A surgical error becomes a malpractice claim in Illinois when a surgeon, anesthesia provider, nurse or hospital falls below the accepted standard of care before, during or after an operation and that failure causes the patient harm. Examples include operating on the wrong site, leaving an object inside the patient, anesthesia mistakes, performing a procedure without proper informed consent, and failing to respond to complications after surgery. A known complication is not automatically negligence. Most claims against physicians, dentists, registered nurses and hospitals must be filed within two years of when the patient knew or should have known of the injury, and no more than four years after the act or omission (735 ILCS 5/13-212), with exceptions. Call Stavros Law Offices at (847) 520-4810 for a free consultation.

General information, not legal advice. Last reviewed: October 2026.

This page is part of our medical malpractice resource. It describes common kinds of surgical errors and what a patient generally has to prove.

Not Every Bad Surgical Outcome Is Malpractice

All surgery carries risk. Bleeding, infection, scarring and unexpected reactions can happen even when the surgical team does everything correctly, and a patient who agreed to a procedure after being told about its risks has not necessarily been wronged when one of them occurs. The question in a malpractice claim is whether the care fell below what a reasonably careful provider would have done in the same circumstances, and whether that departure caused harm. A qualified health professional has to answer those questions after reviewing the records.

Common Types of Surgical Errors

Wrong-Site, Wrong-Patient or Wrong-Procedure Surgery

These errors involve operating on the wrong side of the body, the wrong body part, the wrong patient, or performing a different procedure than the one planned. Hospitals and surgery centers generally use checks such as confirming the patient's identity, reviewing the consent form, marking the site and pausing for a team verification before the first incision. When those checks are skipped or fail, a claim may be worth reviewing.

Retained Surgical Objects

Sponges, towels, clamps or other instruments or fragments can be left inside a patient after an operation. The result may be pain, infection, a bowel or organ injury, or a second operation to remove the object. Operating rooms commonly use counts of sponges and instruments to prevent this, so the records of those counts, and any imaging that found the object, are important evidence.

Anesthesia Errors

Anesthesia problems can include incorrect dosing, failure to review the patient's history, allergies or medications, inadequate monitoring of breathing, oxygen levels or blood pressure, airway complications, and failure to respond quickly to a change in the patient's condition. Positioning injuries to nerves or eyes during a long procedure are sometimes reviewed as well. The anesthesia record, which tracks the patient's vital signs and medications minute by minute, is often central.

Errors in Technique

A surgeon may injure a nearby organ, blood vessel, duct or nerve, use an inappropriate approach, or fail to recognize and repair an injury during the operation. Because some injuries are known risks, the review focuses on whether a careful surgeon would have avoided the injury or caught it in time.

Informed Consent

Patients are generally entitled to be told about a proposed procedure in terms they can understand, including its purpose, its material risks and the reasonable alternatives, so they can decide whether to go forward. A claim may arise if important risks or alternatives were not disclosed and the patient was harmed by a risk that should have been explained. A signed consent form is not the end of the question. What was actually discussed with the patient can matter, as can whether the risk that occurred was one a reasonable provider would have disclosed.

Post-Operative Care

Problems also happen after the operation ends. Claims can involve failure to monitor a patient in recovery, failure to recognize and treat infection, internal bleeding or a leak, ignoring worsening pain, fever or abnormal labs, discharging a patient too early, giving wrong medication instructions, or delaying a return to surgery when one was needed. Nurses, the surgeon and the hospital may each have roles to review.

What Has to Be Proved

A surgical malpractice claim generally requires showing each of the following:

• A provider-patient relationship, meaning the defendant owed the patient a duty of care.
• A departure from the standard of care, meaning what the provider did or failed to do was not what a reasonably careful provider would have done.
• Causation, meaning the departure, rather than the underlying condition or an unavoidable risk, caused the injury.
• Damages, such as additional surgery, medical expenses, lost income, pain and suffering, or lasting impairment.

Surgical cases usually depend on the records: the consent forms, pre-operative evaluation, operative report, nursing notes, anesthesia record, instrument and sponge counts, imaging, recovery-room notes and discharge papers. Qualified health professionals review those records and give opinions about the standard of care and causation.

In some situations, such as an object left inside a patient, a plaintiff may rely on a doctrine called res ipsa loquitur, which in general terms allows an inference of negligence from the nature of the event. Whether it applies is a legal question that depends on the facts, and Illinois law adds a certification requirement when it is used (735 ILCS 5/2-622). It does not remove the need to review the case.

Who May Be Responsible

A surgical injury may involve more than one person or entity: the operating surgeon, an assistant, an anesthesiologist or nurse anesthetist, operating room and recovery nurses, and the hospital or surgery center. Whether each is legally responsible depends on that person's role and on how they are connected to the facility. Illinois requires a separate report from a qualified health professional for each defendant named in a malpractice complaint (735 ILCS 5/2-622).

The Section 2-622 Report and Your Deadline

A malpractice complaint in Illinois must be filed with an affidavit and a written report from a qualified health professional who has reviewed the records and found a reasonable and meritorious cause for filing (735 ILCS 5/2-622). The report is a procedural requirement, not a promise that a case will succeed. See our page on how a medical malpractice lawsuit works.

The general deadline is two years from when the patient knew or should have known of the injury, with a four-year outer limit from the act or omission, and exceptions for minors and legal disability (735 ILCS 5/13-212). Surgical errors are sometimes found well after the operation, for example when an object shows up on a later scan, so the dates should be reviewed early. See our page on medical malpractice deadlines in Illinois.

What to Do If You Think Something Went Wrong

• Get appropriate medical care for any ongoing problem.
• Write down dates, names and what you were told while it is fresh.
• Keep discharge papers, bills, medication lists and any consent forms you were given.
• Request your records in writing from each facility and provider.
• Do not sign a release or discuss the matter with an insurer without understanding what it means.

Related Medical Malpractice Topics

• Misdiagnosis and delayed diagnosis in Illinois
• Birth injury claims in Illinois
• Medical malpractice overview

Frequently Asked Questions

Is a surgical complication always malpractice?

No. Some complications can occur even when surgery is performed correctly. A claim generally requires that care fell below the accepted standard and that the failure caused harm, which a qualified health professional must review.

What can I do if a sponge or instrument was left inside me?

Get medical care first. Then keep your records and imaging, write down the dates, and talk with an attorney about the facts and your deadline. A retained object is the type of event a qualified reviewer can evaluate using the operative and counting records.

Does signing a consent form prevent a claim?

Not necessarily. A signed form shows that a conversation was documented, but it does not by itself answer whether the risks were explained or whether the harm came from a risk that was disclosed, or from negligence.

Who can be named in a surgical malpractice case?

Possible defendants include surgeons, anesthesia providers, nurses and hospitals or surgery centers, depending on their roles. Illinois requires a separate written report for each defendant (735 ILCS 5/2-622).

Does it cost anything to talk with Stavros Law Offices about my case?

The initial consultation is free. Call (847) 520-4810 and bring your dates and any records you have.

Talk to Our Team

Stavros Law Offices is one team handling criminal defense and DUI, personal injury and civil litigation. Call (847) 520-4810 or request a free consultation online. Our bilingual staff can assist. Se habla español.

Stavros Law Offices
433 N. Milwaukee Ave, Wheeling, IL 60090
(847) 520-4810
Monday–Friday 9–5; closed Saturday
Serving clients in Cook, Lake, McHenry, Kane and DuPage Counties.

General information, not legal advice; no attorney-client relationship until engaged; past results do not guarantee a similar outcome. Laws and deadlines change and every case is different. Last reviewed: October 2026.