Dispatcher Recognition of cardiac arrest
Author(s): Christian Vaillancourt, Manya Charette, Mike Smyth
Date: 06 November 2014
Question: Among adults and children who are in cardiac arrest outside of a hospital (P), does the description of any specific symptoms to the dispatcher (I), compared with
the absence of any specific description (C), change increase the likelihood of cardiac arrest recognition (O)?
Settings: Out of hospital
Bibliography:
Studies added since 2010








Deakin, C; Evans, S; King, P. Evaluation of telephone-cardiopulmonary resuscitation advice for paediatric cardiac arrest. Resuscitation 2010; 81 (7): 853-6.
Clawson, J; Barron, T; Scott, G; Siriwardena, N; Patterson, B; Olola, C. Medical Priority Dispatch System breathing problems protocol key question combinations are
associated with patient acuity. Prehosp Disaster Med 2012; 27 (4): 375-80.
Tanaka, Y; Taniguchi, J; Wato, Y; Yoshida, Y; Inaba, H. The continuous quality improvement project for telephone-assisted instruction of cardiopulmonary resuscitation
increased the incidence of bystander CPR and improved the outcomes of out-of-hospital cardiac arrests. Resuscitation 2012; 83 (10): 1235-41.
Lewis, M; Stubbs, B; Eisenberg, M. Dispatcher-assisted cardiopulmonary resuscitation: time to identify cardiac arrest and deliver chest compression instructions.
Circulation 2013; 128 (14): 1522-30.
Weiser, C; van Tulder, R; Stöckl, M; Schober, A; Herkner, H; Chwojka, C; Hopfgartner, A; Novosad, H; Schreiber, W; Sterz, F; Dispatchers impression plus Medical Priority
Dispatch System reduced dispatch centre times in cases of out of hospital cardiac arrest. Pre-alert--a prospective, cluster randomized trial. Resuscitation 2013; 84 (7):
883-8.
Stipulante, S; Tubes, R; Fassi, M; Donneau, A; Van Troyen, B; Hartstein, G; D'Orio, V; Ghuysen, Al. Implementation of the ALERT algorithm, a new dispatcher-assisted
telephone cardiopulmonary resuscitation protocol, in non-Advanced Medical Priority Dispatch System (AMPDS) Emergency Medical Services centres. Resuscitation 2014;
85 (2):177-81.
Dami, F; Fuchs, V; Praz, L; Vader, J. Introducing systematic dispatcher-assisted cardiopulmonary resuscitation (telephone-CPR) in a non-Advanced Medical Priority
Dispatch System (AMPDS): implementation process and costs. Resuscitation 2010; 81 (7): 848-52.
Bång, A; Herlitz, J; Martinell, S. Interaction between emergency medical dispatcher and caller in suspected out-of-hospital cardiac arrest calls with focus on agonal
breathing. A review of 100 tape recordings of true cardiac arrest cases. Resuscitation 2003; 56 (1): 25-34.



















2010 studies included:
Bohm, K; Stålhandske, B; Rosenqvist, M; Ulfvarson, J; Hollenberg, J; Svensson, L. Tuition of emergency medical dispatchers in the recognition of agonal respiration
increases the use of telephone assisted CPR. Resuscitation 2009; 80 (9): 1025-8.
Clawson, J; Olola, C; Scott, G; Heward, A; Patterson, B. Effect of a Medical Priority Dispatch System key question addition in the seizure/convulsion/fitting protocol to
improve recognition of ineffective (agonal) breathing. Resuscitation 2008; 79 (2): 257-64.
Eisenberg, M; Hallstrom, A; Carter, W; Cummins, R; Bergner, L; Pierce, J. Emergency CPR instruction via telephone. Am J Public Health 1985; 75 (1): 47-50.
Heward, A; Damiani, M; Hartley-Sharpe, C. Does the use of the Advanced Medical Priority Dispatch System affect cardiac arrest detection? Emerg Med J 2004; 21 (1):
115-8.
Roppolo, L; Westfall, A; Pepe, P; Nobel, L; Cowan, J; Kay, J; Idris, A. Dispatcher assessments for agonal breathing improve detection of cardiac arrest. Resuscitation 2009;
80 (7): 769-772.
Vaillancourt, C; Verma, A; Trickett, J; Crete, D; Beaudoin, T; Nesbitt, L; Wells, G; Stiell, I. Evaluating the effectiveness of dispatch-assisted cardiopulmonary resuscitation
instructions. Acad Emerg Med 2007; 14 (10): 877-83.
Bång, A; Biber, B; Isaksson, L; Lindqvist, J; Herlitz, J. Evaluation of dispatcher-assisted cardiopulmonary resuscitation. Eur J Emerg Med 1999; 6 (3): 175-83.
Bohm, K; Rosenqvist, M; Hollenberg, J; Biber, B; Engerström, L; Svensson, L. Dispatcher-assisted telephone-guided cardiopulmonary resuscitation: an underused lifesaving
system. Eur J Emerg Med 2007; 14 (5): 256-9.
Cairns, K J; Hamilton, A J; Marshall, A H; Moore, M J; Adgey, A A J; Kee, F. The obstacles to maximising the impact of public access defibrillation: an assessment of the
dispatch mechanism for out-of-hospital cardiac arrest. Heart 2008; 94 (3): 349-53.
Castrén, M; Kuisma, M; Serlachius, J; Skrifvars, M. Do health care professionals report sudden cardiac arrest better than laymen? Resuscitation 2001; 51 (3): 265-8.
Clark, J; Culley, L; Eisenberg, M; Henwood, D. Accuracy of determining cardiac arrest by emergency medical dispatchers. Ann Emerg Med 1994; 23 (5): 1022-6.
Hallstrom, A; Cobb, L; Johnson, E; Copass, M. Dispatcher assisted CPR: Implementation and potential benefit. A 12-year study. Resuscitation 2003; 57 (2): 123-129.
Hauff, S; Rea, T; Culley, L; Kerry, F; Becker, L; Eisenberg, M. Factors Impeding Dispatcher-Assisted Telephone Cardiopulmonary Resuscitation. Ann Emerg Med 2003; 42
(6): 731-737.
Nurmi, J; Pettilä, V; Biber, B; Kuisma, M; Komulainen, R; Castrén, M. Effect of protocol compliance to cardiac arrest identification by emergency medical dispatchers.
Resuscitation 2006; 70 (3): 463-9.
Flynn, J; Archer, F; Morgans, A. Sensitivity and specificity of the medical priority dispatch system in detecting cardiac arrest emergency calls in Melbourne. Prehosp
Disaster Med 2006; 21 (2): 72-6.
Garza, A; Gratton, M;Chen, J; Carlson, B. The accuracy of predicting cardiac arrest by emergency medical services dispatchers: The calling party effect. Acad Emerg Med
2003; 10 (9): 955-960.
Kuisma, M; Boyd, J; Väyrynen, T; Repo, J; Nousila-Wiik, M; Holmström, P. Emergency call processing and survival from out-of-hospital ventricular fibrillation. Resuscitation
2005; 67 (1): 89-93.
Ma, M; Lu, T; Ng, J; Lin, C; Chiang, W; Ko, P; Shih, F; Huang, C; Hsiung, K; Chen, S; Chen, W. Evaluation of emergency medical dispatch in out-of-hospital cardiac arrest in
Taipei. Resuscitation 2007; 73 (2): 236-45.
Berdowski, J; Beekhuis, F; Zwinderman, A; Tijssen, J; Koster, R. Importance of the first link: description and recognition of an out-of-hospital cardiac arrest in an emergency
call. Circulation 2009; 119 (15): 2096-102.
2010 studies excluded:




Eisenberg, M; Carter, W; Hallstrom, A; Cummins, R; Litwin, P; Hearne, T. Identification of cardiac arrest by emergency dispatchers. Am J Emerg Med 1986; 4 (4): 299301. [contains very little of use regarding identification of cardiac arrest beyond reporting that if patient is over 50 and caller is emotional then there is a higher probability
of cardiac arrest]
Bobrow, B; Zuercher, M; Ewy, G; Clark, L; Chikani, V; Donahue, D; Sanders, A; Hilwig, R; Berg, R; Kern, K. Gasping during cardiac arrest in humans is frequent and associated
with improved survival. Circulation 2008; 118 (24): 2550-4. [paper addresses incidence of gasping, does not address identification of cardiac arrest]
Clawson, J; Olola, C; Heward, A; Patterson, B; Scott, G. Profile of emergency medical dispatch calls for breathing problems within the medical priority dispatch system
protocol. Prehosp Disaster Med 2008; 23 (5): 412-9. [paper addresses call prioritisation of breathing problems, does not seek to identify cardiac arrest only to determine
if high dispatch priority was assigned]
Clawson, J; Olola C; Heward, A; Patterson, B. Cardiac arrest predictability in seizure patients based on emergency medical dispatcher identification of previous seizure or
epilepsy history. Resuscitation 2007; 75: 298-304. [paper addresses whether querying callers about prior history of seizure can help predict cardiac arrest, but does not
report on cardiac arrest recognition]
Quality assessment
№ of patients
Impact
№ of
studies
Study design
Risk of
bias
Inconsistency
Indirectness
not serious
very
serious 1
Imprecision
Other
considerations
intervention
control
none
103/256
pre-alerts
98/262
pre-alerts
Quality
Importance
⨁◯◯◯
VERY
LOW
CRITICAL
⨁◯◯◯
VERY
LOW
CRITICAL
⨁◯◯◯
VERY
LOW
CRITICAL
⨁◯◯◯
VERY
LOW
CRITICAL
Dispatcher recognition of cardiac arrest
1
3
Randomised
trial (cluster)
Before-After
(observational
studies)
5
Before-after
(observational
studies)
9
Prospective
(observational
studies)
not
serious
serious
not serious
serious
very
serious
6
not
serious
not serious
serious
not serious
very
serious
very
serious
2
not
serious
3
3
serious
very
serious
none
4
7
none
none
After
Before
2312/3108
(74.4%)
1780/3000
(59.3%)
After
Before
512/8275
(61.9%)
296/5885
(50.3%)
4,357
Weiser (2013) Compared “gut feeling”: MPDS code not actual patient status.
Gut feeling correct 40% (pre-alert days) and 37% (non-pre-alert days). Words
"dead" & "is dead" seemed to help dispatchers recognize CA more quickly.
Relative Risk: 1.08 (95% CI, 0.87 to 1.33)
Absolute Difference: 2.8% (95% CI, -5.5% to 11.1%)
Three studies investigated the impact of additional education for dispatchers:
Bohm (2009) education on agonal breathing; increase in provision of T-CPR
from 47% to 68%; T-CPR with agonal breathing present 23% before training
vs. 56% after; Relative Risk: 1.44 (95% CI, 1.09 to 1.91); Absolute Difference:
21.1% (95% CI, 5.4% to 35.4%)
Roppolo (2009) education on agonal breathing; missed cases decreased from
28% to 18.8% following education; agonal breathing described as slow, barely
breathing, noisy, gurgling, gasping; timing of breathing allowed dispatchers to
identify additional cases; Relative Risk: 1.13 (95% CI, 1.05 to 1.21); Absolute
Difference: 9.26% (95% CI, 3.72% to 14.51%)
Tanaka (2012) education on agonal breathing, emesis and seizure; cases
where T-CPR not attempted decreased following education 44% v. 26%, as
did preventable factors where T-CPR not offered 25% v. 12%; Relative Risk:
1.30 (95% CI, 1.25 to 1.36); Absolute Difference: 17.16% (95% CI, 14.53 to
19.76)
Five studies investigated the impact of scripted protocols, or additions to
scripted protocols:
Heward (2004) recognition increased from 15 to 50% (actual numbers not
reported)
Eisenberg (1985) Bystander CPR: 45% (before) v. 56%; Relative Risk: 4.32
(95% CI, 2.67 to 6.98); Absolute Difference: 29.53% (95% CI, 21.98% to
36.45%)
Vaillancourt (2007); sensitivity: 56.3%; agonal respiration accounted for 50%
of non-identified CA (after) (no data on recognition in before group)
Clawson (2008); new question added to seizure protocol; 53% high acuity to
77%; increased provision of T-CPR; Relative Risk: 1.47 (95% CI, 1.16 to 1.84);
Absolute Difference: 24.65% (95% CI, 10.65% to 37.51%)
Stipulante (2014); recognition decreased from 81.5% to 74.8%; rates of T-CPR
increased; Relative Risk: 1.09 (95% CI, 1.00 to 1.19); Absolute Difference:
6.63% (-0.02% to 13.14%)
Focus of questioning on consciousness (is patient awake, can they be
awakened) and breathing pattern (is patient breathing, breathing normally,
listen to breathing over phone, count breaths).Recognition was reported in a
variety of ways. We have attempted to group by outcome below.
Quality assessment
№ of patients
Impact
№ of
studies
Study design
Risk of
bias
Inconsistency
Indirectness
Imprecision
Other
considerations
intervention
Quality
Importance
⨁◯◯◯
VERY
LOW
CRITICAL
control
Sensitivity: Sensitivity was reported in one study as 68.9% (Cairns, 2008).
Cardiac Arrest Recognition: Recognition was reported or could be calculated
in six studies (Bohm, 2007; Bång, 2003; Dami, 2010; Hallstrom, 2003; Nurmi,
2006; Castrén, 2001) and ranged from 18% (Bång, 2003) to 83% (Nurmi,
2006).
Noteworthy:
1. Presence of agonal breathing was reported as a potential issue in cardiac
arrest recognition in four studies (Bohm, 2007; Bång, 2003; Dami, 2010;
Nurmi, 2006). Bohm (2007) reported that CPR was offered to 23% with signs
of breathing vs. 92% described as not breathing. Only 4/38 patients with
abnormal breathing were offered T-CPR in Bång (2003). Dami (2010)
reported 21 cases of unrecognized OHCA where the bystander reported
normal breathing. In the Nurmi (2006) paper, the identification rate was 80%
when there was abnormal breathing vs. 83% overall.
2. There is evidence from two studies (Dami, 2010; Hallstrom 2003) to
indicate that cardiac arrest recognition decreases when the protocol is not
followed. Dami (2010) reported 60 unrecognized cases (20.4%) because
protocol questions about consciousness and breathing were not asked.
Hallstrom (2003) reported protocol deviations in 69% of unrecognized cases
vs. 5.3% of recognized cases.
3. Bång (2003) reported an incidence of agonal breathing of ~30% and noted
the following descriptors: difficulty, poorly, gasping, wheezing, impaired,
occasional breathing.
Cardiac arrest recognition was reported heterogeneously across the studies.
We have grouped the studies below by the outcome used.
8
Retrospective
(observational
studies)
very
serious 6
not serious
very
serious 3
very
serious 7
none
3,417
Sensitivity: Sensitivity was reported in four studies (Deakin, 2010; Flynn,
2006; Garza, 2003; Ma, 2007) and ranged from 68.3% (Garza, 2003) to 96.9%
(Ma, 2007).
Specificity: Specificity was reported in two studies and exceeded 99% in both
(Deakin, 2010; Flynn, 2006).
Cardiac Arrest Recognition: Cardiac arrest recognition was reported or could
be calculated in three studies (Deakin, 2010; Lewis, 2013; Kuisma, 2005) and
ranged from 45.2% (Deakin, 2010) to 80% (Lewis, 2013).
Noteworthy:
The presence of agonal breathing was reported to decrease cardiac arrest
recognition in two studies (Lewis, 2013; Hauff, 2003).
Lewis (2012) reported recognition of cardiac arrest increases if a dispatcher is
able to assess consciousness and breathing.
Quality assessment
№ of
studies
Study design
Case control
(observational
study)
1
1.
2.
3.
4.
5.
6.
7.
8.
9.
Risk of
bias
serious 8
Inconsistency
not serious
№ of patients
Indirectness
not
serious
Imprecision
very
serious 9
Other
considerations
none
intervention
Impact
Quality
Importance
Berdowski (2009) EMDs to ask about consciousness and breathing.
Recognition: 71.2%; sensitivity: 71% (95% CI, 0.67-0.75) Failure to ID CA
42/82 calls did not ask about breathing, 16/82 did not ask about type of
breathing. Trigger words: "is dead", "not breathing", "abnormal breathing".
Facial colour "blue", "gray" or "pale" highly associated with CA. "Abnormal
breathing" desrcibed as "occasional breathing, barely/hardly breathing, heavy
breathing, laboured or noisy breathing, sighing, strange breathing".
⨁◯◯◯
VERY
LOW
CRITICAL
control
285 cases (confirmed and suspected
CA)
9230 controls
Matches to MPDS dispatch code, does not address patients in cardiac arrest
Large number of cases excluded for 'technical reason' without adequate explanation. Pre-alert not performed in 480/736 cases – no assessment of accuracy in cases where no pre-alert was performed
Several of the studies were concerned with outcomes post introduction of t-CPR, primary intention not to identify factors associated with recognition of cardiac arrest.
Several studies with small number of participants limiting accuracy. One study reported outcomes by percentage only and did not present actual numbers.
The denominator for the After group for Vaillancourt 2007 does not include 42 eligible cases for which there was no recording. There is no information available on cardiac arrest recognition for the 295 cases from the Before group, so they were not included in the
denominator.
Majority of studies suffer methodologic flaws
Several studies with small numbers, some with many excluded cases
Confounding not adequately controlled for
Sample reported as 9230 confirmed not cardiac arrest, but this is based on sample of 506 cases