Background
Methods
Design
Setting and population
Randomisation
Treatment protocol
Outcomes
Survival to discharge and 90 days
Analysis
Results
Paramedic recruitment
Number of OHCA during the study period
Study patients
Arm A 100% oxygen (n = 17) | Arm B titrated oxygen (n = 18) | Total (n = 35) | ||
---|---|---|---|---|
Sex | Female n (%) | 5 (29) | 5 (28) | 10 |
Male n (%) | 12 (71) | 13 (72) | 25 | |
Age (mean, years) | 64 | 70 | 67 | |
Witnessed | No n(%) | 3 (18) | 1 (6) | 4 |
Yes n(%) | 14 (82) | 17 (94) | 31 | |
EMS witnessed | No n(%) | 15 (88) | 9 (50) | 24 |
Yes n(%) | 2 (12) | 9 (50) | 11 | |
Bystander cardiopulmonary resuscitation | EMS witnessed n(%) | 2 (12) | 9 (50) | 11 |
No n(%) | 4 (24) | 4 (22) | 8 | |
Yes n(%) | 11 (64) | 5 (28) | 16 | |
First monitored rhythm | Shockable n (%) | 6 (35) | 10 (56) | 16 |
Non shockable n (%) | 10 (59) | 6 (33) | 16 | |
Missing n (%) | 1 (6) | 2 (11) | 3 |
Method of airway management used - Arm A - 100% oxygen (n = 17) | |||||
Tracheal tube | Supraglottic airway device | Oropharyngeal airway | Other | Missing | |
On loading into the ambulance n (%) | 6 (35) | 4 (24) | 2 (12) | 2 (12) | 1 (6) |
En route to ED n (%) | 0 | 0 | 0 | 1 (6) | 14 (82) |
On arrival at ED n (%) | 8 (47 | 1 (6) | 1 (6) | 2 (12) | 3 (18) |
Not Conveyed | 2 patients | ||||
Method of airway management used - Arm B - Titrated oxygen (n = 18) | |||||
On loading into the ambulance n (%) | 3 (17) | 3 (17) | 3 (17) | 6 (33) | 2 (11) |
En Route to ED n (%) | 0 | 0 | 1 (6) | 1 (6) | 15 (83) |
On arrival at ED n (%) | 5 (28) | 1 (6) | 1 (6) | 6 (33) | 4 (22) |
Not Conveyed | 1 patient |
Arm A 100% oxygen (n = 17) | Arm B titrated oxygen (N = 18) | Total (n = 35) | |
---|---|---|---|
Re-arrest following initial ROSC | 8 (47) | 3 (17) | |
Death recognised on scene n (%)* | 2 (12) | 1 (6) | 3 (18) |
Survival to discharge n (%) | 3 (18) | 10 (55) | 13 (37) |
Survival to 90 days n (%) | 3 (18) | 10 (55) | 13 (37) |
Intervention success
Oxygen saturations recorded- Arm A - 100% oxygen (n = 17) | ||||
SpO2 ≤ 94% | SpO2 > 94% | Missing Data | Unable to Measure | |
On loading into ambulance n (%) | 3 (18) | 6 (35) | 2 (12) | 4 (24) |
En Route to ED n (%) | 3 (18) | 7 (41) | 1 (6) | 4 (24) |
On arrival at ED n (%) | 2 (12) | 7 (41) | 2 (12) | 4 (24) |
Not Conveyed | 2 Patients | |||
Oxygen saturations recorded - Arm B titrated oxygen (n = 18) | ||||
On loading into ambulance n (%) | 4 (22) | 8 (44) | 1 (6) | 4 (22) |
En Route to ED n (%) | 5 (28) | 8 (44) | 1 (6) | 3 (17) |
On arrival to ED n (%) | 5 (28) | 8 (44) | 1 (6) | 3 (17) |
Not Conveyed | 1 Patient |
If self –inflating bag ventilation; flow rate l/min - Arm A 100% Oxygen (n = 17) | |||||
< 15 l/min | 15 l/min | Mechanically Ventilated 100% oxygen | Missing Data | Nil – maintaining SpO2 values with air | |
On loading n (%) | 1 (6) (10 l/min) | 9 (53) | 1 (6) | 3 (18) | 1 (6) |
En Route to ED n (%) | 0 | 6 (35) | 5 (29) | 3 (18) | 1 (6) |
On arrival at ED n (%) | 0 | 6 (35) | 5 (29) | 3 (18) | 1 (6) |
Non Conveyed n (%) | 2 Patients | ||||
If self-inflating bag ventilation; flow rate l/min - Arm B Titrated Oxygen (n = 18) | |||||
Flow Rate n (%) | < 15 l/min | 15 l/min | Mechanically Ventilated 100% oxygen | Missing Data | Nil – maintaining SpO2 values with airown saturations |
On loading n (%) | 4 (22) (8–12 l/min) | 5 (28) | 2 (11) | 3 (17) | 3 (17) |
En Route to ED n (%) | 4 (22) 1–12 l/min) | 3 (17) | 2 (11) | 2 (11) | 3 (17) |
On arrival at ED n (%) | 3 (17) (12 l/min) | 3 (17) | 1 (6) | 2 (11) | 4 (22) |
Non Conveyed | 1 Patient |
Clinical outcomes
Patient follow up at 90 days
Discussion
Summary of principal findings
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We have shown that amongst UK paramedics it is potentially feasible to perform a trial of titrated oxygen in the first hour following ROSC after OHCA.
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Recruitment of paramedics can be difficult in the UK setting.
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Accurate recording of SpO2 values is challenging or impossible in some patients, and measures must be taken to avoid hypoxia in these individuals.
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Paramedics are willing and able to follow an algorithm for oxygen titration.