Table 1.
Overview of the studies included in the systematic literature search.
| Author | Year | Type of Study | Device Used | n | Relation rSO2- PNC | rSO2 Threshold | Outcome Measured | Measuring Complications |
|---|---|---|---|---|---|---|---|---|
| Negargar (49) | 2007 | PO | INVOS | 72 | No | Absolute decrease <40% and 50%, >20% absolute desturation from baseline | Neuropsychological state | MMSE |
| De Tournay-Jetté (50) | 2011 | PO | INVOS | 61 | Yes | Absolute decrease <50%, >30% decrease from baseline | Early (4–7 days) and late (1 month) POCD (drop of 1SD from baseline (the day before surgery) on ≥2 more neuropsychologic indices) | Trail Making Test part A and B, Verbal Fluency Test, Ray's Auditory Verbal Learning Test, Logical Memory Subtest (Rivermead battery), digit symbol, Stroop Test |
| Fischer (51) | 2011 | PO | Fore-sight | 30 | Yes | Absolute decrease <50%, <55%, <60%, <65% | Severe adverse outcome, including stroke | not specified |
| Schoen (52) | 2011 | PO | INVOS | 231 | Yes | Absolute decrease <50% absolute, >80% decrease baseline | Delirium | MMSE, CAM-ICU |
| Hong (53) | 2008 | PO | INVOS | 100 | No | Absolute decrease <40%, 50%, >20% decrease from baseline | POCD | MMSE, Trail-Making Test (Part A), Grooved Pegboard Test |
| Fudickar (54) | 2011 | PO | Niro | 35 | Yes | Absolute decrease <65% | Postoperative cognitive deficit | Trail Making Test, Verbal Learning Test, Ray's Auditorial Verbal Fluency Test, Digit Symbol Substitution Test, Digit Span Test |
| Olsson (55) | 2006 | RO | INVOS | 46 | Yes | None | Stroke | New neurologic deficit that did not resolve before discharge confirmed by CT and/or specialist neurologic assessment |
| Urbanski (56) | 2013 | PO | Niro | 122 | No | Absolute decrease ≤55%, <80% change from baseline | Adverse neurological outcome (permanent focal neurological deficit or temporary neurological dysfunction) | Permanent focal neurological deficit: confirmed by a neurologist and CT or MRI. Temporary neurological dysfunction: confusion, delirium, agitation or temporary focal deficits without evidence on CT or MRI. |
| Kakihana (57) | 2012 | PO | Hamamatsu | 10 | Yes | None | Stroke | MMSE |
| Hassan (58) | 2010 | POP | Fore-sight | 1 | Yes | Absolute decrease <55% | Neurocognitive deficit | not reported |
| Greenberg (59) | 2013 | PO | Fore-sight | 53 | No | Absolute decrease <60% ≥60 seconds in ≥1 hemisphere | Delirium | not reported |
| Senanayake (60) | 2012 | PO | INVOS | 27 | Yes | None | Permanent or temporary neurological deficit | Permanent neurological deficit: any new postoperative neurological deficit that included new focal stroke or global coma which did not resolve by discharge, and confirmed by a new cerebral infraction on CT. Temporary neurological deficit: any postoperative neurological deficit that included motor deficit, confusion, agitation, or transient delirium that resolved spontaneously before discharge with no new cerebral infarction on CT. |
| Kamenskaya (61) | 2015 | PO | INVOS | 61 | Yes | Absolute decrease <40% | Neurological complications (encephalopathy, stroke) | MMSE, GCS |
| Murkin (62) | 2007 | PRI | INVOS | 194 | No | AUC <70% of baseline >150 minutes∙%, desaturation AUC <40% asbolute | Stroke | Focal neurologic deficit persisting >24hrs and confirmed by CT |
| Colak (45) | 2015 | PI | INVOS | 200 | Yes | Absolute decrease <50%, AUC >150%∙min <20% of baseline, AUC >50min∙% | Cognitive decline | MMSE, Color Trail Test 1, Grooved-Pegboard Test |
| Slater (63) | 2009 | PRI | INVOS | 240 | Yes | Desaturation score >3000 | Early POCD | Neurocognitive test battery |
| Kok (64) | 2014 | PIP | INVOS (but both INVOS and Fore-sight were measured) | 60 | No | AUC 40% >10 minutes∙% | Postoperative cognitive decline (4 days (early) and 3 months (late)) | CogState brief computerised cognitive test battery |
| Mohandas (65) | 2013 | PI | Equanox | 100 | Yes | >20% decrease from baseline | PNC | MMSE, ASEM |
| Colak (66) | 2012 | PI | INVOS | 58 | Yes | AUC>150 minutes∙% for <20% of baseline or >50 minutes∙% for <50% of absolute value | Stroke, coma, stupor | Coma: profound state of unconsciousness without response to verbal call, pain or any other stimulus. Stupor: state of unconsciousness from which patient can be aroused only by vigorous physical stimulation. Stroke: acute onset of a neurologic deficit that persists for at least 24 hours and reflects focal involvement of the central nervous system. Delirium/encephalopathy: confusion, agitation, disorientation, decreased alertness, sleep disturbances, memory deficit or seizure without obvious focal neurological deficit. |
| Murkin (67) | 2011 | PI | INVOS | 57 | No | Decrease <75% of baseline >15 seconds. | New-onset stroke, major-organ morbidity and mortality | Unclear |
ASEM, antisaccadic eye movement; AUC, area under curve; CAM-ICU, confusion assessment method on the intensive care unit; CT, computed tomography; GCS, Glasgow coma scale; MMSE, mini-mental state examination; MRI, magnetic resonance imaging; PI, prospective interventional; PIP, prospective interventional pilot; PNC, postoperative neurological complication; PO, prospective observational; POCD, postoperative cognitive dysfunction; POP, prospective observational pilot; PRI, prospective randomized interventional; RO, retrospective observational; rSO2, regional cerebral tissue oxygen saturation.