Intraosseous (IO) Access

Objectives

To guide military medical personnel in gaining intraosseous (IO) access to the circulatory system.  

Scope 

This guideline describes the procedure to gain IO access to the circulatory system. It is intended to support military clinicians in all situations where IO access may be required from forward pre-hospital emergency care setting through to deployed hospital care.

This guideline explains how to conduct IO access using the two IO access products used by the Defence Medical Services: 

• EZ-IO - the Arrow™ EZ-IO™ System 

• FAST IO - the FAST1™ IO System for use at sternal IO sites only.  

Audience 

This guideline is intended for use by military personnel who have already received training in the performance of IO access as part of their job role, including registered healthcare professionals and military medical personnel who are not professionally registered but have been appropriately trained in the use of IO devices. 

Background

IO access is a widely used technique in emergency situations where access to a patient’s circulatory system is required but intravenous (IV) access is difficult or cannot be achieved quickly enough.  IO access is recommended in these situations by both the UK Resuscitation Council and European Resuscitation Council. IO access has a low complication rate (<0.1%) when used in prehospital patients. 

Indications

Failure to gain IV access in a patient (adult or paediatric) requiring emergency treatment.  

Examples of these types of patients include:  

• cardiac arrest (medical or traumatic)
• shocked patients (e.g. haemorrhage or sepsis)
• severe trauma
• seizures 
• hypothermia 
• severe burns 

Preparation

Patient preparation

• Ensure the patient is appropriately positioned: e.g. supine on a stretcher or semi-reclining 

• Ensure the area you wish to site the IO device in is exposed, and clean. 

• Insertion of an IO device and infusion through it will be painful in awake patients. If possible, give fast-acting oral, IM or IN analgesia prior to IO insertion. 

Insertion site selection

In adults: 

• the proximal humerus is the preferred site for IO access due to proximity to the central venous circulation. 

• the proximal tibia can also be used but should be avoided if there is a suspicion of pelvic/intra-abdominal bleeding or vessel disruption. 

• the sternum can also be used (FAST™ only). 

In children, refer to ‘Paediatric Considerations’ section below.

Do not attempt to insert an IO device if there is:

• suspected or confirmed fracture at the insertion site
• fracture suspected proximal to the insertion site
• a tourniquet in place proximal to the insertion site
• evidence of infection overlying the insertion site 

Landmark Identification

Proximal humerus: 

• Adduct and internally rotate the arm 

• Place the palm of your hand over the humeral head anteriorly (it should feel like a ball and this is the general area where the IO needle will be inserted) 

• Use your thumbs to palpate the humeral head and then move distally down the humerus: you will feel the ‘ball’ (humeral head) fall away from your thumbs as you move over the surgical neck of the humerus (where the bone shaft of the humerus meets the ball-like humeral head). 

• The insertion point is 1-2cm proximal to the surgical neck, which should correspond to the most prominent aspect of the greater tubercle. 

• Typically use the yellow needle for adult patients at this site. 

Figure 1: Proximal Humerus Landmarks in Adults 

Proximal tibia: 

• Extend the leg 

• Find the tibial tuberosity 

• Insertion site is the wide flat surface of bone approx.. 2cm medial to the tibial tuberosity 

• Typically use the blue needle for adult patients at this site.  

Figure 2: Proximal Tibia IO Insertion Site 

Equipment preparation

Two IO access systems are used by the DMS: 

• EZ-IO - the Teleflex®  Arrow™ EZ-IO™ System 

• FAST IO - the Teleflex® FAST1™ IO System for use at sternal IO sites only. 

Both systems have different components. 

The EZ-IO™ System comprises: 

• 1x EZ-IO™ Power Driver. Check indicator light shows green by testing prior to use. 
• 3x IO needles comprising: stylet-catheter assembly, with safety cap in sterile packaging in 3 sizes: 
  • Yellow: 45mm needle length, usually for adult use 
  • Blue: 25mm needle length, for adult or paediatric use 
  • Pink: 15mm needle length, for paediatric use - not normally carried in DMS modules
• 1x EZ-Connect™ extension set: this must be primed with 0.9% saline or local anaesthetic (e.g. 2% lidocaine) depending on operator experience. 
• 1x EZ-Stabiliser™ Dressing 
• 1x Sharps disposal block 

Figure 3: EZ-IO™ Power Driver & Needle Sets 

Needle-set selection

The EZ-IO™ needle-sets can but used on adults and children. The shortest, pink needle (15mm) is not normally available in the deployed setting.

The choice of needle will depend on the site chosen and patient body shape/weight. In general, for adult patients: 

• yellow needle-set = proximal humerus 

• blue needle-set = proximal tibia 

All needle-sets are marked with concentric black bands every 5mm. Then the needle tip is in contact with bone, the 5mm mark closest to the needle hub must be visible above the skin. This ensures the needle will be long enough to penetrate the bone cortex when the operator activates the driver, and ensures the tip will be in medullary bone.

If no concentric black band is visible when the needle tip is in contact with the bone, stop the procedure and exchange for a longer needle.

Figure 4: Incorrect (L) vs Correct (R) Needle Length with 5mm marker band visible above the skin when needle-tip is in contact with bone. 

The FAST1™ IO System is designed for sternal IO access only and comprises: 

1. FAST IO insertion device with needle cover 

1. 1x Target patch 

1. 1x Protective dome dressing 

1. 1x red sharps plug 

Figure 5: FAST1™ IO System components (source: www.teleflex.com)  

Additional equipment

If available, you should supplement your IO equipment with: 

• Cleaning swabs/wipes 

• 3-way tap (to connect to the extension tube from the device)

• 50ml syringe (to connect to the 3-way tap) to help rapidly administer larger fluid/medication volumes 

• Sharps bin 

• Clinical waste bag 

 You should also prepare: 

• Any medications you intend to deliver through the IO device 

• A flush syringe to follow any medications you administer (10ml of 0.9% sodium chloride) 

Procedure 

EZ-IO™ System

Conduct actions listed in ‘Equipment Preparation’ above including priming the extension set.

Select and identify site as outlined in ‘Landmark Identification’ above: consider injury pattern, team positions, patient age and weight.

Proximal humerus: aim needle-set at a 45-degree angle as if aiming for opposite hip.

Proximal tibia/distal tibia/distal femur: aim needle-set at 90-degree angle to the bone.

Clean the insertion site, then while allowing to dry load the needle-set onto driver; maintain aseptic technique and do not touch metal parts.

Push needle tip through skin until needle tip rests on bone. Confirm at least one black line is visible above the skin prior to drilling.

Squeeze trigger and apply gentle, steady pressure, keeping angle consistent. Immediately release trigger when you feel a ‘give’ or loss of resistance.

Unscrew introducer needle and dispose of safely in sharps bin/sharps block. 

Apply stabiliser dressing. 

Connect primed extension set (with 3-way tap if available) to the needle hub (screw-fit).

Ensure the white clip on the extension set is open. 

Attempt to aspirate a small amount of bone marrow to confirm placement. Bone marrow may not always be aspirated.

Flush rapidly with 5-10ml 0.9% saline. Be aware that flushing the correctly sited IO device is likely to cause significant discomfort to the conscious patient.

Once flushed, drugs and fluids can be administered via the 3-way tap or by directly connecting to the bung on the end of the extension set – do not connect syringes directly to the IO needle hub as this risks dislodging the device.

Immobilise or secure the limb used for IO access to prevent displacement.  

FAST IO System 

Conduct actions listed in ‘Equipment Preparation’.

Identify the sternal notch and manubrium: the manubrium is the site for insertion. 

Clean the area and while allowing to dry remove protector dome and tab 1 from the adhesive side of the target patch.

Keeping the concave part of the target patch in-line with the sternal notch, place target patch on chest. The hole on the target patch should overly the manubrium. Peel off tab 2 and ensure the target patch is stuck down to the chest securely. 

Place the needles of the FAST IO device into the target zone of the target patch, ensuring needles are at 90-degrees to the patient’s chest. Using a two-handed grip, press down on the  device with firm and increasing pressure until the device releases.  

Remove the device and put the needles into the red sharps plug: the device is now safe and is not reusable. Dispose of in sharps bin. 

Remove the blue cap from the end of the connector tubing on the target patch and connect to the IO tube.  Remove the white cap from the base of the connector tubing on the target patch and attempt to aspirate a small amount of bone marrow to confirm placement. 

Flush rapidly with 5-10ml 0.9% saline then connect to a giving set or 3-way tap if using. Do not leave the end of the connector tubing uncovered.

Secure the protector dome over the target patch.

Post-Procedure Care

Infusions by IO need pressure to achieve sufficient flow rates. This can be achieved by a pressure bag, gentle manual pressure on the infusion bag, or by using a syringe and 3-way tap system (see ‘infusions of blood or crystalloid via IO access systems’ below). 

In conscious patients, ensure pain due to IO infusion is treated adequately. 

Aim to convert IO access to peripheral IV access as soon as possible if resources allow.  

During infusion/drug administration, observe for signs of local swelling that may indicate device displacement, and remove/stop if this occurs. Complications are rare but may can include: 

• local swelling/oedema: e.g. if ‘though and through’ needle penetration has occurred (more likely in children) or the IO needle becomes displaced from the medullary bone. 

• osteomyelitis, osteonecrosis, compartment syndrome (rare, occurring <0.1% of cases in one study of 5387 patients) 

EZ-IO™ needles can remain in-situ for up to 48hrs but should be removed as soon as more secure peripheral or central IV access has been achieved. 

The FAST sternal IO should be removed as soon as soon as more secure peripheral or central IV access has been achieved. 

The site of IO access must be noted in clinical documentation and clearly communicated to subsequent treatment teams.

Paediatric Considerations

Peripheral IV access can be particularly challenging in unwell paediatric patients. IO access is a recommended technique for paediatric patients of all ages requiring emergency medications where IV access has not been achieved quickly or is not possible. 

The FAST IO device is only recommended for use in children aged >12 years. The EZ-IO device may be used in children of any age but there are some differences regarding IO site selection, landmark identification and needle-set selection.  

Insertion site selection in children 

In children more insertion sites can be used: 

• the proximal tibia is most commonly used (easily identifiable, away from airway/chest in resuscitation) 

• distal tibia 

• distal femur 

• proximal humerus: may be harder to identify in children. Use if pelvic/lower limb trauma prevents use of other sites. 

Landmark identification in children

 Proximal humerus - as for adults. 

 Proximal tibia:

• Newborns, infants and small children: 1cm below and 1cm medial to the tibial tuberosity on the anteromedial surface of the tibia. Very young children may not have yet developed a palpable tibial tuberosity: in such cases the insertion point is 2-3cm distal to and 1cm medial to the lower end of the patella.
• Older children and adolescents: 2-3cm below and medial to the tibial tuberosity on the anteromedial surface of the tibia.

Distal tibia (children <16yrs only) 

• Newborns, infants, small children: 1-2cm proximal to the most prominent aspect of the medial malleolus
• Older children: 3cm proximal to the most prominent part of the medial malleolus. 

Distal femur (children <6yrs only)

• The general area is the centre-medial aspect of the distal femur (avoid the patellar tendon in the midline).
• Hold the leg straight, knee immobilised.
• Site should be 1-2cm above the patella and 1-2cm medial from the midline.  

Needle-set selection in children

All EZ-IO needle-sets can be used on children. Needle-set selection using the concentric black bands is the same for children and adults. 

• yellow EZ-IO™ needle-set = larger child >40kg / adolescent proximal humerus 

• blue EZ-IO™ needle-set = all sites depending on age/weight. 

The pink EZ-IO™ needle-set is particularly intended for newborns or infants. This needle is not carried within any DMS modules and is therefore unlikely to be available on deployed operations. The manufacturer's advice is that the blue needle can be safely used on any patient >3kg. 

Selection of needle by colour based on age and site is only a guide: if no concentric black band is visible when the needle tip is in contact with the bone, stop the procedure and exchange for a longer needle.

The FAST1™ IO system is only recommended for use on children aged >12yrs. 

Prolonged Casualty Care

IO needles should be removed as soon as more secure IV access can be achieved. It is advisable to immobilise/secure limbs used for IO access to reduce the risk of needle displacement during casualty movement etc and for conscious patients this immobilisation should not be continued longer than necessary: it will be uncomfortable and will make onward movement/self care etc more difficult.  

Peripheral IV access in shocked patients should become easier as treatment progresses. 

Although the manufacturer recommends EZ-IO™ removal within 48 hours of insertion, in the prolonged casualty care setting it would be acceptable to continue to use the IO needle if this was the only point of circulatory access available for a patient who required time-critical medications. In this situation, the likely harm from not giving further treatments would probably be greater than the risks of complications from the IO needle remaining in situ for longer than 48 hours.