The Two-Person Response to SCA

Sudden cardiac arrest is among the most serious life-threatening conditions but one of the best refined in how it’s treated. Implementation of immediate algorithms for management is difficult yet feasible with team cooperation and practice.

West Pomeranian Voivodeship is located in the northwestern part of Poland, on the coast of the Baltic Sea. It covers an area of more than 8,800 square miles and has roughly 1.71 million inhabitants. In Szczecin there is a provincial emergency service station (WSPR), the head of which, Roman Pałka, is a medical doctor. WSPR Szczecin has 79 ALS-equipped medical rescue teams. For over a dozen years, the station directorate has been implementing pioneering programs in the field of medical rescue such as continuous first aid training among residents, including preschool children, and advanced training for employees aimed at ensuring the highest quality health services. WSPR Szczecin was one of the first in Poland to introduce platforms for mechanical chest compressions in all ambulances. 

Sudden cardiac arrest is the leading cause of death in Europe and the world. Among adults the most common mechanism of cardiac arrest, in almost 75% of cases, is ventricular fibrillation (VF) or ventricular tachycardia without palpable heart rate (VT). About 15% relate to asystole, and 10% pulseless electrical activity (PEA). In nonhospital VF the rhythm is found in about 40% of cases. Time is of utmost importance here, and delayed assistance, especially in the absence of witnesses or when CPR is slow to begin, decreases survival to hospital discharge to only 10%.

About 70%–80% of out-of-hospital SCAs take place in the home, and as many as two-thirds occur during the day, which increases the chance of early notification by witnesses. There should be no more than five minutes from the first symptoms of cardiac arrest and breathing failure until rescue operations are undertaken; that’s why it’s so important to educate the public about first aid. Rescuers often take more than five minutes to arrive, and bystander resuscitation would increase thousands of victims’ chances of successful outcomes. 

Case Description

A call-taker at the central medical dispatch center in Szczecin received a call for a man in a restaurant. While eating dinner, he’d “begun to cough, turned blue, and fell to the floor.” The dispatcher instructed witnesses to begin CPR and sent an ALS-equipped emergency medical team consisting of two rescuers. 

At the scene the team found a man about 50 years old lying in horizontal position with visible cyanosis of the face and three family members performing indirect cardiac massage along with rescue breaths according to dispatcher instructions. After assessing the place for safety, the rescuers started medical rescue operations: The paramedic (rescuer #1), who located himself near the chest, thanked the witnesses for undertaking resuscitation and checked the man for breathing, finding none. The rescuer behind the head (rescuer #2) checked the carotid artery and found no pulse. 

As rescuer #1 began chest compressions, rescuer #2 assembled an oxygen set and delivered two breaths, then called dispatch to summon a specialist team consisting of a doctor and two additional rescuers. Rescuer #2 applied electrodes and activated the defibrillator. Rescuer #1 evaluated the rhythm on the monitor and rechecked the carotid artery, finding PEA, then returned to chest compressions. Rescuer #2 obtained IV access and delivered two breaths, then prepared and administered 1 mg of IV adrenaline, followed by two more breaths, after which rescuer #1 began indirect heart massage. Rescuer #2 prepared and administered an infusion of 0.9% NaCl and provided breaths during breaks in the heart massage. 

After a two-minute loop of advanced rescue operations, rescuer #1 rechecked the heart rate and rhythm on the monitor. The patient was still in PEA. The rescuers exchanged positions. 

Asphyxia-Related Cardiac Arrest

Cardiac arrest rarely results from hypoxemia only. The most frequent reason is asphyxia. The above case was caused by obstruction of the airway by a foreign body. This is associated with both hypoxemia and hypercarbia, but the first is the direct cause of cardiac arrest. Obstruction of the trachea causes inability to breathe, and within 1–2 minutes saturation falling to about 60% results in loss of consciousness and respiratory arrest. Pulseless electrical activity appears within 3–11 minutes, then, without appropriate resuscitation, asystole. VF is rarely the first rhythm in the case of asphyxia-related cardiac arrest. 

After each compression we allow the chest to return to its correct shape. We do not take our hands off the chest, we try not to lean on the chest, we minimize breaks in the pressure, and in order to ensure high-quality heart massage, we change the person squeezing every single loop, approximately every two minutes.

Second Loop

Rescuer #1 performed heart massage at a frequency of 30 presses. Rescuer #2 placed an alternative airway (or would intubate, depending on experience), placed a capnometer and performed three breaths. Rescuer #1 auscultated the area around the stomach and lung field to confirm correct placement of the tracheal tube/alternative, then returned to compressing. Rescuer #2 performed two breaths; rescuer #1 performed massage; rescuer #2 gave two more breaths; rescuer #1 pressed the chest. This cycle continued until rescuer #1 stopped to evaluate the rhythm and rate. The rescuers again exchanged positions. 

During intubation, a short pause in compressions is allowed to provide about five seconds for insertion of the endotracheal tube. After securing airway patency it is recommended to ventilate the patient at about 10 breaths per minute.

Third Loop

Rescuer #2 installed a platform for mechanical chest compressions, preventing the reduction of CPR quality. The rescuers continued to change positions every fifth cycle (two minutes). Rescuer #2 provided the next dose of 1 mg adrenaline, and with placement of the automated chest compression device (time elapsed since arrival: seven minutes), rescuer #1 was freed from performing the indirect heart massage and could begin searching for reversible causes of cardiac arrest. Rescuer #2 provided patient ventilation in accordance with the above recommendations. 

During the third loop of cardiopulmonary resuscitation, we seek and treat reversible causes of cardiac arrest using the familiar “4Hs and 4Ts” abbreviation: hypoxia, hypo-/hyperkalemia and other electrolyte disorders, hypo-/hyperthermia, hypovolemia, tension pneumothorax, pericardial tamponade, thrombosis, and toxins.

Fourth Loop

After five cycles (10 minutes) of CPR, the patient experienced spontaneous circulation return. The monitor showed sinus rhythm at a frequency of 160/min., with a well-felt heart rate on the carotid and radial arteries, blood pressure of 110/60, blood glucose level of 180 mg/dL, facial grimace to pain, and Glasgow score of 7 (eyes 2, verbal 1, reaction 4). The specialist team arrived during the fourth loop of CPR and took over care. 

Summary

With a two-person team, the division of roles is important. The rescuer at chest level (rescuer #1) performs chest compressions and, after about two minutes (or five cycles), assesses the rhythm on the monitor. Rescuer #2, behind the head of the victim, performs ventilation, obtains IV access, and administers drugs per the algorithm. This arrangement ensures the medicines will be administered by the rescuer behind the head and the rescuer pressing on the rib cage can focus on the appropriate pace and depth.

Synchronous ventilation is preferred to asynchronous because breaths are delivered at the right time, and while one of the rescuers presses the chest, the other behind the head can perform other tasks.
 
When performing asynchronous ventilation, remember that the time between breaths in an adult is 6–8 seconds, and in order to perform the full ALS procedure, we must remember to establish intravascular access and supply drugs in accordance with the guidelines. The time we have between breaths is too short to perform the above activities in a safe manner, and in practice it means skipping a few breaths. In addition the quality of breathing may be far from existing standards, and an unintentional reduction in respiratory volume may lead to hypoxia of the brain, which will result in poor patient prognosis.

Intubation or Alternative?

Ventilation with a facemask in a two-person team may prove ineffective despite proper positioning and seal. Ventilation using a facemask by one rescuer is difficult; maintaining proper tightness may be impossible and involve leaks. Further obstacles may include facial hair, lack of dentition, and nonstandard shape of the face. Good practice should include the use of an alternative airway for ventilation. However, the most effective method of ventilation is endotracheal intubation.

Compression Platform

An ideal solution, especially in a two-person team, is the use of a platform for mechanical chest compressions. Before the platform is connected, we use a witness who can perform basic resuscitation procedures, in particular a properly performed indirect massage of the heart. This protects the patient and makes the witness feel part of the rescue mission, which will encourage him/her to intervene again in the future.

Monitoring

During CPR performed by a two-person team, the use of multifunction electrodes guarantees the safety and good quality of the rhythm reading on the monitor. Additionally it is possible to compress the chest during defibrillator charging according to ERC guidelines. Connecting multifunction electrodes and four limb electrodes allows for proper assessment of myocardial function and lets us quickly respond to heart problems.

After return of spontaneous circulation, a 12-lead ECG should be performed, remembering the correct placement of the electrodes. For the precordial electrodes, V1 goes at the right fourth intercostal space at the sternum margin; V2 at the left fourth intercostal space at the sternal margin; V3 midway between V2 and V4; V4 at the left fifth intercostal space around mid-clavicle; V5 at the left fifth intercostal space and anterior axillary line; and V6 at the left fifth intercostal and midaxillary line. In the event of a sudden cardiac arrest during the 12-lead ECG, attach the electrodes under the right collarbone and left shoulder blade (anterior-posterior electrode placement).

A Practical Note

Simultaneous use of the platform for mechanical chest compressions and a transport respirator will cause conflict. The devices are not synchronized with each other, so breaths may not be delivered in the right time and volume. It is possible to use a respirator for CPR but remember to enable the CPR function for manual chest compressions. 
 
Conclusion

Using two-person teams to conduct cardiac arrest resuscitations shows us how important teamwork is in addition to knowledge of treatment algorithms. Optimal teamwork can be achieved through continuous exercises and proper use of equipment.

In the case of sudden cardiac arrest, time is of the utmost importance, and victim survival will largely depend on whether there were witnesses. By promptly compressing the chest we can improve perfusion and thus oxygenate the brain and most important organs. The witness is the most important rescuer in sudden cardiac arrest. 

Specialized equipment can improve the quality of CPR. Cyclical trainings are the best way to improve the quality of activities at SCA scenes and additionally allow for a quick transition to automatism. 

For medical emergency teams, knowledge and the ability to implement algorithms and procedures are the keys to success, and equipment should be well known and always ready to use. 

Robert Rajtar is a medical rescuer with 14 years of experience in hospital emergency departments and with EMS teams in Poland and Germany. He works at the provincial emergency service station in Szczecin. 

Zbigniew Pankowski is a medical rescuer at the provincial rescue service station in Szczecin. He has been a healthcare worker since 1987 in the admission room of Poviat Hospital as well as an emergency care unit and medical dispatcher’s office.