Short communication

Successful intraosseous infusion in the critically ill patient does notrequire a medullary cavity

Gerard McCarthy a, Cathal O’Donnell a,*, Moira O’Brien b

a Department of Emergency Medicine, Cork University Hospital, Wilton, Cork, Irelandb Department of Anatomy, Trinity College, Dublin 2, Ireland

Received 21 June 2002; received in revised form 10 July 2002; accepted 16 September 2002

Abstract

Objectives: To demonstrate that successful intraosseous infusion in critically ill patients does not require bone that contains a

medullary cavity. Design: Infusion of methyl green dye via standard intraosseous needles into bones without medullary cavity*/in

this case calcaneus and radial styloid*/in cadaveric specimens. Setting: University department of anatomy. Participants: Two adult

cadaveric specimens. Main outcome measures: Observation of methyl green dye in peripheral veins of the limb in which the

intraosseous infusion was performed. Results: Methyl green dye was observed in peripheral veins of the chosen limb in five out of

eight intraosseous infusions into bones without medullary cavity-calcaneus and radial styloid. Conclusions: Successful intraosseous

infusion does not always require injection into a bone with a medullary cavity. Practitioners attempting intraosseous access on

critically ill patients in the emergency department or prehospital setting need not restrict themselves to such bones. Calcaneus and

radial styloid are both an acceptable alternative to traditional recommended sites.

# 2002 Elsevier Science Ireland Ltd. All rights reserved.

Keywords: Intraosseous; Intraosseous infusion; Emergency treatment; Anatomy

Resumo

Objectivos: Demonstrar que a perfusao intra-ossea eficaz em doentes crıticos nao necessita de ossos com cavidade medular.

Modelo: Perfusao de corante verde de metil em ossos de cadaver sem cavidade medular*/neste caso o calcaneo e estiloide radial.

Ambiente: Departamento de anatomia da universidade. Participantes: Dois cadaveres de adultos. Medida principal de resultados:

Observacao de corante verde de metil em veias perifericas do membro em que foi feita a perfusao intra-ossea. Resultados: Observou-

se o verde de metil nas veias perifericas do membro escolhido em cinco de oito perfusoes intra-osseas em ossos sem cavidade

medular*/calcaneo e estiloide radial. Conclusoes: A perfusao intra-ossea pode ser eficaz em ossos sem cavidade medular. O acesso

intra-osseo em doentes crıticos no departamento de emergencia ou no ambiente pre-hospitalar nao precisa de se restringir a esses

ossos. O calcaneo e a estiloide radial sao alternativas aceitaveis aos locais tradicionalmente recomendados.

# 2002 Elsevier Science Ireland Ltd. All rights reserved.

Palavras chave: Intraosseo; Infusao intraossea; Tratamento emergente; Anatomia

Resumen

Objetivos : Demostrar que la infusion intraosea exitosa en pacientes crıticamente enfermos no requiere hueso que tenga cavidad

medular. Diseno : Infusion de tinta verde de metilo a traves de agujas intraoseas estandar hacia huesos sin cavidad medular*/en este

caso el calcaneo y el estiloides radial- en especımenes cadavericos. Ambiente : Departamento de anatomıa de Universidad.

Participantes : Dos cadaveres de adultos. Principales medidas de resultado : Observacion de tincion de verde de metilo en venas

perifericas de la extremidad en la que se realizo la infusion intraosea. Resultados : Se observo la tintura verde en las venas perifericas

* Corresponding author. Tel.: �/353-21-454-6400.

E-mail address: codonnell@eircom.net (C. O’Donnell).

Resuscitation 56 (2003) 183�/186

www.elsevier.com/locate/resuscitation

0300-9572/02/$ - see front matter # 2002 Elsevier Science Ireland Ltd. All rights reserved.

PII: S 0 3 0 0 - 9 5 7 2 ( 0 2 ) 0 0 3 4 8 - 9

de la extremidad elegida en 5 de 8 infusiones intraoseas en huesos sin cavidad medular*/calcaneo y estiloides radial. Conclusiones :

Infusion intraosea exitosa no siempre requiere inyeccion en hueso con cavidad medular. Los practicantes que intentan acceso

intraoseo en pacientes crıticamente enfermos en el departamento de emergencias o en el ambiente prehospitalario no necesitan

restringirse a esos huesos. El calcaneo y la estiloides radial son alternativas aceptables a los sitios tradicionalmente recomendados.

# 2002 Elsevier Science Ireland Ltd. All rights reserved.

Palabras clave: Intraoseo; Infusion intraosea; Tratamiento de emergencia; Anatomıa

1. Introduction

Intraosseous access is recommended in critically ill

children in whom intravenous access has proved un-

successful [1]. It has recently been reported that thetechnique can also work in adults [2]. Early descriptions

of the technique have implied the presence of a

functioning marrow cavity as an essential prerequisite

for success [3]. Recent guidelines from the European

Resuscitation Council state ‘An intraosseous cannula

provides access to a noncollapsible marrow venous

plexus, which serves as a rapid safe and reliable route

for administration of drugs, crystalloids, colloids, andblood during resuscitation’ [4]. One of the authors has

described the successful use of the calcaneus for

intraosseous infusion in a single paediatric case [5].

This questions the requirement for a functioning me-

dullary cavity for successful intraosseous access. The

following experiment was conducted to test the theory

that the insertion of an intraosseous needle into a bone

that does not have a marrow cavity is sufficient to gaincirculatory access.

2. Materials and methods

The study was performed in a university department

of anatomy using two adult cadavers previously used for

undergraduate medical student anatomy instruction.Intraosseous needles were inserted bilaterally into the

calcanei and distal radii of both cadavers. The site of

insertion into the calcaneus was the anterior portion of

the medial tubercle at the junction of the inferior and

medial surfaces. The site of insertion into the distal

radius was into the radial aspect of the base of the

styloid process.

A 14-gauge Dieckmann intraosseous infusion needlewith a 458 trocar (William Cook, Europe) was used each

time. A total of 5 ml of methyl green dye (at a

concentration of 10 mg/ml) was injected through each

needle.

3. Results

Eight insertion sites were tried on two cadavers*/four

radial styloids and four calcanei. Five out of eight were

successful in showing the immediate passage of dye from

the intraosseous site to adjacent superficial veins. One of

the failures was due to technical error and two had no

obvious reason for failure (Tables 1 and 2).

4. Discussion

Intraosseous access was first described in the early

part of the last century [3,6]. Its recommended use is

currently restricted to critically ill children B/6 years of

age in whom intravenous access has failed [1]. Current

belief is that intraosseous access is only possible in bones

with a functioning medullary cavity. A recent review of

intraosseous vascular access has questioned the need for

red marrow for successful intraosseous infusion [7], but

this was not referenced and we can find no published

evidence other than our own work. Sites traditionally

recommended include proximal and distal tibia, distal

femur, iliac crest and sternum. Each of these sites is

either vulnerable to significant lower limb or pelvic

trauma or at high risk of complications (underlying

cardiac or great vessel damage) in the highly charged

environment of difficult emergency circulatory access. If

one is not limited to bone with a medullary cavity, then

each of the above difficulties may be overcome. Calca-

neus and radial styloid are composed of cancellous

bone. Cancellous bone has an open trabecular structure

similar to the medullary cavity of long bones [8], which

may explain why fluid infusion to these sites, as

demonstrated in our experiment, was successful.

Table 1

Cadaver A

Anatomical site Observation

Right

calcaneus

Dye was immediately observed in the long

saphenous vein continuously from the

medial malleolus to mid tibial level

Left calcaneus Dye was immediately observed to extravasate

from the deep veins at mid-calf level*

Right radial

styloid

Dye immediately observed to extravasate

from veins along the midshaft of radius*

Left radial

styloid

Unsuccessful-dye leaked back from the

insertion site around the intraosseous needle

* We presume this resulted from accidental damage to vessels from

previous dissection.

G. McCarthy et al. / Resuscitation 56 (2003) 183�/186184

Exchanges on Acad-AE-Med, an emergency medicine

internet discussion group (http://www.mailbase.ac.uk/

lists/acad-ae-med/), have indicated that the difficulty

with penetrating the tibia that led to one of the authors

resorting to the calcaneus was not an isolated incident.

In these circumstances, the use of a bone that may be

easier to penetrate (the calcaneus) may be a way out of

this situation.

We did not compare our proposed method with

conventional sites of intraosseous infusion. Standard

intraosseous injection into bones with medullary cavity

has been shown to be successful many times over and is an

accepted resuscitative technique. We do not seek to

abandon these sites, simply to show that if intraosseous

infusion at these sites is unsuccessful or impractical, then

bones without medullary cavity may also allow intraoss-

eous access.

In our experiment, an injection of 5 ml of methyl

green dye to bones lacking a medullary cavity resulted in

dye reaching the veins of the mid calf and the mid

forearm. While this might seem a long distance for a

small volume of dye, most of the lumen of these vessels

was taken up with clotted blood so that the functional

lumen of these vessels was quite small.

If one accepts the premise that intraosseous infusion

to bones without medullary cavity is possible, then two

very important changes to current thinking on vascular

access follow. Firstly, in the resuscitation of the critically

ill child, practitioners are not restricted to a number of

defined bones, but can choose the bone most accessible

in each particular clinical scenario. Secondly, the

technique of intraosseous access does not need to be

restricted to children (who have bones with functioning

medullary cavity), but can be used in adults (who do

not). Thus, the indications for intraosseous access are

much broader than has been accepted to date.

The potential increased applications of this technique

may prove to be of particular benefit in the prehospital

setting. In situations of prolonged extrication times,

poor visibility or difficult physical access to the en-

trapped patient, establishing prompt intravenous access

is often problematic.

Rapid insertion of an intraosseous needle to whatever

bone is most accessible in an individual prehospitalsetting, allowing emergency fluid resuscitation, may

prove to be lifesaving.

Our experiment was performed on adult cadaveric

specimens. In these specimens, we have demonstrated

that intraosseous needle insertion into cadaveric bone

without a medullary cavity may allow successful access

to the systemic circulation. We suggest that this should

be no less likely in the living subject.

5. Conclusion

This experiment has shown that dye injected into

adult cadaveric bones that should not have medullary

cavities rapidly gained access to the peripheral venous

circulation. We hypothesise that this is because the

increase in the intraosseous pressure by fluid infusion

caused the intramedullary fluid to follow the path of

least resistance, the emissary veins.The calcaneus and radial styloid are both areas at the

distal end of their extremities and so much more

accessible to the physician attempting access in a

crowded resuscitation or prehospital setting (e.g. en-

trapment). Both of them are devoid of overlying vital

structures that might be damaged when obtaining

access.

We do not advocate replacing traditional insertionsites with the sites mentioned above. We simply suggest

that one need not limit oneself to such sites simply

because they have a medullary cavity. We submit that

from a practical standpoint calcaneus and radial styloid

are two sites that lend themselves to easy, secure and

convenient access.

Acknowledgements

We thank the staff of the Dissecting Room of the

Department of Anatomy, Trinity College, Dublin, for

their assistance.

References

[1] Paediatric Advanced Life Support. American Academy of Paedia-

trics, 1997. p. 5�/1.

[2] Lavis M. Pre-hospital adult intraosseous infusion. Pre-Hosp

Immed Care 1999;3:89�/92.

[3] Tocantins L, O’Neill J. Infusions of blood and other fluids into the

general circulation via the bone marrow. Surg Gynaecol Obstet

1941;73:281�/7.

Table 2

Cadaver B

Anatomical site Observation

Right calcaneus Dye immediately observed to extravasate

from veins in the medial aspect of the foot*

Left calcaneus Unsuccessful-intraosseous needle mistakenly

inserted through full width of calcaneus

Right radial

styloid

Dye immediately observed to extravasate

from veins along midshaft of radius*

Left radial

styloid

Unsuccessful-dye leaked back from the

insertion site around the intraosseous needle

* We presume this resulted from accidental damage to vessels from

previous dissection.

G. McCarthy et al. / Resuscitation 56 (2003) 183�/186 185

[4] European Resuscitation Council. Guidelines 2000 for cardiopul-

monary resuscitation and cardiovascular care*/an international

consensus on science. Resuscitation 2000;46:359.

[5] McCarthy G, Buss P. The calcaneus as a site for intraosseous

infusion. J Accid Emerg Med 1998;15:421.

[6] Foex BA. Discovery of the intraosseous route for fluid adminis-

tration. J Accid Emerg Med 2000;17:136�/7.

[7] Atkins, et al. Resuscitation science in paediatrics. Ann Emerg Med

2001;37(4):S45.

[8] Breathnach AS, editor. Frazer’s anatomy of the human skeleton.

6th ed. J & A Churchill Ltd., 1965 [Chapters 1 and 7].

G. McCarthy et al. / Resuscitation 56 (2003) 183�/186186