Responsiveness during cardiac arrest presents a real challenge for EMS providers. For some patients, the use of a compression device during CPR can produce enough cardiac output to increase level of consciousness.
This case review presents a patient in cardiac arrest who received immediate bystander CPR and could not be intubated or given IV drugs by paramedics because of his level of consciousness while a compression device was active. The patient received ALS resuscitation, gained ROSC in the prehospital setting and was released from the hospital without any neurological damage. We suggest a treatment option for patients in this unique situation.
The quality of basic life support (BLS) is critical to the outcomes of patients in OHCA.1 One of the most important elements of BLS is delivering high-quality chest compressions during CPR.2
Although the literature is not conclusive about the benefits of mechanical compression devices, many EMS agencies have adopted them.3 The reasons for their adoption are varied and include fatigue of the EMS team while delivering compressions, teams composed of only two providers, and maintenance of high-quality CPR during transport for patients who are quality candidates for advanced hospital procedures such as PTCA (percutaneous transluminal coronary angioplasty), E-ECLS (emergency extracorporeal life support) and potential organ donation.4–7
One consideration with mechanical compression devices is the potential to produce enough cardiac output for patients to regain responsiveness or even feel pain.8 This case review describes a patient in cardiac arrest who was combative during mechanical compressions and the resulting dilemma regarding the use of sedation or analgesia. To date there are no published guidelines for pain management during chest compressions.
Case Report: Witnessed Arrest With Bystander CPR
A 57-year-old physician in a large metropolitan area in Israel collapsed suddenly. An ambulance was dispatched after a call to EMS (see timeline). Two bystander physicians began immediate compression-only CPR, and the patient regained consciousness.
Timeline of Events 17:57 Call to EMS 17:58 Ambulance leaves station 18:06 Ambulance arrives on scene 18:39 Ambulance leaves scene for hospital 18:45 Ambulance arrives at hospital
After a few seconds the patient collapsed again, and compression-only CPR was restarted. The mobile intensive care unit (MICU) dispatched to the scene included four team members: two paramedics, one EMT and a paramedic student. It arrived in less than 10 minutes after the EMS call. The physicians on scene continued delivering compressions until EMS arrived.
EMS found the patient gasping, and immediately one of the team members replaced the physician performing compressions, while another ventilated the patient with a bag-valve device connected to oxygen. The patient was found to be in ventricular fibrillation (VF). A 200-joule biphasic shock was delivered, and BLS continued with minimal interruption while a mechanical compression device (LUCAS 2) was attached to the patient. No medical history for this patient was available on scene.
At this time the patient, still in VF, began moving his hands toward the compression device and grabbed it. While the compressions were paused for ventilation, the patient became flaccid again until the device delivered another compression. The team decided not to intubate the patient, since his level of consciousness indicated it would not be possible without sedation, and concentrated on the quality of BLS delivery.
Efforts to gain vascular access became difficult since the patient had folded his hands and would not allow the paramedics to straighten them. BLS continued without interruption for a total of three rounds of two minutes each, with a total of three 200-joule shocks every two minutes. Without vascular access, no epinephrine was administered, and the airway was managed with an oropharyngeal airway (tolerated for most of the time) and the bag-valve device. At this time the paramedics did not know if sedation by administration of midazolam, etomidate or ketamine was possible for a patient in cardiac arrest, since this situation was never before discussed or encountered. Eventually the paramedics obtained vascular access via an intraosseous device to the left tibia and continued CPR. The patient maintained purposeful movement.
After three shocks and six minutes of CPR, the patient achieved ROSC, and his heart rhythm changed to ventricular tachycardia. Two synchronized shocks were delivered until the rhythm changed to sinus tachycardia with a corresponding pulse. At this time the patient became restless, and the crew administered IO midazolam. The patient was hemodynamically stable, and the electrocardiogram showed no signs of ischemia, ST elevation or other changes suggesting a reason for the cardiac arrest. The nearest hospital’s intensive cardiac care unit advised transport to the ER. On the short ride to the hospital, the patient woke up and was fully aware of what had happened.
At the Hospital
The patient was admitted to the emergency department and transferred to the ICCU. His medical history included rheumatic heart disease, dyslipidemia, a history of smoking, and mechanical aortic and mitral valve replacement. In the last year the patient had experienced a few episodes of paroxysmal atrial fibrillation but was functioning normally, including doing daily exercise. After admission he had no episodes of chest pain, his ECG was normal, and he showed no electrolyte imbalances or QT changes.
The patient’s heart echocardiogram demonstrated new heart failure—a significant change for the worse since his last echocardiogram in 2012, following a mitral valve replacement. The patient’s cardiac coronary computed tomography angiogram (CTA) demonstrated hypertrophy of the septum and a nonrestrictive disease in his coronary arteries. Surgeons implanted a cardioverter-defibrillator, and the patient was released from the hospital with no neurological damage.
While mechanical compression devices have become common in prehospital and hospital treatment, there are no current clinical guidelines for treating patients who regain consciousness during cardiac arrest. This phenomenon presents an interesting challenge for healthcare providers who are not used to treating responsive patients while performing CPR during such arrests. Some of the procedures that are usually performed (such as obtaining vascular access or intubation) require the patient to be unconscious, or at least to not resist treatment.
Currently, cardiac arrest drugs are limited to those intended to restore circulation (vasopressors, antiarrhythmics). The use of mechanical compression devices presents a new challenge that may indicate sedation of patients. Analgesic medications should be selected for minimal cardiovascular influence. Drugs that are currently being used in EMS systems for sedation, analgesia and anesthesia include:
Short-acting benzodiazepines like midazolam and long-acting benzodiazepines like Assival;
Ketamine—for sedation, analgesia and anesthesia;
Etomidate—for general anesthesia and sedation;
Opioids—morphine and fentanyl for analgesia and anesthesia.
We suggest using fentanyl or ketamine for patients who gain some level of consciousness while a mechanical compression device is working.
Fentanyl is a synthetic opioid that is becoming common in EMS systems, as it has sedative and analgesic but minimal cardiovascular effects. While today in some systems it’s administered intranasally for safety reasons, drugs in cardiac arrest should be administered through an intravenous or intraosseous catheter according to current guidelines and since intranasal absorption is probably diminished in cardiac arrest. Ketamine is also a common drug that can provide analgesia and sedation with minimal cardiovascular effects and be used via the IV or IO route.
As mechanical compression devices gain popularity in EMS systems, research in this area should be conducted so clear guidelines can be published and practiced in hospitals and, especially, in prehospital settings.
1. Neumar RW, Otto CW, Link MS, et al. Part 8: Adult Advanced Cardiovascular Life Support—2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation, 2010 Nov 2; 122(18 Suppl 3): S729–67.
2. Meaney PA, Bobrow BJ, Mancini ME, et al. Cardiopulmonary resuscitation quality: improving cardiac resuscitation outcomes both inside and outside the hospital: a consensus statement from the American Heart Association. Circulation, 2013 Jul 23; 128(4): 417–35.
3. Rubertsson S, Lindgren E, Smekal D, et al. Mechanical chest compressions and simultaneous defibrillation vs. conventional cardiopulmonary resuscitation in out-of-hospital cardiac arrest: the LINC randomized trial. JAMA, 2014; 311(1): 53–61.
4. Dallan LA, Vargas TT, Janella BL, et al. Mechanical devices are more effective than manual compressions regarding resuscitation concomitant with emergency percutaneous coronary intervention in cardiac arrest. Circulation, 2014; 130(Suppl 2): A100.
5. Stub D, Bernard S, Pellegrino V, et al. Refractory cardiac arrest treated with mechanical CPR, hypothermia, ECMO and early reperfusion (the CHEER trial). Resuscitation, 2015; 86: 88–94. Wik L, Kiil S. Use of an automatic mechanical chest compression device (LUCAS) as a bridge to establishing cardiopulmonary bypass for a patient with hypothermic cardiac arrest. Resuscitation, 2005; 66(3): 391–4.
6. Mateos-Rodríguez A, Pardillos-Ferrer L, Navalpotro-Pascual JM, et al. Kidney transplant function using organs from non-heart-beating donors maintained by mechanical chest compressions. Resuscitation, 2010; 81(7): 904–7.
7. Bihari S, Rajajee V. Prolonged retention of awareness during cardiopulmonary resuscitation for asystolic cardiac arrest. Neurocritical Care, 2008; 9(3): 382–6.
Oren Wacht, PhD, EMT-P, is clinical coordinator in the department of emergency medicine, faculty of health sciences, Ben Gurion University of the Negev in Israel, and currently a paramedic with Magen David Adom. Reach him at firstname.lastname@example.org.
Refael Huri, EMT-P, is a paramedic with Magen David Adom in Israel.
Refael Strugo, MD, is manager of the medical division of Magen David Adom in Israel.