Common Pitfalls Observed During ACLS Certification Exam

Last updated: June 14, 2021

Hands-free pads vs paddles:

Cardiac defibrillation is the delivery of a transthoracic electrical current to a person witnessing ventricular fibrillation (VF).1 Electrical defibrillation is the ultimate treatment for VF which involves the use of hands-free defibrillation pads or defibrillation paddles. Hands-free pads are preferred over paddles due to their potential benefits and efficiency. They allow more rapid defibrillation as compared to defibrillation paddles. Another reason for this preference is that they deliver more energy. The placement of both is the same, in an anteroposterior configuration. Self-adhesive pads significantly decrease the interruption time for safe delivery of the shock during resuscitation of the patient. The decrease in interruptions between cardiac compressions increases the survival rate of the patient. The hands-free pads are thus preferred over defibrillation paddles due to their ease of use and efficacy, as they are responsible for rapid defibrillation and deliver more energy, which ultimately increases the success rate of the shock delivery.2

Placement of defibrillation pads:

In order to restore normal sinus rhythm in a patient having ventricular fibrillation arrest, timely defibrillation is important. The provision of defibrillation involves the usage of hands-free defibrillation pads or defibrillation paddles. The standard placement is that the apical paddle should be placed ‘to the left of the nipple with the center of the electrode in the mid-axillary line’ and the sternal paddle should be placed ‘below the clavicle just to the right of the upper sternal border’.3 Another acceptable position is to place the paddle(labeled “sternum”) in the infrascapular location i.e, posterior to the heart, and to place the “apex” paddle anterior, over the left precordium. During defibrillation placement of electrodes in an anterior lateral position is ideal in all patient-ages. However, if there is a risk of overlapping in defibrillation electrodes (pediatric patients) anterior-posterior electrode placement may be considered.4 Keep the electrodes separated and take care that the gel or the paste applied on the chest is not smeared between paddles, in this case, the current can follow a superficial pathway thus missing the heart. Sticky defibrillator pads are effective in this regard and can be placed in any of these locations.

Determine the correct size of a king airway:

King Airway is 100% latex-free with provided sterile for single patient use. It has the ability to pass a gastric tube through a second channel of the airway into the stomach. It is okay for use with a CPAP device. The device is unlikely to enter the trachea.5 The correct size is chosen on the basis of patients’ height. One should observe the patient’s height to determine the correct size of a King Airway. There is a range of three sizes each ideal for a person with a particular height range. Observing the height of the patient would indicate the correct size of King Airway to be selected for use.

When is cardioversion needed:

Cardioversion converts an abnormal and potentially dangerous rhythm of heart into a normal sinus rhythm. Heart rates that are irregular or the ones that are too fast require cardioversion.6 Cardioversion is also used in critical situations for people who suffer sudden life-threatening arrhythmias. Cardioversion is usually used as a treatment for people with atrial flutter or atrial fibrillation. For hemodynamic deterioration caused by unstable ventricular tachycardia, emergency electrical cardioversion is performed. Hemodynamically unstable Ventricular Tachycardia (VT) requires prompt termination with synchronized cardioversion.7 When vagotonic maneuvers and antiarrhythmic treatments remain unsuccessful for sustained supraventricular tachycardia, electrical cardioversion should be the next step. Electric cardioversion can help the doctors see instantly if the procedure has restored a normal heartbeat also, it takes less time than cardioversion done solely with medications.8 Immediate electrical cardioversion should be considered if the patient is hypotensive, has altered mental status, chest pain, or heart failure.


A do-not-resuscitate (DNR) order is a medical order written by a doctor.9 It instructs that if the patient’s heart stops beating or if a patient’s breathing stops, healthcare providers should not perform cardiopulmonary resuscitation (CPR). Physician order, DNR, or any other hospital directive is never valid outside the hospital. The only valid way to communicate the desire to not be resuscitated is to utilize a special out of hospital DNR (each state has a different form) that is especially approved for use outside of the hospital. Any documentation of desire becomes invalid when the patient leaves the hospital. However, he/she can contact his/her medical command physician (ED physician) to terminate efforts.

Routine administration of high flow oxygen after ROSC:

As per the recent studies, high oxygen concentrations during CPR is preferable during post cardiac arrest care however, hyperoxemia should be avoided.10 Hyperoxemia has caused controversial results in humans. Brain injury is enhanced by the administration of high FiO2 promptly after the return of spontaneous circulation (ROSC) however its administration during CPR results in better quality CPR or better lung function.11 Some studies conclude that hyperoxemia may potentially aggravate or intensify brain injury after experimental cardiac arrest. Thus, it is no longer recommended to routinely administer FiO2 of 100% after CPR.


This page was last reviewed and updated by on Jun 14, 2021.