On-call rarely goes badly because you didn’t know a rare diagnosis.

It usually goes badly because of:

poor prioritisation
delayed escalation
missing basics
fatigue
small system errors

The same mistakes happen again and again.

Especially when you’re tired at 3am.

This guide isn’t to criticise.

It’s to help you recognise traps early — so you don’t fall into them.

Most of these mistakes are completely preventable.

🔴 Mistake 1 — Starting with paperwork

Very common at the start of shift.

You sit down to:

discharge summaries
TTOs
rewriting charts

Then suddenly:

NEWS 8
hypotension
sepsis

Now you’re behind and stressed.

Better approach

Always:
👉 sick patients first
👉 admin last

Night shift = safety work, not paperwork perfection.

Admin can wait. Deterioration can’t.

🔴 Mistake 2 — Walking to every bleep without triaging

Junior reflex:
Bleep → walk immediately

Result:

wasted time
random running
poor prioritisation
exhaustion

Better approach

Always ask:

obs?
NEWS?
what exactly is wrong?
stable or not?

Triage first. Move second.

A 20-second phone call saves 20 minutes of walking.

🔴 Mistake 3 — Jumping to diagnosis before A–E

Classic error.

You think:
“Probably infection”

But you haven’t checked:

airway
sats
BP
glucose

Meanwhile the patient is hypoxic or hypotensive.

Better approach

Always:
👉 A–E first
👉 treat abnormalities
👉 then think diagnosis

Stabilise first. Think later.

🔴 Mistake 4 — Delaying simple treatments

Waiting for:

bloods
scans
seniors

Before giving:

oxygen
fluids
antibiotics
glucose

These delays harm patients.

Better approach

If something is abnormal:
Fix it immediately.

Basic treatments save lives more than tests.

🔴 Mistake 5 — Not escalating early enough

Very common mindset:

“I’ll try one more thing first…”

Then:

patient crashes
you panic
senior arrives too late

Better approach

Escalate when:

unstable
not improving
you’re unsure
gut feeling says “not right”

Early calls are respected.

Late calls are risky.

🔴 Mistake 6 — Ignoring nurses’ concerns

Dangerous.

If an experienced nurse says:
“I’m worried”

And you think:
“Obs look okay”

You may miss early deterioration.

Nurses often spot problems first.

Better approach

Always take concerns seriously.

Go review.

Better one unnecessary review than one missed arrest.

🔴 Mistake 7 — Not writing things down

At 3am your brain is unreliable.

If you don’t write a job:
You will forget it.

Guaranteed.

Better approach

One master list.

Write every task immediately.

Paper > memory when tired.

🔴 Mistake 8 — Trying to multitask everything

Running between:

cannula here
review there
half-finished jobs everywhere

Result:

incomplete work
mistakes
mental overload

Better approach

Finish one job properly before moving (unless emergency).

Batch by ward.

Less walking. Less chaos. Safer.

🔴 Mistake 9 — Poor documentation

Notes like:
“Reviewed. Stable.”

Mean nothing.

Morning team doesn’t know what you did.

You’re not protected medico-legally.

Better approach

Always document:

time
A–E
actions
plan
escalation

Clear, short, structured.

Not essays.

🔴 Mistake 10 — Skipping breaks and food

Very common and very harmful.

By 4am you’re:

dehydrated
hungry
cognitively slower

This is when prescribing errors happen.

Better approach

Small breaks.
Drink water.
Eat snacks.

Fatigue is a patient safety issue, not a luxury issue.

🔴 Mistake 11 — Treating everything as urgent

If everything is urgent → nothing is.

You end up:

exhausted
inefficient
missing the truly sick patient

Better approach

Traffic light thinking:

🔴 sick
🟠 urgent
🟢 routine

Only RED gets immediate action.

Everything else waits.

🔴 Mistake 12 — Trying to “clear all jobs”

You will never finish every task on nights.

Trying to do so leads to:

rushing
poor decisions
burnout

Better approach

Shift goal:
👉 keep patients safe

Not:
👉 complete everything

Safety first. Completion second.

The senior mindset (what changes with experience)

Calm registrars don’t:

run faster
know every answer

They simply:

prioritise better
escalate earlier
stick to A–E
ignore low-value noise
protect their energy

It’s systems, not intelligence.

You can learn this from day one.

A simple self-check during your shift

Every hour ask:

Am I seeing sick patients first?
Am I doing admin too early?
Do I need to escalate anyone?
Am I tired/hungry/dehydrated?

Small resets prevent big mistakes.

Take-home concept

Most on-call problems aren’t medical knowledge problems.

They’re system problems and human factors.

If you avoid these common mistakes, you’ll already be safer than most juniors.

Good on-call practice isn’t about being brilliant.

It’s about avoiding predictable errors.

Safe > clever.

Always.