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Flashcards in Equations and Fun Facts Deck (15):

Maximum heart rate



Target blood pressure for hypertensive patients

135/85 unless they have renal disease or diabetes in which 130/80 is the goal


lung cancer associated with pancoast tumors

Squamous cell carcinoma


3 procedures you should obtain a CXR after

1. transthoracic needle aspiration
2. thorancentesis
3. central line placement

Due to risk of pneumothorax


Acute respiratory failure definition

Hypoxia: PaO2 less than 60 mmHg and PaCO2 greater than 50 mmHg
Hypercapnia: partial pressure of CO2 greater than 50 mmHg


Ventilation vs oxygenation

To decrease PaCO2 one must increase RR or increase tidal volume

Oxygenation=O2 saturation and PaO2
To decrease PaO2 in ventilated patient one must decrease FiO2 or decrease PEEP


Hypoxemic Respiratory Failure

Low PaO2 with normal or low PaCO2
O2 is less than 90% despite FiO2 greater than .6

Causes: ARDS, pneumonia, pulmonary edema
V/Q mismatch-responsive to O2
intrapulmonary shunting-atelectasis or fluid buildup in alveoli
not responsive to supplemental O2


Hypercarbic respiratory failure

High PaCO2
Due to decreased minute ventilation or increase in physiological dead space

Causes: COPD, asthma, CF, severe bronchitis
CNS depression, neuromuscular diseases, respiratory fatigue
DKA, Sepsis and hyperthermia-increased CO2 production


Indications for mechanical ventilation

Significant respiratory distress high RR or respiratory arrest
Impaired or reduced level of consciousness with absent gag or cough reflex
Metabolic acidosis
Respiratory muscle fatigue
Significant hypoxemia (PaO2 less than 70)
Or hypercapnia (PaCO2 greater than 50)
Respiratory acidosis: ph less than 7.2 with hypercapnia


Parameters of ventilation

Minute Ventilation: 10-12 breaths per minute
FiO2: start at 100% quickly titrate down to maintain PaO2 of 50-60 or O2 saturation greater than 90% (can add PEEP or CPAP to reduce FiO2) less than 60% is safe
I:E ratio: 1:2 is normally used
PEEP: 2.5 cm to 10 cm H2O is the appropiate initial seeting


Amount of time you must be abstinent from alcohol to receive liver transplantation in cirrhosis

6 months


green/yellow vs. brown vs black gallstones

yellow/green: (cholesterol stones)obesity, diabetes, hyperlipidemia, multiple pregnancies, oral contraceptive use, chron's disease, ileal resection, advanced age, native americans, cirrhosis, cystic firbrosis

Brown: biliary tract infection

Black: hemolysis or alcoholic cirrhosis


Calculation of maintenance fluids

100/50/20 rule
100 for first 10 kg, 50 for second 10 kg, 20 for each 10 kg after that, divided by 24
70 kg man=100x10=1,000, 50 x 10=500, 20 x50=1,000
2,500=total/24=104 ml/hr


4/2/1 rule
4 ml for first 10 kg, 2 for second 10 and 1 for each kg over 20
70 kg=40+20+50=110 ml/hr


ionized calcium equation

total calcium-(serum albumin x.8)


LDL cholesterol equation

Total cholesterol-HDL-TG/5