PhD Student and Lecturer, Monash University
Prehospital anaesthesia can be performed safely and effectively by specialist paramedics
Helicopter emergency medical services (HEMS) staffed by those capable of providing advanced clinical interventions offer an invaluable service to critically-ill patients. HEMS deliver highly-skilled clinicians directly to patients requiring critical clinical interventions and enable rapid transport to definitive care. One such skill is Rapid Sequence Intubation (RSI). A number of studies have described paramedic-led RSI, however debate continues as to whether paramedics are competent in the provision of this procedure, and what the effect is on morbidity and mortality. A smaller number of studies have focused specifically on RSI in the paediatric population. The postulated benefits of RSI are numerous, however the procedure carries with it a number of risks . Although a randomised trial of paramedic RSI has been undertaken in adult patients suffering traumatic brain injury, the likelihood of such a trial being conducted in the paediatric population is very low. We sought to investigate RSI in paediatric patients as performed by the paramedics of Air Ambulance Victoria HEMS (AAV-HEMS), with a focus on intubation first-pass success, and the effects of RSI on physiological parameters.
Abstract: Secondary brain injury may occur early after severe traumatic brain injury due to hypoxia and/or hypotension. Prehospital care by ambulance paramedics has the goal of preventing and treating these complications and, thus, improving outcomes. In Australia, most ambulance services recommend paramedics attempt endotracheal intubation in patients with severe head injury. Even though most patients with severe head injury retain airway reflexes, most states do not allow the use of appropriate drugs to facilitate intubation. In contrast, recent evidence from trauma registries suggests that this approach may be associated with significantly worse outcomes compared with no intubation. Two states allow intubation facilitated by sedative (but not relaxant) drugs, but this has a low success rate and could worsen brain injury because of a decrease in cerebral perfusion pressure. For road-based paramedics, the role of rapid sequence intubation is uncertain. Given the risks of this procedure and the lack of proven benefit, this procedure should not be introduced without supportive evidence from randomised, controlled trials. In contrast, for safety reasons, comatose patients transported by helicopter should undergo rapid sequence intubation prior to flight. However, this is not authorised in most states, despite good supportive evidence that this can be safely and effectively undertaken by paramedics. Finally, there is evidence that inadvertent hyperventilation is associated with adverse outcome, yet only two ambulance services use waveform capnography in head injury patients who are intubated. Overall, current paramedic airway practice in most states of Australia is not supported by the evidence and is probably associated with worse patient outcomes after severe head injury. For road-based paramedics, rapid transport to hospital without intubation should be regarded as the current standard of care. Rapid sequence intubation should be limited to use within appropriate clinical trials, or patients transported by helicopter. For patients who are intubated, waveform capnography is essential to confirm tracheal placement and to prevent inadvertent hyperventilation.
Pub.: 23 May '06, Pinned: 29 Aug '17
Abstract: To determine whether paramedic rapid sequence intubation in patients with severe traumatic brain injury (TBI) improves neurologic outcomes at 6 months compared with intubation in the hospital.Severe TBI is associated with a high rate of mortality and long-term morbidity. Comatose patients with TBI routinely undergo endo-tracheal intubation to protect the airway, prevent hypoxia, and control ventilation. In many places, paramedics perform intubation prior to hospital arrival. However, it is unknown whether this approach improves outcomes.In a prospective, randomized, controlled trial, we assigned adults with severe TBI in an urban setting to either prehospital rapid sequence intubation by paramedics or transport to a hospital emergency department for intubation by physicians. The primary outcome measure was the median extended Glasgow Outcome Scale (GOSe) score at 6 months. Secondary end-points were favorable versus unfavorable outcome at 6 months, length of intensive care and hospital stay, and survival to hospital discharge.A total of 312 patients with severe TBI were randomly assigned to paramedic rapid sequence intubation or hospital intubation. The success rate for paramedic intubation was 97%. At 6 months, the median GOSe score was 5 (interquartile range, 1-6) in patients intubated by paramedics compared with 3 (interquartile range, 1-6) in the patients intubated at hospital (P = 0.28).The proportion of patients with favorable outcome (GOSe, 5-8) was 80 of 157 patients (51%) in the paramedic intubation group compared with 56 of 142 patients (39%) in the hospital intubation group (risk ratio, 1.28; 95% confidence interval, 1.00-1.64; P = 0.046). There were no differences in intensive care or hospital length of stay, or in survival to hospital discharge.In adults with severe TBI, prehospital rapid sequence intubation by paramedics increases the rate of favorable neurologic outcome at 6 months compared with intubation in the hospital.
Pub.: 26 Nov '10, Pinned: 29 Aug '17
Abstract: 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.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.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.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.
Pub.: 18 Jun '17, Pinned: 29 Aug '17
Abstract: The optimal staffing of helicopter emergency medical services (HEMS) is uncertain. An intensive care paramedic-staffed HEMS has operated in the state of Victoria, Australia for over 28 years, with paramedics capable of performing advanced procedures, including rapid sequence intubation, decompression of tension pneumothorax, and cricothyroidotomy. Administration of a wide range of vasoactive, anesthetic, and analgesic medications is also permitted. We sought to explore the characteristics of patients transported by HEMS in Victoria, and describe paramedic utilization of their skill set in the prehospital environment.A retrospective data review was conducted of patients transported by the HEMS between 1 July 2012 and 30 June 2013. Data were sourced from the Ambulance Victoria data warehouse and the Victorian State Trauma Registry. Interhospital transfers were excluded.HEMS attended 1,519 cases during the study period. A total of 825 primary transport cases were included in analyses. Most patients were male (69.5%) and the majority of cases involved trauma (86.1%). Rapid sequence intubation (RSI) was performed in 36.8% of pediatric and 29.9% of adult major trauma patients, with a procedural success rate of 100%. Ketamine was administered to 18.5% of all trauma patients. The proportion of patients with a severe pain score (≥7) decreased from 33.8 to 3.2% (p < 0.001) between initial and final paramedic assessments. A clinically significant pain reduction of ≥2 points was achieved by 87.0% (95% CI 82.9-90.4%) of adult trauma patients who had an initial pain score >2 points and a valid final pain score. In-hospital mortality following major-trauma was 7.6% (95% CI 5.0-11.0%).The skill set of HEMS intensive care paramedics in Victoria is broad, including a large number of prehospital critical care procedures commonly utilized by physician-staffed HEMS in other jurisdictions. A high RSI procedural success rate was observed across the study period, as were significant improvements in patient physiological parameters and pain scores.
Pub.: 18 Feb '15, Pinned: 29 Aug '17
Abstract: Pre-hospital intubation by paramedics is widely used in comatose patients prior to transportation to hospital, but the optimal technique for intubation is uncertain. One approach is paramedic rapid sequence intubation (RSI), which may improve outcomes in adult patients with traumatic brain injury. However, many patients present to emergency medical services with coma of non-traumatic cause and the role of paramedic RSI in these patients remains uncertain.The electronic Victorian Ambulance Clinical Information System was searched for the term 'suxamethonium' between 2008 and 2011. We reviewed the patient care records and included patients with suspected non-traumatic coma who were treated and transported by road-based paramedics. Demographics, intubation conditions, vital signs (before and after drug administration) and complications were recorded. Younger patients (<60 years) were compared with older patients.There were 1152 paramedic RSI attempts of which 551 were for non-traumatic coma. The success rate for intubation was 97.5%. There was a significant drop in blood pressure in younger patients (<60 years) with the mean systolic blood pressure decreasing by 16 mm Hg (95% CI 11 to 21). In older patients, the systolic blood pressure also decreased significantly by 20 mm Hg (95% CI 17 to 24). Four patients suffered brief cardiac arrest during pre-hospital care, all of whom were successfully resuscitated and transported to hospital.Paramedic RSI in patients with non-traumatic coma has a high procedural success rate. Further studies are required to determine whether this procedure improves outcomes.
Pub.: 30 Jan '14, Pinned: 29 Aug '17