Author | Sample size | Age range | Study type | ‘Cold’ tool | Temperature (°C) | Apnoea method employed | Duration (s) | Reversion success (%) | History of previous SVT | Rhythm | HDR performance position |
Bisset et al6 | 10 | 1 day–15 years | Prospective interventional, non-randomised | Ice and water in plastic bag | Not stated | Covered nose and mouth | 1–15 | 100 | Yes (5), No (5) | PSVT | Supine |
Sreeram et al5 | 16 | Birth-1 year | Retrospective case review | Iced water | Not stated | Apnoea consequent of complete facial immersion | 5 | 89.8 | Not stated | PAT | Not stated |
Whitman et al3 | 1 | 8 years | Case study | Ice water | Not stated | Breath holding during facial immersion | ‘Instantaneous’ | 100 | Yes | PSVT | Not stated |
Whitman et al20 | 2 | 7 and 10 days (2 cases) | Case series | Ice and water | Not stated | Breath holding during facial immersion | 6 and 4–5 | 100 | Case 1: not stated, Case 2: yes | PSVT (both cases) | Not stated (both cases) |
Craig et al21 | 1 | 14 days | Case study | Ice to face | Not stated | Not stated | Not stated | 100 | Yes | PSVT | Not stated |
Sperandeo et al23 | 10 | 14 days–5 months | Prospective interventional, non-randomised | Iced water | 4–5 | Breath holding during facial immersion | 6–7 | 100 | Yes | PSVT | Not stated |
HDR, human dive reflex; PAT, paroxysmal atrial tachycardia; PSVT, paroxysmal supraventricular tachycardia; SVT, supraventricular tachycardia.