Reprinted from the September 2004 issue of RESPIRATORY CARE [Respir Care 2004;49(9):1085–1099]
RAD 1.0 PROCEDURE:
Recognition of signs suggesting the possibility or the presence of cardiopulmonary arrest, initiation of resuscitation, and therapeutic use of defibrillation in adults.
RAD 2.0 DESCRIPTION/DEFINITION:
Resuscitation in the health care setting for the purpose of this guideline encompasses all care necessary to deal with sudden and often lifethreatening events affecting the cardiopulmonary system, and involves the identification, assessment, and treatment of patients in danger of or in frank arrest, including the high-risk delivery patient. This includes (1) alerting the resuscitation team and the managing physician; (2) using adjunctive equipment and special techniques for establishing, maintaining, and monitoring effective ventilation and circulation; (3) monitoring the electrocardiograph and recognizing dysrhythmias; (4) using defibrillators [This includes the use of conventional defibrillators and automated (automatic or semi-automatic) external defibrillators (AEDs).] and mechanical ventilators; (5) administering oxygen and drugs, including instillation of drugs via the endotracheal tube; and (6) stabilizing such patients in the post-arrest period.
RAD 3.0 SETTING:
This guideline applies to a variety of settings including but not limited to hospitals, long-term facilities, outpatient clinics, rehabilitation centers, skilled nursing facilities, and pre- and interhospital transport.
RAD 4.0 INDICATIONS:
Cardiac arrest, respiratory arrest, or the presence of conditions that may lead to cardiopulmonary arrest as indicated by rapid deterioration in vital signs, level of consciousness, and blood gas values —included in those conditions are
4.1 Airway obstruction—partial or complete
4.2 Acute myocardial infarction with cardiodynamic instability
4.3 Life-threatening dysrhythmias
4.4 Hypovolemic shock
4.5 Severe infections
4.6 Spinal cord or head injury
4.7 Drug overdose
4.8 Pulmonary edema
4.10 Pulmonary embolus
4.11 Smoke inhalation
4.12 Defibrillation is indicated when cardiac arrest results in or is due to ventricular fibrillation. 1-5
4.13 Pulseless ventricular tachycardia
RAD 5.0 CONTRAINDICATIONS:
Resuscitation is contraindicated when
5.1 The patient’s desire not to be resuscitated has been clearly expressed and documented in the patient’s medical record6-9
5.2 Resuscitation has been determined to be futile because of the patient’s underlying condition or disease9-18
5.3 Defibrillation is also contraindicated when immediate danger to the rescuers is present due to the environment, patient’s location, or patient’s condition.
RAD 6.0 PRECAUTIONS/HAZARDS AND/OR COMPLICATIONS:
The following represent possible hazards or
complications related to the major facets of resuscitation:
6.1 Airway management10,11
6.1.1 Failure to establish a patent airway19- 21
6.1.2 Failure to intubate the trachea19,20
6.1.3 Failure to recognize intubation of the esophagus19,22,23
6.1.4 Upper airway trauma, laryngeal and esophageal damage24-29
22.214.171.124 Vocal cord paralysis28
6.1.6 Cervical spine trauma24,31,32
6.1.7 Unrecognized bronchial intubation19,30,33
6.1.8 Eye injury21
6.1.9 Facial trauma30
6.1.10 Problems with ETT cuff21,34-36
6.1.13 Dental accidents24,30
6.1.15 Hypotension and bradycardia due to vagal stimulation37
6.1.16 Hypertension and tachycardia37,39
6.1.17 Inappropriate tube size30,34,40
6.2.1 Inadequate oxygen delivery (FDO2)42-45
6.2.2 Hypo- and/or hyperventilation43-47
6.2.3 Gastric insufflation and/or rupture45,48,49
6.2.5 Hypotension due to reduced venous return secondary to high mean intrathoracic pressure52,53
6.2.6 Vomiting and aspiration21,54
6.2.7 Prolonged interruption of ventilation for intubation55
6.3.1 Ineffective chest compression56,57
6.3.2 Fractured ribs and/or sternum24,54,58,59
6.3.3 Laceration of spleen or liver24,54,58,60-62
6.3.4 Failure to restore circulation despite functional rhythm
126.96.36.199 Severe hypovolemia63,64
188.8.131.52 Cardiac tamponade58,64
184.108.40.206 Hemo- or pneumothorax63,64
220.127.116.11 Massive acute myocardial infarction63
18.104.22.168 Aortic dissection63
22.214.171.124 Cardiac rupture59,65
126.96.36.199 Air embolus, pulmonary embolism58,66
6.3.5 Central nervous system impairment58
6.4 Electrical therapy
6.4.1 AEDs may be hazardous in patients weighing < 25 kg67
6.4.2 Failure of defibrillator68
6.4.3 Shock to team members69
6.4.4 Pulse checking between sequential shocks of AEDs delays rapid identification of persistent ventricular fibrillation, interferes with assessment capabilities of the devices, and increases the possibility of operator error.67
6.4.5 The initial 3 shocks should be delivered in sequence, without delay, interruption for CPR, medication administration, or pulse checks for ventricular fibrillation and pulseless ventricular tachycardia.2,4,70-72
6.4.6 Induction of malignant dysrhythmias73,74
6.4.7 Interference with implanted pacemaker function75-77
6.4.8 Fire hazard
188.8.131.52 AEDs may be hazardous in an oxygen-enriched environment.78
184.108.40.206 Alcohol should never be used as conducting material for paddles because serious burns can result.79
220.127.116.11 Superficial arcing of the current along the chest wall can occur as a consequence of the presence of conductive paste or gel between the paddles.80
18.104.22.168 The aluminized backing on some transdermal systems can cause electric arcing during defibrillation, with explosive noises, smoke, visible arcing, patient burns, and impaired transmission of current;81-84 therefore, patches should be removed before defibrillation.
6.4.9 Muscle burn81,85
6.4.10 Muscle injury resulting in acute renal failure86,87
6.4.11 If transthoracic impedance is high, a low energy shock (< 100 J) may fail to generate enough current to achieve successful defibrillation.88-91
6.4.12 Attention must be paid to factors influencing total and transthoracic impedance.67,79,88,90,91
22.214.171.124 Paddle electrode pressure
126.96.36.199 The use of an appropriate conductive medium that can withstand high current flow
188.8.131.52 Electrode/paddle size— should be 8.5 to 12 cm for adults
184.108.40.206 Electrode placement
220.127.116.11 Time interval between shocks
18.104.22.168 Distance between electrodes (size of the chest)
22.214.171.124 Energy selected
126.96.36.199 Paddle-skin electrode material
188.8.131.52 Number of previous shocks
184.108.40.206 Phase of ventilation
220.127.116.11 Diaphoretic patients should be dried to prevent contact problems with adhesive defibrillation pads and/or electrodes.
6.5 Drug administration
6.5.1 Inappropriate drug or dose
6.5.2 Idiosyncratic or allergic response to drug
6.5.3 Endotracheal-tube drug-delivery failure91-94—The endotracheal tube dose should be 2 to 2.5 times the normal I.V. dose, diluted in 10 mL of normal saline (or distilled water).
RAD 7.0 LIMITATIONS OF PROCEDURE:
7.1 Despite adequate efforts, resuscitation may fail because of the patient’s underlying disease. Institution of resuscitation may be limited by patient or surrogate/guardian request. 6-9
7.2 Additional limitations to defibrillation
7.2.1 Response is poor in subjects with extremely low core temperatures, and shocks should be limited to 3 until temperature has risen above 86°F (30°C).91 Warming may improve success.91
7.2.2 Subjects whose cardiac arrest occurs as a direct result of trauma may not respond to defibrillation.91
7.2.3 The patient must not move or be moved while analysis is occurring when the automated or semi-automated defibrillator is used. (Compressions must be stopped, and the patient should not be moving.)
RAD 8.0 ASSESSMENT OF NEED:
8.1 Assessment of patient condition
8.1.1 Pre-arrest—Identification of patients in danger of imminent arrest and in whom consequent early intervention may prevent arrest and improve outcome. These are patients with conditions that may lead to cardiopulmonary arrest as indicated by rapid deterioration in vital signs, level of consciousness, and blood gas values (see Section 4.00).
8.1.2 Arrest—absence of spontaneous breathing and/or circulation
8.1.3 Post-arrest—Once a patient has sustained an arrest, the likelihood of additional life-threatening problems is high, and continued vigilance and aggressive action using this Guideline are indicated. Control of the airway and cardiac monitoring must be continued and optimal oxygenation and ventilation assured.
18.104.22.168 After arrival of defibrillator: The patient should be evaluated immediately for the presence of ventricular fibrillation or ventricular tachycardia by the operator (conventional) or the defibrillator (automated or semi-automated). Inappropriate defibrillation can cause harm.
RAD 9.0 ASSESSMENT OF PROCESS AND OUTCOME:
9.1 Timely, high-quality resuscitation im- proves patient outcome in terms of survival and level of function. Despite optimal resuscitation performance, outcomes are affected by patient-specific factors. Patient condition post-arrest should be evaluated from this perspective.
9.2 Documentation and evaluation of the resuscitation process (eg, system activation, team member performance, functioning of equipment, and adherence to guidelines and algorithms) should occur continuously and improvements be made91,95-99
9.3 Equipment management issues. Use of standard checklists can improve defibrillator dependability.100
9.4 Defibrillation process issues
9.4.2 Response time91,102,103
9.4.3 First-responder actions91,102-104
9.4.4 Adherence to established algorithms105
9.4.5 Patient selection and outcome
9.4.6 First responder authorization to defibrillate91,103,106
RAD 10.0 RESOURCES:
10.1 Emergency response system—A designated resuscitation team should be continuously available (24 hours/day,7 days/week) to respond to emergencies.99 Specialty resuscitation teams trained to meet the needs of different hospital populations are desirable (eg, trauma, stroke). Team members should be notified simultaneously. All hospital workers must know how to activate the hospital’s emergency response system.
10.2 Equipment should be rapidly available and functional. Durability, portability, reliability, and cost should be considered.
10.2.1 Ventilation devices
10.2.1.1 Mouth-to-mask devices must
10.2.1.1.1 Provide a way to increase FDO2 91,103,107-114
10.2.1.1.2 Separate inhaled and exhaled gas91,103,107-114
10.2.1.1.3 Incorporate an effective filter (one-way valve or bacteria filter)107-114
10.2.1.1.4 Be transparent107-114
10.2.1.1.5 Easily achieve an airtight seal107-114
10.2.1.1.6 Have extension tube to facilitate visual monitoring and ventilation107-114
10.2.1.1.7 Have dead space as low as practical107-114
10.2.1.2 Manual resuscitators must
10.2.1.2.1 Be capable of providing an FDO2 of 1.0 even when large volumes are delivered42,91,115-118
10.2.1.2.2 Have no pressure-relief valve for adults91
10.2.1.2.3 Have a bag volume of approximately 1,600 mL for adults91,103
10.2.1.2.4 Have minimal forward and back leak42,118
10.2.1.2.5 Have standard 15- and 22-mm fitting91,118,119
10.2.1.2.6 Be impossible to misassemble
10.2.1.2.7 Be easily sterilized or for single-patient use
10.2.1.2.8 Provide for measurement of exhaled tidal volume95,96
10.2.1.2.9 Provide some indication that supplemental oxygen is being supplied (easily ascertained with bag reservoir but difficult with tube-type reservoir)
10.2.1.2.10 Be capable of being restored to proper function after being disabled with vomitus42,120,121
10.2.1.2.11 Be able to be restored to proper function after being dropped from a height of 1 meter onto concrete floor
10.2.1.2.12 Be designed so that pressure generated at the patient connection port is < 5 cm H2O during exhalation (at a flow of 5 L/min for patients weighing < 10 kg and 50 L/min for all others) 122,123
10.2.1.2.13 Be designed so that pressure generated at the patient connection port does not exceed - 5 cm H2O during inspiration (at a flow of 5 L/ min for patients weighing < 10 kg and 50 L/min for all others)122,123
10.2.1.2.14 Be capable of providing a high FDO2 during spontaneous breathing with low inspiratory and expiratory resistance (see above)122,123
10.2.1.3 Face-mask design should allow a tight seal, provide minimal internal dead space, and have a clear mask body. A variety of sizes should be available.108-110,124
10.2.1.4 Non-self-inflating bags vary in size from 500-2,000 mL, are inflated by a controlled gas source, have variable flow outlets, and conform to the same standards listed in 10.2.1.2 (where appropriate).
10.2.1.5 Gas-powered resuscitators (manually triggered, commonly called demand valves) are not recommended. 42,116,125-130
10.2.1.6 Transport ventilators are recommended for resuscitation if they provide control over tidal volume, inspiratory time, and inspiratory flow, and deliver FDO2 of 1.0.131,132
10.2.1.7 The continued use of the mechanical ventilator is indicated when a patient already being mechanically ventilated is resuscitated if the ventilator provides control over tidal volume, inspiratory time, and flow; can be manually triggered; and delivers an FDO2 of l .0.
10.2.2 Circulation devices
10.2.2.1 Manually operated mechanical chest compressors are appropriate for adults and may be advantageous during transport.91,133-135 They must be capable of providing an adjustable stroke of 1.5 to 2 in (3.9 to 5.0 cm), deliver the compression for 50% of the compression-relaxation cycle, and should be placed in use with only brief interruption of manual CPR. The compressor head should be designed to limit shift in position and stroke adjustment and should have a locking mechanism. The device must be portable, stored easily, and assembled quickly.
10.2.2.2 Automatic mechanical chest compressors are appropriate for adults and should have the capabilities of the manual devices plus the advantage of delivering optimal rate and depth of compression by eliminating the variables of operator technique and fatigue. The device should allow electrocardiogram (ECG) recording, and defibrillation should not require that the device be stopped or removed.91 It is not recommended that these devices be used for ventilation unless a cuffed endotracheal tube is in place.
10.2.3 Airway management devices
10.2.3.1 Oropharyngeal airways should be available in a variety of sizes for adults. Design should incorporate a flange, a short bite-block segment, and a curved body containing a channel for air movement and suctioning.
10.2.3.2 Nasopharyngeal airways should be available in a variety of sizes for adults. They consist of a soft rubber or plastic tube with a beveled tip and a flange that preferably is adjustable.
10.2.3.3 Endotracheal tubes should be available in a variety of sizes for adults. Tubes should meet ASTM standards.136
10.2.3.4 Intubation devices facilitate intubation and access to the difficult airway. Such devices may include laryngoscope and blades (straight & curved), wire guide/stylet, forceps, fiberoptic laryngoscope or bronchoscope, “light wand,” or tube changing stent.
10.2.3.5 Tube stabilization should be reliable and effective and allow for atraumatic extubation and reintubation when necessary.
10.2.3.6 Suctioning devices should be capable of subatmospheric pressure levels of > –120 cm H2O for pharyngeal suctioning and between –80 and –120 cm H2O for tracheobronchial suctioning in adults.91 A portable system should be available for transport. A variety of rigid pharyngeal tips and a variety of sizes of sterile tracheal catheters should be available. The tracheal suction catheter selected should have an outside diameter of < 1/2 the inside diameter of the endotracheal (or tracheostomy) tube and have a means of manual control (thumb port).
10.2.4 Electrical therapy devices
10.2.4.1.1 Monophasic or biphasic defibrillator waveforms
10.2.4.1.1.1 With monophasic devices the current is delivered in one direction. The recommended first energy shock is 200 J, the second is 200 or 300 J, and the third is 360 J. This escalating energy level is used to find the lowest level that terminates ventricular fibrillation while minimizing injury from the shock.67
10.2.4.1.1.2 With biphasic devices the current is delivered in 2 phases. In one phase it is delivered in a positive direction, and in the second it is delivered in the negative direction. Low energy (≤ 200 J) from biphasic devices can terminate ventricular fibrillation safely with as much or more efficacy compared to escalating energy from monophasic devices. 67
10.2.4.1.1.3 Since randomized prospective studies comparing these devices are lacking, the committee cannot recommend one type of defibrillator over the other.
10.2.4.1.2 Manual defibrillators depend upon operator for analysis of rhythm, charging, proper application of paddles to patient’s thorax, and delivery of countershock; use of self-adhesive pads may increase efficacy and speed of countershock. 137,138 Using self-adhesive pads will also prevent the application of the wrong contact gel during defibrillation.
10.2.4.1.3 Semiautomatic/automatic defibrillators utilize large, self-adhesive pads to optimize electrical contact with the patient’s thorax and allow delivery of countershock more rapidly than manual defibrillators.68,138 Automatic defibrillators, when attached to patient, analyze rhythm and deliver countershock when appropriate without intervention by operator; semiautomatic defibrillators require pressing a button to initiate rhythm analysis and advise operator when delivery of countershock (by pressing a button) is appropriate.139-142
10.2.4.1.4 External pacemakers allow noninvasive cardiac pacing via large, self-adhesive pads, in cases of bradycardia with a pulse or high-grade block when a conducted beat results in a pulse.142- 145
10.2.5 Monitoring devices
10.2.5.1 ECG monitors—Continuous electrocardiographic monitoring is essential for detection of dysrhythmias and for directing therapy.
10.2.5.2 CO2 monitors—CO2 detectors are useful for identification of correct endotracheal tube placement and for monitoring of cardiac function during resuscitation.146-150
10.2.5.3 Ventilation monitors—Because artificial ventilation, either manual or mechanical, is often inconsistent during resuscitation, monitoring of exhaled volume is recommended. 95,96
10.2.5.4 Pulse oximeters—Pulse oximeters, if used in the pre- and post-arrest situation, may provide useful information regarding oxygenation and cardiovascular performance. Those that display pulse waveform are preferred.
10.2.5.5 Invasive hemodynamic monitoring devices—Continuous monitoring of intravascular waveforms and pressures provides useful information for diagnosis and treatment of cardiovascular compromise.
10.2.5.6 Airway pressure monitoring is useful in adults.
10.3 Personnel: A high percentage of patients in nontraumatic cardiac arrest are in ventricular fibrillation within the first few minutes after their collapse. As time after arrest increases, the likelihood of a successful outcome decreases rapidly.91,106,151 Early defibrillation as a standard has been expanded to include the use of AEDs by first responders trained in basic life support (BLS), for both prehospital and in-hospital cardiac arrest due to ventricular fibrillation. All health care providers must recognize the need for and know how to activate the facility’s emergency response system. They should be trained, evaluated at frequent intervals by monitoring performance, and retrained as necessary in the skills of BLS. Health care providers who are primary members of resuscitation teams in acute care hospitals should be skilled in emergency cardiac care (ECC) and advanced cardiac life support (ACLS).152-156
10.3.1 Level I152-156
10.3.1.1 Training—all Level I personnel should be trained, evaluated by performance, and retrained as necessary in BLS and the use of AED at frequent intervals that do not exceed 2 years. Retraining should focus on identified deficiencies.
10.3.1.2 Responsibilities—Level I: All health care providers who have direct patient care responsibilities and may be the first responder to patients in cardiac arrest are considered Level I caregivers. No special professional credential is necessary to qualify as Level I, by this definition. Designated first responders must be able to recognize that the patient is unresponsive, apneic, and pulseless. They should be able to attach automated defibrillator electrodes, operate AEDs, and complete an AED checklist at least every shift.157 Level I personnel also assist the primary (Level II) members of the resuscitation team. They should be capable of assisting Level II personnel by (l) assessing patients for respiratory and/or cardiac arrest, (2) activating the resuscitation team, (3) administering BLS, (4) providing mouth-tomask ventilation, (5) attaching ECG and automatic defibrillator electrodes, (6) assisting with tracheal intubation, (7) defibrillating with automatic electronic defibrillators, (8) attaching pulse oximeter and capnograph, (9) preparing a written record of resuscitation effort, (10) moving resuscitation equipment to the scene, and (11) collecting arterial blood for analysis.
10.3.1.3 Credentials—Level I health care providers should have a current BLS health care provider course completion card from the American Heart Association. Hospital personnel should at a minimum be capable of assessing the patient for respiratory and/or cardiac arrest, activating the resuscitation team, and administering BLS until the team arrives.
10.3.2 Level II152
10.3.2.1 Training—Level II personnel should be trained, evaluated by performance, and retrained as necessary in ECC and ACLS as appropriate at intervals that should not exceed 2 years. Retraining should focus on identified deficiencies.
10.3.2.2 Responsibilities—Level II health professionals should be capable of serving as primary members of the resuscitation team and as team leader when they are the best qualified respondent. They may respond not only to resuscitation calls in their work areas but also to other areas of the hospital. They are skilled in the use of all adjunctive equipment and special techniques for ECC/ACLS (eg, establishing, maintaining, and monitoring effective ventilation and circulation). They have the skills of Level I personnel and the following capabilities: (1) advanced ECG monitoring and dysrhythmia recognition, (2) tracheal intubation, (3) capability to deliver shocks with automated and conventional external defibrillators, (4) use of continuous and transport mechanical ventilators, (5) use of manual or automatic external chest compressors, (6) preparation and administration of cardiac drugs, (7) stabilization of patients in the post-arrest period, (8) provision of access for rapid administration of intravenous fluids, (9) managing ventilation via transtracheal catheter and cricothyrotomy, (10) emergency treatment of tension pneumo- or hemothorax with large bore needle, (11) interpretation of hemodynamic data (12) preparing patients for emergency transport, and (13) evaluating oxygenation, ventilation and acid-base balance from blood gas reports.
10.3.2.3 Credentials—Level II health professionals should have a current BLS and ACLS certification from the American Heart Association.
RAD 11.0 MONITORING:
11.1.1 Clinical assessment—continuous observation of the patient and repeated clinical assessment by a trained observer provide optimal monitoring of the resuscitation process. Special consideration should be given to the following:
22.214.171.124 Level of consciousness
126.96.36.199 Adequacy of airway
188.8.131.52 Adequacy of ventilation
184.108.40.206 Peripheral/apical pulse and character
220.127.116.11 Evidence of chest and head trauma
18.104.22.168 Pulmonary compliance and airway resistance
22.214.171.124 Presence of seizure activity
11.1.2 Assessment of physiologic parameters —Repeat assessment of physiologic data by trained professionals supplements clinical assessment in managing patients throughout the resuscitation process. Monitoring devices should be available, accessible, functional, and periodically evaluated for function. These data include but are not limited to95
126.96.36.199 Arterial blood gas studies (although investigators have suggested that such values may have a limited role in decision-making during CPR158
188.8.131.52 Hemodynamic data152,158-160
6 184.108.40.206 Cardiac rhythm153,154
220.127.116.11 Ventilatory frequency, tidal volume, and airway pressure95,96
18.104.22.168 Exhaled CO2 146-150
22.214.171.124 Neurologic status
11.2 Resuscitation process—properly performed resuscitation should improve patient outcome. Continuous monitoring of the process will identify areas needing improvement. Among these areas are response time, equipment function, equipment availability, team member performance, team performance, complication rate, and patient survival and functional status.
11.3 Equipment—All maintenance should be documented and records preserved. Included in documentation should be routine checks
of energy output, condition of batteries, proper functioning of monitor and recorder, and presence of disposables needed for function of defibrillator, including electrodes and defibrillation pads. Defibrillators should be checked and documented each shift for presence, condition, and function of cables and paddles; presence of defibrillating and monitoring electrodes, paper, and spare batteries (as applicable); and charging, message/light indicators, monitors, and ECG recorder (as applicable).91 AEDs should be checked and documented each day for function and appropriate maintenance.67
11.4 Training—Records should be kept of initial training and continuing education of all personnel who perform defibrillation as part of their professional activities.
RAD 12.0 FREQUENCY/AVAILABILITY/ DURATION:
12.1 Because the need for resuscitation occurs unpredictably, resources need to be available to respond to one or more locations simultaneously 24 hours a day, 7 days a week. BLS response should be immediate, and ACLS should be available as soon as feasible based upon the resources of the institution. Resuscitation continues until vital signs are restored. If vital signs are not restored, resuscitation efforts should continue until a physician decides further efforts are futile.
12.2 Personnel who respond to cardiac arrests should be trained to operate, equipped with, and permitted to operate a defibrillator. 67 No other therapeutic intervention, including setting up oxygen delivery systems, suction equipment, advanced airway procedures, intravenous lines, or mechanical CPR devices, should take precedence over or be routinely performed when a defibrillator is available and defibrillation is indicated.67
RAD 13.0 INFECTION CONTROL:
13.1 Implement Standard Precautions,161 including mouth-to-barrier devices.
13.2 Observe all infection control guidelines posted for patient.
13.3 Disinfect all equipment to be reused on other patients.
Revised by David Vines MHS RRT, University of Texas Health Science Center, San Antonio, Texas, and approved by the 2003 CPG Steering Committee
This Clinical Practice Guideline combines 2 earlier guidelines, Defibrillation During Resuscitation [Respir Care 1995;40(7):744-748] and Resuscitation in Acute Care Hospitals [Respir Care 1993;38(11):1179-1188]
Interested persons may copy these Guidelines for noncommercial purposes of scientific or educational advancement. Please credit AARC and Respiratory Care Journal.
Reprinted from the September 2004 issue of RESPIRATORY CARE [Respir Care 2004;49(9):1085–1099]