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Responding to Challenges in Modern Combat Casualty Care: Innovative Use of Advanced Regional Anesthesia

Alexander Stojadinovic MD, Alyson Auton BA, George E. Peoples MD, Geselle M. McKnight CRNA, Cynthia Shields MD, Scott M. Croll MD, Lisa L. Bleckner MD, James Winkley MD, Mary E. Maniscalco-Theberge MD, Chester C. Buckenmaier III MD
DOI: http://dx.doi.org/10.1111/j.1526-4637.2006.00171.x 330-338 First published online: 1 July 2006

ABSTRACT

Background. The war in Iraq has resulted in a high incidence of severe extremity injury requiring multiple surgical procedures and extensive rehabilitation. We describe the use of advanced regional anesthesia to meet this significant medical challenge.

Methods. From March 2003 to December 2004, 4,100 casualties have been evacuated to Walter Reed Army Medical Center (WRAMC). Of 1,400 inpatients, 750 have been battle-injured with 500 having extremity injuries. Of these, 287 (57%) received surgical care incorporating regional anesthesia including single-injection peripheral nerve blocks and continuous peripheral and epidural infusion catheters. Wounding, surgical, anesthetic, and outcomes data have been prospectively collected.

Results. Over 900 operations (mean 4 ± 2/patient) were performed on 287 casualties prior to arrival at WRAMC, and 634 operations (mean 2 ± 1/patient) were performed at WRAMC. Thirty-five percent of this cohort was amputees. In the study group, 646 advanced regional anesthesia procedures, including 361 continuous peripheral nerve blocks (CPNBs), were performed with a mean catheter infusion time of 9 days (1–34). Catheter-related complications occurred in 11.9% of casualties and were technical or minor in nature. Catheter-related infection rate was 1.9%. In 126 casualties with indwelling CPNB catheters, a significant decrease in pain score over 7 days was apparent (mean 3.7 ± 0.2 to 2.2 ± 0.2, P < 0.001).

Conclusion. Advanced regional anesthetic techniques allowed for safe perioperative surgical anesthesia and analgesia in the management of the modern combat casualty.

  • Combat
  • Wound
  • Regional Anesthesia
  • Peripheral Nerve Block
  • Continuous Peripheral Nerve Block

Introduction

Despite the increasing lethality of modern weaponry, combat mortality (killed in action to wounded in action ratio) has declined steadily since World War II [1–3]. Over this period, the mechanism and anatomical distribution of injury has changed with multiple complex wounding patterns predominating [1,2,4]. Recent improvements in protective body armor account for the reduced incidence, severity, and mortality of penetrating trauma to the thorax and abdomen. However, the combined effects of blast, penetrating fragment, and burns from improvised explosive devices contribute to a high incidence of multiple penetrating wounds to the extremities with extensive soft tissue and bone destruction [5]. The increased severity and complexity of these often survivable war wounds pose formidable surgical treatment challenges and mirror the experience of the victims of suicide bombings worldwide [6–8].

Improved methods of providing surgical anesthesia, perioperative analgesia, and effective pain control during evacuation and rehabilitation are essential in modern combat casualty care. Regional block anesthesia with long-acting anesthetics has proven safe and effective for a broad range of elective orthopedic procedures and has qualities uniquely suited to the treatment of modern-day war casualties [9–12]. Although the technology is not new, continuous catheter-based peripheral nerve blocks have experienced a resurgence in use for the care of extremity operations, perioperative analgesia, and rehabilitation. Regional anesthesia provides superior pain control to opioid-based anesthesia [11,13]. Our combat wounded population is unique. The severity of wounds results in pain management challenges that preclude the use of narcotics as the sole pain modality because of side-effects with excessive use. The principal aim of this study is to demonstrate the safety of advanced regional anesthesia in meeting the anesthetic and pain management challenges of treating the multiply injured soldier.

Materials and Methods

This is a retrospective analysis of patient care data collected prospectively. The study was approved by the Walter Reed Army Medical Center (WRAMC) Institutional Review Board. From March 2003 through December 2004, 287 casualties were treated at the WRAMC regional anesthesia/acute pain section utilizing both single injection and continuous (catheter-based with portable pump delivery systems, Cadd Prism Pump, SIMS Deltec, Inc, Saint Paul, MN, USA) peripheral nerve blocks (advanced regional anesthesia), in addition to standard multimodal perioperative pain management (nonsteroidal anti-inflammatory medications, narcotic analgesics, benzodiazepines, gabapentin). Patient demographic information, clinical pain score, regional anesthetic complications, and outcome data were entered and maintained in the Army Regional Anesthesia Combat Casualty Database (ARACCD), developed as part of the Army Regional Anesthesia & Pain Management Initiative (ARA&PMI). The information collected was obtained from prospective electronic clinical records. All information in the clinical record was collected prospectively but entered into the database retrospectively. For this analysis, the database was queried for soldier demographics, injury location, nature and extent of wounds, surgical interventions, regional anesthetic treatments, catheter complications, and pain scores.

Patient follow-up was defined from time of admission to WRAMC to last interaction between patient and member of the ARA&PMI team. Severity of pain was evaluated with a 10-point verbal analog pain scale (VAS) score: 0 = no pain, 10 = worst pain imaginable. All pain scores were obtained by hospital nurses as part of routine record keeping and not by regional anesthesia team members or researchers.

As the majority of casualties had more than one operation, for the purpose of this analysis, pain scores were collected from the time of first preoperative peripheral nerve catheter placement to the time of next operation or seventh postoperative day, whichever came first. Pain data were obtained by averaging the patient's pain scores throughout each day of this arbitrary time period. These scores were collected in the setting of multimodal analgesia. Each patient in this study received a combination of nonsteroidal anti-inflammatory and narcotic analgesics, benzodiazepines, and gabapentin. Complete VAS data were obtained for 126 casualties with continuous regional infusion catheters. Patient data were stored in the ARACCD using FileMakerPro 7.0 (FileMaker Inc., Santa Clara, CA, USA).

Statistical Analysis

Summary statistics were obtained using established methods and tabulated. The dependent variable of interest was change in overall pain score (VAS) from baseline. Differences in observed pain score means were evaluated utilizing analysis of covariance with repeated measures according to the general linear model. Statistical analysis was carried out using MINITAB14 statistical software package (Minitab Inc., State College, PA, USA). For the analysis, P < 0.05 was considered statistically significant.

Results

As of February 2005, there were 6,656 army soldiers among the 10,372 service members wounded during deployments to a combat zone. Of the 6,000 soldiers who were evacuated from Iraq or Afghanistan, approximately two thirds (4,100 wounded) were cared for at WRAMC with 1,400 undergoing inpatient treatments. Of the 750 cases directly attributable to battle injury, approximately 66% (∼500) involved traumatic extremity injury. Two hundred and eighty-seven of these 500 combat casualties received surgical treatment at WRAMC that incorporated advanced regional anesthetic techniques (both peripheral nerve blocks and continuous peripheral and epidural infusion catheters) to treat severe extremity injuries.

In our cohort of 287 battle-injured, predominantly male soldiers, the most common mechanism of wounding was blast or fragment (Table 1). Generally, war wounds were multiple (mean 3 ± 1 [range = 1–10] wounds/person) and most frequently involved osseous and soft tissue disruption of the extremities. Many casualties with orthopedic trauma suffered multiple bone, ligament, nerve, and/or tendon injuries. Over 50% of patients treated in this study had greater than one orthopedic injury (148/287). Approximately 12% of the casualties underwent major vascular repair (33/287).

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Table 1

Demographic and injury-related characteristics of combat casualties treated with regional anesthetic blocks (N = 287)

CategoryN% of TotalMean ± SEM
Gender
  Male26993.7
  Female 18 6.3
Age (years)28 ± 6 (18–58)
  18–20 3311.5
  21–3016858.5
  31+ 8630.0
Injury mechanism
  Blast or fragment16858.5
  Bullet 3913.6
  Motor vehicle accident 16 5.6
  Crush 10 3.5
  Blunt  3 1.0
  Unknown 5117.8
Injury category
Single site, nonorthopedic  7 2.4
  Head/neck  1
  Thoracic  2
  Soft tissue  4
Single site, one-orthopedic10034.8
  Major vascular repair  4
Multisite (>1)—no orthopedic  1 0.3
Multisite (>1)—single orthopedic 3110.8
  Major vascular repair  9
Multisite (>1)—multiple (>1) orthopedic 5117.8
  Major vascular repair 11
Multiple (>1) orthopedic only 9733.8
  Major vascular repair  9
Amputation*10737.30 ± 1 (0–3)/person
Amputation type
  Finger/toe 1310.7
  Hand/foot/ankle  9 7.4
  Above elbow 1512.4
  Below elbow 1411.6
  Hip disarticulation  2 1.7
  Above knee 3226.4
  Through knee  1 0.8
  Below knee 3528.9
  • * A total of 121 amputations (114 traumatic, 7 post-traumatic) among 107 casualties.

In this patient subset of 287 severely injured wartime casualties, 37.3% suffered traumatic amputations (107 casualties with 121 amputations) predominantly involving the lower extremities (62.8%). Thirteen of 107 (12.1%) amputees had multiple (≥2) amputations. Nearly 70% (107/154) of amputees treated at WRAMC underwent advanced regional anesthesia for the purpose of surgical anesthesia and/or perioperative analgesia.

WRAMC was the fifth in the chain of evacuation extending from the battalion aid station and/or forward surgical team, to the combat support hospital in Iraq, the general hospital in Germany, and then to Washington, DC. Over 900 operations were conducted on these casualties along the chain of evacuation prior to arrival in the United States (Table 2A). Casualties underwent multiple operations in the field (Iraq, Afghanistan, or Germany, mean 4 ± 2 [range = 0–14]) operations/person) aimed principally at damage control or surgical stabilization that included amputation, external fixation and fracture stabilization, wound debridement, washout, packing and/or vacuum-assisted closure, fasciotomy, and hemorrhage control. Operations involving the head and neck, thorax, or abdominal cavity were relatively infrequent in our patient population.

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Table 2A

Distribution of 931 operations in 287 combat casualties according to anatomic site or trauma category conducted prior to transfer to WRAMC

OrthopedicN = 290OtherN = 32Abdominal explorationN = 23
Traumatic amputations114Retrograde urethrogram 1Negative5
External fixation104Urethral reconstruction1Diverting colostomy2
Antibiotic beads placement 10Orchiopexy1Splenectomy2
ORIF, IM nail, or rod 39Orchiectomy1Pelvic hematoma2
Joint exploration/arthroscopy 13Proctoscopy2
Nerve or tendon repair 9Head and neckN = 32Esophogram/esophagoscopy2
Bone graft1Suture facial/scalp lacerations6Bowel injury repair1
Neck exploration5Diaphragm repair1
Soft tissueN = 249Globe repair5Decompressive laparotomy1
Wound debridement/VACTracheostomy4Renal pelvis repair1
  Single 92Eye enucleation3Liver laceration1
  Multiple (≥2)127ORIF—mandible3Cholecystectomy1
STSG or flap coverage 7Tarsorrhapy2Gastrostomy tube1
Burn wound care 9Frontal craniectomy, coverage1Diagnostic peritoneal lavage1
Foreign body removal14Repair scleral laceration1
Canthotomy, cantholysis1Unknown—undocumentedN = 19
VascularN = 66Canthus medialization1
Major arterial repair 32
Fasciotomy 34ThoracicN = 24
Arteriogram 6Tube thoracostomy14
Thrombectomy 3Pericardial window3
Revision of anastomosis 3Bronchoscopy3
Inferior vena cava filter 2Wedge resection of lung2
Groin exploration 1Stabilization of flail chest1
Hematoma evacuation 1Sternotomy, hemorrhage control1

The 287 combat casualties underwent 634 operations under advanced regional anesthesia during their hospitalization at WRAMC. Primary indication for regional anesthesia was operation (N = 580), pain control (N = 40), and operation + pain control (N = 14). Combat casualties required multiple operations (mean 2 ± 1 [range = 1–9] operations/patient) during prolonged hospital stays at WRAMC (mean 25 ± 15 [2–148] days). These operations were largely definitive in nature (Table 2B) following multiple debridements, including pulse lavage and vacuum-assisted closure, which minimized the risk of infection common to war wounds.

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Table 2B

Distribution of 634 operations conducted at WRAMC by sequential surgical intervention in 287 combat casualties

#1 (N = 287)#2 (N = 176)#3 (N = 77)#4 (N = 35)#5 (N = 24)
AmputationAmputationAmputationAmputationAmputation revision
Amputation revisionAmputation revisionAmputation revisionAmputation revisionArthrotomy
ArthroplastyArthroplastyExtremity ex-fixArterial repairHardware removal
ArthroscopyArthroscopyJoint reconstructionExtremity ex-fixJoint fusion
Bone graftingBone rod or nailingORIF—extremityHardware removalScar release
Bone rod or nailingExtremity ex-fixScar releaseORIF—extremityWound flap, STSG
Extremity ex-fixHardware removalWound closureTendon repair/transferWound I&D, VAC
Hardware removalJoint reconstructionWound flap, STSGWound flap, STSG
Joint fusionLigament repairWound I&D, VACWound I&D, VAC
Joint reconstructionNerve repair
Ligament repairNeurolysis
Nerve repairORIF—extremity
NeurolysisTendon repair/transfer
ORIF—extremityWound closure
Scar releaseWound flap, STSG
Tendon repair/transferWound I&D, VAC
Tenolysis
VATS
Wound closure
Wound flap, STSG
Wound I&D, VAC
#6 (N = 15)#7 (N = 11)#8 (N = 6)#9 (N = 3)
Amputation revisionAmputation revisionAmputation revisionAmputation revision
ArthrotomyHardware removalORIF—extremityWound I&D, VAC
Hardware removalWound flap, STSGWound closure
Wound flap, STSGWound I&D, VACWound I&D, VAC
Wound I&D, VAC
  • ORIF = open reduction, internal fixation; VAC = vacuum-assisted closure; STSG = split thickness skin graft; ex-fix = external fixation; VATS = video-assisted thoracic surgery; I&D = incision, drainage (and/or debridement).

Utilization of regional anesthetic single-injection blocks (N = 285) and indwelling continuous peripheral nerve block (CPNB) catheters (N = 361), amounting to over 1,700 catheter days (mean 2 ± 1 blocks and 1 ± 1 catheters/patient), facilitated frequent returns to the operating room and control of pain during rehabilitation (Table 3A). Many blocks for operation were established through previously placed catheters. Single-injection blocks and continuous peripheral nerve catheters are enumerated in Table 3B.

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Table 3A

Summary of regional anesthetic blocks or catheters in 287 patients

BlocksContinuous CatheterEpidural CatheterTotal
Single Injection≥2 Single InjectionSingle InjectionContinuous CatheterBlock × 2BolusBolus ≥1
Initial block and/or catheter54462572760N/A14287
Subsequent blocks and/or catheter4130 84328N/A45 2197
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Table 3B

Type of 646 advanced regional anesthetic blocks in 287 combat casualties

Regional Single-Injection BlocksRegional Continuous Catheters
Regional BlockNRegional BlockN
Axillary  1Posterior cervical  1
Femoral 30Femoral  9
Infraclavicular 46Infraclavicular 24
Intercostal-brachial 12Interscalene 10
Interscalene  7Lumbar epidural 16
Lumbar plexus 70Lumbar plexus110
Paravertebral thoracic  1Paravertebral thoracic  4
Popliteal  4Popliteal  2
Saphenous  7Sciatic133
Sciatic 78Supraclavicular 52
Supraclavicular 29
Total single-injection blocks285Total catheters361

Median patient follow-up time was 25 days. Of 361 continuous nonstimulating anesthetic infusion catheters, technical malfunction (placement failure or occlusion) was evident in 2.2% of cases (Table 4). Catheter-specific complications were infrequent (6.6%). All seven catheter-site infections (rate of 1.9%) were superficial skin infections that resolved with catheter removal. Unplanned catheter removal was noted in 37 (10.2%) cases, most commonly in response to patient request (N = 15: adequate analgesia without catheter infusion [N = 6], inadequate pain control [N = 3], local pain at catheter entry site [N = 2], disconcerting extremity paraesthesias [N = 2], or paresis [N = 2][Table 4]).

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Table 4

Catheter-related mechanical problems, morbidity, and basis for nonroutine removal (N = 361 catheters)

Catheter MalfunctionN (% of total catheters)Catheter/Block ComplicationsN (% of total catheters)Reason for Catheter RemovalN (% of total catheters)
Placement failed—aborted3 (0.9)Arterial puncture—self-limited 2 (0.6)Dislodged inadvertently 6 (1.7)
Placement failed—single-injection success3 (0.9)Catheter-site infection—superficial 7 (1.9)Catheter-site infection— superficial 7 (1.9)
Occlusion—replaced1 (0.3)Sympathectomy 1 (0.3)Adequate pain control after infusion discontinued 1 (0.3)
Occlusion—removed1 (0.3)Bedside removal failed—success under fluoroscopy 1 (0.3)Catheter occlusion 2 (0.6)
Multiple attempts to establish successful block 2 (0.6)Catheter-site leak 1 (0.3)
Intended block failed—alternate route successful10 (2.8)Primary service request* 5 (1.4)
Tachycardia with test dose— otherwise stable. Second test dose uneventful 1 (0.3)Patient request15 (4.2)
Total8 (2.2)24 (6.6)37 (10.2)
  • * Primary service request was based on transfer elsewhere, adequate pain relief with patient-controlled analgesia (PCA), and fever without local complications.

Complete VAS pain scale data were available for 126 casualties possessing indwelling continuous regional infusion catheters. Mean pain score prior to regional catheter placement in these 126 casualties was 3.7 ± 0.2 (range = 0–8). Mean pain score from the time of first preoperative peripheral nerve catheter placement to the time of next operation or seventh postoperative day, whichever came first, was calculated. Mean pain score recorded daily over this period of time was 2.2 ± 0.2 (range = 0–6). While the primary indication for advanced regional anesthesia was operation, a significant reduction in severity of pain was evident over the course of follow-up (P < 0.001).

Discussion

The principal mechanism of injury in the present war in Iraq is the improvised explosive device, which accounts for the characteristic complex and multidimensional wounding patterns confronted by combat surgeons [5]. Extremities are the most frequent anatomic sites of injury. Severe and complex extremity trauma requires difficult and innovative treatment approaches, often requiring multiple operations and a prolonged recovery.

General anesthesia is a common anesthetic technique used in the surgical care of battle casualties, and opioid medications are the mainstay of acute perioperative pain management [13]. Concern over adverse side-effects from both general anesthesia and narcotic analgesia, as well as continued pain during evacuation and resuscitation despite prehospital morphine administration, has prompted renewed interest in regional anesthesia. Regional anesthetic techniques are not new to combat casualty care, however. Thompson reported the use, utility, and safety of primarily single-injection, short-acting peripheral nerve blocks in the surgical care of 494 of 1,000 battle casualties treated in an army surgical hospital during the Vietnam War [14].

CPNBs have been utilized for various outpatient operations and offer important advantages over general anesthesia. Benefits include prolonged pain control with fewer side-effects, reduced surgical stress response and perioperative blood loss, and more rapid functional postoperative recovery [15–19]. Given the change in battlefield wounding patterns, requirement for multiple operations, and necessity for improved pain control, CPNB may be a well-suited addition to the care of modern-day war casualties. The preponderance of continuous catheter use by our institution in managing amputees speaks to the advantages of using this technology in these difficult patient care cases. Limited logistical resources in remote areas, the challenges of managing mass casualties, and the typically extended and painful casualty evacuation flights engender the call for more effective pain management beyond that of morphine administration alone. Morphine has been the stand-alone de facto drug relied on for the management of acute traumatic pain for almost 200 years. Modern technological advances can now support substantially more effective pain control far forward on today's battlefield—control unattainable in previous conflicts.

The principal aim of this report was to define the safety of advanced regional anesthesia in the treatment of combat casualties and to provide baseline data on which to evaluate the feasibility of applying these techniques in conjunction with standard multimodal pain management approaches. WRAMC has considerable experience in the tertiary care of the multiply injured soldier, and in our practice, regional anesthetic techniques have supported frequent returns to the operating room, provided durable perioperative analgesia, and facilitated patient recovery and rehabilitation through improved pain control.

Technical failure or malfunction and catheter-specific complications were infrequent in this study and compare favorably with recently published data (Table 5). Nearly 10% of hospitalized casualties arriving at WRAMC are blood culture-positive for Acinetobacter baumanii, raising obvious concern for catheter-related infection. Prophylactic antibiotics were frequently administered in high-risk patients and may have influenced the low infection rate (1.9%) identified in this study. All catheter-site infections were superficial and resolved with catheter removal and antimicrobial treatment. In addition to its minimal side-effects, portable infusion pump technology allowed injury site-specific local anesthetic delivery and significant long-lasting analgesia in conjunction with standard multimodal pain management. Although the catheter-related morbidity was low, the relatively short median follow-up time (25 days) may have contributed to some, expectedly few, complications having gone unrecorded.

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Table 5

Comparison of catheter-related complications in the literature [21–25]

ReferenceNInfectionPositive Catheter CultureVascular PunctureSensory Block FailurePain at Insertion SiteNeuro Symptom Not ToxicityCatheter Insertion FailedDifficult Catheter InsertionCatheter Removal Technical Problems/ inadequate AnalgesiaCatheter Removal Accidental or DisconnectCatheter LeakCatheter MigrationCatheter Kinked or OccludedRetained CatheterLocal Anesthetic ToxicityTypes of Regional Catheter
Cuvillon et al. 2113 (1.4%)120 (57%)12 (5.6%)17 (8.0%)9 (4.2%)1 (0.5%)3 (1.4%)20 (9.5%)NR3 (1.4%)NRNR3 (1.4%)NR0 (0%)Femoral
Bergman et al. 4051 (0.25%)1 (0.25%)NRNRNR4 (1.0%)NRNR31 (7.7%)NRNRNRNR1 (0.25%)2 (0.5%)Axillary
Horlocker et al.4,2980 (0%)NRNRNRNR0 (0%)NRNR634 (14.8%)*223 (5.2%)79 (1.8%)104 (2.4%)111 (2.6%)1 (0.02%)0 (0%)Lumbar Epidural
Capdevila et al.1,4163%278/969 (28.7%)41 (2.9%)12/374 (3.2%)NR93 (6.6%)6 (0.4%)80 (5.6%)253 (17.9%)10.5%NRNRNRNR1 (0.07%)CPNB
Current study 3617 (1.9%)NR2 (0.6%)2 (0.6%)2 (0.6%)5 (1.7%)6 (1.8%)12 (3.4%)6 (1.7%)6 (1.7%)1 (0.3%)0 (0%)2 (0.6%)0 (0%)0 (0%)See Table 3B
  • * Represents sum of catheter dislodgement, occlusion, disconnection, leakage, migration, and inadequate analgesia.

  • Represents sum of technical problems with catheters and devices (kinked catheter, catheter withdrawn inadvertently, displaced catheter, blocked catheter, leakage of the local anesthetic around the catheter, unwanted stopping of the electric pump, alarms for no reason, and others).

  • N = number of catheters; NR = not reviewed; CPNB = continuous peripheral nerve block.

This preliminary descriptive report has limitations that deserve comment. Although advanced regional anesthetic techniques can be applied safely and effectively to combat casualties, this report did not compare these techniques to more traditional pain care therapy, and as such they cannot be regarded as superior to standard perioperative anesthesia and pain management approaches. The study population is highly selected (casualties with severe extremity wounds and often multiple and complex injury patterns requiring frequent return to the operating room) as evidenced by the striking discrepancy in rate of amputation in the present analysis compared with the war-wounded population as a whole (35% vs 2%, respectively).

An endpoint of interest, pain control, was not the principal focus of the present analysis, and was not studied in a controlled manner. We elected to direct the analysis to patients with catheters, as CPNB infusion techniques are presently under evaluation for their implementation close to the point of wounding on the battlefield in the combat support hospital. The difficulty in collecting complete pain data outside of a controlled trial is evident in the fact that comprehensive pain information is available and presented in under half of the study patients. In conjunction with the regional blocks, the battle-wounded in this series were also treated with varying types of adjuvant analgesics. The observed lower mean baseline pain scores may be attributable to the use of these multimodal pain regimens. The VAS score recorded was an average daily calculation reflecting patient responses at various times and conditions of the day. The authors believe that CPNB may have contributed to lower mean overall pain scores than would have otherwise been observed in this population had they received only standard pain management.

We have witnessed a medical cultural bias in essence dictating that war wounds are necessarily painful and that pain management is primarily reactive in nature [20]. However, the ongoing wars have brought about a strategic change in the care of the battle wounded. In response to the elevated demands for narcotic analgesics in combat casualties, a strategy of multimodal, proactive pain management has emerged. This strategy critically examines the practicality of advanced regional anesthesia applied close to the point of wounding. Although this groundwork study supports the safety of continuous catheter regional anesthesia for combat casualty care in a tertiary referral center, it remains to be determined whether it can be implemented successfully in our battlefield combat support hospitals. In fact, we recently began utilizing CPNB soon after an injury in the combat zone [21]. While it is premature to analyze outcome data at this point, no infection or local anesthetic toxicity has been observed thus far in over 50 battlefield catheters placed and remaining in situ for a period ranging from 2 to 17 days.

The value and efficacy of this approach would be addressed definitively in a prospective randomized trial comparing casualties having continuous catheter-based peripheral nerve blocks with those with standard perioperative anesthesia and pain management (no catheter group). Given the setting in which this trial would have to be conducted, the combat zone, and the evacuation chain, such a study would not be possible. Therefore, prospectively collected data to support observational studies will be the basis on which decisions to implement advanced regional anesthetic techniques in the care of the combat wounded are made.

Some concerns remain regarding the implementation of these techniques (e.g., the effect continuous peripheral nerve infusions may have on the ability to diagnose early compartment syndrome; the potential for local anesthetic toxicity and catheter site infection; and the loss of protective reflexes in the blocked extremity). Thus far these concerns remain unsubstantiated. Neurological outcome data for prolonged use of advanced regional anesthesia in the care of combat casualties are currently being collected in order to better define the role of injury site-specific, long-acting local anesthetic delivery in this setting. A number of issues and practical challenges are currently being addressed as advanced regional anesthetic techniques, once utilized only by specialized civilian medical centers, are applied to the battlefield. With the recent implementation of advanced regional anesthesia on the modern battlefield, excellent surgical anesthesia and perioperative analgesia, stable hemodynamics, and improved recovery are but a few of the advantages we have identified in our experience that warrant further study.

The current wars in Iraq and Afghanistan have posed many challenges to the military medical system but few have been as significant as the severely injured extremity. The use of advanced regional anesthetic techniques has allowed for the effective management of these complex injuries. Our preliminary experience indicates that these techniques are safe. Although not the aim of this study, our personal experience seems to suggest that advanced regional anesthetic techniques are effective and provide improved pain control, facilitating frequent returns to the operating room and postoperative recovery. Advanced regional anesthetic techniques have been applied to 70% of our combat amputees and appear to be an effective way of contributing to early rehabilitation. The modern casualty of war calls upon a multidisciplinary intensive team approach to assuage the suffering caused by numerous, often disfiguring, wounds and to restore functional capacity. We are indebted to our men and women in uniform for their sacrifices.

Footnotes

  • The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Department of the Army or the Department of Defense.

References

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