Trauma Flashcards
What are the tenets of trauma laparotomy?
- Rapid entry via adequate incision
- Control of massive haemorrhage by
- Identification of source
- Packing
- Direct control
- Proximal (source) control
- Identification of injuries
- Control of contamination
- Recontruction as physiological state allows
Discuss the evidence for primary repair versus diversion in traumatic colonic injuries
Dogmatic practice post WWII was diversion for all colonic injuries. That practice has since been challengd with increasing use of primary repair for penetrating colon injuries.
The Cochrane metanalysis of 2003 included ~700 patients with penetrating colonic injury; it demonstrated that total complications, total infectious complications, abdominal infections and wound complications all favored primary repair.
What is Damage Control Surgery?
Damage Control Resuscitation and Damage Control Surgery are a deliberate and pre-emptive set of non-traditional resuscitative and surgical manoeuvers used to reverse the pre-terminal effect of exsanguination, massive injury, and shock.
The primary goal is to temporize injuries with abbreviated surgery to allow for correction of physiological abnormalities.
Describe techniques of reducing intra-cranial pressure
- Hyperventilation; lowering PaCO2 by 1mmHg reduces cerebral blood flow by 3 percent. Aim for levels of 26-30mmHg
- Mannitol according to local protocol
- Hypertonic saline according to local protocol
- High-dose Barbiturate or Propofol for refractory cases
- Surgery - Burr Holes or Craniotomy
*High dose steroids do not improve outcome and are associated with increased mortality!
Discuss the classification of burns by depth
- superficial burn
- painful, dry, not blistered
- will fade on own within 7days, no debridement
- not calculated in TBSA
- superficial partial thickness
- entire epidermis down to BM & no more than upper 1/3 dermis
- bc large no of remaining epithelial cells & good blood supply, v small zone of injury or stasis below burn eschar
- rapid re-epithelialisation in 1-2wks
- wet, often blistered, painful ++, red or white, blanches on pressure
- skin still feels elastic & supple, hair remains attached when pulled
- generally heal w/o SSG, usu within 10-14 days, don’t scar
- deep partial thickness
- entire epidermis down to BM & middle third dermis
- depth of wound has signif risk of conversion; zone of stasis much larger than in SPT injury bc of lower blood flow & greater initial injury to remaining epidermal cells
- re-epithelialisation much slower (2-3wks) due to fewer remaining epidermal cells & a lesser blood supply
- more collagen deposition will occur espec if wound not excised & grafted within 3wks
- often a mixture of wet & dry; the drier it is, the deeper
- sensation variable but still present to touch, though often less painful
- skin texture thicker & more rubbery
- red patches don’t blanche - ‘fixed skin staining’ due to capillary stasis
- hairs will come out readily when pulled
- if not excisedtake 4-6wks to heal & scar badly
- function of a re-epithelialised DPT burn is poor due to fragility of epidermis & rigidity of scar-laden dermis
- full thickness
- entire epidermis & at least 2/3 dermis, leaving v few dermis & epidermal cells to regenerate
- spontaneous healing v slow, over 4wks w usually severe scarring/contracture if not grafted & high risk of infection
- thick, dry, insensate, leathery, usu black or yellow
- thormbosis often visible in surface vessels
- hairs burned off
- may need escharotomies/fasciotomies if full-thickness circumferential
- need early excision and grafting
What are the indications for rib-plating?
- Flail chest with resultant respiratory failure requiring mechanical ventilation is the only indication for rib fracture fixation for which a strong evidence base exists.
- In this population, there are
- reduced intubation times and
- reduced tracheostomy requirements.
Describe the theatre set-up for a trauma
- Experienced assisstant and scrub nurse
- Headlight
- Warm theatre
- Bair Huggers
- Two Yankauer suckers
- 20 large packs
- Cell-saver
- Omnitract
- Vascular set and thoracotomy set
- Fogarty, Haemostatic agents, Shunts
Describe the principles of vascular surgery in trauma
- Prepare the patient for wide access
- Proximal control
- Consider adjuncts such as IR for junctional areas
- Distal control
- Temporise injuries in DCS; shunt
- Repair injury with vascular surgeon
- Adjuncts in vascular surgery
- Fasciotomies
- _Tissue coverag_e of vascular repairs
How is neurological disability grossly calculated?
What is a simplicfication of this score?
With good interobserver reliability and ease of use, the admission Glasgow Coma Scale has been linked to prognosis prediction for a number of conditions, including traumatic brain injury, subarachnoid hemorrhage, and bacterial meningitis.
AVPU is a simplification where:
A = 15
V = 12
P = 8
U = 3
What is the Injury Severity Score?
The Injury Severity Score (ISS) is an anatomical scoring system that provides an overall score for patients with multiple injuries. Each injury is assigned an Abbreviated Injury Scale(AIS) score and is allocated to one of six body regions (Head, Face, Chest, Abdomen, Extremities (including Pelvis), External).
Only the highest AIS score in each body region is used. The 3 most severely injured body regions have their score squared and added together to produce the ISS score.
The ISS score is virtually the only anatomical scoring system in use and correlates linearly with mortality, morbidity, hospital stay and other measures of severity.
Describe the classification of splenic trauma
American Association of Surgical Trauma classifies splenic injury according to degree of subcapsular haematoma, depth of laceration, or size of intraparenchymal haematoma:
Describe the classification of liver trauma
AAST classification is based on degree of subcapsular haematoma, depth of laceration, or size of parenchymal haematoma:
Describe the classification of retroperitoneal trauma
The retroperitoneum is traditionally classified into three zones; a central zone, a (bi)lateral zone, and a pelvic zone
The management algorithm is based on which zone is injured, the mechanism of injury, and whether the haematoma is rapidly expanding.
Zone 1
- Always explored
- Supramesocolic and inframesocolic compartments
Zone 2
- Blunt injury; explore only if haematoma expanding
- Penetrating injury; explore
Zone 3
- Avoid exploration wherever possible; aim for packing and angioembolization
- May require exploration with major vascular injury to lower limb (e.g. no palpable femoral pulse)
Describe the classification of pancreatic trauma
The AAST uses the degree of parenchymal injury as well as the status of the duct to stratify pancreatic trauma:
Describe the classification of duodenal trauma
The AAST classification uses number of haematomas, or the circumferential extent of laceration to stratify duodenal injuries:
Describe the classification of small bowel and colonic trauma
The AAST stratifies both colonic and small bowel injuries according to the degree of circumferential injury
Describe the classification of renal trauma
The AAST classification is based on the depth of parenchymal injury or the degree to which the collecting system or major vasculature is injured:
- Grade I
- haematoma
- subcapsular haematoma and/or parenchymal contusion w/o laceration (operatively non-expanding subcapsular haematoma)
- laceration
- none
- haematoma
- Grade II
- haematoma
- perirenal haematoma confined to Gerota’s fascia (operatively subcapsular haematoma 10-50% surface area or intraparenchymal haematoma <5cm diameter)
- laceration
- renal parenchymal lac ≤1cm depth w/o urinary extravasation
- haematoma
- Grade III
- laceration
- renal parenchymal lac >1cm depth w/o collecting system rupture or urinary extravasation
- vascular
- any injury in presence of a kidney vascular injury or active bleeding contained within Gerota’s fascia
- laceration
- Grade IV
- laceration
- parenchymal lac extending into urinary collecting system w urinary extravasation
- disruption/vascular
- renal pelvis lac and/or complete ureteropelvic disruption
- segmental renal vein or artery injury
- active bleeding beyond Gerota’s fascia into retroperitoneum or peritoneum
- segmental or complete kidney infarction(s) due to vessel thrombosis w/o active bleeding
- laceration
- Grade V
- vascular injury
- main renal artery or vein lac or avulsion of hilum
- devascularised kidney w active bleeding
- disruption
- shattered kidney w loss of identifiable parenchymal anatomy
- vascular injury
Describe the classification of bladder trauma
The AAST system stratifies severity based on size of laceration and whether the injury is extra-peritoneal or intra-peritoneal:
Describe the classification of Pelvic Fractures
The Tile Classification is based on which part/s of the pelvic ring are fractured, and to what degree the pelvis is therefore unstable. Type A fractures are stable, Type B are rotationally unstable, and Type C are both vertically and horizontally unstable.
Describe the classification of blast injury
- Primary blast injury
- Barotrauma from the blast wave
- Gas-containing organs affected (TM, caecum, lungs)
- Secondary blast injury
- Objects strike individual
- Teritiary blast injury
- Individual strikes object
- Traumatic sequelae of persons being thrown causing impact or deceleration injuries
- Quarternary blast injury
- Miscellaneous injury
- Infection, burns etc.
Describe the assessment of a mangled extremity in terms of predicting need for amputation versus preservation.
The Mangled Extremity Severity Score (M.E.S.S.) stratifies risk according to the degree of Ischaemia, Soft tissue/skeletal injury type, Shock, and Age (I.S.S.A.): A score of greater than 7 predicts amputation (in retrospective series).
The N.I.S.S.S.A. scoring system includes nerve injury and the degree of soft tissue contamination is therefore more sensitive and specific; a score greater than 11 predicts amputation.
How is Traumatic Brain Injury Classified?
- Mild TBI
- Brief LOC for a few seconds/minutes, post-traumatic amnesia for less than an hour, normal CT, and GCS 13-15
- Moderate TBI
- LOC for less than 24 hours, PTA for 1-24 hours, abnormal CT, GCS of 9-12
- Severe TBI
- LOC or coma for >24 hours, PTA for more than 24 hours, abnormal CT, GCS 3-8
Describe the pathophysiology of trauma coagulopathy
Trauma-induced coagulopathy is generated by the following pathophysiological mechanisms:
-
Coagulation activation
- Procoagulants in the systemic circulation
- Impairment of endogenous anticoagulant activity
- Thrombin generation in the systemic circulation
-
Hyper-fibrino(geno)lysis
- Acute release of t-PA-induced hyperfibrino(geno)lysis
- Coagulation activation-induced fibrino(geno)lysis
- Consumption coagulopathy
What is a blast injury?
The physiological and anatomical insult to the human body caused by the physical properties of an explosion. Blast wave = shockwave that results from the explosion. Blast front = its leading edge. Blast wind = the rush of air caused by the blast wave.
In open air: force of blast rapidly dissipates
Within confined spaces: blast wave is magnified by its reflection off walls, floor and ceilings, increasing its destructive potential
Underwater: bc water is less compressible than air, an underwater blast wave propagates at high speeds & loses energy less quickly over long distances, being ~3x greater in strength than that which is detonated in air