Trauma quiz #2

Trachea

• tube that connects larynx + bifurcates at carina into two mainstem bronchi

• divides into left and right

Bronchi

• supported by cartilage

• gives rise to bronchiole structures supported by smooth muscle

Right mainstem bronchi

often site of aspirated foreign bodies

Bronchioles

• 22 divisions

• give rise to respiratory bronchioles that have limited capacity for gas exchange

Respiratory bronchioles divide into…

alveolar ducts

alveolar ducts terminate into…

alveoli sacs

Alveoli

• sites of primary gas exchange

• surfactant layer to prevent atelectasis

Lung parenchyma

• two pulmonary lobules

• anatomic division of lungs

• further divide into lobes

Pleura

• membranous connective tissue that covers lungs

• parietal

• visceral

Pulmonary respiration occurs in…

lungs

Cellular respiration occurs in…

peripheral capillaries

Ventilation

mechanical process that moves into and out of lungs; necessary for respiration to occur

Respiration

gases exchanged btw red blood cells and alveoli through capillary membranes

Normal expiration

passive process

Inspiration

active process, uses energy

Musculature to change intrathoracic size

• diaphragm

• intercostal accessory muscles

Pulmonary ventilation

depends on changes in pressure within thoracic cavity

Respiratory cycle

coordinated interaction among respiratory system, CNS, and musculoskeletal system

Pulmonary circulation

• respiration requires intact circulatory system

• heart pumps as much blood to lungs as it pumps to peripheral tissues

• right side of heart pumps to lungs via pulmonary artery to lungs for oxygenation and offloading of CO2 waste from tissues

Factors affecting O2 concertation in the blood

• inadequate levels of hemoglobin (anemia, hemorrhage)

• decreased diffusion across pulmonary membrane

• ventilation/perfusion mismatch

Head tilt chin lift

used in non traumatic injuries

modified jaw thrust

• opens the airway without manipulating the C-spine

• method used for trauma patients

How to maintain a patent airway

• air follows path of least resistance

• if airway not maintained wide open, the air will go down the esophagus rather than into lungs

  • positioning

  • move the jaw forward

  • add adjuncts

  • tongue is the enemy

Sniffing position

ear to sternal notch

Sniffing position + ramped position

presumes no concern for cervical injury

Supraglottic

device inserted into the pharynx to secure an open airway and provide ventilation without passing through the vocal chords

Endotracheal tube

Flexible, hollow plastic tube inserted through the mouth or nose into the trachea to maintain an open airway

4 steps for option BVM

1. fully open the airway

2. tight mask seal

3. delivered appropriate volume ± PEEP

4. monitor and readjust as needed

Cormack Lehane Grade 1 v 4

• 4 grade classification system used in anesthesia and emergency medicine to assess the viability of the glottis and laryngeal structures during direct laryngoscopy

• protects intubation difficulty by grading the view from full glottis (1) to no glottis/epiglottis (4)

Mallampati class 1 v 4

• 4 tier assessment tool used to predict the difficulty of endotracheal intubation and assess the risk of obstructive sleep apnea

• evaluates the visibility of anatomical structures (soft palate, uvula, fauces) to estimate space for airway management

Intubation

placing an endotracheal tube in the trachea

Intubation is the most definitive airway: why?

• prevents aspiration

• provides proper gas exchange (O2, CO2)

• ETCO2 monitoring

• hooks up to ventilator for optimized ventilation

Quick crich/trach

a device pre-loaded with a small trach tube and a large bore needle that can puncture the crico-thyroid membrance for an emergency airway

Emergency 5 step cricothyroidotomy

1. Palpate: Identify the cricothyroid membrane (usually between the thyroid and cricoid cartilage).

2. Incise (Skin): Make a vertical incision in the skin over the membrane.

3. Incise (Membrane): Make a horizontal incision through the cricothyroid membrane.

4. Digit/Bougie: Insert a finger or a bougie (a long, flexible tube) into the trachea to maintain the opening.

5. Tube: Insert a cuffed endotracheal tube (usually 6.0 mm or smaller) over the bougie into the trachea.

**fast entry point into trachea

Bougie

thin, flexible, or rigid instrument— often a catheter or rod— used to dilate, guide, or explore tubular structures in the body, such as the esophagus, uretha, or trachea

Direct laryngoscopy

involves looking directly into the patient’s mouth to visualize the vocal cords for intubation

Video laryngoscopy

uses a camera tipped blade to display the airway on a screen

• generally offers better glottic views, improving first-pass success rates, especially in difficult airways

Rapid sequence intubation

• used to paralyze a patient to get an airway

• steps that includes administering a neuromuscular blocking medication in order to facilitate endotracheal intubation

• comprehensive process that should include the highest trained/experienced provider utilizing checklists to optimize first pass success

Foramen magnum

• the only opening of the cranial vault

• too high an ICP will lead to brain herniation

cranial vault is not smooth

this is problematic for any motion of the brain

3 membranes (meninges) — outermost to innermost

1. epidural

2. subdural

3. subarachnoid

Epidural space

• under normal circumstance, it does not exist

• middle meningeal arteries follow grooves in the temporal bone here

Subdural space

space that is spanned with veins (low pressure)

subarachnoid space

gap in which brain vasculature runs

Brainstem

• signal relay between brain and spinal cord

• involuntary responses

• midbrain

• thalamus

• pituitary gland

• pons

• medulla oblongata

Frontal lobe

• motor control (premotor cortex)

• problem solving (prefrontal area)

• speech production (broca’s area)

Temporal lobe

• auditory processing (hearing)

• language (wernicke’s area)

• memory/information retrieval

Parietal lobe

• touch perception (somatosensory cortex)

• body orientation and sensory discrimination

Cerebral Perfusion Pressure (CPP)

• the amount of pressure that is needed to push blood through the cerebral circulation (make sure that there is enough pressure allowing blood flow through the whole brain)

CPP =

MAP (mean arterial pressure) - ICP

As ICP increases…

CPP decreases

• ICP is the main factor that changes CPP

normal intracranial pressure in adults

< 15 mmhg

CNS needs blood supply

• contains glucose, thiamine, and oxygen

• relies on aerobic respiration

• if blood supply stops, unconsciousness follows within 10 seconds and brain death will ensue within 4 to 6 minutes

oxygen

good air plus good breathing

Balanced blood sugar

proper diet plus good digestion

Activation stimulation/input

all sensory input primarily from movement under gravity

primary brain injury

• occurs at time of the injury

• brain bleeds, contusions, and damage to nerve and brain vessels

• neural tissue does not regenerate well, rarely can repair, function of damaged structure of brain is usually permanently lost upon injury

Secondary brain injury

• additional injury that occurs as a result of the progression of an untreated primary injury

• uninjured at the time of the injury

• can happen from hours to weeks after primary injury

• rapid treatment at skilled trauma facilitates gives the best outcomes and prevents worsening secondary injury

Base of the skull fx “basal skull fx”

• unprotected

• spaces weaken structure

• relatively easier to fracture

Sings and symptoms of basal skull fx

1. battle signs

2. raccoon eyes

3. may tear dura

Battle signs (basal skull fx)

• retroarticular ecchymosis

• associated with fracture of auditory canal and lower areas of skull

Racoon eyes (basal skull fx)

• bilateral periorbital ecchymosis

• associated with orbital fractures

may tear dura (basal skull fx)

• permit CSP to drain through an external passageway

  • may mediate rise of ICP

  • evaluate for target or halo sign

Coup

injury at site of impact

Countrecoup

injury at opposite side of impact

Cerebral contusion

• blunt trauma to local brain tissue

• capillary bleeding into brain tissue

• common with blunt head trauma

cerebral contusion S+S

• confusion

• neurologic deficit

  • personality changes

  • vision changes

  • speech changes

• results from coup-countrecoup injury

Epidural hematoma

• bleeding btw dura mater and skull

• involves arteries (middle meningeal artery most common)

• rapid bleeding * and reduction of O2 to tissues

• patients will have a lucid interval

• acute: sudden onset

• time sensitive emergency

Subdural hematoma

• bleeding within meninges

  • beneath dura mater

  • above arachnoid

• slow bleeding

  • superior sagittal sinus

• signs progress over several days

  • slow deterioration of mentation

Intracerebral hemorrhage

• ruptured blood vessel within the brain

• presentation similar to stroke symptoms

• signs and symptoms worsen over time

ICP: cranial volume fixed

• 80% cerebrum, cerebellum, brainstem

• 12% blood vessels and blood

• 8% CSF

ICP: increase in size of one component diminishes size of another

inability to adjust = increased ICP

ICP: compensating for pressure

• compress venous blood vessels

• reduction in free CSF

  • pushed into spinal cord

ICP: Decompensating for pressure

• Increase in ICP

• rise in systemic BP to perfuse brain

  • further increase of ICP

    • dangerous cycle

Cushing’s triad

• increasing systolic blood pressure (hypertension)

• slowing pulse rate (bradycardia)

• irregular respirations (decrease)

Shock

• low BP

• high heart rate

• high respirations

Cheyne stokes

• gradual increases and decreases in respirations with periods of apnea

• caused by increasing intracranial pressure, brain stem injury

Biot’s

• rapid deep respirations (gasps) with short pauses between sets

• caused by spinal meningitis, many CNS causes, head injury

Kussmaul’s

• tachypnea and hyperpnea

• caused by renal failure, metabolic acidosis, diabetic ketoacidosis

Craniotomy

• neurosurgical procedure where a surgeon temporarily removes a piece of the skull (bone flap) to access the brain, often guided by imaging

• used to treat conditions like tumors, aneurysms, blood clots, or swelling

Bolt

• ICP monitor

• a hollow screw inserted through a drilled hole in the skull into the space btw the skull and brain to measure pressure, usually placed in the ICU

• used for quick bedside monitoring of brain swelling in severe trauma

Lvl 1 trauma center

• provides the highest level of comprehensive care from prevention to rehabilitation

• 24/7 in house coverage by trauma surgeons and specialized board certified critical care specialists

Lvl 2 trauma center

• offers similar high level 24/7 emergency and surgical care, but is not required to have the same research or surgical residency programs

• they may transfer cases that exceed their capacity