Anaesthetic management of obstetric emergencies

1. ANAESTHETIC
MANAGEMENT OF
OBSTETRIC
EMERGENCIES
BY : DR HIMANSHU SHARMA
ANAESTHESIA DEPARTMENT
MLB MEDICAL COLLEGE

2. • Obstetrical emergencies are life-threatening medical conditions that
occur in pregnancy or during or after labor and delivery

4. CLASSIFICATION
1) Antepartum Haemorrhage : Per vagina blood loss after 20 weeks’
gestation
a) placenta previa
b) placental abruption
c) uterine rupture
2) Post partum Haemorrhage
a) uterine atony
b) Retained placenta
c) Placenta accreta
d) birth trauma or laceration
e) coagulopathy

5. PLACENTA PREVIA
Defined as a placenta implanted in the lower segment of the uterus,
presenting ahead of the leading pole of the fetus.
1. Total placenta previa: The internal cervical os is covered completely
by placenta.
2. Partial placenta previa: The internal os is partially covered by
placenta.
3. Marginal placenta previa: The edge of the placenta is at the margin
of the internal os.
4. Low-lying placenta :The placenta is implanted in the lower uterine
segment , close proximity to internal os

6. Risk factors
• Advancing maternal age
• Multiparity
• Multifetal gestations
• Prior cesarean delivery
• Smoking
• Prior placenta previa

7. • The most characteristic feature in placenta
previa is painless hemorrhage.
• This usually occurs near the end of or after the
second trimester.
• The initial bleeding is rarely so profuse as to
prove fatal.
• Placenta previa may be associated with
placenta accreta, placenta increta or percreta.
• Coagulopathy is rare with placenta previa

8. • Placenta previa or abruption should always be suspected in women
with uterine bleeding during the latter half of pregnancy.
• Double Setup Examination
-The diagnosis of placenta previa can seldom be established firmly by
clinical examination. Such examination of the cervix is never
permissible unless the woman is in an operating room with all the
preparations for immediate cesarean delivery, because even the
gentlest examination of this sort can cause torrential hemorrhage.

9. • The simplest and safest method of placental localization is provided
by transabdominal sonography
• Transvaginal ultrasonography – Gold Standard
• MRI
• At 18 weeks, 5-10% of placentas are low lying. Most ‘migrate’ with
development of the lower uterine segment

12. PLACENTA PREVIA :ANAESTHETIC
MANAGEMENT
• Ask Obstetrician about previous cesarean scar on ultrasound [risk of
accreta]
• Place two large bore IV lines and have warmers available.
• Invasive monitoring
• Ensure -- blood typed and cross matched.
• Volume resuscitation should be initiated using a non–dextrose-containing
balanced salt solution (e.g., lactated Ringer’s, normal saline)
• Placing a peripherally-inserted central catheter (PICC) for drug
administration so that other peripheral veins are preserved for large-bore
intravenous catheter access in the event of hemorrhagic emergency
• Examine the airway in case emergency G/A is required and provide
aspiration prophylaxis

13. What type of anaesthetic?
• Neuraxial anesthesia is preferred in patients with placenta previa without
active bleeding or intravascular volume deficit.
• Rapid-sequence induction of general anesthesia is the preferred technique
for bleeding patients
• The choice of intravenous induction agent depends on the degree of
cardiovascular instability
• Ketamine and etomidate are useful alternative induction agents for
hemodynamically unstable patients
• Ketamine 0.5 to 1.0 mg/kg has an excellent record of safety & efficacy
• Etomidate 0.3 mg/kg causes minimal cardiac depression
• Disadvantages of etomidate include venous irritation, myoclonus, and
possible adrenal suppression.

14. • In case of massive bleed, it may be best to discontinue the volatile
halogenated agent after delivery and to substitute 70% nitrous oxide
and an intravenous opioid or ketamine.

15. PLACENTAL ABRUPTION
• Defined as the premature separation of the normally implanted
placenta.
• Types:
external hemorrhage
concealed hemorrhage
Total
Partial

17. DIAGNOSIS OF ABRUPTION
• Vaginal bleeding with abdominal pain
• Uterine hypertonicity
• Fetal distress
• Nonreassuring fetal heart rate (FHR)
• Retroplacental clot
• Ultrasonography is highly specific for placental abruption , but it is not
very sensitive

18. MANAGEMENT OF ABRUPTION
• Evaluate maternal stability[vital signs,coagulation studies,hematocrit]
• Evaluate fetal well-being and maturity
• In cases of severe hemorrhage, insertion of an intra-arterial catheter
may aid prompt recognition of hypotension and allow for frequent
blood sampling and assessment of anemia and coagulation status
• If severe fetal distress and/or maternal instability: urgent C/S
• If stable mother and fetus: induction of labor and vaginal delivery

19. ANAESTHETIC MANAGEMENT
• Ensure good IV access and availability.
• Labor and Vaginal Delivery.
Neuraxial labor analgesia may be offered in the setting of abruption
provided that hypovolemia has been treated and coagulation status is
normal.
Close monitoring needs to be done
• Cesarean Delivery.
Spinal, combined-spinal epidural, or epidural anesthesia may be
administered in stable patients in whom intravascular volume status is
adequate and coagulation studies are normal.

20. • General anesthesia is preferred for most cases of urgent cesarean
delivery accompanied by unstable maternal status, a nonreassuring
FHR pattern.
• Ketamine and etomidate are preferred.
• Aggressive volume resuscitation is critical (crystalloid or colloid).
• Persistent uterine atony requires the administration of other
uterotonic drugs

21. UTERINE RUPTURE

22. DIAGNOSIS OF UTERINE RUPTURE
• Abdominal pain (most common)
• Fetal distress (abnormal FHR – 1st sign)
• vaginal bleeding
• uterine hypertonia
• cessation of labor
• loss of the fetal station
• decrease in cervical dilation
• Breakthrough pain during neuraxial labor analgesia may also indicate
uterine rupture.

23. MANAGEMENT OF UTERINE RUPTURE
• Uterine repair
• Hysterectomy
ANAESTHETIC MANAGEMENT
• Patient evaluation and resuscitation initiated
• General anesthesia is necessary, except in some stable patients with
preexisting epidural labor analgesia
• Aggressive volume replacement & Blood Transfusion
• Urine output should be monitored
• Invasive hemodynamic monitoring

24. Vasa Previa
• Velamentous insertion of the fetal vessels over the cervical os (i.e.,
the fetal vessels traverse the fetal membranes ahead of the fetal
presenting part)
• The fetal vessels are not protected by the placenta or the umbilical
cord

25. Diagnosis
• Bleeding occurs with rupture of membranes
• Examination of the shed blood for evidence of fetal hemoglobin (e.g.,
Kleihauer-Betke test)
• Ultrasonography
• Transvaginal color Doppler

26. Anesthetic Management
• Ruptured vasa previa is a true obstetric emergency that requires
immediate delivery of the fetus, almost always by the abdominal
route
• The choice of anesthetic technique depends on the urgency of the
cesarean delivery.
• General anesthesia is necessary for prompt delivery.

27. POST PARTUM HAEMORRHAGE
Definition of PPH:
• Blood loss greater than 500 ml for vaginal and 1000 ml for cesarean
delivery.
OR
• PPH is a 10% drop in haematocrit from admission to the postpartum
period or the need to administer PRBCs owing to postpartum blood
loss

30. MANAGEMENT OF PPH
1. Move to OT
2. Bimanual uterine compression and massage
3. Infusion of oxytocin
4. Evaluation for retained placenta
5. Use of other oxytocics
6. resuscitation
7. large bore IV cannula,monitors,warmer
8. Analgesia pre existing epidural, ketamine ,G/A

31. Uterine Atony

32. Retained Placenta
Retained placenta is defined as failure to deliver the placenta
completely within 30 minutes after delivery of the infant
Anesthetic Management
• In some cases, the administration of small amounts of sedatives and
analgesics are enough
• In some cases, the obstetrician requires uterine relaxation to facilitate
manual removal of placenta
• Rapid sequence induction , followed by the administration of a high
dose of volatile halogenated agent to relax the uterus.

33. • Uterine contractility is decreased by 50% with administration of
approximately 1.5 minimum alveolar concentration (MAC) of a
volatile anesthetic agent.
• Nitroglycerin may be administered for uterine relaxation @ dose 50
to 100 µg IV or sublingually via spray or tablet

34. Placenta Accreta
• Placenta accreta is defined as a placenta that in whole or in part
invades the uterine wall and is inseparable from it.
• Placenta accreta vera is defined as adherence of the basal plate of the
placenta directly to uterine myometrium without an intervening
decidual layer.
• Placenta increta refers to a placenta in which chorionic villi invade the
myometrium.
• Placenta percreta represents invasion through the myometrium into
serosa and sometimes into adjacent organs, most often the bladder.

35. Anesthetic Management
• Anesthesia for peripartum hysterectomy is frequently challenging
because massive blood loss may occur unpredictably.
• As the magnitude of blood loss increases, general anesthesia
becomes the anesthetic technique of choice.
• Severely hypotensive patients may require tracheal intubation for
airway protection
• Large fluid shifts and massive transfusion may adversely affect
oxygenation so that control of ventilation via an endotracheal tube
becomes necessary

36. • These same fluid shifts increase airway edema, potentially making
failed ventilation/failed tracheal intubation more likely as the surgery
proceeds.
• The massive transfusion of blood products & vasopressors require
central venous access
• At least 4 units of PRBCs should be immediately available, with
additional blood products, including plasma and cryoprecipitate.
• Vasoactive drugs (e.g., phenylephrine, epinephrine) should be
available.

37. MEOWS : Modified early obstetric warning
system --- useful tool to predict morbidity

38. COAGULOPATHY IN OBSTETRICS
• Dilutional , consumption, DIC and fibrinolysis
• Causes : Abruptio, Pre-eclampsia, Bleeding disorders
• Fibrinogen levels < 2 gm/l (severe PPH)
• ROTEM & TEG : viscoelastic methods are useful (Whole blood
coagulation, clot strength, stability and lysis )

39. TRANSFUSION OF BLOOD AND BLOOD
PRODUCTS
Hb
Platelet
Prothrombintime
Activated PT
Fibrinogen
≥8 gm
/dl
≥75 X 109/L
≤1.5 meancontrol
≤1.5 mean control
≥1 gm
/dl
AIM to maintain :

40. TRANSFUSION PROTOCOL
Shock packs –
• Red cells: FFP: Platelets = 1 : 1 :1
• Adv : decreases mortality and MOF
• Disadv : TRALI, circulatory overload Cryoprecipitate –
✓Fibrinogen is 10 times more than in FFP
✓To raise fibrinogen levels by 1 gm/L needs
30 ml/Kg FFP
3 ml/ Kg cryoprecipitate
Fibrinogen concentrate –
✓Powder at room temp
✓No need to thaw or blood typing

41. • Intra op cell salvage technique as adjunct (only RBCs)
• Recombinant Activated Factor VII
-Controversy in use
-May result in thrombotic complications
-dose: 90 mcg/Kg IV over 3-5 min.
- (temp. > 34˚C , ph > 7.2, platelets> 50 k
- fibrinogen > 1 gm
• Tranexemic acid :
Shown to dec bleeding & transfusion requirement
• Most beneficial --- in increased fibrinolysis

45. Few considerations
• Prophylaxis against acid aspiration:
• proton-pump inhibitors: pantoprazole 40 mg I/V prokinetic agents:
metoclopramide 10 mg
• Patient position to prevent neonatal depression, induction of
anaesthesia is usually carried out after the patient is catheterized.
• Left lateral tilt : to avoid aorto-caval compression.
• 30° head-up tilt : useful in improving maternal well-being through an
increased FRC and reduced gastro-oesophageal reflux. Reduced
breast interference to intubation

46. Preoxygenation
• As FRC is reduced by 40% at term gestation and oxygen consumption is increased
by 20%, oxygen reserves get rapidly depleted.
• pre-oxygenation with 100% oxygen using a tight-fitting face mask by tidal volume
breathing for 3 min Or 4 to 8 vital capacity breaths.
Intravenous induction
• Rapid-sequence technique is preferred for induction of general anaesthesia
Cricoid pressure
• Cricoid pressure of 10 N applied on the cricoid cartilage towards the body of C6
vertebra, directed perpendicular to the tilted table. The pressure is increased to
20 to 40 N after induction and kept in place until tracheal intubation with ETCO2
is confirmed and till the cuff of the tracheal tube is inflated.

47. • When GA is given, tracheal intubation is the choice
• Availability of video laryngoscope to improve chance of success
• Supraglottic devices come as rescue devices second generation
SGADs with gastric channel are to be preferred
• Monitoring of EtCO2 : ASA standards
• Isoflurane/sevoflurane with end tidal monitoring
• Nitrous oxide can be used
• Opiod Analgesic after delivery of baby

48. THANK YOU