hemorrhagic shock, C-spine, anaphylaxis Flashcards
what is Morrison’s pouch
what does it indicate if free fluid is found here?
hepatorenal space
indicates intra-abdominal hemorrhage secondary to solid organ injury
algorithm for management of trauma pt
ABCs (ask pt name and look for tracheal deviation)
-IV access, begin rapid infusion NS
cardiac monitor, supplemental oxygen
-control obvious hemorrhage with direct pressure
-FAST exam, Chest, Pelvis/C-spine XR, CT scan
-establish definitive hemostasis (OR/IR), ongoing fluid/blood resuscitation
how to determine trauma pt’s level of functioning and get a rapid/relevant hx
GCS, the "AMPLE" hx guide Allergies Meds PMHx (significant) Last meal Event recall (leading up to accident)
FAST exam looks for free fluid in ?
Morison pouch, splenorenal and supra-splenic space, pelvis, and pericardial space
ultrasound can also be used for rapid identification of ?
pneumothorax, hemothorax, cardiac activity, and central line placement if needed
Shock is divided into three stages
Compensated (SNS–>^HR, contractability, vasoconstriction; angiotensin–>fluid retention)
Progressive (arterial pressure falls)
Irreversible
The normal manifestations of shock do not apply to ?
pregnant women, athletes, and individuals with altered autonomic nervous systems (older patients, those taking B-blockers)
the 1st and 2nd most common causes of death in trauma pts
TBI then hemorrhagic shock
ATLS Classification of Hemorrhage
http://casefiles.mhmedical.com.mwu.idm.oclc.org/ViewLarge.aspx?figid=104716039&gbosContainerID=70&gbosid=218344
tibial or humeral fractures can be associated with ? of blood loss, whereas femur fractures can be associated with up to ? of blood in the thigh. Pelvic fractures may result in ?
750 mL (1.5 units of blood) 1500 mL (3 units of blood) even more blood loss—up to several liters can be lost into a retroperitoneal hematoma
HCT/Hbg in acute hemorrhage?
may or may not be decreased as they measure concentration, not actual amounts
hemorrhagic shock results in metabolic acidosis..good laboratory measures to get?
lactate and base deficit levels
- however, not true representations of tissue hypoxia as they are global indices of tissue perfusion and normal values may mask areas of under perfusion
- but normalization within 24 hrs is a good prognostic indicator of survival
lactate is not a reliable value in what patients?
patients with liver dysfunction (hepatically metabolized)
What is considered the best clinical estimate of preload?
Left-ventricular end-diastolic volume
via pulmonary artery catheter (PAC)
recent alternatives to PAC for measuring preload
ultrasound to assess intravascular volume status by examining the respiratory variation of the IVC (more variation signifying low intravascular volume), or by calculation a ratio of the diameter of the IVC to the aorta
fluid resuscitation in hemorrhagic shock
NS or LR, give 3 mL replacement for each 1 mL of blood loss: for each 1 L infused, 300 mL stays in the intravascular space while the remainder leaks into the interstitial space
A blood transfusion is indicated if ?
the patient persists in shock despite the rapid infusion of 2 to 3 L of crystalloid solution, or if the patient has had such severe blood loss that cardiovascular collapse is imminent (if cannot type/cross match, O- blood for females, O+ for males)
Should non-blood product colloid solutions such as ? be used in the acute setting?
albumin and hetastarch or dextran
they are not superior to crystalloid replacement in the acute setting and have the potential for large fluid shifts and pulmonary or bowel wall edema
what may be used to retain fluid in the intravascular space in trauma situations with no access to blood products, such as in military settings?
Hypertonic solutions such as 7.5% saline
why permissive hypotension in hemorrhagic shock?
artificially increased BP by aggressive fluid resuscitation may disrupt endogenous clot formation and promote further bleeding
-fluids often cooler than body temp, which may result in hypothermia
Patients in whom permissive hypotension should not be practiced
patients with TBIs who require maintenance of their cerebral perfusion pressure; patients with a history of HTN, CHF, CAD, in whom hypotension will be poorly tolerated and may produce other medical problems such as stroke or MI
BP at rest typically does not decrease until class ?hemorrhagic shock, when ? of blood is lost
III
1500 to 2000 mL (30%-40% of blood volume)
Class I hemorrhagic shock is well compensated associated with ? EBL and what changes in vitals?
750 mL EBL or less, with no effect on blood pressure and minimal effect on heart rate
Class II shock is associated with ? EBL, is associated with what vital changes?
750 to 1500 mL
tachycardia but normal BP at rest, and low urine output
evaluation of neck pain
Either three views of the C-spine (AP, lateral, and odontoid views) or CT of the cervical spine (CT preferred)
if no bony fractures or dislocation and midline tenderness persists, then obtain flexion/extension x-rays or MRI of the C-spine to help differentiate ligamentous injury/spinal instability from soft tissue contusion
C-spine radiography is indicated for asymptomatic trauma patients unless they meet all of the following criteria (Nexus low-risk criteria)
(1) No posterior midline cervical tenderness
(2) No evidence intoxication
(3) Normal level of alertness
(4) No focal neurologic deficits
(5) No painful distracting injuries
(Canadian C-spine rule (CCR) even better)
anterior vs posterior vs central cord injuries
anterior: can cause complete motor paralysis, loss of pain/temp
posterior: (Brown-Sequard) causes paralysis, loss of vibratory sensation and proprioception ipsilaterally and loss of pain/temp sensations contralaterally
central: produced by injuries to the corticospinal tract, which produces great UE weakness in comparison to the LE
among patients presenting with intact neurological status to the ED, the incidence of acute C-spine fracture or spinal injury is ?
less than 1%
patient classifications in C-spine injuries
asymptomatic: CCR
temporarily non-assessable (intox/distracting injuries): reassess or tx as obtunded
symptomatic (neck pain, midline tenderness, or neuro s/s): tx as above (neck pain)
obtunded: CT of the C-spine
Canadian C-spine Rule (CCR)
http://casefiles.mhmedical.com.mwu.idm.oclc.org/ViewLarge.aspx?figid=141651404&gbosContainerID=70&gbosid=218346
From C1 to C7, nerve root exit ? the level of the vertebrae, and from C8 and lower, the nerve roots exit ? the vertebrae
above
below
most reliable way to detect hypoventilation is by
PaCO2 measurements on ABG
accessory muscles of resp. innervated via thoracics
In SCI pts, good to maintain MAP of ? to maximize spinal cord perfusion
If needed, patients with isolated spinal cord injuries may benefit from initiation of ? Bradycardia associated with neurogenic shock can be addressed with ?
85 to 90 mm Hg
vassopressors such as dopamines or norepinephrine
atropine
steroids in SCIs?
- only some benefits for individuals when the treatment was initiated within 3 hours of the injury
- increased rates of sepsis and other steroid complications
- should not be initiated for patients in the ED prior to discussions with the trauma and/or spine specialists who will ultimately manage the patient after ED discharge
Orthopedic injuries to the upper extremities are categorized by ?
the bone, location (proximal, midshaft, or distal), presence or absence of joint involvement, degree of angulation, extent of comminution, and whether the fracture is open or closed
fractures that involve both the ulna and radius are considered?
while Injuries that involve only one of the two bones are generally stable and are treated by ?
unstable fractures and are less amendable to closed fixations; therefore, many of these fractures are managed by ORIF
closed manipulation, cast immobilization under conscious sedation or US-guided regional nerve blocks
most commonly encountered distal radial fracture: fracture of the distal radial metaphysic with dorsal displacement of the distal fragment
Colles-Pouteau fracture
The decision to treat patients by closed reduction and fixation versus operative reduction and fixation are determined by ?
the degree of alignment, age, and functional status of the patients
Distal radius fractures occur most commonly in who?
bimodal pattern with peaks in late childhood and after the sixth decade of life
management of anaphylaxis
airway management and early administration of epinephrine
volume resuscitation with crystalloid, nebulized beta agonists (dilation), nebulized racemic epinephrine (decrease laryngeal edema), corticosteroids (blunt immune response), antihistamines (including H2 blockers: Diphenhydramine and ranitidine), and removal of any remaining antigen (ie, the bee stinger)
Patients may lose over ? of their blood volume to extravasation in the first ten minutes of their allergic reaction
30%
Decreased vascular tone and increased capillary permeability lead to cardiovascular compromise and hypotension
cytokines involved in anaphylaxis
Leukotriene C4, prostaglandin D2, histamine, and tryptase
Elevated tryptase levels confirm the diagnosis
symptoms of anaphylaxis
angioedema, urticaria, erythema, and pruritus
hypotension and tachycardia
bronchospasm and bronchorrhea, edema in the URT
severe: nausea, cramping, and diarrhea
how does Epinephrine help in anaphylaxis
acts as a pressor for hemodynamic support, a bronchodilator to relieve wheezing, as well as to counteract released mediators and prevent their further release
Epi dosing
initially IM: anterior thigh with the more concentrated 1:1000 dose at 0.3 to 0.5 mL every 5 minutes
if no response or CV compromise, IV
IV is more rapid, but take care in elderly and those with CV risk factors
SEs: HTN, tachycardia, dysrhythmias, MI
IV Epi dosing
ampules of epinephrine have 1 mg of medication (1 mL of 1:1000 = 1 mg of medication; 10 mL of 1:100,000 = 1 mg of medication). One method of administration is to place 1 mg (1 ampule) of epinephrine into 1 L of intravenous fluid (equivalent to 1 μg/mL) and infuse to 1 to 4 cc/min (1-4 μg/min)
What has been proposed for individuals on B-blockers in the event they are unresponsive to epinephrine?
glucagon- may overcome hypotension by activating adenyl cyclase independent of the beta receptor
Pitfalls in Anaphylaxis
Failure to recognize the symptoms of anaphylaxis
Underestimating the severity of laryngeal edema and failure to secure the airway early
Reluctance to administer epi early in the course of illness
Forgetting to remove the allergen; eg, the IV drip of PCN or bee stinger
Lack of appropriate patient education
Failure to prescribe an epi auto-injector prior to discharge
