A preliminary study of the reliability of immediate vs. delayed interviews of cardiac arrest witnesses

Inter-rater reliability for witnessed collapse and presence of bystander CPR

OBJECTIVE

Witnessed collapse and bystander CPR are the variables most frequently associated with good outcome from out-of-hospital cardiac arrest (OOHCA). The reliability of abstracting witnessed collapse and bystander CPR from prehospital Emergency Medical Services (EMS) patient care records (PCRs) is not known. We sought to determine the inter-rater reliability for different methods of ascertaining and defining witnessed collapse and performance of bystander CPR.

METHODS

A sample of 100 PCRs for patients with OOHCA was selected at random from a pool of 325 PCRs between May 2003 and January 2005. Paramedics used a drop down menu to indicate witnessed collapse and bystander CPR, and completed a narrative description of the event. An on-scene EMS physician also completed a data sheet. The PCR was examined by two separate evaluators to determine the presence of witnessed collapse and bystander CPR. A consensus was reached by three other reviewers using all available data sources. Inter-rater agreement was quantified using the unweighted kappa statistic.

RESULTS

For witnessed collapse, there is substantial agreement between the following: individual evaluators (kappa=0.76, S.D.=0.07), individual evaluators and consensus group (kappa=0.61, S.D.=0.07 and 0.66, S.D.=0.07), and physician and consensus group (kappa=0.68, S.D.=0.08). Agreement between individual evaluators and the physician was fair to moderate (kappa=0.38, S.D.=0.07 and 0.44, S.D.=0.07). Agreement between individual evaluators, physician, consensus group and the PCR drop down menu was fair to moderate (kappa range 0.33, S.D.=0.09 to 0.54, S.D.=0.09). For bystander CPR, there is substantial agreement between the individual evaluators and the consensus group (kappa=0.64, S.D.=0.07 and 0.63, S.D.=0.06) and between the physician and the consensus group (kappa=0.61, S.D.=0.08). Agreement between the two individual evaluators is moderate (kappa=0.59, S.D.=0.07). Agreement between the physician and individual evaluators is fair (kappa=0.36, S.D.=0.07 and 0.38, S.D.=0.07). The PCR drop down menu had moderate to substantial agreement with the individual evaluators, physician, and consensus group (kappa range 0.50, S.D.=0.09 to 0.75, S.D.=0.09).

CONCLUSIONS

Determination of witnessed collapse and bystander CPR during OOHCA may be less reliable than previously thought, and differences between methods of rating could influence study results.

Prehospital delay in acute coronary syndrome—an analysis of the components of delay

BACKGROUND

Prompt hospital admission is essential when treating acute coronary syndrome. Delay prior to admission is unnecessarily long. Therefore, a thorough scrutiny of the influence of characteristics, circumstantial and subjective variables on elements of prehospital delay among patients admitted with acute coronary syndrome is warranted.

METHODS

A structured interview was conducted on 250 consecutive patients admitted alive with acute coronary syndrome.

RESULTS

Median prehospital, decision, physician and transportation delays were 107, 74, 25 and 22 min, respectively. Women (n=77) had more frequently atypical symptoms and increased prehospital delay caused by prolonged physician and transportation delay. Physician delay among women and men were 69 and 16 min, respectively. Patients with prior myocardial infarction had reduced prehospital delay, which was caused by shorter decision and physician delay; whereas patients with prior mechanical revascularisation or typical symptoms had prolonged prehospital delay due to long decision delay. When symptoms were interpreted as cardiac the decision and prehospital delay were reduced.

CONCLUSION

The medical profession underestimates the risk of acute coronary syndrome among women, and thereby contributes to unnecessary long delay to treatment. The patient's prior experience and interpretation has a significant influence on behaviour.

Family perspective of medical care and grief support after field termination by emergency medical services personnel: a preliminary report

OBJECTIVE

To determine the acceptance by family members regarding nontransport of patients in cardiac arrest following unsuccessful resuscitation occurring in private residences.

METHODS

This was a survey with a structured telephone interview. Inclusion criteria included adult patients in asystolic nontraumatic cardiac arrest. The setting was an urban multitiered emergency medical services (EMS) system. Termination of field resuscitation efforts was authorized by an emergency medicine physician at a medical control base station after set protocol criteria. Support services were provided by trained personnel.

RESULTS

Thirty-three follow-up interviews were completed with a family member. Thirty-two (97%) of the contacted family members expressed satisfaction with the services provided by EMS personnel. Twenty-one (64%) patients were not transported to the hospital. All 21 family members of the nontransported were satisfied with both the medical care and the emotional support provided by EMS. Additionally, family members of three of the 12 (25%) transported patients stated they would have preferred to have the patient die at home instead of being transported.

CONCLUSIONS

In this small sample, family members accept the nontransport of patients by trained EMS personnel after asystolic nontraumatic cardiac arrest occurring in private residences. This may positively impact emergency department resources for other critically ill patients.