Transcript DR.Mohr-HypoxiaLecture_000

Hypoxia, Respiratory
Failure and Altered Mental
Status
Alicia M. Mohr, MD
Surgical Fundamentals Session 2
July 21, 2006
Objectives
• To learn a logical method for determining the
nature of respiratory failure and its treatment
• To determine if a patient requires intubation and
ventilation
• To learn the differential diagnosis and treatment
of altered mental status
Labs & ABG normal
History and Physical Exam
Diagnosis
Operation performed
Co-Morbidities
Age
Remains agitated
and risk for withdrawal
(alcohol +/or drug)
Consider need for CTH
Intubated
Re-intubate
ETT
dislodged
Step 1
Assess Airway
Sa02 > 90%
Not intubated
ASSESS
PATIENT
Pulse Oximetry
Check CXR
(go to step 2)
ETT
good position
Mini-neuro exam
Review chart for
medications
Call for
Altered Mental Status
Desaturation or
Respiratory distress
May sedate with
Short-acting
benzodiazepine or haldol
Sa02 < 90%
Step 2
Assess Breathing
intubate
Hemodynamically
stable
Check
CXR, ABG
Hemodynamically
unstable with
 breath sounds
Chest X-ray
Lab
Electrolytes
Arterial Blood Gass
Step 3
Assess Circulation
Tube
thoracostomy
Pulses absent
ACLS protocol
Pulses present
Assess cardiac
status- ie.
arrythmias
History
History
•
•
•
•
Can’t catch my breath
Lightedheadedness
Usually acute onset
Minimal symptoms
Physical Exam Findings
Physical Exam Findings
•
•
•
•
•
•
•
•
Tachypnea
Dyspnea
Retractions
Nasal flaring
Grunting
Diaphoresis
Tachycardia
Hypertension
• Altered mental status




Confusion
Agitation
Restlessness
Somnolence
• Cyanosis (need 5mg/dl
of unoxygenated blood)
Case Study #1
59 year old man underwent a Whipple two
days ago. You are called because he
developed a sudden onset of dyspnea and he
desaturated.
His temp is 37.3o, his HR is 120, RR 24 and
BP 80/50.
He is anxious with decreased breath sounds at
bilateral bases.
A - Airway
Oxygen delivery
to tissues
B - Breathing
C - Circulation
Carbon
dioxide
removal from
tissues
Assess, change, reassess
Case Study #1
Signs of respiratory distress
Nasal flaring
Sternal retractions
Tripoding
Use of accessory muscles
Tachypnea
Cyanotic
Anxiety, restlessness
Case Study #1
• His CBC and lytes are normal
• ABG pH 7.45 PaCO2 28 mmHg PaO2 72 mmHg
• CXR shows mild left lower lobe atelectasis
Indications for Intubation
Indications for Intubation
1.
2.
3.
Airway protection
Loss of gag reflex, GCS <8
Massive facial trauma
Failure to ventilate
Increased work of breathing
PaCO2 > 55 mm Hg
Failure to oxygenate
Hypoxemia or PaO2 < 60 mm Hg
Severe metabolic acidosis or shock
Need for bronchopulmonary toilet
Indications for Intubation
•The decision to intubate or not intubate a patient
can be a life or death decision
•It should not be taken lightly!
•However, most times you will ask yourself-’Have
you ever regretted intubating a patient?’
•The most likely response is that you have
regretted NOT intubating a patient
•IF YOU THINK ABOUT INTUBATING A PATIENT
YOU SHOULD PROBABLY DO IT!
Rapid Sequence Intubation
Establish IV
Preoxygenate patient
Apply cricoid pressure
Administer etomidate 0.3 mg/kg IV
Administer succinylcholine 1.5 mg/kg IV
CAVEAT: For most
emergent intubations
medications are not
required or not available!
INTUBATE
Do not release cricoid pressure until cuff
inflated and tube placement verified
Auscultate bilaterally to verify tube placement
Use CO2 detector to assure tube placement
Secure endotracheal tube
Case Study #1
• His CBC and lytes are normal
• ABG pH 7.45 PaCO2 28 mmHg PaO2 72 mmHg
• CXR shows mild left lower lobe atelectasis
Pathophysiology
of Respiratory
Failure
Due to mismatch of
ventilation and
perfusion in lung
units
Labs & ABG normal
History and Physical Exam
Diagnosis
Operation performed
Co-Morbidities
Age
Remains agitated
and risk for withdrawal
(alcohol +/or drug)
Consider need for CTH
Call for
Altered Mental Status
Desaturation or
Respiratory distress
Intubated
Step 1
Assess Airway
Sa02 < 90%
Step 2
Assess Breathing
Re-intubate
ETT
dislodged
Not intubated
ASSESS
PATIENT
Pulse Oximetry
Check CXR
(go to step 2)
ETT
good position
Mini-neuro exam
Review chart for
medications
Sa02 > 90%
May sedate with
Short-acting
benzodiazepine or haldol
intubate
Hemodynamically
stable
Check
CXR, ABG
Hemodynamically
unstable with
 breath sounds
Chest X-ray
Lab
Electrolytes
Arterial Blood Gass
Step 3
Assess Circulation
Tube
thoracostomy
Pulses absent
ACLS protocol
Pulses present
Assess cardiac
status- ie.
arrythmias
Case Study #2
22 year old man was admitted five days ago
after an MVC. He sustained a left rib fractures,
a left pneumothorax and a left femur fracture.
The nurse states the patient is short of breath.
His temp is 37.1o, his HR is 95, RR 30 and BP
120/70.
His saturation on room air is 85%
Differential Diagnosis
Differential Diagnosis
•
•
•
•
Pneumothorax
Pneumonia
Lobar collapse
Pulmonary embolus
Case study #2
• When the situation is not life threatening there is
ample time to perform the necessary diagnostic
tests and manuevers
• In a life threatening situation immediate action is
necessary to prevent arrest
• For example, if you suspect someone has
a tension pneumothorax as a life saving
manuever you should perform needle
decompression with a 14 gauge angiocath
rather than wait for a tube thoracostomy
and scalpel, etc.
Labs & ABG normal
History and Physical Exam
Diagnosis
Operation performed
Co-Morbidities
Age
Remains agitated
and risk for withdrawal
(alcohol +/or drug)
Consider need for CTH
Call for
Altered Mental Status
Desaturation or
Respiratory distress
Chest X-ray
Lab
Electrolytes
Arterial Blood Gass
Check CXR
(go to step 2)
ETT
good position
Mini-neuro exam
Review chart for
medications
Sa02 > 90%
May sedate with
Short-acting
benzodiazepine or haldol
Intubated
Step 1
Assess Airway
Re-intubate
ETT
dislodged
Not intubated
ASSESS
PATIENT
intubate
Hemodynamically
stable
Pulse Oximetry
Sa02 < 90%
Step 2
Assess Breathing
Step 3
Assess Circulation
Hemodynamically
unstable with
 breath sounds
Check
CXR, ABG
Tube
thoracostomy
Pulses absent
ACLS protocol
Pulses present
Assess cardiac
status- ie.
arrythmias
Case Study #3
72 year old man was admitted two days ago
after an assault. He sustained an orbital
fracture, scalp laceration and a frontal
contusion. The nurse states the patient is
confused and restless.
Case Study #3
What do you want to know?
• Is this a change in his mental status?
• Was he just medicated?
• Has this happened before?
• What are his vital signs?
• What is his saturation?
Altered Mental Status
Five major causes:
• Metabolic derangement
• Drug toxicity/overdose/withdrawal
• Infectious
• Strutural abnormality
• Psychiatric
Altered Mental Status
Metabolic abnormality
• Rule out hypoxia
» Check ABG, saturation
• Rule out hypoglycemia, DKA
» Assess blood glucose
• Rule out uremia
» Assess urine output, BUN, creatinine
• Rule out hepatic encephalopathy
» Check ammonia
• Rule electrolyte abnormalities
» Send electrolytes
Altered Mental Status
Structural abnormality
• Assess GCS
• Assess for suspected head injury
• Assess for focal neurologic deficits
• Assess for possible post-ictal state
• Emergent CT head
Altered Mental Status
Infectious cause
• Assess for post operative sepsis
• Assess risk of meningitis
• Assess need for CT
Altered Mental Status
Drug toxicity/overdose/withdrawal
• Assess recent prescribed medications
• Assess for potential self prescribed
medications
• Check pupils
• Check for sweating, agitation, hallucinations
• Assess HR and blood pressure
• May prescribe narcan or naloxone if OD
• May prescribe benzodiazepine if withdrawal
Altered Mental Status
Altered Mental Status
Psychiatric cause
• Assess for hallucinations
• Assess for delusions
• Mini-neuro exam
Labs & ABG normal
History and Physical Exam
Diagnosis
Operation performed
Co-Morbidities
Age
Remains agitated
and risk for withdrawal
(alcohol +/or drug)
Consider need for CTH
Intubated
Re-intubate
ETT
dislodged
Step 1
Assess Airway
Sa02 > 90%
Not intubated
ASSESS
PATIENT
Pulse Oximetry
Check CXR
(go to step 2)
ETT
good position
Mini-neuro exam
Review chart for
medications
Call for
Altered Mental Status
Desaturation or
Respiratory distress
May sedate with
Short-acting
benzodiazepine or haldol
Sa02 < 90%
Step 2
Assess Breathing
intubate
Hemodynamically
stable
Check
CXR, ABG
Hemodynamically
unstable with
 breath sounds
Chest X-ray
Lab
Electrolytes
Arterial Blood Gass
Step 3
Assess Circulation
Tube
thoracostomy
Pulses absent
ACLS protocol
Pulses present
Assess cardiac
status- ie.
arrythmias
Case Study #4
70 year old female had a colon resection five
days ago. You are called by the nurse because
she is dyspneic.
Her temp is 100o, her RR is 30, her HR is 110,
and her BP is 140/90.
Her saturation is 95% on a non-rebreather.
Differential Diagnosis
Differential Diagnosis
•
•
•
•
•
•
•
•
Pneumonia
Lobar collapse
Pulmonary embolus
Aspiration
Sepsis
Pulmonary edema
Congestive heart failure
Myocardial infarction
Case Study #4
Causes of post-operative dyspnea
• Rule out pneumonia, atelectasis, collapse, aspiration
» Check ABG, saturation, CXR
» Assess abdomen, need for NGT
• Rule out sepsis
» Assess for fever, abdominal exam, CTA/P
• Rule out pulmonary embolus
» Assess leg swelling, duplex, CT chest
» Can heparin be started empirically?
• Rule out myocardial infarction
» Check EKG, troponin, myocardial enzymes
» Can aspirin be given?
• Rule out fluid overload, CHF
» Listen to lungs, assess fluid balance
» Check home medications
» Give diuretic
Case Study #4
Does this patient need to be moved to monitored bed
or ICU?
• Does this patient require intubation now?
• May this patient need to be intubated in the
next few hours?
• How likely is it that the patient is having an
MI?
• Is the patient having an arrythmia?
• Does the patient need invasive monitoring?
• How likely is it that the patient is going to
decompensate?
• How likely is it that I am going to be presenting
this at M&M?
Criteria for ICU assessment
Threatened airway
Respiratory arrest
Respiratory rate >30 or <8 breaths / min
Oxygen saturation <90% on >50% oxygen
Cardiac arrest
Pulse rate <60 or >140 beats / min
Systolic blood pressure < 90 mmHg
Sudden fall in level of consciousness
Repeated or prolonged seizures
Rising arterial carbon dioxide tension with respiratory acidosis
Case Study #5
45 year old male in the ICU admitted four days ago
with necrotizing pancreatitis. He was intubated on
admission. His current ventilator settings are IMV rate
of 14, tidal volume 600 mL, PEEP 5 and FiO2 50%.
The nurse calls you because after the patient was
turned and washed he desaturated to 70%.
She has already turned the FiO2 up to 100% and his
saturation has not responded.
Differential Diagnosis
Differential Diagnosis
•
•
•
•
•
•
•
•
•
•
Pneumonia
Lobar collapse
Pneumothorax
Pulmonary embolus
Aspiration
Sepsis
Pulmonary edema
Mucous plugging
Bronchospasm
ETT is dislodged
What do you do?
• Take patient off the ventilator and hand bag
» Rule out ventilator problem
» Assess degree of airway resistance
• Listen to the lungs
» Rule out pneumothorax, fluid overload, bronchospasm
• Order a CXR, ABG
» ABG will be bad, but will assess acidosis, and
ventilation
» CXR will assess ETT placement, lobar collapse,
effusion, pneumonia, etc.
» Does patient require bronchoscopy?
• Pass a suction catheter
» Rule out an occluded, dislodged ETT and assess
secretions
• Give a bronchodilator
» Can’t hurt! May loosen secretions
• If chest tubes in place, make sure on suction and assess for air leak
• Adjust ventilator to compensate worsening respiratory failure
Labs & ABG normal
History and Physical Exam
Diagnosis
Operation performed
Co-Morbidities
Age
Remains agitated
and risk for withdrawal
(alcohol +/or drug)
Consider need for CTH
Intubated
Re-intubate
ETT
dislodged
Step 1
Assess Airway
Sa02 > 90%
Not intubated
ASSESS
PATIENT
Pulse Oximetry
Check CXR
(go to step 2)
ETT
good position
Mini-neuro exam
Review chart for
medications
Call for
Altered Mental Status
Desaturation or
Respiratory distress
May sedate with
Short-acting
benzodiazepine or haldol
Sa02 < 90%
Step 2
Assess Breathing
intubate
Hemodynamically
stable
Check
CXR, ABG
Hemodynamically
unstable with
 breath sounds
Chest X-ray
Lab
Electrolytes
Arterial Blood Gass
Step 3
Assess Circulation
Tube
thoracostomy
Pulses absent
ACLS protocol
Pulses present
Assess cardiac
status- ie.
arrythmias
ARDS
• A patient must meet all of the following:
– Acute onset of respiratory symptoms
– CXR with bilateral infiltrates
– No evidence of left heart failure
– PaO2/FiO2 < 200mm Hg (regardless of PEEP)
– American-European Consensus Conference on ARDS (Am J
Resp Crit Care Med 149:818, 1994)
• The following are implied:
– Previously normal lungs
– Decreased lung compliance
– Increased shunting
– Hypoxemic respiratory failure