Cardiac Surgical Unit Advanced Life Support Protocol

Educational Objectives

The goal of this program is to improve the utilization of the Cardiac Surgical Unit Advanced Life Support (CSU-ALS) protocol in patients after cardiac surgery. After hearing and assimilating this program, the clinician will be better able to:

1. Compare internal with external cardiac massage.
2. Explain the role of the medication administrator in the CSU-ALS protocol.
3. Manage shockable cardiac arrest in a patient after cardiac surgery using the CSU-ALS protocol.

Summary

Introduction: the Cardiac Surgical Unit[-Advanced Life Support (CSU-ALS) protocol was developed by Dr. Joel Dunning in the United Kingdom in the early 2000s; the CSU-ALS protocol was endorsed by the Society of Thoracic Surgeons in 2017; common causes of postoperative cardiac arrest, eg, tamponade, hypovolemia, tension pneumothorax is poorly addressed by external cardiac massage (ECM); CSU-ALS emphasizes rapid re-opening of the chest (resternotomy) as the most effective intervention; cardiac arrest after cardiac surgery has higher survival rate than both out of hospital (≈326,000) and in-hospital arrests (≈200,000); this may be attributed to the high incidence of readily reversible causes, and the prevalence of shockable rhythms in patients after surgery patients

Evidence: Mackay et al (2002) recommended reopening ≤10 min, based on a series of re-sternotomies over 6 yr; another analysis of 72 re-sternotomies over 4 yr recommended rapid restoration ≤5 min

Protocol: the CSU-ALS protocol has 3 main subdivisions; for patients with a shockable rhythm, the protocol recommends delivering 3 stacked shocks without the 2 min of CPR typically used in advanced cardiovascular life support (ACLS); if these shocks are unsuccessful, then basic life support is initiated, and preparations are made to open the chest; in cases of bradycardia or asystole after cardiac surgery, especially if epicardial pacing wires are present, pacing is attempted; in the shockable rhythm and bradycardia or asystole scenarios, external cardiac massage may be delayed for ≤60 sec to allow for initial interventions; this 60 sec delay is a key difference from standard ACLS and is based on the rationale that immediate intervention (shocks or pacing) may be more effective and less damaging than external chest compressions in this patient population; in patients with pulseless electrical activity (PEA), basic life support is started immediately, and preparations for re-sternotomy are begun; PEA in this context implies a surgically correctable cause, eg, bleeding, tamponade; regardless of the initial rhythm, if 60 sec have elapsed without successful intervention, chest compressions must be started while the chest is being opened; evidence suggests that the success rate of defibrillation decreases with each subsequent shock; if the stacked shocks fail to restore a perfusing rhythm ≤60 sec, then cardiopulmonary resuscitation (CPR) is started, and the chest is opened; the standard ACLS mandates 2 min of CPR before each rhythm check and shock

Evidence: early defibrillation without 2 min of CPR between shocks showed significantly improved survival to discharge compared with the ACLS approach; another multicenter retrospective study of in-hospital cardiac arrests because of ventricular fibrillation or pulseless ventricular tachycardia showed that 3 stacked shocks resulted in more frequent return of spontaneous circulation (ROSC) and improved survival to discharge

Pacing: patients after cardiac surgery often have epicardial pacing wires, making pacing a viable option for bradycardic or asystolic arrests; in these situations, chest compressions may be delayed for ≤60 sec; the clinician may use the emergency button on the pacemaker to check pacing wire functionality; if pacing (or any other intervention) is not successful within that timeframe, chest compressions must be initiated; the rationale for delaying CPR is to avoid potentially fatal complications associated with external chest compressions in these patients; recent sternotomies, bone spurs, and the presence of grafts (eg, left internal mammary artery) make external compressions particularly risky; it is preferable to address the cause directly

Cardiac massage: internal cardiac massage (ICM) is superior to ECM; it allows for direct treatment of common causes of cardiac arrest; evidence suggests that ICM achieves higher coronary perfusion pressure and better organ blood flow, leading to increased likelihood of ROSC; case study (Paradis et al [1990]) indicated a pressure difference of 15 mm Hg between the aorta and right atrium is necessary, though not guaranteed, for ROSC; since ICM achieves significantly higher pressures (≈30 mm Hg) compared with ECM (≈6 mm Hg), it is theorized to be more effective; evidence showed successful resuscitation in 3 of 10 patients declared dead after failed ECM when ICM was used; there is insufficient evidence to recommend abdominal compression

Cerebral perfusion: is crucial during resuscitation; evidence suggests that open cardiac massage significantly improves cerebral perfusion pressure compared with closed cardiac massage; epinephrine is used in standard ACLS; it is discouraged in this protocol because of the lack of proven survival benefit and increased bleeding risk; when used, much lower doses (50-100 μg) are preferred; atropine is not recommended because of lack of proven benefit and potential delays in definitive treatment; amiodarone may be used for ventricular fibrillation and tachycardia after 3 shocks, at the discretion of the clinician, but should not delay chest opening if indicated

CSU-ALS team: the protocol uses a 6-person “pit crew” model, 1) the bedside provider, 2) airway provider, 3) defibrillation or pacing provider, 4) team leader, 5) person for medications, and 6) intensive care unit (ICU) coordinator

The bedside nurse: initiates the code, calls for help, starts ECM, and prepares for defibrillation or pacing; ECM should be performed at standard ACLS rates, and its effectiveness monitored; if systolic pressure >60 mm Hg is not achieved, immediate resternotomy is recommended because of the increased likelihood of tamponade or hypovolemia

Airway provider: initially removes the patient from the ventilator and uses bag mask ventilation to assess the endotracheal tube (ET) for proper placement and function; one must rule out the ET tube as the cause of the arrest; after assessment, the patient may be placed back on the ventilator with 100% fraction of inspired oxygen (FiO₂) and 0 positive end expiratory pressure (PEEP) to decrease intrathoracic pressure and improve ROSC; this flexibility is included in the protocol to accommodate situations with limited staff; in practice, continuous bag mask ventilation is preferred if sufficient staff are available

Person responsible for defibrillation or pacing: manages all electrical interventions, including connecting the defibrillator, administering shocks (as directed), and managing the pacemaker if needed; they are responsible for placing internal defibrillator paddles onto the sterile field once the chest is prepared and ready to be opened

Team leader: responsible for directing the code; while ideally the senior clinician, the role can be filled by anyone trained in the protocol; the team leader focuses on clear communication, minimizing room traffic, and ensures the thoracotomy cart is opened and 2 individuals begin sterile preparation for opening the chest

Medication management: a key aspect, initially controversial but now accepted practice, is the immediate cessation of all infusions upon recognizing the arrest; this eliminates potential medication errors as a cause of the arrest; medications can be restarted later; this person may administer amiodarone and low-dose epinephrine as directed

The ICU coordinator: manages activities outside the immediate bedside area; they identify 2 individuals to prepare for a thoracotomy (eg, charge nurse), ensuring they are ready to open the chest immediately if needed; this happens concurrently with other resuscitation efforts; the coordinator also notifies the attending surgeon to come to the bedside; in situations with limited personnel, individuals may need to assume multiple roles

Emergency resternotomy: for nonshockable cardiac arrests where reversible causes have been ruled out, emergency resternotomy should ideally be performed ≤5 min; emergency resternotomy allows ICM; extracorporeal membrane oxygenation (ECMO) is a viable alternative in institutions with ECMO capabilities; it may create complex decisions, especially in complex post-surgery patients; ideally, the surgical team’s preference (resternotomy vs ECMO) should be clarified before a code event, particularly in high risk patients; emergency resternotomy is needed in ≤2.7% of patients after cardiac surgery; all personnel involved in a code should be trained in the procedure; the resternotomy tray contains scalpel, wire cutter, heavy needle holder, thermal retractor, and suction device; immediately upon recognizing the arrest, 2 to 3 staff members should begin preparing for procedure; aseptic technique is preferred, and speed is prioritized; hand washing is generally not deemed necessary if closed glove technique is used; skin preparation is usually skipped because of the risk for fire with improperly dried preparatory solution

Procedure: the person performing external cardiac massage moves aside; one person applies the all in one drape with the chest opening, while the other makes a straight incision down to the sternal wires; the wires are cut and removed, and if it is a tamponade event, the sternum often falls open; excess clot and blood are suctioned, the sternal retractor is placed, and the sternum is opened; once inside, structures, eg, LIMA graft need to be identified and protected; ICM is performed if ROSC is not achieved

Note: this protocol is generally not recommended outside the ICU because of the complexity and the need for trained personnel; other aspects of the protocol must be applied in these settings; the protocol is typically recommended for the first 10 postoperative days; after this period, significant adhesions develop, increasing the risk for emergent re-entry into the chest by untrained personnel; after 10 days, the decision to perform an emergent resternotomy rests with the attending surgeon

Special considerations: include intraaortic balloon pumps (IABPs); the IABP’s pumping action may create a pulse, potentially masking the absence of true forward flow during an arrest; IABP may be paused to confirm the arrest; if the IABP is triggered by electroencephalography and the patient experiences an arrhythmia leading to arrest, the trigger should be switched to pressure-triggered to avoid exacerbating the situation; for patients after cardiac transplantation, clamshell incisions are reopened according to the same guidelines as other sternotomy patients; primary sternotomies in the ICU, however, should only be performed by an attending surgeon or a surgical fellow under direct supervision; in complex cases (eg, ventricular assist devices [VADs], multiple resternotomies, specialized closure devices), a sign should be placed outside the patient’s room indicating the plan of action in case of an arrest, as determined by the attending surgeon; patients with VADs or other cardiac assist devices are generally resuscitated using the same principles and the CSU-ALS protocol; however, recognizing an arrest in a patient post VAD can be challenging; cerebral blood flow can be maintained even during ventricular fibrillation in some cases; having personnel available who are trained to troubleshoot the specific VAD is essential; for nonsternotomy cardiac surgery patients, ECMO remains an option in facilities that offer it; primary surgical re-entry in the ICU without a surgeon present is strongly discouraged

Implementation: of the protocol and guidelines requires a transition phase, especially for experienced providers accustomed to ACLS protocols; one of the main safety concerns is the “3-stack” defibrillation protocol, which differs from standard ACLS and can pose a risk to staff if not performed correctly

Readings

Brand J, McDonald A, Dunning J. Management of cardiac arrest following cardiac surgery. BJA Educ. 2018;18(1):16-22. doi:10.1016/j.bjae.2017.11.002; Fairman RM, Edmunds LH Jr. Emergency thoracotomy in the surgical intensive care unit after open cardiac operation. Ann Thorac Surg. 1981;32(4):386-391. doi:10.1016/s0003-4975(10)61761-4; Mackay JH, Powell SJ, Osgathorp J, et al. Six-year prospective audit of chest reopening after cardiac arrest. Eur J Cardiothorac Surg. 2002;22(3):421-425. doi:10.1016/s1010-7940(02)00294-4; Michaelis P, Leone RJ. Cardiac arrest after cardiac surgery: an evidence-based resuscitation protocol. Crit Care Nurse. 2019;39(1):15-25. doi:10.4037/ccn2019309; Paradis NA, Martin GB, Rivers EP, et al. Coronary perfusion pressure and the return of spontaneous circulation in human cardiopulmonary resuscitation. JAMA. 1990;263(8):1106-1113; Soar J, Böttiger BW, Carli P, et al. European resuscitation council guidelines 2021: adult advanced life support [published correction appears in resuscitation. 2021 Oct;167:105-106. doi: 10.1016/j.resuscitation.2021.08.011.]. Resuscitation. 2021;161:115-151. doi:10.1016/j.resuscitation.2021.02.010; Society of Thoracic Surgeons task force on resuscitation after cardiac surgery. The Society of Thoracic Surgeons expert consensus for the resuscitation of patients who arrest after cardiac surgery. Ann Thorac Surg. 2017;103(3):1005-1020. doi:10.1016/j.athoracsur.2016.10.033; Yadava OP, Levine AJ. CSU-ALS protocol for cardiac arrest. Indian J Thorac Cardiovasc Surg. 2021;37(4):471-472. doi:10.1007/s12055-021-01221-1.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Lester was recorded at the 2024 Annual Convention and Conclave of the American Osteopathic College of Anesthesiologists, held September 7-10, 2024, in Palm Springs, CA, and presented by the American Osteopathic College of Anesthesiologists. For information on upcoming CME activities from this presenter, please visit aocaonline.org. Audio Digest thanks the speakers and American Osteopathic College of Anesthesiologists for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 1.25 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 1.25 CE contact hours.

Lecture ID:

AN671301

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.