Unconsciousness (Loss of Consciousness)

Loss of the ability to maintain awareness of self and environment combined with markedly reduced responsiveness to environmental stimuli. (From Adams et al., Principles of Neurology, 6th ed, pp344-5)

Also Known As:

Networked: 957 relevant articles (10 outcomes, 53 trials/studies)

Relationship Network

Disease Context: Research Results

Related Diseases

1.	Pain (Aches)
2.	Abdominal Pain (Pain, Abdominal)
3.	Syncope (Fainting)
4.	Headache (Headaches)
5.	Craniocerebral Trauma (Head Injury)

Experts

1.	Laureys, Steven: 9 articles (01/2014 - 01/2010)
2.	Purdon, Patrick L: 8 articles (10/2015 - 12/2010)
3.	Brown, Emery N: 8 articles (10/2015 - 12/2010)
4.	Schneider, Gerhard: 8 articles (05/2015 - 11/2004)
5.	Hudetz, Anthony G: 8 articles (09/2014 - 07/2006)
6.	Boveroux, Pierre: 8 articles (01/2014 - 01/2010)
7.	Kochs, Eberhard F: 6 articles (05/2015 - 11/2004)
8.	Vanhaudenhuyse, Audrey: 6 articles (01/2014 - 01/2010)
9.	Boly, Mélanie: 6 articles (01/2013 - 01/2010)
10.	Noirhomme, Quentin: 6 articles (01/2013 - 01/2010)

Drugs and Biologics

Drugs and Important Biological Agents (IBA) related to Unconsciousness:

1.	Propofol (Diprivan)FDA LinkGeneric 03/01/2014 - "The goal of the present study was to investigate whether the median (50%) effective effect-concentration (EC50) of propofol inducing loss of consciousness (LOC) varies between the luteal and the follicular phases of the menstrual cycle. " 11/01/2013 - "In this study, simultaneous records of functional magnetic resonance imaging (fMRI) and electroencephalogram were performed to investigate the causality of neural mechanisms during propofol-induced loss of consciousness by correlating FC in fMRI and directional connectivity (DC) in electroencephalogram. " 01/01/2013 - "The aim of the present study was to investigate, in healthy humans during an auditory task, the changes in effective connectivity resulting from propofol induced loss of consciousness. " 07/01/2012 - "In this study we determined the dose of propofol that caused loss of consciousness in 95% (ED(95)) of obese and nonobese children as determined by loss of eye lash reflex. " 12/01/2009 - "The aim of this study was to investigate whether predicted site-effect propofol concentrations, A-line Autoregressive Index (AAI) and SE values are useful for predicting loss of verbal contact (LVC) and loss of consciousness (LOC) during steady-state conditions. "
2.	Fentanyl (Sublimaze)FDA LinkGeneric 08/01/1998 - "The time until loss of consciousness was significantly less in the groups receiving fentanyl than the groups without fentanyl (P < 0.01). " 01/01/1995 - "Induction of anesthesia was realized with fentanyl at speed of 500 mcg x min-1 until loss of consciousness was reached (no answer to three consecutive questions). " 01/01/2007 - "Although infiltration of recurrent lymphoma to the brain became apparent, she remained active, without epilepsy or loss of consciousness, in a general ward for 1 month with transdermal fentanyl, treatment until she again became drowsy; she died on hospital day 58. " 10/01/1998 - "We investigated whether fentanyl decreases the serum concentrations of the steroid anesthetic eltanolone effective in producing loss of consciousness in 50% of patients (EC50induction) and in preventing movement at skin incision in 50% of patients (EC50incision). " 11/01/2007 - "The effect-site concentrations of fentanyl at the symptom and propofol at loss of consciousness were measured. "
3.	sevoflurane (Ultane)FDA LinkGeneric 10/01/2008 - "By evaluating sevoflurane-induced loss of consciousness in the presence of low brain concentrations of N2O in 38 elective surgical patients, N2O was associated with a statistically significant reduction in the input the frontal cortex received from other cortical and subcortical areas. " 05/01/2015 - "Highest incidence of disagreement occurred after state transitions, in particular for state entropy after loss of consciousness during sevoflurane anaesthesia. " 02/01/2014 - "Although the time to loss of consciousness was significantly lower using the 8% method (75.98 vs 135 seconds), the liquid sevoflurane consumption using the incremental method (2.25 mL) was almost half that of the fixed 8% method (4.46 mL). " 02/01/2014 - "The prediction of anaesthetic events, including skin incision, first reaction of motor movement during emergence period, loss of consciousness (LOC) and return of consciousness (ROC) by NRR were evaluated by serial prediction probability (PK ) analysis; the ability to predict the decrease of effect-site sevoflurane concentration was also evaluated. " 01/01/2014 - "The inspired concentration of sevoflurane was increased to 7% until loss of consciousness and then reduced back to 2%. "
4.	Carbon MonoxideIBA 10/01/2015 - "This article discusses the case history of an 87-year old woman with loss of consciousness following accidental CO intoxication. " 03/01/2015 - "Predictors of mortality on univariate analysis were age ≥ 60 years, male sex, loss of consciousness, high NIHSS score (≥16), the presence of co-morbid conditions and presence of complications. " 05/01/2014 - "There was a history of accidental carbon monoxide intoxication one month before, presenting with loss of consciousness and short hospitalization, followed by a complete clinical recovery. " 03/01/2013 - "Exposure to 90C causes a higher aversive reaction but a quicker loss of consciousness than N(2)/CO(2) gas mixtures. " 03/01/2012 - "The delayed neurological sequelae group had a longer duration of carbon monoxide exposure, a longer duration of loss of consciousness, and a worse mental status (p-value < 0.001). "
5.	Lidocaine (Xylocaine)FDA LinkGeneric 10/01/2001 - "After the loss of consciousness, laryngoscopy and tracheal intubation, supplemented with topical anesthesia of lidocaine (2 mg.kg-1), were attempted. " 10/01/1991 - "Overnight slight loss of consciousness associated with severe cardiac arrhythmia (bigeminia ventricular extra-systole) needed admission to the intensive care unit and intravenous lignocaine for two days. " 01/01/2007 - "All patients received topical lidocaine 2% and propofol by plasma target control infusion (initial target concentration 3 microg ml(-1), then adjusted to maintain loss of consciousness without apnoea). " 09/01/2005 - "In a previous randomized trial, sotalol was superior to lignocaine for acute termination of ventricular tachycardia not causing loss of consciousness. " 05/01/2005 - "After a test dose of 3 mL 1.5% lidocaine with 15 microg of epinephrine and 2 minutes after a bolus of 5 mL of 0.25% bupivacaine, there was a rapid onset of massive subdural anesthesia with a loss of consciousness, respiratory arrest, and absent pulses. "
6.	KetamineFDA LinkGeneric 10/01/2015 - "At high doses, however, ketamine also acts at non-NMDAR sites, produces loss of consciousness, and the transient disappearance of the HFO. " 09/01/2015 - "After loss of consciousness, ketamine was administered to the group SK in the form of a 0.5-mg/kg intravenous bolus. " 01/01/2012 - "Ketamine is a respiratory stimulant that abolishes the coupling between loss-of-consciousness and upper airway dilator muscle dysfunction in a wide dose-range. " 01/01/2012 - "Ketamine activates breathing and abolishes the coupling between loss of consciousness and upper airway dilator muscle dysfunction." 01/01/2010 - "Temporal dynamics of distinct CA1 cell populations during unconscious state induced by ketamine."
7.	Midazolam (Versed)FDA LinkGeneric 08/01/2014 - "To explore the effect of hepatic function on loss of consciousness (LOC) and bispectral index (BIS) during sedation with midazolam (MDZ). " 08/01/2014 - "Effect of hepatic function on the EC50 of midazolam and the BIS50 at the time of loss of consciousness." 05/01/2011 - "Midazolam-induced loss of consciousness is associated with remarkable suppression of cortico-cortical propagation of evoked currents. " 02/09/2010 - "Breakdown in cortical effective connectivity during midazolam-induced loss of consciousness." 04/01/1999 - "We conclude that loss of consciousness after midazolam was associated with an increase in mean Nb latency."
8.	Hypnotics and Sedatives (Sedatives)IBA 10/01/1970 - "Interaction of alcohol with sedatives and tranquillisers (a study of blood levels at loss of consciousness following rapid infusion)." 08/01/2004 - "A technical review of rapid sequence induction of anesthesia is presented, emphasizing the rational use of hypnotics, opioids and neuromuscular blockers (NMB) to shorten the period between loss of consciousness and correct tracheal tube positioning, that is, shorten the period of highest risk for aspiration while maintaining excellent intubation conditions. " 02/01/2015 - "The list of level A recommendations includes: 1) use of IV acetaminophen for opioid sparing properties and reduction of opioid related adverse events; 2) ketamine-midazolam combination preferred over fentanyl-midazolam fentanyl-propofol in pediatric patients; 3) boluses of ketamine IV (particularly in the population under the age of 2 years and over the age of 13) can lead to impairment of the upper airways, including the onset of laryngospasm, requiring specific expertise and skills for administration; 4) the use of ketamine increases the potential risk of psychomotor agitation, which can happen in up to 30% of adult patients (this peculiar side effect can be significantly reduced by concomitant systemic use of benzodiazepines); 5) for shoulder dislocations and fractures of the upper limbs, the performance of brachial plexus block reduces the time spent in ED compared to sedation; 6) pain relief and the use of opioids in patients with acute abdominal pain do not increase the risk of error in the diagnostic and therapeutic pathway in adults; 7) in newborns, the administration of sucrose reduces behavioural responses to blood sampling from a heel puncture; 8) in newborns, breastfeeding or formula feeding during the procedure reduces the measures of distress; 9) in pediatric patients, non-pharmacological techniques such as distraction, hypnosis and cognitive-behavioural interventions reduce procedural pain caused by the use of needles; 10) in pediatric patients, preventive application of eutectic mixtures of prilocaine and lidocaine allows arterial and venous samples to be taken in optimum conditions; 11) in pediatric patients, the combination of hypnotics (midazolam) and N2O is effective for procedural pain, but may be accompanied by loss of consciousness. "
9.	Opioid Analgesics (Opioids)IBA 08/01/2004 - "A technical review of rapid sequence induction of anesthesia is presented, emphasizing the rational use of hypnotics, opioids and neuromuscular blockers (NMB) to shorten the period between loss of consciousness and correct tracheal tube positioning, that is, shorten the period of highest risk for aspiration while maintaining excellent intubation conditions. " 07/01/2003 - "Induction with sevoflurane in nitrous oxide and oxygen leads to fast loss of consciousness and provides ideal conditions for managing the airway without supplemental opioids or muscle relaxants. " 10/01/2014 - "The cases demonstrate that MT-45, like other opioids, can induce potentially life threatening respiratory depression and loss of consciousness in users and that symptoms are usually reversed by standard doses of the opioid receptor antagonist naloxone. " 10/01/2010 - "We conclude that induction with sevoflurane in nitrous oxide and oxygen leads to fast loss of consciousness and provides ideal conditions for managing the airway without supplemental opioids or muscle relaxants with haemodynamic stability and is therefore a reasonable alternative to halothane for paediatric patients." 02/01/2015 - "The list of level A recommendations includes: 1) use of IV acetaminophen for opioid sparing properties and reduction of opioid related adverse events; 2) ketamine-midazolam combination preferred over fentanyl-midazolam fentanyl-propofol in pediatric patients; 3) boluses of ketamine IV (particularly in the population under the age of 2 years and over the age of 13) can lead to impairment of the upper airways, including the onset of laryngospasm, requiring specific expertise and skills for administration; 4) the use of ketamine increases the potential risk of psychomotor agitation, which can happen in up to 30% of adult patients (this peculiar side effect can be significantly reduced by concomitant systemic use of benzodiazepines); 5) for shoulder dislocations and fractures of the upper limbs, the performance of brachial plexus block reduces the time spent in ED compared to sedation; 6) pain relief and the use of opioids in patients with acute abdominal pain do not increase the risk of error in the diagnostic and therapeutic pathway in adults; 7) in newborns, the administration of sucrose reduces behavioural responses to blood sampling from a heel puncture; 8) in newborns, breastfeeding or formula feeding during the procedure reduces the measures of distress; 9) in pediatric patients, non-pharmacological techniques such as distraction, hypnosis and cognitive-behavioural interventions reduce procedural pain caused by the use of needles; 10) in pediatric patients, preventive application of eutectic mixtures of prilocaine and lidocaine allows arterial and venous samples to be taken in optimum conditions; 11) in pediatric patients, the combination of hypnotics (midazolam) and N2O is effective for procedural pain, but may be accompanied by loss of consciousness. "
10.	Pregnanolone (Allopregnanolone)IBA 12/01/1994 - "Eltanolone 4 mg ml-1 was administered at a rate of 300 ml h-1 (group 1), 600 ml h-1 (group 2) or 1200 ml h-1 (group 3) until loss of consciousness, as judged by loss of verbal contact with the patient. " 04/01/1992 - "Loss of eyelash reflex is not a good end point for assessment of loss of consciousness following pregnanolone." 10/01/1998 - "We investigated whether fentanyl decreases the serum concentrations of the steroid anesthetic eltanolone effective in producing loss of consciousness in 50% of patients (EC50induction) and in preventing movement at skin incision in 50% of patients (EC50incision). " 10/01/1998 - "Fentanyl reduced the serum concentration of eltanolone required to produce loss of consciousness and the target concentration of eltanolone required to prevent movement to skin incision. " 10/01/1998 - "Dixon analysis (43 patients) produced an eltanolone ET50incision of 2288 ng/mL at fentanyl targets of 0.5 ng/mL, 754 ng/mL at 1.5 ng/mL, 735 ng/mL at 3.0 ng/mL, and 645 ng/mL at 4.5 ng/mL. Fentanyl reduced the serum concentration of eltanolone required to produce loss of consciousness and the target concentration of eltanolone required to prevent movement to skin incision. "

Therapies and Procedures

1.	Anesthesia 01/01/2016 - "Decoupled temporal variability and signal synchronization of spontaneous brain activity in loss of consciousness: An fMRI study in anesthesia." 01/01/2016 - "The molecular agents that induce loss of consciousness during anesthesia are classically believed to act by binding to cognate transmembrane receptors widely distributed in the CNS and critically suppressing local processing and network connectivity. " 01/01/2016 - "To evaluate this hypothesis and understand how these interactions are modulated by state changes, we analyzed electrophysiological recordings in humans at different nodes of one well-studied brain network: the basal ganglia-thalamocortical loops of the motor system during loss of consciousness induced by anesthesia. " 09/04/2015 - "As p decreases, a steep divergence of the transmitted signal from the original was observed, along with a loss of signal synchrony and a sharp increase in information entropy in a critical manner; this resembles the precipitous loss of consciousness during anesthesia. " 01/01/2014 - "Modeling anesthesia as a moderate reduction in gap-junction interneuronal coupling, they predict an unconscious state signposted by emergent low-frequency oscillations with chaotic dynamics in space and time. "
2.	Craniotomy 01/01/2014 - "We are reporting the case of a 56-year-old woman who developed loss of consciousness during awake craniotomy. " 01/01/2014 - "A case of loss of consciousness with contralateral acute subdural haematoma during awake craniotomy." 11/01/2010 - "In the in vivo impact experiments, pigs in an unconscious state were exposed through craniotomy, and their exposed brains were hit with a ram at a low speed of 3.3 m/s and a high speed of 7.2 m/s, respectively. " 10/01/2013 - "Neuroanesthesia for craniotomy should be aimed to ensure intraoperative loss of consciousness (unless awake craniotomy is the selected anesthesiological approach), pain control and an uneventful postoperative recovery, but should also be addressed to manipulate physiological variables including cerebral blood flow and to obtain optimal surgical exposure." 09/01/2013 - "However, we present a very rare case of a 53-year-old woman with a right temporal mass that turned out to be a MS plaque, who deteriorated within hours (brain herniation with loss of consciousness and unilateral mydriasis) and required an emergency craniotomy. "
3.	Hypnosis (Mesmerism) 01/01/2012 - "Of these, the mechanism of hypnosis, or loss of consciousness, has been the most elusive, yet a fascinating problem. " 11/01/2014 - "This document reviews the literature on local brain manipulation of general anesthesia in animals, focusing on behavioral and electrographic effects related to hypnosis or loss of consciousness. " 11/01/2011 - "Anesthesia describes a complex state composed of immobility, amnesia, hypnosis (sleep or loss of consciousness), analgesia, and muscle relaxation. " 08/01/2012 - "Decreased activity of these cells may be pivotal in the ability of general anesthetics to induce loss of consciousness and promote sleep (hypnosis). " 03/01/2001 - "For maintenance of hypnosis, propofol or desflurane were used in concentrations to ensure loss of consciousness, lack of awareness, and maintenance of heart rate and blood pressure within +/- 25% of initial values. "
4.	Defibrillators (Defibrillator) 10/26/2000 - "Automated external defibrillators were used for 200 patients (191 on the aircraft and 9 in the terminal), including 99 with documented loss of consciousness. " 11/01/1987 - "In patients whose presenting arrhythmias did not result in loss of consciousness (group C), initial treatment with the defibrillator appears unnecessary." 11/01/1987 - "The defibrillator is highly effective in preventing sudden death in patients whose presenting arrhythmias caused loss of consciousness (group A). " 02/02/1996 - "One patient had a fatal car accident, unrelated to loss of consciousness or defibrillator shock. " 11/01/1987 - "Before February 1985, patients received treatment with the defibrillator and amiodarone if they presented with loss of consciousness (group A) and amiodarone alone if they did not lose consciousness (group C). "
5.	Hyperbaric Oxygenation 08/15/2006 - "Since brain histology changes cannot be studied in CO-poisoned patients we evaluated the efficacy of normobaric and hyperbaric oxygen therapy in preventing brain cell injury in CO-poisoned animals without loss of consciousness. " 08/15/2006 - "In conclusion, immediate normobaric and hyperbaric oxygen therapy equally prevents hippocampal cell injury in CO-poisoned rats without loss of consciousness." 11/01/1994 - "Criteria for hyperbaric oxygen therapy were blood CO of more than 20%, loss of consciousness, pregnancy, or signs of cardiac injury. "