Anatomy of a Code: A Guide for Nurses Working in Adult Non-Critical Care Units

This is a summary of information for the nursing student, new nurse, or experienced nurse of nursing interventions during a cardiac arrest. It is not an all inclusive guideline of ACLS. It is meant to be a quick summary to ease anxiety related to cardiac arrest. Nurses General Nursing Article


Anatomy of a Code: A Guide for Nurses Working in Adult Non-Critical Care Units

Initial Response:

Oh no! Your patient has gone unresponsive on you. First thing to do is a quick pulse check of their carotid artery.

If you do not detect a pulse within five to ten seconds and your patient wishes to be resuscitated, call for help. Send one person to call the code blue and another to grab the crash cart and defibrillator. Then flatten the bed (max inflate the mattress if you know how) and "jump on their chest" and start compressions. The current Advanced Cardiovascular Life Support (ACLS) guidelines from the American Heart Association call for a compression rate of 100 to 120 compressions per minute.

(If your patient has a pulse, but is not breathing or is breathing very slowly or ineffectively, call for help (code blue) and start providing rescue breaths with a bag valve mask device or "ambu bag" at a rate of one breath every five to six seconds. Give each breath over one second.)

Getting help - time for some delegation!

Make sure your charge nurse and the patient's doctor or provider is aware. Once help arrives, quickly place the patient on the backboard. One staff member should start manually bagging the patient with a bag valve mask device at a compression to ventilation ratio of 30 compressions to two breaths. The other person should hook the patient up to the defibrillator. While your coworker is getting the pads on, continue compressions or switch off with someone if you are tired. In general, someone should switch off doing compressions every two minutes.


There are two popular methods of placing defibrillator pads. The method seen most publicly is anterior-lateral placement. This is usually the method illustrated on the package of the defibrillator pads seen in AEDs. Anterior-lateral placement is great for defibrillation but not for pacing. Anterior-posterior placement is ideal for both pacing and defibrillation, but requires the patient to be turned to place the second pad under the left scapula. When placing the pads, try to avoid nipples. Quickly shave the chest if chest hair is preventing the pads from making contact with skin. Avoid placing the pads over a pacemaker site to avoid damaging the pacemaker.

The defibrillator located on inpatient units generally has two modes. There is the automatic external defibrillator (AED) mode - which is similar in functionality to the AEDs used in the public setting. These defibrillators recognize a fatal arrhythmia and advise a shock if indicated. The other mode is manual where a person who is competent at cardiac arrhythmia recognition recognizes a shockable arrhythmia (either ventricular fibrillation (VF) or "V-fib" or ventricular tachycardia (VT) or "V-tach."). Follow your unit and institutional policies and standards for energy selection if your unit uses defibrillators in manual mode. If using a defibrillator in AED mode, pause compressions while the defibrillator is analyzing the rhythm and then resume compressions until the "all clear" is given before a patient is shocked. As soon as the patient is shocked, compressions should be restarted for a full two minutes. When using a defibrillator in manual mode, compressions need only be paused for the shock and then resumed immediately after defibrillation.

Lots of things to do:

Before the resuscitation team arrives there are a couple things that can be taken care of.

1) Make sure that there is suction set up in the room. It is good practice to have suction set up in your rooms at the beginning of the shift.

2) Get a second and ideally third IV line and draw blood if possible. Have a liter of normal saline hanging and ready at the bedside. It is helpful to have running IV fluids to help flush medications and to make sure the IV is patent. It is also helpful to have some flushes ready.

3) Check a finger-stick blood glucose level. Hypoglycemia is one of the causes of cardiac arrest.

4) Have the patient's labs, previous vital signs, medications, and past medical history at easy access.

When the resuscitation team arrives:

The "code" team is made up of critical care staff and may include nurses, a physician assistant or nurse practitioner, a respiratory therapist, an attending physician/hospitalist and/or a resident physician.

The respiratory therapist should take over bagging the patient. In some hospitals respiratory therapists routinely intubate while in others they just assist with intubation.

The PA or doctor may recommend a 1mg dose of epinephrine. Epinephrine or Adrenaline is a poten vasoconstrictor which is a naturally occurring catecholamine in the body, responsible for the "fight or flight" response of the sympathetic nervous system. Per ACLS protocols, a dose of epinephrine can be given every three to five minutes. The lower concentration of epinephrine (1:10,000) is used for cardiac arrest contrary to the epinephrine in epi pens used for anaphylaxis.

The team will try to find and reverse the possible causes of the cardiac arrest. These are known as the "Hs and Ts."

Other medications given during codes:

Narcan - given to counteract opioid overdose.

Sodium bicarbonate - given for hyperkalemia and acidosis.

Calcium gluconate/calcium chloride - given for hyperkalemia or hypocalcemia or suspected calcium channel blocker/beta blocker overdose.

Magnesium sulfate - given for hypomagnesemia, hypokalemia, V-tach, or Torsades de Pointes.

Dextrose - given for hypoglycemia.

Amiodarone - antiarrythmic sometimes given after the first shock for V-fib or V-tach arrest.

TPA - may be given in the setting of known embolism, pulmonary or otherwise.

Lidocaine - not part of ACLS algorithms, but still given at times for wide complex tachyarrythmias such as V-tach.

IV fluids - given for hypovolemia/support hemodynamics.

Note: When a patient does not have a pulse, there is no need to inquire about a patient's blood pressure. Without a perfusing rhythm, there is no self regulated blood pressure. Effective compressions can create a good blood pressure but any blood pressure measured while the patient is pulseless is really a waste of time.


The patient may be intubated with an endotracheal (ET) tube during or after the resuscitation attempt. Once the patient is intubated, tube verification is done by listening for breath sounds in both lungs and by listening to the stomach to make sure no gurgling is heard (indicating esophageal intubation). Watch for abdominal distention which can indicate esophageal intubation.

Tube placement should also be verified through some sort of carbon dioxide (CO2) detection - either through waveform capnography on the monitor which shows end tidal carbon dioxide (EtCO2) or through a clip attached to the tube and bag valve mask which changes color when it detects carbon dioxide after the patient is bagged a couple times. EtCO2 measures the amount of carbon dioxide present at the end of exhalation and is normally 35 to 45 mmHg. Sometimes it is monitored during resuscitation attempts to gauge the quality of compressions and to help determine if spontaneous circulation returned indicated by a sharp increase in EtCO2.

Once intubation occurs, the patient should continue to be bagged at a rate of six breaths per minute until the ventilator is attached. If the patient survives the resuscitation attempt, final verification of ET tube placement will be done by chest x-ray.


Note: Effective compressions can look a lot like the V-tach shown in the first rhythm video below. Make sure to pause compressions before analyzing the rhythm.

Ventricular Tachycardia (VT) - Rate >100 usually >120, can have pulse, must shock immediately if no pulse or unresponsive.

Torsades de Pointes "Torsades" - A type of VT, no pulse, give magnesium IV push

Ventricular Fibrillation (VF) - No pulse, must shock immediately


After the code:

Most patients do not survive resuscitation attempts. Some survive but with very diminished brain function. Do not expect your patient to wake up after CPR. The ones more likely to wake up right away are those who were successfully shocked immediately after the occurrence of a fatal shockable rhythm like ventricular tachycardia.

To give the patients the best chance of consciousness after cardiac arrest, patients are cooled temperature of 32 to 36 degrees Celsius. The cooling process, also known as targeted temperature management (TMM), is usually initiated in the ICU.

A debriefing process, either directly after the code, a couple hours after the code, or scheduled for another day is a good way to help staff members deal with any feelings they have after the resuscitation and to allow staff members to ask questions.

Sources for information and BLS and ACLS algorithms:

Adult Basic Life Support and Cardiopulmonary Resuscitation Quality

Adult Advanced Cardiovascular Life Support

Here is the link to a good code blue simulation video. I watched several of these and found this one to be the most accurate and informative. Many videos had lapses or delays in compressions that made me cringe.

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Specializes in Med-Surg, Developmental Disorders.

Great article! The only thing I would add is that, while it is true that when there is no perfuming rhythm or patient is pulseless, the patient cannot sustain a viable BP, I have learned in ACLS classes that monitoring BP can also help monitor effectiveness of CPR. IIRC, when the diastolic blood pressure is less than 10, it is a sign of ineffective compressions.

Specializes in Med-Tele; ED; ICU.

Nice summary.

A couple of points that I would add for those who are inexperienced with codes:

1) Every two minutes, *something* should be happening... either meds or a shock...

2) Be sure that *someone* is immediately acting as the recorder. It doesn't necessarily have to be on the code sheet but someone needs to know *when* and *what* right from the inception. This can be as simple as a piece of silk tape on your pant leg or writing on the bed sheet, or even on the drug packages themselves.

3) If you're recording: Keep careful track of time... it's very irritating when the recorder says, "Um, it's been... um... about two minutes..." Also, if you're recording, it can be helpful to give the team a 10-second countdown to the next pulse check, just to minimize the delay and bumbling/fumbling...

4) Don't be afraid to speak up... either with suggestions, delegations, observations, or critiques (particularly of the quality of compressions, which can be hard to maintain/sustain).

Strong post, Lev.

To keep track of medications administered, I suggest not discarding any ampoules or wrappers, keeping them all in a tray for later, when you'll have to write down in some form or another what was done.

I suppose most people have heard this one before, but to understand what the speed of compressions should be, do it in rythm with "Staying Alive" by the BeeGees.

EtCO2 is interesting because it is an early indicator for return of spontaneous circulation (when it will usually skyrocket) and a consistently low EtCO2 during the rescucitation attempts may be indicative of a poor prognosis.

If you can't establish an IV, you can use the endotracheal route (dosage *3 than what would have been used in the IV) - as always, per physician order!

Specializes in Emergency/Cath Lab.

And lest we never forget, my favorite answer to how fast do you push code drugs


Except for Isoprenaline, which isn't a typical code blue drug, but can be used for complete AV bloc (which can be so slow and inefficient that no circulation is taking place); it should be titrated until an acceptable rythm is obtained; if you push it fast, you can overshoot into VTach :)

Thank you! Very informative.