are subject to the same peer review process as other articles in
this journal.
References
(1) Hogg K,Mahu R.Vasopressin or adrenaline in cardiac resuscitation. Emerg Med J 2003;20:467.
(2) Ong ME, Lim SH, Anantharaman V. Intravenous adrenaline or vasopressin
in sudden cardiac arrest: a literature review. Ann Acad Med Singapore
2002 Nov;31(6):785-92.
(3) Nolan JP, De Latorre FJ, Steen PA, Chamberlain DA, Bossaert LL.
Advanced life support drugs: do they really work? Curr Opin Crit Care 2002 Jun;8(3):212-8.
(4) Mackway-Jones K. Towards evidence based emergency medicine: best BETs
from the Manchester Royal Infirmary. Emerg Med J 2003;20:464.
(5) K Mackway-Jones replies. J Accid Emerg Med 1999 16:389.
Nigam and Cutter totally fail to present evidence to justify the
claim that “Welsh emergency vehicles examined exhibited an unacceptable
level of bacterial contamination”.[1]
What is more, a press release from the
editorial team to local newspapers led Madeline Brindley of The Western
Mail to write, “Dirty ambulances infested with huge amounts of harmful
bacteria are carrying seriously ill patients to hos...
Nigam and Cutter totally fail to present evidence to justify the
claim that “Welsh emergency vehicles examined exhibited an unacceptable
level of bacterial contamination”.[1]
What is more, a press release from the
editorial team to local newspapers led Madeline Brindley of The Western
Mail to write, “Dirty ambulances infested with huge amounts of harmful
bacteria are carrying seriously ill patients to hospital in Wales,
according to a report published today. The new research discovered that
even after they have been cleaned, ambulances are still home to
"unacceptable" levels of bacteria.”[2]
The authors make no attempt to quantify levels of bacteria for
organisms that are expected to be present in an environment occupied by
people. Inevitably, steering wheels will be home to Staphylococcus
epidermidis and viridans group streptococci, as they represent normal skin
commensals. Bacillus sp. are ubiquitous environmental organisms.
Similar comments can be levied for all areas sampled throughout the
ambulances.
The method used by Nigam and Cutter is suitable for a qualitative
assessment and is normally used to identify specific pathogens. The only
potential pathogen identified by the study is Staphylococcus aureus. A
quantitative method should have been used for this type of study, if the
conclusions were to be supported. Quantitative methods, such as those
discussed by Roberts et al,[3] take a measured area of a given surface and
allow the number of bacteria to be counted and expressed per square
centimetre. Such a technique allows for the assessment of reduction of
bacterial load after a cleaning process.
Quite reasonably, the press will pick up on stories such as these
when prompted by the editorial team. However, there is a responsibility
on the editorial board of journals, their reviewers and the researchers to
ensure that study methods and the review process are rigorous. Only then
can proper conclusions be drawn. Without that, fear can be instilled in
the patient population and the NHS challenged inappropriately.
References
(1) Nigam Y, Cutter J. A preliminary investigation into bacterial contamination of Welsh emergency ambulances. Emerg Med J 2003;20:479-482.
(3) Enumeration of micro-organisms. In Practical food microbiology: methods for the examination of
foods for micro-organisms of public health significance 2nd Edition, Robers D, Hooper W, Greenwood
M, (Eds). London:
Public Health Laboratory Service, 1995:95-120.
Graber's article raises several valid points about the provision of
diagnostic decision support in the ED.[1] The Emergency Depertment (ED) is one setting where
reaching the correct diagnosis - for simple clinical problems and unusual
ones - may reduce the burden of diagnostic error and its costly adverse
consequences.[2]
In Graber's study, QMR and ILIAD were tested for their diagnostic
accu...
Graber's article raises several valid points about the provision of
diagnostic decision support in the ED.[1] The Emergency Depertment (ED) is one setting where
reaching the correct diagnosis - for simple clinical problems and unusual
ones - may reduce the burden of diagnostic error and its costly adverse
consequences.[2]
In Graber's study, QMR and ILIAD were tested for their diagnostic
accuracy with the limited amount of data available at initial clinical
presentation; quite rightly, the authors used the final diagnosis at
discharge from ED as the gold standard. However, this testing was not
performed by the lay user, and the systems were provided detailed clinical
information derived from multiple physicians' assessment - conditions that
may not be satisfied in real life usage. Despite this, the systems do not
appear to be very useful: in an individual case, their accuracy (compared
to an ED physician) is less than 50%; even if it were 100%, would a user
be able to select the correct diagnosis from the 20-30 diagnoses offered;
and even if they could, do ED physicians have the time to spend 20-40
minutes with these systems for each patient? The authors rightly conclude
that a diagnostic 'reminder' system, rather than a diagnostic oracle,
might serve ED physicians better, a conclusion that has been confirmed in
previous studies of diagnostic decision support.[3]
We have been involved in the development and validation of a
diagnostic reminder system, available free on the Web for pediatrics,
called ISABEL (http://www.isabel.org.uk). It was developed by a UK medical
charity after a 3 year old child suffered a mis-diagnosis in ED.[4,5] We
have circumvented many of the criticisms that Graber et al. raise about
"expert systems" by utilising 4 standard, widely accepted textbooks as the
knowledge base, which are searched by a powerful software (Autonomy) that
uses advanced textual pattern recognition techniques to identify candidate
diagnoses based on clinical features entered by users in free text. Only
10-12 diagnoses are offered, arranged in broad headings of causation
(Toxicology, Cardiology etc.) rather than in order of likelihood. Further
information on each diagnosis is available as text from the textbook.
Demanding, time-pressured ED physicians will be interested by the
fact that ISABEL displayed the final ED diagnosis >85% of the time,
when tested against a sample of 100 children;[6] all the diagnoses
considered to be important in the diagnostic workup of these patients were
displayed by ISABEL in 73% cases; and it took less than 2 minutes for lay
users to enter clinical features in free text and generate meaningful
results. Testing the impact of such a system with real clinicians in a
laboratory setting suggested that in 1 out of every 7 consultations, they
were reminded a 'significant' diagnosis that would otherwise have been
missed. Similar results have been replicated in real life in a recent
multi-centre study in 4 UK paediatric EDs (awaiting publication). The
ISABEL model is also currently being extended to adult medicine.
It seems reasonable to conclude that in the context of an ED, systems
that deliver rapid, practical and easy-to-use diagnostic reminders might
prove more useful than "expert problem-solver" systems that may provide
accurate results, but following lengthy interaction.
References
(1) Graber MA, VanScoy D. How well does decision support software
perform in the emergency department? Emerg Med J 2003;20:426-428.
(2) Leape LL, Brennan TA, Laird N, Lawthers AG, Localio AR, Barnes BA,
Hebert L, Newhouse JP, Weiler PC, Hiatt H. The nature of adverse events in
hospitalized patients. Results of the Harvard Medical Practice Study II. N
Engl J Med 1991 Feb 7;324(6):377-84.
(3) Lemaire JB, Schaefer JP, Martin LA, Faris P, Ainslie MD, Hull RD.
Effectiveness of the Quick Medical Reference as a diagnostic tool. CMAJ
1999 Sep 21;161(6):725-8.
(4) Greenough A. Help from ISABEL for paediatric diagnoses. Lancet 2002 Oct 19;360(9341):1259.
(5) Ramnarayan P, Britto J. Paediatric clinical decision support
systems. Arch Dis Child 2002 Nov;87(5):361-2.
(6) Ramnarayan P, Tomlinson A, Rao A, Coren M, Winrow A, Britto J.
ISABEL: a web-based differential diagnostic aid for paediatrics: results
from an initial performance evaluation. Arch Dis Child 2003;88:408-13.
I welcome the paper by Frampton et al.[1] describing their experiences
of nurse-administered nitrous oxide, which adds further evidence to the
literature [2] supporting this technique as a useful and safe method of
easing the suffering of children during their attendance at an Emergency
Department.
I feel that the use of the term “relative analgesia” is somewhat
confusing; this is not...
I welcome the paper by Frampton et al.[1] describing their experiences
of nurse-administered nitrous oxide, which adds further evidence to the
literature [2] supporting this technique as a useful and safe method of
easing the suffering of children during their attendance at an Emergency
Department.
I feel that the use of the term “relative analgesia” is somewhat
confusing; this is not a term previously encountered in the literature
describing sedative/analgesic techniques. The United States guidance [3, their reference 2] does not use this term when defining sedation levels
nor do the current UK [4,5] and Australasian [6] guidance and definitions. To
introduce a new term may prevent accurate comparisons of techniques in the
literature. Nitrous oxide is known to produce both analgesia and sedation:
in the context of this study it would have been better to describe the
level of sedation according to established definitions so readers can
assess effects, and compare them to other studies.
I would also welcome description of two other outcomes measures which
readers would find important when considering a sedative/analgesic
technique: adequacy of sedation and parent/operator satisfaction. The
authors do describe 10 cases (4.4%) requiring additional sedation but not
whether the remaining children were adequately sedated, or inadequately
sedated but the procedure was completed anyway.
References
(1) Frampton A, Browne GJ, Lam LT, et al. Nurse administered relative
analgesia using high concentration nitrous oxide to facilitate minor
procedures in children in an emergency department.Emerg Med J 2003;20:410-413.
(2) O’Sullivan Í, Benger J. Nitrous Oxide in emergency medicine. Emerg Med J 2003;20:214-217.
(3) American College of Emergency Physicians. Clinical policy for procedural sedation and analgesia in the emergency department. Ann Emerg Med 1998;31:663–77.
(4) UK Academy of Medical Royal Colleges and their Faculties.
Implementing and ensuring Safe Sedation Practice for healthcare procedures in adults.
Report of an Intercollegiate Working Party chaired by the Royal College of
Anaesthetists; The Academy, 2001.
(5) Scottish Intercollegiate Guidelines Network. 2002; guideline 58. http://www.sign.ac.uk/
(Accessed Mar 2003 – now under revision)
(6) Australasian College of Emergency Medicine. Policy Document – Use of
intravenous sedation for procedures in the emergency department. http://www.acem.org.au/open/documents/sedation.htm
(Accessed September 2003).
I read with interest the article by Schull.[1] Having recently moved
back to Trinidad from the UK, I had thought that the problems encountered
by Emergency Departments in developing countries were different from those
in the developed world. Unfortunately, they are all too familiar: overcrowding, long waiting times, lack of inpatient facilities, and
lack of trained staff. Each of these problems differ in d...
I read with interest the article by Schull.[1] Having recently moved
back to Trinidad from the UK, I had thought that the problems encountered
by Emergency Departments in developing countries were different from those
in the developed world. Unfortunately, they are all too familiar: overcrowding, long waiting times, lack of inpatient facilities, and
lack of trained staff. Each of these problems differ in detail and
magnitude, however. In these differences, there may be lessons to be
learnt.
While overcrowding and long waiting times are indeed an issue the
world over, they appear to be less severe in developing countries than in
developed countries. In my own department (a paediatric facility seeing
appoximately 50,000 patients per year) our average waiting time to see a
doctor was recently audited to be less than half an hour. Although the
range was quite large, very few patients waited more than four hours to be
seen. Is this a reflection of good practice or are there other forces at
work? In most departments in Trinidad, staffing is at a very junior level,
with few senior staff. In this situation doctors in the Emergency Room
provide a limited amount of care for patients befor referring them on.
This leads to shorter waiting times, but also less efficiency overall, as
individuals suffer through several referrals up the ladder before
receiving definitive care. This is less so in the paedaitric department,
which is manned by paediatric residents, but much more so in the adult
departments. In these departments, the average waiting time is even less
than that quoted, while the admission rate is much higher (40% for the
adult departments compared to 10% for the children's hospital). Quicker care
is not necessarily better care.
The availability of inpatient facilities and the culture surrounding
this also has an impact on throughput. In most departments in Trinidad.
overcrowding on the wards is acepted as a part of life. Apart from the
children's hospital, patients' admissions to wards are not delayed if the
ward is full. Space is 'made', by accommodating patients two to a bed, or
making room for trolleys. The only areas in which this policy is not
feasible are the critical care areas, including ICU. It is interesting to
note that the availablility of ICU beds is much less than in developing
countries and the waiting times to get one of these beds, as well as the
threshold for admission to ICU is much greater than in developing
countries.
Finally, staffing is a real problem. Most Departments are staffed by
relatively untrained junior staff with no specific interest in Emergency
Medicine. It is difficult to prove how this affects waiting times, but a
small audit of the paediatric emergency room in our hospital suggests that
the presence of senior staff on the shop floor reduces both the admission
rate and the time to be seen. However, it also means that patients stay
longer in the Emergency Department while receiving more comprehensive
care.
In summary, the problems of Emergency Rooms around the world are
similar, but vary in magnitude and detail. Achieving better waiting times
and les overcrownding in the Emergency Room may be at the expense of the
quality of care in the entire system, if managed in isolation.
Reference
(1) Schull MJ. Sex, SARS, and the Holy Grail. Emerg Med J 2003;20:400-401 .
We read with interest the comments on our best evidence topic review on Vasopressin or adrenaline in cardiac resuscitation and are happy to
explain the process involved in producing the BET.
This literature search was first conducted in March 2002. Our
initial and specific question was:
Is vasopressin more effective than
adrenaline in achieving return of circulation and longte...
We read with interest the comments on our best evidence topic review on Vasopressin or adrenaline in cardiac resuscitation and are happy to
explain the process involved in producing the BET.
This literature search was first conducted in March 2002. Our
initial and specific question was:
Is vasopressin more effective than
adrenaline in achieving return of circulation and longterm survival, in human
cardiac arrest?
A full and sensitive search strategy was compiled. The
search strategy was checked by two additional independent doctors who cross
checked their own strategies in order to maximse the sensitivity. All
titles and abstracts were appraised initially by the two authors and prior
to publication by the third independent author. The relevant original
studies and review articles were sourced in full text (18 in total). All
review articles were cross referenced.
These 18 papers were reduced to four potentially relevant papers. This
included the two published studies. The search strategy and all four papers
were reviewed by the Manchester Royal Infirmary Emergency Medicine journal
club. A consensus decision was taken to exclude from the analysis one
study reporting the effects of intravenous vasopressin on coronary
perfusion pressures in 10 patients[1] and a second which reported the
effects of intravenous vasopressin administered in refactory cardiac
arrest, in 8 patients.[2] The first study did not use return of
ciculation as an outcome, and the second did not compare the effects of
vasopressin and adrenaline. The decision to publish this review was
taken four months prior to publication. At that point it was reviewed by
Professor Mackway-Jones, the first author repeated the search and a third
independent author checked the relevant articles and search strategy.
To directly respond to your points
1. The BET addresses a specific question. We did not aim to present
a vague representation of all literature on vasopressin but asked the
question - is vasopressin better than adrenaline in a human cardiac
arrest.
2. Dr Locker wonders why we did not include two recent reviews
addressing this question. A less superficial appraisal of these papers
would have revealed they found the same 4 studies. We have cross
referenced all the review articles published on this subject and can find
no further studies.
3. We do not pretend that these reviews are systematic reviews, (we
used Medline only and do not search for unpublished data), but we do
openly lay out our methodology. It would be possible for another doctor,
anywhere in the world, to repeat this search exactly if they so required.
4. At present, a meta-analysis would appear wholly inappropriate to
answer this question. There are only two small studies, the results of
which are clearly laid out in the table. The reader is capable of drawing
their own conclusions from this table. When more relevant data is
available (there are at least two ongoing studies), a meta-analysis may be
of use.
In conclusion, this BET is an accurate and reproducible formal
review. It addresses the question posed by the authors and clearly
summarises the relevant published literature.
References
(1) Morris DC. Dereczyk BE. Grzybowski M. Martin GB. Rivers EP.
Wortsman J. Amico JA. Vasopressin can increase coronary perfusion pressure
during human cardiopulmonary resuscitation Academic Emergency Medicine.
4(9):878-83, 1997 Sep.
(2) Lindner KH. Prengel AW. Brinkmann A. Strohmenger HU. Lindner IM. Lurie KG. Vasopressin administration in refractory cardiac arrest.
Annals of Internal Medicine. 124(12):1061-4, 1996 Jun 15.
With reference to the comments made by Dr Simmons [1] concerning 'A
preliminary investigation into bacterial contamination of Welsh emergency
ambulances'.[2] We fully accept that the methods used were not rigorous
enough to accurately quantify numbers of bacteria for any given measured
area. However, our work was simply described as a preliminary
investigation and this pilot study did identify short...
With reference to the comments made by Dr Simmons [1] concerning 'A
preliminary investigation into bacterial contamination of Welsh emergency
ambulances'.[2] We fully accept that the methods used were not rigorous
enough to accurately quantify numbers of bacteria for any given measured
area. However, our work was simply described as a preliminary
investigation and this pilot study did identify shortfalls in cleaning
practices in use at the time of the study. These included a lack of
designated cleaning equipment for ambulances, insufficient time for
thorough cleaning and lack of suitable decontamination processes for
medical equipment.
The majority of organisms identified in the study were unlikely to
pose any threat of infection to patients or ambulance personnel. This was
clearly stated in our article, but sadly was often ignored in the
subsequent press reports, resulting in public concern.
Having identified that there were shortfalls in cleaning practices,
action was required.
The Welsh Ambulance Trust responded immediately to the results of the
study and, supported by one of the authors (JC), took action to improve
standards of cleanliness. This included the following:
The Infection Control Committee and Regional Infection Control
Teams continue to monitor cleanliness through regular environmental
audits;
Colour coded cleaning equipment has been introduced to prevent cross
contamination during cleaning and standardisation of detergents and
disinfectants has been completed;
All vehicles have now been provided with ‘spillage kits’ to absorb fluid
spills;
A chlorine releasing disinfectant is provided for each vehicle for
prompt decontamination of blood and body fluids;
Significant investment has been made to replace re-usable medical
equipment e.g. Entonox masks and suction canisters with disposable
alternatives. Disposable covers are provided for laryngoscope blades and
single use bougies for intubation have been supplied;
Infection control training is provided during all patient transport
services and emergency technician training courses in which the importance
of cleaning is included.
References
(1) Simmons MD Steering wheel spin? [electronic response to Nigam and Cutter; A preliminary investigation into bacterial contamination of Welsh emergency ambulances]
emjonline.com 2003http://emj.bmjjournals.com/cgi/eletters/20/5/479#143
(2) Nigam Y, Cutter J. A preliminary investigation into bacterial
contamination of Welsh emergency ambulances. Emer Med J 2003; 20:479-482.
Howes [1] concern about the term !%relative analgesia!& pertaining to
our recent description of nitrous oxide analgesia in children is noted.[2] This is actually a term that has been used to describe nitrous oxide
analgesia for many years. It first appeared in the dental literature and
was used originally to describe situations where continuous flow /
variable concentration nitrous oxide was administ...
Howes [1] concern about the term !%relative analgesia!& pertaining to
our recent description of nitrous oxide analgesia in children is noted.[2] This is actually a term that has been used to describe nitrous oxide
analgesia for many years. It first appeared in the dental literature and
was used originally to describe situations where continuous flow /
variable concentration nitrous oxide was administered, often via a nasal
mask.[3-7] Other authors looking at the risk of aspiration using nitrous
oxide analgesia used the term !%relative analgesia!& when studying 50%
nitrous oxide / oxygen (Entonox).[8,9] The term does not appear to have
been used in any of the emergency medicine literature pertaining to
nitrous oxide that we have seen.
The term continues to be used in contemporary literature [10,11] and
in 2001 Lahoud et al [12] described relative analgesia as having three
elements:
patient remaining conscious
deliver 100% O2 if needed.
Certainly we found in our study [2] that distraction techniques are easily
done in conjunction with this method of analgesia and form an important
part of it.
We have used the term "relative analgesia" (RA) in our institution for
many years which is why it was included in our study. The term has also
persisted in the name of the equipment used to administer continuous flow
/ variable concentration with the Quantiflex RA machine originally being
manufactured by Cyprane Ltd, Keighley, England and now by Matrix Medical,
New York.
We agree with Howe that there is enough confusion in the semantics of
the literature on sedation / analgesic techniques without rejuvenating old
terminology. However perhaps the term !%relative analgesia!and may be useful
in describing analgesia by inhalational techniques alone which are
becoming more common using agents such as nitrous oxide, methoxyflurane
and nitrous oxide / sevoflurane mixtures.[13] Nitrous oxide provides
analgesia, anxiolysis and mild amnesia obtained with maintenance of verbal
contact and predominantly intact laryngeal reflexes. No other single agent
does this.
References
(1) Howes MC. What is !'relative analgesia!( ? Emerg Med J 2003; 20:
(2) Frampton A, Browne GJ, Lam LT, Cooper MG, Lane LJ. Nurse
administered relative analgesia using high concentration nitrous oxide to
facilitate minor procedures in children in an emergency department. Emerg
Med J 2003; 20: 410-413
(3) Langa H: Relative analgesia in dental practice: inhalation
analgesia with nitrous oxide. Philadelphia: WB Saunders Co, 1968, p164.
(4) Roberts GJ, Wignall BK. Efficacy of the laryngeal reflex during
oxygen-nitrous oxide sedation (Relative Analgesia). British J of
Anaesthesia 1982; 54: 1277-1281
(5) Nishino T, Takizawa K, Yokokawa N, Hiraga K. Depression of the
swallowing reflex during sedation and/or relative analgesia produced by
inhalation of nitrous oxide in oxygen. Anesthesiology 1987; 67: 995-998
(6) Roberts GJ, Gibson A, Porter J, Zoysa S. Relative analgesia: an
evaluation of the efficacy and safety. Br Dent J 1979; 146: 177-82.
(7) Pleasants J. The case against relative analgesia. Dent Clin North
Am 1971; 14: 839-847
(8) Cleaton-Jones P. The laryngeal-closure reflex and nitrous oxide -
oxygen analgesia. Anesthesiology 1976; 45: 569-570.
(9) Rubin J, Brock-Utne JG, Greenberg M, Bortz J, Downing JW.
Laryngeal incompetence during experimental !%relative analgesia!& using
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(10) Roberts GJ. Inhalation sedation (relative analgesia) with oxygen
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(12) Lahoud GYG, Averley PA, Hanlon MR. Sevoflurane inhalation
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To the Editor!
We have read the original contribution by Sutcu Cicek et al. [1] with high interest regarding the effect of nail polish and henna on pulse oximetry readings. In their study, these authors report on the influence of both factors in 33 normoxic healthy females. Although the study is interesting, it has significant limitations, which must be addressed.
To our surprise, the authors state, it is not proven that nail polish effects the accuracy of pulse oximeters [1]. However, several randomized, controlled trials with both healthy persons and critically ill patients report on the effect of nail polish on oxygen saturation measured by pulse oximetry [2, 3, 4]. Interestingly, some of these studies have been cited by the authors themselves.
Sample size calculation prior to beginning of a trial is obligate to determine the significance of results. Unfortunately, in this trial an adequate mathematical sample size calculation was obviously waived. Therefore, results of the present study cannot be interpreted regarding both the statistical significance and the clinical relevance.
To determine pulse oximetry accuracy, intermittent arterial blood gas analyses (ABGA) are essential [3]. However, accuracy in the present study was only determined by consecutive pulse oximeter measurements over a specific duration, which may alter pulse oximetry readings. A major limitation of the present study is that accuracy is not analyzed in the present study al...
Show MoreDear Editor
The articles on the problems of Emergency Department (ED) overcrowding make interesting reading, as the problems outlined are familiar to us in the UK, and I am sure that we would all identify similar causes and both short and long term solutions.[1]
The list of stopgap measures, in the article by Fatovich and Hirsch [1] is also familiar to us all. Ambulance diversion is difficult outside larg...
Dear Editor
The best evidence topic report (BET) by Hogg and Mahu [1] raises a number of concerns, both with the article itself and the BETs process as a whole. The relative efficacy of adrenaline and vasopressin in the management of cardiac arrest is an important subject of relevance to all who work in Emergency Medicine. For this BET to only include those papers directly comparing vasopressin and adrenaline is to...
Dear Editor
Nigam and Cutter totally fail to present evidence to justify the claim that “Welsh emergency vehicles examined exhibited an unacceptable level of bacterial contamination”.[1] What is more, a press release from the editorial team to local newspapers led Madeline Brindley of The Western Mail to write, “Dirty ambulances infested with huge amounts of harmful bacteria are carrying seriously ill patients to hos...
Dear Editor
Graber's article raises several valid points about the provision of diagnostic decision support in the ED.[1] The Emergency Depertment (ED) is one setting where reaching the correct diagnosis - for simple clinical problems and unusual ones - may reduce the burden of diagnostic error and its costly adverse consequences.[2]
In Graber's study, QMR and ILIAD were tested for their diagnostic accu...
Dear Editor
I welcome the paper by Frampton et al.[1] describing their experiences of nurse-administered nitrous oxide, which adds further evidence to the literature [2] supporting this technique as a useful and safe method of easing the suffering of children during their attendance at an Emergency Department.
I feel that the use of the term “relative analgesia” is somewhat confusing; this is not...
Dear EDitor
I read with interest the article by Schull.[1] Having recently moved back to Trinidad from the UK, I had thought that the problems encountered by Emergency Departments in developing countries were different from those in the developed world. Unfortunately, they are all too familiar: overcrowding, long waiting times, lack of inpatient facilities, and lack of trained staff. Each of these problems differ in d...
Dear Editor
We read with interest the comments on our best evidence topic review on Vasopressin or adrenaline in cardiac resuscitation and are happy to explain the process involved in producing the BET.
This literature search was first conducted in March 2002. Our initial and specific question was:
Is vasopressin more effective than adrenaline in achieving return of circulation and longte...
Dear Editor
With reference to the comments made by Dr Simmons [1] concerning 'A preliminary investigation into bacterial contamination of Welsh emergency ambulances'.[2] We fully accept that the methods used were not rigorous enough to accurately quantify numbers of bacteria for any given measured area. However, our work was simply described as a preliminary investigation and this pilot study did identify short...
Dear Editor
Howes [1] concern about the term !%relative analgesia!& pertaining to our recent description of nitrous oxide analgesia in children is noted.[2] This is actually a term that has been used to describe nitrous oxide analgesia for many years. It first appeared in the dental literature and was used originally to describe situations where continuous flow / variable concentration nitrous oxide was administ...
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