The Pregnant Patient

7/21/2019 The Pregnant Patient

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Santa Rosa Hospital

Sheila Sustache de Leon MD

Enero 2012

THE PREGNANT PATIENT

Santa Rosa Hospital

Sheila M. Sustache de Leon MD

Feb/ 2012



• Full term delivery at 37 week

of gestation.

• 12% of live births are

premature.

• 65% of all perinatal morbidity

and mortality is associated

with premature delivery.



Non pregnant

• Uterus weight

– 70g

• Cavity volume

– 10ml

pregnant

• Uterus weight

– 1100g

• Cavity volume

– 5 L



Extends Abdominal cavity

umbilicus

liver



• Exerts pressure on the anterior abdominal wall.

– Displaces the intestine superiorly and laterally.

•

Change the relationship between the abdominal visceralorgans.

• In upright position

– The uterus is supported by the anterior abdominal

wall. – Usually undergoes a dextrorotation because of the

presence of the rectosigmoid on the left.

• In supine position

– Uterine weight falls on the spinal column. – Compression of the surrounding great vessels.

– Especially the flaccid IVA





• Electrical change in the myometrium

– Resting membrane potential of the uterine

myocyte ranges from -40 to -60 mV.

– Early in gestation

• -60mV

• Irregular electrical activity (slow waves)

–Near term• -40 mV



• Rhythmic alteration in the membrane

potential lead to an action potential at the top

of slow waves.

Entry Ca2+Voltage sensitiveCa2+ channel

Allow interaction

actin-myosin

Electromechanicalcoupling

Uterinecontraction



• Second trimester

– Irregular contraction can be palpated though the

abdominal wall (Braxton hicks contractions)

• Irregular in intensity

• Infrequent

• Unpredictable

•

Non-rhythmic• More uncomfortable than painful)

• They do not increase in intensity, or frequency



http://www.medhelp.org

• Small increase uterine pressure up to 80 mmHg.

•Increase gap junctions results in rapid and efficient

conduction of the action potential uterine smoothmuscle.

•Resulting coordinated

•Dilatation of cervix and delivery of the baby.



Stimulates uterine

activity

Down regulates uterine

activity

Estrogen (opposing the action of

progesterone)

Progesterone (block Ca2+ flux

thought cell membrane)

Oxytocin ( secreted from posterior

pituitary. Stimulate Ca2+ across

myometrial plasma membrane anddistinct receptor myometrium and

other reproductive tissues.)

PGE₂, PGFα (favor activation of

the uterine musculature, onset uterine

contraction. Raise local [Ca2+] byincreasing release from intracellular

store. )

IL-1, IL-6 (produced locally by

placental tissue and act in concert with

other stimulatory factor)



• Multifactorial

– Surgical manipulation

– Intraabdominal inflammatory process



• The delaying or inhibition of labor stopping of

contraction during premature labor.

– Intervention is directed at decreasing the uterine

smooth muscle activity thought inhibition of themuscle contraction.

– Tocolytic treatment may result in the delay of delivery

by aprox. 48 hrs, which allows for the administration

of steroids to promote fetal lung maturation.• Decrease risk of respiratory distress syndrome and

multiorgan failure in the preterm neonate.



• Magnesium sulfate

– First line tocolytic agent

– High intracellular [Mg] inhibits Ca2+ entry

myometrial cells interfering with actin-myosin

coupling. Also increase the sensitivity of K+

channels favoring hyperpolarization and uterinerelaxation.

– Range 4 and 9 mg/dL



• Prostaglandins

– Prostaglandin synthetase inhibitors specially

AINES are use to stop premature labor.

• Indomethacin

– Recomendated in Nonobstetric surgery.

– Preoperative dose 50mg-100 mg PO

– Postoperative 50 mg PO q 6 hrs for 48hrs.

– Intraabdominal surgery preterm pregnant» Two doses of betamethasone 12mg 24hrs or four doses of

dexamethasone 6 mg 12 hrs

» Ideally beginning 48 hrs prior to surgery.



• Β adrenergic agonists

– Stimulation of uterine β2 receptor leads to activationof adenylate cyclase and an increse in intracellularcyclic adenosine monophosphate (cAMP)concentration.

– Activation of cAMP dependent protin kinase A inhibitsmyosin light chain phosphorylation and actin myosincoupling.

– Protein Kinase A activity is also associate with increaseCa2+ effux, decrease Ca2+ influx, and increases K+conductance.



• Calcium channel blockers

– Inhibits entry of calcium though voltage

dependent Ca2+ channels.

• Nifedipine

– Abolish uterine activity and prevent delivery with minimal

toxicity or side effects.



• The maternal physiologic homeostasis adapts in

order to promote a physiologic environment the

benefits the development and growth of the

fetus.



• Progesterone levels increase

– Is a smooth muscle relaxant that play a major role

in assuring relaxation of the uterine smooth

muscle to prevent premature delivery.

– In addition vascular, gastrointestinal and

urogenital smooth muscle relaxes.





– Common clinical signs and symptoms associated

with this increase in CO and associated

vasodilatation include:• Decrease exercise tolerance

• Mild peripheral edema

• Spider angiomata

• Complains of stuffy sinuse

• Increase in lower extremity varicosities

• hemorrhoids

i O2 d li h f d



• To increase O2 delivery to the fetus and

remove the increased supply of CO2 produced

by the fetus.

– Hyperventilates

– Maternal O2 metabolism increases by 20% - 30%

and functional reserve capacity decrease.



• When intubation is needed, there significantly

less time to establish an airway and assure

continued oxygenation.

• Is common to have sensation of SOB,

specifically in the second and third trimester.



• The lower esophageal

sphincter tone gradually

decreases.

–

Nausea and vomiting ofpregnancy is a common

occurrence affecting

between 50% and 90%

of all women.



• The gallbladder empties more slowly during

pregnancy and undergoes a gradual increase

in residual volume, both during fasting andafter meals.

– Motility and volumes return to normal as early as

2 weeks after pregnancy.



• Prolonged small bowel transit time and

decreased colonic emptying work to maximize

nutrient and water absorption. – Contribute to the constipation reported by 38% of

pregnant women.



• Abdominal pain

– Round ligament pain is described as an aching,

dragging pain.

• Typically unilateral

• Provoked by physical activity or even turning while sleeping.

• Common occurrence third trimester

–

Pain in the hypochondrium.• Can result from uterine pressure on the lower ribs.

• Px describes a very localizated, sharp, nonradiating pain.

• That more often is on R+ compare to the L+ upper cuadrant.



• Hemoglobin concentrations may drop to 10

mg/dl.

• Hematocrit values may go as low as 30%.

• Pregnancy may be associated with an increase

in the WBC count.

– Up to levels of 13,000 cell/mL.

– Intrapartum and immediate postpartum (<24 hrs)

counts may be as high as 25,000 WBC/mL



•

Platelet count may slightly decrease as thepregnancy progresses.

– Up 8% of pregnancy

– The most common cause is gestational

thrombocytopenia.

• Typically asymptomatic

• Recover to normal levels a few weeks following the

delivery.



• Renal blood flow and glomerular filtration rateincrease by over 50%.

• Creatinine levels decrease appropriately, resultingin normal levels of 0.5 to 0.6 mg/mL.

• Serum alkaline phosphatase levels gradually

increase. – Because of production of an alkaline phosphataseisozyme by the placenta.

• Albumin levels may be lower. – Associated with the increase in plasma volumen and

osmotic pressure may be decreased.



• In almost all clinical presentations, the risks of

misdiagnosis by avoiding the proper imaging

tests are greater compared to the risks of

sequelae from ionizing radiation to the fetus.



• Ionizing radiation

– Fetal effects of ionizing radiation depend on the doseabsorbed by the fetal tissue and the stage of fetaldevelopment during exposure.

– The roentgen is a common unit of exposure.

• Produce 0.26 milicoulomb/kg of air or 2 billon ion pairs/ cm³ ofexposed air.

– One gray (Gy) is strictly defined as the deposition of 1.0 joule of energy/kg of tissue.

– One rad is 1% of 1 Gy.



– In is a misconception to assume that the radiationabsorbed by the mother is the same as the

absorbed by the fetus. – Dosing of radiation to the uterus and conceptus

can vary several fold based on abdominal walldepth and the anteverted or retroverted position

of the uterus. – DNA damage may be repaired of may result in cell

death, rapid cell growth, abnormal cell growth orgenetic mutation.

R di i d i h



Radiation dosing to the conceptus an

uterus from selected radiographic

examinations.Examination DOSE (mrad)

Routine Chest x- ray 0.5-1.0

Abdominal flat plate 140Intravenous pyelogram 78

CT, chest (uterus shielded, not

exposed)

16-23

CT, abdomen (uterus shielded,

not exposed)

150-190

CT, pelvis 2,000



• Growth impairment of organs occurs of the

population of cells cannot be replaced or

damage occurs to a small population of

progenitor cells at a vital stage ofdevelopment.



–

The outcome of radiation exposure depends onthe absorbed dose and the stage of development

during exposure.

• Potential death early in gestation.

• Teratogenesis during organogenesis (4 to 10 weeks ofgestation).

• Growth retardation at later gestational stages.



•

Lethal Effects – Multicellular embryo, before the blastocyst stage

is most sensitive to the lethal effects of radiationbut resistant to teratogenesis if it survives.

– More than 50% of all human pregnancies abort.• Determining the lethal dose of radiation at this stage is

difficult.

– Significant radiation exposure in the first 2 weeks

of human development.• 3 and 4 weeks of results in loss of the pregnancy.



• Teratogenic effects

–

Occurs during early organogenesis. – Correspond to weeks 2 to 8 in human

development (4 to 10 of gestation).

– A significantly higher rate after exposure to

radiation in pregnancy have been report:• Microcephaly, pigmentary changes in the retina,

hydrocephalus, and optic nerve atrophy.

– Exposure less than 5 rads does not increase the

risk for birth defects.• 5 to 10 rads = teratogenicity

• Greater than 10 rads = serious risk to the fetus.



• Intrauterine Growth restriction

– Result from radiation induced cellular depletion. – Example: children exposed in utero to the

Japanese atomic blasts.

• 1,500 m from center of the explosion

– Exposed to over 25 rads

– 2 a 3 cm shorter, 3 kg lighter head circumference 1 cm smaller

than normal (17 y/o)



• Oncogenic potential

– The correlation between childhood cancer and inutero exposure to radiation has been reported.

• Ultrasound

– Ultrasonography use high frecuency, no ionizing,acoustic radiation to create images.

– Audible sound range = 20 to 20,000 vibration/seg

• Ultrasonography use frecuencies of 1 millon to 10 millonsvibrations/seg

– Not been shown to produce fetal damage or harmfuleffect.

R id i d d i f



• Rapid compression and decompression of

tissue by sound wave. Cause tissue damage.

– Conversion of mechanical energy to thermal

energy.

– Especially at the bone soft tissue interface, could

lead to local hypertermia.

• CAVITATION could cause microscopic bubbles alreadypresent in tissue to grow size because of absorption of

surrounding diffused gases.



• MRI

– Use no ionizing radiation and relies on the magnetic

properties of tissue to create images. – Four magnetic fields interact during an MRI

examination to create the image.

• Intrinsic magnetic field (2)

• Extrinsic magnetic field (2)

– Present danger to the developing fetus.

• Charged particles and molecules moving in a strongmagnetic field create an electroestatic potential differenceand anormal RBC can alter their shape and create a charge

when moving within an electric field.• Can induce visual light flashes because of magnetic effects

on the photoreceptors in the eye, and heat can be generatedduring the application of radiofrequencies.

http://www.mrimagingblog.com/wp-content/uploads/2008/11/mri-diagram.png







– Elective examination of pregnant women by MRI postponeduntil after the first trimester and completion of organogenesis.

• Is not absolutely contraindicated.

• Medication in pregnancy – Medications contraindicated in pregnancy include but are not

limited:• Coumarin derivatives

• Isotretinoin

• Metrotrexate• Diethylstibestrol

• Thalidomide

• Angiotensin converting enzyme (ACE) inhibitors

• ACE antagonist

•

Tetracycline• Quinolones

– The risks to the fetus may be less compared to the risk to themother when not using the proper medication.



Fetal monitoring

•Fetal heart rate (FHR) Indirect assessment of fetalwell being.

• Can be monitored externally using Doppler

device that is placed on the maternal abdomen.• Uterine activity is monitored by using a

tocodynometer, also applied to the maternal

abdomen.

• Response to altered uterine-placental perfusion

or decrease O2 content in maternal blood.







• FHR interpretation – Fetal tachicardia ≥ 10 min ↑ 160 bpm

– Fetal bradycardia ≤ 10 min ↓110 bpm

– Acceleration• Increase in the FHR of at least 15 bpm fpr at least 15

seconds.

• Normal findings in second half of pregnancy.

•

Occur as a result of increased sympathetic anddecrease parasympathetic stimulation with fetalmovement.



– Deceleration

• Usually accur intrapartum and related to the uterine

contractions ( periodic decelerations).• Classification:

– Early

» Simultaneous with the contraction.

» Uniform, gradual drops in the FHR that mirror the uterinecontraction and reflect an increased vagal tone from a

transient increase in intracraneal pressure.



– Late

» Starting when the contraction is in progress and

recovering after the contraction is over.

» Poor uterine perfusion or decrease O2

• Causes: Hypotension; IVC compression, blood loss or

regional anesthesia.

– Variable

» Variable in relation to the contraction.» Result from umbilical cord compression by uterine

contraction.

– Isolated variable

» Inadequate recovery between contractions.

» Intervention may be indicate.





• Appendicitis affect 250,000 patient every year

in the US.

• Is the most common nonobstetric indication

for operation during pregnancy

– Average incidence if 1 in 1,500 deliveries.

• Variation in signs and symtoms of appendicitis

during pregnancy (see table).



• Appendiceal lumen obstruction – Lymphoid hyperplasia

– Feacaliths

– Parasites

– Foreign bodies

– Crohn disease

– Metastatic cancer

– Carcinoid syndrome

• Appendiceal lumen obstruction leads to anincrease in intraluminal pressure by blocking thenormal egress of mocus. – Progressive obstruction of venous outflow followed by

capillary and arterial thrombosis leads to mucosalulceration, trasmural wall necrosis and perforation.



First trimester Second Third trimester



trimester

SIGNS AND

SYMPTOMS

% % %

R+ LQ pain 100 50 14

R+ UQ pain 0 17 57

Guarding(muscle spasm)

80 50 43

Nausea and

vomiting

53 60 23

Tenderness on

rectal

examination

60 17 0

Perforation rate 20 49 70



• PE: – Tenderness RLQ

–

Rebound & Guarding (peritoneal signs) – Rovsing sign

• palpation of the LLQ results in more pain in the RLQ

– Dumphy’s sign• increased abdominal pain with coughing

– Psoas sign (retroperitoneal retroccal appendix)• passively extending the thigh of a patient lying on their

side with knees extend

– Obturator sign (Pelvic appendix)•

pain when there is flexion and internal rotation of thehip

– Rectal examination tenderness (Cul-de-sac)

– Low grade fever



• Laboratory – WBC

• 2nd &3rd Trimester: 6,000-16,000

• Absolute number: not reliable

• Differential: levels of band cells can be reliable

indication of infection.

– U/A• mild pyuria or mild hematuria: 20%

• {extraluminal irritation of the ureter, not UTI}.

• mild proteinuria





• A delay in diagnosis occurred in 18% of

patients in the second trimester.

– In third trimester a delay was the rule.

• Delay in operation with a high rate of

perforation.

– 49% in the second trimester

– 70% in the thrid



• Perforated appendicitis presents a greater infectiousrisk. – Large uterus interferes with proper omental migration

throughout the abdominal cavity and prevents the wallingoff the inflammatory process.

– Increase vacularity of abdomen

– Greater lymphatic drainage allows rapid dissemination ofinfection.

• Perforated appendicitis in pregnancy rapidly leads to

diffuse peritonitis, premature labor and fetal loss. – Rate of preterm labor and fetal loss 26 % to 66 %

compared with 0% to 5 % for uncomplicated appendicitis.



• Imaging modalities

– Negative appendectomy rate:

-Clinical diagnosis alone: 54%

-Clinical, US & CT: 8%

1st Line:

US

2nd line:

CT (sensitivity 98%; specificity 98%)

MRI (sensitivity 100%)



33-year-old woman in 13th week of pregnancy with 2 days of right lower quadrantain and clinical sus icion of a endicitis





26-year-old woman in 11th week of pregnancy with right lower quadrant

pain and clinical suspicion of appendicitis

R d



• Reduceinsufflationspressures of 8 to

12 mm Hg. – Decrease fetal

morbidity andmortality.

•

Use open Hassontechnique oftrocar placementunder directvisualizationrather than blindinsufflations witha Veress needle.



• Advantages – Useful in diagnosis

–

Less post-op complication – Earlier mobilization & recovery: fewer thromboembolic

complications

– Lower postoperative narcotic use: less fetal depression

– Shorter hospital stay

• Disadvantages – Experience limited

– Co2 pneumoperitoneum:

– uterine blood flow

– Fetal acidosis – Premature labor

Guidelines for laparoscopic surgery during pregnancy



1. Defer operative intervention until the second trimester, when the fetal risk is

lower, whenever possible.

2. Pneumatic compression devices must be used because of he enhancement of

lower venous stasis with pneumoperitoneum and pregnancy induced

hypercoagulable state.

3. Fetal and uterine status, as well as maternal end-tidal CO2 and arterial blood

gases, should be monitored.

4. Use fluroscopy selectively and protect th uterus with lead shield ifintraoperative cholangiography is possible.

5. Given enlarged gravid uterus, abdominal access should be obtained using open

technique.

6. Dependent positioning should be used to shift the uterus off the inferior venacava.

Pneumoperitoneum pressures should be minimized and not allowed to exceed 15

mm Hg.

7. Obstetric consultation should be obtained before operation.



• Acute cholecystitis in the second most

common general surgery diagnosis during

pregnancy.

• Progesterone induced relaxation of thegallbladder combined with estrogen induced

supersaturation of bile predispose to gallstone

formation.



• The risk for development of gallstones is

related to the number of pregnancies,

doubling after two pregnancies and nearly

quadrupling after four.• Incidence of acute cholecystitis during

pregnancy is relatively low 1 to 8 in 10,000

pregnancies (0.01% to 0.08%).



• Symptoms of cystic duct obstruction:

– Crampy RUQ or epigastric pain after a meal can

last several minutes to hours.

• May radiate to the back• Nausea

• Vomiting

– Tenderness on palpation of the RUQ=acute

cholecystitis



• Labs – Normal leukocytosis

– Elevated alkaline phophatase during pregnancy.

–

Increase bilirubin• Visible jauncide

• Diff. DX

– Hepatitis

– Acute fatty liver of pregnancy

– appendicitis



• Dx

– History

– PE

– Ultrasonography 97% accurate

• Gallbladder wall thickening

• Pericholecystic fluid

•

Pain on palpation with the ultrasound transducer• Sonographic Murphy sign (is confirmatory of

inflamation)



• Management – Maintained on IV hydratation

– Treated with antibiotic for signs of infection.

– A low fat diet

– The surgery was reserved for those with persistentsymptoms, severe toxicity, sepsis, peritonitis orobstructive jaundice.

•

Complication of gallstones – Choledocholithiasis

– pancreatitis



• Laparoscopic cholecystectomy

– Is a safe and reliable modality

– Removing the diseased gallbladder eliminates the

potential for recurence – The minimal uterine retraction need with

laparoscopic.

–

Access to the RUQ should decrease the risk forpreterm labor.



– The incidence of premature uterine contraction withlaparoscopic cholecystectomy has been reported at 0% to21%.

• Usually well controled with tocolytics.

• Spontaneous abortion ranging from 0% to 7%.

• Open cholecystectomy – Rate of premature labor ranges from 0% to 40%.

– Spontaneous abortion or premature birth rate of up to22%.

– Second trimester is the optimal time.• Organogenesis is complete

• Gravid uterus is not yet large enough to impinge on the operatingfield.



• Choledocholithiasis – A bilirubin above 1.5 mg/dL, a dilatad common bile

duct or gallstone pancreatitis.

– Endoscopic retrograde cholangiopancreatograpy

(ERCP) can be performed safely in pregnancy.• Scatter radiation on the order of 4 mrads during whole

examination.

• Evaluation of the biliary tree, stone retrieval, andsphincteroctomy can be performed.

–

Other methods avoid radiation:• Endoscopic ultrasonogaphy

• Endoscopic papillotomy under ultrasonographic control

• Magnetic resonance cholangiography



• 1 in every 68,000 deliveries.

• Adhesions remain the most common cause of

intestinal obstruction in gravid patient.

• Volvulus is much more common complication.



Cause of intestinal obstruction complication

pregnancy and the puerperium in 66 patients.

# and %

Adhesions 39 (59%)

Volvulus 15 (23%)

Sigmoid 7

Cecal 3

midgut 3

Volvulus around vitellointestinal band 2

Intussusception 3 (5%)

Hernia 2 (3%)

Carcinoma 1 (1%)

Appendicitis 1 (1%)

Idiopathic 5 (8%)



• Obstruction during pregnancy classically presentsduring three peak periods. – The first peak

• The 4 a 5 months of gestation as the uterus becomes anintra abdominal organ stretching any previously formedadhesions.

– The second peak• during the 8 a 9 months, when the fetal head descends into

the pelvis, decreases the uterine size.

–

The third peak• After delivery as the sudden decrease in uterine size

drastically change the association of adhesions tosurrounding bowel.



• Presentation and Dx – Abdominal pain and vomiting

– Proximal small bowel obstruction• Results in short period between vomiting episodes with poorly

localized, crampy upper abdominal pain.

– Colonic obstruction• Present with less frequent feculent vomiting and lower abdominal

pain.

– Tachycardia and hypotension are also late signs suggestingbowel compromise and shock.

– Labs• Significant leukocytosis can occur with necrosis and bowel

strangulation.



• Rx

– Serial films every 4 to 6 hrs usually show

progressive changes confirming the dx.





R f



Reference• Nature Reviews Molecular Cell Biology 4. Review: MRI: volumetric imaging for vital imaging and atlas

construction.http://www.nature.com/focus/cellbioimaging/content/images/nrm1195_f1.html .SS10

–SS16. 2003.

• American Academy of Family Physicians. Clinical Interpretations of Fetal Monitor Patterns and theDetailed Implications Regarding Fetal Health: May 1, 1999.

• Appendicitis in Pregnancy: Methods. http://www.medscape.com/viewarticle/549510_4

• Acute appendicit is: Pregnancy complicates this diagnosis

• http://www.jaapa.com/acute-appendicitis-pregnancy-complicates-this-diagnosis/article/130146/

• Lodewijk P. Cobben. MRI for Clinically Suspected Appendicitis During Pregnancy. September 2004 vol.

183 no. 3 671-675 http://www.ajronline.org/content/183/3/671.full

• Stavros Zarkadas. LAPAROSCOPIC APPROACH IN ACUTE ABDOMINAL PROCESSES DURINGPREGNANCY.http://www.laparoscopyhospital.com/laparoscopy_for_acute_abdomen_in_pregnancy.html

•

http://www.nature.com/focus/cellbioimaging/content/images/nrm1195_f1.html%20.SS10%E2%80%93SS16.%202003









http://www.medscape.com/viewarticle/549510_4

http://www.jaapa.com/acute-appendicitis-pregnancy-complicates-this-diagnosis/article/130146/

http://www.ajronline.org/content/183/3/671.full















http://www.medscape.com/viewarticle/549510_4




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