Tag Archives: BLS

The Sichuan Straddle

I used to see it done on ‘ER’ but never knew people really straddled patients on stretchers doing CPR. Apparently they do in Sichuan, China and have now produced a manikin study to demonstrate its effectiveness. It might work there, but I imagine there are frequent situations in Australia (where I work) in which the combined weight of patient and paramedic would present an unfair load to the stretcher.

OBJECTIVE: To evaluate the efficacy of straddling external chest compression performed on moving stretchers.

METHODS: The study was a prospective, randomized, cross-over study on a manikin performed at a university hospital. Twenty subjects were selected from the 40 graduates using random numbers to participate in the study. Participants were randomized to either performing standard or straddling external chest compression followed by the other technique 7 days later. The compression variables and time to first compression were recorded.

RESULTS: Twenty subjects (12 males and 8 females) took part in the study. There were no differences between the standard and straddling external chest compression for the compression rate, effective compression percentage and compression depth. There was no difference between the standard external chest compression and straddling external chest compression for incorrect hand position and incomplete release compression. Time to first compression during straddling external chest compression (10.31 ± 1.65 s) was greater than that during standard external chest compression (2.74 ± 0.40 s) (P < 0.001).

CONCLUSIONS: The quality of straddling external chest compression performed on a moving stretcher was as effective as standard external chest compression performed on the floor. By performing straddling external chest compression, time for transporting victims to the emergency department to get advanced life support may be shortened.

The efficacy of straddling external chest compression on a moving stretcher
Resuscitation. 2010 Nov;81(11):1562

CPR on your own? Stay at the head end

In this manikin study, single-rescuer bag-mask ventilation (BMV) with chest compressions was tried in three different positions. Staying at the head end to deliver effective BMV, with ‘over-the-head’ chest compressions from that position, was best.

Background The 2005 guidelines for cardiopulmonary resuscitation (CPR) do not include a statement on performance of basic life support by a single healthcare professional using a bagevalveemask device. Three positions are possible: chest compressions and ventilations from over the head of the casualty (over-the-head CPR), from the side of the casualty (lateral CPR), and chest compressions from the side and ventilations from over the head of the casualty (alternating CPR). The aim of this study was to compare CPR quality of these three positions.

Methods 102 healthcare professionals were randomised to a crossover design and performed a 2-min CPR test on a manikin for each position.

Results The hands-off time over a 2-min interval was not significantly different between over-the-head (median 31 s) and lateral (31 s) CPR, but these compared favourably with alternating CPR (36 s). Over-the-head CPR resulted in significantly more chest compressions (155) compared with lateral (152) and alternating CPR (149); the number of correct chest compressions did not differ significantly (119 vs 122 vs 109). Alternating CPR resulted in significantly less inflations (eight) compared with over-the-head (ten) and lateral CPR (ten). Lateral CPR led to significantly less correct inflations (three) compared with over-the-head (five) and alternating CPR (four).

Conclusions In the case of a single healthcare professional using a bagevalveemask device, the quality of over-the-head CPR is at least equivalent to lateral, and superior to alternating CPR. Because of the potential difficulties in bagevalveemask ventilation in the lateral position, the authors recommend over-the-head CPR.

Comparison of the over-the-head, lateral and alternating positions during cardiopulmonary resuscitation performed by a single rescuer with a bag valve mask device
Emerg Med J. 2010 Oct 14. [Epub ahead of print]

Better outcomes with conventional CPR

A very large nationwide Japanese observational study examined outcomes in out-of-hospital cardiac arrest patients who received CPR from lay rescuers. They compared conventional CPR (with mouth-to-mouth and chest compressions) with compression-only CPR. Over 40 000 patients were included.

Conventional CPR was associated with better outcomes than chest compression only CPR, for both one month survival (adjusted odds ratio 1.17, 95% confidence interval 1.06 to 1.29) and neurologically favourable one month survival (1.17, 1.01 to 1.35). Neurologically favourable one month survival decreased with increasing age and with delays of up to 10 minutes in starting CPR for both conventional and chest compression only CPR. The benefit of conventional CPR over chest compression only CPR was significantly greater in younger people in non-cardiac cases (P=0.025) and with a delay in start of CPR after the event was witnessed in non-cardiac cases (P=0.015) and all cases combined (P=0.037).

The authors conclude that conventional CPR is associated with better outcomes than chest compression only CPR for selected patients with out of hospital cardiopulmonary arrest, such as those with arrests of non-cardiac origin and younger people, and people in whom there was delay in the start of CPR.

Outcomes of chest compression only CPR versus conventional CPR conducted by lay people in patients with out of hospital cardiopulmonary arrest witnessed by bystanders: nationwide population based observational study
BMJ 2011; 2011; 342:c7106 Full Text

Improved survival with modified CPR

A large randomised controlled trial1 on out-of-hospital cardiac arrest patients compared standard CPR with CPR augmented by two modifications:

  • active compression-decompression using a hand-held suction device to compress the chest. The device is attached to the chest of the patient during CPR and the rescuer actively lifts the chest upwards after each compression, which are done at a rate of 80/min
  • augmented negative intrathoracic pressure using an impedance threshold device, which is a valve that limits passive air entry into the lungs during chest compressions, thereby reducing intrathoracic pressure and increasing blood flow to vital organs

The primary study endpoint was survival to hospital discharge with favourable neurological function.

Funding issues resulted in premature cessation of the study. 47 (6%) of 813 controls survived to hospital discharge with favourable neurological function compared with 75 (9%) of 840 patients in the intervention group (odds ratio 1·58, 95% CI 1·07–2·36; p=0·019]. 74 (9%) of 840 patients survived to 1 year in the intervention group compared with 48 (6%) of 813 controls (p=0·03), with equivalent cognitive skills, disability ratings, and emotional-psychological statuses in both groups. The overall major adverse event rate did not differ between groups, but more patients had pulmonary oedema in the intervention group (94 [11%] of 840) than did controls (62 [7%] of 813; p=0·015).

An accompanying editorial2 points out that previous studies in animal models of cardiac arrest gave reassuring results for both devices individually and when used together, but results from clinical trials in patients have been mixed for each device when used individually:

  • For compression-decompression CPR, a systematic review pooled the existing data for such CPR versus standard CPR in 4162 patients and found no difference in short-term mortality (relative risk 0·98, 95% CI 0·94–1·03) or survival to hospital discharge (0·99, 0·98–1·01). The 2010 CPR guidelines for the USA and Europe do not recommend the use of compression–decompression CPR alone.
  • The most current systematic review for the impedance-threshold device showed a significantly improved early survival (relative risk 1·45, 1·16–1·80), and a short-term improved neurological outcome (2·35, 1·30–4·24); however, improved long- term survival did not reach conventional statistical significance (1·48, 0·91–2·41).

The Resuscitation Outcomes Consortium (ROC) PRIMED study3 showed no survival benefit in 8718 patients randomised to standard CPR with an active or sham impedance-threshold device (the Consortium includes the same investigators as the Lancet paper). This was published as an abstract in Circulation recently.

The editorialist has reservations regarding a change in clinical practice resulting from this new study, partly because the trial was stopped prematurely and enrolment of a larger cohort could have changed the findings, and partly because the open use of both devices might have unintentionally introduced bias into the study. Further validation is recommended.

1. Standard cardiopulmonary resuscitation versus active compression-decompression cardiopulmonary resuscitation with augmentation of negative intrathoracic pressure for out-of-hospital cardiac arrest: a randomised trial
Lancet 2011;377:301-11

2. Augmented CPR: rescue after the ResQ trial
Lancet. 2011 Jan 22;377:276-7

3. The Resuscitation Outcomes Consortium ROC) PRIMED Impedance Threshold Device (ITD) Cardiac Arrest Trial: A Prospective, Randomized, Double-Blind, Controlled Clinical Trial
Circulation 2010; 122: 2215–26 (abstr)

Body position in poisoning

You come across a patient in the community who has taken an overdose of pills. The ambulance is on its way and you have no medical equipment. Is there any first aid that might help? How should you position the patient if they are unconscious?

Authors of a BestBet in the EMJ searched the literature to answer the three-part question:
In [orally poisoned patients] does [a specific body position] result in [a better outcome for the patient]?

The limited evidence they found from just two papers suggests that drug absorption is lowest in patients lying on their left side, so you might want to consider placing an unconscious overdose patient in the left-sided recovery position prior to definitively managing them in hospital. The theoretical increased risk of pulmonary aspiration on the left side should be considered however. The table shows just how limited this evidence base is – but the idea is an interesting one.

Optimal body position in oral poisoning cases
Emerg Med J 2010;27:952-953 Full text from the BestBets site

CAB rather than ABC

The 2010 ILCOR resuscitation guidelines were published today. Key changes and continued points of emphasis from the 2005 BLS Guidelines include the following:

  • Sequence change to chest compressions before rescue breaths (CAB rather than ABC)
  • Immediate recognition of sudden cardiac arrest based on assessing unresponsiveness and absence of normal breathing (ie, the victim is not breathing or only gasping)
  • “Look, Listen, and Feel” removed from the BLS algorithm
  • Encouraging Hands-Only (chest compression only) CPR (ie, continuous chest compression over the middle of the chest) for the untrained lay-rescuer
  • Health care providers continue effective chest compressions/CPR until return of spontaneous circulation (ROSC) or termination of resuscitative efforts
  • Increased focus on methods to ensure that high-quality CPR (compressions of adequate rate and depth, allowing full chest recoil between compressions, minimizing interruptions in chest compressions and avoiding excessive ventilation) is performed
  • Continued de-emphasis on pulse check for health care providers
  • A simplified adult BLS algorithm is introduced with the revised traditional algorithm
  • Recommendation of a simultaneous, choreographed approach for chest compressions, airway management, rescue breathing, rhythm detection, and shocks (if appropriate) by an integrated team of highly-trained rescuers in appropriate settings

2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Part 5: Adult Basic Life Support
Circulation. 2010;122:S685-S705

Compression-only CPR vs standard CPR

Two studies comparing compression-only CPR with conventional CPR:

BACKGROUND: The role of rescue breathing in cardiopulmonary resuscitation (CPR) performed by a layperson is uncertain. We hypothesized that the dispatcher instructions to bystanders to provide chest compression alone would result in improved survival as compared with instructions to provide chest compression plus rescue breathing.

METHODS: We conducted a multicenter, randomized trial of dispatcher instructions to bystanders for performing CPR. The patients were persons 18 years of age or older with out-of-hospital cardiac arrest for whom dispatchers initiated CPR instruction to bystanders. Patients were randomly assigned to receive chest compression alone or chest compression plus rescue breathing. The primary outcome was survival to hospital discharge. Secondary outcomes included a favorable neurologic outcome at discharge.

RESULTS: Of the 1941 patients who met the inclusion criteria, 981 were randomly assigned to receive chest compression alone and 960 to receive chest compression plus rescue breathing. We observed no significant difference between the two groups in the proportion of patients who survived to hospital discharge (12.5% with chest compression alone and 11.0% with chest compression plus rescue breathing, P=0.31) or in the proportion who survived with a favorable neurologic outcome in the two sites that assessed this secondary outcome (14.4% and 11.5%, respectively; P=0.13). Prespecified subgroup analyses showed a trend toward a higher proportion of patients surviving to hospital discharge with chest compression alone as compared with chest compression plus rescue breathing for patients with a cardiac cause of arrest (15.5% vs. 12.3%, P=0.09) and for those with shockable rhythms (31.9% vs. 25.7%, P=0.09).

CONCLUSIONS: Dispatcher instruction consisting of chest compression alone did not increase the survival rate overall, although there was a trend toward better outcomes in key clinical subgroups. The results support a strategy for CPR performed by laypersons that emphasizes chest compression and minimizes the role of rescue breathing. (Funded in part by the Laerdal Foundation for Acute Medicine and the Medic One Foundation; ClinicalTrials.gov number, NCT00219687.)

CPR with chest compression alone or with rescue breathing
N Engl J Med. 2010 Jul 29;363(5):423-3

BACKGROUND: Emergency medical dispatchers give instructions on how to perform cardiopulmonary resuscitation (CPR) over the telephone to callers requesting help for a patient with suspected cardiac arrest, before the arrival of emergency medical services (EMS) personnel. A previous study indicated that instructions to perform CPR consisting of only chest compression result in a treatment efficacy that is similar or even superior to that associated with instructions given to perform standard CPR, which consists of both compression and ventilation. That study, however, was not powered to assess a possible difference in survival. The aim of this prospective, randomized study was to evaluate the possible superiority of compression-only CPR over standard CPR with respect to survival.

METHODS: Patients with suspected, witnessed, out-of-hospital cardiac arrest were randomly assigned to undergo either compression-only CPR or standard CPR. The primary end point was 30-day survival.

RESULTS: Data for the primary analysis were collected from February 2005 through January 2009 for a total of 1276 patients. Of these, 620 patients had been assigned to receive compression-only CPR and 656 patients had been assigned to receive standard CPR. The rate of 30-day survival was similar in the two groups: 8.7% (54 of 620 patients) in the group receiving compression-only CPR and 7.0% (46 of 656 patients) in the group receiving standard CPR (absolute difference for compression-only vs. standard CPR, 1.7 percentage points; 95% confidence interval, -1.2 to 4.6; P=0.29).

CONCLUSIONS: This prospective, randomized study showed no significant difference with respect to survival at 30 days between instructions given by an emergency medical dispatcher, before the arrival of EMS personnel, for compression-only CPR and instructions for standard CPR in patients with suspected, witnessed, out-of-hospital cardiac arrest. (Funded by the Swedish Heart–Lung Foundation and others; Karolinska Clinical Trial Registration number, CT20080012.)

Compression-Only CPR or Standard CPR in Out-of-Hospital Cardiac Arrest
N Engl J Med. 2010 Jul 29;363(5):434-42

Infant CPR: two thumbs even when alone

Infant CPR guidelines recommend two-finger chest compressions with a lone rescuer and two-thumb with two rescuers. Two-thumb provides better chest compression but is perceived to be associated with increased ventilation hands-off time. A manikin study revealed more effective compressions with the two-thumb technique with only four fewer compressions per minute compared with two-fingers.

Two-thumb technique is superior to two-finger technique during lone rescuer infant manikin CPR
Resuscitation. 2010 Jun;81(6):712-7

Best position for CPR

A study using volunteer doctors and nurses in simulated cardiac arrest resuscitations compared three different positions for delivering CPR: standing, kneeling by the patient, or standing on a “taboret”. They measured rescuer fatigue and effectiveness of CPR. They conclude that CPR is best performed in a kneeling position in that it maximizes duration of effective chest compression and minimizes back pain. The authors recommend if two or more experienced healthcare providers are available to perform CPR, alternating rescuers every 2 min in the kneeling or standing on a taboret positions, and every 1min in the standing on the floor position in order to minimize rescuer fatigue.

Rescuer fatigue and cardiopulmonary resuscitation positions: A randomized controlled crossover trial
Resuscitation. 2010 May;81(5):579-84