Diabetes and Fasting Before an Ultrasound in Ajax

If you live with diabetes, the word “fasting” on an appointment sheet probably makes you stop and think. For most people, skipping breakfast before a scan is an inconvenience. For someone who manages blood sugar every day, it raises real questions about insulin, tablets, timing and what happens if a low comes on in the waiting room.

Those questions deserve proper answers, and the most important answers will come from your own diabetes care team, not from a general article. What this guide can do is help you plan: which exams involve fasting, what to ask the people who manage your diabetes, what to tell Rossland Diagnostic Clinic in Ajax when you book, and how to set up the day so that your safety comes first and the scan still gets done.

One point up front, because it matters more than anything else here: do not stop, skip or change your insulin or any diabetes medication to prepare for an ultrasound unless your prescriber has told you to. If you are unsure, ask them. If you cannot reach them in time, call the clinic and talk about rebooking.

Which ultrasounds involve fasting

Not every ultrasound requires an empty stomach. According to our patient preparation guide:

• Abdominal ultrasound requires fasting. For a morning appointment, nothing to eat or drink after 8:00pm the night before. For an afternoon appointment, dry toast, black tea, black coffee or juice before 9:00am, then nothing.
• Abdomen and pelvis together requires not eating for 12 hours before the examination, plus drinking water for a full bladder.
• Pelvic ultrasound alone does not require fasting; you may eat normally, though you will need a full bladder.

Other ultrasound exams, such as musculoskeletal or many vascular scans, have different preparation, which is confirmed when you book. If you are not sure which category your exam falls into, look at the exam name on your requisition or call 905-426-3111.

The reasons for fasting, such as how food and gas affect the images and why the gallbladder needs to stay full, are explained in our abdominal ultrasound preparation guide. This article focuses on what changes when diabetes is part of the picture.

Why fasting needs extra thought with diabetes

In general terms, many diabetes medications are designed to work alongside food. When food is delayed or skipped, the balance can shift. Depending on your treatment, that may raise the chance of low blood sugar, or affect your readings in other ways. How much this matters varies a great deal from person to person: someone managing diabetes with diet alone is in a very different position from someone on insulin.

That is exactly why there is no single instruction that suits everyone, and why the plan should come from the people who know your treatment. The imaging clinic’s role is to provide clear preparation instructions for the scan and to work with you on timing; your prescriber’s role is to tell you how to manage your diabetes around those instructions.

Step 1: Talk to your diabetes care team early

As soon as you know you have a fasting ultrasound booked, or even when the requisition is first handed to you, contact the person who manages your diabetes. That might be your family doctor, nurse practitioner, endocrinologist, diabetes educator or pharmacist.

Bring the specific preparation instructions with you, so they know exactly how long you will be fasting. Questions worth asking:

1. How should I manage my insulin or other diabetes medications during this fast?
2. Should I check my blood sugar more often on the morning of the scan, and at what times?
3. What should I do if my blood sugar is low before or during my appointment?
4. What reading, or what symptoms, would mean I should not go ahead with the fast that day?
5. Is a morning appointment better for me than an afternoon one?
6. Is there anything else about my health that the imaging clinic should know?

Write the answers down and bring them to your Ajax appointment. If the plan is complicated, ask whether it can be written out for you.

Step 2: Tell the clinic when you book

When you call or request an appointment, let the team know that you have diabetes and that your exam involves fasting. You do not need to share more detail than you are comfortable with. It is enough to say something like, “I have diabetes and I take insulin, so I would like to talk about timing.”

Thinking about appointment time

Many people with diabetes prefer an early morning appointment for a fasting scan, because most of the fast happens overnight and the scan is finished before the usual breakfast time. Others, depending on their treatment, may find a different time works better. This is something to decide with your care team, then request when booking. The clinic opens at 9:00am on weekdays and 8:00am on Saturdays, and the team will do their best to find a time that suits your plan, though we cannot promise a specific slot.

If you are having the combined exam

The abdomen and pelvis exam involves the longest fast, 12 hours without eating. If that is what your requisition asks for, it is especially important to discuss it with your care team, and to mention it clearly when you book.

Step 3: Pack for the day

Think of this as a small diabetes kit for the appointment. Your care team may suggest specific items, but people commonly bring:

• Your blood glucose meter or monitor reader, and any supplies you use to check.
• Whatever your care team has advised you to use to treat a low. Keep it in your bag or pocket, not in the car.
• Your diabetes medications, if your plan involves taking them after the scan.
• Food for afterward, so you are not relying on finding something on the drive home.
• Your health card, requisition and a current medication list.
• Diabetes identification, if you normally wear or carry it.

The clinic is at Unit 102, 300 Rossland Road East in Ajax, with free parking right outside and ground-floor access, so your car and your supplies are never far away.

Step 4: On the morning of the scan

Follow the plan from your care team. Check your blood sugar as they advised, and listen to your body.

If you feel low

Your safety comes before the scan. If you have symptoms of low blood sugar, or your meter shows a low reading, treat it the way your care team has told you to, even if that means eating or drinking during your fasting window. Then tell the clinic. Depending on what you needed and when, the exam may still be possible, or it may be better to rebook. A rescheduled ultrasound is a small inconvenience; an untreated low is not.

Common signs of low blood sugar can include shakiness, sweating, a pounding heart, sudden hunger, irritability, confusion or difficulty concentrating. You know your own warning signs best.

If someone is very confused, unable to swallow safely, having a seizure or losing consciousness, call 911 right away. A community imaging clinic is not an emergency department.

Tell the team when you arrive

At check-in, mention that you have diabetes and have been fasting, and let the sonographer know too. If you start to feel unwell during the scan, say so straight away. The exam can be paused.

If your readings are high

Fasting does not always mean lower numbers; some people see higher readings in the morning. If your blood sugar is outside the range your care team considers safe for the day, follow their advice. If you are unsure whether to proceed, call your care team or the clinic before you leave home.

Step 5: After the scan

Once your ultrasound is finished, you can usually return to normal eating straight away, and this is where packing food in advance pays off. Follow your care team’s plan for resuming your usual medication routine, and keep checking as they advised for the rest of the day.

The images from your scan will be reviewed and a report sent to the health-care provider who ordered it. If you have questions about the results, that provider is the person to ask.

Other imaging when you have diabetes

People living with diabetes may be referred for a range of imaging over time, and only some of it involves fasting. A few examples:

• Vascular ultrasound looks at blood flow in arteries and veins. Preparation depends on the vessels being examined and is confirmed when you book, so ask then whether any fasting is involved.
• X-ray usually requires no special preparation.
• Pelvic ultrasound needs a full bladder but not fasting.

Whatever the exam, the same two habits apply: ask your prescriber about your medications, and tell the clinic about your diabetes when you book. Our broader article on medications and imaging preparation covers supplements, creams and other medications that come up with different exams.

A quick planning checklist

Use this as a reminder in the days before your fasting ultrasound:

• I know which exam I am having and how long I need to fast.
• I have spoken with my diabetes care team about my medications and checking plan.
• I have written down what to do if I go low or high.
• I have told the clinic that I have diabetes and requested a suitable time.
• My bag has my meter, supplies for treating a low, food for afterward, health card and requisition.
• I know that if I need to treat a low, I will treat it and tell the clinic.

Planning your scan

Fasting with diabetes is very manageable with a bit of preparation and a clear plan from your care team. Patients across Ajax, Pickering and Whitby come to us for general and vascular ultrasound, and the team is used to working around health needs like these. You can read more on our ultrasound services page, and if you have questions about timing or preparation, call us at 905-426-3111 before your appointment.