Use of ultrasound guidance to remove entrapped stimulating popliteal catheters Russell K. McAllister, MD, James B. Hulin, DO, and Don J. Daniels, MD
Peripheral nerve catheters are beneficial for continuous pain relief following surgery or trauma to an extremity. However, spring-loaded peripheral nerve catheters can become uncoiled and entrapped, resulting in difficulty in catheter removal. We present two cases where ultrasound guidance provided significant assistance in the safe removal of entrapped peripheral nerve catheters without neurologic sequelae. One of the catheters was adhered to nearby tissue, and one had become uncoiled and anchored in place by the distal tip. Guidelines for the safe management of entrapped catheters are suggested, including the use of saline injections through the catheter under ultrasound guidance to assist in the evaluation and removal of the catheters. Figure 1. Distal tip configuration of Arrow StimuCath.
P
eripheral nerve catheters are typically easily removed when the need for nerve blockade has ended. However, spring-loaded peripheral nerve catheters are at risk for uncoiling with entrapment of the catheter and wire in nearby structures. We report two cases of entrapped catheters following popliteal nerve block utilizing a 20-gauge catheter (Arrow StimuCath, Teleflex Medical Germany, Kernen, Germany) with a coiled omni-port end with a hemispherical distal tip (Figure 1). Identification and removal of the catheters was facilitated by the use of ultrasound. We report on the assessment and management of entrapped continuous peripheral nerve catheters. CASE 1 A 24-year-old American Society of Anesthesiologists class I woman underwent a left tibiotalar arthrodesis under general anesthesia. The plan for postoperative analgesia included the placement of a continuous popliteal nerve block. In the postanesthesia care unit, a continuous popliteal catheter was placed utilizing a lateral approach and ultrasound guidance. A 17-gauge insulated needle was used to place a 19-gauge 60 cm StimuCath continuous nerve block catheter after obtaining nerve stimulation with dorsiflexion at 0.55 milliamperes. The catheter was secured with tape and attached to an elastomeric pump prior to discharging the patient home. On postoperative day 3, the patient was unable to remove the catheter and presented for further evaluation. She denied any radicular pain. The catheter insertion site was clean and dry, and the Proc (Bayl Univ Med Cent) 2016;29(2):147–149
patient had a normal lower extremity neurologic examination. An attempt to withdraw the catheter under ultrasound visualization demonstrated lateral movement of the common peroneal and tibial nerves. Injection of 10 mL of preservativefree normal saline through the catheter failed to relieve the apparent adhesion. Lateral and anteroposterior x-rays of the knee did not reveal a knot or kinking of the catheter (Figure 2). A second attempt of injecting 20 mL of saline through the catheter under ultrasound guidance successfully loosened the catheter, resulting in its easy removal. CASE 2 A 28-year-old man sustained a traumatic injury to his right foot, requiring multiple surgeries including external fixation and washouts. Ultimately, the patient underwent a transmetatarsal amputation and opted for a continuous popliteal nerve block for postoperative analgesia. In the preoperative holding area, a popliteal nerve block was placed utilizing a posterior approach and ultrasound guidance. A From Baylor Scott & White Health and Texas A&M College of Medicine, Temple, Texas (McAllister, Daniels); and Integris Southwest Hospital, Oklahoma City, Oklahoma (Hulin). Corresponding author: Russell K. McAllister, MD, Assistant Dean, Quality and Patient Safety and Residency Program Director, Department of Anesthesiology, Baylor Scott & White Health, 2401 S. 31st Street, Temple, TX 76508 (e-mail: [email protected]). 147
Figure 2. Lateral knee radiograph revealing no obvious kinking or knotting of the catheter.
17-gauge insulated needle was used to place a 19-gauge 60 cm StimuCath continuous nerve block catheter after obtaining nerve stimulation with dorsiflexion at 0.50 milliamperes. The catheter was secured and connected to an elastomeric pump prior to discharge. On postoperative day 5, the patient was unable to remove the catheter and returned for further evaluation. The catheter site was clean and dry with minimal erythema, and the right lower extremity neurologic exam revealed no deficits in sensory or motor function. Ultrasound examination of the popliteal fossa did not reveal movement of the neurovascular structures when traction was placed on the catheter. However, traction on the catheter did produce tenting under the skin at the location of the distal tip of the catheter. This area was prepped and draped in sterile fashion, and the skin was anesthetized with 3 mL of 1% lidocaine. Blunt dissection exposed the metallic tip of the catheter, which was acting as an anchor. Traction on the catheter had produced uncoiling of the distal end. The hemispherical tip was cut from the end of the catheter and removed through the incision site. Once the anchoring tip was removed, the remaining portion of the catheter was easily removed through the initial insertion site (Figure 3).
Figure 3. StimuCath catheter following removal in two parts reveals the uncoiled distal end. 148
DISCUSSION Complications from peripheral nerve catheters are rare but important (1–3). These two cases demonstrate potential problems that may be encountered when using the Arrow StimuCath system. Both cases resulted in entrapped peripheral nerve catheters. Wiesmann et al reported two similar cases of entrapped stimulating catheters (4). In one of the cases, when the catheter was unable to be removed with forceful traction, a surgical removal was planned under general anesthesia. Once muscle relaxation occurred, additional forceful traction on the catheter allowed it to be removed intact without neurologic sequelae. In the second case, additional force was used and the catheter was removed intact. In both cases, the coiled ends of each catheter had become uncoiled, as described in our patients. To aid in the removal of entrapped peripheral nerve catheters, we recommend the following approach: • Prior to attempting to remove the catheter, ensure full sensation has returned to the limb. • Use ultrasound to identify the neurovascular bundle. If traction on the catheter produces displacement of the neurovascular structures, withhold traction. • Inject preservative-free normal saline through the catheter (hydrodissection) to loosen adhesions and reattempt removal of the catheter under ultrasound visualization. • Inject contrast media through the catheter to rule out catheter kinking or coiling. • Contact a surgeon for evaluation and possible surgical removal. The proposed mechanism for catheter entrapment in the first case was adhesions. Buckenmaier et al found that the manufactured design of a continuous peripheral nerve block tip can contribute to adhesions in a rat model (5). They postulated that removal of an adhered catheter could potentially cause neural damage or injury to adjacent structures, including blood vessels. The proposed mechanism of entrapment in the second case was uncoiling of the spring-wound distal tip. Damage to the spring-wound catheter tip during placement, most commonly by shearing forces if the catheter is withdrawn back into the needle, may increase the risk of uncoiling during removal, resulting in damage to nearby structures. Ultrasound was used to evaluate the neurovascular bundle and revealed no evidence of movement of the nerve complex when traction was placed on the catheter. However, skin tenting by the uncoiled wire catheter tip was noted within the tunnel site when traction on the catheter was released. We propose that ultrasound evaluation may offer advantages over plain x-ray in management of entrapped catheters. Ultrasound allows visualization of the neurovascular structures, whereas x-rays do not. In addition, the stimulating catheters with the coil tips are visible with ultrasound, allowing identification of catheter tip location. Most importantly, ultrasound visualization of these structures and their relationship to the catheter tip during gentle traction and “hydrodissection” is not only diagnostic, but in some cases may be therapeutic in relieving adhesions. A similar technique has also been used to facilitate removal of a knotted femoral nerve catheter that had become
Baylor University Medical Center Proceedings
Volume 29, Number 2
entrapped, theoretically by expanding the area just below the fascia iliaca with 10 mL of saline. This increased area allowed for easy removal of the knotted catheter (6). In addition, the portability and simplicity of most ultrasound machines allows for additional flexibility. Ultrasound evaluation would also offer a more feasible solution in patients with an allergy to intravenous contrast agents. There have been no case reports to date revealing damage to neurovascular structures upon removal of a continuous peripheral nerve catheter. However, the potential exists for damage, and further study of the diagnosis and management of these types of problems would be beneficial. 1.
Borgeat A, Blumenthal S, Lambert M, Theodorou P, Vienne P. The feasibility and complications of the continuous popliteal nerve block: a 1001-case survey. Anesth Analg 2006;103(1):229–233.
April 2016
2.
3.
4.
5.
6.
De Tran QH, De La Cuadra-Fontaine JC, Chan SY, Kovarik G, Asenjo JF, Finlayson R. Coiling of stimulating perineural catheters. Anesthesiology 2007;106(1):189–190. Cuvillon P, Ripart J, Lalourcey L, Veyrat E, L’Hermite J, Boisson C, Thouabtia E, Jacques Eledjam J. The continuous femoral nerve block catheter for postoperative analgesia: bacterial colonization, infectious rate and adverse effects. Anesth Analg 2001;93(4):1045–1049. Wiesmann T, Wallot P, Nentwig L, Beermann AV, Wulf H, Zoremba M, Al-Dahna T, Eschbach D, Steinfeldt T. Separation of stimulating catheters for continuous peripheral regional anesthesia during their removal—two case reports and a critical appraisal of the use of steel-coil containing stimulating catheters. Local Reg Anesth 2015;8 15–19. Buckenmaier CCIII, Auton AA, Flournoy WS. Continuous peripheral nerve block catheter tip adhesion in a rat model. Acta Anaesthesiol Scand 2006;50(6):694–698. Kendall MC, Nader A, Maniker RB, McCarthy RJ. Removal of a knotted stimulating femoral nerve catheter using a saline bolus injection. Local Reg Anesth 2010;3 31–34.
Use of ultrasound guidance to remove entrapped stimulating popliteal catheters
149
Peripheral nerve catheters are beneficial for continuous pain relief following surgery or trauma to an extremity. However, spring-loaded peripheral nerve catheters can become uncoiled and entrapped, resulting in difficulty in catheter removal. We present two cases where ultrasound guidance provided significant assistance in the safe removal of entrapped peripheral nerve catheters without neurologic sequelae. One of the catheters was adhered to nearby tissue, and one had become uncoiled and anchored in place by the distal tip. Guidelines for the safe management of entrapped catheters are suggested, including the use of saline injections through the catheter under ultrasound guidance to assist in the evaluation and removal of the catheters. Figure 1. Distal tip configuration of Arrow StimuCath.
P
eripheral nerve catheters are typically easily removed when the need for nerve blockade has ended. However, spring-loaded peripheral nerve catheters are at risk for uncoiling with entrapment of the catheter and wire in nearby structures. We report two cases of entrapped catheters following popliteal nerve block utilizing a 20-gauge catheter (Arrow StimuCath, Teleflex Medical Germany, Kernen, Germany) with a coiled omni-port end with a hemispherical distal tip (Figure 1). Identification and removal of the catheters was facilitated by the use of ultrasound. We report on the assessment and management of entrapped continuous peripheral nerve catheters. CASE 1 A 24-year-old American Society of Anesthesiologists class I woman underwent a left tibiotalar arthrodesis under general anesthesia. The plan for postoperative analgesia included the placement of a continuous popliteal nerve block. In the postanesthesia care unit, a continuous popliteal catheter was placed utilizing a lateral approach and ultrasound guidance. A 17-gauge insulated needle was used to place a 19-gauge 60 cm StimuCath continuous nerve block catheter after obtaining nerve stimulation with dorsiflexion at 0.55 milliamperes. The catheter was secured with tape and attached to an elastomeric pump prior to discharging the patient home. On postoperative day 3, the patient was unable to remove the catheter and presented for further evaluation. She denied any radicular pain. The catheter insertion site was clean and dry, and the Proc (Bayl Univ Med Cent) 2016;29(2):147–149
patient had a normal lower extremity neurologic examination. An attempt to withdraw the catheter under ultrasound visualization demonstrated lateral movement of the common peroneal and tibial nerves. Injection of 10 mL of preservativefree normal saline through the catheter failed to relieve the apparent adhesion. Lateral and anteroposterior x-rays of the knee did not reveal a knot or kinking of the catheter (Figure 2). A second attempt of injecting 20 mL of saline through the catheter under ultrasound guidance successfully loosened the catheter, resulting in its easy removal. CASE 2 A 28-year-old man sustained a traumatic injury to his right foot, requiring multiple surgeries including external fixation and washouts. Ultimately, the patient underwent a transmetatarsal amputation and opted for a continuous popliteal nerve block for postoperative analgesia. In the preoperative holding area, a popliteal nerve block was placed utilizing a posterior approach and ultrasound guidance. A From Baylor Scott & White Health and Texas A&M College of Medicine, Temple, Texas (McAllister, Daniels); and Integris Southwest Hospital, Oklahoma City, Oklahoma (Hulin). Corresponding author: Russell K. McAllister, MD, Assistant Dean, Quality and Patient Safety and Residency Program Director, Department of Anesthesiology, Baylor Scott & White Health, 2401 S. 31st Street, Temple, TX 76508 (e-mail: [email protected]). 147
Figure 2. Lateral knee radiograph revealing no obvious kinking or knotting of the catheter.
17-gauge insulated needle was used to place a 19-gauge 60 cm StimuCath continuous nerve block catheter after obtaining nerve stimulation with dorsiflexion at 0.50 milliamperes. The catheter was secured and connected to an elastomeric pump prior to discharge. On postoperative day 5, the patient was unable to remove the catheter and returned for further evaluation. The catheter site was clean and dry with minimal erythema, and the right lower extremity neurologic exam revealed no deficits in sensory or motor function. Ultrasound examination of the popliteal fossa did not reveal movement of the neurovascular structures when traction was placed on the catheter. However, traction on the catheter did produce tenting under the skin at the location of the distal tip of the catheter. This area was prepped and draped in sterile fashion, and the skin was anesthetized with 3 mL of 1% lidocaine. Blunt dissection exposed the metallic tip of the catheter, which was acting as an anchor. Traction on the catheter had produced uncoiling of the distal end. The hemispherical tip was cut from the end of the catheter and removed through the incision site. Once the anchoring tip was removed, the remaining portion of the catheter was easily removed through the initial insertion site (Figure 3).
Figure 3. StimuCath catheter following removal in two parts reveals the uncoiled distal end. 148
DISCUSSION Complications from peripheral nerve catheters are rare but important (1–3). These two cases demonstrate potential problems that may be encountered when using the Arrow StimuCath system. Both cases resulted in entrapped peripheral nerve catheters. Wiesmann et al reported two similar cases of entrapped stimulating catheters (4). In one of the cases, when the catheter was unable to be removed with forceful traction, a surgical removal was planned under general anesthesia. Once muscle relaxation occurred, additional forceful traction on the catheter allowed it to be removed intact without neurologic sequelae. In the second case, additional force was used and the catheter was removed intact. In both cases, the coiled ends of each catheter had become uncoiled, as described in our patients. To aid in the removal of entrapped peripheral nerve catheters, we recommend the following approach: • Prior to attempting to remove the catheter, ensure full sensation has returned to the limb. • Use ultrasound to identify the neurovascular bundle. If traction on the catheter produces displacement of the neurovascular structures, withhold traction. • Inject preservative-free normal saline through the catheter (hydrodissection) to loosen adhesions and reattempt removal of the catheter under ultrasound visualization. • Inject contrast media through the catheter to rule out catheter kinking or coiling. • Contact a surgeon for evaluation and possible surgical removal. The proposed mechanism for catheter entrapment in the first case was adhesions. Buckenmaier et al found that the manufactured design of a continuous peripheral nerve block tip can contribute to adhesions in a rat model (5). They postulated that removal of an adhered catheter could potentially cause neural damage or injury to adjacent structures, including blood vessels. The proposed mechanism of entrapment in the second case was uncoiling of the spring-wound distal tip. Damage to the spring-wound catheter tip during placement, most commonly by shearing forces if the catheter is withdrawn back into the needle, may increase the risk of uncoiling during removal, resulting in damage to nearby structures. Ultrasound was used to evaluate the neurovascular bundle and revealed no evidence of movement of the nerve complex when traction was placed on the catheter. However, skin tenting by the uncoiled wire catheter tip was noted within the tunnel site when traction on the catheter was released. We propose that ultrasound evaluation may offer advantages over plain x-ray in management of entrapped catheters. Ultrasound allows visualization of the neurovascular structures, whereas x-rays do not. In addition, the stimulating catheters with the coil tips are visible with ultrasound, allowing identification of catheter tip location. Most importantly, ultrasound visualization of these structures and their relationship to the catheter tip during gentle traction and “hydrodissection” is not only diagnostic, but in some cases may be therapeutic in relieving adhesions. A similar technique has also been used to facilitate removal of a knotted femoral nerve catheter that had become
Baylor University Medical Center Proceedings
Volume 29, Number 2
entrapped, theoretically by expanding the area just below the fascia iliaca with 10 mL of saline. This increased area allowed for easy removal of the knotted catheter (6). In addition, the portability and simplicity of most ultrasound machines allows for additional flexibility. Ultrasound evaluation would also offer a more feasible solution in patients with an allergy to intravenous contrast agents. There have been no case reports to date revealing damage to neurovascular structures upon removal of a continuous peripheral nerve catheter. However, the potential exists for damage, and further study of the diagnosis and management of these types of problems would be beneficial. 1.
Borgeat A, Blumenthal S, Lambert M, Theodorou P, Vienne P. The feasibility and complications of the continuous popliteal nerve block: a 1001-case survey. Anesth Analg 2006;103(1):229–233.
April 2016
2.
3.
4.
5.
6.
De Tran QH, De La Cuadra-Fontaine JC, Chan SY, Kovarik G, Asenjo JF, Finlayson R. Coiling of stimulating perineural catheters. Anesthesiology 2007;106(1):189–190. Cuvillon P, Ripart J, Lalourcey L, Veyrat E, L’Hermite J, Boisson C, Thouabtia E, Jacques Eledjam J. The continuous femoral nerve block catheter for postoperative analgesia: bacterial colonization, infectious rate and adverse effects. Anesth Analg 2001;93(4):1045–1049. Wiesmann T, Wallot P, Nentwig L, Beermann AV, Wulf H, Zoremba M, Al-Dahna T, Eschbach D, Steinfeldt T. Separation of stimulating catheters for continuous peripheral regional anesthesia during their removal—two case reports and a critical appraisal of the use of steel-coil containing stimulating catheters. Local Reg Anesth 2015;8 15–19. Buckenmaier CCIII, Auton AA, Flournoy WS. Continuous peripheral nerve block catheter tip adhesion in a rat model. Acta Anaesthesiol Scand 2006;50(6):694–698. Kendall MC, Nader A, Maniker RB, McCarthy RJ. Removal of a knotted stimulating femoral nerve catheter using a saline bolus injection. Local Reg Anesth 2010;3 31–34.
Use of ultrasound guidance to remove entrapped stimulating popliteal catheters
149
