Endovascular treatment for vaccine-induced cerebral venous sinus thrombosis and thrombocytopenia following ChAdOx1 nCoV-19 vaccination: a report of three cases

BACKGROUND

Vaccine-induced thrombosis and thrombocytopenia (VITT) is a rare complication following ChAdOx1 nCoV-19 vaccination. Cerebral venous sinus thrombosis (CVST) is overrepresented in VITT and is often associated with multifocal venous thromboses, concomitant hemorrhage and poor outcomes. Hitherto, endovascular treatments have not been reviewed in VITT-related CVST.

METHODS

Patient records from a tertiary neurosciences center were reviewed to identify patients who had endovascular treatment for CVST in VITT.

RESULTS

Patient records from 1 January 2021 to 20 July 2021 identified three patients who underwent endovascular treatment for CVST in the context of VITT. All were female and the median age was 52 years. The location of the CVST was highly variable. Two-thirds of the patients had multifocal dural sinus thromboses (sigmoid, transverse, straight and superior sagittal) as well as internal jugular vein thromboses. Intracerebral hemorrhage occurred in all patients; subarachnoid blood was noted in two of them, and intraparenchymal hemorrhage occurred in all. There was one periprocedural parenchymal extravasation which abated on temporary cessation of anticoagulation. Outcome data revealed a 90-day modified Rankin Scale (mRS) score of 2 in all cases.

CONCLUSIONS

We demonstrate that endovascular treatment for VITT-associated CVST is feasible and can be safe in cases that deteriorate despite medical therapy. Extensive clot burden, concomitant hemorrhage, rapid clinical progression and persistent rises in intracranial pressure should initiate multidisciplinary team discussion for endovascular treatment in appropriate cases.

Apnoeic oxygenation for emergency anaesthesia of pre-hospital trauma patients

BACKGROUND

Efficient and timely airway management is universally recognised as a priority for major trauma patients, a proportion of whom require emergency intubation in the pre-hospital setting. Adverse events occur more commonly in emergency airway management, and hypoxia is relatively frequent. The aim of this study was to establish whether passive apnoeic oxygenation was effective in reducing the incidence of desaturation during pre-hospital emergency anaesthesia.

METHODS

A prospective before-after study was performed to compare patients receiving standard care and those receiving additional oxygen via nasal prongs. The primary endpoint was median oxygen saturation in the peri-rapid sequence induction period, (2 minutes pre-intubation to 2 minutes post-intubation) for all patients. Secondary endpoints included the incidence of hypoxia in predetermined subgroups.

RESULTS

Of 725 patients included; 188 patients received standard treatment and 537 received the intervention. The overall incidence of hypoxia (first recorded SpO₂ < 90%) was 16.7%; 10.9% had SpO₂ < 85%. 98/725 patients (13.5%) were hypoxic post-intubation (final SpO₂ < 90% 10 minutes post-intubation). Median SpO₂ was 100% vs. 99% for the standard vs. intervention group. There was a statistically significant benefit from apnoeic oxygenation in reducing the frequency of peri-intubation hypoxia (SpO₂ < =90%) for patients with initial SpO₂ > 95%, p = 0.0001. The other significant benefit was observed in the recovery phase for patients with severe hypoxia prior to intubation.

CONCLUSION

Apnoeic oxygenation did not influence peri-intubation oxygen saturations, but it did reduce the frequency and duration of hypoxia in the post-intubation period. Given that apnoeic oxygenation is a simple low-cost intervention with a low complication rate, and that hypoxia can be detrimental to outcome, application of nasal cannulas during the drug-induced phase of emergency intubation may benefit a subset of patients undergoing emergency anaesthesia.

Best practice advice on pre-hospital emergency anaesthesia & advanced airway management

BACKGROUND

Effective and timely airway management is a priority for sick and injured patients. The benefit and conduct of pre-hospital emergency anaesthesia (PHEA) and advanced airway management remains controversial but there are a proportion of critically ill and injured patients who require urgent advanced airway management prior to hospital arrival. This document provides current best practice advice for the provision of PHEA and advanced airway management.

METHOD

This best practice advice was developed from EHAC Medical Working Group enforced by pre-hospital critical care experts. The group used a nominal group technique to establish the current best practice for the provision of PHEA and advanced airway management. The group met on three separate occasions to discuss and develop the guideline. All members of the working party were able to access and edit the guideline online.

RESULTS

This EHAC best practice advice covers all areas of PHEA and advanced airway management and provides up to date evidence of current best practice.

CONCLUSION

PHEA and advanced airway management are complex interventions that should be delivered by appropriately trained personnel using a well-rehearsed approach and standardised equipment. Where advanced airway interventions cannot be delivered, careful attention should be given to applying basic airway interventions and ensuring their effectiveness at all times.

Airway management in pre-hospital critical care: a review of the evidence for a 'top five' research priority

The conduct and benefit of pre-hospital advanced airway management and pre-hospital emergency anaesthesia have been widely debated for many years. In 2011, prehospital advanced airway management was identified as a ‘top five’ in physician-provided pre-hospital critical care. This article summarises the evidence for and against this intervention since 2011 and attempts to address some of the more controversial areas of this topic.

Prehospital emergency anaesthesia: an updated survey of UK practice with emphasis on the role of standardisation and checklists

INTRODUCTION

Prehospital emergency anaesthesia (PHEA or 'prehospital rapid sequence intubation') is a high-risk procedure. Standard operating procedures (SOPs) and checklists within healthcare systems have been demonstrated to reduce human error and improve patient safety. We aimed to describe the current practice of PHEA in the UK, determine the use of checklists for PHEA and describe the content, format and layout of any such checklists currently used in the UK.

METHOD

A survey of UK prehospital teams was conducted to establish the incidence and conduct of PHEA practice. Results were grouped into systems delivering a high volume of PHEA per year (>50 PHEAs) and low volume (≤50 PHEAs per annum). Standard and 'crash' (immediate) induction checklists were reviewed for length, content and layout.

RESULTS

59 UK physician-led prehospital services were identified of which 43 (74%) participated. Thirty services (70%) provide PHEA and perform approximately 1629 PHEAs annually. Ten 'high volume' services deliver 84% of PHEAs per year with PHEA being performed on a median of 11% of active missions. The most common indication for PHEA was trauma. 25 of the 30 services (83%) used a PHEA checklist prior to induction of anaesthesia and 24 (80%) had an SOP for the procedure. 19 (76%) of the 'standard' checklists and 5 (50%) of the 'crash' induction checklists used were analysed. On average, standard checklists contained 169 (range: 52-286) words and 41 (range: 28-70) individual checks. The style and language complexity varied significantly between different checklists.

CONCLUSION

PHEA is now performed commonly in the UK. The use of checklists for PHEA is relatively common among prehospital systems delivering this intervention. Care must be taken to limit checklist length and to use simple, unambiguous language in order to maximise the safety of this high-risk intervention.

Cardiac troponin T is associated with mortality in patients admitted to critical care in a UK major trauma centre: a retrospective database analysis

Background

Elevated levels of cardiac troponin T are associated with poor outcome in critically ill patients and have been proposed as a prognostic marker in major trauma. This study investigated the relationship between cardiac troponin T levels on admission to intensive care unit (ICU) and all-cause mortality in major trauma patients.

Methods

A retrospective database analysis of cardiac troponin T levels on admission to the ICU in major trauma patients between 1 August 2015 and 31 December 2016 at a UK Major Trauma Centre was performed.

Results

Of the 243 patients, 69 (28.4%) died. Cardiac troponin T levels were significantly higher in patients who died compared to survivors: 42 vs. 13 ng/L, respectively (p < 0.0001); the odds of all-cause mortality increased significantly as troponin increased, independent of age or Acute Physiology and Chronic Health Evaluation score.

Discussion

This confirms cardiac troponin T at ICU admission as a marker of mortality in major trauma. Elevated cardiac troponin T may be seen in patients without evidence of direct cardiac trauma.

Pre-hospital emergency anaesthesia in awake hypotensive trauma patients: beneficial or detrimental?

BACKGROUND

The benefits of pre-hospital emergency anaesthesia (PHEA) are controversial. Patients who are hypovolaemic prior to induction of anaesthesia are at risk of severe cardiovascular instability post-induction. This study compared mortality for hypovolaemic trauma patients (without major neurological injury) undergoing PHEA with a patient cohort with similar physiology transported to hospital without PHEA.

METHODS

A retrospective database review was performed to identify patients who were hypotensive on scene [systolic blood pressure (SBP) < 90 mmHg], and GCS 13-15. Patient records were reviewed independently by two pre-hospital clinicians to identify the likelihood of hypovolaemia. Primary outcome measure was mortality defined as death before hospital discharge.

RESULTS

Two hundred and thirty-six patients were included; 101 patients underwent PHEA. Fifteen PHEA patients died (14.9%) compared with six non-PHEA patients (4.4%), P = 0.01; unadjusted OR for death was 3.73 (1.30-12.21; P = 0.01). This association remained after adjustment for age, injury mechanism, heart rate and hypovolaemia (adjusted odds ratio 3.07 (1.03-9.14) P = 0.04). Fifty-eight PHEA patients (57.4%) were hypovolaemic prior to induction of anaesthesia, 14 died (24%). Of 43 PHEA patients (42.6%) not meeting hypovolaemia criteria, one died (2%); unadjusted OR for mortality was 13.12 (1.84-578.21). After adjustment for age, injury mechanism and initial heart rate, the odds ratio for mortality remained significant at 9.99 (1.69-58.98); P = 0.01.

CONCLUSION

Our results suggest an association between PHEA and in-hospital mortality in awake hypotensive trauma patients, which is strengthened when hypotension is due to hypovolaemia. If patients are hypovolaemic and awake on scene it might, where possible, be appropriate to delay induction of anaesthesia until hospital arrival.

AAGBI: Safer pre-hospital anaesthesia 2017: Association of Anaesthetists of Great Britain and Ireland

Pre-hospital emergency anaesthesia with oral tracheal intubation is the technique of choice for trauma patients who cannot maintain their airway or achieve adequate ventilation. It should be carried out as soon as safely possible, and performed to the same standards as in-hospital emergency anaesthesia. It should only be conducted within organisations with comprehensive clinical governance arrangements. Techniques should be straightforward, reproducible, as simple as possible and supported by the use of checklists. Monitoring and equipment should meet in-hospital anaesthesia standards. Practitioners need to be competent in the provision of in-hospital emergency anaesthesia and have supervised pre-hospital experience before carrying out pre-hospital emergency anaesthesia. Training programmes allowing the safe delivery of pre-hospital emergency anaesthesia by non-physicians do not currently exist in the UK. Where pre-hospital emergency anaesthesia skills are not available, oxygenation and ventilation should be maintained with the use of second-generation supraglottic airways in patients without airway reflexes, or basic airway manoeuvres and basic airway adjuncts in patients with intact airway reflexes.

The success of pre-hospital tracheal intubation by different pre-hospital providers: a systematic literature review and meta-analysis

BACKGROUND

Pre-hospital basic airway interventions can be ineffective at providing adequate oxygenation and ventilation in some severely ill or injured patients, and advanced airway interventions are then required. Controversy exists regarding the level of provider required to perform successful pre-hospital intubation. A previous meta-analysis reported pre-hospital intubation success rates of 0.849 for non-physicians versus 0.991 for physicians. The evidence base on the topic has expanded significantly in the last 10 years. This study systematically reviewed recent literature and presents comprehensive data on intubation success rates.

METHODS

A systematic search of MEDLINE and EMBASE was performed using PRISMA methodology to identify articles on pre-hospital tracheal intubation published between 2006 and 2016. Overall success rates were estimated using random effects meta-analysis. The relationship between intubation success rate and provider type was assessed in weighted linear regression analysis.

RESULTS

Of the 1838 identified studies, 38 met the study inclusion criteria. Intubation was performed by non-physicians in half of the studies and by physicians in the other half. The crude median (range) reported overall success rate was 0.969 (0.616-1.000). In random effects meta-analysis, the estimated overall intubation success rate was 0.953 (0.938-0.965). The crude median (range) reported intubation success rates for non-physicians were 0.917 (0.616-1.000) and, for physicians, were 0.988 (0.781-1.000) (p = 0.003).

DISCUSSION

The reported overall success rate of pre-hospital intubation has improved, yet there is still a significant difference between non-physician and physician providers. The finding that less-experienced personnel perform less well is not unexpected, but since there is considerable evidence that poorly performed intubation carries a significant risk of morbidity and mortality careful consideration should be given to the training and experience required to deliver this intervention safely.

Advanced airway management for pre-hospital trauma patients

The need for timely and appropriate airway management for trauma patients is widely recognised. There are a small number of severely injured patients who cannot be adequately supported with basic airway manoeuvres, and require early advanced airway management. The way in which this care is provided remains highly controversial. Whilst it is clear that effective airway management remains a priority for all patients and poorly performed pre-hospital anaesthesia may be detrimental to patient outcome, debate remains over exactly which patients will benefit from early advanced airway interventions, and how it should be provided. The evidence base is small and inconsistent, with significant heterogeneity in the reported data, making it impossible to draw meaningful conclusions. Current practice is not standardised, and care is delivered by providers of different abilities using a range of equipment and techniques. Standards of care provided during in-hospital practice relating to these issues of provider competence, equipment, and monitoring should be directly translated into delivery of care outside the hospital, but this is not always the case. The aim of this review is to evaluate the current evidence surrounding pre-hospital advanced airway management.

Pre-hospital anaesthesia: the same but different

Advanced airway management is one of the most controversial areas of pre-hospital trauma care and is carried out by different providers using different techniques in different Emergency Medical Services systems. Pre-hospital anaesthesia is the standard of care for trauma patients arriving in the emergency department with airway compromise. A small proportion of severely injured patients who cannot be managed with basic airway management require pre-hospital anaesthesia to avoid death or hypoxic brain injury. The evidence base for advanced airway management is inconsistent, contradictory and rarely reports all key data. There is evidence that poorly performed advanced airway management is harmful and that less-experienced providers have higher intubation failure rates and complication rates. International guidelines carry many common messages about the system requirements for the practice of advanced airway management. Pre-hospital rapid sequence induction (RSI) should be practiced to the same standard as emergency department RSI. Many in-hospital standards such as monitoring, equipment, and provider competence can be achieved. Pre-hospital and emergency in-hospital RSI has been modified from standard RSI techniques to improve patient safety, physiological disturbance, and practicality. Examples include the use of opioids and long-acting neuromuscular blocking agents, ventilation before intubation, and the early release of cricoid pressure to improve laryngoscopic view. Pre-hospital RSI is indicated in a small proportion of trauma patients. Where pre-hospital anaesthesia cannot be carried out to a high standard by competent providers, excellent quality basic airway management should be the mainstay of management.

Management of the trauma airway

A priority for all trauma patients is rapid assessment and appropriate, prompt and effective management of the airway. Adequate ventilation and tissue oxygenation can prevent hypoxic injury, particularly within the central nervous system. Failure to secure the airway soon enough is a major cause of preventable death following significant injury (Ivatury and Guilford, 2008). Many controversial issues surround the management of the trauma airway including the effect of early tracheal intubation on morbidity and mortality, the variation in failed intubation rates for paramedics compared with physicians, and the use of manual in-line stabilisation and cricoid pressure during tracheal intubation. Studies have attempted to address these and other questions related to airway management in trauma patients. Unfortunately, many variables within the studies make interpretation of the results difficult. This review aims to summarise the key issues in relation to all of these controversies.

Evaluation of a single-use intubating videoscope (Ambu aScope ™) in three airway training manikins for oral intubation, nasal intubation and intubation via three supraglottic airway devices

We compared the Ambu aScope™ with a conventional fibrescope in two simulated settings. First, 22 volunteers performed paired oral and nasal fibreoptic intubations in three different manikins: the Laerdal Airway Trainer, Bill 1 and the Airsim (a total of 264 intubations). Second, 21 volunteers intubated the Airway Trainer manikin via three supraglottic airways: classic and intubating laryngeal mask airways and i-gel (a total of 66 intubations). Performance of the aScope was good with few failures and infrequent problems. In the first study, choice of fibrescope had an impact on the number of user-reported problems (p=0.004), and user-assessed ratings of ease of endoscopy (p<0.001) and overall usefulness (p<0.001), but not on time to intubate (p=0.19), or ease of railroading (p=0.72). The manikin chosen and route of endoscopy had more consistent effects on performance: best performance was via the nasal route in the Airway Trainer manikin. In the second study, the choice of fibrescope did not significantly affect any performance outcome (p=0.3), but there was a significant difference in the speed of intubation between the devices (p=0.02) with the i-gel the fastest intubation conduit (mean (SD) intubation time i-gel 18.5 (6.8) s, intubating laryngeal mask airway = 24.1 (11.2) s, classic laryngeal mask airway = 31.4 (32.5) s, p=0.02). We conclude that the aScope performs well in simulated fibreoptic intubation and (if adapted for untimed use) would be a useful training tool for both simulated fibreoptic intubation and conduit-assisted intubation. The choice of manikin and conduit are also important in the success of such training. This manikin study does not predict performance in humans and a clinical study is required.

Outcome from paediatric cardiac arrest associated with trauma

OBJECTIVE

To examine survival rates for paediatric trauma patients requiring cardiopulmonary resuscitation (CPR) in the pre-hospital setting, and to identify characteristics that may be associated with survival.

DESIGN

Ten-year retrospective trauma database review.

SETTING

An urban physician-led pre-hospital trauma service serving a population of approximately 7.5 million, in the United Kingdom.

PATIENTS

Eighty paediatric trauma patients (15 years or less) who received pre-hospital resuscitation following cardiorespiratory arrest between July 1994 and June 2004.

INTERVENTION

Pre-hospital cardiopulmonary resuscitation.

MAIN OUTCOME MEASURE

Survival to hospital discharge.

RESULTS

Eighty children met inclusion criteria for the study. Nineteen (23.8%) were discharged alive from the emergency department and seven children (8.75%) survived to hospital discharge. Of the seven survivors, one had spinal cord injury. Two suffered asphyxial injury associated with blunt trauma and three sustained hypoxic insults following drowning or burns/smoke inhalation. In one patient with known congenital cardiac disease the cause of cardiac arrest was likely to have been medical.

CONCLUSION

This study confirms the poor outcome for children requiring pre-hospital CPR following trauma. However, the results are better in this physician-attended group than in other studies where physicians were not present. They also suggest that cardiac arrest associated with trauma in children has a better outcome than in adults. In common with adults treated in this system, those patients with hypovolaemic cardiac arrest did not survive (Ann Emerg Med 2006;48:240-4). A large proportion of the survivors suffered hypoxic or asphyxial injuries. Targeted aggressive out-of-hospital resuscitation in certain patient groups can produce good outcomes.

Traumatic Cardiac Arrest: Who Are the Survivors?

STUDY OBJECTIVE

Survival from traumatic cardiac arrest is poor, and some consider resuscitation of this patient group futile. This study identified survival rates and characteristics of the survivors in a physician-led out-of-hospital trauma service. The results are discussed in relation to recent resuscitation guidelines.

METHODS

A 10-year retrospective database review was conducted to identify trauma patients receiving out-of-hospital cardiopulmonary resuscitation. The primary outcome measure was survival to hospital discharge.

RESULTS

Nine hundred nine patients had out-of-hospital cardiopulmonary resuscitation. Sixty-eight (7.5% [95% confidence interval 5.8% to 9.2%]) patients survived to hospital discharge. Six patients had isolated head injuries and 6 had cervical spine trauma. Eight underwent on-scene thoracotomy for penetrating chest trauma. Six patients recovered after decompression of tension pneumothorax. Thirty patients sustained asphyxial or hypoxic insults. Eleven patients appeared to have had "medical" cardiac arrests that occurred before and was usually the cause of their trauma. One patient survived hypovolemic cardiac arrest. Thirteen survivors breached recently published guidelines.

CONCLUSION

The survival rates described are poor but comparable with (or better than) published survival rates for out-of-hospital cardiac arrest of any cause. Patients who arrest after hypoxic insults and those who undergo out-of-hospital thoracotomy after penetrating trauma have a higher chance of survival. Patients with hypovolemia as the primary cause of arrest rarely survive. Adherence to recently published guidelines may result in withholding resuscitation in a small number of patients who have a chance of survival.