Table 2.
Platelet function
| Reference | Study design | TBI type | Age category | Patients (n) | Antithrombotic treatment (n, %) | Hemostatic comorbidities | Sampling times | First sample | Result |
|---|---|---|---|---|---|---|---|---|---|
| Nekludov [30] | Prospective observational | Isolated severe TBI | Adults | 20 | 0 (0%) | Alcoholism in 50%. Excluded those with other known coagulation disorders | On admission and 3 days after injury | 17 ± 12 h after injury | Below-normal platelet function on admission (Multiplate: AA/ASPI and ADP), that returned to normal by day 3 in most cases although some patients normalized after 2–3 weeks |
| Vecht [38] | Prospective observational | Moderate to severe TBI | N/A | 34 | N/A | N/A | On admission and 1, 2, 3, 4, 5, 9 days and 2, 3, 4, 5, 6 weeks after injury | < 2 h of injury | Below-normal platelet function on admission (Vitatron spectrophotometer: ADP), with the lowest value on day 2, that returned to normal after 9–16 days |
| Kutcher [23] | Prospective observational | TBI | N/A | 62 | 5 (8%) | N/A | On admission and 6, 12, 24, 48, 72, 96, 120 h after injury | N/A | Low-to-normal platelet function on admission (Multiplate: ADP, TRAP, AA/ASPI, COL), that decreased to below-normal levels 6 h after injury, before returning to normal after 24 h (TRAP, COL), 96 h (ADP) or 120 h (AA/ASPI) |
| Briggs [32] | Prospective interventional | Isolated TBI | Adults | 5 | 0 (0%) | Excluded those with history of thrombocytopenia, platelet disorder, or other preexisting coagulopathy | On admission and 4–12 h after injury | N/A | Below-normal platelet function on admission (Multiplate: COL), with the lowest value after 4–12 h. Same trend for AA/ASPI but within reference ranges |
| Lindblad [37] | Retrospective | TBI, admitted to ICU | Adults | 178 | 47 (26%) | N/A | N/A | N/A | Below-normal and decreasing platelet function (Multiplate®: AA/ASPI) during first 10 h after injury, that returned to normal after 4–5 days. Results independent of COX-inhibition and platelet transfusion |
| Guillotte [36] | Prospective observational | TBI | Adults | 153 | 62 (41%) | N/A | N/A | N/A | Below-normal and decreasing platelet function in moderate-to-severe TBI (TEG: ADP) during first 24 h after injury. Results independent of antithrombotic medication |
AA/ASPI acetylsalicylic acid test; ADP adenosine diphosphate test; COL collage test; h hours; N/A not available; TBI traumatic brain injury; TEG thromboelastography; TRAP thrombin receptor activating peptide-6 test