Dispatcher-assisted cardiopulmonary resuscitation and survival in cardiac arrest.

BACKGROUND: Early cardiopulmonary resuscitation (CPR) improves survival in out-of-hospital cardiac arrest, and dispatcher-delivered instruction in CPR can increase the proportion of arrest victims who receive bystander CPR before emergency medical service (EMS) arrival. However, little is known about the survival effectiveness of dispatcher-delivered telephone CPR instruction. METHODS AND RESULTS: We evaluated a population-based cohort of EMS-attended adult cardiac arrests (n=7265) from 1983 through 2000 in King County, Washington, to assess the association between survival to hospital discharge and 3 distinct CPR groups: no bystander CPR before EMS arrival (no bystander CPR), bystander CPR before EMS arrival requiring dispatcher instruction (dispatcher-assisted bystander CPR), and bystander CPR before EMS arrival not requiring dispatcher instruction (bystander CPR without dispatcher assistance). In this cohort, 44.1% received no bystander CPR before EMS arrival, 25.7% received dispatcher-assisted bystander CPR, and 30.2% received bystander CPR without dispatcher assistance. Overall survival was 15.3%. Using no bystander CPR as the reference group, the multivariate adjusted odds ratio of survival was 1.45 (95% confidence interval [CI], 1.21, 1.73) for dispatcher-assisted bystander CPR and 1.69 (95% CI, 1.42, 2.01) for bystander CPR without dispatcher assistance. CONCLUSION: Dispatcher-assisted bystander CPR seems to increase survival in cardiac arrest.

The partial nontandem duplication of the MLL (ALL1) gene is a novel rearrangement that generates three distinct fusion transcripts in B-cell acute lymphoblastic leukemia.

A partial nontandem duplication (PNTD) of mixed lineage leukemia (MLL) gene is described in B-cell acute lymphoid leukemia without structural cytogenetic abnormalities at 11q23 and 9p22. A duplicated portion of MLL is interrupted by the insertion of a region of 9p22 that includes the 3'-end of the AF9 gene. The PNTD encodes: (a) a PNTD transcript; (b) a partial tandem duplication of MLL; and (c) a chimeric transcript fusing MLL to the 3'-end of AF9, mimicking the t(9;11)(p22;q23) and expressed 1024-fold higher than the other two. The MLL PNTD, therefore, contributes toward leukemogenesis through simultaneous production of fusion transcripts that are otherwise encoded by three distinct genetic defects.

Localization of FCGR1 encoding Fcgamma receptor class I in primates: molecular evidence for two pericentric inversions during the evolution of human chromosome 1.

The human high-affinity receptor for immunoglobulin G, FcgammaRI (FCGR1), is encoded by a family of three genes that share over 95% sequence homology. Curiously, the three genes in this recently duplicated gene family flank the centromere of human chromosome 1, with FCGR1B located at 1p12 and both FCGR1A and FCGR1C located at 1q21. We have previously speculated that a pericentric inversion could account for the separation of the genes in the FCGR1 family and explain their current chromosomal location. Here we present evidence, obtained through fluorescence in situ hybridization analysis, that in the rhesus monkey (Macaca mulatta) and baboon (Papio papio) FCGR1 is located adjacent to the centromere on the chromosomal arm with greatest homology to human 1p, whereas in the chimpanzee (Pan troglodytes) it is located adjacent to the centromere on the chromosomal arm with greatest homology to human 1q. The separation of the FCGR1 gene family in humans suggests that the location of a second pericentric inversion, known to distinguish the human from the chimpanzee chromosome 1, is within the FCGR1 gene family. This finding refines the assignment of homology between the human and chimpanzee chromosomes 1.

Increasing the efficiency of emergency medical services by using criteria based dispatch.

STUDY OBJECTIVES: To determine whether criteria based dispatch (CBD) improved the efficiency of the emergency medical services system. DESIGN: A before and after design was used to measure effects of CBD. Data were reviewed from medical reports from January 1986 through June 1992. SETTING: King County, Washington, excluding the city of Seattle. PARTICIPANTS: Residents who called 911 to report a medical emergency. INTERVENTIONS: Emergency medical dispatching (EMD), basic life support (BLS), and advanced life support (ALS). RESULTS: Findings show a decrease in ALS responses for two tracer conditions that medical control physicians determined not require ALS intervention. The percentage of febrile seizures in which paramedics responded decreased from 41% to 21% (P < .001). The percentage of cerebrovascular accidents in which paramedics responded decreased from 41% to 28% (P < .001). CBD led to a decrease, from 4.7% to 3.8% (P < .001), in frequency of requests by BLS units for dispatch of ALS units. There was no increase in the time required to dispatch each call. CONCLUSION: CBD increased the efficiency of the EMS system by significantly reducing ALS responses to incidents not requiring ALS intervention and reducing requests by BLS units for dispatch of ALS units while maintaining a consistent time from receipt of call to dispatch.

Incidence of agonal respirations in sudden cardiac arrest.

STUDY OBJECTIVE: To discover the frequency of agonal respirations in cardiac arrest calls, the ways callers describe them, and discharge rates associated with agonal respirations. DESIGN: We reviewed taped recordings of calls reporting cardiac arrests and emergency medical technician and paramedic incident reports for 1991. Arrests after arrival of emergency medical services were excluded. SETTING: King County, Washington, excluding the city of Seattle. PARTICIPANTS: Four hundred forty-five persons with out-of-hospital cardiac arrests receiving emergency medical services. INTERVENTIONS: Telephone CPR, emergency medical technicians-defibrillation, and advanced life support by paramedics. MEASUREMENTS AND MAIN RESULTS: Any attempts at breathing described by callers were identified, as well as whether agonal respirations could be heard by dispatcher, emergency medical technicians, or paramedics. Agonal respirations occurred in 40% of 445 out-of-hospital cardiac arrests. Callers described agonal breathing in a variety of ways. Agonal respirations were present in 46% of arrests caused by cardiac etiology compared with 32% in other etiologies (P < .01). Fifty-five percent of witnessed arrests had agonal activity compared with 16% of unwitnessed arrests (P < .001). Agonal respirations occurred in 56% of arrests with a rhythm of ventricular fibrillation compared with 34% of cases with a nonventricular fibrillation rhythm (P < .001). Twenty-seven percent of patients with agonal respirations were discharged alive compared with 9% without them (P < .001). CONCLUSION: There is a high incidence of agonal activity associated with out-of-hospital cardiac arrest. Presence of agonal respirations is associated with increased survival. These findings have implications for public CPR training programs and emergency dispatcher telephone CPR programs.

Dispatcher-assisted telephone CPR: common delays and time standards for delivery.

STUDY OBJECTIVES: To determine the rate of bystander CPR before and after implementation of a telephone CPR program in King County; to determine the reasons for dispatcher delays in identifying patients in cardiac arrest in delivering CPR instructions over the telephone; and to suggest time standards for delivery of the telephone CPR message. DESIGN: An ongoing cardiac arrest surveillance system to calculate the annual bystander CPR rates from 1976 through 1988. Two hundred sixty-seven taped recordings of calls reporting cardiac arrests to nine emergency dispatch centers during 1988 were reviewed and timed. SETTING: King County, Washington, excluding the city of Seattle. PARTICIPANTS: Two hundred sixty-seven persons with out-of-hospital cardiac arrests receiving emergency medical services. Arrests in doctors' offices, clinics, or nursing homes were excluded. INTERVENTIONS: Dispatcher-assisted telephone CPR. MEASUREMENTS AND MAIN RESULTS: The rate of bystander CPR increased from 32% (1976 through 1981) to 54% (1982 through 1988) after implementation of the dispatcher-assisted telephone CPR program, although an increase in survival could not be demonstrated. The median time for dispatchers to identify the problem was 75 seconds; to deliver the early protocols, 19 seconds; to deliver the ventilation instructions, 25 seconds; and to deliver compression instructions, 30 seconds. The total time to deliver the entire CPR message was 2.3 minutes. The most frequent cause for delay was unnecessary questions (57%) with questions about patient age asked most frequently (32%). Other causes included the caller not being near the patient (29%) and deviations from protocol (22%). CONCLUSION: In a metropolitan emergency medical services system, a dispatcher-assisted telephone CPR program was associated with an increase in bystander CPR. Delays in proper delivery of telephone CPR can be minimized through training.