Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Surgery Review 4
SR 4: Trauma, Critical Care, Burns, Plastics, Skin, Soft Tissue
| Question | Answer |
|---|---|
| What is the LD50 and LD90 of falls? | LD50 = 48 feet (4 stories), LD90 = 84 feet |
| What is a positive DPL? | Gross blood (>10cc), or identification of bile, bacteria, food particles, or >500 WBCs or >100,000 RBCs |
| What does a DPL miss? | retroperitoneal bleeds and contained hematomas |
| What does FAST scan miss? | retroperitoneal bleeding and hollow viscus injuries |
| What are the signs of abdominal compartment syndrome? | Bladder pressures >25-30, increased ventilatory peak pressures (upward displacement of diaphragm), hypotension, decreased urinary output (renal vein compression) |
| What are the operative indications for intracranial hemorrhage? | Significant neurologic degeneration or mass effect (>5mm) |
| How do you calculate cerebral perfusion pressure? | CPP = MAP – ICP, keep >60 |
| What is the cause of an epidural hematoma? | arterial bleeding from middle meningeal artery |
| What is the cause of a subdural hematoma? | Most commonly from tearing of venous plexus (bridging veins) between dura and arachnoid |
| What are the possible supportive treatments for elevated ICP? | Treat if >20: sedation (barbituate coma) and paralysis, elevate head of bed, relative hyperventilation (CO2 30-35), keep Na 140-150 and serum osm 295-310, mannitol, ventriculostomy with CSF drainage, decrompressive craniotomy |
| When does peak intracranial pressure occur after traumatic brain injury? | 48-72 hours |
| What does a dilated pupil after TBI suggest? | Uncal herniation on same side (CN III compression) |
| What cranial nerves are commonly injured with temporal skull fractures? | CN VII and VIII |
| What is the most common site of facial nerve injury? | Geniculate ganglion |
| What are the operative indications for a skull fracture? | Significantly depressed (8-10mm), contaminated, or persistent CSF leak |
| What are the signs of basal skull fractures? | Anterior fossa fracture – raccoon eyes; middle fossa fracture – battle’s sign |
| What is a Jefferson fracture? | C1 burst fracture caused by axial loading (diving into shallow water) |
| What is a hangman’s fracture? | C2 fracture caused by distraction and extension |
| What are the types of odontoid fractures? | I – above base, stable; II – at base; III – extends into vertebral body. II+III are unstable and need fusion or halo |
| Describe the columns of the thoracolumbar spine | Anterior – anterior longitudinal ligament and ½ of vertebral body; Middle – posterior ½ of vertebral body and posterior longitudinal ligament; Posterior – facet joints, lamina, spinous processes, and interspinous ligaments |
| When is a thoracolumbar spinal fracture considered unstable? | If more than one column is disrupted |
| What fractures are at risk from an upright fall? | Calcaneus, lumbar, and wrist/forearm |
| What is the number 1 indicator of mandibular injury? | Malocclusion |
| Describe the zones of the neck | I – clavicle to cricoid cartilage; II – cricoid to angle of the mandible; III – angle of the mandible to base of skull |
| What is the best modality to diagnose traumatic esophageal injuries? | Rigid esophagoscopy and esophagogram – finds 95% of injuries when combined |
| What is the operative approach to esophageal injuries? | Neck – left side, upper 2/3 of esophagus – right thoracotomy, lower 1/3 – left thoracotomy |
| What are the indications for thoracotomy after chest tube placement? | >1500 cc blood initially, >200 cc/hr x3 hrs, or >2500 cc x 24hrs |
| What is the operative approach to traumatic tracheobronchial injury? | Operate if large air leak and respiratory compromise or after 2 weeks of persistent air leak. Left thoracotomy only for distal left mainstem injuries, all others get right thoracotomy to avoid aorta |
| What do you suspect if an air-fluid level is seen in the left chest after blunt injury? | Diaphragm rupture with stomach herniation into chest |
| What is the treatment for traumatic diaphragmatic injury? | Approach via abdomen if <1 week, via chest if >1 week since injury |
| Where are traumatic diaphragm injuries usually located? | 8:1 on the left |
| What are the signs of aortic transection? | widened mediastinum, 1st rib fracture, apical capping, loss of aortopulmonary window, loss of aortic contour, left hemothorax, tracheal deviation |
| Where is the most common location of aortic transection? | At ligamentum arteriosum just distal to subclavian takeoff |
| What is the treatment of penetrating “box” injuries? | Borders are clavicles, xiphoid process, and nipples – need pericardial window, bronchoscopy, esophagoscopy, and barium swallow |
| What is the treatment of a penetrating chest wound outside the “box” without pneuomothorax or hemothorax? | Still needs chest tube if patient required intubation, otherwise follow CXRs |
| What type of bleeding is associated with pelvic fractures? | Anterior pelvic fractures are more likely to have venous bleeding whereas posterior fractures have arterial |
| What is the most common area of duodenal trauma? | Second portion near ampulla of vater |
| What is the surgical treatment for duodenal trauma? | 80% can be treated with debridement and primary closure, but may need pyloric exclusion and gastrojejunostomy to allow healing |
| What is the cause of a high SBO 12-72 hours after blunt traumatic injury? What is the treatment? | Missed duodenal hematoma – treat with TPN and NGT – 90% cured over 2-3 weeks |
| What is the treatment for traumatic common bile duct injury? | <50% circumference – repair over stent; >50% - choledochojejunostomy |
| When has conservative management of a blunt liver injury failed? | Patient is unstable despite aggressive resuscitation, or requires >4 units RBC to keep Hct over 25 – Go to OR |
| When has conservative management of a blunt splenic injury failed? | Patient is unstable despite aggressive resuscitation, or requires >2 units RBC to keep Hct over 25 – Go to OR |
| Which is performed first: vascular repair or orthopedic repair? | Vascular repair |
| What is the best way to repair a posterior IVC repair? | Through the anterior wall |
| What is the best indicator of renal trauma? | Hematuria |
| What is the treatment of a left renal vein injury? | Can ligate near IVC because of adrenal and gonadal vein collaterals, cannot do this on right |
| What is the treatment for a traumatic bladder injury? | Extraperitonal - a/w pelvic fx, foley only for drainage; Intraperitoneal - no pelvic fx, more likely in kids, usually dome rupture - laparotomy with multi-layer closure and foley |
| How is a traumatic urethral injury diagnosed? | retrograde urethrogram (RUG), do not place foley - needs suprapubic catheter |
| What is a test can you do to assess fetal maturity in a pregnant trauma patient? | lecithin:sphingomyelin (LS) ratio > 2:1; positive phosphatidylcholine |
| What is the Kleihauer-Betke test? | Test for fetal blood in maternal circulation – sign of placental abruption |
| What are the indications for C-section during trauma ex-lap? | persistent maternal shock, near term (>34 wks) and mother with severe injuries, pregnancy a threat to mother’s life (DIC, hemorrhage), mechanical limitation to life-threatening vessel injury, direct uterine trauma |
| What determines stroke volume? | LVEDV, contractility, and afterload |
| What is the Anrep effect? | automatic increase in contractility secondary to increased afterload |
| What is the Bowditch effect? | automatic increase in contractility secondary to increased HR |
| What equation describes O2 delivery? | CO x CaO2 = CO x (Hgb x 1.3 x SpO2) |
| What causes a right shift of the oxygen disassociation curve? | Oxygen unloading – increased CO2, temperature, ATP, 2,3DPG, or decreased pH |
| What does an elevated mixed venous oxygen saturation (SvO2) indicate? | >77% - shunting or decreased O2 extraction – sepsis, cyanide poisoning, cirrhosis, hypothermia, paralysis, coma |
| What does a decreased mixed venous oxygen saturation (SvO2) indicate? | <66% - decreased cardiac output or decreased oxygen saturation |
| What are relative contraindications to placing a Swan-Ganz catheter? | previous pneumonectomy or left bundle branch block |
| What do you do if you encounter hemoptysis after Swan placement? | Pull catheter back slightly and inflate balloon and increase PEEP (will tamponade the pulmonary artery bleed), mainstem intubate nonaffected side; may need thoracotomy and lobectomy |
| What are the approximate Swan distances to wedge from the various central access locations? | R SCV – 45cm, R IJ – 50cm, L SCV – 55cm, L IJ – 60cm |
| Where does blood have the lowest venous saturation? | Coronary venous blood (30%) |
| What is the initial alternation in hemorrhagic shock? | Increased diastolic blood pressure |
| What is the cause of petechiae, hypoxia, and confusion/agitation after a femur fracture? How is the diagnosis made? | Fat emboli; sudan red stain may show fat in sputum and urine |
| What is the treatment for air emboli? | Place patient head down and roll to left (keeps air in RV and RA), then aspirate out air with central line or PA catheter to RA/RV |
| What are the effects of an intraaortic balloon pump (IABP)? | Augments diastolic coronary blood flow and reduces afterload by inflating during diastole (inflates 40msec before T wave, deflates with p wave) |
| What do dopamine receptor agonists do? | Relax renal and splanchnic smooth muscle |
| What are the effects of alpha-1, alpha-2, beta-1, and beta-2 adrenergics? | alpha-1 – vascular smooth muscle/gluconeogenesis, alpha-2 – venous smooth muscle, beta-1 – myocardial contraction and rate, beta-2 – relaxes bronchial smooth muscle and vascular smooth muscle |
| What is the mechanism and effect of milrinone/amrinone? | phosphodiesterase inhibitor (increases cAMP) resulting in increases Ca flux and myocardial contractility - inotrope, increases CO and decreases SVR |
| What is a potential side-effect of excessive nipride infusion? What is the treatment? | cyanide toxicity, can check thiocyanate levels – treat with amyl nitrite then sodium nitrite |
| What is the difference between nipride and nitroglycerine effects? | Both work via nitric oxide (vasodilation) but nipride is an arterial and venous dilator whereas nitroglycerine is predominantly venodilatation; both can lead to pulmonary shunting |
| What is the effect of increased PEEP? | improves oxygenation by alveoli recruitment and increases FRC |
| What are the effects of aging on the pulmonary system? | Increased FRC, decreased compliance and FEV1 |
| What is functional residual capacity (FRC)? | air in lungs after normal exhalation [expiratory reserve volume (ERV) + residual volume (RV)] |
| What is inspiratory capacity? | maximum amount of air able to be inhaled (TV + IRV) |
| What is vital capacity? | greatest volume of air that can be exhaled (TV + IRV + ERV), also called forced vital capacity (FVC) |
| How does restrictive lung disease differ from obstructive lung disease on pulmonary function studies? | Restrictive – decreases TLC, RV, and FVC; Obstructive – increases TLC, RV, but decreases FEV1 |
| What are the physiological effects of ARDS? | decreased pulmonary compliance and increased protinaceous material, causing increased gradient and increased shunt |
| What is Mendelson’s syndrome? | chemical pneumonitis from aspiration of gastric secretions |
| What is the most frequent site of aspiration? | posterior portion of RUL and superior portion of RLL |
| What are 3 laboratory indicators of low volume, “pre-renal” azotemia? | FeNa < 1, urine Na < 20, or BUN/Cr ratio >30 |
| What triggers renin release? | Low Na sensed by macula densa of JG apparatus or decreased BP sensed by baroreceptors |
| Where is angiotensin I converted into angiotensin II? | In the lung by angiotensin converting enzyme (ACE) |
| What are the effects of angiotensin II? | vasoconstrictor, increases HR/contractility, inhibits renin release, releases aldosterone |
| What is the treatment of carbon monoxide poisoning? | 100% O2 – decreases CO half life from 5 hrs to 1 hr |
| What are admission criteria for burns? | 2nd + 3rd degree >10% TBSA patients <10 or >50, or >20% TBSA in other patients; >5% 3rd degree burns, suspected abuse |
| What is the parkland formula? | For burns >20% - 4cc x kg x %TBSA. LR fluid is given over 24 hours but 1/2 is given in first 8 hours |
| What is the cause of inhalational injury? | carbonaceous materials and smoke, not heat |
| What are risk factors for airway injury? | EtOH, trauma, closed space, rapid combustion, extremes of age, delayed extrication |
| What is the most common infection in burn wound patients? | Pneumonia |
| Which chemicals produce deeper burn wounds: acids or alkalis? | Alkalis due to liquefaction necrosis |
| What is the hallmark of acid burn wounds? | coagulation necrosis |
| What is the treatment for hydrofluoric acid burns? | spread calcium on wound |
| What is the treatment for tar burns? | Cool, then wipe away with lipophilic solvent |
| What is the treatment for electrical burns? | Cardiac monitoring, monitor for rhabdomyolysis and compartment syndrome |
| What is a contraindicated to skin grafting a burn wound? | Cultures positive for beta-hemolytic strep or bacteria >10^5 |
| How long do homografts and xenografts generally last? | homografts 2-4 weeks, xenografts 2 weeks |
| What are the goals for surgery in burn wound excision and grafting? | <1L blood loss, <20% skin excised, and <2 hours in OR |
| What is the most common reason for skin graft loss? | hematoma or seroma formation under graft |
| What is the treatment for extensive deep burns to the palm? | Splint hand in extension for 1 week, then graft in week 2 with FTSG |
| What is the most common organism in burn wound infections? | Pseudomonas, common in burns >30% TBSA |
| What are the characteristics of silvadene? | Poor eschar penetration, risk of neutropenia and thrombocytopenia, good candida/pseudomas coverage, do not use if sulfa allergy |
| What are the characteristics of sulfamylon? | Painful, can cause metabolic acidosis (carbonic anhydrase inhibitor), good eschar penetration |
| What are the characteristics of silver nitrate? | Can cause hyponatremia and hypochloremia due to leeching of NaCl |
| What is the most common viral infection in burn wounds? | HSV |
| What is the best way to detect burn wound infection (and differentiate from colonization)? | biopsy of wound |
| What is symblepharon? | Eyelid stuck to conjunctiva after burn, treat with release with glass rod |
| What is a Marjolin’s ulcer? | SCCA that develops in a chronic burn wound |
| What is the pathophysiology and treatment of toxic epidermal necrolysis? | Epidermal-dermal separation; supportive care, topical abx, xenografts – NO steroids |
| What is the pathophysiology and treatment of Stevens-Johnson syndrome? | hypersensitivity reaction – more severe TEN with subepidermal bullae, epidermal cell necrosis, and dermal edema; Tx – supportive care, topical abd, xenografts – NO steroids |
| What is the function of Pacinian corpuscles? | sense pressure |
| What is the function of Ruffini’s endings? | sense warmth |
| What is the function of Krause’s end-bulbs? | sense cold |
| What is the function of Meissner’s corpuscles? | tactile sense |
| Which skin grafts are more likely to survive, split thickness or full thickness? | split-thickness because graft is not as thick so easier for imbibation and subsequent revascularization to occur |
| What are the three steps to the healing of a skin graft? | Imbibition, inosculation, revascularization |
| What is the most common cause of pedicled or anastomosed free flap tissue necrosis? | venous thrombosis |
| What is the most important determinator of TRAM flap viability? | periumbilical perforators |
| What are risk factors for melanoma? | dysplastic, atypical or large congential nevi (10% risk), familiar BK mole syndrome (essentially 100% risk), xeroderma pigmentosum, fair complexion, sun exposure, previous skin cancer/XRT |
| What are the common sites of melanoma? | Skin > eyes > rectum; #1 skin site for men = back, women = legs; Worse prognosis on "BANS" – back, arms, neck, scalp |
| What is the most common location of metastases from melanoma? | lungs |
| What is the most common primary with a metastases to the small bowel? | melanoma |
| What are the four major types of melanoma? | superficial spreading (most common), acral lentiginous, lentigo maligna, and nodular |
| What types of melanoma have the best and worst prognosis? | Best – lentigo maligna; Worst – nodular |
| What are the surgical margins for resection of a melanoma? | in situ = 0.5cm margin; <1mm depth = 1 cm margin; 1-2mm depth = 1-2 cm margin (with SNL); >2mm depth = 2 cm margin |
| What is the Breslow classification of melanoma and associated survivals? | <1mm thickness (95% 5 yr survival); 1-2mm (80-95%); 2-4mm (60-75%); >4mm (50%) |
| What is the most common malignancy in the United States? | Basal cell carcinoma |
| What type of skin cancer has a pearly appearance and rolled borders? | basal cell carcinoma |
| What type of cancer demonstrates “peripheral palisading” of nuclei and “stromal retraction artifact”? | basal cell carcinoma |
| What is the most aggressive subtype of BCC and what is it characterized by? | morpheaform – has collagenase production |
| What type of skin cancer has overlying erythema and is papulonodular with crust and ulceration? | Squamous cell carcinoma |
| What is the three most common soft tissue sarcomas? | 1 – malignant fibrous histiosarcoma, 2 – liposarcoma (thigh, retroperitoneum), 3 - leiomyosarcoma |
| What are the recommendations for biopsy of an extremity sarcoma? | Excisional if < 4cm, otherwise longitudinal incision (less lymphatic disruption, easier to excise scar if biopsy positive) |
| What is the criteria for high-grade histologic grading of a sarcoma? | more than 5 mitoses per HPF, prominent vascularity, hyperchromatic nuclei, and necrosis |
| What are the indications for radiation to a sarcoma? | close margins (want at least 3 cm and one uninvolved fascial plane), >5 cm, or high grade |
| What is the difference between actinic, seborrheic, and arsenical keratoses? | actinic and arsenical are premalignant (SCCA risk, from sun or arsenic, respectively), seborrheic has no cancer risk |
| What is Bowen’s disease? | SCCA-in-situ, 10% turn invasive |
| How does brown fat differ from white fat? | less metabolically active, but more mitochondria and more capillaries – abundant in newborns and hibernating animals |
| Where is brown fat located in an adult? | Mostly located in neck, axilla, and interscapular regions |
| What is the treatment of Kaposi sarcoma | XRT – surgery indicated for biopsy purposes only |
| What is the pathophysiology of hidradenitis? | inflammatory infiltrate of apocrine glands, thus seen after puberty |
Created by:
jclanton82
Popular Surgery sets