Below is a practical guide to how these failures happen, what injuries they can cause, what to do if you suspect a malfunction, and how catastrophic-injury product cases are investigated.

Why pump and CGM failures can turn dangerous fast

Diabetes devices sit at the intersection of hardware, software, and human physiology. A single failure point can trigger a chain reaction:

• A CGM reads “low” when glucose is not low, prompting unnecessary treatment or insulin reduction.
• A pump fails to deliver basal or bolus insulin, leading to uncontrolled hyperglycemia.
• An AID system makes dosing decisions based on faulty inputs or interrupted communication.
• Critical alarms do not sound, or the device shuts down unexpectedly.

Regulators have issued high-level safety communications and recalls involving both CGMs and pumps, including alerts tied to inaccurate readings and insulin delivery interruptions.

Over-delivery: when too much insulin is delivered

Over-delivery can cause rapid, severe hypoglycemia. In the worst cases, low blood sugar leads to seizure, loss of consciousness, brain injury, or death.

Common mechanisms that can contribute to over-delivery include:

• Software or dosing logic errors (especially where apps or automated features are involved)
• Unintended commands from a connected device
• Device malfunction that results in unplanned insulin delivery
• False low or false high CGM readings that push the system toward unsafe dosing decisions

CGM accuracy matters because users and systems make treatment decisions based on the number on the screen. The FDA has warned about specific CGM sensors that may provide incorrect low glucose readings, which can lead to dangerous decisions.

Under-delivery: when insulin is delayed, interrupted, or stops

Under-delivery is a common pathway to diabetic ketoacidosis (DKA), a medical emergency that can escalate quickly and become fatal without prompt treatment.

Typical under-delivery scenarios include:

• Pump shutdown, unexpected power loss, or battery drain tied to software issues
• Occlusions, infusion set failures, or cannula problems that block delivery
• Mechanical defects that impair pump function
• Alarm failures that prevent the user from realizing insulin has stopped

Recent FDA communications have described pump corrections and recalls involving risks that the device may malfunction and stop insulin delivery, including issues where alarms may not function as intended.

When CGM problems create pump problems

Many modern systems are integrated. That means a CGM problem can become a pump problem:

• Inaccurate readings can drive inappropriate dose changes
• Signal dropouts can lead to missed automation or delayed responses
• App failures can interfere with monitoring, alerts, or system behavior

This is why FDA and manufacturer alerts increasingly focus on the “system,” not just a single component.

Severe outcomes we see in catastrophic injury cases

When a diabetes device fails, the resulting harm is often major. Severe outcomes can include:

• Hypoglycemic seizures, coma, anoxic brain injury
• DKA with ICU admission, organ injury, or death
• Falls, vehicle crashes, or workplace incidents triggered by sudden hypo or hyperglycemia
• Long-term cognitive impacts after severe hypoglycemia events

What to do if you suspect a pump or CGM failure

If you believe a device malfunction contributed to an emergency, the steps you take in the first days matter for both safety and evidence.

1. Get medical care immediately.
2. If someone is symptomatic, treat it as an emergency. Follow your care plan and seek urgent care or call 911 when appropriate.
3. Preserve the device and supplies.
4. Do not throw away the pump, sensor, pods, infusion set, inserter, packaging, or chargers. Keep everything in a safe place.
5. Save data now.
6. Download or screenshot pump history, CGM graphs, alerts, app logs, and any “event” summaries. Time-stamped data often becomes critical.
7. Check for recalls and safety notices.
8. The FDA maintains a searchable recall database, and manufacturers often publish “corrections” and replacement programs.
9. Write down a timeline.
10. Document symptoms, readings, alarms (or lack of alarms), actions taken, and when care was sought.

How product liability investigations usually work in device failure cases

In catastrophic injury and wrongful death matters involving pumps or CGMs, investigations often focus on:

• Device design and known failure modes
• Software updates, app behavior, and connectivity logs
• Manufacturer warnings, instructions, and training materials
• Recall history and internal corrective actions
• Whether safer alternative designs or safeguards were feasible

Depending on the facts, claims may involve product defect (design or manufacturing), failure to warn, negligence, or breach of warranty.

Talk to a product liability attorney about an insulin pump or CGM injury

If you or a loved one suffered severe hypoglycemia, DKA, hospitalization, neurologic injury, or a wrongful death where an insulin pump, CGM, pod system, or connected app may have failed, you do not have to sort it out alone.

McEldrew Purtell investigates catastrophic injury and wrongful death cases nationwide, including complex product liability matters involving medical devices and digital health systems. Contact us for a free, confidential case review.