Cardiopulmonary arrest (CPA) is the cessation of effective ventilation and circulation. It is also known as cardiac arrest or circulatory arrest. In adults, it is most likely to be caused by a primary cardiac event. The most common electrical mechanism which is responsible for 50 to 80% of cardiopulmonary arrest is ventricular fibrillation (VF). While, 20^% to 30% which represents the less common causes of dysrhythmias involve Pulseless electrical activity (PEA), and asystole. Pulseless sustained ventricular tachycardia (VT) is a less common mechanism. This condition could progress to sudden death if it not treated promptly. Nevertheless, a cardiopulmonary arrest (CPA) could be reversed by cardiopulmonary resuscitation and/or cardioversion or defibrillation, or cardiac pacing.[1]
The American Heart Association's AHA periodically releases updates and recommendations for adult basic life support (BLS) and the quality of cardiopulmonary resuscitation (CPR) on adults. Despite the causes, early induction of cardiopulmonary resuscitation (CPR) along with cardiac monitoring will determine which pulseless arrest pathway one has to follow. Evidence suggests that more than 400000 people die of cardiopulmonary arrest in the U.S every year.[2] They may or may not have been diagnosed with cardiopulmonary disease.
There are various causes for cardiopulmonary arrest in adults which varies by age and population. However, patients diagnosed with cardiac disease are more susceptible to having a cardiac arrest. Furthermore, it can be classified into different categories, which include cardiac, respiratory, and traumatic causes. But 75% of cardiac arrest incidents are believed to be due to coronary artery diseases.[2]
Cardiac Causes
Coronary Artery Disease
Coronary artery abnormalities:
Myocardial Infarction:
Myocardial Hypertrophy
Valvular Heart Disease
Infiltrative and Inflammatory Disorders
Dilated Cardiomyopathy
Electrophysiologic Abnormalities
Inherited Disorders
Heart Failure
Congenital disease
Respiratory Causes
Traumatic Causes
Overall, the prevalence of cardiac causes is around 50% to 60%. Whilst, the second most common cause that is respiratory insufficiency is around 15% to 40%.[4]
Cardiac arrest is divided into out-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA). However, the incidence of cardiopulmonary arrest worldwide is not well described. In the U.S, more than 290,000 IHCA occur in adults annually, whilst 326,000 cases of OHCA among adults occur yearly. Half of these are unwitnessed.[4][5]
Men and women in middle-age have different susceptibilities to cardiopulmonary arrest; however, the sex differences decrease with increasing age. The difference in risk for cardiopulmonary arrest collateral the variations in age-related risks for other features of coronary heart disease (CHD) between males and females. As the gender gap for signs of coronary heart disease closes in the 6th to 8th decades, the excess risk of arrest in males progressively narrows. In spite of the lower incidence among younger women, CHD risk factors such as diabetes (DM), cigarette smoking, hyperlipidemia, and hypertension (HTN) are very highly influential.
Data from postmortem examinations of cardiopulmonary arrest and sudden cardiac death (SCD) victims correlate with the clinical observations on the prevalence of coronary artery disease as the major structural etiologic factor. Higher than 80% of victims have pathologic findings of coronary artery disease. The pathologic description often involves a combination of extensive atherosclerosis of the coronary arteries along with unstable coronary artery lesions, which include various permutations of fissured, eroded, or ruptured plaques; and/or thrombosis. As many as seventy percent of men who die suddenly have preexisting healed myocardial infarctions, whereas only twenty percent have recent acute MIs, in spite of the prevalence of thrombi and unstable plaques.[6]
In numerous patients, warning signs and symptoms may precede a cardiac arrest. Nevertheless, these features are ignored and unrecognized several times because those who survive after experiencing cardiopulmonary arrest, many of them suffer from amnesia while those patients who suffered cardiopulmonary arrest but survived and remember the event reveals that the most common sign was palpitations, shortness of breath, nausea, and chest pain.
Clinicians examing cardiopulmonary arrest should start head-to-toe assessment immediately which will help to formulate the plan of management. The physical examination will help to diagnose the cardiopulmonary arrest as well as provide the most important information regarding the possible cause and the prognosis. While, the history will help to delineate at what time the event took place, what the victim was doing, and the involvement of drugs. In many cases, the gold standard for diagnosing the cardiopulmonary arrest is the loss of carotid pulse, But, many studies have shown that the rescuers often make a mistake while checking the carotid pulse, whether they are laypersons or the healthcare professionals.[7]
Cardiopulmonary resuscitation should not be interrupted for doing blood or radiological investigation. However, point of care testing, like blood glucose or serum potassium may be done if it doesn't interfere with cardiopulmonary resuscitation efforts. Point of care ultrasound can also be used to evaluate the activity of the heart during cardiopulmonary resuscitation which has proved beneficial in many studies.[8]
Five stages in the management of the patient with confirmed cardiopulmonary arrest are:
Once the diagnosis of cardiopulmonary arrest is confirmed, then basic life support (BLS) and defibrillation can be carried out by the public, physicians, paramedical personnel, trained laypersons, and nurses. There is an increasing demand for specialized skills such as Advanced Life Support (ALS), post-resuscitation care, and long-term management of post cardiopulmonary arrest patients. The cardiopulmonary arrest could be reversed by two main interventions, i.e., early CPR and early Automated external defibrillation (AED). The first step involves recognition of the cardiopulmonary arrest and the BLS measures. If defibrillation is available for public use, then it should be activated and used if needed. Next, advanced life support (ALS) measures are used, involving IV/IO medication administration. If spontaneous circulation returns, then the case will undergo post-resuscitation care along with subsequent long-term management. The identification of a cardiopulmonary arrest victim includes ensuring that the patient is unresponsive, pulseless, and having abnormal breathing. Once the patient is identified, immediate CPR and activation of the Emergency Medical Services (EMS) should be done promptly. Nowadays, public access to defibrillation has been adding another layer of response.
Initial Evaluation and BLS
Confirming cardiopulmonary arrest need careful examination of the patient's level of consciousness, skin color, breathing movement, and arterial pulse either in the carotid or femoral artery. Just after confirming the arrest, the immediate responsibility of the rescuer is to call Emergency Medical Services and start CPR.
It is essential to diagnose the signs of aspirations of a foreign body in the respiratory tract, which includes severe stridor, dyspnea, suprasternal and intercostal retractions. It is recommended to do the Heimlich maneuver if we are suspecting aspiration.
Maintaining a patent airway is necessary for successful cardiopulmonary resuscitation. Maneuvers like chin lift, head tilt, and jaw thrust can be used to keep the airway patent. Any visible foreign bodies like displaced dentures should be removed from the oropharynx. Ventilatory aids like oropharyngeal airway (OPA) and the nasopharyngeal airway (NPA) may be used if the rescuer is experiencing difficulty in ventilating the patient.[9][10]
The AHA guideline suggested certain recommendation for doing high-quality CPR:[11]
Automated External Defibrillation
The AEDs are easily handled via nonconventional responders, for instance: ambulance drivers, police officers, firefighters, security guards, and laypersons. Recent studies have suggested that AED use via nonconventional responders could improve the survival rates of cardiopulmonary arrest as the arrival of the ALS team takes time, and early defibrillation by non-conventional responders will not only reduce the time for defibrillation but will also improve patient outcome.
Advanced Cardiac Life Support
Providers can use basic life support along with advanced airway aid and medication like epinephrine and amiodarone for CPR. The advanced airway may include supraglottic airway devices and endotracheal tubes. ACLS team has the further advantage of cardiac rhythm interpretation and using defibrillation when indicated.
ADVANCED CARDIAC LIFE SUPPORT (ACLS) is designed to deliver adequate ventilation, stabilize the blood pressure along with the cardiac output, control cardiac arrhythmias, and restore organ perfusion. Maneuvers needed to accomplish these goals include-
The rapidity by which defibrillation is performed is an essential element for improving patient outcomes. The AHA guideline suggested certain recommendation for defibrillation-
After failed defibrillation, epinephrine, 1mg I/V, should be given. Furthermore, the dose of this drug may be repeated after periods of three to five minutes. Additionally, vasopressin has been recommended as an alternative.[12]
After 2 or 3 failed attempts, immediate intubation and arterial blood gas analysis should be carried out. Those patients who still remain acidotic even after intubation and successful defibrillation should be given 1 new/ kg of NaHCO3 initially, and further 50 percent of the dose may be repeated after 10 minutes.
Antiarrhythmic therapy with amiodarone may be started after recurrent electrical instability and failed defibrillation. 150 mg amiodarone should be given over 10 minutes, followed by 1 mg/ hr for 6 hours and 0.5 mg/ hour for the next 18 hours. Procainamide is rarely used nowadays. Calcium gluconate is not considered safe, and its use is only reserved for patients having hyperkalemia or have taken a lethal dose of calcium channel blocker.[13]
Postresucitation Care
This phase starts with the successful return of spontaneous circulation. Generally, the Primary ventricular fibrillation after acute myocardial infarction( AMI) are highly responsive to treatment and are readily controlled while in secondary ventricular fibrillation after AMI, resuscitative efforts are usually less successful, and those patients who are resuscitated successfully, the rate of recurrence of VF is very high. Patient outcome is determined by hemodynamic stability. Asystole, bradyarrhythmias, and PEA are commonly seen in hemodynamically unstable patients.[14]
The outcomes and the clinical picture after In-hospital cardiopulmonary arrest (IHCA) associated with the noncardiac diseases are very poor, and in some successfully resuscitated cases, the post-resuscitation course is controlled by the nature of the underlying illness. Patients with cancer, central nervous system disease, renal failure have a survival rate of less than ten percent after IHCA.
Long-Term Management After The Survival Of OHCA
Patients who survive cardiopulmonary arrest without irreversible damage to the brain must undergo proper investigation in order to know the etiology and definite intervention so that such episodes can be prevented in the future.
Patients with cardiopulmonary arrest due to myocardial ischemia should be managed by surgical, pharmacological ( anti ischemia therapy), and radiological intervention so that long term survival can be improved.
Survivors of cardiopulmonary arrest due to diseases, like hypertrophic cardiomyopathies, rare inherited disorders, right ventricular dysplasia, catecholaminergic polymorphic VT, Brugada syndrome, and long QT syndrome, are the candidates for Implantable cardioverter-defibrillator (ICD).
Patients with cardiopulmonary arrest will be pulseless and unresponsive. But there are certain conditions having clinical manifestations similar to cardiopulmonary arrest. It includes syncope, seizure, and overdose of certain medications like opioids.[1] We should try to recognize and treat reversible causes of cardiopulmonary arrest commonly referred to as Hs and Ts. It includes-
Witnessed cardiopulmonary arrest along with immediate CPR and defibrillation have better patient survival and outcome.[15] Healthy and young patients are more likely to obtain the return of spontaneous circulation as compared to elderly patients with known co-morbidities such as IHD.
Various complications can occur during cardiopulmonary resuscitation. AED failure is the most common complication. Other complications include the inability to obtain venous access, rib fracture, pneumothorax, pneumomediastinum, hemothorax, lung laceration, pulmonary hemorrhage, injury to the major vessel, and cardiac tamponade.
Most of the cardiopulmonary arrest occur outside hospitals. Immediate cardiopulmonary resuscitation and defibrillation are the two main intervention which has shown to improve patient outcomes.[16][17] Hence, even laypersons with adequate CPR skills and training can save lives. But, sometimes even the trained person hesitate to start CPR because of a lack of confidence and cardiac arrest recognition.[18] This points to the need for improving their skills and confidence by organizing regular training sessions and workshops.
The vast majority of patients who experience cardiopulmonary arrest are known cases of coronary artery disease. Cardiopulmonary arrest in such patients can be prevented by reducing the progression of the disease by altering modifiable risk factors and regular medication. In addition, healthcare professionals should educate the patient about the advantages of a healthy diet, regular exercise, effective treatment of dyslipidemia, hypertension (HTN), diabetes (DM), and smoking cessation. Finally, it is the responsibility of healthcare professionals to be well versed with the basic principles and clinical skills needed for effective cardiopulmonary resuscitation.[19]
[1] | Patel K,Hipskind JE, Cardiac Arrest 2020 Jan; [PubMed PMID: 30521287] |
[2] | State-specific mortality from sudden cardiac death--United States, 1999. MMWR. Morbidity and mortality weekly report. 2002 Feb 15; [PubMed PMID: 11898927] |
[3] | Katritsis DG,Gersh BJ,Camm AJ, A Clinical Perspective on Sudden Cardiac Death. Arrhythmia [PubMed PMID: 28116082] |
[4] | Andersen LW,Holmberg MJ,Berg KM,Donnino MW,Granfeldt A, In-Hospital Cardiac Arrest: A Review. JAMA. 2019 Mar 26; [PubMed PMID: 30912843] |
[5] | Goyal A,Sciammarella JC,Cusick AS,Patel PH, Cardiopulmonary Resuscitation (CPR) 2020 Jan; [PubMed PMID: 29261985] |
[6] | Neth MR,Benoit JL,Stolz U,McMullan J, Ventilation in Simulated Out-of-Hospital Cardiac Arrest Resuscitation Rarely Meets Guidelines. Prehospital emergency care : official journal of the National Association of EMS Physicians and the National Association of State EMS Directors. 2020 Oct 6 [PubMed PMID: 33021857] |
[7] | Iwashita M,Waqanivavalagi S,Merz T,Jones P, Eligibility criteria for extracorporeal cardiopulmonary resuscitation at Auckland City Hospital: A retrospective cohort study. Emergency medicine Australasia : EMA. 2020 Oct 5 [PubMed PMID: 33021065] |
[8] | Gaspari R,Weekes A,Adhikari S,Noble VE,Nomura JT,Theodoro D,Woo M,Atkinson P,Blehar D,Brown SM,Caffery T,Douglass E,Fraser J,Haines C,Lam S,Lanspa M,Lewis M,Liebmann O,Limkakeng A,Lopez F,Platz E,Mendoza M,Minnigan H,Moore C,Novik J,Rang L,Scruggs W,Raio C, Emergency department point-of-care ultrasound in out-of-hospital and in-ED cardiac arrest. Resuscitation. 2016 Dec; [PubMed PMID: 27693280] |
[9] | Guildner CW, Resuscitation--opening the airway. A comparative study of techniques for opening an airway obstructed by the tongue. JACEP. 1976 Aug; [PubMed PMID: 1018384] |
[10] | Uzun L,Ugur MB,Altunkaya H,Ozer Y,Ozkocak I,Demirel CB, Effectiveness of the jaw-thrust maneuver in opening the airway: a flexible fiberoptic endoscopic study. ORL; journal for oto-rhino-laryngology and its related specialties. 2005; [PubMed PMID: 15753621] |
[11] | Kleinman ME,Brennan EE,Goldberger ZD,Swor RA,Terry M,Bobrow BJ,Gazmuri RJ,Travers AH,Rea T, Part 5: Adult Basic Life Support and Cardiopulmonary Resuscitation Quality: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2015 Nov 3; [PubMed PMID: 26472993] |
[12] | Long B,Koyfman A, Emergency Medicine Myths: Epinephrine in Cardiac Arrest. The Journal of emergency medicine. 2017 Jun [PubMed PMID: 28174032] |
[13] | [PubMed PMID: 27043165] |
[14] | [PubMed PMID: 26385451] |
[15] | de Vreede-Swagemakers JJ,Gorgels AP,Dubois-Arbouw WI,Dalstra J,Daemen MJ,van Ree JW,Stijns RE,Wellens HJ, Circumstances and causes of out-of-hospital cardiac arrest in sudden death survivors. Heart (British Cardiac Society). 1998 Apr; [PubMed PMID: 9616342] |
[16] | Berg RA,Hemphill R,Abella BS,Aufderheide TP,Cave DM,Hazinski MF,Lerner EB,Rea TD,Sayre MR,Swor RA, Part 5: adult basic life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010 Nov 2; [PubMed PMID: 20956221] |
[17] | Zhan L,Yang LJ,Huang Y,He Q,Liu GJ, Continuous chest compression versus interrupted chest compression for cardiopulmonary resuscitation of non-asphyxial out-of-hospital cardiac arrest. The Cochrane database of systematic reviews. 2017 Mar 27; [PubMed PMID: 28349529] |
[18] | Wik L,Kramer-Johansen J,Myklebust H,Sørebø H,Svensson L,Fellows B,Steen PA, Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest. JAMA. 2005 Jan 19; [PubMed PMID: 15657322] |
[19] | Sandhu RK,Jimenez MC,Chiuve SE,Fitzgerald KC,Kenfield SA,Tedrow UB,Albert CM, Smoking, smoking cessation, and risk of sudden cardiac death in women. Circulation. Arrhythmia and electrophysiology. 2012 Dec; [PubMed PMID: 23233741] |