Temporal changes in blood pressure following prehospital rapid sequence intubation.

BACKGROUND: Rapid Sequence intubation (RSI) is an airway procedure that uses sedative and paralytic drugs to facilitate endotracheal intubation. It is known that RSI could impact blood pressure in the peri-intubation period. However, little is known about blood pressure changes in longer time frames. Therefore, this analysis aims to describe the changes in systolic blood pressure in a large cohort of paramedic-led RSI cases over the whole prehospital timespan. METHODS: Intensive Care Paramedics in Victoria, Australia, are authorised to use RSI in medical or trauma patients with a Glasgow Coma Scale <10. This retrospective cohort study analysed data from patientcare records for patients aged 12 years and above that had received RSI, from 1 January 2008 to 31 December 2019. This study quantifies the systolic blood pressure changes using regression with fractional polynomial terms. The analysis is further stratified by high versus Low Shock Index (LSI). The shock index is calculated by dividing pulse rate by systolic blood pressure. RESULTS: During the study period RSI was used in 8613 patients. The median number of blood pressure measurements was 5 (IQR 3-8). Systolic blood pressure rose significantly by 3.4 mm Hg (p<0.001) and then returned to baseline in the first 5 min after intubation for LSI cases. No initial rise in blood pressure is apparent in High Shock Index (HSI) cases. Across the whole cohort, systolic blood pressure decreased by 7.1 mm Hg (95% CI 7.9 to 6.3 mm Hg; p<0.001) from the first to the last blood pressure measured. CONCLUSIONS: Our study shows that in RSI patients a small transient elevation in systolic blood pressure in the immediate postintubation period is found in LSI, but this elevation is not apparent in HSI. Blood pressure decreased over the prehospital phase in RSI patients with LSI, but increased for HSI cases.

The utility of the brain trauma evidence to inform paramedic rapid sequence intubation in out-of-hospital stroke.

BACKGROUND: Rapid sequence intubation (RSI) is used to secure the airway of stroke patients. Randomized controlled trial evidence exists to support the use of paramedic RSI for traumatic brain injury (TBI), but cannot necessarily be applied to stroke RSI because of differences between the stroke and TBI patient. To understand if the TBI evidence can be used for stroke RSI, we analysed a retrospective cohort of TBI and strokes to compare how survival is impacted differently by RSI when comparing strokes and TBI. METHODS: This study was a retrospective analysis of 10 years of in-hospital and out-of-hospital data for all stroke and TBI patients attended by Ambulance Victoria, Australia. Logistic regression predicted the survival for ischemic and haemorrhagic strokes as well as TBI. The constituents of RSI, such a medications, intubation success and time intervals were analysed against survival using interactions to asses if RSI impacts survival differently for strokes compared to TBI. RESULTS: This analysis found significant interactions in the RSI-only group for age, number of intubation attempts, atropine, fentanyl, pulse rate and perhaps scene time and time- to-RSI. Such interactions imply that RSI impact survival differently for TBI versus strokes. Additionally, no significant difference in survival for TBI was found, with a - 0.7% lesser survival for RSI compared to no-RSI; OR 0.86 (95% CI 0.67 to 1.11; p = 0.25). Survival for haemorrhagic stroke was - 14.1% less for RSI versus no-RSI; OR 0.44 (95% CI 0.33 to 0.58; p = 0.01) and was - 4.3%; OR 0.67 (95% CI 0.49 to 0.91; p = 0.01) lesser for ischemic strokes. CONCLUSIONS: Rapid sequence intubation and related factors interact with stroke and TBI, which suggests that RSI effects stroke survival in a different way from TBI. If RSI impact survival differently for strokes compared to TBI, then perhaps the TBI evidence cannot be used for stroke RSI.

The association of paramedic rapid sequence intubation and survival in out-of-hospital stroke.

INTRODUCTION: Ambulance transport of patients with stroke is common, with rapid sequence intubation (RSI) to secure the airway used regularly. Randomised controlled trial evidence exists to support the use of RSI in traumatic brain injuries (TBIs), but it is not clear whether the RSI evidence from TBI can be applied to the patient with stroke. To this end, we analysed a retrospective stroke dataset to compare survival of patients with RSI compared with patients that did not receive RSI. METHODS: This study was a retrospective analysis of 10 years of in-hospital and out-of-hospital data for all patients with stroke attended by Ambulance Victoria, in Victoria Australia. Generalised boosted logistic regression was used to predict propensity scores, with initial vital signs, age and demographic variables as well as measures of illness severity and comorbidity included in the prediction model. This analysis employed a 1:1 nearest-neighbour matching which was applied to generate a dataset from which we calculated the OR of survival to hospital discharge of patients receiving RSI versus no-RSI. The sensitivity of these results to unmeasured confounding was assessed with deterministic sensitivity analysis. RESULTS: The propensity score-matched cohort showed a decreased survival for RSI in strokes with an OR 0.61 (95% CI 0.45 to 0.82; p=0.001) when compared with no-RSI. A subgroup analysis showed no significant survival difference for ischaemic strokes: OR 0.66 (95% CI 40 to 1.07; p=0.09). The survival for haemorrhagic stroke was OR 0.60 (95% CI 0.41 to 0.90; p=0.01) lesser for RSI. Results were likely robust to unmeasured confounding and missing data. CONCLUSIONS: Our retrospective analysis shows a decrease in survival when RSI is utilised by paramedics for stroke. Since RSI is commonly used for strokes, controlled trial evidence to support this practice is urgently needed.

Paramedic Attendance to Older Patients in Australia, and the Prevalence and Implications of Psychosocial Issues.

OBJECTIVE: This study aims to determine the number and reasons for emergency paramedic attendances to older adults in Victoria, Australia. A second aim is to investigate the prevalence of psychosocial factors that may contribute to older patients requiring emergency paramedic attendance. METHODS: This descriptive retrospective study analyzed all emergency paramedic attendances to patients aged 65 or older between July 1, 2011 and June 30, 2014 in Victoria, Australia. Fully de-identified data were extracted from the Ambulance Victoria Data Warehouse. Data included demographic and clinical variables such as age, gender, case nature (cause), past history, management and transportation, paramedic final assessment (diagnosis), social situation, past history; as well as free text case descriptions. RESULTS: A total of 596,579 patients 65 years or older were attended by emergency paramedics during the study period. This accounted for 24.1% of Ambulance Victoria workload during that period. The mean (SD) age of patients was 79.8(8.2). The majority (70.7%) of cases involved patients at private residences. The most common final assessments were pain (18.7%), cardiac problem (7.2%), infection (6.9%), trauma (6.7%), other/unknown (6.4%), and respiratory problem (5.7%). The vast majority of patients were transported to hospital (82.8%). Psychosocial issues were evident in the free text case descriptions of more than 91,000 cases. CONCLUSION: Paramedics attended almost 600,000 patients 65 years and older during the study period. Patients suffered from conditions including, pain, trauma, infections, cardiac complaints, and respiratory problems. Free text case descriptions provided more detail and insight into the reasons for emergency paramedic attendance. Psychosocial problems were far more prevalent than indicated by the "final assessment" field. Further research is required to determine the reasons and implications of this.

Survival in Out-of-hospital Rapid Sequence Intubation of Non-Traumatic Brain Pathologies.

INTRODUCTION: Rapid sequence intubation (RSI) is not only used in traumatic brain injuries in the out-of-hospital setting, but also for non-traumatic brain pathologies (NTBP) such as brain tumors, meningitis, encephalitis, hypoxic/anoxic brain injury, stroke, arteriovenous malformations, tumors, aneurysms, brain hemorrhage, as well as brain injury due to diabetes, seizures and toxicity, metabolic conditions, and alcohol and drug overdose. Previous research suggests that RSI is common in non-traumatic coma, but with an unknown prevalence of NTBP in those that receive RSI. If NTBP is common and if brain trauma RSI evidence is not valid for NTBP then a sizable proportion of NTBP receive this treatment without evidence of benefit. This study calculated the out-of-hospital NTBP prevalence in patients that had received RSI and explored factors that predicted survival. METHODS: A retrospective cohort study based on data collected from an ambulance service and seven hospitals based in Melbourne, Australia. Non-traumatic brain pathologies were defined using ICD10-AM codes for the calculation of NTBP prevalence. Logistic regression modelled out-of-hospital predictors of survival to hospital discharge after adjustment for comorbidities. RESULTS: The seven participating hospitals treated 2,277 patients that received paramedic RSI for all illnesses and indications from January 1, 2008 to December 31, 2015, with survival data available for 1,940 (85%). Of the 1,940, 1,125 (58%) patients had at least one hospital-diagnosed NTBP. Sixty-nine percent all of NTBP survived to hospital discharge, compared to 65% for traumatic intracranial injury. Strokes were the most common and had poor survival to discharge (37%) compared to the second most common NTBP toxicity/toxic encephalopathy that had very high survival (98%). No out-of-hospital clinical intervention or prehospital time interval predicted survival. Factors that did predict survival include Glasgow Coma Scale (GCS), duration of mechanical ventilation, age, ICU length of stay, and comorbidities. CONCLUSIONS: Non-traumatic brain pathologies are seven times more prevalent than traumatic brain injuries in patients that underwent out-of-hospital RSI in Victoria, Australia. Since the mechanisms through which RSI impacts mortality might differ between traumatic brain injuries and NTBP, and given that NTBP is very prevalent, it follows that the use of RSI in NTBP could be unsupported.

Epidemiology of prehospital pain: an opportunity for improvement.

This retrospective, electronic patient care record review examined a consecutive sample of patients presenting with pain to the metropolitan region of Ambulance Victoria over a period of 12 months in 2008. The majority of patients did not achieve clinically significant pain reduction, but did achieve some pain relief while in ambulance care. Those with the most severe pain had pain reduction that was clinically significant. Further research is needed to provide optimal pain relief in the prehospital setting.

Physician presence at out-of-hospital cardiac arrest is not necessarily the cause of improved survival.

A recent publication Hiltunen et al. on Out-of-Hospital Cardiac Arrest (OHCA) in Finland show increased survival when a physician attends an OHCA, compared to EMS. But it is likely that physicians attend OHCA patients with a different prognosis due to comorbidity or illness severity, which causes confounding by indication and is the likely cause for the physician and survival association.