This is the fourth and final column in my series on sudden cardiac arrest (SCA). If you would like to start at the beginning of the story, here are the links to Parts I, II, and III. In addition to reviewing the pertinent science, this series also recounts the story of my father’s survival of a SCA in April of 2012.
At the end of Part III, my father’s heart had just been restarted after 20 minutes of CPR and four shocks from an Automated External Defibrillator (AED) and he was being transported via ambulance to State College Area Hospital. Although Dad’s heart was beating on its own at this point, he was still unconscious. During the brief transport from the squash court to the hospital, the EMTs began packing my father’s body in ice, the first step in a protocol called therapeutic hypothermia.
As discussed in earlier segments of this series, a big risk for survivors of SCA is brain damage. This damage occurs via two primary mechanisms. The first comes from a cascade of events caused by lack of oxygen. Back in high school biology you learned about cellular metabolism (trust me, you did) and the importance of a molecule called adenosine triphosphate (ATP). Among its several functions, ATP maintains the proper balance of salts within a cell. When deprived of oxygen, a cell can no longer produce ATP, and therefore cannot maintain the proper balance of salts. The resulting salt imbalance can kill the cell.
The second mechanism of possible injury occurs from pressure within the skull resulting from the rapid return of blood flow from the restarted heart. This pressure increase is augmented by inflammation stemming from the immune system’s response to all of the unexpected activity in the brain. When the combined pressure from these two factors reaches a sufficient level, brain cell death can result.
Both of the mechanisms of injury listed above can be ameliorated by lowering the victim’s body temperature. As your body temperature drops, so does the permeability of the walls of your cells. This hinders the diffusion of salts either into or out of cells, thereby preserving the pre-SCA salt concentrations during the time when your brain cannot produce ATP. Cooling the victim also lowers the pressure within the skull by reducing inflammation, in the same way that an ice pack reduces swelling from a sprained ankle.
Shortly after my father arrived at the hospital in State College, a decision was made to transport him via helicopter to Geisinger Medical Center in Danville, PA.(1) Upon arrival, Dad was fitted with cooling jackets that covered his torso and his thighs and which were set to maintain his core body temperature at 92ºF. In addition, Dad was given Propofol to keep him sedated, and a paralytic drug to keep him from shivering. The use of the paralytic meant that Dad needed a ventilator to breathe.
I arrived at Geisinger around midnight, 10 hours after Dad’s collapse on the squash court. I want to share several observations from the hospital which I think could be helpful if you are ever visiting a loved one undergoing therapeutic hypothermia. Due to his reduced body temperature, Dad’s skin was extremely pale and extraordinarily cold to the touch. His chest was badly bruised from the broken ribs that he received during CPR. It was a rather difficult site to behold, but as we will discuss, not necessarily an indicator of a poor medical outcome.
After keeping Dad at 92ºF for 24 hours, it was time to warm him up by slowly raising the set-points on the cooling jackets. After six hours, Dad’s body temperature was back up to 98.6°F and normal color was returning to his skin. The doctor came in to stop the flow of the sedative and paralytic into his IV, and told us to expect Dad to wake up in approximately 30 minutes. Dad was apparently impatient and woke up almost immediately, which we were informed was a very good sign.
This point in the recovery process represented an important but also difficult transition for the support team – me, my sister and my mother. Our focus was no longer on Dad’s survival, which seemed assured at this point, but rather the preservation of his cognitive function. Again, I want to share some observations with you that may be of some comfort if you are the caregiver in this situation someday. You should expect that the patient will be extremely disoriented at this point. Just imagine the situation from Dad’s point of view. One minute he was playing squash, and the next minute he was in a hospital bed with a tube down his throat surrounded by his wife, son, and daughter, all with concerned looks on their faces. Furthermore, he had spent over 24 hours on Propofol, a drug which causes significant mental confusion.
There is one particular moment from the hospital that I will never forget. Dad still had the ventilator tube in his mouth and was trying to ask questions. It was hard to understand what he was saying. I held his hand, and when he would ask me something I would repeat back what I thought the question was. If I was correct he would squeeze my hand. Over the next several hours he asked me, “What happened?” and “Where am I?” at least 20 times each. To which I would answer, “you collapsed on the squash court” and “in the hospital.” Eventually it occurred to him to ask what hospital he was in. When I told him he was at Geisinger Medical Center, the place you are taken in central Pennsylvania when the situation is serious, he was clearly scared. I was at once both profoundly saddened to have frightened him and overjoyed that he knew to be frightened, which I interpreted as a sign that his mind was working just fine.
Now that Dad had survived the SCA and neurological issues were no longer a concern, it was time to prepare for the future. On the 5th day after “The Incident,” Dad had a pacemaker/defibrillator installed in his chest. The pacemaker has wires which connect to all four chambers of his heart, ensuring they all contract at the proper rhythm. The defibrillator portion of the device monitors his heart and stands at the ready to shock it back into the proper rhythm if he ever experiences another arrhythmia. Statistics have shown that this device provides excellent protection in the event of another such occurrence. Fortunately, Dad has not had any further incidents. After a day of recovery, including some slow walks around the cardiac ward, we hopped in the car and drove home to State College. It was only seven days after he arrived at Geisinger. He has had no residual effects from the incident and has returned to the squash courts.
Dad’s story represents the best possible outcome of a sudden cardiac arrest, and I think it is important to review the factors which contributed to this. In chronological order, these are:
1. Dad was in good physical condition;
2. Dad’s squash partner called for help immediately;
3. The two women who responded were certified in CPR and began to perform it immediately;
4. Recreation Hall at Penn State has AEDs that were available and well marked;
5. Penn State Campus Police and the EMTs from State College Area Hospital responded quickly to the 911 call;
6. The EMTs began therapeutic hypothermia immediately;
7. The Emergency Room Staff at State College Area Hospital knew to transport Dad to Geisinger rather than attempt to treat him on site;
8. The helicopter was available and staffed with personnel with the appropriate expertise;
9. Geisinger Medical Center has the expertise and equipment to treat SCA vicitims.
No single factor alone was responsible for my father’s survival and recovery. My family and I are sincerely grateful to all who participated in this remarkable outcome.
I hope you found this series on Sudden Cardiac Arrest to be informative. If you have comments or questions use the interface below to send me an email at firstname.lastname@example.org.
(1) For those of you not familiar with Geisinger Medical Center, it is a nationally known medical center in central PA which handles many of the difficult medical cases outside of either Philadelphia or Pittsburgh.
(2) OK, I know there really isn’t a second footnote above. Nevertheless I could not finish this series without thanking my friend Scott Balderson, who was available to me 24/7 with sound counsel and unwavering support throughout that very difficult and unusual week. So many thanks from your buddy from church.