Post on 24-Sep-2015
description
Challenges In
Obstetric
Anesthesia
Elizabeth Wong, CRNA, MSN
LEARNING OBJECTIVES
To list the current challenges that CRNAs face
when delivering anesthesia to parturients
To describe methods that enhance the ability of
CRNAs to provide anesthesia to parturients safely
To review your current obstetric practice and
decide which of these methods can enhance your
current practice
domain free image at www.bing.com
Statistics Epidural and Spinal use during Labor:
United States birth statistics analyzed in 2009
4,130,665 births 1,686,213 parturients requested
epidural, spinal, or combined CSE
1,353,572 parturients had a c-section
(most common surgical procedure in
U.S.) www.cdc.gov
Maternal Mortality Statistics
www.cdc.gov
Maternal Hypertension 15%
Anesthesia Closed Claim Analysis
Since closed claim analysis began in 1984 8954 claims
Close Claim Analysis: Metzner et al. 2011 Best Practice and Research Clinical Anesthesiology.
Anesthesia Closed Claim
Analysis
Obstetric Anesthesia Closed Claim Analysis
1990-2003
426 total (58% c-section
and 42% vaginal delivery)
Liability associated with obstetric anesthesia. 2009. Davies et al. Anesthesiology.
Regional Anesthesia involved in 80% of claims while general
anesthesia involved in 17% of claims
Preventable cause: delay in anesthesia care, poor communication
Closed Claim Analysis - AANA
Reviewed cases from 1989 - 1999 and published in 2001
MacRae, M. D., Closed Claim Studies in Anesthesia: A literature review and implications for practice. AANA Journal. 2007.
Obstetric claims 19% - Death - 12%
AANA Position Statement
Position Statement Number 2.6 Administration of
Regional Anesthesia by Certified Registered Nurse
Anesthetists
Updated by the AANA Board 2010
www.aana.com
Challenge #1 - CMS RULE
The administration of medication via an epidural or
spinal route for the purpose of analgesia, during labor
and delivery, is not considered anesthesia and therefore
is not subject to the anesthesia supervision requirements
at 42 CFR 482.52(a).
However, if the obstetrician or other qualified physician
attending to the patient determines that an
operative delivery (i.e., C-section) of the infant is
necessary, it is likely that the subsequent administration
of medication is for anesthesia, as defined above, and the
anesthesia supervision requirements at 42 CFR
482.52(a) would apply."
#2 - Sleep Deprivation
Try performing delicate work without adequate rest!!!
24 hour shifts and busy labor units
24 hour shifts with call from home
24 hour shifts with in-house call
24 hour shifts are the culprit of sleep deprivation
Sleep Deprivation
Effect of work hour reduction on residents live: A
systematic review. Fletcher et al. JAMA. 2005
Sleep deprivation: Implications for Obstetric practice in the
United States. Clark. Am. Journal of Obstetrics and
Gynecology. 2009.
The effect of sleep deprivation on fine motor coordination
in ob/gyn residents. Avalon. et al. Am Journal of Obstetrics
and Gynecology. 2008.
Deconstructing and reconstructing cognitive performance
in sleep deprivation. Sleep medicine review. 2012.
What to do?
Get a good nights sleep before your 24 hour shift
If awakened in middle of the night:
Exercise - if possible. Use the stairwell and go up 1-2 flights,
do some jumping jacks...
Minimize the coffee intake. Drink water.
Do a legs up the wall inversion pose - if possible
Limit # of 24 hour shifts or try to split the shift
Have a 2nd provider on-call when work load excessive
You must have 3 nights of normal sleep to recover
image:: www.stessily.hubpages.com
#3- Loss of resistance: AIR SALINE HANGING DROP PLASTIC vs GLASS SYRINGES
Identification of the epidural space:
Air - 26% - improved LOR end point
Saline - ~ 73% improved LOR end point, fewer dural
punctures, fewer patchy blocks, less PDPH
No difference in pain relief - both deemed equally safe
Hanging drop - 1%
Epidural space identification: a meta-analysis for complications after air versus liquid as the medium for loss of resistance. Schier et al.
2009. International Anesthesia Research Society.
Labor epidural anesthetics comparing loss of resistance with air versus saline: Does the choice matter. Norman et al. 2006 AANA Journal
image:refdag.nl.comt
LOR...
Plastic syringes - smoother bounce, greater ability to
feel loss of resistance, lighter in the hand, does not
break when dropped
Glass syringes - gravel type feeling unless barrel of
syringe is washed with saline, heavy in hand, breaks
when dropped
No literature addressing safety etc.
image: www.bd.com
#4- C-section and the Failed Epidural - Causes
Incorrect primary placement
Secondary migration of catheter after correct placement
Suboptimal dosing of local anesthetic drugs (caveat - be
careful to discern the difference between difficult labor and
request for top-ups -unknown breech presentation - and
failed epidural)
Patient positioning
Use of median versus paramedian approach
Method used for catheter fixation - over shoulder or lateral
Obesity and large fat rolls with skin movement = catheter
migration
Failed Epidural: Causes and Management, J. Hermanides; M. W. Hollmann; M. F. Stevens; P. Lirk, British Journal of Anesthesia, 2012.
Failed Epidural - Management
Increase volume of local anesthetic
Increase concentration of local anesthetic
Add narcotics or epinephrine
Use a PCEA
Position patient in upright position so that sacral
nerves are anesthetized via gravity
If in O. R. either place single shot spinal with 1/2
regular dose or induce general anesthesia.
Failed epidural top-up for cesarean delivery for failure to progress in labor: the plan is to do a single shot spinal. Carvalho. International journal of obstetric anesthesia. 2011.
#5 - Local Anesthetic Toxicity
S & S may not appear for
~30 min
Vigilance is crucial
Standard resuscitative measures
20% Lipid emulsion of 1.5 ml/kg bolus followed by
continuous infusion of 0.25 ml/kg/min for 30-60 min.
The bolus can be repeated 1-2 times if patient is in
asystole
Varela, H & Burns, S. Use of LIpid emulsions for treatment of local anesthetic toxicity: A case report. AANA Journal. 2010
image: www.dailymed.com
#6 - Post-Dural Puncture Headache (syndrome)
First description of PDPH is 100 years ago by Bier
Factors include age, gender, pregnancy, needle type,
needle size, bevel direction, position, needle
orientation to dural fibers, number of attempts
S & S include photophobia, nausea, vomiting, neck
stiffness, tinnitus, diplopia, dizziness, cephalgia
(throbbing, frontal in origin).
Kuczkowski, KM. Post-dural puncture heardache in the obstetric patient: an old problem. New solutions. Minerva Anesthesiology. 2004.
Differential
Nonspecific headache
Caffeine-withdrawal headache
Migraine
Meningitis
Sinus Headache
Pre-eclampsia
Drug withdrawal (amphetamines, cocaine)
Pneumocephalus-related headache
Intracrainial pathology (hemorrhage, venous thrombosis)
Treatment
Theophylline
Caffeine (PO or IV)
Sumatriptan
Epidural saline
Epidural dextran
Subarachnoid catheter - 1. give 10-20 ml saline before
pulling out subarachnoid catheter 2. run a IV saline
infusion at 10 ml/ hour and dc before going home
Epidural blood patch (10-20 ml)
image: www..thelaughingstork.com
#7 - Amniotic Fluid Embolism
AFE first described in 1941
Most catastrophic challenge in OB
Embolic or immunologic in nature?
Resuscitative measures with Factor VIIa, ventricular
assist device, inhaled nitric oxide, cardiopulmonary
bypass, intraaortic balloon pump, extracorporeal
membrane oxygenation
Gist, RS., Stafford, MD., Leibowitz, MD & Bellin Y. Amniotic Fluid Embolism. Anesthesia & Analgesia. 2009.
#8 - Bleeding Disorders
Hemophilia
von Willebrands disease
Idiopathic thrombocytopenic purpura
Anticoagulated patients
Choi, S., Brull, R., Neuraxial Techniques in Obstetric and Non-obstetric Patients with Common Bleeding Disorders. Regional Anesthesia. 2009.
Green, L., Machin SJ. Managing anticoagulated patients during neuraxial aneesthesia. British Journal of Haematology. 2010.
image:.www.haemophelia.org.nz
Coagulopathic - Risks
Platelet count of 80k is safe for placing epidural
Platelet count of 40K is safe for placing spinal
Lower platelet counts may be safe but insufficient data exist
Use provider judgment at lower levels
If common bleeding diatheses - replace factors prior to block
performance
Tread carefully as there is a paucity of information in the literature
vsn Veen et al. The risk of spinal haematoma following neuraxial anaesthesia or lumbar puncture in thrombocytopenic individuals. British Journal of Haematology. 2009.
Choi, S. Neuraxial techniques in obstetric and nonobstetric patients with common bleeding diatheses. Regional Anesthesia. 2009.
Green et al. Managing anticoagulated patients during neuraxial aneaesthesia. British Journal of Haematology. 2010
#9 - Hemorrhage
Uterine Rupture
Vaginal birth after c-section
Repeat c-section
Placenta previa, accreta, or percreta
Coagulopaties
Hepner, DL., Gutsche, BB. Obstetric Hemmorrhage. Current Reviews for Nurse Anesthetists. 1998.
Ridgeway, J., Weyrich DL., Benedetti, TJ. Fetal Heart rate changes associated with uterine rupture. American College of Obtetricians and Gynecolotgists. 2004.
image:www.najms.org
California
California Maternal Quality Care
Collaborative (www.cmqcc.org)
California - ~550,000 annual births -
largest number of births in the nation
OB Hemorrhage Toolkit
#10 - Difficult Epidural or Spinal Placement
Low Spinal (0.5-1 ml marcaine 0.75%,
25 mcg fentanyl sit upright for 3 min) in
lateral position or moving patient and
return later to place epidural when
patient is more calm
Ultrasound (use OB ultrasound) vs blind
placement Carvalho, JCA. Ultrasound-facilitated epidurals and spinals in obstetrics. Anesthesiology Clinics. 2007.
Broadbent, CR., Maxwell, WB., Ferrie R., Wilson DJ., Gawne-Cain & Russell, R. Ability of anaesthetists to identify a marked lumbar interspace. Anaesthesia. 2000
Kline, JP. Ultrasound Guidance in Anesthesia. AANA Journal. 2011.
image:www.sciencephotobibrary.com
image:www.pie.med.utoronot.ca
#11 - DIFFICULT AIRWAY
Bottomline - assume every parturient
is a difficult intubation
The maternal airway may change
during labor. An assessment at the
beginning of labor may not be reliable
when confronted with an emergency c-
section.
Avoid general anesthesia if possible in
the obstetric population.
Follow the difficult airway algorithm
LMA, retrograde, lightwand, fiberoptic.
Just have a video assisted laryngoscope in the obstetric
operating room - best advice.
Questions?
Thanks to Karyn Karp, Mary Davis, Joe Janakes, Vera Hajduk.