Practice Guidelines for Obstetric Anaesthesia : Dr Vandana Talwar

        
 

Practice Guidelines for Obstetric Anaesthesia

Dr Vandana Talwar, Senior Specialist, Department of Anaesthesia and intensive Care

VMMC and Safdarjung Hospital

An updated Report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia. Anesthesiology, V 106, No 4, April 2007.

American Society of Anesthesiologists Task Force on Obstetric Anesthesia has laid down the following recommendations, focusing on the anaesthetic management of pregnant patients during labor, non operative and operative delivery and postpartum care and analgesia.

I Peri anaesthetic Evaluation

1. History and Physical Examination.
   
2. Intrapartum platelet count: In suspected pre eclampsia and coagulopathy.
   
3. Blood Type and Screen.
   
4. Peri anaesthetic recording of the fetal heat rate prior to and after administration of
   

   central neuraxial block (CNB) for labor.
   

II Aspiration Pneumonia

1. Clear liquids: Allowed in elective LSCS upto 2 h before induction and in uncomplicated labor.
   
2. Solids: Withheld during labor and 6-8 h before surgery (LSCS / Tubal ligation).
   
3. Antacids, H₂ blockers and Metoclopramide: Timely administration.
   

III Anaesthetic Care for Labor and Vaginal Delivery

1. Overview: Neuraxial analgesia should be offered in early labor (< 5cm dilatation) with a primary goal of adequate maternal analgesia with minimal motor block. Intravenous (IV) infusion should be established before the block.
   
2. Continuous Infusion Epidural Analgesia (CIEA)
   

   Addition of an opioid to a continuous epidural infusion of local anaesthetic (LA) reduces the concentration of LA, improves the quality of analgesia and minimizes motor block.
   

3. Single injection Spinal Opioids with or without LA
   

Rapid onset of analgesia may be advantageous for selected patients (e.g. those in

advanced labor). Addition of a LA increases duration and improves quality of

analgesia. Catheter technique is considered if long duration of labor or an operative

delivery is expected.

4. Combined Spinal-Epidural Analgesia (CSEA)

CSE with LA and opioids provide effective and rapid onset analgesia compared with

epidural LA with opioids.

5. Patient-Controlled Epidural Analgesia (PCEA)

PCEA (with or without a background infusion) improves analgesia, reduces the dose of LA and need for anaesthetic interventions as compared to CIEA.

IV Removal of Retained Placenta

1. Anesthetic Techniques
   

Epidural anaesthesia is preferred if the patient is haemodynamically stable and has a

catheter in place. In presence of excessive bleeding, GA with an endotracheal tube is

preferable to neuraxial anaesthesia. Aspiration prophylaxis should be considered.

1. Uterine Relaxation
   

Incremental doses of IV or sublingual (metered dose spray) nitroglycerine is an

alternative to terbutaline sulphate or GA with halogenated anaesthetics as it relaxes

the uterus and minimizes hypotension.

V. Anaesthetic Choices for Caesarean Delivery

1. GA, Epidural, Spinal or CSE
   
   1. Anaesthetic technique should be individualized.
      
   2. Neuraxial techniques are preferred to GA
      
   3. Induction-delivery interval is shorter for spinal anaesthesia as compared to epidural, but for urgent caesarean delivery, onset of anaesthesia is similar between indwelling epidural catheter and spinal anaesthesia.
      
   4. Spinal anaesthesia: Pencil point needles are preferred to cutting-bevel spinal needles to reduce risk of post-dural puncture headache.
      
   5. GA: Reduces time to skin incision as compared to CNB but increases fetal and neonatal complications. It may be preferred in profound fetal bradycardia, ruptured uterus, severe hemorrhage and severe placental abruption.
      
   6. Uterine displacement (usually left lateral) should be maintained till delivery irrespective of anaesthetic technique.
      
2. IV Fluid Loading
   

Preloading reduces incidence of maternal hypotension, but spinal anaesthesia should

not be delayed to administer a fixed volume of IV fluid.

1. Ephedrine or Phenyleprine
   

IV ephedrine and phenylephrine are used for treating hypotension due to CNB. In

uncomplicated pregnancies and absence of maternal bradycardia, phenylephrine

may be preferable because of improved fetal acid-base status.

VI Postpartum Tubal Ligation

CNB is preferred to GA. Aspiration prophylaxis should be considered as gastric

emptying is delayed in patients who receive opioids during labor.

VII Management of Obstetric and Anaesthetic Emergencies

1. Use of type-specific 0 negative blood is acceptable in an emergency. Intra operative cell salvalge should be considered in cases with intractable hemorrhage when banked blood is not available.
   

2. Equipment for Management of Airway Emergencies

Personnel and equipment to manage airway emergencies must be available in labor rooms, during provision of neuraxial analgesia and in operating rooms. Anaesthesiologist should have a strategy for intubation of the difficult airway.

3. CPR

    Basic and advanced life-support equipment should be available. Left lateral

position should be maintained and the baby delivered by caesarian section if

circulation is not restored within 4 min.

Corresponding Author: Dr. Vandana Talwar

E Mail: vandtal@yahoo.com