Question | Answer |
defined as any condition in which there is inadequate delivery of oxygen and nutrients to the tissues to meet metabolic demands | Shock |
General signs/symptoms of shock | mental status changes, acidosis, oliguria, and poor cutaneous perfusion (cool, pale skin). |
a function of the cardiac output and the oxygen carrying capacity of the blood | Oxygen delivery |
divisions of shock | failures of the heart, failures of the blood, failure the vessels |
hemodynamic responses to compressive cardiac shock | decreased cardiac output, increased heart rate, large increase in LV filling pressures |
hemodynamic responses to cardiogenic shock | large decrease in cardiac output, increase in filling pressures |
hemodynamic responses to hypovolemic shock | decreased cardiac output, increased heart rate, large decrease in LV filling pressure, increased systemic resistance |
hemodynamic responses to septic shock | increased cardiac output, increased heart rate, large decrease in systemic resistance |
shock due to pump failure can be due to | extrinsic compression of the heart, or intrinsic heart failure |
results when compression of the great veins or heart itself retards blood return to the heart | cardiac compressive shock |
examples of cardiac compressive shock | pericardial tamponade, tension pneumo, diaphragmatic rupture, positive pressure ventilation |
With cardiac compressive shock,in addition to general signs of shock, physical exam reveals | hypotension, distended neck veins, pulmonary rales, Kussmaul's sign, and pulsus paradoxus |
rise in JVP with inspiration | Kussmaul's sign |
exaggerated decrease in systolic pressure with inspiration | pulsus paradoxus |
definitive treatment for cardiac compressive shock | correction of the mechanical abnormality |
can result from failure of the heart muscle, arrhythmia, valvular or septal defects, or excessive afterload | cardiogenic shock |
Physical exam of a patient in cardiogenic shock may reveal | signs of compensetory volume overload-distended neck veins, pulmonary rales, extra heart sounds, peripheral edema |
in cardiogenic shock due to inadequate pumping, improve pump function with | inotropes(dopamine, dobutamine), intra-aortic balloon pump |
in cardiogenic shock due to excessive afterload, reduce afterload with | vasodilators (ACEI's and nitrates |
in cardiogenic shock due to arrhythmias, optimize heart rate and rhythm with | beta-blockers, anti-arrhythmics, pacemakers |
in cardiogenic shock optimize volume status by | being cautious with fluid administration, and use diuretics if in CHF |
one of the most common causes of shock encountered in the practice of surgery | hypovolemic shock |
Hypovolemic shock may be due to blood loss as well as from | third spacing, protracted vomiting, diarrhea, sweat |
the sequestration of fluid into injured soft tissues or bowel | third spacing |
hypovolemia leads to | decreased venous return to the heart and decreased cardiac output |
decreased venous return to the heart | preload |
mild hypovolemia | <20% blood volume loss-decreased pulse pressure, postural hypotension, cutaneous vasoconstriction, collapsed neck veins, concentrated urine, hemoconcentration |
moderate hypovolemia | 20-40% blood volume loss-thirst, tachycardia, moderate hypotension, oliguria |
severe hypovolemia | >40% blood volume loss-mental status changes, arryhthmias, ischemic EKG changes, profound hypotension |
systolic pressure - diastolic pressure = __ | pulse pressure |
treatment for hypovolemic shock | Large-bore IV. Resuscitation should always begin with crystalloid infusion—30 cc/kg (2 liters for most adults) as fast as possible then titrate against signs of clinical improvement. Blood products may be appropriate in situations of blood loss. |
loss of venous tone reults in | venous pooling with decreased blood return to the heart (preload) and decreased cardiac output |
loss of arterial tone results in | decreased systemic vascular resistance (SVR) and hypotension. |
neurogenic shock | is a failure of the autonomic nervous system due to spinal cord injury or regional anesthetics |
injury above the level of __ results in a loss of sympathetic tone and adrenergic stimulation | T4 |
physical signs of neurogenic shock may include | warm, flushed skin, and bradycardia |
in neurogenic shock the loss of venous tone is exacerbated by | the loss of muscle tone |
treatment of neurogenic shock | IV fluids are the initial therapeutic agent since loss of venous tone results in relative hypovolemia. Peripheral vasoconstrictors are often required |
Septic shock is a complex phenomenon most commonly due to overwhelming infection from __ but can be due to any type of infection | gram negative bacteria |
In early septic shock, the response is __ | hyperdynamic with tachycardia and increased cardiac output |
In late septic shock __ | the cardiovascular system decompensates and progresses to a hypodynamic state |
Early clinical manifestations of septic shock include __ | fever, chills, bounding pulses, and warm, flushed skin in the setting of hypotension |
signs of progression to late septic shock are __ | Hypothermia, coagulopathy, pulmonary failure (ARDS), and renal failure |
definitive treatment of septic shock | clearance of the offending infection (surgical debridement or resection, appropriate antibiotic therapy) |
Potential indications for the transfusion of blood products | • the restoration and maintenance of normal blood volume• the correction of severe anemia• the correction of bleeding and coagulation disorders |
effect of administration of one unit of PRBC's | Hct increase by 3% |
effect of administration of one unit of platelets increases platelets county by __ | 40,000 |
effect of administration of one unit of cryoprecipitate | increase in fibrinogen by 3% |
indication for administration of PRBC's | hypovolemia + anemia, symptomatic anemia |
indication for administration of platelets in the presence of bleeding | plts <50,000 plts <15,000 (asymptomatic) |
indication for administration of FFP | bleeding + coagulopathy, coumadin reversal |
indication for administration of Cryoprecipitate | fibrinogen <100 mg/dL |
platelets are given for the correction of | thrombocytopenia |
indication for administration of platelets for asymptomatic thrombocytopenia | plts <15,000 |
a pool of platelets from six donors | six_pack |
FFP is given for the correction of the __ | vitamin K dependant clotting factors |
FFP contains | serum clotting factors (except VIII, and V), antithrombin III, fibrinogen, and proteins C and S |
is a plasma component that is enriched for high-molecular-weight proteins | Cryoprecipitate |
is a plasma componenet that is enriched for fibrinogen, factor VIII, factor XIII, and von Willebrand's factor | Cryoprecipitate |
occur when the recipient possesses antibodies against the donor RBC’s major (A, B, and Rh) or minor (Kell, Kidd, Duffy, et al.) antigens. | Hemolytic reactions |
acute (major) hemolytic reactions occur at the rate of 1/__ units | 20,000 |
delayed(minor) hemolytic reactions occur at the rate of 1/__ units | 500 |
symptoms of hemolysis | apprehension, headache, fever, chills, flank or chest pain, hematuria, and (in severe cases) hypotension |
Febrile nonhemolytic reactions may occur against | donor WBC's |
Disease transmission due to transfusion | is a rare but real phenomenon |
rates of CMV transmission from blood products __% unless CMV-negative requested | 50 |
rate of HIV transmission from blood products | 1/400,000-1/600,000 |
rate of Hep C transmission from blood products | 1/3000-1/6000 |
rate of Hep B transmission from blood products | 1/50,000-1/200,000 |
__due to the chelating action of the preservative sodium citrate can contribute to coagulopathy and should be corrected | Hypocalcemia |
__ can be associated with multiple transfusions of PRBC’s. | Dilutional coagulopathy |
• Some hemolysis of cells occurs during storage and administration, delivering an additional __ load to the recipient | potassium |
A __ device can filter blood collected during clean procedures and return it to the patient | “cell-saver” |
• Autotransfusion is an option for elective operations where significant blood loss is expected. The patient should ideally donate more than __ week prior to operation | 1 |
most common congenital abnormality of platelets | von Willebrand's disease |
five causes of shock | cardiogenic, hypovolemic, septic, neurogenic, anaphylactic |
MI, cardiomyopathy, valvular disease, rhythm disturbances, Pulm HTN, cardiac tamponade, tension PNX, diaphragm rupture (heart is compresed), PPV | Cardiogenic shock |
hemorrhage, severe dehydration, vomiting, diarrhea | Hypovolemic shock |
infection due to GNRs causing SIR, MOF, arterial vasodilation | Septic shock |
Spinal cord injury above T4 results in loss of sympathetic tone/adrenergic stimulation, regional anesthetics | Neurogenic shock |
hypersensitivity reaction | Anaphylactic shock |
initial treatment for cardiogenic shock | optimized volume status without overloading lungs, decrease afterload (ACEI, Nitrates), Heart rate control (betablockers, anti-arrhythmics, pacemaker), Inotropy (dobutamine, dopamine, milrinone, IABP, VAD’s, revascularization) |
initial treatment for hypovolemic shock | fluid resuscitation |
initial treatment for neurogenic shock | vasoactive agents may be needed, use fluid cautiously (watch for non-cardiac pulmonary edema) |
initial treatment for septic shock | treat underlying cause, try to identify organism, start broad spectrum empiric therapy, then narrow down when you find out the specific organism |
indication for administration of platelets as prevention before surgery | plts <15,000 |
most common reason for ABO mismatch | clerical error |
minor antigens | Kell, Kidd, Duffy |
every unit of blood you give __ the patient | immunocompromises |
hypocalcemia can lead to | decreased cardiac contractility, increased bleeding |
hyperkalemia in a transfusion patient can be due to | hemolysis |
be cautious in transfusing patients who are __ | immunocompromised (HIV, on steroids, organ transplant) |
signs and symptoms of anemia | fatigue, tachycardia, hypotension, mental sluggishness/disorientation, and shortness of breath |
__ reverses warfarin | FFP or Vitamin K |
__ may need platelet transfusions no matter what the platelet count | bleeding patients whose platelets have been impaired by aspirin or NSAIDs |
bleeding after cardiopulmonary bypass may be due to inadequate neutralization of heparin. Giving __ in this setting may worsen the bleeding because __ provides antithrombin III | FFP |
microvascular bleeding often indicates a | platelet defect |
__ impairs platelet function and can prolong bleeding | hypothermia |
blood should never __ | be infused with medications or solutions other than saline |
__ may result in significant blood loss without obvious bleeding | extensive tissue injury |
the first BP change seen in hypovolemia. when present it means class II hemorrhagic shock | increase in diastolic pressure |
systolic hypotension is a sign of | class III hemorrhagic shock |
agitation is another sign of | shock |
profound hypotension and apathy are signs of | class IV hypovolemic shock |
a normal 70 kg man has about __L of blood volume | 5 |
Humoral host defenses | antibody, complement |
ACT AS THE FIRST LINE OF CELLULAR DEFENSE | macrophages |
cellular host defenses | macrophages, t-cells |
What do cytokines do in infection | recruit macrophages |
phases of wound healing-inflamation days __ | 1-10 |
epithelialization, PMNs & macrophages | inflamation phase of wound healing |
proliferation phase of wound healing days __ | 5-3 weeks |
neovascularization, collagen production, granulation tissue, fibroblasts | proliferation phase of wound healing |
remodeling phase of wound healing weeks __ | 3 weeks - 1 year |
type III collagen replaced by type I, collagen cross-linking | remodeling phase of wound healing |
order of arrival of cells to wound | PLTs, PMNs, macrophages, fibroblasts, lymphocytes |
organism from dog bites | streptococcus viridans |
organism from cat bites | pasteurella |
with animal bites consider | tetanus, rabies, augmentin, cephalexin |
uninfected operative wound in which no inflammation is encounteredthe respiratory, alimentary, genital or infected urinary tract is not entered | clean wound |
Respiratory, alimentary, genital or urinary tracts are entered under controlled conditionsno unusual complications | clean_contaminated wound |
open, fresh, accidental wounds; operations with major breaks in sterile technique or gross spillage from the gastrointestinal tracteg. Gunshot wound to colon | contaminated wound |
old traumatic wounds with retained devitalized tissuethose that involve existing clinical infection or perforated visceraeg. Abscess | dirty |
perioperative antibiotics are given | 1 hour prior to skin incision |
choice of antibiotics depends on | type of operation |
surgical prophylaxis with first generation cephalosporin (Ancef) if | no anearobes are expected |
surgical prophylaxis with second generation cephalosporin (Cefotetan) if | anearobic activity is likely |
in a rapidly spreading infection think about | necrotizing fasciitis |
necrotizing fasciitis can be caused by | clostridium perfringens, streptococcus (GABHS) |
aka. Strep gangrene, Fournier's gangrene, flesh eating disease | necrotizing fasciitis |
severe infection that leads to necrosis of the subcutaneous tissue and adjacent fascia | necrotizing fasciitis |
mortality rate in patients with necrotizing fasciitis __% | 40 |
treatment for __ includes broad-spectrum antibiotics, including Penicillin G,+ aggressive surgical debridement! | necrotizing fasciitis |
Must have high index of suspicion for __ whenSkin discoloration, necrosis, crepitus, drainage of thinWatery, grayish, foul-smelling fluid present. | necrotizing fasciitis |
antibiotics usually not helpful with | Post-op Wound infection>48 hours 5-10 days post-op |
local infection of the dermis and subcutaneous tissue characterized by spreading redness, swelling and pain | cellulitis |
blanching erythema | cellulitis |
#1 risk factor for development of pneumonia after surgery | bed rest |
most common post-operative infection | UTI |
four W's of fever | wind, water, wound, wonder drugs |
#1 cause of post op fever | atelectasis |
atalectasis occurs < post operative day __ | 3 |
uti occurs post operative day __ | 3 |
fever for wound infection occurs post operative day __ | 5 |
Abscess/pus collection in thorax | Empyema |
diarrhea in the hosptital is usually from infection due to overgrowth of | clostridium difficile |