Transcript Principles of Surgery (POS) Trauma & Critical Care Review

Principles of Surgery (POS)
Critical Care Review
D.Kubelik
University of Ottawa
POS Lecture Series 2012
Adapted from D.Kim
Objectives

review ATLS principles

discuss basic physiologic concepts as
applicable to critical care/ICU

apply these principles to case based
scenarios
Critical Care
Cardiac Physiology
PAWP ~ Left atrial pressure
 CVP ~ Right atrial pressure

Exams

Approaches to questions that give central pressure
data
 Is the heart working well?



If CO is low where is the problem



Use the cardiac index/cardiac output
If the CO is high look for distributive causes of shock
Look at where pressures are increasing
This is usually proximal to the disease
E.g. PE  high RV and CVP but normal wedge
Shock

Approach to a hypotensive patient

MAP = CO x SVR
Decreased Cardiac Output
Decreased SVR






Sepsis
Neurogenic Shock
Adrenal Insufficiency
Liver Failure
Anaphylaxis
Medications
Classifying Shock
Hypovolemic
 Cardiogenic
 Obstructive
 Distributive
 (Endocrine)


Can have cardiogenic or
distributive components

A 51 YO patient with known lung cancer undergoing
radiation therapy presents to the hospital with
worsening shortness of breath. He becomes
hypotensive and gets admitted to the ICU. He has a CI
of 1.9, CVP 20, PAWP 20, RV pressures 35/20 PA
pressures 32/20. What is the most likely diagnosis
PE
 MI
 Pneumonia and sepsis
 Cardiac Tamponade

Tamponade
Intrapericardial pressure equalizes
and opposes atrial and ventricular
pressures
 Hypotension, tachycardia, high CVP
and pulsus paradoxus (drop
>10mmHg in pressure with
inspiration)


A 51 YO patient with known lung cancer undergoing
radiation therapy presents to the hospital with
worsening shortness of breath. He becomes
hypotensive and gets admitted to the ICU. He has a CI
of 1.9, CVP 18, PAWP 10, RV pressures 50/33 PA
pressures 50/20. What is the most likely diagnosis
PE
 MI
 Pneumonia and sepsis
 Cardiac Tamponade

Treatments
1. Which of the following is/are not a
determinant of CO?
a) end-diastolic pressure
b) afterload
c) contractility
d) heart rate
e) ventricular interaction
Key Equations
CO = HR x SV
SV = EDV – ESV
EF = SV / EDV
MAP = CO x SVR
Frank-Starling
2. Which of the following mechanisms are the body’s
most important defenses in severe oxygen transport
deficiency?
a) hyperventilation
b) reduction of VO2
c) organ redistribution of CO
d) shifting of the O2 dissociation curve
e) widening of the a-v O2 content

The oxyhemoglobin dissociation curve relates the
partial pressure of O2 in the blood (PO2) to the %
saturation of hemoglobin with oxygen (SO2). For a
given SO2, the PO2 depends on all of the following,
EXCEPT?
1)
2)
3)
4)
temperature
serum potassium
pH
RBC content of 2,3-DPG
Hemoglobin-O2 Dissocation Curve
Remembering the dissociation
curve

A shift to the right means
oxygen is unloaded
“Exercising muscle needs
oxygen”
Increased temp, CO2,
acidosis, glycolysis
 2,3 DPG is a glycolysis
breakdown product
Compare curves for a set pO2


3. What is the definition of the shock
state?
a) low BP to maintain normal metabolic and
nutritional metabolism
b) low CO to maintain normal metabolic and
nutritional metabolism
c) inadequate tissue perfusion to maintain
normal metabolic and nutritional metabolism
d) abnormal vascular resistance to maintain
normal metabolic and nutritional metabolism
DO2-VO2 Equations
4. In which of the following is CVP a
reliable guide in fluid management?
a) CXR with pulmonary edema
b) RVEDP = CVP
c) MV disease
d) LVEF = 0.4
e) PHTN
CVP and PCWP
5. Which of the following are determinant of
mixed venous O2 saturation (SvO2)?
a) VO2
b) CO
c) Hb Concentration
d) arterial O2 saturation
e) myocardial VO2
6. Which of the following is/are
associated with en elevated SvO2?
a) septic shock
b) distal migration of the PAC
c) lactic acidosis
d) left-to-right shunt
e) right-to-left shunt
7. Regarding CO2 kinetics, which of
the following is/are true?
a) total amount of CO2 produced is equivalent to
the total amount of O2 consumed
b) the a-v difference of CO2 is the same as O2
c) end-tidal CO2 is the same as paCO2
d) all of the above
CO2 metabolism
8. Which of the following is/are associated
with increased dead space ventilation?
a) low CO
b) ARDS
c) PE
d) PHTN
e) all of the above
9. With regards to ventilatory mechanics, which
of the following statements is/are true?
a) WOB consume 2% of total body O2 consumption
b) WOB may increase to 50% in the postop patient
c) the increased WOB in COPD is due primarily to an
increased inspiratory effort
d) airway pressure reflects the compliance of the chest
wall and diaphragm as well as the lungs
e) C = V / P
Compliance & Resistance
10. Which of the following indicates the
need for immediate ventilatory support?
a) RR > 35bpm
b) paCO2 >60mmHg
c) A-a O2 gradient > 350mmHg
d) VD/VT >0.6
e) shunt fraction greater than 5%
11. ARDS is characterized by:
a) bilateral pulmonary infiltrates
b) paO2/FiO2 <300mmHg
c) PCWP >18mmHg
d) hypoxemia with hypercarbia
e) increased dead space ventilation and
increased lung compliance
12. Which of the following treatment are
appropriate for the ARDS patient?
a) MV
b) albumin and Lasix
c) PEEP
d) ECMO
e) routine steroids
13. With regards to FRC, which of the
following is/are true?
a) FRC = RV + TV
b) atelectasis occurs when the FRC falls
below the closing volume (CV)
c) FRC = ERV + RV
d) FRC is increased by PEEP
PFTs
14. Which of the following may be
seen with shock?
a) hyperglycemia
b) negative nitrogen balance
c) lactic acidosis
d) metabolic alkalosis
e) hyperkalemia
15. 24yo female undergoes ex lap for a Class IV
hemorrhage and is transfused >12U PRBCs. Which of the
following is most appropriate?
a) CaCl
b) FFP
c) plt
d) correction of hypothermia
e) heparin
Trauma
Primary Survey
22yo male post-MVC, combative, pale,
bleeding profusely from nose and mouth
 R thigh deformity and scalp laceration
 BP=80/40; HR=130; RR=40

Which of the initial management options
is correct?
a) esophageal intubation, rapid infusion RL 2L via CVC,
traction, suture scalp
b) ETT, rapid infusion RL 2L via 2 peripheral IVs,
traction, suture scalp, exposure
c) O2 by mask, rapid infusion RL 2L via 2 peripheral IVs,
traction, pressure scalp, exposure
d) cricothyroidotomy, rapid infusion RL 2L via 2
peripheral IVs, traction, pressure scalp, exposure
e) jaw thrust, rapid infusion RL 2L via 2 peripheral IVs,
traction, suture scalp, exposure
32yo female jumper from 10th floor
 head and extremity injuries
 apneic in ED

By which method is a definitive airway
provided for this patient?
a) orotracheal intubation
b) nasotracheal intubation
c) cricothyroidotomy
d) needle cricothyroidotomy
\
22 yo male automobile fire
 carbonaceous sputum, stridor
 failed nasotracheal intubation
 O2=97%

Prior to orotracheal intubation, what
step(s) is/are correct?
a) preoxygenation via high-flow O2
b) cricoid pressure
c) prepare for crico
d) axial stabilization
e) all of the above
56yo male ped struck
 multiple facial lacs, profuse bleeding
from nose and deformed mandible
 periorbital swelling and inability for
upward gaze
 RR=40, stridor, anxious

What is the appropriate next sequence?
a) O2, CT, suture, lateral c-spine
b) nasotracheal intubation, posterior packing, lateral cspine, CT face
c) endotracheal intubation, posterior packing, lateral cspine, CT scan of face
d) endotracheal intubation, posterior packing, lateral cspine, x-ray face
e) posterior packing, endotracheal intubation, lateral cspine, CT scan of face
22 yo male stab along ant. border of
SCM 1 cm sup. to cricoid
 platysma penetrated
 VSS

Which of the following management
option(s) is are correct?
a) admit to ICU and observe for airway obstruction and
expanding hematoma
b) perform carotid angio(graphy), if normal, observe
c) perform carotid angio, barium swallow, rigid
esophagoscopy, if normal, observe
d) explore neck
e) perfrom carotid angio, barium swallow, flexible
esophagoscopy, if normal, observe
24 yo male unrestrained driver MVC
 hypoxic despite O2
 CXR - bilateral chest infiltrates

Which of the following in the most likely
diagnosis?
a) bilateral pneumonia
b) ARDS
c) aspiration pneumonia
d) atelectasis
e) pulmonary contusion
Which of the following modalities in the
most important for identifying patients at
risk for complications from myocardial
contusion?
a) serial CK and TnI
b) ECG
c) echo
d) spiral CT
e) cardiac angio
40 yo male stab to left 7th intercostal in
the anterior axillary line
 clinically stable, clear BS bilat
 CXR - no ptx, no hemo

Which of the following statement(s)
is/are true?
a) absence of hemo/pneumo indicates that the
pleural cavity was not entered
b) absence of hemo/pneumo rules out
intraabdominal injury
c) if the pat. is to have GA, he must first undergo
a left sided chest tube insertion
d) further evaluation should be carried out to rule
out intraabdo. injury
30 yo male stab wound to right midinfraclavicular region
 weak pulse in bus 10 minutes ago
 now, no pulse or BP in ED with reactive
pupils

What is the initial surgical approach of
choice?
a) median sternotomy
b) right sided cervical incision
c) right sided clavicular incision
d) right anterolateral thoracotomy
e) left anterolateral thoracotomy
22yo female stab to left 5th ICS in MCL
 BP=70/40; HR=140; RR=35
 JVD-normal; trachea midline; muffled
HS; decreased BS on the left

Which of the following is/are possible
diagnosis?
a) pericardial tamponade
b) massive left hemo
c) tension ptx
d) flail chest
e) a, b, and c
28yo unrestrained driver in MVC
 VSS and LUQ tenderness with no
peritonitis

What is the next step in management?
a) ex lap
b) diagnostic peritoneal lavage (DPL)
c) admit for obs
d) CT abdo/pelvis
e) focused assessment using sonography
for trauma (FAST)
47yo male high speed MVC
 VSS, multiple rib fractures and L femur #
 PCXR (insert)

Which of the following is/are most
appropriate for evaluation?
a) admit, observe, repeat CXR 6-8 hrs.
b) immediate aortography
c) CT thorax with contrast
d) L anterolateral thoracotomy
e) b and c
Which of the following is/are indications
for emergent angiography in
hemodynamically unstable patients with
a pelvic ring fracture?
a) grossly negative findings on DPL
b) micro. positive findings
c) grossly negative findings on DPL and
continued bleeding requiring ongoing
transfusion
d) stable patient with an expanding hematomta
Regarding liver trauma, which of the
following statements is/are true?
a) NOM is Rx of choice in stable pt. with isolated hepatic
injury
b) the Pringle maneuver can be performed for up to 90
min. without ischemic sequelae
c) subcapsular hematomas discovered intraop should
always be explored
d) finger fracture technique for deep lacs is ineffective
e) intraop packing, rapid closure, and resuscitation in the
ICU has led to an increased mortality
27yo male suffers severe blow to head
 VSS, breathing spontaneously
 opens eyes to voice; mumbles words;
withdraws to pain

Which of the following is/are indicated in
the initial evaluation and stabilization?
a) CT head
b) ETT and hyperventilation
c) ICP monitoring
d) burrhole on the right side
e) A, B, C
Which of the following is/are true re:
peripheral arterial injuries?
a) all patients have diminished or no pulses
distal to the extremity
b) if the injury cannot be repaired primarily, a
prosthetic interposition graft should be used
c) all patients with post. knee dislocations should
undergo popliteal angio
d) compartment syndrome is a contraindication
to angiography
e) completion angio. is not necessary after the
insertion of an interposition graft if distal
pulses are present
Critical Care
Cardiac Physiology
PAWP ~ Left atrial pressure
 CVP ~ Right atrial pressure

Exams

Approaches to questions that give central pressure
data
 Is the heart working well?



If CO is low where is the problem



Use the cardiac index/cardiac output
If the CO is high look for distributive causes of shock
Look at where pressures are increasing
This is usually proximal to the disease
E.g. PE  high RV and CVP but normal wedge
Shock

Approach to a hypotensive patient

MAP = CO x SVR
Decreased Cardiac Output
Decreased SVR






Sepsis
Neurogenic Shock
Adrenal Insufficiency
Liver Failure
Anaphylaxis
Medications
Classifying Shock
Hypovolemic
 Cardiogenic
 Obstructive
 Distributive
 (Endocrine)


Can have cardiogenic or
distributive components

A 51 YO patient with known lung cancer undergoing
radiation therapy presents to the hospital with
worsening shortness of breath. He becomes
hypotensive and gets admitted to the ICU. He has a CI
of 1.9, CVP 20, PAWP 20, RV pressures 35/20 PA
pressures 32/20. What is the most likely diagnosis
PE
 MI
 Pneumonia and sepsis
 Cardiac Tamponade

Tamponade
Intrapericardial pressure equalizes
and opposes atrial and ventricular
pressures
 Hypotension, tachycardia, high CVP
and pulsus paradoxus (drop
>10mmHg in pressure with
inspiration)

Treatments
1. Which of the following is/are not a
determinant of CO?
a) end-diastolic pressure
b) afterload
c) contractility
d) heart rate
e) ventricular interaction
Key Equations
CO = HR x SV
SV = EDV – ESV
EF = SV / EDV
MAP = CO x SVR
Frank-Starling
2. Which of the following mechanisms are the body’s
most important defenses in severe oxygen transport
deficiency?
a) hyperventilation
b) reduction of VO2
c) organ redistribution of CO
d) shifting of the O2 dissociation curve
e) widening of the a-v O2 content

The oxyhemoglobin dissociation curve relates the
partial pressure of O2 in the blood (PO2) to the %
saturation of hemoglobin with oxygen (SO2). For a
given SO2, the PO2 depends on all of the following,
EXCEPT?
1)
2)
3)
4)
temperature
serum potassium
pH
RBC content of 2,3-DPG
Hemoglobin-O2 Dissocation Curve
Remembering the dissociation
curve

A shift to the right means
oxygen is unloaded
“Exercising muscle needs
oxygen”
Increased temp, CO2,
acidosis, glycolysis
 2,3 DPG is a glycolysis
breakdown product
Compare curves for a set pO2


3. What is the definition of the shock
state?
a) low BP to maintain normal metabolic and
nutritional metabolism
b) low CO to maintain normal metabolic and
nutritional metabolism
c) inadequate tissue perfusion to maintain
normal metabolic and nutritional metabolism
d) abnormal vascular resistance to maintain
normal metabolic and nutritional metabolism
DO2-VO2 Equations
4. In which of the following is CVP a
reliable guide in fluid management?
a) CXR with pulmonary edema
b) RVEDP = CVP
c) MV disease
d) LVEF = 0.4
e) PHTN
CVP and PCWP
5. Which of the following are determinant of
mixed venous O2 saturation (SvO2)?
a) VO2
b) CO
c) Hb Concentration
d) arterial O2 saturation
e) myocardial VO2
6. Which of the following is/are
associated with en elevated SvO2?
a) septic shock
b) distal migration of the PAC
c) lactic acidosis
d) left-to-right shunt
e) right-to-left shunt
7. Regarding CO2 kinetics, which of
the following is/are true?
a) total amount of CO2 produced is equivalent to
the total amount of O2 consumed
b) the a-v difference of CO2 is the same as O2
c) end-tidal CO2 is the same as paCO2
d) all of the above
CO2 metabolism
8. Which of the following is/are associated
with increased dead space ventilation?
a) low CO
b) ARDS
c) PE
d) PHTN
e) all of the above
9. With regards to ventilatory mechanics, which
of the following statements is/are true?
a) WOB consume 2% of total body O2 consumption
b) WOB may increase to 50% in the postop patient
c) the increased WOB in COPD is due primarily to an
increased inspiratory effort
d) airway pressure reflects the compliance of the chest
wall and diaphragm as well as the lungs
e) C = V / P
Compliance & Resistance
10. Which of the following indicates the
need for immediate ventilatory support?
a) RR > 35bpm
b) paCO2 >60mmHg
c) A-a O2 gradient > 350mmHg
d) VD/VT >0.6
e) shunt fraction greater than 5%
11. ARDS is characterized by:
a) bilateral pulmonary infiltrates
b) paO2/FiO2 <300mmHg
c) PCWP >18mmHg
d) hypoxemia with hypercarbia
e) increased dead space ventilation and
increased lung compliance
12. Which of the following treatment are
appropriate for the ARDS patient?
a) MV
b) albumin and Lasix
c) PEEP
d) ECMO
e) routine steroids
13. With regards to FRC, which of the
following is/are true?
a) FRC = RV + TV
b) atelectasis occurs when the FRC falls
below the closing volume (CV)
c) FRC = ERV + RV
d) FRC is increased by PEEP
PFTs
14. Which of the following may be
seen with shock?
a) hyperglycemia
b) negative nitrogen balance
c) lactic acidosis
d) metabolic alkalosis
e) hyperkalemia
15. 24yo female undergoes ex lap for a Class IV
hemorrhage and is transfused >12U PRBCs. Which of the
following is most appropriate?
a) CaCl
b) FFP
c) plt
d) correction of hypothermia
e) heparin
Questions?