PREGANCY changes Flashcards
Conducting airway
improve during pregancny
Dilation of larger airways occurs due to
Hormonal influences
Progesterone hormone goals
Direct dilation
Indirect by enhancing B2 activity
Pregnancy and Obesity
Restrictive
What decrease in Pregnancy in resp (ONLY ONE AFFECTED)
FRC Decreases
Airway dilatation compensates for the expected ↑ airway resistance due to
REASON is unknown
•
Hypocapnia
• Reduced resting lung volume
Hyperventilating can cause
increase airway resistanc
***•Lung volumes and capacities change during
pregnancy most importantly
FRC
Diaphragm goes
UP not a good thing
•FRC is reduced to 80% of pre-pregnancy values by
term
FRC There is a 20% reduction in FRC
• Accounted for by
- 25% reduction in ERV
* 15% RV reduction
No INDUCTION
to pregnant ladies
FRC is the gas tank of your lung
Storage, HIGHER –> BETTER
decreased FRC
quicker desaturation
Doesn’t change at all is
Vital capacity
Read table 2-2
and changes and percentage
SUPINE
worsens PRELOAD AND VENOUS RETURN
Changes in volume affect patients because you have
Less time to intubate
Early respiratory cahnges due to hormone initially and also later due to
CO2 production
Progesterone
INCREASE SeNSItiVity of CENTRAL CHEMORECEPTORS to CO2
Bicarb
Increase pH
Ph in mother is
SLIGHLY ALKALOTIC
Metabolic alkalosis
reduces Co2 and Bicarb to 20
• PaO2 ↑ to 107 mmHg in first trimester due to•
↑ CO greater than O2 consumption
• As O2 consumption progresses in 2-3 trimester, the A-V
difference
↑ and PaO2 falls
• Supine position decreases PaO2 by
- Reducing FRC
- Closing small airways
- ↑ shunt
- Reducing cardiac output (CO) via aortocaval compression ↑↓
Metabolism & Respiration during Labor
•
Pain during labor
• MV ↑ 70-140% by time of delivery
• MV ↑ 120-200% first and second stages
• PaCO2 may fall to 10-15 mm Hg • O2 consumption ↑ by 40% first stage • O2 consumption ↑ by 75% second stage • Due mostly due to - hyperventilation work 50% • Uterine activity • Maternal expulsive methods • Demand outstrips O2 supply- go anaerobic
***• FRC ↑ but below normal up until
1-2wks postpartum
• Up to six week (
- ↑ O2 consumption
- ↑ TV
- ↑ MV
***CO highest
Immediately AFTER you deliver the baby
must compensate for AV fistula
Placenta
Increase in blood volum
Increase cardiac work
heart musts hypertropy lifting more fluid
Increase in blood volume
Increase cardiac work
heart musts hypertropy lifting more fluid
PRESENT IN 94% OF PREGNANT PATIENT
TRICUSPID REGURGITATION
• ↑ pulmonary resistance
↑ right ventricular pressure
• ↑ risk for pulmonic valve insufficiency
• ↑ risk for TR
• ↑ blood volume
↑ cardiac workload
• ↑ risk of developing LVH
• ↑ risk of MR
• ↓ viscosity and AV fistula lowers SVR
• Low risk for Aortic valve dysfunctioN
• The heart shifts anteriorly and to the left due
to
diaphragmatic elevation
• Grade I-II systolic murmur is typically
heard;
usually TR or MR
EKG shows
sinus tachycardia with a short PR
• Echo
- Elevated pulmonary pressures
- Pulmonary insufficiency
- Annular dilations
- 94% have TR
- 27% have MR
- Confirms LVH
- Aortic valve not affected
KNOW TABLE
2-4
↑ in CO by \_\_\_\_\_ • Organs with ↑ perfusion •\_\_\_\_\_ -\_\_\_\_\_\_\_ • \_\_\_\_ GFR by \_\_\_\_\_\_\_\_\_\_ • ↑ to remove \_\_\_\_\_\_\_\_\_\_ • Extremities • Skin • ↑ skin temp • Skeletal muscle • Other major organs are unaffected
↑ in CO by 2 L/min • Organs with ↑ perfusion • Uterus • Kidneys • ↑ GFR by 900% at time of delivery • ↑ to remove ↑ waste products • Extremities • Skin • ↑ skin temp • Skeletal muscle • Other major organs are unaffected
3 ORGANS THAT REALLY BENEFIT FROM BLOOD FLOW INCREASE
UTERUS
KIDNEY
EXTREMITIES
PREGANT PATIENT WITH LOW BP
VOMITING
BP Changes
•BP varies with position, age and parity •BP higher when supine • •Advanced age and nulliparity have higher mean pressures than younger/parous woman •Systolic pressure typically unaffected •Diastolic pressure lowers 20 to low resistance vascular bed (intervillous space) and hormonally induced vasodilation
BP lower when
- Sitting
- Standing
- lateral
BP Changes
•BP varies with position, age and parity •BP higher when supine •Systolic pressure typically unaffected •Diastolic pressure lowers 20 to low resistance vascular bed (intervillous space) and hormonally induced vasodilation
•Advanced age and nulliparity have______ mean
pressures than younger/parous woman
higher
NULLIPARITY
FIRST TIME HAVING BABY
WIDENING PULSE PRESSURE
PREGANCY
SBP INCREASE, DBP SAYS THE SAME.
Supine Position
- Caval compression occurs as early as 13-16 wks
- ↑ femoral venous pressure
- At term femoral venous pressures are 2.5x normal due to caval obstruction
- Collaterals cannot maintain venous return so right heart pressures fall
- Aorta is partially obstructed
• Lateral Decubitus Position
- Partial caval obstruction
- Collaterals maintain venous return
- Intraosseous vertebral veins
- Paravertebral veins
- Epidural venous plexus
- Aorta is unaffected (lateral tilt position has 40% aorta compression)
- ↓ preload (10-20%)
* Uterine blood
- SV decreases
* CO decreases
LEFT LATERAL TILT AORTA IS
NOT AFFECTED
RIGHT AFTR SPINAL
PUT SOMETHING UNDER RIGHT HIP
Aortocaval Compression
•
↓ preload (10-20%) • SV decreases • CO decreases •Uterine blood flow falls by 20% •Lower extremity blood flow falls by 50% • ~8% of woman experience bradycardia and substantial hypotension in the supine position • “SUPINE HYPOTENSIVE SYNDROME” • results from the profound drop in venous return from which the CV system cannot compensate
Total blood volume ↑ by
• 1st trimester ___%
• 2nd trimester ___%
• 3rd trimester ____%
____%
_____%
_____%
• Erythropoietin is ↑ ↑ the RBC production
“Dilutional Anemia”
• Hgb falls to ~11.2-11.6 g/dl
Hemodilution helps maintain the uteroplacental vascular bed and minimize
• ↑
thrombosis/infarction
maternal survival
KNOW
HORMONLA EFFECT ON PLASMA VOLUM
KNOW
HORMONAL EFFECT ON PLASMA VOLUME
PLASMA CHOLINESTERASE
BY 25%
PLASMA CHOLINESTERASE
BY 25%, needs less succynilcholine
Coagustion
• A state of accelerated but compensated intravascular coagulation • Elevated platelet • Activation • Consumption • Aggregation • Production also enhanced ----- Except ~7-8% parturients have platelet count <150,000 • Clotting factor concentrations are ↑ • shortened PT/PTT by 20% • Decreases in antithrombin III • Pregnancy is a “hypercoagulable state” • Fibrinolysis enhanced • See ↑ fibrin degradation products and plasminoge
Platelet count
LESS than 75 do not do spinal
Antithromobin III
Decreases, HYPERCOAGULABLE STATE
Antithromobin III
Decreases leading to HYPERCOAGULABLE STATE
EBL NVD
500-600
EBL C secion
about 1L
Hematology and coagulation Puerpirium
Hgb coung falls
protein concentration falls
GI
Lower LES
GI
Assume GERD
Lower LES tone
Fasting Gatric volume and pH
are normalized by 18 hours
Impaired gastric emptying
ASSOCIATED WITH OPIOIDS
LACTOGEN
HORMONAR
Thyroid
Increase t3 and T4
Worse for spinal and epidural
LORDOSIS
Increase FORGETFUL due to
PROGEsterone (
Once you’re done with SPINAL, put patinet in LATERAL TILT POSITION given this med IM to prevent Hypotension
1 cc/ 50 mg
Draw it up in saline, IM 50 mg
Epidural
17 inch needle, long
Below
Regional
STOP if there is contraction
if you keep going, they are tense and they are moving.
Epidural
BLOOD PATCH , Headaches do not go away
BUPIVICAINE IV (CONTRAINDICATED)
Cardiac arrest
Test dose of epidural
LIDOCAINE with a litte epinephrine
LEFT LATERAL TILT
Before you do anesthesia.
MAC is reduced by
30%
MAC reduced due to
Progesterone
CNS serotonic activity
Take home message for succ
GIve less
Pregnant and CSF
Less CSF
C3, C4, C5
phrenic nrve
KEeps them alive
C6 be t
C with fingers
