Page 264 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

168 PART 2: General Management of the Patient

In the in-hospital setting, where sudden ventricular fibrillation/ventricular is deemed unresponsive, the initial observer should immediately call for
tachycardia (VF/VT) from coronary events is not the most common help while assessing the patient and providing initial care, following the
mechanism of arrest, prevention requires a different approach. Several new format of CAB (see above).
studies have demonstrated that hospitalized patients who suffer cardiac
arrest frequently exhibit signs and symptoms of destabilization up to ■ CIRCULATION
12 hours before they become pulseless. 20,21 These symptoms include vital The hemodynamic status of the patient should be assessed via palpation
sign changes such as progressive hypotension, tachycardia, hypothermia, of arterial sites. As an approximate guide, the radial, femoral, and carotid
or hypoxia. They also include clinical changes such as mental status dete- pulses are lost at systolic pressures below 80, 70, and 60 mm Hg, respec-
rioration or progressive shortness of breath. Therefore, nursing staff should tively. Therefore, the most sensitive site to assess is the carotid artery.
15
be appropriately vigilant in monitoring for such changes, and physicians If no pulse can be felt at the carotid, chest compressions should be
should be duly attentive to warning signs from patients and staff. Early initiated immediately. Compressions should be performed at a rate of at
stabilization by such measures as intubation, initiation of vasopressor least 100 beats per minute and to a depth of at least 2 in.
therapy, and/or transfer to an intensive care unit are far more effective than Recent studies have demonstrated the importance of “good quality”
treating cardiac arrest once it has occurred. In an effort to prevent cardiac chest compressions, partially defined by compressions performed at
arrest, rapid response teams have been implemented, which include health the appropriate rate and depth. This is important in light of the fact
care providers who are trained to recognize and treat the early signs of that studies have shown performance of chest compressions to be
destabilization that may lead to cardiac arrest. This concept was formalized grossly suboptimal and highly variable in actual practice. 29-30 Rescuers
in Europe and Australia and is now being used in the United States with should pay particular attention to the performance of this skill. Newer
increasing frequency in diverse hospital environments. 22-24 generations of monitor/defibrillators, currently available but not widely
implemented, may aid this process by monitoring the quality of chest
RESUSCITATION TEAM ORGANIZATION compressions and generating alarms during suboptimal performance.
It is very important for hospitals, ICUs, and prehospital care systems to Intriguing recent data have suggested that chest compressions may be
establish a clearly delineated team structure for cardiac arrest treatment. more important than defibrillation in the initial treatment of cardiac
In-hospital studies have shown that a well-trained and organized arrest arrest. 31,32 These observations, which might have been considered
team is an important component in the resuscitation from sudden death. heretical just several years ago, lend support to an important paradigm
25
Team members should be ACLS trained and have a specified team leader in cardiac arrest, that of the three-phase model of cardiac arrest (see
33
who will lead the resuscitation efforts. Training should emphasize the discussion later in this chapter). Other methods to improve CPR
need for a hierarchical structure, with the team leader making most treat- performance have also been shown effective, including performing
ment decisions, to prevent the confusion that often occurs during cardiac a series of uninterrupted chest compressions followed by one shock
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arrest events. It also should be emphasized that response time is critical, continued with another series of uninterrupted chest compressions.
such that a resuscitation team should be able to arrive on the scene of a This push for continuous chest compressions stresses the need to cir-
cardiac arrest within minutes to initiate treatment. Recent data demon- culate the oxygenated blood throughout the body during cardiac arrest
strate that groups with best-practice survival from cardiac arrest have resuscitation efforts.
mean “call to shock” times (for VF/VT arrest) of 5 minutes or less, and Monitoring the adequacy of the circulation during performance
26
certainly the earlier the response, the more likely a better outcome will be of CPR traditionally has been based on palpation of pulses, which is
obtained. Resuscitation efforts during cardiac arrest require activities to now generally considered to be highly unreliable. Capnography is an
be performed quickly, calmly, and in regimented fashion. Rescuer panic attractive adjunct to bedside clinical monitoring because the amount
and disorganized efforts are counterproductive and can best be avoided by of carbon dioxide returned from peripheral tissues and then exhaled
appropriate training before (and debriefing after) events take place. With from the lungs should be a measure of the adequacy of cardiac output.
34a
the growth of medical simulation technology and sophisticated manikins In one prospective, observational study, 150 consecutive out-of-
for resuscitation training, it is possible for cardiac arrest teams to rehearse hospital cardiac arrests were monitored by end-tidal carbon dioxide
scenarios to supplement education and enhance preparedness. 27,28 levels after intubation. After 20 minutes of advanced cardiac life
support, end-tidal carbon dioxide levels averaged 4.4 ± 2.9 mm Hg
BASIC LIFE SUPPORT in nonsurvivors and 32.8 ± 7.4 mm Hg in survivors (p < 0.001).
A 20-minute end-tidal carbon dioxide value of 10 mm Hg or less suc-
The first steps of resuscitation from cardiac arrest involve what is known cessfully discriminated between 115 nonsurvivors and the 35 patients
as basic life support (BLS). These fundamental skills are part of CPR train- who survived to hospital admission. While not yet routine, capnog-
ing courses offered to the public by organizations such as the American raphy may be useful for both judging the adequacy of resuscitative
Heart Association and the American Red Cross. Given the importance efforts and offering prognostic information. The American Heart
of early recognition and care for cardiac arrest, it is incumbent on all Association 2010 Guidelines recommend using capnography during
medical personnel from ward receptionists to radiology technicians to resuscitation. 35
physicians to maintain BLS training. Health care workers also should While not strictly part of BLS, fluid resuscitation is a crucial adjunct
encourage the public to obtain these skills, which are often summarized to circulatory support in the initial phases of resuscitation, especially
by the ABCs—airway, breathing, and circulation. With the release of during arrest with pulseless electrical activity as an initial rhythm.
the 2010 international consensus resuscitation guidelines (published in Intravenous access should be obtained rapidly if it is not already
the United States through the American Heart Association), increased present, and adult patients should receive a rapid infusion of at least
emphasis has now been placed on circulating oxygenated blood during 500 to 1000 mL of 0.9% saline or lactated Ringer’s solution. In children,
out-of-hospital cardiac arrest resuscitation efforts and de-emphasizing the crystalloid infusion should be calculated at 20 mL/kg. The ideal
airway evaluation and ventilation—now summarized by CAB instead of IV access would include a peripheral large-bore (ie, 14-18 gauge)
ABC—circulation, airway, and breathing. 15 catheter, intraosseus line, and/or large-bore central catheter (ie, not a
double- or triple-lumen catheter). If a central-line approach is chosen
INITIAL ASSESSMENT as opposed to a peripheral IV, the optimal site for central-line place-
ment in resuscitation is the femoral vein. Since the chest and neck
The assessment of “Look, Listen, and Feel” has been removed from are active sites for chest compressions and ventilatory support, respec-
guidelines recommendations pertaining to the initial assessment and tively, subclavian or internal jugular approaches are impractical unless
emphasis has been placed on immediate chest compressions. If a patient already present.

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