Bredmose et al. have published an excellent indictment for the use of
ketamine in the pre-hospital phase; a study of 1030 patients is
impressive.(1)
Mountain Rescue is a small specialist area of pre-hospital care where many
physicians have acknowledged the benefits of ketamine for many years.(2)
Its
versatility and, with careful use, its ability to dissociate analgesia
from airway
compromise are...
Bredmose et al. have published an excellent indictment for the use of
ketamine in the pre-hospital phase; a study of 1030 patients is
impressive.(1)
Mountain Rescue is a small specialist area of pre-hospital care where many
physicians have acknowledged the benefits of ketamine for many years.(2)
Its
versatility and, with careful use, its ability to dissociate analgesia
from airway
compromise are particularly appealing. For example, having to use simple
airway adjuncts after the administration of a drug will frequently prelude
many of the rapid extrication techniques such as helicopter winching that
the
patient desperately requires. The risks of ‘escalating’ to intubation, for
example at subzero temperatures with patient’s half buried in snow on a
45º
ice slope or 20 metres down a crevasse requires careful consideration.
A few additional points are worth noting:
a) Intranasal S-ketamine (~2mg/kg) has its advocates in extreme conditions
where parenteral access is impossible though concerns remain on
reproducibility of effect.(3,4) High intranasal doses can produce high
plasma
concentrations of ketamine. However, the amount swallowed varies and leads
to a high variability of effect.(5)
b) Bredmose et al. report ~100 patients sedated with midazolam >5
mg.(1)
We warn against using excessive midazolam doses for sedation, as this may
impair upper airway control. In our practice 1-3 mg i.v. is sufficient to
sedate
adults for up to one hour. As in this study, most mountain rescue
physicians
routinely use midazolam and rarely see emergence phenomena. However,
they do occur and may require additional midazolam particularly if
helicopter
evacuation is imminent.
c) In many countries, ‘ketamine’ is S-ketamine – the active S-enantiomer
unlike the racaemic mixture of R- and S-ketamine used in the UK.(6)
Therefore practitioners elsewhere may need to reduce (up to a fourth) the
doses quoted.(6)
d) In patients with traumatic brain injury, the use of ketamine is still
controversial though many mountain rescue physicians use it in preference
to
other induction agents in the mountain setting.(7)
e) As of January 2006, Ketamine became a Controlled Drug in the UK under
the Misuse of Drugs Act. (It has been controlled in many other countries
for
years.) As a schedule 4 part I drug, it does not require the physician to
keep a
Controlled Drug register nor obey the safe custody criteria of a schedule
2
drug but non-NHS organisations will require a Home Office Licence to
possess it.
Dr John Ellerton
General Practitioner, Penrith Health Centre, Penrith, Cumbria. CA11
7UL UK
and Medical Officer, Mountain Rescue Council
Dr Peter Paal
Department of Anesthesiology and Critical Care Medicine, Innsbruck
Medical
University, Anichstrasse 35, A-6020 Innsbruck, Austria
Dr Hermann Brugger
Associate Professor at the Innsbruck Medical University, Austria and
President
of ICAR MEDCOM, Europastrasse 17, I-39031 Bruneck, Italy
References
1) Bredmose PP, Lockey DJ, Grier G, et al. Pre-hospital use of
ketamine for
analgesia and procedural sedation. Emerg Med J 2009;26:62-4.
2) Thomas A, Wiget U, Rammlmair G. Treatment of pain in the field.
ICAR
recommendation No. 10. In Elsensohn F, ed. ICAR recommendations, 1999.
p55-7. http://www.ikar-cisa.org/ikar-cisa/documents/2007/
RECM0010E.pdf.
3) http://www.wolfetory.com/nasal.php.
4) Weber F, Wulf H, Gruber M, et al. S-ketamine and s-norketamine
plasma
concen-trations after nasal and i.v. administration in anesthetized
children.
Paediatr Anaesth 2004;14:983-8.
5) Malinovsky JM, Servin F, Cozian A, et al. Ketamine and norketamine
plasma concentrations after i.v., nasal and rectal administration in
children.
Br J Anaesth. 1996 Aug;77(2):203-7.
6) http://en.wikipedia.org/wiki/Ketamine.
7) Gunning M, Perkins Z, Quinn T. Trench entrapment: is ketamine safe
to
use for sedation in head injury? Emerg Med J 2007;24:794-5.
A survey in the North West of England found a rate of 20% self-
reported use of "poppers"( inhaled amyl nitrates) among 16 year olds
(www.drugscope.org.uk).
In the United Kingdom, amyl nitrite is controlled under the
"Medicines Control Act" Although possession is legal supplying may be an
offence. Other nitrites are readily available in consumer products such as
room odorants and leather cleaner....
A survey in the North West of England found a rate of 20% self-
reported use of "poppers"( inhaled amyl nitrates) among 16 year olds
(www.drugscope.org.uk).
In the United Kingdom, amyl nitrite is controlled under the
"Medicines Control Act" Although possession is legal supplying may be an
offence. Other nitrites are readily available in consumer products such as
room odorants and leather cleaner. Numerous shops, particularly sex shops,
clubs, and shops selling drug paraphernalia sell nitrites as "room aromas"
or similar.
There are a few more points that are useful in the evaluation and
management of methemoglobinemia:
(1) Methemoglobinemia should be suspected in a “blue breathless
patient unresponsive to oxygen" and when there is presence of a
"saturation gap" (The SaO2 in arterial blood is a calculated value based
on the partial pressure of dissolved oxygen and assumes that no abnormal
oxygen is present. Therefore the reported oxygen saturation from the
laboratory is generally higher than the SpO2 measured with the pulse
oximetry, hence accounting for a “saturation gap” (reference 1)
(2) Methylene blue interferes with the accurate measurement of
methemoglobin by co-oximetry. Therefore, following methylene blue
administration co-oximetry cannot be used to monitor methemoglobin levels.
In addition, methylene blue is most effective in intact erythrocytes;
efficacy is reduced in the presence of haemolysis. Moreover, in the
presence of haemolysis, high dose methylene blue (20-30 mg/kg) can itself
initiate methaemoglobin formation (reference 2)
(3) Methylene blue is an oxidant; its metabolic product
leukomethylene blue is the reducing agent. Therefore, large doses of
methylene blue may result in higher levels of methylene blue rather than
the leukomethylene blue, which will result in hemolysis and,
paradoxically, methemoglobinemia in patients with glucose-6-phosphate
dehydrogenase (G6PD) deficiency ( reference 4)
(4) When methylene blue treatment fails to eliminate cyanosis the
patient may be deficient in G-6-PDH (prevalent in 10% of African-
Americans) or NADPH reductase. In such cases transfusion / exchange
transfusion should be considered(reference 4)
(5) Dextrose should be given because the major source of NADH in the
red blood cells is the catabolism of sugar through glycolysis. Dextrose is
also necessary to form NADPH through the hexose monophosphate shunt, which
is necessary for methylene blue to be effective (reference 3)
(6) Some drugs, such as dapsone, benzocaine, and aniline, produce a
rebound methemoglobinemia, in which methemoglobin levels increase 4 to 12
hours after successful methylene blue therapy (reference 5)
References:
1. J Emerg Med. 2007 Aug;33(2):131-2: Mind the gap.
2. Toxicol Rev. 2003;22(1):13-27:Occupational methaemoglobinaemia,
Mechanisms of production,features, diagnosis and management including the
use of methylene blue
3. Eur J Biochem. 1970 Jan;12(1):24-30: Regulatory factors
in methylene blue catalysis in erythrocytes.
4. Br J Haematol. 1983 May;54(1):29-41:Studies of the
efficacy and potential hazards of methylene blue therapy in aniline-
induced methaemoglobinaemia
5. N Engl J Med. 1991 Jan 17;324(3):169-74: Glucose-6-
phosphate dehydrogenase deficiency
We read with interest the recent article by Mathieu et al on the use
of
propofol as an effective sedative for relocating hip prosthesis (1). We
would
like however, to draw attention to several areas of concern.
The authors administered doses of propofol up to 2 mg/kg. This is an
anaesthesia-inducing dose of propofol, rightly recognised in the
discussion.
The fact that patients were not rou...
We read with interest the recent article by Mathieu et al on the use
of
propofol as an effective sedative for relocating hip prosthesis (1). We
would
like however, to draw attention to several areas of concern.
The authors administered doses of propofol up to 2 mg/kg. This is an
anaesthesia-inducing dose of propofol, rightly recognised in the
discussion.
The fact that patients were not routinely starved prior to their procedure
is of
concern. We may assume, as eight patients experienced airway or
ventilatory
complications, these patients were unable to protect their airway from
pulmonary aspiration. In addition, the prior use of morphine and the
experience of pain would both increase the risk of delayed gastric
emptying
and subsequent aspiration.
The description of propofol as an ‘ultra-short acting agent’ is
misleading. It
indeed has a shorter termination half-life than midazolam. Once apnoea has
occurred though, time to return of spontaneous ventilation can be
unpredictable and severe hypoxia can occur even in pre-oxygenated
patients. It should also be noted there is no propofol antagonist should
complications occur.
Finally, the authors conclude that the incidence of significant
adverse effects
was uncommon, but they quote a rate of 12% (12/98). The Royal College of
Anaesthetists consider a complication rate of greater than 10% as very
common (2). With such a high complication rate, it is hard to justify the
use of
this technique by practitioners other than those with anaesthetic or
advanced
airway training.
We feel, it would be unwise to consider this practice safe and we
would
recommend further discussions with anaesthetic colleagues before this
practice is widely implemented.
Yours faithfully
Dr Marc Davison, Consultant Anaesthetist, Buckinghamshire Hospitals
NHS
Trust
Dr Richard Stewart, Specialist Registrar in Anaesthetics, Oxford
Rotation
References
1) N Mathieu, L Jones, A Harris, et al. Is Propofol a safe and
effective
sedative for relocating hip prostheses? Emerg Med J 2009;26:37-38
2) Royal College of Anaesthetists. You and your anaesthetic. Third
edition
May 2008.
In his letter, Fayomi states correctly that the use of beta-blockers
in the management of cocaine-related acute coronary syndrome is
contraindicated (1). We feel, however, that Fayomi has mis-interpreted
the information in Table 1, by believing that the authors are advocating
the use of beta-blockers in the management of cocaine-related chest pain.
The authors have clearly highlighted in the first...
In his letter, Fayomi states correctly that the use of beta-blockers
in the management of cocaine-related acute coronary syndrome is
contraindicated (1). We feel, however, that Fayomi has mis-interpreted
the information in Table 1, by believing that the authors are advocating
the use of beta-blockers in the management of cocaine-related chest pain.
The authors have clearly highlighted in the first paragraph on page 823 of
the manuscript, that the use of beta-blockers in the management of cocaine
-related chest pain (2). The authors have also stated this in other work
that they have published relating to cocaine-related chest pain and other
cocaine-related toxicity (3,4,5).
For each of the clinical scenarios in table 1, those participating in
the study were asked to state if the antidote/treatment and route of
administration were correct; for some of the scenarios an inappropriate
antidote/treatment and/or route of administration was stated. Those
participating scored a correct mark for those scenarios where the
antidote/treatment and/or route of administration was incorrect if they
correctly identified this. The scenario of cocaine-related chest pain and
the suggested antidote/treatment of IV Metoprolol was one of the scenarios
in Table 1 in which an inappropriate antidote/treatment was suggested, and
therefore the correct answer for this scenario was for participants to
state that this was incorrect.
References:
1. Fayomi O. Management of Cocaine Associated Chest Pain. EMJ on line
http://emj.bmj.com/cgi/eletters/25/12/820 (last accessed 23rd December
2008).
2. Lidder S, Ovaska H, Archer JR, Greene SL, Jones AL, Dargan PI,
Wood DM. Doctors' knowledge of the appropriate use and route of
administration of antidotes in the management of recreational drug
toxicity. Emerg Med J. 2008; 25: 820-3
3. Wood DM, Hill D, Gunasekera A, Greene SL, Jones AL, Dargan PI. Is
cocaine use recognised as a risk factor for acute coronary syndrome by
doctors in the UK? Postgrad Med J. 2007; 83: 325-8
4. Greene SL, Dargan PI, Jones AL. Acute poisoning: understanding 90%
of cases in a nutshell. Postgrad Med J. 2005; 81: 204-16.
5. Wood DM, Dargan PI, Hoffman RS. Management of cocaine-induced
cardiac arrhythmias due to cardiac ion channel dysfunction. Clin Toxicol
(Phila). 2008 Sep 24:1-10. [Epub ahead of print]
I have read excerpts form you article “ Police Use Excessive Force,
ER Docs Say” January 1 2009, Volume 26, Issue 1 . Although I haven’t read
the whole article, I do believe your study is flawed. For the purposes of
this study, how did you define excessive force? Did you allow the
individual doctors to subjectively define the term excessive force. Law
enforcement officers are autho...
I have read excerpts form you article “ Police Use Excessive Force,
ER Docs Say” January 1 2009, Volume 26, Issue 1 . Although I haven’t read
the whole article, I do believe your study is flawed. For the purposes of
this study, how did you define excessive force? Did you allow the
individual doctors to subjectively define the term excessive force. Law
enforcement officers are authorized to use force in apprehending a
criminal. The definition of justifiable force employed by most agencies is
minimum amount force necessary to effect a lawful arrest. This is a very
easy definition when you have a compliant person who doesn’t resist. What
about when the person does resists? Tries to assault the officer? If an
officer defends himself from that assault and injures the criminal, what
do you think the criminal is going to say to the ER personnel? I don’t
think you will hear the criminal say “I violently resisted being arrested
and tried to assault the officer” rather I believe you will here “The
officer hit me for no reason.” There are an infinite amount of variables
that determine the minimum amount of force used in the field all of which
the ER staff is not privy to. An unintentional false allegation based upon
what the criminal tells the doctor can stall a dedicated officers career,
preventing promotions and pay raises. If the patient feels they are the
victim of excessive police force, there are many legal routes for them to
file a complaint. The role of the ER staff is not to judge if there is a
victim of suspected excessive police force, but to treat and document the
patient’s injuries. If the patient files a complaint, those records will
without a doubt be subpoenaed.
As for the handcuffs, they are not constructed to be “user friendly”.
They are made to ratchet closed. If the handcuffs are not double locked,
the prisoner themselves can make them tighter either accidentally or
intentionally. Prisoners have been known to tighten the handcuffs to
bolster there claim of excessive force. Even if the handcuffs are double
locked, the radius and ulna can be pinched in the oval open of the
handcuffs causing pain and making it look like they are too tight. This is
caused by the prisoner trying to move around in the handcuffs and trying
to slip out of them.
Dear Editor,
Bredmose et al. have published an excellent indictment for the use of ketamine in the pre-hospital phase; a study of 1030 patients is impressive.(1) Mountain Rescue is a small specialist area of pre-hospital care where many physicians have acknowledged the benefits of ketamine for many years.(2) Its versatility and, with careful use, its ability to dissociate analgesia from airway compromise are...
A survey in the North West of England found a rate of 20% self- reported use of "poppers"( inhaled amyl nitrates) among 16 year olds (www.drugscope.org.uk).
In the United Kingdom, amyl nitrite is controlled under the "Medicines Control Act" Although possession is legal supplying may be an offence. Other nitrites are readily available in consumer products such as room odorants and leather cleaner....
Dear Sir,
We read with interest the recent article by Mathieu et al on the use of propofol as an effective sedative for relocating hip prosthesis (1). We would like however, to draw attention to several areas of concern.
The authors administered doses of propofol up to 2 mg/kg. This is an anaesthesia-inducing dose of propofol, rightly recognised in the discussion. The fact that patients were not rou...
Dear Editor,
In his letter, Fayomi states correctly that the use of beta-blockers in the management of cocaine-related acute coronary syndrome is contraindicated (1). We feel, however, that Fayomi has mis-interpreted the information in Table 1, by believing that the authors are advocating the use of beta-blockers in the management of cocaine-related chest pain. The authors have clearly highlighted in the first...
To Distinguished Physicians,
I have read excerpts form you article “ Police Use Excessive Force, ER Docs Say” January 1 2009, Volume 26, Issue 1 . Although I haven’t read the whole article, I do believe your study is flawed. For the purposes of this study, how did you define excessive force? Did you allow the individual doctors to subjectively define the term excessive force. Law enforcement officers are autho...
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