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Treatment and the treatment process

Emergency venous access

In sepsis, heavy bleeding or severe dehydration, medicines must be given within minutes. This topic explains how venous access is obtained in an emergency and what it means for someone with leukemia.

Last updated: ~3 min read
A calm, empty emergency bay with a prepared trolley of cannulas, fluid bags and an ultrasound machine.
Figure 1.A ready emergency bay saves time.

01Short answer

Emergency venous access is needed in life-threatening situations, such as neutropenic sepsis, heavy bleeding or shock, to give antibiotics, fluids, blood and medicines quickly. The fastest route is usually a peripheral cannula in the arm, often two. If veins are hard to find, ultrasound helps. If that also fails, fluids can be given into the bone with a special device (intraosseous access), because the bone marrow connects to the circulation. In people with a central line, the existing line is often used, bearing in mind it could be a source of infection. Once the person is stable, a decision is made about longer-term access.

02Simple explanation

Why the hurry? In sepsis every hour counts: the sooner antibiotics start, the better the outcome.

The simplest route is one or two cannulas in the arm. This takes a few minutes.

If veins are difficult, ultrasound shows the vein on screen so the doctor can place the cannula precisely.

The bone route. Rarely, when no vein can be found, a special needle gives access into a bone (such as the shin bone). It is a temporary, safe method.

03Scientific explanation

Neutropenic sepsis: according to CRUK and the NCI, with fever and low neutrophils after chemotherapy, intravenous antibiotics should start as soon as possible, ideally within an hour. Venous access is the first step.

Intraosseous access: per Resuscitation Council UK guidance, if venous access cannot be gained quickly, intraosseous access is an effective alternative for drugs and fluids. With very low platelets, this decision is made carefully.

An existing line: according to the CDC, if a line is suspected as the source of infection, paired blood cultures are taken from the line and from a peripheral vein; sometimes the line has to be removed.

04What happens in the body?

What you can do

On arrival, give your diagnosis and the date of your last chemotherapy, and say whether you have a line. Carry your line details (type, date placed). Mention any past difficulty with veins.

Fluids and blood

In an emergency, intravenous fluids help support blood pressure, and blood and platelets are transfused for severe anemia or bleeding. Doctors adjust fluid amounts to the state of the heart and kidneys.

A clear fluid bag on a stand with a bright drop forming in the drip chamber.
Figure 3.Intravenous fluids support blood pressure.

What happens next?

Once stable, temporary cannulas or intraosseous access are removed. If treatment continues, a more suitable central or long-term line is planned.

A small intraosseous access device and sealed needle set on a sterile tray.
Figure 2.Intraosseous access: a temporary route when no vein is found.

05Steps of emergency access

From simple to complex.

Arm vein — One or two cannulas.1Arm veinOne or two cannulas.
Ultrasound — For difficult veins.2UltrasoundFor difficult veins.
Bone route — When no vein is found.3Bone routeWhen no vein is found.
Stabilise — Then plan lasting access.4StabiliseThen plan lasting access.
AntibioticsAs soon as possible.
FluidsSupport blood pressure.
BloodTransfusion if needed.

06Emergency access methods

MethodWhen?Note
Peripheral cannulaFirst choiceFast, usually minutes
Ultrasound-guided cannulaVeins hard to findImproves success
Existing central lineIf one is in placeMay be a source of infection
Intraosseous accessNo vein foundTemporary; replaced within hours
New central lineLong or special treatmentPlanned after stabilisation

* The emergency team chooses according to the situation.

07Key terms

Sepsis
A dangerous whole-body reaction to infection.
Cannula
A short plastic tube placed in a vein.
Intraosseous access
Giving drugs and fluids by needle into the bone marrow.
Blood culture
A test that looks for germs in the blood.
Shock
Not enough blood reaching the organs.

08Key points

  • Speed matters in an emergency.
  • The first route is an arm vein.
  • Ultrasound helps with difficult veins.
  • The bone route is a temporary alternative.
  • Say straight away that you have a line.
  • A plan is made once you are stable.

09Frequently asked questions

Why did they put a cannula in my arm when I have a line?

The line may be a source of infection, or an extra route was needed. This is routine.

Is a needle into the bone dangerous?

It is widely used in emergency medicine; it stays in briefly and is removed soon.

Is access risky with low platelets?

Doctors take this into account, choosing a safer site and giving platelets if needed.

How can I prepare at home?

Keep your team’s number, medicines list, line details and discharge summary in one folder.

10Questions for your doctor

Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.

  1. Why did they put a cannula in my arm when I have a line?

  2. Is a needle into the bone dangerous?

  3. Is access risky with low platelets?

  4. How can I prepare at home?

My questions

12Sources

  1. NHS. Sepsis
  2. NHS. Sepsis
  3. National Cancer Institute (NCI). Infection and Neutropenia during Cancer Treatment
  4. MedlinePlus. Intravenous
  5. Resuscitation Council UK. Adult advanced life support guidelines (2025)
  6. CDC. Guidelines for the Prevention of Intravascular Catheter-Related Infections
  7. National Cancer Institute (NCI). Immunotherapy for Cancer
  8. New England Journal of Medicine, 2016. Inotuzumab Ozogamicin versus Standard Therapy for Acute Lymphoblastic Leukemia
  9. New England Journal of Medicine, 2017. Blinatumomab versus Chemotherapy for Advanced Acute Lymphoblastic Leukemia
  10. New England Journal of Medicine, 2018. Tisagenlecleucel in Children and Young Adults with B-Cell Lymphoblastic Leukemia
Medical disclaimerThis information is for educational purposes only and does not replace medical advice.
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