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Delayed presentation to the emergency department influences acute stroke care and can result in worse outcomes. Despite public health messaging, many young adults consider stroke as a disease of older people. We determined the differences in ambulance utilization and delays to hospital presentation between women and men as well as younger (18–44 years) versus older (≥45 years) patients with stroke.
We conducted a population-based retrospective study using national administrative health data from the Canadian Institute of Health Information databases and examined data between 2003 and 2016 to compare ambulance utilization and time to hospital presentation across sex and age.
Young adults account for 3.9% of 463,310 stroke/transient ischemic attack/hemorrhage admissions. They have a higher proportion of hemorrhage (37% vs. 15%) and fewer ischemic events (50% vs. 68%) compared with older patients. Younger patients are less likely to arrive by ambulance (62% vs. 66%, p < 0.001), with younger women least likely to use ambulance services (61%) and older women most likely (68%). Median stroke onset to hospital arrival times were 7 h for older patients and younger men, but 9 h in younger women. There has been no improvement among young women in ambulance utilization since 2003, whereas ambulance use increased in all other groups.
Younger adults, especially younger women, are less likely to use ambulance services, take longer to get to hospital, and have not improved in utilization of emergency services for stroke over 13 years. Targeted public health messaging is required to ensure younger adults seek emergency stroke care.
Limited evidence supports primary care paramedic (PCP) direct transport of ST-segment elevation myocardial infarction (STEMI) patients for percutaneous coronary intervention (PCI). The goal of this study was to evaluate an urban-based PCP STEMI bypass guideline.
We reviewed consecutive Toronto Paramedic Services call reports between April 7, 2015, and May 31, 2016, regarding STEMI patients identified by PCPs. The primary outcome was patient assignment (stable versus unstable) according to guideline criteria. Secondary outcomes were the proportion of PCP-transported patients who had an indication for an advanced care intervention (ACI) or who received an ACI when PCPs rendezvoused with an advanced care paramedic (ACP). Lastly, we reviewed prehospital outcomes of cardiac arrest patients and calculated the difference in transport intervals between direct PCP bypass and a PCI-centre and predicted transport interval to the closest emergency department (ED).
Of 361 patients, 232 were PCP transports and 129 were ACP-rendezvous transports. There was a significant difference in the distribution of stable and unstable patients between PCPs and ACPs (p<0.001). For PCP patients, 21/232 (9.1%) had indications for an ACI, whereas 34/129 (26.4%) ACP patients received an ACI. Eleven patients experienced cardiac arrest; 10 were successfully resuscitated (5 of these by PCPs). The median difference between direct PCP bypass and a PCI-centre versus transport to the closest ED was 5.53 minutes (IQR=6.71).
We found a significant difference in the distribution of stable and unstable patients and fewer patients with indications for an ACI in PCP patients. This PCP STEMI bypass guideline appears feasible.
We conducted a program of research to derive and test the reliability of a clinical prediction rule to identify high-risk older adults using paramedics’ observations.
We developed the Paramedics assessing Elders at Risk of Independence Loss (PERIL) checklist of 43 yes or no questions, including the Identifying Seniors at Risk (ISAR) tool items. We trained 1,185 paramedics from three Ontario services to use this checklist, and assessed inter-observer reliability in a convenience sample. The primary outcome, return to the ED, hospitalization, or death within one month was assessed using provincial databases. We derived a prediction rule using multivariable logistic regression.
We enrolled 1,065 subjects, of which 764 (71.7%) had complete data. Inter-observer reliability was good or excellent for 40/43 questions. We derived a four-item rule: 1) “Problems in the home contributing to adverse outcomes?” (OR 1.43); 2) “Called 911 in the last 30 days?” (OR 1.72); 3) male (OR 1.38) and 4) lacks social support (OR 1.4). The PERIL rule performed better than a proxy measure of clinical judgment (AUC 0.62 vs. 0.56, p=0.02) and adherence was better for PERIL than for ISAR.
The four-item PERIL rule has good inter-observer reliability and adherence, and had advantages compared to a proxy measure of clinical judgment. The ISAR is an acceptable alternative, but adherence may be lower. If future research validates the PERIL rule, it could be used by emergency physicians and paramedic services to target preventative interventions for seniors identified as high-risk.
The parallel advancement of prehospital and in-hospital patient care has provided impetus for the development and implementation of regionalized systems of health care for patients suffering from acute, life-threatening injury and illness. Regardless of the patient’s clinical condition, regionalized systems of care revolve around the premise of providing the right care to the right patient at the right time. Current regionalization strategies have shown improvements in the time to patient treatment and in patient outcome, with the incorporation of emergency medical services (EMS) bypass as a key component of the system of care. This article discusses the emerging role of EMS as a critical component of regionalized systems essential to ensure effective and efficient use of resources to improve patient outcome. We also examine some of the benefits and barriers to implementation of regionalized systems of care and avenues for future research.
Prehospital Code Stroke triage has the potential to overwhelm stroke centres by falsely identifying patients as eligible for fibrinolysis. We sought to determine whether online medical control (whereby paramedics contact the medical control physician before a Code Stroke triage is assigned) reduced the proportion of false-positive Code Stroke patients.
Following the introduction of a protocol for prehospital Code Stroke triage in an urban centre, online medical control alternated with off-line medical control (whereby paramedics implement Code Stroke triage independently) over 4 discreet intervals. We reviewed data for patients triaged to 3 regional stroke centres to compare the proportion of false-positive Code Stroke patients during online versus off-line medical control. We predefined false positives as patients triaged as Code Stroke who had symptoms discovered on awakening, were last seen in their usual state of health greater than 2 hours before assessment or had a final diagnosis other than stroke.
The proportion of false positives was lower during online medical control (31% v. 42%, p = 0.003). This was explained by a lower proportion of patients whose symptoms were discovered on awakening (8% v. 14%, p < 0.001) and who were last seen in their usual state of health greater than 2 hours before assessment (22% v. 32%, p = 0.005). A final diagnosis of stroke was similar in the 2 groups (77% v. 79%, p = 0.39), as was the proportion of patients receiving fibrinolysis (35% v. 33%, p = 0.72). Eighteen percent of patients were denied Code Stroke triage during online control, most commonly because of the time of symptom onset.
Online medical control is associated with a reduced proportion of false-positive Code Stroke triage.
Percutaneous coronary intervention (PCI) appears to be superior to in-hospital fibrinolysis for most patients with ST-elevation myocardial infarction (STEMI). However, few hospitals have PCI capability. The optimal prehospital strategy for facilitating rapid coronary reperfusion in STEMI patients is unclear. We sought to determine whether direct transport of adult STEMI patients by emergency medical services to primary PCI centres improves 30-day all-cause mortality when compared with a strategy of transportation to the closest hospital.
We systematically searched MEDLINE, EMBASE, Cochrane “CENTRAL” database (1980-July 2007) and several other electronic databases. Two authors independently assessed citations for relevance. Two authors independently abstracted data from included studies. We included studies that, 1) transported patients directly to a PCI-capable centre for primary PCI, 2) had a control group that was transported to the closest hospital and 3) reported outcomes of treatment time intervals, all-cause mortality, reinfarction rate, stroke rate or the frequency of cardiogenic shock. We used a random effects model to provide pooled estimates of relative risk (RR) when data allowed.
We identified 2264 citations with the search. Five studies, including 980 STEMI patients, met inclusion criteria, and were clinically heterogeneous and of variable quality. Most studies were European (3/5) and involved physician out-of-hospital care providers. There was a trend toward increased survival with direct transport to primary PCI but this was not statistically significant (RR 0.51, 95% confidence interval [CI] 0.24–1.10). One study reported nonsignificant reductions in reinfarction (RR 0.43, 95% CI 0.11–1.60) and stroke (RR 0.33, 95% CI 0.01–8.06) with direct transport for primary PCI.
There is insufficient evidence to support the effectiveness of direct transport of patients with STEMI for primary PCI when compared with transportation to the closest hospital.
We sought to determine whether the use of currently issued gowns delays initiation of chest compressions and ventilations during cardiopulmonary resuscitation and whether simple gown modifications can reduce this delay.
Firefighter defibrillation instructors were allocated into pairs and videotaped while performing standardized cardiac arrest scenarios. Three scenarios were compared: “no gown,” “standard gown” and “modified gown.” Key time intervals were extracted from videotaped data.
Ninety-five scenarios were analyzed. Mean time interval to chest compression was 39 seconds (95% confidence interval [CI] 34–43) for “no gown” scenarios, 71 seconds (95% CI 66–77) for “standard gown” scenarios and 59 seconds (95% CI 54–63) for “modified gown” scenarios (p < 0.001). Time to first ventilation was 146 seconds (95% CI 134–158), 238 seconds (95% CI 224–253)and 210 seconds (95% CI 198–223) in the 3 groups, respectively (p < 0.001). Post hoc testing showed that the time differences between all groups were statistically significant.
Standard gowns protect front-line care providers but cause significant delays to chest compressions and ventilations, potentially increasing patient morbidity and mortality. Minor gown modifications, including pre-tied neck straps and longer waist ties that tie in front, allow for easier use and shorter delays to time-critical interventions. Future research is required to reduce care delays while maintaining adequate protection of emergency medical service providers from infectious disease.
Deformation of energetic materials may cause undesired reactions and therefore hazardous situations. The deformation of an energetic material and in particular shear deformation is studied in this paper. Understanding of the phenomena leading to shear initiation is not only necessary to explain for example the response of munitions to intrusions or large deformations imposed in storage and transportation accidents. A fundamental understanding of shear initiation also provides the opportunity to initiate energetic materials in a different and controlled manner, and possibly with a tailored reaction rate of the material. Several small and large scale experiments have been performed in which a shear deformation is imposed onto high explosives as well as thermite based reactive materials. Experiments are numerically simulated in order to correlate small and large scale experiments and understand the initiation mechanisms.
Emergency medical services (EMS) responses to
mass gatherings have been described frequently,
but there are few reports describing the response
to a single-day gathering of large magnitude.
This report describes the EMS response to the
largest single-day, ticketed concert held in North
America: the 2003 “Toronto Rocks!” Rolling Stones
Medical care was provided by paramedics,
physicians, and nurses. Care sites included
ambulances, medically equipped, all-terrain
vehicles, bicycle paramedic units, first-aid
tents, and a 124-bed medical facility that
included a field hospital and a rehydration unit.
Records from the first-aid tents, ambulances,
paramedic teams, and rehydration unit were
obtained. Data abstracted included patient
demographics, chief complaint, time of incident,
treatment, and disposition.
More than 450,000 people attended the concert and
1,870 sought medical care (42/10,000 attendees).
No record was kept for the 665 attendees simply
requesting water, sunscreen, or bandages. Of the
remaining 1,205 patients, the average of the ages
was 28 ±11 years, and 61% were female.
Seven-hundred, ninety-five patients (66%) were
cared for at one of the first-aid tents.
Physicians at the tents assisted in patient
management and disposition when crowds restricted
ambulance movement. Common complaints included
headache (321 patients; 27%), heat-related
complaints (148; 12%), nausea or vomiting (91;
7.6%), musculoskeletal complaints (83; 6.9%), and
breathing problems (79; 6.6%). Peak activity
occurred between 14:00 and 19:00 hours, when 102
patients per hour sought medical attention.
Twenty-four patients (0.5/10,000) were transferred
to off-site hospitals.
This report on the EMS response, outcomes, and
role of the physicians at a large single-day mass
gathering may assist EMS planners at future
Clinical prediction rules are decision-making tools that incorporate three or more variables from the history, physical examination or simple tests. They help clinicians make diagnostic or therapeutic decisions by standardizing the collection and interpretation of clinical data. There is growing interest in the methodological standards for their development and validation. This article describes the methods used to derive the Canadian C-Spine Rule and provides a valuable reference for investigators planning to develop future clinical prediction rules.
This paper is Part I of a 2-part series to describe the background and methodology for the Canadian C-Spine Rule study to develop a clinical decision rule for rational imaging in alert and stable trauma patients. Current use of radiography is inefficient and variable, in part because there has been a lack of evidence-based guidelines to assist emergency physicians. Clinical decision rules are research-based decision-making tools that incorporate 3 or more variables from the history, physical examination or simple tests. The Canadian CT Head and C-Spine (CCC) Study is a large collaborative effort to develop clinical decision rules for the use of CT head in minor head injury and for the use of cervical spine radiography in alert and stable trauma victims. Part I details the background and rationale for the development of the Canadian C-Spine Rule. Part II will describe in detail the objectives and methods of the Canadian C-Spine Rule study.
National survival rates for out-of-hospital cardiac arrests are less than 5%, and substantial resources are associated with transporting cardiac arrest victims to hospital for emergency department (ED) resuscitation. The low overall survival rate and the identification of predictors of unsuccessful resuscitation have opened debate on the “futility” of transporting such patients to the ED. This study compares the costs of prehospital pronouncement of death to the costs of transporting patients to a hospital ED for physician pronouncement.
The study was a retrospective chart review on a matched cohort of out-of-hospital cardiac arrest patients. Patients were included if documentation was adequate and ambulance response time was less than 8 minutes. A cohort of 20 patients pronounced dead in the field were matched to 20 patients pronounced dead in an ED. Cases were matched on 6 evidence-based predictors of unsuccessful resuscitation. Direct medical costs and mean physician and prehospital provider times were compared.
The total cost of pronouncement of death in the ED was $45.35 higher than the cost of field pronouncement (p < 0.001). Paramedics spent more time delivering care when death was pronounced in the field (83.3 vs. 55.9 min; p < 0.001). Base hospital physicians spent more time when patients were transported to hospital for ED pronouncement (16.3 vs. 4.3 min; p < 0.001). Total provider time for field pronouncement was 15.5 min longer (p = 0.004), but field pronouncement consumed 12.0 min less physician time.
Paramedic pronouncement of death in the field is less costly than transporting patients to hospital for physician pronouncement. Pronouncement in the field requires more paramedic time but less physician time.
Our primary objectives were to estimate how frequently emergency medical technicians with defibrillation skills (EMT-Ds) are forced to deal with prehospital do-not-resuscitate (DNR) orders, to assess their comfort in doing so, and to describe the prehospital care provided to patients with DNR orders in a system without a prehospital DNR policy (i.e., where resuscitation is mandatory).
Using Dillman methodology, the authors developed a 13-item survey and mailed it to 382 of 764 EMT-Ds in the metropolitan Toronto area. Responses were evaluated using 5-point Likert scales, limited-option and open-ended questions. Narrative responses were categorized. Two authors independently categorized narrative responses from 20 surveys, and kappa values for agreement beyond chance were determined.
Among 382 EMT-Ds surveyed, 236 (62%) responded, of whom 221 (94%) answered the questionnaire. Overall, 126 of 219 (58%) indicated that they were called to resuscitate patients with DNR orders “sometimes,” “frequently,” or “all the time.” In such situations, 22 of 207 (11%) stated they would honour the DNR order and 55 of 207 (27%) would honour the order but appear to provide basic resuscitation, in order to adhere to mandatory resuscitation regulations. Willingness to honour a DNR order did not vary by years of emergency medical service. EMT-Ds cited concern for the family and the patient, fear of repercussions and conflict with personal ethics as key factors contributing to this ethical dilemma. If legally allowed to honour DNR orders, 212 of 221 (96%) respondents would be comfortable with a written order and 137 of 220 (62%) with a verbal order.
Prehospital DNR orders are common, and a significant number of EMT-Ds disregard current regulations by honouring them. EMT-Ds would be more comfortable with written than verbal DNR orders. An ethical prehospital DNR policy should be developed and applied.