Imaging in the Trauma Patient David A. Spain, MD Department of Surgery Stanford University Pan Scan Instead of Clinical Exam? 1
Granted, some patients don t need CT scan Platinum Package Stanford Special CT Scan Head Neck Chest Abdomen Pelvis With T/L spine reformats Takes about 30 minutes to do 2
LightSpeed The Power to Scan. Finer. Faster. Further. The New ABCs Admit Begin CT scan Examine pt only if CT doesn t tell you what s wrong the CT-directed physical exam 3
Everybody loves CT scan Often times, resuscitation seems like a race to CT scan Sometimes pt s taken to CT after barely completing primary survey, let alone the secondary portion Death begins in X-ray 4
True Case Young year old man Restrained passenger Side impact on his side Intubated in field (mental status)? Right chest crepitance Being wheeled to CT scan when trauma resident stopped and insisted on reviewing CXR 5
Dilemma What s the cost of a CT scan real $$ Versus Cost of missed or delayed injuries Faster thru put (double-edge) Peace of mind Can you accurately predict who needs or doesn t need a CT scan? Injuries distracting from IAI after blunt trauma Prospective study, GCS 15 and CT of abdomen or DPL Presence of pain and/or tenderness sensitivity 82% specificity 45% positive predictive value 21% negative predictive value 93% Abdominal pain and/or tenderness higher incidence of IAI, the lack of these findings did not preclude IAI Am J Emerg Med 1998;16:145-9 6
CT for blunt abdominal trauma in the ED: a prospective study. 196 patients were evaluated Abdominal tenderness present in 120 22 patients had IAI (11%) Abnormal abdomen PE and hematuria sensitivity of 64% specificity of 94% positive predictive value of 56% negative predictive value of 95% Am J Emerg Med 1998;16:338-42 Absence of IAI predicted with sensitivity 100% & specificity 87% 7
Use of abdominal CT in blunt trauma: do we scan too much? Only 37% (40 of 109) of scans were suggestive of IAI Accuracy in predicting positive scans in equivocal cases is poor Two clinical prediction rules were found in the literature Accurate retrospectively, but haven t been used prospectively 8
Admit or obs is not necessary after a negative Abd CT: results of a prospective, multi-institutional trial 22 months at four Level I trauma centers All patients with blunt abdominal trauma suspected by either PE or mechanism were evaluated by protocol PE in the ED Abdominal CT scan Hospitalization for observation Standardized PE repeated 4-8 hrs later J Trauma 1998;44:273-80 Admit or obs is not necessary after a negative Abd CT 2299 fulfilled the entire study protocol 21% were positive 19% patients with a positive CT scan had no tenderness Negative predictive power of abd CT scan based on prelim reading and need for a laparotomy was 99.63% 9
Can we omit head CT?? Loss of consciousness: when to perform computed tomography? Kids w/ LOC or amnesia and GCS 13-15 should have a head CT to avoid missing an intracranial injury Minor head trauma: Is computed tomography always necessary? Routine head CT in pts with LOC/amnesia but no Sx/signs of depressed skull fracture has minimal value and not warranted NEXUS Value of repeat cranial CT in patients with minimal head injury MHI and a positive cranial CAT scan 151 had a persistently normal or improved neurological examination none required after the repeat cranial CAT scan? Value repeat CAT scan in this setting J Trauma 2004;56:475-80 10
Do we really need CT in primary evaluation of blunt chest trauma in patients with "normal" CXR? 93 consecutive patients 76% MVC > 10 mph 24% after fall > 5 ft 25 had normal CXR and 13 (52%) CT scan showed multiple injuries 2 (8%)aortic lacerations 3 pleural effusions 1 pericardial effusion J Trauma 2001;51:1173-6 Reevaluation of diagnostic procedures for transmediastinal gunshot wounds 22 stable patients CT scans were positive in 7 Directed further diagnostic evaluation 2 operations 68% had negative CT scans and were observed without further evaluation No missed injuries Hospital charges generated with CT-based protocol were significantly less J Trauma 2002;53:635-8 11
Reformatted visceral protocol HCT vs. conventional radiographs of T and L spine in blunt trauma patients prospective evaluation of consecutive patients with thoracic and lumbar spine fractures Screening sensitivity Reformatted HCT: 97% (T) and 95% (L) Conventional Xray:62% (T) and 86% (L) J Trauma 2003;55:665-9 It s always good to exam the patients Restrained rear seat passenger with seatbelt, c/o some abd pain 12
Reliability of clinical exam in detecting pelvic fx in blunt trauma 12 studies with 5454 patients 49 false neg cases fx majority had either altered consciousness or minor pelvic fracture only Only 3 clinically relevant pelvic fractures were missed among 441 pts with fracture within a total population > 5000 In stable and alert trauma pts, thorough exam will detect pelvic fractures with nearly 100% sensitivity 13
Selective management of penetrating neck trauma based on level of injury 312 pts over 18 years 75% stab, 25% GSW Zone I=13%, Zone II=67%, Zone III=20% 34% early exploration (16% nontherapeutic) 66% observed (0.5% delayed exploration) Am J Surg 1997;174:678-82 82 Selective Management Unstable Hard signs OR Penetrating Neck Injury Symptoms or Signs Zone I Zone II Zone III study OR angio Asymptomatic Zone I study Zone II/III observe 14
You can t get it back in 15
Pan Scan CT of the head, cervical spine, chest, abdomen, and pelvis, with the following inclusion criteria: (1) no visible evidence of chest or abdominal injury (2) hemodynamically stable (3) normal abdominal examination results in a neurologically intact patient or unevaluable abdominal examination results secondary to a depressed LOC, and (4) significant mechanisms of injury Main Outcome Measure Any alteration in the normal treatment plan as a direct result of CT scan findings. Included: Early hospital discharge Admission for observation Operative intervention Additional diagnostic studies or interventions 16
Results: 1000 patients underwent pan scan during the 18-months 592 were evaluable patients with no obvious signs of abdominal injury Clinically significant abnormalities were found in 3.5% of head CTs 5.1% of cervical spine CTs 19.6% of chest CTs 7.1% of abdominal CTs Overall treatment was changed in 19% of patients based on abnormal CT scan findings 17
Pan Scan We believe that a liberal policy of CT scanning is warranted in patients with blunt multisystem trauma, even among select patients without obvious signs of injury. Although the overall incidence of significant injuries identified by the pan scan was low among evaluable patients, it did prompt immediate intervention in several potentially life-threatening injuries. Of equal or greater importance is the value of a normal pan scan in reliably excluding significant injuries and allowing for earlier discharge or disposition of patients. Not an either/or question CT scan technology will continue to improve Faster More accurate Supplanting other invasive modalities CT is complimentary to good initial assessment and serial examinations 18
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