Apnea test during brain death assessment in 142 mechanically ventilated and 25 venoarterialECMO patients
Marco Giani, Vittorio Scaravilli, Sebastiano Maria Colombo, Andrea Confalonieri, Rosambra Leo, Elena
Maggioni, Leonello Avalli, Alessia Vargiolu, Giuseppe Citerio
Supplementary material
Page 2. Additional Methods
Page 3. Additional Results
Page 6. Additional References
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Additional Methods
Data Collection
All the data were collected with Innovian® Solution Suite (Draeger Medical, Lubeck, Germany) that
automatically digitally stores data from vital signs monitors at 150Hz (then averaged every 60 seconds),
laboratory (including point of care blood gas analyses), ventilators and other medical devices along with
medical and clinical charts. Demographic data, weight, diagnosis at ICU admission, ICU length of stay
(LOS), and connection to ECMO circuit at the time of BD determination were recorded from clinical charts.
To assess whether our approach is associated with lung tissue damage and subsequent poor
transplantation outcomes, donor status, eventual lung harvesting and lung donor score (i.e. OTO score [1])
were retrieved from the local transplant registry.
To evaluate feasibility of the AT, the following major complications were recorded: test interruptions,
pneumothorax and pneumomediastinum, cardiac arrhythmias, cardiac arrest, hypoxia and hypotension.
To evaluate the incidence of hypotension we compared the arterial pressure 10 minutes before the AT and
at the end of it. We also investigated the incidence of severe hypoxia at the end of the AT, defined as a PaO2
less than 40 mmHg on the blood gas analyses sampled at the end of the apnea period. In the event that
blood gas analyses documented severe hypoxia, to assess the duration and impact of the episode, the
electronic chart of the patient was further screened and peripheral capillary oxygen saturation (SpO2)
tracing retrieved. SpO2 values were thus collected starting from 5 minutes prior to 5 minutes after the
blood gas analyses.
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Additional Results
ECMO details
All the ECMO patients were supported by a circuit consisting in a polymethylpentene heparin-coated
hollow-fiber membrane lung and a centrifugal pump, either Maquet PLS (35%) (Maquet
Cardiopulmonary, Rastatt, Germany) and or CardioHelp (65%) (Maquet Cardiopulmonary, Rastatt,
Germany).
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Fig. S1 Study population.
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Figure S2. Time course of peripheral capillary oxygen saturation (SpO2) of the 11 severe hypoxic
episodes. during the 5 minutes before and after arterial blood gas analysis (BGA) withdrawal
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Additional references
1.
Oto T, Levvey BJ, Whitford H, et al. (2007) Feasibility and utility of a lung donor score: correlation with
early post-transplant outcomes. Ann Thorac Surg. 83(1):257-63. doi: 10.1016/j.athoracsur.2006.07.040
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