Slowly but surely, the word isgetting out. A cardiac collapse victimcan be sustained with effort for a surprising length of time. The best I have seen so far is three hours inLondon
Accepted wisdom has been that thebrain begins to die within several minutes of the heart stopping. This led to an early cessation of effort andthe certain death of the victim. Now weknow that strong cardio will keep the brain alive (and all the other organs aswell) for as much as three hours.
Strong cardio is hard work andone would need to be spelled in order to maintain the effort. Here it is suggested that the compression bea full two inches to produce the necessary effects. That may be just playing safe. However, when I suffered a cardiac arrest, myfriend who is a strong body builder, would certainly have maintained a strongcardio compression stroke and did that until the paramedics arrived. In my case, I went a full twenty minuteswithout a heartbeat. I obviously had afull recovery.
It is curious that I had myattack in my friend’s apartment within ten blocks of the city’s premier cardiocare facility and he had taken training in Nursing and CPR in particular. I could not have planned it better had I tried. It certainly demonstrated that survival wasvery possible and since then eyes have been opened to the prospect of victim survival.
This work now provides us withthe necessary tools to determine if the body is still exchanging oxygen and justifyingheroic efforts to recover the victim.
96 Minutes Without a Heartbeat
New Strategies to Revive Victims of Cardiac Arrest; Improving Odds ofSurvival Without Brain Damage
By RONWINSLOW
A little-known device is shaking conventional wisdom for revivingpeople who suffer sudden cardiac arrest: People may be able to go much longerwithout a pulse than the 20 minutes previously believed.
The capnograph, which measures carbon dioxide being expelled from themouth of the patient, can tell rescuers when further efforts at cardiopulmonaryresuscitation, or CPR, are futile or whether they should be continued. It isthe latest effort that cardiology experts and emergency teams are devising thataim to improve a patient's odds.
The American Heart Association recently revised its guidelines forfirst responders, with particular emphasis on initiating hard, rapid chestcompressions to keep the stricken victim's blood circulating. Rescue squadsincreasingly are chilling victims of cardiac arrest with ice packs and othercooling approaches, a technique known as hypothermia, in order to protect thebrain from injury when blood flow is restored.
Some 300,000 Americans suffer sudden cardiac arrest each year, andfewer than 10% survive long enough to leave the hospital.
For Howard Snitzer, a 54-year-old chef from Goodhue , Minn.
Mr. Snitzer's rescuers, who rotated every couple of minutes to avoidfatigue, kept pumping his chest. Thirty-four minutes after he went down, amedical team from the Mayo Clinic swooped in via helicopter. During the ordeal,11 shocks with a defibrillator failed to restore his heartbeat.
What kept them going? Readings
"If we didn't have the CO2 readings we were getting, we would haveterminated efforts much sooner," says Bruce Goodman, a flight paramedicwith the Mayo Clinic's Medical Transport unit, which was summoned to Mr.Snitzer's aid.
Sudden cardiac arrest typically results from a heart attack or anelectrical malfunction that causes a runaway heartbeat. Mr. Snitzer went intoventricular fibrillation, a quivering of the heart that leaves it without apulse.
Of the 300,000 annual cases of sudden cardiac arrest outside ahospital, 125,000 victims are found too late to be helped, says Michael Sayre,associate professor of emergency medicine at Ohio State University, Columbus,and co-author of the American Heart Association's new CPR guidelines. A personwho is down for 10 to 12 minutes without any assistance is almost impossible torevive. For the others a critical factor in their prospects is whether someonesaw them collapse, called 911 and began effective CPR.
After cardiac arrest, separate actions may beneeded to revive a patient.
· Chestcompressions (left), at a rate of at least 100 per minute and two inches deep,are needed to keep the blood circulating.
· Electric shockwith an automated external defibrillator may help restore the heart's rhythm
· A breathingtube inserted into the windpipe allows rescuers to pump air into the lungs andto detect whether CO2 is being exhaled, a sign that oxygen-rich blood iscirculating through the body
The big worry in sudden cardiac arrest beyond restarting the heart isprotecting the brain. Other organs such as the kidneys and the lungs "cantolerate longer periods" without oxygen, but the brain is the organ thatsuccumbs most likely early on," says Roger White, a Mayo Clinicanesthesiologist who was involved in Mr. Snitzer's case and who is an expert inmanagement of sudden cardiac arrest.
Rescuers have long monitored patients' breathing tubes for carbon dioxideto make sure the device was correctly placed in the windpipe instead of theesophagus. Now for the first time, the recent AHA guidelines, which werepublished last fall, call for a more sophisticated and continuous monitoring ofCO2. Just last week, the AHA published course materials to teach emergencypersonnel how to use capnography.
The technology records CO2 pressure in millimeters of mercury. Researchby Dr. White and others shows that if the maximum CO2 pressure achieved during20 minutes of CPR is 14 or less, resuscitation is almost certainly futile. Ifthe level is above about 25, "you need to keep working at it until you'veexhausted all of your tricks," Dr. White said.
When Mr. Goodman and his co-workers hooked Mr. Snitzer up to thecapnograph upon their arrival, they were impressed with his CO2: It was in thelow 30s. A normal level in healthy adults is between 35 and 45. But after theeffort went on for 45 minutes, Mr. Goodman became concerned. In his 15-yearcareer as a paramedic, the longest successful CPR case he'd been on was about45 minutes.
Mr. Goodman consulted by cellphone four times with Dr. White. Afterabout an hour and 15 minutes had elapsed following Mr. Snitzer's collapse, thetwo decided that an additional dose of an anti-arrhythmia drug and one moreshock—the 12th—would be the last chance. CPR continued as those steps weretaken. At the 96th minute, soon after the shock was administered, Mr. Snitzer'spulse returned.
Mr. Goodman wasn't inclined to celebrate. "I'll be honest, it wasnot a great feeling that night," he recalls. "It was a good feelingthat we got pulses back, but there was nothing in history to tell me he wouldsurvive this and that he could recover" with his brain intact. "Iwasn't sure we had done the right thing for him."
About five days later, Mr. Goodman learned that Mr. Snitzer, who hadbeen treated for a heart blockage, kidney failure and other problems, was outof intensive care. Mr. Goodman and other colleagues who worked on the case wentto the hospital to visit. Mr. Snitzer was sitting up in a conference room,talking to his family in a normal voice. "It was a little bit of a shellshock to see him doing that well," Mr. Goodman says.
In a report on the case published online last month by Mayo ClinicProceedings, Dr. White and his colleagues reported that Mr. Snitzer"experienced a complete neurologic recovery" and described theepisode as the "longest duration of pulselessness in an out-of-hospitalcardiac arrest with a good outcome."
Mr. Snitzer goes regularly to the Mayo Clinic for cardiacrehabilitation. He says he had hardly any idea what happened to him or how hecame to survive it. But as he learned about the quick response from rescueworkers and how the signals from the capnograph convinced them not to quit, hesaid: "I'm a regular guy. I happened to die at the right place at theright time."
Corrections & Amplifications
A device called a capnograph that can be used in rescuing victims ofsudden cardiac arrest measures levels of carbon dioxide in millimeters ofmercury. An early version of this story incorrectly said it was in milligramsof mercury.
Write to Ron Winslow at ron.winslow@wsj.com
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