Unconsciousness

Examples include unconsciousness, disorders involving the osmostat or the thirst center (e.g., post-obit a subarachnoid hemorrhage), inability to communicate the desire for water (e.g., infants, a patient with a stroke), inability to obtain water (due east.g., inability to move), recurrent vomiting, or mechanical obstacle of the upper gastrointestinal tract (e.g., an esophageal tumor).

From: Fluid, Electrolyte and Acid-Base of operations Physiology (5th Edition) , 2017

Unconsciousness

Stanley F. Malamed DDS , ... Daniel L. OrrII DDS, MS (ANES), PHD, JD, Physician , in Medical Emergencies in the Dental Office (7th Edition), 2015

Recognize Unconsciousness
(Lack of response to sensory stimulation)
↓
Discontinue dental treatment
↓
Activate function emergency team
↓
P—Identify unconscious victim in supine position with feet elevated
↓
C →A → B—Quickly appraise for spontaneous breathing and palpable pulse (carotid) for not more than x seconds.
In absence of pulse chest compression is immediately started (see Chapter xxx)
In presence of palpable pulse, airway and breathing are performed every bit needed
↓
Actuate emergency medical services if recovery of consciousness is not immediate
↓
D—Provide definitive care as needed

Read full chapter

URL:

https://world wide web.sciencedirect.com/scientific discipline/article/pii/B9780323171229000056

Unconsciousness

Stanley F. Malamed DDS , ... Daniel L. Orr2 DDS, MS (ANES), PHD, JD, MD , in Medical Emergencies in the Dental Office (Seventh Edition), 2015

Heart charge per unit and blood pressure

In most instances of unconsciousness hypotension is evident. Normally, every bit claret force per unit area falls (hypotension) the heart rate increases (tachycardia). As an case, claret pressure level may be quite low during a hypoglycemic or hyperglycemic episode while the heart, attempting to recoup for this autumn in claret force per unit area, accelerates its charge per unit of contraction. However, vasodepressor syncope, postural hypotension, and cerebrovascular accident are exceptions to these changes in vital signs.

In vasodepressor syncope, both the claret pressure and the centre rate decrease. A heart rate of 50 beats per infinitesimal or less is common during the syncopal phase of vasodepressor syncope. The centre rate during postural hypotension remains at approximately its baseline level, although the blood pressure drops precipitously.

The pulse, equally monitored in the radial, brachial, or carotid artery, is normally described as "weak" or "thready" in persons whose blood pressures are low. On the other hand, the claret pressure in the case of a hemorrhagic cerebrovascular accident may exist elevated significantly (systolic pressure elevated more than diastolic pressure) and the pulse described as "strong" or "bounding."

In cases of clinically significant dysrhythmias, the heart rate may be variable (bradycardic, tachycardic, or baseline), merely the functional output of the heart has decreased to a level at which it adversely affects peripheral perfusion. Blood force per unit area is almost always depressed in such situations (Tabular array 9-1).

Read total chapter

URL:

https://www.sciencedirect.com/scientific discipline/commodity/pii/B9780323171229000093

Disorders of Consciousness

Nicole 1000. Cuff , Bernard J. Baars , in Fundamentals of Cerebral Neuroscience (Second Edition), 2018

ii.ii Reversible Unconsciousness – Anesthesia

The unconsciousness produced by anesthesia is entirely different than unconsciousness experienced during normal SWS. Anesthesia contains many substances that work together to produce the controlled unconsciousness of a patient, including agents that produce a brief amnesia or memory loss, analgesia that provide pain relief, reflex suppression that cause temporary immobilization or paralysis, and agents that produce a hypnotic land to reduce awareness. How does anesthesia cause the brain to fall into unconsciousness? Just put, anesthesia alters the flow of sodium molecules into the cell membranes of neurons, blocking the product of activeness potentials. Nether anesthesia, neural activity throughout the brain is reduced, in sharp dissimilarity to the brain activity in SWS. Fig. 13.3 shows this outcome on awareness and wakefulness in a schematic form, with the both the level of awareness and the level of wakefulness reduced equally compared to deep sleep.

Figure xiii.three. The same effigy as Fig. 13.2, in this case the states of anesthesia-sedated and coma are shown with depression levels of sensation and wakefulness (circled in red).

 Source: Laureys (2005).

Unconsciousness caused by anesthesia is reversed by reducing the anesthesia and arousing the patient. As the patient arouses, both the sensation and wakefulness levels increase until full wakefulness occurs. Depending on the type and elapsing of anesthesia, this waking procedure tin can take minutes to hours, again in sharp dissimilarity to moving from SWS into higher sleep stages in normal sleep.

Read full affiliate

URL:

https://www.sciencedirect.com/science/article/pii/B9780128038130000131

Diabetes Mellitus

James W. Little DMD, MS , ... Nelson Fifty. Rhodus DMD, MPH , in Fiddling and Falace'due south Dental Management of the Medically Compromised Patient (8th Edition), 2013

Severe Stage

Complete unconsciousness with or without tonic or clonic muscular movements occurs during the severe stage. Most of these reactions take place during slumber, after the get-go two stages have gone unrecognized. Onset of this stage also may occur after do or later on the ingestion of alcohol, if earlier signs have been ignored. Sweating, pallor, rapid and thready pulse, hypotension, and hypothermia may exist present.

The reaction to excessive insulin can exist corrected past giving the patient sweetened fruit juice or anything with sugar in information technology (cake icing). Patients in the severe stage (unconsciousness) are all-time treated with an intravenous glucose solution; glucagon or epinephrine may be used for transient relief.

Read full affiliate

URL:

https://www.sciencedirect.com/science/article/pii/B9780323080286000142

Syncope

Myung K. Park MD, FAAP, FACC , in Pediatric Cardiology for Practitioners (Fifth Edition), 2008

Exercise-Related Syncope

Sudden unconsciousness that occurs during or after strenuous physical activities or sports may signal an organic cause such equally cardiopulmonary diseases. However, in most cases, exercise-related syncope is not an indicator of serious underlying cardiopulmonary or metabolic disease. It is more often due to a combination of venous pooling in vasodilated leg muscles, inadequate hydration, and high ambient temperature. Hyperventilation with hypocapnia (with tingling or numbness of extremities) secondary to strenuous activities may likewise cause syncope. To preclude venous pooling, athletes should proceed moving later running competitions.

Read total chapter

URL:

https://www.sciencedirect.com/scientific discipline/article/pii/B9780323046367500423

Traumatic Skull and Facial Fractures

Peter A. Chiarelli , ... Amy Lee , in Principles of Neurological Surgery (Quaternary Edition), 2018

Brain Injury

Coma or unconsciousness should not prevent or delay the treatment of facial fractures; many patients with facial fractures are in a coma for several weeks before waking up. In patients with maxillofacial fractures, neurologic deficits from frontal lobe symptoms may exist subtle or absent despite contusions imaged on brain CT scans. Confusion, somnolence, personality alter, irritability, and difficulty in thinking are some of the milder symptoms of frontal brain contusion. In patients with Glasgow Coma Scale scores of xiv or lower, especially when traumatic encephalon abnormality is visualized on CT scan, an intracranial force per unit area monitoring device may be employed in those patients who crave anesthesia. An intracranial pressure (ICP) monitor or intracranial ventricular pressure monitor is used in the operating room during the facial repair, thus assuasive optimal modification of the anesthesia and if necessary CSF drainage in patients in whom multiple injuries require early surgical intervention.

Read full affiliate

URL:

https://www.sciencedirect.com/science/article/pii/B9780323431408000287

Diagnostic Peritoneal Lavage and the Focused Assessment with Sonography in Trauma

Gerald R. FortunaJr. Physician , in The Mont Reid Surgical Handbook (Sixth Edition), 2008

II. INDICATIONS FOR DIAGNOSTIC PERITONEAL LAVAGE

A. Nearly USEFUL

In blunt intestinal trauma and manifestations of hypovolemia—hypotension and tachycardia

1.

Unconscious patients with concerns of a potential abdominal injury

2.

Patients with high-energy injuries, suspected intraabdominal injury, and nonspecific abdominal concrete findings

iii.

Presence of multiple injuries with unexplained shock

4.

Patients with major noncontiguous or thoracoabdominal injuries

5.

Patients with spinal string injuries

6.

Intoxicated patients with suspected intraabdominal injuries

vii.

Patients with suspected intraabdominal injuries but equivocal diagnostic testing who are being transferred to the operating room with general anesthesia where series examinations and monitoring are not possible

B. EQUIVOCAL Intestinal FINDINGS

Often a consequence of lower rib fractures, pelvic fractures, and lumbar spine fractures

i.

Intestinal findings such as localized tenderness and guarding

2.

Low rib fractures, particularly on left side

C. PENETRATING TRAUMA

With questionable involvement of the peritoneal cavity is controversial and has been debated extensively in the trauma literature

D. CONTROVERSIAL INDICATIONS FOR DPL, CT, OR BOTH

one.

Penetrating injury to surrounding areas

a.

Lower chest—beneath nipples or 4th intercostal space

(1)

In this situation, the patient is at risk for thoracoabdominal injuries depending on the trajectory of the projectile. In an unstable patient, a positive DPL could assist dictate which cavity is initially explored.

b.

Flank

c.

Buttocks and perineum

2.

Stab wounds or depression-caliber gunshot wounds with no significant physical findings. DPL in this setting may be helpful in identifying intraabdominal injury. Could also consider laparoscopy.

Read full chapter

URL:

https://world wide web.sciencedirect.com/science/article/pii/B9781416048954500883

Airway management and acute airway obstacle

Gavin M Joynt , Gordon YS Choi , in Oh's Intensive Care Manual (Seventh Edition), 2014

Oro- and nasopharyngeal airways

In the unconscious patient, functional obstacle may occur because of loss of muscular tone and inspiratory airway narrowing at the soft palate, epiglottis and natural language base. An oropharyngeal airway device may plant an adequate airway for spontaneous or bag-mask ventilation when proper caput positioning is insufficient. It is inserted with the concavity facing the palate and then rotated 180° into the proper position every bit information technology is avant-garde. Complications include mucosal trauma, worsening the obstruction by pressing the epiglottis against the laryngeal outlet if the natural language displaces posteriorly, and occasionally laryngospasm. The following sizes (length from flange to tip) are recommended: large adult: 100 mm (Guedel size 5), medium adult: xc mm (Guedel size iv), and small adult: 80 mm (Guedel size three).

A nasopharyngeal airway is a soft rubber or plastic tube inserted into the nostril and advanced along the floor of the nose (in the direction of the occiput). It is better tolerated by semiconscious patients than the oropharyngeal airway. Complications include epistaxis, aspiration and, rarely, laryngospasm and oesophageal placement.

Read full chapter

URL:

https://www.sciencedirect.com/scientific discipline/article/pii/B9780702047626000291

Cardiac Arrest and Cardiopulmonary Resuscitation

Wanchun Tang , Max Harry Weil , in Critical Care Medicine (Third Edition), 2008

Airway and Ventilation

In an unconscious patient, the normal muscle tone that typically maintains the jaw in an elevated position is lost. The natural language is probable to descend into the pharynx and align itself with the epiglottis, obstructing the airway. 30 When the lower jaw is physically lifted and displaced anteriorly, the tongue is lifted abroad from the pharynx, artificially restoring an open up airway. These interventions are termed head tilt–chin elevator and jaw thrust. Airway adjuncts, specifically oropharyngeal and nasopharyngeal airways, may exist used to preclude mechanical descent of the tongue over the airway. 31

Early on endotracheal intubation is more often than not preferred because it secures the patency of the airway and isolates it from the gastrointestinal tract. It reduces the take chances of aspiration and greatly facilitates suctioning of the airways for removal of secretions or foreign cloth. Intubation also secures airtight closure when airway resistance is increased, and mechanical insufflation is required to evangelize titrated tidal volumes nether weather condition when excesses of airway pressure must be avoided. 32 Devices that may be inserted without visualization of the trachea have gained some popularity, particularly the esophageal obturator airway, 33 the esophageal gastric tube airway, 34 the pharyngotracheal lumen airway, 35 the esophageal-tracheal tube, 36 and the laryngeal mask. 37 Current experience favors the laryngeal mask airway. 38

These devices have not allowed for consistently effective positive-pressure ventilation, nevertheless, and their employ in most instances has been associated with a large incidence of iatrogenic complications. Rescue animate is accomplished by mouth-to-mouth, mouth-to-nose, or, occasionally, mouth-to-stoma breathing. 31,39 Alternatively, a barrier device may be used, which incorporates a facemask and shields. twoscore Although early endotracheal intubation has remained the favored intervention, 41 there is increasing prove that intermission of precordial compression and defibrillation for initial endotracheal intubation may compromise outcome. We recommend use of an oropharyngeal airway or, preferably, the laryngeal mask as a better option during the initial v to seven minutes of CPR. Whatever barrier devices are used, they should be elementary, well-fitting, fabricated of transparent material to let detection of gastric regurgitation, and inexpensive.

Barrier devices are reassuring to rescue personnel because of the perceived risks of transmission of human being immunodeficiency virus or hepatitis B or C, 42 merely there is no documented example in which such viruses have been transmitted during the course of mouth-to-rima oris or mouth-to-nose rescue breathing. 43 Bag-valve devices are ideal for the trained rescuer. These include a self-inflating pocketbook with a nonrebreathing valve and a universal adapter. The adapter is used in conjunction with a facemask, laryngeal mask, or endotracheal tube. When a facemask is used, there is a serious risk of overenthusiastic "bagging." This causes gaseous distention of the stomach and proximal intestine, which compromises constructive ventilation and greatly increases the hazard of vomiting and aspiration. Finally, rescue animate by trained rescuers in the field is finer supplied by gas-powered, manually triggered positive-pressure devices and transport ventilators. 44

Ventilation is conventionally maintained with 10 to 12 breaths per minute. In that location is increasing evidence, however, that frequency and tidal volumes may exist essentially reduced without compromise of outcome. 45–47 The inspired gas mixture supplied by purse-valve devices or ventilators may exist either room air or an oxygen mixture. Increases in fraction of inspired oxygen may be of substantial benefit. Objective bear witness that early intermittent positive-force per unit area ventilation improves outcome is uncertain, however. These issues, together with the optimal oxygen concentrations of inspired gas mixture during CPR, are currently nether active reinvestigation. 45–48 We caution against vigorous bag-valve ventilation. With greatly reduced pulmonary blood menstruation, tidal volumes that are one half of conventional values for anesthetized patients suffice.

Read full chapter

URL:

https://www.sciencedirect.com/scientific discipline/article/pii/B9780323048415500030

Intravenous coldhearted agents

Misha A Perouansky , Hugh C HemmingsJr, in Foundations of Anesthesia (2nd Edition), 2006

ANESTHETIC NEUROTOXICITY

Anesthetic-induced unconsciousness has been traditionally regarded as a fully reversible drug-induced status without any intrinsic sick effects on the central nervous system. Recent laboratory reports have begun to challenge this complacent assumption. Based on the observation that drugs that increment GABA A-ergic inhibition and/or inhibit NMDA receptors (e.g. ethanol) induce widespread apoptosis in the developing rodent brain, recent studies report widespread neurodegeneration and persistent learning deficits in rats exposed in the early on postnatal menses to anesthetic doses of midazolam, nitrous oxide, and isoflurane. The almost severe effects were induced by co-administration of all 3 drugs. The importance of these findings for clinical practice is unclear at present.

Read full affiliate

URL:

https://www.sciencedirect.com/science/commodity/pii/B9780323037075500310