Joseph E Pellegrini, PhD, CRNA Associate Professor & Program Director University of Maryland Nurse Anesthesia Program

 High Spinal Anesthesia following a failed epidural for Cesarean Delivery ◦ WHAT DO YOU DO????????  Spinal, Repeat CLE, General Anesthesia  SAB – If chosen then how much needs to be given  Early versus late epidural analgesia ◦ When is it TOO LATE or TOO EARLY  The “old” and “new” arguments regarding timing and adverse events  Is there such a thing as a “window”???  Prophylactic Treatment following a “WET TAP” ◦ Is there anything that can be done??

 In 1991 Kestin (Br J Anaesth 1991; 66:596) reported that spinal anesthesia is safe to use and should always be considered in patients with difficult airway ◦ Flawed thinking?  Mets et al. (Anesth Analg 1993; 77: 629) disputed this and recommended that spinal should never be used in the case of failed epidural ◦ Case report ◦ Flawed thinking? ◦ CSE reported as safe

11% 0.1%

 Number of Top-ups during Labor ◦ Studies showed that the risk of failure increases exponentially with each required top-off  Average rate of failure among those CLEs not requiring top-off 4.6% (range 1.1% - 9.9%)  Average rate of failure among those CLEs that require top-off 16.4% (range 6.8% %)  Highest ratios noted when ≥ 2 boluses required

Bauer et al. 2012

 Urgency of Cesarean Delivery  Often epidural not given sufficient time to set up  Failure rate  25% for Category 1 (Maternal or Fetal Compromise – Life Threatening)  7% for Category 2 (Maternal or fetal compromise – non life threatening)  2.4% for Category 3 (no compromise)  Overall reported that 7.6% CLEs not used secondary to poor quality analgesia noted during labor  SAB often performed

Bauer et al. 2012

Non-obstetric anesthesia provider  Better control and increased overall success rates with dedicated OB providers:  i.e. 7.2% failure rate in Non-OB anesthesia providers versus 1.6% failure rate in OB anesthesia providers  Campbell (2009) reported that 85% of ineffective analgesia/anesthesia can be remedied by withdrawal of catheter 1 cm prior to administering further doses  This is done in 58% of the time by OB anesthesia personnel versus only about 6% by non-OB anesthesia personnel  Typically this is done by experienced OB anesthesia personnel prior to administration of 1 st top off

Bauer et al. 2012

 No Differences found  Duration of Epidural Analgesia  Most often duration 3-4 hours  CSE versus standard CLE  Intrathecal dose of bupivacaine varied  Evidence indicates success with initial placement of CLE when CSE technique used  Body Mass Index or Weight  Cervical Dilation  Some controversy  Still recommend waiting to at least 3 cm

 Choice determined by urgency of C-section  Failed Epidural ◦ Spinal Anesthesia  Difficult to determine adequate dose ◦ General Anesthesia  Viable option but w/problems  Airway concerns  Postoperative analgesia ◦ Combined Spinal-Epidural Anesthesia  Often cited as the best choice  Can give low dose SAB  Supplemental anesthesia/analgesia

Dosing a Spinal following a failed Epidural

Dadarkar P, Int J Ob Anes; 2012

◦ Using a Standardized Dose  Incidence of high or total spinal reported between.2% - 17% in some studies  Data suggest greater possibility to total SAB anesthesia after failed CLE when standard dose used ◦ Using a Reduced Dose  Reduce dose 25-30% as described in multiple studies  i.e. 12 mg standardized dose reduced to mg  Some recommend a further 5% reduction if opioids added to admixture  Reduce or eliminate opioids as an alternative to reducing standardized dose  Use calculation model  Can be used with and without opioids

 Some advocate using a 25-30% reduction rule ◦ Assuming your going to give a 12 mg standardized dose ◦ Often co-administered with opioids  12 mg X 0.3 = 3.6 mg  12 mg X 0.25 = 3 mg  For a 30% reduction the dose to administer is 8.4 mg  For a 25 % reduction the dose to administer is 9 mg  Using a formula: ◦ Noted partial block up to T- 10  6 segments w/no block + 12 segments w/some block  (0.5) = 6+6 X 12mg/18  12 times 12 = 144  144/18 = 8 mg ( (closely resembles the 30% rule) Vanbera et al. Anes 96:1 2002

◦ Replace Epidural Catheter  Inherent problems ◦ Use a dedicated OB anesthesia provider  One of the most influential factors  Need of additional training/experiences  Many facilities use PRN providers ◦ Reduction in Dose recommended by many practitioners  Reduce Dose by 25-30% (30% most common)  Reduce Dose using calculation model  Both have been shown to be efficacious ◦ Use CSE technique  Administer reduced dose of IT LA  Dose CLE PRN and administer opioids at end of procedure ◦ General Anesthesia  One Study reports incidence of high SAB following failed CLE 1:17

 Thorp et al compared IV meperidine & promethazine to CLE ◦ Reported problems  Reported arrest of cervical dilation in stage 2  Increased C-section rate in CLE group (25% vs 2%)  16.7% incidence of dystocia

 Recommendations from study ◦ CLE should be placed after cervical dilation of > 5 cm achieved  Incidence of malpresentation was 4.4% versus 18/8%  Oxytocin augmentation – 26.7% versus 58.3%  CLE was attributed with lower VAS scores for pain and higher overall APGAR scores  Prompted practitioners to re-examine practices

 Conclusions – based on the evidence ◦ Epidural analgesia DOES:  Increase motor blockade  Increase incidence of hypotension  Increase length of stage I and stage II of labor  Provide superior analgesia over IV, IM treatment regimens  Lead to better APGAR scores ◦ Epidural analgesia DOES NOT:  Increase rate of cesarean delivery  Increase rate of dystocia ◦ Epidural analgesia MAY:  Increase rate of instrumental deliveries  Inconclusive evidence- operator bias – training purposes not excluded in many studies  Waiting until at least 4 cm dilation may have some benefit but not significant ◦ Multiple studies show that placement at 2-3 cm not detrimental in terms of C/S and dystocia  Can administer as late at 9 cm in nulliparous women (depending on practice)

Treatment & Prevention Options

 39% of all women report H/A in 1 st week following delivery ◦ Of these only 4.7% attributed to PDPHA  Rate of accidental dural puncture after CLE placement varies from 0.19%-3.6%  50% of these people will experience PDPHA  Treatment regimens  Prophylactic blood patch (10-31%)*  Long-term intrathecal catheter placement (19%)*  Epidural saline bolus (12-25%)*  Alternative approaches  Methylxanthines/ caffeine etc. * Harrington B, Schmitt A. Management of accidental dural puncture, and the epidural blood patch: a national survey of US practice. Reg Anesth Pain Med 2009: 34:

Loss of hearing

 Routinely administered shortly after delivery before CLE removed in patients that have had an inadvertent “wet tap” ◦ CLE placed in different interspace ◦ Usually give ml autologous blood  Can be less with symptomatic pain/pressure on injection  Anecdotal reports of efficacy ◦ Some early studies support prophylaxis  Later studies dispute earlier findings

 Prophylactic blood patch (PEBP) not recommended (overall) ◦ Earlier studies showed efficacy ◦ Later better controlled studies indicated little if any benefit while significantly increasing risk  Consider timing of Blood patch ◦ 71% failure rate reported when PEBP placed w/in 24 hours after puncture ◦ 4% failure rate when applied later than 24 hours Recommend conservative treatment for first 24 hours and EBP if symptoms persist

 Prophylactic Saline ◦ Based on limited evidence no benefit derived on prophylactically administering normal saline bolus or infusion  Some benefit in decreasing time to full motor return

Cosyntropin 1 mg IV over 5 minutes

 Recommendations ◦ Prophylactic Cosyntropin Dose is 1.5 units/kg in 500 ml LR or NS over min ◦ Cosyntropin Treatment  Dose is 1.5 units/kg in 500 ml LR or NS over min  May be answer in coagulation problem patients  Success rates range from 70-95% (equivalent to EBP) ◦ Bedrest, fluids, caffeine continue as mainstay  Methylxanthines also effective Epidural blood patch most effective if given at least 24 hours following dural puncture

 Management of side effects ◦ Nausea & Vomiting ◦ Pruritus  Multiple Treatment modalities ◦ Ondansetron ◦ Naloxone ◦ Other  Diphenhydramine  Promethazine

 Multiple Treatment regimens recommended ◦ Propofol  No definitive studies showed effective when administered prophylactically  Some evidence to indicate efficacy with treatment ◦ Ondansetron  Not effective for prophylaxis or treatment  Some studies do show efficacy with a similar effectiveness to dihphenydramine ◦ Promethazine  Evidence indicates efficacy when administered IM prophylactically  Not recommended for IV use

 Common antiemetic agent used in OB ◦ Possesses strong anticholinergic and antihistamine properties  Two studies noted that when Promethazine administered as antiemetic agent to groups of patients administered epidural/intrathecal morphine noted a significant reduction in PONV and pruritis ◦ Both studies used small sample sizes (<20 patients) ◦ Not used in OB population ◦ Study design not specific to measure pruritis  Study performed to determine if promethazine effective in preventing PONV & pruritis in a cesarean section population administered intrathecal morphine