Appendix A: Characteristics of studies included for analysis
Buckenmaier 2010
Methods
Participants
Block
Outcomes
Prospective, randomized, double-blind comparative
trial. Enrolled and assigned to treatment group by
Investigational Pharmacy team member.
Anesthesiologists, patients, and assessors remained
blinded. Study solution prepared by Investigational
Pharmacy.
73 adults, ASA status not specified, undergoing
unilateral breast surgery for early breast cancer. 94
patients enrolled, 21 excluded, 73 analyzed.
Single paravertebral injections at T1 and T6 with
5ml ropivacaine 0.1%. T3 block with 0.3 ml/kg
ropivacaine 0.5% followed by catheter placement at
T3, infusion at 10ml/hr 0.1% ropivacaine, 0.2%
ropivacaine, or normal saline for 72 hours. Block
used for surgical anesthesia.
Evaluations performed at baseline and on days 1, 3,
5, and 7 postoperatively. Evaluation included worst
postoperative pain (VAS 0-10), Perioperative Profile
of Mood State (POMS-SV, scale 0-120), McGill pain
questionnaire score (scale 0-78), symptom distress
score (SDS, scale 10-50), proportion of patients with
nausea and vomiting scores > 1 (part of McCorkle
SDS), return to regular diet, return to activities of
daily living (ADL), return to full employment, and
total opioid use through POD 7.
McGill Pain Questionnaire rates sensory, affective, and evaluative
descriptors of subjective appraisal of pain and quantification of
pain. The word in each subclass implying the least pain = 1, and so
on (range 0-78).
POMS = 65 items based on a 5-point scale ranging from 0 (not at
all) to 4 (extremely) describing six mood states: tension-anxiety (T),
depression-dejection (D), anger-hostility (A), vigor-activity (V),
fatigue-inertia (F), and confusion-bewilderment (C). POMS-SV
(shortened version), was used.
McCorkle SDS = 10-item scale measuring degree of distress with 10
symptoms: nausea, mood, appetite, insomnia, pain, mobility,
fatigue, bowel pattern, concentration, and appearance.
Quality Score
(13 max.)
11
Notes
5 subjects excluded post-randomization for the
following reasons:
Results (cPNB/ssPNB)
N (0.2% Ropivacaine infusion) : 26
N (0.1% Ropivacaine infusion): 26
N (Normal saline): 21
0.2% and 0.1% Ropivacaine groups combined for our
analysis.
2 regional anesthesia complications: one Horner’s
syndrome, one with arm numbness resolving in < 1
week (treatment group not specified).
(0.2% Ropivacaine/0.1% Ropivacaine/NS)
Worst postoperative VAS POD 1•: 2.5/2.7/2.8*
Worst postoperative VAS POD 3•: 2.2/2.4/1.8
Worst postoperative VAS POD 5•: 1.8/2.5/1.7
Worst postoperative VAS POD 7•: 1.2/2.7/1.9
Total mg morphine equivalent used•: 41.4/43.7/36.2
McGill score POD 1 •: 6/5/5
McGill score POD 3•: 5/6/4
McGill score POD 5•: 5/7/4
McGill score POD 7•: 3/9/5
McCorkle SDS score POD 1•: 20/19/20
McCorkle SDS score POD 3•: 16/17/18
McCorkle SDS score POD 5•: 16/17/16
McCorkle SDS score POD 7•: 14/17/16
POMS-SV score POD 1•: 18/20/19
POMS-SV score POD 3•: 17/20/18
POMS-SV score POD 5•: 17/19/20
POMS-SV score POD 7•: 16/21/20
% nausea and vomiting scores > 1 POD 1: 22/46/24
% nausea and vomiting scores > 1 POD 3: 23/22/23
% nausea and vomiting scores > 1 POD 5: 16/18/10
% nausea and vomiting scores > 1 POD 7: 8/26/24
% returning to regular diet immediately: 96/96/90
% returning to regular diet POD 1: 4/4/10
% returning to ADL immediately: 8/12/0
% returning to ADL week 1: 92/81/100
% returning to ADL week 2: 0/8/0
% returning to full employment week 1: 35/46/40
% returning to full employment week 2: 50/29/25
% returning to full employment week 3: 15/17/10
% returning to full employment > 3 weeks: 0/8/25
Conversion from RA to GA: 3/2/4
-1 block technique (catheter thread after SS block)
-1 intent to treat (5 patients excluded after
randomization)
1 -refused operation
1- sought care at different institution
1- became ineligible due to chemotherapy
1- CPVB discontinued postoperatively due to leaking
catheter
1- unreliable data
Multimodal analgesia included scheduled
Acetaminophen and an NSAID.
Elliot 2010
Methods
Participants
Block
Outcomes
Prospective, double-blind, comparative trial.
Patients, anesthesiologists and assessors were
blinded. Randomization described as sequential
sealed envelopes.
54 patients, ASA unspecified, undergoing ankle and
hindfoot surgery.
GA was induced prior to block. Initial bolus 0.5%
bupivacaine 20ml, then popliteal catheter was
thread. ssPNB group received continuous saline
infusion and cPNB group received 0.25%
bupivacaine 4ml/hr with 1ml/hr patient controlled
bolus for 72 hours. All patients also received
saphenous block at the level of the knee with 0.5%
bupivacaine 10ml.
Subjects recorded VAS pain scores three times daily
for 72 hours postoperatively. Requirement for
supplemental opioid analgesia and complications
were recorded.
Quality Score
(13 max.)
8
Notes
No major complications as a result of the block.
One patient in placebo group experienced
accidental dislodgement of the catheter after 48
hours.
Fredrickson 2010
Methods
Participants
Block
Prospective, randomized, comparative trial.
Computerized randomization. Patient and
anesthesiologist were not blinded. Surgeon and
assessor were blinded.
68 ASA I-II patients undergoing arthroscopic
subacromial decompression, lateral clavicle
excision, or stabilization.
Ultrasound guided interscalene block with 30ml
ropivacaine 0.5% through catheter for both groups.
Surgery under general anesthesia. Catheter
placement preoperatively. Randomization
postoperatively, then catheter removed from
patients in SS group. The cPNB group received
ropivacaine 0.2% at 2ml/hr with 5ml per hour
demand dose for 48 hours.
Results (cPNB/ssPNB)
N (cPNB) = 27
N (ssPNB) = 27
mg morphine used on POD 0†: 10/10
mg morphine used on POD 1†: 10/15
mg morphine used on POD 2†:10/20*
mg morphine used on POD 3†: 7.5/10*
total mg morphine used POD 1-3†: 30/52.5*
VAS POD 0†: 1.2/1.0
VAS POD 1†: 1.7/3.7*
VAS POD 2†: 1.3/2.8*
VAS POD 3†: 1.1/2.6*
Nights as inpatient†: 1/2
-3: Randomization (methods not described).
-1: anesthetic care (care in study and control group
not described or compared).
-1: technique (catheter thread after SS block).
Results (cPNB, ssPNB)
N (cPNB) = 31
N (ssPNB) = 30
Outcomes
Patients questioned on POD 1 and 2 for numeric
pain score, tramadol consumption, arm numbness
(0 = no numbness, 10 = very numb), arm weakness
(0 = no weakness, 10 = 100% weak), numb patient
satisfaction (0 = very unsatisfied, 10 = 100%
satisfied), proportion of night slept (0 = no sleep,
100 = 100% sleep), and adverse effects.
Quality Score
(13 max.)
10
Notes
One patient in SS group required block replacement
in PACU. One patient in SS group was hospitalized
for 2 nights with severe pain and was treated with
supplemental IV opioid until a perineural catheter
was placed on POD 2, thereafter no opioid was
needed.
Multimodal analgesia included scheduled
acetaminophen and diclofenac.
Frassanito 2009
Methods
Participants
Block
Outcomes
Prospective, randomized comparative trial.
Randomization by computer generated table.
Anesthesiologists and patients unblinded. Assessor
not identified in study.
44 patients, ASA I-III, undergoing total knee
arthroplasty under regional anesthesia with
sedation.
PNS guided lumbar plexus block with 0.6%
ropivacaine as single injection of 30ml versus single
injection of 30ml followed by catheter placement
and infusion of ropivacaine 0.2% at 10ml/hr for 48
hr. All patients received single injection sciatic
nerve block.
Assessed in PACU; on arrival to ward; and at 6, 12,
24, 36, 48, and 72 hours after the start of surgery.
Noted VAS score, tramadol consumption,
nausea/vomiting, motor power, and ambulation.
Primary endpoint was ability of block to provide
surgical anesthesia for TKA.
Worst pain with movement POD 1 †: 2/4*
Worst pain with movement POD 2 †: 3/5
Worst pain at rest POD 1 †: 1/2*
Worst pain at rest POD 2 †: 4/3
Average pain POD 1 †: 1/2*
Average pain POD 2 †: 2/2
Tramadol tablets required POD 1†: 0/1*
Tramadol tablets required POD 2†: 0/1*
# taking 0 tramadol tablets POD 1: 24/10
# taking 1 tramadol tablet POD 1: 5/10
# taking ≥ 2 tramadol tablets POD 1: 2/10
# taking 0 tramadol tablets POD 2: 23/13
# taking 1 tramadol tablets POD 2: 2/5
# taking ≥ 2 tramadol tablets POD 2: 6/12
Proportion of night slept POD 1†: 70/45
Proportion of night slept POD 2†: 80/75
# with nausea on POD 1: 4/8
# with nausea on POD 2: 5/4
Arm numbness score on POD 1†: 9/8.5**
Arm numbness score on POD 2†: 3/0**
Arm weakness score on POD 1†: 9/7
Arm weakness score on POD 2†: 6/5
Satisfaction score†: 9/9
# new neurologic symptoms reported on POD 10: 1/3
# patients reporting pain > 6 by NRS on POD 0: 1/5
# with NRS > 6 on POD 1: 1/5
-1: block technique (no true SS group).
-2: blinding (anesthesiologists and patients not
blinded).
The proportion of patients undergoing specific
procedure types was comparable:
Subacromial decompression: 5/6
Excision of lateral clavicle: 4/4
Labral repair: 22/20
Results (cPNB/ssPNB)
N (cPNB) = 22
N (ssPNB) = 22
Pain (VAS) at 6 hr•: 0.4/0
Pain (VAS) at 12 hr•: 1.7/1.6
Pain (VAS) at 24 hr•: 3.7/5.1
Pain (VAS) at 36 hr•: 4.8/3.1
Pain (VAS) at 48 hr•: 3.2/1.7
Total mg tramadol consumption •: 185/236
# requiring intraoperative remifentanil infusion: 5/3
Quality Score
(13 max.)
Notes
9
2 patients in each group experienced bilateral
spread of block. One case was associated with SBP
< 90mm Hg.
Multimodal analgesia included scheduled
acetaminophen.
Mariano 2009
Methods
Participants
Block
Outcomes
Quality Score
(13 max.)
Notes
Time to perform block•: 11.3/10.9
% of patients with nausea•: 18/27
% of patients with vomiting•: 4/13
# bilateral block: 2/2
-1: technique (catheter thread after SS block).
-3: blinding (methods not described).
Prospective, randomized, double-blind comparative
trial. Randomization by computer generated table.
Identical study solutions prepared by Investigational
Pharmacy. Investigators, patients, and clinical staff
unaware of group allocation.
32 subjects undergoing shoulder surgery were
enrolled. Two excluded when unable to obtain
motor response with PNS at time of block
placement.
Interscalene block performed with 40ml ropivacaine
0.5% through the catheter in both groups.
Continuous infusion of ropivacaine 0.2% or NS at
8ml/hr + 4ml bolus every 30 minutes until 400ml
solution used or no later than afternoon of POD 2.
All subjects underwent general anesthesia for
surgery.
Subjects were telephoned on the evening of surgery
and each postoperative afternoon through POD 3.
Outcomes were VAS pain score (scale 0-10), mg
oxycodone consumed, sleep quality, satisfaction (0
= not satisfied, 10 = very satisfied).
12
2 patients receiving continuous infusion
experienced mild shortness of breath on POD 1
which resolved after decreasing the infusion from 8
to 4 ml/hr.
1 patient in ssPNB group requested disenrollment
due to catheter site pain which improved after
catheter removal.
Results (cPNB/ssPNB)
N (cPNB) = 15
N (ssPNB) = 15
Average pain on POD 0†: 0/0
Average pain on POD 1†: 0/3*
Average pain on POD 2†: 0/4*
Average pain on POD 3†: 2/3
Worst pain on POD 0†: 0/0
Worst pain on POD 1†: 4/7.5*
Worst pain on POD 2†: 2.8/8*
Worst pain on POD 3†: 5/6
Least pain on POD 0†: 0/0
Least pain on POD 1†: 0/3*
Least pain on POD 2†: 0/1*
Least pain on POD 3†: 2/1
Satisfaction with analgesia†: 10/7*
# awakenings per night POD 0†: 0/0*
# awakenings per night POD 1†: 0/0*
# awakenings per night POD 2†: 0/0
Mg oxycodone consumed POD 0†: 0/0
Mg oxycodone consumed POD 1†: 0/20*
Mg oxycodone consumed POD 2†: 0/30*
Mg oxycodone consumed POD 3†: 25/15
-1: technique (no true SS group).
1 patient returned to surgical center for discomfort
at site when attempting to remove catheter. The
catheter was removed by anesthesiologist under
local without complication.
Multimodal analgesia included ketorolac.
Williams (2009, 2007, 2006)
Methods
Participants
Block
Outcomes
Prospective, randomized, double-blind comparative
trial. Randomization assignments generated by
computer program. Anesthesiologists, patients, and
assessors remained blinded.
270 patients, ASA I-II, undergoing ACL
reconstruction were recruited, 233 were analyzed.
Randomized into levobupivacaine bolus and
infusion, levobupivacaine bolus plus saline infusion,
or saline bolus with saline infusion.
Femoral nerve block performed in PACU after spinal
and deep sedation for knee surgery. Initial bolus
0.25% levobupivacaine 30ml. Infusion of 0.25%
levobupivacaine or NS at 5ml/hr until 270ml
reservoir depleted (22 hours).
2009
Retrospective analysis of prospectively collected
data from 2006.
2007 (“Rebound”)
Retrospective analysis of prospectively collected
data from 2006. Increasing nerve block duration did
not increase rebound pain (defined as [time at
which patient reported block was not providing pain
relief – recorded time of nerve block insertion on
day of surgery])
2007 (“Nausea, Vomiting, Sleep and Restfulness”)
Retrospective analysis of prospectively collected
data from 2006. QoR-40 used as measure of sleep
and restfulness. Likert-type responses were
combined into dichotomous variables for analysis.
Original Prospective Trial 2006
Patients were called to obtain NRS pain scores at
rest and with movement on POD 1-4 and 7.
Incidence of PONV determined by chart review;
criteria were administration of antiemetic or RN
documentation in PACU or Phase 2 recovery.
Results (cPNB/ssPNB)
N (cPNB) = 76
N (ssPNB) = 79
Control group = 78 (For our analysis the control
group was inapplicable).
Nerve stimulation guided block  quadriceps twitch
at 0.3-0.5mA, blinded bolus syringe administered 
catheter thread and secured  infusion device
attached.
2009
Nerve block treatment group was not significantly
associated with SF-36 or KOS-ADLS outcomes.
2007 (“Rebound”)
Block duration (hours) •: 59/37*
2007 (“Nausea, Vomiting, Sleep and Restfulness”)
% experiencing “any moderate pain” POD 1: 73/80
% experiencing “any moderate pain” POD 2: 82/83
% experiencing “any moderate pain” POD 3: 74/76
% experiencing “any moderate pain” POD 4: 64/73
% experiencing “any severe pain” POD 1: 19/31
% experiencing “any severe pain” POD 2: 26/41
% experiencing “any severe pain” POD 3: 25/36
% experiencing “any severe pain” POD 4: 27/23
2006
# PONV on day of surgery: 2/3
# needing no opioid in PACU or Phase 2 recovery:
62/61
Mg oxycodone given prior to discharge•: 11.1/10.8
Mg oxycodone consumed POD 1•: 30/33
Mg oxycodone consumed POD 2•: 25/28
Mg oxycodone consumed POD 3•: 19/20
Mg oxycodone consumed POD 4•: 14/13
Cumulative mg oxycodone used POD 1-4•: 88/94
Pain by NRS with movement POD 1†: 2/3*
Pain by NRS with movement POD 2†: 2/4*
NNTT with cPNB vs. ssPNB = 5 (to avoid 1 patient
experiencing NRS >3 w/ movement on POD 1).
NNTT with cPNB vs. ssPNB = 7 (to avoid 1 patient
experiencing NRS ≥ 5 w/ movement on POD 1).
NNTT with cPNB vs. ssPNB = 5 (to avoid 1 patient
experiencing NRS > 3 on POD 2).
NNTT with cPNB vs. ssPNB = 7 (to avoid 1 patient
experiencing NRS ≥ 5 on POD 2).
% Absolute risk reduction, NRS > 3 w/ movement on
POD 1, cPNB vs. ssPNB = 21.1*
% Absolute risk reduction, NRS ≥ 5 w/ movement on
POD 1, cPNB vs. ssPNB = 14.9*
Quality Score
(13 max.)
Notes
12
2 lost to follow-up, 5 failed routine screening, 2
cancelled by anesthesiologist, 1 patient refusal after
signup, 26 had change of surgical procedure, 1
failed to follow self-care instructions.
Prospective trial performed in 2006 with
subsequent retrospective analysis of outcomes
twice in 2007 and once in 2009.
Standardized multimodal analgesia included COX
inhibitors, ketamine, ketorolac, meperidine, and
intraarticular neostigmine.
Patients in both groups were instructed to take
oxycodone (10mg sustained release twice daily)
even if NRS pain score was 0.
Capdevila 2006
Methods
Participants
Block
Outcomes
% Absolute risk reduction, NRS > 3 w/ movement on
POD 2, cPNB vs. ssPNB = 21.2*
% Absolute risk reduction, NRS ≥ 5 w/ movement on
POD 2, cPNB vs. ssPNB = 15.4*
-1: technique (catheter placed after block
administration).
Prospective, randomized comparative trial. Neither
patient nor anesthesiologist blinded, though
assessor was blinded.
Randomization performed with a computergenerated table after successful block confirmed.
85 adult patients, ASA I-III, approached for
inclusion, two of whom had catheter malfunctions
and were excluded prior to randomization. For our
statistical analysis the basal group and the basal +
bolus group are combined.
Nerve stimulator guided interscalene for
acromioplasty or popliteal block for hallux valgus.
Blocks were performed through catheter in both
groups. 0.5% ropivacaine 30ml followed by infusion
of 0.2% ropivacaine 7ml/hr or 5ml/hr with ≤10ml/hr
PCA bolus for 72 hours. After randomization the SS
group had catheter removed in PACU and morphine
PCA started.
VAS pain scores (0-100) recorded at 1, 4, and 12
hours after arrival in PACU and every morning
during physical therapy. Physician and patient
satisfaction, morphine consumption, side effects,
and time until able to ambulate for 10 minutes were
monitored.
Study terminated early (after 23rd SS patient) when
preliminary data showed significant increase in
functional exercise capacity and reduction in VAS
scores in the continuous perineural infusion groups.
Results (c+bPNB/cPNB/ssPNB)
N (c+bPNB) = 30
N (cPNB) = 30
N (ssPNB) = 23
Continuous + bolus/ Continuous / SS
VAS w/ movement 10 min after PACU arrival†: 0/0/0
VAS w/ movement 1 hour after PACU arrival†: 0/0/0
VAS w/ movement 4 hr after PACU arrival†: 0/0/1*
VAS w/ movement 12 hr after PACU arrival†: 0/0/2.1*
VAS w/ movement POD 1†: 1/0/2.1*
VAS w/ movement POD 2†: 0/1/2.1*
VAS w/ movement POD 3†: 0/0/1.2*
Hours until able to walk for 10 min†: 12.5/20.5/40.5
Mg ketoprofen consumed in 72 hr•: 100/200/500*
% w/ free activity on day 1: 37/43/13*
% w/ free activity on day 2: 63/43/34*
% w/ free activity on day 3: 100/70/35*
% w/ assistance needed for activity day 1: 40/47/50
% w/ assistance needed for activity day 2: 31/50/66*
% w/ assistance needed for activity day 3: 0/30/65*
% with no activity on day 1: 23/10/37*
% with no activity on day 2: 6/7/0
% with no activity on day 3: 0/0/0
% with activity limited due to fatigue: 16/33/52*
Quality Score
(13 max.)
9
Notes
Six patients in PCA group, 2 patients in continuous
infusion group, and 1 patient in basal+ bolus group
had episodes of breakthrough pain and were
admitted overnight.
One patient in SS + PCA group was re-admitted for
respiratory depression after PCA pump
malfunctioned and delivered 50mg IV morphine in
12 hours.
Kean 2006
Methods
Participants
Block
Outcomes
Prospective, randomized comparative trial.
Anesthesiologist not blinded. Patient and assessor
were blinded. Randomization by anesthesiologist
writing “continuous infusion” or “single shot” on
papers in unmarked envelopes which were mixed
and numbered 1-16.
16 adult patients, ASA I-III, undergoing open
shoulder surgery.
Preoperative interscalene block with 0.5%
levobupivacaine 30ml. For continuous group
catheter was then placed and infusion of 0.25%
levobupivacaine at 5ml/hr for 24 hours. Single
injection group received sham catheter attached to
the skin with the tip of the catheter concealed by
dressing and pump attached but clamped. Surgery
performed under general anesthesia.
VAS at 6,12, and 24 hours after block (scale 0-100);
time until first additional analgesic request;
cumulative IV morphine PCA consumption; patient
satisfaction; and nausea/vomiting were recorded.
% w/ activity limited by postoperative pain:
10/23/47*
% with activity limited by paresthesia: 23/40/0*
% w/ activity limited by nausea/vomiting: 7/10/33*
% with activity limited by numbness: 16/23/0**
% with activity limited by dizziness: 10/10/33*
% with activity limited by fear of falling: 33/50/33*
% with activity limited due to other: 10/10/13
% Incidence of nausea/vomiting: 10/13/39
% Incidence of dizziness: 6/10/39
% Incidence of sleep disturbances: 3/10/22
% Incidence of pruritis: 0/7/13
% Incidence of local vein inflammation: 0/0/17
% Incidence of slight paresthesia: 17/33/9
% Incidence of numbness: 3/6/0
% Incidence of mechanical problem with IV or PNB
catheter: 17/13/39
% Patients very satisfied: 63/57/22*
% Patients satisfied: 17/23/24
% Patients mildly satisfied: 13/17/35*
% Patients not satisfied: 7/3/9
% Physicians very satisfied: 70/63/35*
% Physicians satisfied: 17/17/26
% Physicians mildly satisfied: 0/17/26*
% Physicians not satisfied: 13/3/13
-1: Allocation concealment not maintained.
-1: Technique (no true SS group).
-2: Blinding (neither patient nor anesthesiologist
blinded though assessor was blinded).
Results (cPNB/ssPNB)
N (cPNB) = 8
N (ssPNB) = 8
VAS in recovery room (scale 0-100) •: 5/10
VAS 6 hr postoperatively (scale 0-100) •: 1.25/9
VAS 12 hr postoperatively (scale 0-100) •:
0.13/26.88*
Quality Score
(13 max.)
8
Notes
When unintentional catheter dislodgement
occurred (n=1) a new patient was added to the
study.
Salinas 2006
Methods
Participants
Block
Outcomes
Quality Score
(13 max.)
Notes
Prospective, randomized comparative trial. Neither
patient nor anesthesiologist blinded, though
assessor was blinded. Randomized by computergenerated random numbers.
36 ASA I-III patients scheduled for primary total
knee arthroplasty under spinal anesthesia.
Femoral nerve block for TKA. ssPNB with 0.375%
ropivacaine 30ml through needle. cPNB with
0.375% ropivacaine 30ml through catheter followed
by 0.2% ropivacaine 10ml/hr for 36 hr.
Postoperative pain at rest and with physical therapy
(PT) assessed 4, 8, and 12 hours after block and POD
1, 2, 3; morphine and oxycodone consumption;
antiemetic requests; hospital length of stay; knee
flexion at 6 and 12 weeks postoperatively.
10
Results (cPNB/ssPNB)
N (cPNB) = 18
N (ssPNB) = 18
Initial femoral nerve block was successful in all 36
patients.
Resting VAS 4 hours after block•: 2.1/2.6
Resting VAS 8 hours after block•: 2.7/2.8
Resting VAS 12 hours after block•: 2.4/2.4
Resting VAS POD 1 (AM)•: 1.7/3.3*
Resting VAS POD 1 (PM)•: 1.7/3.8*
Resting VAS POD 2 (AM)•: 0.9/3.2*
Resting VAS POD 2 (PM)•: 1.3/3.3*
Resting VAS POD 3 (AM)•: 1.7/2.6
Peak VAS during PT POD 1•: 4.7/6.3*
Peak VAS during PT POD 2•: 3.9/6.1*
Mg morphine consumed POD 0•: 16/25*
Mg oxycodone consumed POD 1•: 15/40*
Mg oxycodone consumed POD 2•: 20/43*
Mg oxycodone consumed POD 3•: 10/26*
Cumulative mg oxycodone consumed•: 45/109*
Hospital length of stay (days) •: 3.8/3.9
Degrees of knee flexion at 6 wks•: 108/10297
Degrees of knee flexion at 12 wks•: 117/113
-1: blinding (anesthesiologist, patient, assessors not
blinded).
Multimodal analgesia included scheduled
ibuprofen.
Cuignet 2005
Methods
VAS 24 hr postoperatively (scale 0-100) •:
16.88/41.25
Mean incidence of nausea: 0.88/0.25*
Mean satisfaction (scale 0-100): 87/78*
Mg IV morphine consumed at 6 hours•: 0/0.5
Mg IV morphine consumed at 12 hours•: 0.13/3.38
Mg IV morphine consumed at 24 hours•: 3.38/27.63*
Time to first morphine requirement•: 20.03/13.39*
-2: randomization (quasi-randomization technique).
-1: technique (Single injection technique followed by
catheter placement).
-1: blinding (anesthesiologist not blinded, though
assessor and patients were blinded).
-1: intent-to-treat (accidental catheter dislodgement
not included in analysis).
Prospective, randomized, double-blind comparative
trial. Anesthesiologist, patient, and observer
blinded. Randomization of patients not described.
Preparation of randomized study solution not
described.
Results (Continuous/SS)
Participants
81 burn patients undergoing unilateral skin graft of
the thigh.
Block
Fascia iliaca compartment block under GA or spinal
prior to surgery followed by continuous infusion of
0.2% ropivacaine or NS.
1. 0.2% ropivacaine 40ml bolus followed by 0.2%
ropivacaine 10ml/hr infusion
2. 0.2% ropivacaine 40ml bolus followed by 0.9% NS
10ml/hr infusion.
3. 0.9% NS 40ml bolus followed by continuous
infusion of NS.
VAS at 6, 24, 48, and 72 hr; cumulative morphine
consumption; Bromage score (1 = no motor block, 2
= inability to lift the thigh against resistance, 3 =
inability to lift thigh against gravity, 4 = inability to
move the thigh); patient satisfaction; and side
effects were recorded.
Outcomes
Quality Score
(13 max.)
9
Notes
Authors state that lower satisfaction in continuous
nerve block group was related to motor block
causing anxiety.
Watson 2005
Methods
Participants
Block
Outcomes
Prospective, randomized comparative trial.
Anesthesiologist, patient, and observer blinded.
Randomized, by computer-generated random
numbers, and delivered in sealed envelopes.
32 adult patients, ASA I-III, with osteoarthritis
undergoing total knee arthroplasty.
Lumbar plexus block with 0.5% levobupivacaine
25ml, catheter thread in both groups. cPNB group
received 0.1% levobupivacaine at 10ml/hr while SS
group received NS 10ml/hr for 48 hours.
Single injection sciatic block performed for all
patients. Surgery under spinal and sedation.
Morphine consumption, VAS pain score at rest and
with movement, day of first ambulation, time to
meet discharge criteria, and antiemetic requirement
were recorded. Patients assessed at 4, 8, 12, 24, 36,
and 72 hours after start of surgery.
N (Ropivacaine SS + Infusion): 27
N (Ropivacaine SS + saline infusion): 27
N (Saline SS + infusion): 27
Mg IV morphine consumption in 72 hr•: 5/6
# with nausea/vomiting: 2/1
# with constipation: 3/2
# with pruritis: 17/16
# with urinary retention: 0/1
# with local anesthetic toxicity: 0/0
Bromage score•: 2/1*
Mean dynamic VAS score 6 hr postoperatively†: 1/2
Mean dynamic VAS score 24 hr postoperatively†: 1/3
Mean dynamic VAS score 48 hr postoperatively†: 2/3
Mean dynamic VAS score 72 hr postoperatively†: 2/3
Mean dynamic VAS score w/ 1st dressing change†:
3/6*
Mean static VAS score 6 hr postoperatively†: 2/2
Mean static VAS score 24 hr postoperatively†: 0/2
Mean static VAS score 48 hr postoperatively†:
0.5/1.25
Mean static VAS score 72 hr postoperatively†: 2/1.75
% patients w/ satisfaction rated “very good”: 33/48
% patients w/ satisfaction rated “poor”: 15/7
% patients w/ satisfaction rated “very poor”: 11/0
-3: randomization (technique not described).
-1 technique (block done through needle before
catheter placement).
Results (cPNB/ssPNB)
N (cPNB) = 16
N (ssPNB) = 16
Cumulative mg IV morphine†: 19/32*
# doses of antiemetic†: 0.5/0
Total nausea score†: 0.5/1
Area under static pain curve†: 55/161
Area under dynamic pain curve†: 220/318
Quality Score
(13 max.)
Notes
12
Day of first ambulation†: 2/2*
Days until discharge criteria met†: 6/6
Day of actual discharge†: 6/7
Highest VAS first night†: 3/5.5
VAS at rest 4 hr after surgery start†: 0/0
VAS at rest 8 hr after surgery start†: 0/0
VAS at rest 12 hr after surgery start†: 1/2
VAS at rest 24 hr after surgery start†: 2.5/4
VAS at rest 36 hr after surgery start†: 0/2
VAS at rest 48 hr after surgery start†: 1/0
VAS at rest 72 hr after surgery start†: 0/2
VAS w/ movement 4 hr after surgery start†: 0/0
VAS w/ movement 8 hr after surgery start†: 0/0
VAS w/ movement 12 hr after surgery start†: 2/1
VAS w/ movement 24 hr after surgery start†: 5.75/8
VAS w/ movement 36 hr after surgery start†: 4.5/5.5
VAS w/ movement 48 hr after surgery start†: 4.5/4.5
VAS w/ movement 72 hr after surgery start†: 3/4.4
-1: technique (block done through needle before
catheter placement).
Patients excluded after consent but prior to
randomization:
1- unable to locate lumbar plexus.
1- partial intravascular injection; procedure
abandoned.
1- catheter dislodged prior to surgery
All patients reported being satisfied with their
anesthetic.
Zaric 2004
Methods
Participants
Block
Outcomes
Randomization performed by central pharmacy.
Study solution prepared by pharmacy and blinding
of anesthesiologist, patient, and assessors was
maintained.
63 adult patients, ASA I-II, undergoing hallux valgus
surgery.
Surgery under spinal anesthesia with sedation.
Followed by sciatic and saphenous blocks in PACU.
Sciatic block performed with 0.5% ropivacaine 30ml,
then catheter thread and infusion at 5ml/hr of
either 0.2% ropivacaine or NS. Saphenous block
with 0.75% Ropivacaine 10ml.
VAS pain score, sleep, paresthesia, motor block,
adverse effects, satisfaction with comfort and
convenience of technique on 5 point scale (very
satisfied, satisfied, neutral, not satisfied, very
unsatisfied).
Numeric VAS extrapolated from Table (raw data not
available).
Results (cPNB/ssPNB)
N (cPNB) = 30
N (ssPNB) = 30
VAS at discharge•: 0.2/0.7
VAS 8 p.m. POD 0•: 0.3/1.6
Worst VAS POD 0•: 3.3/6.4*
VAS 9 a.m. POD 1•: 1.8/4.2*
Worst VAS POD 1•: 4.9/7.6*
VAS 8 p.m. POD 1•: 3.6/5.2*
VAS 9 a.m. POD 2•: 2.1/3.4*
Worst VAS POD 2•: 4.6/5.0
VAS 9 a.m. POD 3•: 2.5/2.0
# tablets ketomebidone consumed in 3 days†: 2/3
# with PONV POD 0†: 7/6
# with PONV POD 1†: 11/8
# with PONV POD 2†: 9/5
# patients very satisfied: 18/13
# patients satisfied: 11/14
# patients neutral: 1/2
Quality Score
(13 max.)
8
Notes
3 patients excluded from analysis due to breach of
protocol.
Ilfeld 2003
Methods
Participants
Block
Outcomes
Prospective, randomized, double-blind comparative
trial. Anesthesiologist, patient, and observer
blinded.
Randomized, by computer-generated random
numbers.
25 adult patients, ASA status unspecified,
undergoing moderately painful shoulder surgery.
Two with failed block and 2 with catheters that
could not be advanced past the needle tip. One was
admitted for social reasons and was excluded. The
remaining 20 subjects were randomized to receive
either ropivacaine (n = 10) or saline (n = 10)
infusion.
Interscalene catheter with initial 1.5% mepivacaine
40ml block followed by continuous infusion of 0.2%
ropivacaine or NS at 8ml/hr for 48 hours.
Average VAS at rest and worst VAS overall (scale 010) on POD 0, 1, 2, and 3; opioid use; satisfaction (0
= very dissatisfied,
10 = very satisfied); nausea (1 = moderate 3 =
severe); sedation (1 = drowsy, (2) dozing
intermittently, (3) mostly asleep, (4) awake only
when aroused); and pruritis (1 = only under surgical
dressings, (2) on other parts of body [minimal (2),
moderate (3), or severe (4)]).
# patients not satisfied: 0/1
# patients very unsatisfied: 0/0
# Unable to sleep on 1st nigh at home: 6/15*
Time pain-free postsurgically•: 23hr 44min/
18hr16min*
# patients requiring admission: 3/1
Min. from end of surgery to discharge•: 203.9/209.2
-3: randomization (methods not described).
-1: technique (block done through needle before
catheter placement).
-1: intent-to-treat (dropouts excluded).
Results (cPNB/ssPNB)
N (cPNB) = 10
N (ssPNB) = 10
Average VAS at rest POD 0†: 0/6*
Average VAS at rest POD 1†: 0/4.75*
Average VAS at rest POD 2†: 1.5/4*
Average VAS at rest POD 3†: 3.25/3.0
Worst VAS POD 0†: 1.5/8.0*
Worst VAS POD 1†: 3.25/8.0*
Worst VAS POD 2†: 3.5/7.0*
Worst VAS POD 3†: 7.5/7.0
Tablets oxycodone used POD 0†: 0/4*
Tablets oxycodone used POD 1†: 0.5/8*
Tablets oxycodone used POD 2†: 0/6*
Tablets oxycodone used POD 3†: 5.5/3.5
% cPNB group who used ≤1 opioid tab during
infusion: 60
% of ssPNB group receiving ≥ 4 opioid tabs by
evening of POD 0: 100*
Average patient satisfaction: 8.8/6.5*
% patients who would repeat this technique: 90/50
Nausea score POD 1†: 0/1*
Nausea score POD 2†: 0/1*
Nausea score POD 3†: 0/0
Sedation score POD 1†: 0.5/2*
Sedation score POD 2†: 0/1.5*
Sedation score POD 3†: 1.5/1
Pruritis score POD 1†: 0/1*
Pruritis score POD 2†: 1/1
Pruritis score POD 3†: 1/0.5
% with insomnia POD 1†: 30/70
Quality Score
(13 max.)
Notes
12
Multimodal analgesia included ketorolac.
White 2003
Methods
Participants
Block
Outcomes
Prospective, randomized, double-blind, comparative
trial. Randomization by computer-generated table.
Study solution prepared by pharmacy and blinding
of anesthesiologist, patient, and assessors was
maintained.
24 enrolled. Four dropouts. Adults, ASA I-III,
undergoing foot or ankle surgery (including
bunionectomy, clawtoe correction, hammertoe
correction, bone fusions or internal fixation).
0.25% bupivacaine 30ml injected through needle,
catheter then thread. Infusion of 0.25%
bupivacaine vs. NS at 5 ml/hr for 48 hours.
VRS at 1, 2, 4, 8, 24, 48, and 72 h after surgery (scale
0-10); opioid use, numbness, time to discharge, and
patient satisfaction on 0-100 scale (1 = highly
dissatisfied, 100 = highly satisfied).
Numeric VRS scores at 1hr, 2hr, 4hr, 8hr, 24hr, 48hr,
and 72hr are extrapolated from figure provided in
article.
Quality Score
(13 max.)
% with insomnia POD 2†: 30/70
% with insomnia POD 3†: 60/50
# awakenings 1st postoperative night†: 0/2*
# awakenings 2nd postoperative night†: 0/1
# awakenings 3rd postoperative night†: 0.5/1
-1: technique (block done through needle before
catheter placement).
11
Results (cPNB/ssPNB)
N (cPNB) = 10
N (ssPNB) = 10
VRS POD 0†: 2.5/7.5*
VRS POD 1†: 2/5*
VRS POD 2†: 2/4
VRS POD 3†: 2/5
VRS POD 7†: 2/2
VRS 1 hr postoperatively•: 2.65/6.8
VRS 2 hr postoperatively•: 2.1/7.1
VRS 4 hr postoperatively•: 1.7/5.45
VRS 8 hr postoperatively•: 1.25/5.9
VRS 24 hr postoperatively•: 1.5/4.75
VRS 48 hr postoperatively•: 1.5/3.7
VRS 72 hr postoperatively•: 1.8/3.1
Maximum VAS in hospital†: 4/8*
Maximum VAS after discharge†: 2.5/7.5*
Cumulative mg morphine consumed•: 10.3/34.7*
# requiring rescue analgesic in PACU: 7/10
% using rescue antiemetic drug: 10/40
% with leg weakness or numbness: 0/0
% with “tingling sensation” in foot: 80/10**
% completely satisfied w/ pain management: 90/10*
Satisfaction w/ anesthetic management•: 96/96
Satisfaction w/ pain control•: 98/77*
Satisfaction w/ quality of recovery•: 98/63*
PACU stay (min) •: 69/98
# discharged same-day: 4/0
# admitted for 23 hours: 5/6
# admitted as inpatient: 1/4
# admitted for pain control: 4/10
# admitted for social reason: 2/0
Average hospital length of stay•: 0.7/1.4*
Mcg fentanyl given for block placement•: 117/100
Mcg alfentanil given intraoperatively•: 9/21
-1: technique (block done through needle before
catheter placement).
-1: intent-to-treat (4 patients eliminated from
analysis due to catheter dislodgement prior to
discharge from hospital).
Notes
Ilfeld 2002
Methods
Participants
Block
Outcomes
Quality Score
(13 max.)
Notes
Prospective, randomized, double-blind comparative
trial. Anesthesiologist, patient, and observer
blinded. Randomized, by computer-generated
random numbers.
35 patients, ASA I-II, undergoing upper extremity
orthopedic surgery. 5 patients withdrawn from the
study due to intravascular catheter placement
(discovered at time of insertion).
Surgical infraclavicular block through needle with
1.5% mepivacaine 50ml followed by threading of
catheter and infusion of 0.2% ropivacaine or NS at 8
ml/hr with ≤6ml/hr PCA bolus for 48 hours.
Pain scores at rest and with movement (scale 0-10),
tablets of PO medication used (acetaminophen
500mg/oxycodone 5mg) and side effects, sleep
quality, patient satisfaction ((0 = very dissatisfied,
10 = very satisfied), catheter and local anesthetic
complications.
12
N (cPNB) = 15
N (ssPNB) = 15
Average VAS at rest POD 0•: 0.5/3.9*
Average VAS at rest POD 1•: 1.0/4.3*
Average VAS at rest POD 2•: 0.6/4.0*
Average VAS at rest POD 3•: 1.7/2.5
Worst VAS at rest POD 0•: 0.7/5.0*
Worst VAS at rest POD 1•: 2.9/7.1*
Worst VAS at rest POD 2•: 2.0/6.0*
Worst VAS at rest POD 3•: 3.5/3.9
Average pain with movement POD 0•: 0.6/4.7*
Average pain with movement POD 1•: 2.5/6.1*
Average pain with movement POD 2•: 1.5/5.1*
Average pain with movement POD 3•: 3.5/3.9
Worst pain with movement POD 0•: 0.9/5.5*
Worst pain with movement POD 1•: 4.5/7.9*
Worst pain with movement POD 2•: 3.7/6.8*
Worst pain with movement POD 3•: 5.3/5.8
Narcotic tabs used POD 0•: 0.3/2.5*
Narcotic tabs used POD 1•: 1.7/5.5*
Narcotic tabs used POD 2•: 1.4/5.3*
Narcotic tabs used POD 3•: 2.8/4.6*
# with nausea POD 1: 2/8*
# with nausea POD 2: 3/6
# with nausea POD 3: 2/3
# with sedation POD 1: 5/11*
# with sedation POD 2: 6/10
# with sedation POD 3: 8/6
# with pruritis POD 1: 2/4
# with pruritis POD 2: 3/5
# with pruritis POD 3: 3/6
# difficulty sleeping due to pain POD 1: 0/9*
# difficulty sleeping due to pain POD 2: 1/6
# difficulty sleeping due to pain POD 3: 4/4
# awakenings due to pain POD 1•: 0.1/2*
# awakenings due to pain POD 2•: 0.1/1.15*
# awakenings due to pain POD 3•: 0.7/0.8
-1: technique (catheter placed after SS block).
There were no apparent complications or catheter
dislocations during the study period.
Ilfeld 2002
Methods
Results (cPNB/ssPNB)
Prospective, randomized, double-blind, comparative
trial. Randomization by computer generated table.
Results (cPNB/ssPNB)
Participants
Block
Outcomes
30 patients, ASA I-II, undergoing surgery distal to
the knee out of distribution of saphenous nerve.
Popliteal sciatic block performed through needle
with 1.5% mepivacaine 50ml, then catheter
advanced. Patients received 0.2% ropivacaine or NS
at 8ml/hr with up to 6ml/hr PCA bolus for 48 hours.
Pain scores at rest and with movement, narcotic use
and side effects, sleep quality, patient satisfaction
((0 = very dissatisfied, 10 = very satisfied), catheteror local anesthetic-related complications.
Quality Score
(13 max.)
11
Notes
1 unintentional catheter dislodgement on POD 1 in
each group. No adverse effects in either group.
Borgeat 2000
Methods
Participants
Block
Outcomes
Prospective, randomized, unblinded, comparative
trial. Randomization by computerized
randomization list.
35 patients, ASA I-II, undergoing shoulder surgery.
Interscalene block with 0.75% ropivacaine 30ml
through needle in SS group, through catheter in
cPNB group. Continuous group received 0.2%
ropivacaine 5ml/hr infusion plus up to 9-12ml/hr
bolus (depending on weight). Continuous
nicomorphine plus IV PCA nicomorphine provided
to SS group. Standardized general anesthetic for
surgery.
VAS assessed at rest 6, 12, 24, 36, and 48 hours
N (cPNB) = 15
N (ssPNB) = 15
Average VAS at rest POD 0†: 0/3*
Average VAS at rest POD 1†: 0/4*
Average VAS at rest POD 2†: 0/3*
Average VAS at rest POD 3†: 1.5/2
Worst VAS POD 0†: 0/7*
Worst VAS POD 1†: 0/7*
Worst VAS POD 2†: 1/6*
Worst VAS POD 3†: 4.5/4
Tablets oxycodone used POD 0†: 0/3*
Tablets oxycodone used POD 1†: 0/8*
Tablets oxycodone used POD 2†: 0/5*
Tablets oxycodone used POD 3†: 4/4
% using no opioids during perineural infusion: 80/7*
Average satisfaction with analgesia: 9.7/5.5*
% who would repeat analgesic technique: 100/46*
Nausea score POD 1†: 0/1*
Nausea score POD 2†: 0/0*
Nausea score POD 3†: 0/0
Sedation score POD 1†: 0/2*
Sedation score POD 2†: 0/1*
Sedation score POD 3†: 0/1.75
Pruritis score POD 1†: 0/2*
Pruritis score POD 2†: 0/1*
Pruritis score POD 3†: 0/1
% with insomnia POD 1†: 8/68*
% with insomnia POD 2†: 8/60*
% with insomnia POD 3†: 48/40*
# awakenings postoperative night 0•: 0.2/2.3*
# awakenings postoperative night 1•: 0.1/1.6*
# awakenings postoperative night 2•: 1.2/0.7
-1: anesthetic care may not have been identical
(saphenous block).
-1: technique (catheter placed after block
administration).
Results (cPNB/ssPNB)
N (cPNB) = 18
N (ssPNB) = 15
VAS at rest 6 hours after block†: 0/0
after the interscalene block.
Patient satisfaction assessed 54 hours after the
interscalene block using a visual analog score (0 =
not satisfied, 10 = entirely satisfied).
Respiratory parameters monitored: diaphragmatic
excursion as measured by ultrasound, vital capacity
(Liters), FEV1 (Liters), peak expiratory flow rate
(L/min), and pulse oximetry.
Quality Score
(13 max.)
9
Notes
Two patients were excluded from the study in the IV
nicomorphine group due to intractable vomiting
that necessitated change in pain treatment.
Klein 2000
Methods
Participants
Block
Prospective, randomized, blinded, comparative trial.
Randomization not described.
ASA I-III, undergoing open rotator cuff repair.
Initial surgical interscalene with 0.5% ropivacaine
30ml, then catheter placed in continuous group.
Ropivacaine 0.2% or NS at 10ml/hr for 24 hours.
VAS at rest 12 hours after block†: 6/30*
VAS at rest 24 hours after block†: 4.5/20*
VAS at rest 36 hours after block†: 0/14.5
VAS at rest 48 hours after block†: 0/0
# nausea/vomiting: 1/9*
# pruritis: 1/3
Patient satisfaction•: 9.7/7.5*
cm tidal excursion operative side diaphragm 20 min
after block•: 0.9/0.4
cm forced excursion operative side diaphragm 20
min after block•: 1.9/0.6
cm tidal excursion operative side diaphragm 24 hr
after block•: 1.1/1.4
cm forced excursion operative side diaphragm 24 hr
after block•: 2.6/2.8
cm tidal excursion operative side diaphragm 48 hr
after block•: 1.2/1.8
cm forced excursion operative side diaphragm 48 hr
after block•: 3/3.9
cm tidal excursion non-operative side diaphragm 20
min after block•: 2.2/2
cm forced excursion non-operative side diaphragm
20 min after block•: 4.8/4.5
cm tidal excursion non-operative side diaphragm 24
hr after block•: 2.4/1.7
cm forced excursion non-operative side diaphragm
24 hr after block•: 4.8/3.2*
cm tidal excursion non-operative side diaphragm 48
hr after block•: 2.5/1.7
cm forced excursion non-operative side diaphragm
48 hr after block•: 4.5/2.7*
Vital capacity preoperatively•: 3.7/3.8
Vital capacity 20 min after block•: 2.4/2.6
Vital capacity 24 hr after block•: 2.6/3.1
Vital capacity 48 hr after block•: 2.9/3.3
FEV1 preoperatively•: 2.9/3.0
FEV1 20 min after block•: 1.8/2.1
FEV1 24 hr after block•: 2.0/2.4
FEV1 48 hr after block•: 2.3/2.6
Peak expiratory flow rate preoperatively•: 7.0/6.7
Peak expiratory flow rate 20 min after block•: 4.6/5.1
Peak expiratory flow rate 24 hr after block•: 5.1/5.7
Peak expiratory flow rate 48 hr after block•: 5.6/6.0
-2: blinding (anesthesiologists and patients not
blinded, though assessor was blinded).
-1: allocation (group allocation not well concealed).
-1: intent-to-treat (dropouts were excluded).
Results (cPNB/ssPNB)
N (cPNB) = 22
N (ssPNB) = 18
Outcomes
VAS pain scores at 2, 4, 6, 8, 10, 12, 14, 16, 18, 20,
22, and 24 hours postoperatively; opioid
requirement; patient satisfaction (0 = dissatisfied,
10 = very satisfied).
Quality Score
(13 max.)
8
VAS 2 hours postoperatively•: 0/0
VAS 4 hours postoperatively•: 0/0.15
VAS 6 hours postoperatively•: 0.65/1.15
VAS 8 hours postoperatively•: 0.5/1.45
VAS 10 hours postoperatively•: 1.3/1.2
VAS 12 hours postoperatively•: 1/3.4*
VAS 14 hours postoperatively•: 1.2/3.2*
VAS 16 hours postoperatively•: 0.55/3.15*
VAS 18 hours postoperatively•: 0.85/2.75*
VAS 20 hours postoperatively•: 1.3/2.5*
VAS 22 hours postoperatively•: 0.8/3.2*
VAS 24 hours postoperatively•: 1.6/2.85*
Total mg postoperative morphine used•: 18/36*
% requiring no morphine in 1st 24 hr postoperatively:
54/5
Serum ropivacaine level (mcg/ml) •: 1.04/0.34**
Satisfaction with anesthesia•: 10/10
Satisfaction with analgesia•: 10/9
-3: randomization (not described).
-1: technique (catheter placed after SS block).
-1: intent-to-treat analysis (patient with catheter
removal at 6 hours due to neck pain was not
described).
Notes
Borgeat 1998
Methods
Participants
Block
Outcomes
Quality Score
Prospective, randomized, comparative trial.
Randomization according to a computerized table.
65 patients, ASA I-II, undergoing elective shoulder
arthroplasty or rotator cuff repair.
Interscalene block with 0.75 % ropivacaine 30ml
which was given through catheter for continuous
infusion group. A standardized general anesthetic
was administered. The cPNB group received
continuous 0.2% ropivacaine at 5ml/hr which ssPNB
group received continuous infusion of
nicomorphine 0.5mg/hr with PCA bolus of 2-3mg q
20 minutes.
VAS pain score at 0, 6, 12, 18, 24, 30, 36, 42, and 48
hours after interscalene block (scale 0-100),
incidence of nausea, vomiting, pruritis, or other side
effects; time of first perineural interscalene or IV
PCA bolus, motor block (defined by difficulty flexing
or extending any of the fingers 12 hours after
block); and patient satisfaction 6 hours after end of
the study (0 = not satisfied, 10 = entirely satisfied).
9
Results (cPNB/ssPNB)
N (cPNB) = 30
N (ssPNB) = 30
VAS 0 hr after block•: 0/0
VAS 6 hours after block•: 0/0
VAS 12 hours after block•: 4/24*
VAS 18 hours after block•: 14/38*
VAS 24 hours after block•: 13/47*
VAS 30 hours after block•: 10/39*
VAS 36 hours after block•: 9/30*
VAS 42 hours after block•: 7/27
VAS 48 hours after block•: 4/24*
# with nausea: 3/14*
# with vomiting: 2/8
# with pruritis: 0/8*
# with motor block: 6/4
Time of first interscalene or IV PCA bolus (min) •:
930/786
Paracetamol supplement (g) •: 2.1/3.5
Patient satisfaction•: 9.6/7.5*
-2: blinding (anesthesiologists and patients
(13 max.)
Notes
unblinded, assessor blinded).
-1: allocation (group allocation not well concealed).
-1: intent-to-treat (XXX)
5 patients excluded: 3 in cPNB group and 2 in ssPNB
group. In 2 patients in group cPNB the interscalene
catheter was prematurely dislodged, and in one
patient the IS catheter could not be placed. In
ssPNB one patient was withdrawn because of
intractable vomiting due to nicomorphine and
another asked to be withdrawn due to dizziness
every time he pushed his button.
Borgeat 1997
Methods
Participants
Block
Outcomes
Prospective, randomized, comparative trial.
Randomization by computerized randomization list.
43 patients, ASA I-II, undergoing elective shoulder
arthroplasty or rotator cuff repair. 3 dropouts.
Interscalene block performed prior to surgery.
ssPNB block performed through needle. cPNB block
performed through catheter. Initial block with 0.4%
bupivacaine 30ml. Standardized general anesthetic.
For 48 hours after surgery cPNB group received
0.15% bupivacaine at 5ml/hr while ssPNB group
received continuous IV nicomorphine at 0.5mg/hr
plus bolus of 2-3mg q 20min.
VAS pain score at 0, 6, 12, 18, 24, 30, 36, 42, and 48
hours after perineural or PCA infusion started in
recovery room (scale 0-100), incidence of nausea,
vomiting, pruritis, or other side effects; time of first
perineural interscalene or IV PCA bolus, motor block
(defined by difficulty flexing or extending any of the
fingers 12 hours after block); and patient
satisfaction 6 hours after end of the study (0 = not
satisfied, 10 = entirely satisfied).
Quality Score
(13 max.)
9
Notes
3 patients were excluded from study after
randomization:
2 in cPNB group- one unintentional catheter
dislodgement and one failed catheter placement.
1 in ssPNB group withdrawn due to vomiting
related to nicomorphine.
Hirst 1996
Methods
Prospective, comparative trial.
Participants
Thirty three patients, ASA XXX, divided into 3 groups
Results (cPNB/ssPNB)
N (cPNB) = 20
N (ssPNB) = 20
VAS 0 hr•: 0/1
VAS 6 hours•: 0/10
VAS 12 hours•: 2.5/24*
VAS 18 hours•: 12.5/31*
VAS 24 hours•: 19/32
VAS 30 hours•: 17.5/30
VAS 36 hours•: 15/20
VAS 42 hours•: 14/13
VAS 48 hours•: 11/16
# with nausea: 3/6
# with vomiting: 0/5*
# with pruritis: 0/5*
# with motor block: 7/4
Time of first interscalene or IV PCA bolus (min) •:
892/832
Paracetamol supplement (g) •: 1.2/1.8
Patient satisfaction•: 9.8/7.6*
-2: blinding (anesthesiologists and patients
unblinded. Assessor blinded).
-1: group allocation (not concealed).
-1: intent-to-treat (dropouts from both groups were
excluded).
Results (cPNB/ssPNB)
N (cPNB) = 11
N (ssPNB) = 11
Block
Outcomes
Group 1- SS femoral 3-in-1 with 0.5% bupivacaine
with epinephrine 20ml injected through needle.
Group 2- Continuous femoral 3-in-1 with 0.5%
bupivacaine 20ml injected through catheter.
Group 3- mock nerve block followed by attachment
of sham catheter flowing into reservoir (group 3
disregarded for our analysis).
Standardized general anesthetic after block.
VAS at 2, 6, 12, 18, 24, and 48 hours after surgery
(scale 0-100); pain at rest and with motion (30°
passive flexion); side effects, overall patient
satisfaction; PCA morphine requirement, and XXX.
Quality Score
(13 max.)
7
Notes
Authors report no difference between overall
satisfaction; 97% of all patients were either satisfied
or very satisfied.
VAS w/ movement 0 hr •: 52/48*
VAS w/ movement 12 hours•: 62/58
VAS w/ movement 24 hours•: 60/68
VAS w/ movement 48 hours•: 58/54
VAS w/ movement 72 hours•: 42/45
VAS at rest 0 hr •: 31/38
VAS at rest 12 hours•: 32/29
VAS at rest 24 hours•: 18/24
VAS at rest 48 hours•: 13/29
VAS at rest 72 hours•: 21/17
mg morphine PCA 0-24 hours•: 25/41
mg morphine PCA 24-48 hours•: 18/24
% with nausea 24 hours postoperatively: 36/45
% with nausea 48 hours postoperatively: 9/9
-3: randomization (methods not described).
-1: allocation (not well concealed).
-2: blinding (anesthesiologists not blinded, patients
were blinded, possible unblinding of assessors).
* = p < 0.05 favoring cPNB
**= p < 0.05 favoring ssPNB
† = median
• = mean
₊It is the opinion of the authors that catheters placed after a through-the-needle bolus of LA
may not be ideal for use in a continuous block group as data are reported as means or medians
for the group and secondary block failure rates are not reported.