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Image: “The anesthetic area of an operating room.” by Coronation Dental Specialty Group – Own work. License: CC BY-SA 3.0

Classification of Emergencies in the Operation Room

An anesthesia provider requires a combination of skills, such as anatomical knowledge of the airway, knowledge of the varied pharmacologic agents used, along with their effects and interactions, drug titrations, ability to manage stress and provide relief to an anxious, often critically ill patient. There can be several anesthesia-related emergencies in the operating room and they can be classified as follows:

Drug induced

Patient related

  • Difficult airway
  • Aspiration
  • Laryngospasm
  • Massive hemorrhage
  • Brain swelling – increased intracranial pressure
  • Ischemic cardiac disease

Iatrogenic (doctor induced)

  • Incorrect drug administration
  • Incorrect dose administration
  • Incorrect site of surgery
  • Incorrect surgery
  • Hemorrhage

Drug-Induced Emergencies

Anesthesia agents (e.g. muscle relaxants) and medications (e.g. antibiotics) can lead to anaphylaxis, malignant hyperthermia and hyperkalemic cardiac arrest in the operation room.

It is imperative for the anesthesia provider to promptly identify the condition and start treatment. For example, if muscle rigidity is noticed during intubation accompanied by tachycardia, cyanosis, and hyperthermia, then malignant hyperthermia should be suspected and immediate management instituted with hyperventilation, active cooling, dantrolene, etc.

Anaphylaxis to a drug can manifest as skin rash and bronchospasm. It should be managed with the administration of subcutaneous epinephrine, corticosteroids, and adequate oxygenation while monitoring the airway.

drug induced emergencies in OR

Patient Related Emergencies

Difficult airway

A difficult airway should be anticipated in patients who are obese, have a short, broad neck, medical co-morbidities or upper airway tumors or maxillofacial fractures/deformities.

In all such cases, a preoperative plan for alternative airway in an emergency like tracheal intubation/cricothyrotomy/tracheotomy should be in place. Flexible laryngoscopes, airway bougies, and equipment for emergency airway intubation should be kept ready.


A patient without adequately functioning airway reflexes due to a recent meal (inadequate starvation period), delayed gastric emptying (bowel obstruction, pregnancy, pain or opiates) can regurgitate gastric contents into the airway and lungs during induction of anesthesia.

It is imperative for the anesthesia provider to place a nasogastric tube to remove gastric contents prior to induction, apply adequate cricoid pressure during intubation and extubation to prevent aspiration.


Patients, especially children, are very sensitive to airway manipulation which can lead to laryngospasm. Other causes of laryngospasm are blood, or secretions on the vocal cords, surgical stimulation or failure to provide an anesthetic agent.

Massive hemorrhage

This can occur unexpectedly during a surgical procedure if a blood vessel is accidentally severed or in cases of trauma wherein the patient is brought to the operating room with blunt trauma to the abdomen.

In all cases of hemorrhage, whether anticipated or unanticipated, anesthesia providers should anticipate and request for crossmatched blood and blood products, as well as colloidal fluids, and ensure that the correct product is used in the patient to prevent anaphylaxis.

Pulmonary edema

Pulmonary edema can develop if excessive fluids/blood products are administered to a hemorrhaging patient or if the patient has other medical co-morbidities at the onset of surgery.

Anesthesia providers should monitor the amount of fluids being administered, as well as the airway secretions (frothy pink secretions in pulmonary edema) being suctioned through the endotracheal tube.

Brain swelling – increased intracranial pressure

Although the exact etiology of cerebral edema during surgery is not known, it is encountered commonly during neurosurgical procedures. The etiology is believed to be multifactorial with subarachnoid hemorrhage or intraventricular hemorrhage leading to acute intracranial hyperemia and cerebral edema.

The anesthesia provider should anticipate this event in all surgeries, but especially during neurosurgical/head trauma surgeries and plan for the management of such events.

Ischemic cardiac disease

The stress of a surgical procedure can trigger myocardial ischemia in susceptible high-risk patients. Intraoperative cardiac monitoring helps to detect signs of ischemia and appropriate oxygenation and measures can be instituted to prevent disasters.

Iatrogenic Emergencies

Incorrect drug administration

Before and during the surgical procedure, drugs may be administered accidentally due to wrong labeling, human fatigue/inattention. This can be avoided by repeated checking and confirming the medication labels, avoiding too many unnecessary medications on the anesthesia machine, adequate rest for the providers and watching for miscommunication during hand-offs.

Incorrect dose administration

This can be a disastrous complication, especially in the case of drugs whose doses are weight dependent or in pediatric/elderly patients or patients with renal or hepatic disease.

Incorrect site of surgery/incorrect surgery

This is a sentinel event and its incidence has increased in recent years. To prevent this from occurring, the following measures have been recommended:

  • Accurately identify patient prior to surgery with two patient identifiers and a “time-out” procedure.
  • Pre-operatively verify the correct patient, surgical procedure and site of surgery from patient documents and implement the process of marking the surgical site with the involvement of the patient and their relatives/family.


This can occur due to inadvertent severance of a blood vessel during the surgical procedure. This can only be prevented by preoperative surgical planning, knowledge of the relevant anatomy, identification of anatomical structures during surgery methodically and requesting for help as needed in an emergency before disaster strikes.

A surgeon can communicate their concern to the anesthesia provider and ensure that adequate fluids and blood products are transfused to maintain blood/plasma volume.

Checklist to Minimize Different Emergencies in the OR

Although certain emergencies are sudden and without apparent cause, the anesthesia provider can pro-actively do the following to minimize nasty operating room surprises:

Evaluate the patient pre-operatively with a thorough history and physical examination. A detailed history will provide information about medications taken by the patient currently, current medical conditions, previous history of allergies, and response to anesthesia for surgical procedures, as well as a family history of medical conditions/response to anesthesia (e.g. delayed recovery from anesthesia).

A physical examination will exclude difficult airway and comorbid medical conditions. If either of these situations is present, then the provider can plan for the anesthesia beforehand.

Maintain a checklist in the operating theater:

  • Confirm the patient’s name.
  • Confirm the patient is adequately fasting.
  • Confirm the site and side of surgery.
  • Ensure that the patient’s intravenous line is functional and correctly positioned.
  • Check the functionality of the anesthesia machine and the adequacy of gasses.
  • Check the availability of the anesthesia agents, intravenous fluids, and cross-matched blood/plasma.
  • Confirm that adequately functioning resuscitation equipment, laryngoscopes, and vacuum suction are available in the OR.
  • Confirm that emergency drugs are readily available if required.
  • Ensure that the correct position of the patient is maintained during anesthesia, as well as during the surgery and that the endotracheal tube is not displaced with any change of the patient’s position.
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