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Roles of the Microsurgeon and Anesthesiologist in the Treatment of Neonatal Upper Extremity Arterial Thrombosis: A Case Report

Keane, Alexandra M. BA*; Santosa, Katherine B. MD*; Shahrawat, Sonia M. MD; Snyder-Warwick, Alison K. MD*

doi: 10.1213/XAA.0000000000000644
Case Reports
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We present a rare case of a newborn with spontaneous, noniatrogenic arterial thromboembolism in the right brachial artery and accompanying ischemic changes to the right upper extremity, who was successfully treated with microsurgical intervention and ultrasound-guided infraclavicular brachial plexus block with a continuous infusion of ropivacaine for 48 hours. This case report highlights the emerging role of both the microsurgeon and anesthesiologist in management of spontaneous neonatal arterial thromboembolism.

From the *Division of Plastic and Reconstructive Surgery, Department of Surgery, and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri.

Accepted for publication September 1, 2017.

Funding: This study was in part supported by the Alpha Omega Alpha (AOA) Carolyn L. Kuckein Student Research Fellowship (A.M.K.), the American Society for Reconstructive Microsurgery (ASRM) Medical Student Research Grant (A.M.K.), and the National Institutes of Health (NIH) National Institute of Neurological Disorders and Stroke (NINDS) (F32NS098561 to K.B.S.) (K08NS096232 (to A.K.S.W.). The content is solely the responsibility of the authors and does not necessarily reflect the official view of the AOA, ASRM, or NIH.

The authors declare no conflicts of interest.

Address correspondence to Alison K. Snyder-Warwick, MD, Division of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8238, St. Louis, MO 63110. Address e-mail to snydera@wustl.edu.

Arterial thromboembolism (TE) in a newborn is a rare event. While over 90% of reported cases are iatrogenic, secondary to arterial catheterization,1,2 spontaneous, noniatrogenic, idiopathic TE in the newborn is exceedingly uncommon and infrequently described in the literature. The few previous reports of TE in infants suggest avoidance of surgical intervention and advocate thrombolytic and anticoagulation therapy. We present a case of a newborn with noniatrogenic, spontaneous arterial TE in the right brachial artery and accompanying ischemic changes to the right upper extremity (RUE), who was successfully treated with microsurgical intervention to remove the thrombi and an ultrasound-guided infraclavicular brachial plexus block with a continuous infusion of ropivacaine to treat vasospasm. At 15-month follow-up, the infant’s RUE was completely healed with excellent perfusion, limited wrist extension, but excellent overall function.

Written consent was obtained from the patient’s family for the publication of this case report.

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CASE REPORT

A male neonate was born vaginally without complications to a 24-year-old, G3P0 mother at 39-6/7 weeks. Maternal and antenatal histories were unremarkable. Apgar scores were 5 and 9 at 1 and 5 minutes, respectively. At delivery, however, the neonate’s RUE was pale and cyanotic, with nonpalpable pulses distal to the elbow. Given the concern for thrombus, the infant was transferred to the neonatal intensive care unit at our institution for further evaluation. On examination on arrival at our institution, he had no palpable or dopplerable right brachial, radial, or ulnar pulses. The RUE was ischemic, mottled, and pale, without capillary refill, and cool to touch (Figure 1). His fingers were flexed, with lack of spontaneous movement below the elbow. Ultrasound revealed a completely obstructing intraarterial thrombus in the distal axillary artery; the radial and ulnar arteries could not be visualized. A transcranial ultrasound was performed and revealed no evidence of hemorrhage or infarct. Additionally, an abdominal aortic ultrasound was performed and revealed no evidence of thrombus. Vascular surgery was consulted, and anticoagulation with alteplase and heparin was initiated, with a target partial thromboplastin time of 80 seconds. Plastic surgery was consulted 7.5 hours after birth and the infant was taken emergently to the operating room for RUE revascularization. Heparin was initiated before surgery with an initial bolus and continuous infusion of 28 units/kg throughout the surgery.

Figure 1.

Figure 1.

Intraoperatively, there was an abrupt color change in the arm and in the brachial artery at the transition point of the dopplerable signal. An arteriotomy was performed at this location and revealed a yellow irregular, solid material, measuring 16 mm in length, emanating from the lumen (Figure 2). After thrombectomy and arteriotomy repair, perfusion improved with a slow wave of pink progressing distally to the hand. While performing fasciotomies, the hand again became pale and mottled leading us to perform 2 additional arteriotomies that revealed platelet thrombus proximal to the brachial artery bifurcation and another from within the midportion of the brachial artery. At the completion of the case, there was a strong dopplerable signal at the radial artery at the wrist and palmar arch. The patient remained on continuous, therapeutic, systemic heparin at a dose of 28 units/kg and was monitored carefully in the neonatal intensive care unit. Partial thromboplastin time was monitored closely, every 4 hours, with a target value of 80 seconds.

Figure 2.

Figure 2.

On day of life (DOL) 2, approximately 30 hours after the revascularization procedure, the RUE became cool, edematous, tense, and mottled. There was a palpable hematoma at the right lateral chest near the axilla. The infant was urgently taken back to the operating room, and a subcutaneous hematoma was evacuated, but the color and perfusion of the hand continued to fluctuate throughout the case. Intraoperative angiogram revealed patency of the brachial, ulnar, and radial arteries but with evidence of vasospasm. Papaverine and 4% lidocaine were applied topically to the arteries. At the end of the procedure, perfusion varied despite continued anticoagulation, likely related to vasospasm.

Due to the poor appearance and concerns for vasospasm, the anesthesia team was consulted to perform a RUE peripheral nerve block to improve perfusion by vasodilation. On DOL4, we performed an ultrasound-guided infraclavicular block on the patient in the supine position after withholding heparin for 2 hours. The patient was on continuous sedation and mechanical ventilation during the procedure. After proper sterilization of the block area and proper surgical draping, the brachial plexus at the infraclavicular level was located using the 12 MHz ultrasound probe. The probe was placed inferiorly and perpendicular to the clavicle to identify the pectoralis major and minor muscles, with the axillary artery and vein seen transversely. The brachial plexus cords, located surrounding the artery laterally, medially, and posteriorly, were identified. We then used the ultrasound probe to guide a 20-gauge Touhy needle toward the posterior cord and delivered 1 mL of 0.2% ropivacaine (0.45 mg/kg) while observing the spread of the anesthetic solution, which separates the nerve from the artery. The needle insertion point was just inferior to the clavicle, and the needle was aimed toward the posterior aspect of the axillary artery. After the initial bolus dose, a 24-gauge catheter was threaded through the Touhy needle, and a continuous infusion of 0.5 mL/h of 0.2% ropivacaine was administered for 48 hours. After catheter placement, heparin was restarted 1 hour later. Dopplerable pulses were detected hours after nerve block placement and infusion. The appearance of the RUE continued to improve after initiation of ropivacaine, with consistent palpable pulses. Because the patient achieved the vasodilatory effects of the nerve block on DOL6, or 48 hours after the catheter was placed, the decision was made to remove the catheter at this time. To remove the catheter, heparin was held 2 hours prior and restarted 2 hours after removal.

Table.

Table.

Figure 3.

Figure 3.

On discharge on DOL29, the patient was sent home on therapeutic enoxaparin dosing. During his hospital course, a battery of tests and imaging revealed no congenital heart disease, hypercoagulable state, or other significant medical problems. The patient displayed finger movement for the first time at his 2-month follow-up visit. He had no episodes of vascular compromise, and his enoxaparin was discontinued after an unremarkable complete, hematologic workup at 3 months of age. Over the course of the following 4–5 months, the patient developed significant scar contractures, resulting in the inability to fully extend the wrist and elbow. To improve his function, at 8 months of age, he underwent forearm flexor tenolysis and RUE scar contracture release with excision and transposition (Z-plasty closure) (Figure 2B, C). A complete list of the patient’s surgical procedures is listed in the Table. At 15 months of life, the patient has maintained excellent perfusion. Although he has restrictions in wrist extension, he overall has excellent RUE range of motion and function (Figure 3).

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DISCUSSION

Peripheral arterial TE in a newborn is rare and requires prompt intervention to salvage the limb and avoid necrosis and subsequent amputation. Knowledge of the coagulation system profile of the newborn can aid in determining the proper course of treatment. Neonatal blood is distinct from that of adults. In the newborn, procoagulants, such as vitamin K–dependent factors and contact factors, are <70% of adult values, whereas factors V, VII, VIII, and von Willebrand factor are >70% of adult values.3 Additionally, coagulation inhibitors such as antithrombin III, protein C, and protein S are low in the newborn.3–5 These values largely contribute to hemostasis in the newborn, but slight variations in the concentrations of these factors can predispose the newborn to thrombus or hemorrhage.3

The unique profile of a newborn’s blood contributes to the decision to intervene with nonsurgical approaches, using thrombolytic and anticoagulation therapy, and less commonly with surgical intervention. The majority of the literature recommends against surgical intervention due to the infant’s young age, small blood vessel size, and potentially unknown diagnoses related to the thrombosis.2,6 On the other hand, caution must be taken in the use of heparin or enoxaparin in a newborn, largely due to the blood profile. At the Hospital for Sick Children in Toronto, 177 pediatric patients received enoxaparin prophylactically or for treatment purposes. Of these children, 4% suffered major bleeding and 17% suffered minor bleeding.7 Although enoxaparin and heparin are determined “efficacious” and “safe” in pediatric patients, these findings warrant attention, and physicians must take caution with the use of anticoagulation and thrombolytic therapy in a newborn. Surgical intervention is conventionally taken at the point of amputation. However, in the event of severe ischemic changes or the failure of anticoagulation/thrombolytic therapy, surgery is indicated.6,8 Therefore, there is a fine balance between surgical intervention and medical therapy, based on small blood vessel site and the chance for reocclusion of the vessels. Although anticoagulation is the mainstay of treatment, significant consideration needs to be taken for the side effects of bleeding and the need for close monitoring of anticoagulation. In our case, surgical intervention was pursued given the prolonged ischemic time and reports describing early surgical intervention for successful limb salvage and restoration of function.9

We present a case in which the patient’s management was not complete without the combination of surgical intervention, anticoagulation therapy, and a brachial plexus nerve block. During the procedure on DOL2, the fluctuating appearance of the arm and the intraoperative findings were consistent with arterial spasm. Usage of local anesthetics and papaverine intraoperatively improved the vasospasm, but the fluctuating perfusion continued postoperatively. The administration of a continuous ropivacaine brachial plexus nerve block was essential for this child’s limb salvage, because it provided vasodilatory effects. We leveraged the sympathectomy-like effects of the nerve block, which not only led to venous dilation, but also prevented arterial spasm, both of which improved blood flow in our patient significantly. Additionally, the availability of ultrasound enables precise location of nerve and vascular structures to deliver local anesthetic solutions by direct visualization of needle and the local anesthetic spread.

The decision to utilize a brachial nerve plexus block in the newborn requires multiple considerations relative to systemic absorption, metabolism, excretion, and toxicity profiles. In particular, aminoamide local anesthetics are primarily metabolized by CYP450 enzymes in the liver, whereas the aminoesters are predominantly metabolized by pseudocholinesterases in the periphery. The CYP450 system and phase II enzymes are immature in the newborn, and therefore have markedly reduced metabolic capacity.10 Additionally, neonates have larger relative amounts of extracellular and total body water volumes, and the adipose tissue has an increased proportion of water.11 Therefore, more hydrophilic local anesthetics that gain access to the systemic circulation will distribute into the peripheral tissues and effectively decrease the plasma concentration.11 This effect is less pronounced with more lipophilic local anesthetics.11 Moreover, local anesthetic systemic toxicity is of great concern, because local anesthetics have the potential to damage any cell with sodium channels, most notably the neurons, cardiac myocytes, and skeletal myocytes. Toxicity due to systemic absorption of local anesthetics is a serious complication and care must be taken to avoid intravascular injection. The unique anatomic and physiologic profiles of the neonate and the local anesthetic drug profile must be carefully evaluated in the decision to utilize a peripheral nerve block in the neonate.

Our case strongly suggests consideration of a peripheral nerve block to improve tissue perfusion and prevent arterial spasm in complicated surgical cases such as this. Additionally, we reveal that microsurgical intervention can be beneficial and successful in the treatment of arterial TE in infants in select cases.

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DISCLOSURES

Name: Alexandra M. Keane, BA.

Contribution: This author helped conceive the study, and draft and revise the manuscript.

Name: Katherine B. Santosa, MD.

Contribution: This author helped conceive the study, and draft and revise the manuscript.

Name: Sonia M. Shahrawat, MD.

Contribution: This author helped conceive the study and revise the manuscript.

Name: Alison K. Snyder-Warwick, MD.

Contribution: This author helped conceive the study, and draft and revise the manuscript.

This manuscript was handled by: Raymond C. Roy, MD.

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REFERENCES

1. Andrew ME, Monagle P, deVeber G, Chan AK. Thromboembolic disease and antithrombotic therapy in newborns. Hematology Am Soc Hematol Educ Program. 2001:358374.
2. Aslam M, Guglietti D, Hansen AR. Neonatal arterial thrombosis at birth: case report and literature review. Am J Perinatol. 2008;25:347352.
3. Andrew M, Paes B, Johnston M. Development of the hemostatic system in the neonate and young infant. Am J Pediatr Hematol Oncol. 1990;12:95104.
4. Andrew M, Paes B, Milner R, et al. Development of the human coagulation system in the full-term infant. Blood. 1987;70:165172.
5. Reverdiau-Moalic P, Delahousse B, Body G, Bardos P, Leroy J, Gruel Y. Evolution of blood coagulation activators and inhibitors in the healthy human fetus. Blood. 1996;88:900906.
6. Lin PH, Dodson TF, Bush RL, et al. Surgical intervention for complications caused by femoral artery catheterization in pediatric patients. J Vasc Surg. 2001;34:10711078.
7. Dix D, Andrew M, Marzinotto V, et al. The use of low molecular weight heparin in pediatric patients: a prospective cohort study. J Pediatr. 2000;136:439445.
8. Giaquinta A, Veroux M, Virgilio C, et al. Brachial thrombosis in a premature neonate. A case report. Ann Ital Chir. 2012;83:149151.
9. Zetlitz E, Weiler-Mithoff E, Turner T. Idiopathic neonatal ischemia in the upper limb: the role of the microsurgeon. Am J Perinatol. 2008;25:513516.
10. Kearns GL, Abdel-Rahman SM, Alander SW, Blowey DL, Leeder JS, Kauffman RE. Developmental pharmacology–drug disposition, action, and therapy in infants and children. N Engl J Med. 2003;349:11571167.
11. Waldman SA, Terzic A. Pharmacology and Therapeutics: Principles to Practice. 2009. Philadelphia, PA: Saunders/Elsevier; Available at: https://www.clinicalkey.com/dura/browse/bookChapter/3-s2.0-B9781416032915X5001X. Accessed June 19, 2017.
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