Table 1

Primary outcome measures

Minor mechanical complicationsMajor mechanical complications
Bleeding grade 2*Bleeding grades 3 and 4†
Arrhythmia grades 1 and 2‡Arrhythmia grades 3 and 4§
Arterial punctureArterial catheterisation
Non-persistent nerve injury¶Persistent nerve injury**
Failed catheterisationPneumothorax
Catheter tip malposition††
  • *Bleeding/haematoma formation requiring external compression.

  • †Bleeding/haemothorax requiring invasive intervention or blood transfusion and bleeding with life-threatening consequences.

  • ‡Asymptomatic arrhythmia not requiring intervention and asymptomatic/symptomatic arrhythmia requiring non-urgent medical intervention.

  • §Symptomatic arrhythmia requiring urgent medical intervention and arrhythmia with life-threatening consequences.

  • ¶Nerve injury with clinical signs persisting up to 72 hours.

  • **Nerve injury with clinical signs persisting more than 72 hours.

  • ††Catheter tip malposition requiring correction before use.