Full text of DOI:10.1007/BF03019874

1230
Occasional Survey
Obstetric anesthesia
practice in Canada
Terrance W. Breen MD FRCPC,
Tacie McNeil RN,
Laura Dierenfield
Purpose: To describe obstetric anesthesia in Canada as practiced in 1997: to identify practices at variance with
the literature and the opinions of experts: and to identify questions for future research.
Methods: In 1997, a detailed postal questionnaire asking about the practice of obstetric anesthesia was mailed
to all 1,539 specialist anesthesiologist members of the Canadian Anaesthetists’ Society residing in Canada. Non-
responders were mailed a second questionnaire three months later.
Results: There were 865 completed questionnaires returned for analysis (56.2%). Of these, 522 anesthesiolo-
gists practiced obstetric anesthesia (60.3%). The data were subdivided into those from anesthesiologists with a
full or part-time university based practice (40.1%) and those from a community based practice (59.9%).
University based and community-based anesthesiologists have very similar patterns of practice. Specific areas
where anesthesia practice was different from current recommendations included: (1) information provided when
obtaining consent for labour epidural analgesia, (2) use of opioids and local anesthetics for initiation of epidural
analgesia, (3) use of coagulation testing in preeclampsia, (4) the common use of cutting spinal needles, (5) use of
neuraxial morphine and nonsteroidal anti-inflammatory agents after Cesarean deliveries, (6) optimal treatment of
neuraxial opioid side effects, (7) when to insert an endotracheal tube for general anesthesia after delivery, and (8)
withdrawing epidural catheters through epidural needles.
Conclusions: This survey presents reference data on the practice of obstetric anesthesia in Canada in 1997.
Anesthesiologists with university affiliation have very similar practices to those without university affiliations.
Objectif : Décrire l’anesthésie obstétricale pratiquée au Canada en 1997; identifier les pratiques qui diffèrent des
pratiques documentées et des opinions d’experts et proposer des sujets de recherches ultérieures.
Méthode : En 1997, un questionnaire détaillé sur la pratique de l’anesthésie obstétricale a été posté aux 1 539
anesthésiologistes membres de la Société canadienne des anesthésiologistes résidant au Canada. Trois mois plus
tard, un second questionnaire a été posté à ceux qui n’avaient pas encore répondu.
Résultats : Il y a eu 865 questionnaires remplis et analysés (56,2 %). De ce nombre, 522 provenaient d’anesthé-
siologistes pratiquant l’anesthésie obstétricale (60,3 %). Les données ont été subdivisées selon le lieu de pratique,
en milieu universitaire à temps complet ou partiel (40,1 %) ou en d’autres centres (59,9 %). Les mo-
dèles de pratique étaient très similaires. Certaines activités spécifiques différaient des recommandations courantes : 1)
l’information fournie pour obtenir le consentement à l’analgésie épidurale pendant le travail, 2) l’usage d’opioïdes
et d’anesthésiques locaux pour amorcer l’analgésie épidurale, 3) l’utilisation d’épreuve de coagulation en préé-
clampsie, 4) l’usage courant d’aiguilles rachidiennes tranchantes, 5) l’administration neuraxiale de morphine et
l’usage d’anti-inflammatoires non stéroïdiens après la césarienne, 6) le traitement optimal des effets secondaires
de l’opioïde neuraxial, 7) le moment d’insertion d’une tube endotrachéal pour l’anesthésie générale après l’ac-
couchement et 8) le retrait des cathéters épiduraux au travers de l’aiguille épidurale.
Conclusion : Cette enquête présente des données de référence sur la pratique de l’anesthésie obstétricale au
Canada en 1997. Les anesthésiologistes affiliés ou non à une université ont une pratique très similaire.
From the Department of Anesthesia, Foothills Medical Centre, University of Calgary, Calgary, Alberta, Canada.
Address correspondence to: Dr. Terrance W. Breen, Department of Anesthesiology, DUMC 3094
Duke University Medical Center, Durham, NC 27710, USA. Phone: 919-681-6535; Fax: 919-668-6265; E- mail:
breen003@mc.duke.edu
This study was supported by a grant from the Obstetric Section of the Canadian Anaesthetists’ Society.
Accepted for publication August 17, 2000.
CAN J ANESTH 2000 / 47: 12 / pp 1230–1242

Breen et al.: OBSTETRIC ANESTHESIA IN CANADA
1231
EFERENCE values for the practice of
obstetric anesthesia in Canada have not
been determined. At national and interna-
TABLE I Practice location (province) of anesthesiologists return-
ing questionnaires
Province of
anesthesia
practice
Number of Percentage of Distribution
R
tional meetings, many anesthesiologists are
responses
from each number of
total
of active
specialist
often struck by the differences in practice amongst
their colleagues. New drugs and techniques are being
introduced into practice (e.g., neuraxial opioids,
patient controlled epidural analgesia, combined spinal
epidural analgesia, ropivacaine) and some long-held
beliefs are being re-examined (e.g. timing of epidural
analgesia, test doses, the effect of epidural analgesia on
the progress of labour and method of delivery). The
extent to which new or changing ideas are reflected in
practice is unknown. The purpose of this study was:
(1) to describe obstetric anesthesia as practiced in
Canada in 1997, (2) to identify practices at variance
with the literature and the opinions of experts, and (3)
to identify questions for future research.
province
responses
members of
the CAS
(year 2000)
British Columbia
Alberta
Saskatchewan
Manitoba
Ontario
Québec
New Brunswick
Prince Edward Island
Nova Scotia
Newfoundland
128
89
35
33
286
106
25
3
16.8%
11.7%
4.6%
17.4%
9.0%
3.6%
4.9%
38.6%
17.0%
2.6%
0.3%
5.0%
1.7%
4.3%
37.5%
13.9%
3.3%
0.4%
5.9%
45
12
1.6%
TABLE II Definitions
Methods
Abbreviation
BP
CAS
Definition
Blood pressure
Canadian Anesthesiologists’ Society
Community-based anesthesiologists
Published surveys of obstetric anesthesia practice were
reviewed to design the first draft of a questionnaire.1–4
The questionnaire was circulated at the Obstetric
Section luncheon of the 1996 Canadian Anaesthetists’
Society annual meeting and the results were used to
improve the questionnaire. A revised questionnaire was
then sent to all specialist anesthesiologist members of
the Canadian Anaesthetists’ Society residing in Canada
in February 1997; non-responders were mailed a sec-
ond questionnaire three months later. A copy of the 19-
page questionnaire can be obtained from Dr. Breen.
The data were entered into an SPSS database for sum-
mary. No statistical analysis was attempted.
CBA
Combitube™ A modified esophageal obturator airway
CSE
CVP
ETT
FHR
GA
im
iv
iv PCA
L&D
LFT
LMA
N2O
NICU
NSAID
PCA
PCEA
PROM
RT
Combined spinal epidural
Central venous pressure catheter
Endotracheal tube
Fetal heart rate
General anesthesia
Intramuscular
Intravenous
Intravenous patient controlled analgesia
Labour and delivery unit
Liver function tests
Laryngeal mask airway
Nitrous oxide
Neonatal Intensive Care Unit
Nonsteroidal anti-inflammatory drug
Patient controlled analgesia
Patient controlled epidural analgesia
Prolonged rupture of the membranes
Respiratory therapist
Results
Data were obtained from anesthesiologists working in
each province (Table I) with the return rate mirroring
the number of specialist anesthesiologists in each
province. Practitioners of obstetric anesthesia tended
to be younger, newer into practice and more likely to
have undertaken additional training in obstetric anes-
thesia. Of the 865 anesthesiologists returning ques-
tionnaires, 522 practiced obstetric anesthesia (60.3%).
The data presented in this report come from these
anesthesiologists and are stratified into anesthesiolo-
gists who worked partly or entirely in a university-
TENS
Transcutaneous electrical nerve stimulation
Trach Light™ A flexible stylet with a distal light source that can
be placed at the end of the endotracheal tube
UBA
University-based anesthesiologists, in whole or in
part
Urinary tract infection
UTI
commented upon because of their potential interest or
controversial nature. The reader is referred to stan-
dard texts for information and recommendations on
most questions of the survey.5,6
based
environment
(UBA-
university-based
anesthesiologists) and those who were community
based (CBA – community-based anesthesiologists).
Discussion
Oral intake during labour
This paper presents information covering a diverse
range of obstetric anesthesia topics. Selected items are
Most anesthesiologists (94.5%) allowed some oral
intake in the latent phase of labour (Table IV). During

1232
CANADIAN JOURNAL OF ANESTHESIA
active labour, anesthesiologists became more restric-
tive about the type and amount of oral intake allowed,
a finding similar to a U.S. survey.7 Some authors have
questioned the need for a restrictive practice of oral
intake during labour and Elkington suggested that
“unless parturients are not candidates for regional
anesthesia, a nonparticulate diet should be allowed.”8
A recent review article concluded that, “the incidence
of pulmonary aspiration in general surgical patients is
small, and only slightly greater in obstetric and pedi-
atric patients. The resulting morbidity per anesthetic is
low and mortality very small.”9 Given that pulmonary
aspiration of gastric contents is rare, no restrictive oral
intake policy guarantees an empty stomach, and clear
liquids are rapidly absorbed from the stomach, a more
liberal policy of oral intake of clear liquids during
labour may be considered.
Patient education and consent for labour analgesia
Canadian women want to be informed of all possible
complications associated with epidural analgesia.1 0 We
found that accidental dural puncture was mentioned by >
80% of anesthesiologists, paralysis was mentioned by 56%
of anesthesiologists and death by 22% (Table VI). This
finding contrasts with the Canadian Medical Protective
Association (CMPA) recommendation that patients be
informed of common, non-serious side effects or compli-
cations, and rare but serious complications.1 1
Laboratory evaluation
A majority of anesthesiologists did not require any
laboratory testing before placing a labour epidural
catheter (Table VII). The minimum platelet count
TABLE V Analgesia options available and the use of iv PCA opi-
oid analgesia during labour
CBA
UBA
Epidural analgesia
Intramuscular opioids
Nitrous oxide – oxygen
Showers
Intravenous opioids
Pudendal nerve blocks
Combined spinal epidural
analgesia (CSE)
Bath tubs
Paracervical blocks
TENS
Water blocks
Acupuncture
Hypnosis
280/300 (93.3%) 201/207 (97.1%)
286/295 (96.5%) 191/202 (95.0%)
216/282 (76.6%) 166/194 (85.6%)
219/276 (79.3%) 161/194 (83.0%)
178/270 (65.9%) 170/194 (87.6%)
184/268 (68.7%) 106/170 (59.2%)
TABLE III Comparison between community based and universi-
ty based anesthesiologists who practice obstetric anesthesia
Variable
CBA
UBA
Male/total
Age (yr)
256/310 (82.6%) 159/208 (76.4%)
44.5 11.1
13.3 9.2
44.0 7.5
13.0 7.7
116/252 (46.0%) 156/194 (80.4%)
141/261 (54.0%) 105/185 (56.8%)
117/246 (47.6%) 63/166 (38.0%)
51/234 (21.8%) 59/172 (34.3%)
27/227 (11.9%) 15/161 (9.3%)
Yr practicing anesthesia
Additional training in
obstetric anesthesia
Primary care centre
Secondary care centre
Tertiary care centre
15/311 (4.8%)
60/310 (9.4%)
29/208 (13.9%)
5/208 (2.4%)
182 310 (58.7%) 14/208 (6.7%)
68/310 (21.9%) 187/208 (89.9%)
2/226 (0.9%)
1/224 (0.4%)
13/162 (8.0%)
2/159 (1.3%)
Teach anesthesia residents 89/311 (28.6%) 199/208 (95.7%)
% of practice in OB
11.2%
14.0%
The number of times in
the last year that each
anesthesiologist has
provided iv PCA opioid
analgesia during labour
The number of
Dept. produces labour pain
management brochure
Dept. teaches pain relief in
labour classes
Anesthesiologists cover
OR and OB simultaneously 292/309 (94.5%) 138/207 (66.7%)
Anesthesiologists cover > 1
hospital simultaneously
Manage labour analgesia
from outside the hospital
185/303 (61.1%) 156/200 (78.0%)
72/306 (23.5%) 112/202 (55.4%)
0.4
1.1
anesthesiologists who
have used
35/307 (11.4%) 12/204 (5.9%)
iv PCA fentanyl for
labour analgesia
87/266 (32.7%) 5/197 (2.5%)
16/43 (37.2%)
49/81 (60.5%)
TABLE IV Eating and drinking in labour
Amount of food liquid you allow women to ingest during:
The latent phase of labour
CBA UBA
Active labour
CBA
UBA
Small amounts of clear liquids to clear liquids ad lib 190/301 (63.1%) 133/205 (64.9%)
142/303 (46.9%) 114/204 (55.9%)
124/303 (40.9%) 72/204 (35.3%)
Ice chips only
Light meals
43/301 (14.3%)
38/301 (12.6%)
13/301 (4.3%)
-
29/205 (14.1%)
27/205 (13.2%)
5/205 (2.4%)
-
-
-
No restrictions
Nothing by mouth
-
-
19/303 (6.3%)
14/204 (6.9%)

Breen et al.: OBSTETRIC ANESTHESIA IN CANADA
1233
TABLE VI Risks of epidural analgesia as explained to parturients
significantly.16,17 Some investigators are exploring the
use of thromboelastography (TEG) in the settings of
thrombocytopenia and preeclampsia.18,19 Whether or
not TEG will provide useful information to obstetric
anesthesiologists remains unknown.
CBA
UBA
Dural puncture
Inadequate block
Back pain after delivery
Hypotension
Nerve injury
Paralysis
252/268 (94.0%) 171/183 (93.4%)
182/268 (67.9%) 133/183 (72.7%)
176/268 (65.6%) 128/183 (69.9%)
162/268 (60.4%) 105/183 (57.4%)
151/268 (56.3%) 102/183 (55.7%)
152/268 (56.7%) 100/183 (54.6%)
97/268 (36.2%) 49/183 (26.8%)
Labour epidural analgesia
The majority of anesthesiologists administered a “test
dose” prior to a “labour analgesia” dose (Table IX),
with CBA favouring a bupivacaine and UBA lidocaine-
epinephrine. The need for, and efficacy of, the lido-
caine-epinephrine test dose has been questioned.20–22
Many anesthesiologists favour incremental injection of
epidural medications where each dose administered is
“safe” if inadvertently placed in the subarachnoid or
intravascular spaces.3,23 The lidocaine-epinephrine test
dose has recently been shown to hinder patient mobili-
ty and, therefore, may not be desirable for anesthesiol-
ogists aiming to provide ambulatory epidural analgesia
during labour.2 4 Labour analgesia was most commonly
initiated with bupivacaine 0.25% without opioids.
Studies have shown that by adding a lipophilic opioid
the dose of epidural local anesthetic needed for labour
analgesia can be reduced by up to 50%, often termed
the “bupivacaine sparing effect.”25 These lower doses of
bupivacaine and fentanyl (or sufentanil) have been asso-
ciated with: (1) improved analgesia,2 6 (2) less motor
blockade,2 7 (3) more ambulation,27,28 (4) a decreased
need for oxytocin,2 8(5) a shorter 2nd stage of labour,2 7
(6) fewer instrumental vaginal deliveries,26–29 and (7) a
decreased Cesarean section rate.2 8The UBA were more
likely to use patient controlled epidural analgesia
(PCEA) than CBA (Table X). PCEA has many poten-
tial advantages for labour epidural analgesia, both in
small and large maternity units.30 Patient satisfaction is
high and anesthesiologists get fewer calls for top-ups.
With proper programming and protocols in place,
PCEA may be safely used, even when the anesthesiolo-
gist is out of the hospital or busy in the operating room,
Intravenous injection
Epidural abscess/hematoma 85/268 (31.7%) 55/183 (30.1%)
Allergy
80/268 (29.9%) 53/183 (29.0%)
79/268 (29.5%) 43/183 (23.5%)
72/268 (26.9%) 46/183 (25.1%)
70/268 (26.1%) 30/183 (16.4%)
Total spinal
Pruritus
Death
TABLE VII Laboratory testing and coagulopathy
CBA
UBA
Minimum lab data required to initiate epidural analgesia:
None
CBC
CBC, PT, aPTT
178/308 (57.8%) 137/204 (67.2%)
122/308 (39.6%) 65/204 (31.9%)
4/308 (1.3%) 2/204 (1.0%)
Minimum platelet count you will accept and still provide epidural
analgesia:
Platelet count
80,600 18,800 79,500 18,000
Would place an epidural
catheter if the platelet count
were 50,000
45/308 (14.6%) 33/204 (16.2%)
In what situations do you determine a bleeding time?
Never
197/302 (65.2%) 146/200 (73.0%)
All parturients with platelet
counts < 100,000
Preeclampsia with platelet
counts 100,000-150,000
63/302 (20.9%) 29/200 (14.5%)
13/302 (4.3%) 8/200 (4.0%)
Is thromboelastography (TEG) used in your centre?
No
284/300 (94.7%) 172/201 (85.6%)
Yes, on an experimental basis 12/300 (4.0%)
Yes, it is readily available
25/201 (12.4%)
for clinical use
2/300 (0.7%)
3/201 (1.5%)
a
view supported by the current Canadian
required by most anesthesiologists for placement of an
epidural catheter was 80,000 18,000, and approxi-
mately 15% of anesthesiologists would insert epidural
catheters if the platelet count was as low as 50,000.
The literature now contains several reports of epidur-
al anesthesia in patients with thrombocytopenia,
including one patient with a platelet count of 2,000-
4,000 who received an epidural without seque-
lae.4,12–15 More information is needed to determine
the safety of epidural analgesia in the presence of
thrombocytopenia. Investigations have shown that the
bleeding time does not predict bleeding in remote
sites (e.g., the epidural space) and its use has dropped
Anesthesiologists’ Society Guidelines for Obstetric
Anesthesia. Hospitals and departments of anesthesia
looking to acquire infusion pumps for labour and deliv-
ery suites might want to consider PCEA pumps rather
than simple infusion pumps.
Fever and epidural analgesia and anesthesia
Approximately two thirds of anesthesiologists would
provide epidural analgesia in the presence of moderate
systemic infection (Table XII). However, with a more
severe systemic infection only 45% of anesthesiologists
would place an epidural catheter. While there are data
to support the use of epidural analgesia in the setting

1234
CANADIAN JOURNAL OF ANESTHESIA
TABLE VIII Pulling epidural catheters back through epidural needles
Do you pull epidural catheters back through epidural needles if you are only able to insert the epidural catheters:
1-2 cm through the needle $ 3 cm through the needle
CBA
UBA
CBA
UBA
Uncommonly, and only if there is no resistance
Commonly, but only is there is no resistance
Never
110/310 (35.5%)
101/310 (32.6%)
99/310 (31.9%)
75/205 (36.6%) 59/309 (19.1%)
71/205 (34.6%) 11/309 (3.6%)
59/205 (28.8%) 238/309 (77.3%) 141/203 (69.5%)
47/203 (23.2%)
14/203 (6.9%)
CBA
16/310 (5.2%)
UBA
Percentage having had an epidural catheter break
leaving a piece of catheter in a patient
10/205 (4.9%)
TABLE IX Initiation of labour analgesia
TABLE X Maintenance of labour analgesia
CBA
CBA
UBA
UBA
% providing epidural
analgesia at < 3 cm
% providing epidural
analgesia at 3-7 cm
% providing epidural
analgesia at 8-10 cm
Labour epidural analgesia is maintained by:
166/308 (53.9%) 134/208 (64.4%)
298/307 (97.1%) 204/206 (99.0%)
279/304 (91.8%) 194/204 (95.1%)
Intermittent top-ups
Continuous infusions
Patient Controlled
24/286 (8.3%)
17/195 (8.6%)
238/286 (83.2%) 148/195 (75.9%)
25/195 (12.8%)
Local anesthetic that labour analgesia is maintained with:
Epidural Analgesia (PCEA) 17/286 (5.9%)
Which local anesthetic do you use in your usual test dose?
Bupivacaine 283/286 (99.0%) 192/195 (98.5%)
Concentration of bupivacaine used in infusions to maintain analgesia:
Bupivacaine
Lidocaine
136/295 (46.1%) 56/201 (27.9%)
104/295 (35.3%) 126/201 (62.7%)
0.125%
# 0.10%
108/279 (38.7%) 70/191 (36.6%)
102/279 (36.6%) 93/191 (48.7%)
Do not use a test dose
2-Chloroprocaine
52/295 (17.6%)
2/295 (0.7%)
19/201 (9.5%)
0/201 (0%)
Opioid added to your labour epidural infusions:
Which local anesthetic do you use when initiating labour analgesia?
Fentanyl
Sufentanil
What rate do you run
your labour epidural
infusions at?
202/286 (70.6%) 134/195 (68.7%)
6/268 (2.1%) 16/195 (8.2%)
Bupivacaine
Lidocaine
257/298 (86.2%) 158/201 (78.6%)
29/298 (9.7%) 32/201 (15.9%)
What percentage of bupivacaine do you use to initiate analgesia?
0.25%
0.125%
0.1%
183/256 (71.5%) 104/158 (65.8%)
Average infusion rate
(ml·hr– 1)
9.3 2.3 (n=267) 9.7 2.2 (n=184)
37/256 (14.5%)
9/256 (3.5%)
20/158 (12.7%)
11/158 (7.0%)
Why do you not use patient controlled epidural analgesia (PCEA)
in your practice?
What opioid do you add to the local anesthetic for initiation of
labour analgesia?
Not available
No advantages
Not familiar
173/293 (59.0%) 97/180 (53.9%)
56/293 (19.1%) 48/180 (26.7%)
Fentanyl
Sufentanil
None
111/298 (37.2%) 84/201 (41.8%)
8/298 (2.7%) 8/201 (4.0%)
171/298 (57.4%) 103/201 (51.2%)
28/293 (9.6%)
12/180 (6.7%)
Percentage using CSE
56/301 (18.6%) 88/202 (43.6%)
Why do you not use CSE in your practice?
No advantages
Not available
Not familiar
131/242 (54.5%) 72/119 (60.5%)
infection might be safe!3 8 For a Cesarean section in
the setting of a fever, 55% of anesthesiologists would
use spinal anesthesia for delivery, with 27% of UBAs
and 41% of CBAs using general anesthesia. One labo-
ratory showed that with appropriate antibiotic cover-
age (usually unknown), spinal anesthesia might be
safely performed.39,40 There is a need for more and
better information about the risks and benefits of
epidural and spinal analgesia/anesthesia in the pres-
ence of systemic infection.
47/242 (19.4%)
32/242 (13.2%)
14/119 (11.8%)
15/119 (12.6%)
of presumed chorioamnionitis,31,32 there are very few
data about the safety of epidural analgesia in the set-
ting of severe systemic infection. Epidural analgesia in
parturients is a rare cause of central nervous system
infection with large survey studies showing a very low
incidence of infection.33–37 Indeed, one study suggest-
ed that repeated epidural anesthesia in the presence of

Breen et al.: OBSTETRIC ANESTHESIA IN CANADA
1235
TABLE XI Intrapartum monitoring and neonatal resuscitation
after routine vaginal delivery
TABLE XIII Preeclampsia
CBA
UBA
CBA
UBA
Minimum lab testing required before providing epidural analgesia
to a parturient with preeclampsia (BP 150/95, 1-2 g·day– 1 pro-
teinuria):
Use of continuous fetal heart rate monitoring in “low risk”
women receiving epidural analgesia
CBC, PT, aPTT
CBC, PT, aPTT, LFT
CBC
135/302 (44.7%) 100/201 (49.8%)
69/302 (22.8%) 51/201 (25.4%)
82/302 (27.1%) 37/201 (18.4%)
Almost always
Often
Only after top-ups
Never
204/301 (67.8%) 128/202 (63.4%)
54/301 (17.9%) 31/202 (15.3%)
34/301 (11.3%) 36/202 (17.8%)
None
6/302 (2.0%)
7/201 (3.4%)
8/301 (2.7%)
7/202 (3.5%)
For a parturient with preeclampsia (BP 160/105) that has mildly
elevated LFTs and a falling platelet count (300,000 1st trimester,
125,000 yesterday, 80,000 one hour ago), would you provide
epidural analgesia?
Never
105/305 (34.4%) 76/201 (37.8%)
107/305 (35.1%) 49/201 (24.4%)
41/305 (13.4%) 41/201 (20.4%)
17/301 (5.6%) 13/201 (6.5%)
If repeat platelet count
$ 80,000
Yes, and place epidural
catheter now
If repeat platelet count
$ 60,000
anesthesiologists who
inserted pulmonary artery
catheters in women allowed
to labour in the last year
Number of
If the bleeding time is normal21/305 (6.9%) 7/201 (3.5%)
For a parturient with preeclampsia (BP 160/105) that has mildly
elevated LFTs and a falling platelet count (120,000 yesterday,
80,000 eight hours ago, 58,000 one hour ago), would you pro-
vide epidural analgesia?
2/310 (0.6%)
17/205 (8.3%)
anesthesiologists who
inserted pulmonary artery
catheters to assist with
management during
Cesarean delivery in the
last year
Never
197/302 (74.8%) 155/204 (76.0%)
If repeat platelet count
$ 50,000
29/305 (9.5%) 21/204 (10.3%)
If the bleeding time is normal21/305 (6.9%) 9/204 (4.4%)
Yes, and place the epidural
catheter now
11/305 (3.6%) 5/204 (2.5%)
6/310 (1.9%)
17/205 (8.3%)
What anesthetic is your usual choice for Cesarean section in the
setting of moderate to severe preeclampsia?
Epidural
192/305 (63.0%) 137/200 (68.5%)
70/305 (23.0%) 44/200 (22.0%)
41/305 (13.4%) 16/200 (8%)
Spinal
General
CSE
2/309 (0.6%)
3/205 (1.5%)
TABLE XII Regional analgesia/anesthesia in the presence of fever
Provision of labour epidural analgesia for a patient in the following clinical scenarios:
Suspected UTI (pyuria, T=38.5°C),
Presumed chorioamnionitis (PROM x
4 days, T=39.8°C), on ampicillin and gentam-
icin (morphine 15 mg im one hour ago was
ineffective)
has received two doses of ampicillin
CBA
UBA
CBA
UBA
Provide epidural
Refuse
Wait until afebrile, the provide epidural
210/305 (68.8%)
49/305 (16.1%)
27/305 (8.9%)
138/205 (67.3%)
22/205 (10.7%)
29/205 (14.1%)
16/308 (5.2%)
70/308 (22.7%)
-
21/203 (10.3%)
36/203 (17.7%)
-
Explain risks, provide epidural if wanted 11/305 (3.6%)
11/205 (5.4%)
-
-
127/308 (41.2%)
75/308 (24.4%)
6/308 (2.0%)
66/203 (32.5%)
70/203 (34.5%)
5/203 (2.5%)
iv PCA
-
-
Single intrathecal injection
Anesthesia for Cesarean section in patients without a working epidural catheters who are febrile (T=38.5°C), presumed to have chorioam-
nionitis, and have received two doses of ampicillin:
CBA
UBA
Spinal
156/309 (50.5%)
126/309 (40.8%)
25/309 (8.1%)
3/309 (0.6%)
128/205 (62.4%)
56/205 (27.3%)
18/205 (8.8%)
3/205 (1.5%)
General
Epidural
CSE

1236
CANADIAN JOURNAL OF ANESTHESIA
TABLE XIV The frequency with which anesthesiologists would
provide epidural analgesia in a number of uncommon medical
conditions
TABLE XV Anesthesia for elective Cesarean section
CBA UBA
Usual anesthetic technique for elective Cesarean section:
CBA
UBA
Spinal
249/306 (81.4%) 181/205 (88.3%)
45/306 (14.7%) 19/205 (9.3%)
Epidural
General
CSE
Harrington rods
Multiple sclerosis
200/302 (66.2%) 161/201 (80.1%)
231/302 (76.5%) 180/204 (88.2%)
6/306 (2.0%)
4/306 (1.3%)
1/205 (0.5%)
3/205 (1.5%)
Sciatica during the last
month of pregnancy
Previous lumbar disc surgery280/307 (91.2%) 192/201 (95.5%)
Recent history of a
prolapsed lumbar disc
“Stable” thoracic spine
fracture in a neurologically
intact parturient
268/304 (88.2%) 180/201 (89.6%)
Usual type of spinal needle used:
Quincke
Sprötte
207/272 (76.1%) 151/195 (77.4%)
32/272 (11.8%) 21/195 (10.8%)
202/300 (67.3%) 135/202 (66.8%)
Whitacre
24/272 (8.8%)
17/195 (8.7%)
Gauge of spinal needle most commonly used:
190/299 (63.5%) 148/198 (74.7%)
232/301 (77.1%) 171/198 (86.4%)
65/291 (22.3%) 51/197 (25.9%)
25G
27G
24G
26G
177/273 (64.8%) 110/195 (56.4%)
42/273 (15.4%) 48/195 (24.6%)
29/273 (10.6%) 17/195 (8.7%)
Paraplegia
Intracranial tumour
Recent intracranial
hemorrhage, aneurysm, not
clipped
Positive HIV status
AIDS
15/273 (5.5%)
13/195 (6.7%)
Local anesthetic most commonly used for spinal anesthesia?
116/292 (39.7%) 95/199 (47.7%)
229/300 (76.3%) 172/204 (84.3%)
210/298 (70.5%) 163/203 (80.3%)
Bupivacaine
Lidocaine
197/269 (73.2%) 186/195 (95.4%)
62/269 (23.0%) 8/195 (4.1%)
% adding fentanyl to
spinal local anesthetics
Moderate aortic stenosis
2
140/208 (67.3%) 116/178 (65.2%)
(valve area 1-1.5 cm )
246/302 (81.5%) 177/203 (87.2%)
68/296 (23.0%) 86/204 (42.2%)
Severe aortic stenosis
Epidural anesthesia for Cesarean section:
2
(valve area < 1 cm )
% using CO lidocaine
167/297 (56.2%) 116/205 (56.6%)
85/297 (28.2%) 64/205 (31.2%)
35/297 (11.8%) 15/205 (7.3%)
2
Significant pulmonary
hypertension
Eisenmenger’s syndrome
% using plain lidocaine
% using bupivacaine
% adding fentanyl to
epidural local anesthetic
133/285 (46.7%) 151/201 (75.1%)
79/285 (27.7%) 106/195 (54.4%)
200/297 (67.3%) 143/205 (69.8%)
Use of phenylephrine to treat hypotension after major conduction
block
Preeclampsia
% using phenylephrine
% using phenylephrine
# 10% of the time
95/283 (33.6%) 94/191 (49.2%)
Almost one half of anesthesiologists wanted to review a
CBC, PT and aPTT before providing epidural analgesia
in the setting of preeclampsia (Table XIII). In
preeclamptic patients, thrombocytopenia occurs before
abnormalities are detected in the PT and aPTT and a
normal platelet count is highly predictive of a normal PT
and aPTT.4 1 – 4 3 Therefore, if the platelet count is normal,
a PT and aPTT are not needed. In the setting of severe
preeclampsia, 65% of anesthesiologists would use epidur-
al anesthesia for Cesarean delivery and 23% spinal anes-
thesia. A recent retrospective study suggested that spinal
anesthesia may be safely used in these patients.4 4
Although most anesthesiologists believe general anesthe-
sia should be avoided, if possible, especially because of
airway concerns, the literature does support appropriate
use of general anesthesia in severe preeclamptic patients.
78/95 (82.1%) 80/94 (85.1%)
(Table XV). In general, fewer and less severe post
dural puncture headaches are seen with non-cutting
spinal needles.48–50 In addition, smaller needles pro-
duce fewer and less severe headaches than larger nee-
dles but bend more easily. Thus, the smallest
non-cutting needle that allows easy access to the cere-
brospinal fluid is recommended.
Urgent and emergency Cesarean delivery
Cesarean deliveries are frequently urgent or emergency
operations. When anesthesiologists have 10-15 min,
more than 95% would use a working epidural catheter
(Table XVI). In the same situation but without a work-
ing epidural catheter, 17% of CBA would choose gen-
eral anesthesia, as would 6% of UBA. Current literature
suggests that maternal mortality, especially in the emer-
gency situation, is considerably higher with general
anesthesia than with regional anesthesia.51,52
45,46
Thus, anesthesiologists should assess each patient
and choose the form of anesthesia with which they are
most comfortable and familiar.4 7
Anesthesia for Cesarean delivery
Most anesthesiologists used spinal anesthesia for elec-
tive Cesarean sections (84%) and Quincke spinal nee-
dles were used for more than ¾ of spinal anesthetics

Breen et al.: OBSTETRIC ANESTHESIA IN CANADA
1237
TABLE XVI Anesthesia for urgent and emergency (stat) Cesarean section
Anesthesia most commonly chosen for an urgent Cesarean section when you have 10-15 min before skin incision:
Working epidural catheter in situ
No epidural catheter in situ
CBA
UBA
CBA
UBA
Epidural
Spinal
General
CSE
292/307 (95.1%)
9/307 (2.9%)
6/307 (2.0%)
-
199/205 (97.1%)
5/205 (2.4%)
1/205 (0.5%)
-
13/309 (4.2%)
243/309 (78.6%)
53/309 (17.2%)
0/309 (0%)
4/205 (2.0%)
186/205 (90.7%)
13/205 (6.3%)
2/205 (1.0%)
Anesthesia most commonly administered for a stat Cesarean section (FHR = 60 for two minutes):
Working epidural catheter in situ No epidural catheter in situ
CBA
UBA
CBA
UBA
General
Spinal
Epidural
184/307 (59.9%)
7/307 (2.3%)
116/307 (37.8%)
108/203 (53.2%)
13/203 (6.4%)
81/203 (39.9%)
282/308 (91.6%)
26/308 (8.4%)
-
171/204 (83.8%)
33/204 (16.2%)
-
TABLE XVII Management of inadequate regional anesthesia for Cesarean section
When the patient is not yet prepped for surgery and the epidural block is inadequate, your usual approach is:
CBA
UBA
Spinal
General
Repeat the epidural
125/302 (41.4%)
143/302 (47.4%)
34/302 (11.3%)
121/202 (58.9%)
63/202 (31.2%)
18/202 (8.9%)
When you give a spinal anesthetic after a failed epidural anesthetic, your dose of intrathecal local anesthetic is:
CBA
UBA
Decreased
Not changed
97/230 (42.2%)
133/230 (57.8%)
94/172 (54.7%)
78/172 (45.3%)
When the block is inadequate, your first strategy to manage the anesthetic is:
Before delivery of the baby
After delivery of the baby
CBA
UBA
CBA
UBA
GA with ETT
N2O other
Ketamine other
Reassure
Opioid other
Propofol other
Local anesthesia infiltration of the wound
Midazolam other
153/305 (50.2%)
50/305 (16.4%)
22/305 (7.2%)
26/305 (8.5%)
22/305 (7.2%)
14/305 (4.6%)
16/305 (5.2%)
-
93/200 (46.5%)
40/200 (20.0%)
29/200 (14.5%)
14/200 (7.0%)
12/200 (6.0%)
4/200 (2.0%)
2/200 (1.0%)
-
87/295 (29.5%)
14/295 (4.7%)
13/295 (4.4%)
5/295 (1.7%)
128/295 (43.4%)
36/295 (12.2%)
-
67/199 (33.7%)
10/199 (4.9%)
23/199 (11.6%)
2/199 (1.0%)
83/199 (41.7%)
7/199 (3.5%)
-
6/295 (2.0%)
4/199 (2.0%)
Spinal anesthesia after inadequate epidural anesthesia
When an inadequate epidural block was detected before
preparing a patient for surgery, 49% of anesthesiologists
would remove the epidural catheter and administer a
spinal anesthetic (Table XVII). Approximately half of
those anesthesiologists would use their usual spinal dose
of local anesthetic and half a lower dose. The use of a
lower dose of local anesthetic reflects the possible
increased risk of high spinal anesthesia when a spinal
anesthetic is used after a failed epidural anesthetic.5 3
Failure to intubate the trachea or ventilate the lungs
during Cesarean delivery
In the setting of an elective Cesarean section under
general anesthesia when the anesthesiologist could
ventilate but not intubate the patient’s trachea, 60% of
anesthesiologists would awaken the patient immedi-
ately and switch to regional anesthesia (Table XVIII).
A panel of Canadian anesthesiologists recently recom-
mended “after two failed attempts at oral intubation,
if it is possible to ventilate the lungs by face mask with

1238
CANADIAN JOURNAL OF ANESTHESIA
TABLE XVIII First step in the management of unable to intubate/unable to ventilate situations
Elective Cesarean sections
Can ventilate, cannot intubate
Cannot ventilate, cannot intubate
CBA
UBA
CBA
UBA
Awaken patient, provide regional anesthesia
Trach Light™ assisted intubation
Fibreoptic assisted endotracheal intubation
Gum elastic bougie assisted tracheal intubation
LMA
188/307 (61.2%)
35/307 (11.4%)
20/307 (6.5%)
26/307 (8.5%)
24/307 (7.8%)
-
115/199 (57.8%)
28/199 (14.1%)
23/199 (11.6%)
16/199 (8.0%)
10/199 (5.0%)
-
175/302 (57.9%)
17/302 (5.6%)
14/302 (4.6%)
11/302 (3.6%)
64/302 (21.2%)
9/302 (3.0%)
91/195 (46.7%)
20/195 (10.3%)
14/195 (7.2%)
7/195 (3.6%)
44/195 (22.6%)
5/195 (2.6%)
Transtracheal jet ventilation
Stat Cesarean sections
Can ventilate, cannot intubate Cannot ventilate, cannot intubate
CBA
UBA
CBA
UBA
LMA
121/309 (39.2%)
53/309 (17.2%)
37/309 (12.0%)
33/309 (10.7%)
28/309 (9.1%)
7/309 (2.3%)
3/309 (1.0%)
-
62/200 (31.0%)
42/200 (21.0%)
23/200 (11.5%)
25/200 (12.5%)
19/200 (9.5%)
4/200 (2.0%)
6/200 (3.0%)
-
124/306 (40.5%)
36/306 (11.8%)
16/306 (5.2%)
-
81/200 (40.5%)
31/200 (15.5%)
7/200 (3.5%)
-
Trach Light™ assisted intubation
Fibreoptic assisted endotracheal intubation
Face mask general anesthesia
Gum elastic bougie assisted tracheal intubation
Awaken patient, provide regional anesthesia
Combitube™
-
-
58/306 (19.0%)
3/306 (1.0%)
10/306 (3.3%)
8/306 (2.6%)
24/200 (12.0%)
10/200 (5.0%)
4/200 (2.0%)
4/200 (2.0%)
Transtracheal jet ventilation
Tracheostomy
-
-
TABLE XIX Analgesia after Cesarean delivery
mask airway (LMA) or Combitute™ to establish ven-
tilation, proceeding if needed to a transtracheal airway.
CBA
UBA
Most common method of providing analgesia after Cesarean section:
Analgesia after Cesarean delivery
Neuraxial morphine
im opioids
iv PCA opioids
176/309 (57.0%) 157/201 (78.1%)
86/309 (27.8%) 22/201 (10.9%)
33/309 (10.7%) 16/201 (8.0%)
Approximately two thirds of anesthesiologists reported
using neuraxial morphine to provide analgesia after
Cesarean delivery (UBA 78% vs CBA 57%, Table XIX).
While late onset respiratory depression was once feared
after neuraxial morphine, with appropriate monitoring
guidelines, neuraxial morphine is a safe, effective and
easily used method for providing excellent analgesia
after Cesarean delivery.55–57 Nonsteroidal anti-inflam-
matory drugs (NSAIDs) were used by 59% of anesthe-
siologists (73% UBAs vs 46% CBAs). The NSAIDs
improve analgesia and allow a smaller dose of morphine
to be used, decreasing the side effects.58–61 While
diphenhydramine was used by more than 50% of anes-
thesiologists to treat pruritus following neuraxial opi-
oids, evidence suggests that nalbuphine is a better
choice.62–64
PCEA or epidural infusions 6/309 (1.9%)
0/201 (0%)
Adjuncts routinely ordered as part of postoperative analgesia:
Codeine acetaminophen 138/176 (78.4%) 99/157 (63.1%)
NSAIDs
81/186 (46.0%) 114/157 (72.6%)
62/176 (35.2%) 62/157 (39.5%)
Acetaminophen
iv PCA opioids
im opioids
16/176 (9.1%)
5/176 (2.8%)
2/176 (1.1%)
14/157 (8.9%)
6/157 (3.8%)
3/157 (1.9%)
PCEA
Do the surgeons usually
infiltrate the incision with
local anesthesia for
postoperative analgesia?
19/305 (6.2%)
11/205 (5.4%)
Drug used most commonly to treat neuraxial opioid-induced pruritus:
Diphenhydramine
Naloxone
No drug treatment
Nalbuphine
176/298 (59.1%) 112/202 (55.4%)
45/298 (15.1%) 35/202 (17.3%)
42/298 (14.1%) 21/202 (10.4%)
24298 (8.1%)
25/202 (12.4%)
Anesthesia after delivery
General anesthesia without an endotracheal tube was
often used for manual removal of a retained placenta
(Table XXI) - a very curious finding as most parturi-
ents in the immediate postpartum period are still con-
sidered “full stomach patients.”65 In contrast, the
median duration following delivery before anesthesi-
ologists would provide anesthesia for a tubal ligation
cricoid pressure applied, the patient should be woken
up.”5 4When the trachea could not be intubated or the
lungs ventilated, 53.5% of anesthesiologists stated that
their first step would be to awaken the patient. The
expert panel recommended that anesthesiologists
maintain cricoid pressure and use either a laryngeal

Breen et al.: OBSTETRIC ANESTHESIA IN CANADA
1239
TABLE XX Placenta previa and anesthesia for Cesarean section
Preferred anesthetic for an elective Cesarean section in a patient who has a placenta previa:
Posterolateral placenta previa
Anterior placenta previa
CBA UBA
CBA
UBA
Spinal
174/305 (57.0%)
54/305 (17.7%)
74/305 (24.3%)
3/305 (1.0%)
111/202 (55.0%)
54/202 (26.7%)
29/202 (14.4%)
8/202 (4.0%)
60/300 (20.0%)
38/300 (12.7%)
197/300 (65.7%)
5/300 (1.7%)
38/201 (18.9%)
38/201 (18.9%)
118/201 (58.7%)
7/201 (3.5%)
Epidural
General
CSE
Additional access or monitoring lines used in the above settings:
CBA
UBA
CBA
UBA
2nd iv
Arterial line
CVP
268/279 (96.1%)
27/154 (17.5%)
12/149 (8.1%)
187/189 (98.9%)
18/106 (17.0%)
4/97 (4.1%)
283/291 (97.3%)
102/188 (54.3%)
59/172 (34.3%)
191/193 (99.0%)
95/146 (65.1%)
38/115 (33.0%)
TABLE XXI Anesthesia in the early postpartum period
CBA UBA
have been different response rates from large hospital
settings compared with that from smaller hospital set-
tings. If a large group all answered questions in a simi-
lar fashion, that group may have influenced the results.
However, given the size of the survey, number of
responses, and resources of the investigators, it was not
possible to reduce the data to responses from each cen-
tre and to reanalyze the data in that fashion. The data
represents the opinions of a large number of practicing
specialist anesthesiologists from all parts of the country,
and therefore probably reflects common practice.
Usual anesthetic for manual removal of the placenta in stable (not
bleeding) patients without an epidural catheters in situ:
GA without ETT
Spinal
GA with ETT
CSE
199/309 (64.4%) 93/205 (45.5%)
52/309 (16.8%) 58/205 (28.3%)
25/309 (8.1%)
15/309 (4.9%)
13/309 (4.2%)
38/205 (18.0%)
10/205 (4.9%)
6/205 (2.9%)
iv nitroglycerin
Usual anesthetic for postpartum tubal ligations (0-24 hr after
delivery):
Spinal
General
Epidural
125/302 (41.4%) 121/202 (62.4%)
143/302 (47.4%) 63/202 (31.2%)
34/302 (11.3%) 18/202 (8.9%)
Conclusion
Median number of weeks
required before you will
provide anesthesia, without
endotracheal intubation,
for a tubal ligation:
This study provides reference data for the practice of
obstetric anesthesia in Canada. Each anesthesiologist
practicing obstetric anesthesia now has the opportunity
to compare his/her own practice to this large peer
group. The authors hope the study will stimulate anes-
thesiologists to examine their practice, pursue research to
answer clinical questions, and to improve the care given
to parturients. In particular, anesthesiologists may wish
to: (1) provide more information to labouring women,
(2) reconsider the use of test doses, (3) use opioids plus
local anesthetics for initiation of epidural analgesia, (4)
use PCEA to facilitate maintenance of labour epidural
analgesia, (5) order fewer PT and aPTT tests, (6) use
non-cutting spinal needles, (7) use neuraxial morphine
plus NSAIDs for analgesia after Cesarean deliveries, (8)
use nalbuphine rather than diphenhydramine to treat
neuraxial morphine side effects, and (9) review the role
of general anesthesia without a protected airway in the
early postpartum period.
20
17
and not require an endotracheal tube was approxi-
mately four months.
Limitations
The purpose of this study was to describe obstetric
anesthesia as practiced in Canada during 1997. The sur-
vey methodology has several limitations. The overall
response rate to the questionnaires was 56%, and of
those, 60% practiced obstetric anesthesia. While this was
fewer than 35% of the anesthesiologists practicing in
Canada, it does represent the opinions of over 500
anesthesiologists. Some groups may have been over
represented in this survey and others under represent-
ed. For example, subspecialist obstetric anesthesiolo-
gists may have responded at a greater rate than
generalist anesthesiologists (or vice versa). There may
have been more (or fewer) responses from UBA than
CBA, and, for different reasons. Similarly, there might
Acknowledgments
The authors want to thank Dr. Peter Samuels for his
help with the development of the original question-
naire, Dr. Sandy Shysh for help with SPSS and the

1240
CANADIAN JOURNAL OF ANESTHESIA
16 Rodgers RPC, Levin J. A critical reappraisal of the
bleeding time. Semin Thromb Hemost 1990; 16:
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17 Lind SE. The bleeding time does not predict surgical
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Canadian Anaesthetists’ Society for providing address
labels of Canadian specialist anaesthetist members. In
addition, we thank all those anesthesiologists who
took time to answer the questionnaire.
18 Sharma SK, Philip J. The effect of anesthetic tech-
niques on blood coagulability in parturients as mea-
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20 Norris MC, Fogel ST, Dalman H, Borrenpohl S, Hoppe
W, Riley A. Labor epidural analgesia without an
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21 Norris MC, Ferrenbach D, Dalman H, et al. Does epi-
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22 Birnbach DJ, Chestnut DH. The epidural test dose in
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