Abdominal mass Abdominal mass in a pregnancyin a pregnancy --Case presentationCase presentation

By R3By R3陳世昱陳世昱

General & Past HistoryGeneral & Past History

35 y/o female35 y/o female Denied past history of systemic disease Denied past history of systemic disease

or opor op No contributable family/drug/allergy hNo contributable family/drug/allergy h

istoryistory H: 160cm, W: 54kgH: 160cm, W: 54kg PregnancyPregnancy ( (6wks6wks ; ; LMP:2003/3/17LMP:2003/3/17) with p) with p

rogressive abdominal distentionrogressive abdominal distention

Present Illness Present Illness (summary 1)(summary 1)

RLQ pain 9 yrs agoRLQ pain 9 yrs ago 1998/10, TAS:7x6cm right pelvic mass, sus1998/10, TAS:7x6cm right pelvic mass, sus

pect endometriosis pect endometriosis (which regressed 3 months later spo(which regressed 3 months later spontaneously)ntaneously)

1999/8, TAS:12x8x8cm heterogeneous mas1999/8, TAS:12x8x8cm heterogeneous mass over uterine fundus and ~30ml ascites; Ms over uterine fundus and ~30ml ascites; MRI revealed a 1.5cm ROV cyst, and CA-125:RI revealed a 1.5cm ROV cyst, and CA-125:WNLWNL

No GI or URO S/S nor ↑CA-125, so OPD f/u No GI or URO S/S nor ↑CA-125, so OPD f/u was suggested and kept.was suggested and kept.

Present Illness Present Illness (summary 2)(summary 2)

Missed MC period in 2003/4, and urine pregMissed MC period in 2003/4, and urine pregnancy test showed positive resultnancy test showed positive result

Progressive abdominal distension soon laterProgressive abdominal distension soon later 4/23 OPD :4/23 OPD :

TAS: >25x20cm pelvic mass c lacunar pattern anTAS: >25x20cm pelvic mass c lacunar pattern and solid component and moderate ascitesd solid component and moderate ascites

↑↑CA-125: 578CA-125: 578μμ/ml/ml R/O ovarian malignancy → surgical evaluatiR/O ovarian malignancy → surgical evaluati

onon

麻醉紀錄麻醉紀錄

Non-obstetric Non-obstetric Surgery during Surgery during

PregnancyPregnancy

DiscussioDiscussionn : :

IncidenceIncidence

About 0.3~2% of deliveriesAbout 0.3~2% of deliveries Most common: appendectomyMost common: appendectomy Almost every type of surgical Almost every type of surgical

procedureprocedure

Basic objectivesBasic objectives

Maternal safetyMaternal safety Avoidance of teratogenic drugsAvoidance of teratogenic drugs Avoidance of intrauterine fetal Avoidance of intrauterine fetal

asphyxiaasphyxia Prevention of preterm laborPrevention of preterm labor

MonitoringMonitoring

Routine monitorsRoutine monitors Fetal heart rate monitoring: Doppler apparaFetal heart rate monitoring: Doppler appara

tus such as tocodynamometer(≥umbilicus) tus such as tocodynamometer(≥umbilicus) after 16wks of pregnancy.after 16wks of pregnancy.

An obstetrician is present throughout operaAn obstetrician is present throughout operationtion

Elevations of maternal BP may treat fetal brElevations of maternal BP may treat fetal bradycardia, and inhalation agents may diminadycardia, and inhalation agents may diminish the amplitude of uterine contractions.ish the amplitude of uterine contractions.

Physiologic ChangesPhysiologic Changes

Teratogenic drugs(1)Teratogenic drugs(1)

Teratogen: a substance produces an increTeratogen: a substance produces an increase in incidence of a particular defect that ase in incidence of a particular defect that can’t be attributed to chance. A sufficiencan’t be attributed to chance. A sufficient dose at a critical point in development is t dose at a critical point in development is needed.needed.

Critical point in human: during organogeCritical point in human: during organogenesis, which extends from 15 days’ to apnesis, which extends from 15 days’ to approximately 60 days’ gestational age.proximately 60 days’ gestational age. CNS does not fully develop until after birth, sCNS does not fully develop until after birth, s

o critical time for this system could be througo critical time for this system could be through the entire gestation.h the entire gestation.

Teratogenic drugs(2)Teratogenic drugs(2)

Almost every anesthetic or drug has been founAlmost every anesthetic or drug has been found to be a teratogen in an animal model (in greatd to be a teratogen in an animal model (in greatly exceeded doses than used clinically), but no ly exceeded doses than used clinically), but no anesthetic drug has been documented to be a teanesthetic drug has been documented to be a teratogen in humans.ratogen in humans.

BZDBZD, , BarbituratesBarbiturates, , KetamineKetamine, , PropofolPropofol and and EtoEtomidatemidate are known teratogens in animals, but h are known teratogens in animals, but have never been demonstrated in humans.ave never been demonstrated in humans.

NarcoticsNarcotics: CNS abnormalities in hamster, but n: CNS abnormalities in hamster, but never been reproduced in humans. Low-birth-wever been reproduced in humans. Low-birth-weight babies has been associated with chronic aeight babies has been associated with chronic administration, but no congenital defects.dministration, but no congenital defects.

Teratogenic drugs(3)Teratogenic drugs(3)

Muscle relaxantsMuscle relaxants: cause skeletal abnormalities : cause skeletal abnormalities in the chick embryo, but never been reproducein the chick embryo, but never been reproduced in the human fetus; do NOT cross the placentd in the human fetus; do NOT cross the placentaa

Nitrous oxideNitrous oxide: ↓Vit.B12→↓methionine synthe: ↓Vit.B12→↓methionine synthetase→↓DNA synthesis, but has been used in htase→↓DNA synthesis, but has been used in hundreds of anesthetics s problems.undreds of anesthetics s problems.

Halogenated agentsHalogenated agents: beneficial to fetus by : beneficial to fetus by ututerine relaxationerine relaxation and and increasing uterine blooincreasing uterine blood flowd flow, and so far found it safe in clinical doses., and so far found it safe in clinical doses.

Avoidance of intrauterine fetal Avoidance of intrauterine fetal asphyxiaasphyxia Maintain maternal PaO2:Maintain maternal PaO2:

Relative difficult airwayRelative difficult airway ↓↓FRC→↑rate of desaturationFRC→↑rate of desaturation Prevent Prevent high levelhigh leveltoxic local anesthetics toxicity toxic local anesthetics toxicity

andandoversedation in regional anesthesiaoversedation in regional anesthesia Adequate maternal PaCO2:Adequate maternal PaCO2:

Hypocapnia:Hypocapnia: By excessive positive ventilation→↑intrathoracic pressureBy excessive positive ventilation→↑intrathoracic pressure

→↓venous return→↓uterine blood flow→↓venous return→↓uterine blood flow Maternal alkalosis→vasoconstriction & left shift of O2-Hb dMaternal alkalosis→vasoconstriction & left shift of O2-Hb d

is. curveis. curve Hypercapnia: fetal acidosisHypercapnia: fetal acidosis

Maintain uterine blood flow:Maintain uterine blood flow: Perfusion pressure: prevent hypotension, aortocaval Perfusion pressure: prevent hypotension, aortocaval

compression, hemorrhage and “heavy” regional acompression, hemorrhage and “heavy” regional anesthesianesthesia

Vasoconstriction: prevent Vasoconstriction: prevent αα -agonist, ↓PaCO2 & ↑ca-agonist, ↓PaCO2 & ↑catecholamines (pain, insufficient anesthesia or so)techolamines (pain, insufficient anesthesia or so)

Prevent of Preterm LaborPrevent of Preterm Labor

The only factors correlated with preterm labor aThe only factors correlated with preterm labor are the re the typetype and and locationlocation of the procedure. of the procedure.

No study documents any correlation of anesthetiNo study documents any correlation of anesthetic drug or technique with preterm laborc drug or technique with preterm labor

However, in theoretically, some anesthetic agenHowever, in theoretically, some anesthetic agents such as ts such as ketamineketamine(>1mg/kg) and (>1mg/kg) and phenylephrinphenylephrinee that can increase uterine tone should be avoid that can increase uterine tone should be avoid as possible.as possible.

The The halogenated agentshalogenated agents ↓uterine tone &↑uteri ↓uterine tone &↑uterine blood flow and may be beneficial in this aspene blood flow and may be beneficial in this aspect.ct.

Recommendations of Recommendations of anesthetizing a pregnancy anesthetizing a pregnancy for Non-obstetric Surgeryfor Non-obstetric Surgery Avoid surgery and anesthesia in the first Avoid surgery and anesthesia in the first trimester, if possible, without compromising trimester, if possible, without compromising maternal health.maternal health.

Non-particulate antacid for aspiration Non-particulate antacid for aspiration pneumonitis prophylaxis after first trimesterpneumonitis prophylaxis after first trimester

Transport patient with left uterine Transport patient with left uterine displacementdisplacement

Continuing fetal/uterus monitoring if possibleContinuing fetal/uterus monitoring if possible Regional anesthesia is recommended Regional anesthesia is recommended

whenever possible whenever possible (fluid preloading; fluid and/or (fluid preloading; fluid and/or ephedrine)ephedrine)

Recommendations of Recommendations of anesthetizing a pregnancy anesthetizing a pregnancy for Non-obstetric Surgeryfor Non-obstetric Surgery General anesthesia:General anesthesia: Avoid hypotension with fluid preloadingAvoid hypotension with fluid preloading Airway managements:Airway managements:

Pre-oxygenation with 100%O2Pre-oxygenation with 100%O2 Induction : rapid-sequence with cricoid-pressureInduction : rapid-sequence with cricoid-pressure Maintain adequate oxygenation(50% or higher) and norMaintain adequate oxygenation(50% or higher) and nor

mocarbiamocarbia Anesthetic agents:Anesthetic agents:

Drug of Choice: with a long history and relative safetyDrug of Choice: with a long history and relative safety Pentothal, morphine, fentanyl, meperidine,nitro-oxidePentothal, morphine, fentanyl, meperidine,nitro-oxide SCC,Atracurium, vecuronium, curare and pancuroniumSCC,Atracurium, vecuronium, curare and pancuronium Halogenated agents Halogenated agents may be beneficialmay be beneficial KetamineKetamine and and αα-agonist-agonist should be avoid should be avoid

Antagonize muscle relaxant and extubate when fAntagonize muscle relaxant and extubate when fully awake and able to control airway reflexsully awake and able to control airway reflexs