Table 1 Characteristics of included prospective observational studies
From: The etiology and outcome of non-traumatic coma in critical care: a systematic review
Study | N | Setting | Inclusion | Exclusion | Mortality | Follow-up duration | Country |
|---|---|---|---|---|---|---|---|
Esquevin 2013 [6] | 65 | University ED | GCS ≤ 10, ≥18 yrs, | Trauma, diagnosis such as meningitis, status epilepticus or drug abuse prior to NCCT and CTA, >24 hrs between event and NCCT and CTA, contraindication to iodinated contrast injection, increased or unknown creatinine level | 52% after 3 months | 3 months | France |
Forsberg 2012 [21]†| 865 | University, non-surgical ED | GCS ≤10 maintained for ≥30 min., ≥18 yrs | Coma of unknown cause at discharge or psychogenic, unknown identity of the patient | 27% | 2 years | Sweden |
Forsberg 2012 [9]†| 875 | University, non-surgical ED | GCS ≤10 maintained for ≥30 min., ≥18 yrs | Coma of unknown cause at discharge or psychogenic, >1 plausible coma etiology | 26% | NS | Sweden |
Weiss 2012 [18] | 2189 | University ICU | GCS < 8 in the first 24 hrs of ICU admission |  | 48% | Until discharge | France |
Forsberg 2009 [7]†| 938 | University, Non-surgical ED | GCS ≤10 maintained for ≥30 min., ≥18 yrs | NS | 25% | Until discharge | Sweden |
Greer 2012 [14] | 500 | University, ED, ICU, cardiac or neuroscience ICU | GCS <8 | Coma because of sedating medications or traumatic coma | 87% after 6Â months | 6-months | USA |
Hamel 1995 [19] | 596 | University hospital or ICU | GCS ≤ 9 for ≥6 hrs | Trauma, drug intoxication, hypothermia, operative complication, diabetic ketotic coma, nonketotic hyperosmolar coma, thyrotoxicosis, myxoedema coma, hepatic encephalopathy, uraemia, hypo- or hypernatremia, hypo- or hypercalcaemia. Hospital discharge, death, brain death within 48 hrs of study eligibility | 69% after 2 months | 6-months | USA |
Sacco 1990 [16] | 169 | University ICU | GCS ≤ 8, >10 yrs | Trauma, acute encephalopathy of unknown cause, coma existing > 72 hrs | 54% after 2 weeks | 2-weeks | USA |
Levy 1981 [15] | 500 | University hospital | Coma at admission or during hospitalization, ≥12 yrs | Trauma, drugs | 64% after 1 week | 1-year | USA/UK |
Tokuda 2003 [17] | 115 | Urban teaching hospital ED | GCS < 8, ≥15 yrs | Out of hospital cardiac arrest | NS | Until discharge | Japan |
Owolabi 2013 [12] | 194 | University, non-surgical ED | GCS ≤ 8, ≥18 yrs | Trauma, post anaesthesia coma, coma due to sedative drugs or alcohol | 49% after 1 month | 1 month | Nigeria |
Obiako 2011 [10] | 200 | University, ED | GCS ≤ 8, ≥16 yrs | Trauma, inconclusive diagnosis | NS | 28 days | Nigeria |
Sinclair 1989 [13] | 139‡ | University, ICU | GCS NS, ≥18 yrs | Trauma | NS | Until discharge | Zambia |
Matuja 1987 [11] | 150 | University hospital | GCS ≤ 8 for ≥6 hrs | Transient unresponsiveness, impending death, postictal state, hypoglycaemia | 61% after 1 month | 1-month | Tanzania |