Evaluating the Efficacy of Amniotic Membrane in Treating Neonatal Extravasation

Abstract

OBJECTIVE 

Extravasation is leakage of material from a peripheral venous access into adjacent tissue, which results in tissue damage ranging from local irritation to necrosis and scar formation. Neonates are at extravasation risk with IV treatment because of their small, fragile veins and the long treatment period required. In this report, investigators assessed the efficacy of amniotic membrane (AM) as a biological dressing to heal extravasation wounds in neonates.

METHODS 

This case series includes six neonates who presented with extravasation injuries from February 2020 to April 2022. Neonates born at any gestational age diagnosed with a wound secondary to extravasation were recruited. Neonates with skin disorders and those who had stage 1 or 2 wounds were excluded. Providers covered infection- and necrosis-free wounds with AM and assessed the wounds after 48 hours. Five days after placement, providers removed and replaced the AM; they continued to replace the bandages every 5 to 7 days until healed.

RESULTS 

The average gestational age of included neonates was 33.6 weeks. Average healing time was 12.5 days (range, 10-20 days), and no adverse reactions were observed. All neonates healed completely without scar formation.

CONCLUSIONS 

This preliminary report suggests that the application of AM in treating extravasation in neonates is safe and effective. However, controlled trials with larger sample sizes are needed to evaluate this outcome and determine implications for practice.

INTRODUCTION

Almost all sick or premature neonates are exposed to many medications secondary to systematic and developmental immaturity. Oral administration of drugs is ineffective in premature neonates for several reasons, including slow gastrointestinal tract motility, variable gut flora (because of gestational age, age, and feeding status), and immature gut transporters. Moreover, some of the required medications are available only in IV forms. Consequently, IV access is the primary route of drug administration in these neonates.^1,2

The need for prolonged IV access and neonates’ small, fragile veins predisposes these patients to extravasation injury.³ Extravasation is leakage of material from a peripheral venous access into adjacent tissue that results in tissue damage.⁴ Tissue damage ranges from local irritation to necrosis and scar formation based on the properties of the extravasated material and susceptibility of the patient.⁵

Based on the severity of the injury, extravasations are classified into four stages. Stage 1 presents with pain, swelling, and erythema and is managed conservatively with cessation of drug administration. In stage 2, erythema, pain, and swelling are severe, epithelial damage is seen, and pulse may be weakened. Treatment at this stage includes IV antibiotics and nitroglycerine in cases of weakened pulse. In stage 3, ulcer formation occurs. Amniotic membrane (AM) is used as a treatment in this stage. Stage 4 is characterized by bone, muscle, or tendon exposure. Surgical debridement is performed at this stage, and AM is applied afterward.⁶

Several methods have been used to treat the complications of extravasation. However, the best management remains preventive approaches and early treatment.⁶ Treatment modalities used include hyaluronidase,⁷ saline irrigation,⁸ topical nitroglycerin 2% ointment,⁹ phentolamine,¹⁰ and subcutaneous terbutaline.¹¹

The AM is the inner layer of the placenta; it has anti-inflammatory, antifibrotic, and antimicrobial properties.¹² It induces healing by several mechanisms owing to its biological and immunologic properties. The AM produces growth factors, including transforming growth factor β (TGF-β), epidermal growth factor, fibroblast growth factors (FGFs), and platelet-derived growth factors.¹³ The AM’s mesenchymal stem cells and epithelial cells contain a variety of mediators such as epidermal growth factor, keratinocyte growth factor, basic FGF, and vascular endothelial growth factor.¹⁴ These factors mediate cell proliferation; epithelization; and inhibition of fibrosis, inflammation, and bacterial infection.¹⁵

Amniotic membrane allografts have been used as biological dressings in wound management; they are derived from donor tissue that may or may not have identical genetic material with the recipient.¹⁶ Examples of AM application in wound management include ocular AM transplantation and surgery, burn wounds, diabetic foot ulcers, and surgical incisions.^17,18 To the best of the authors’ knowledge, AM has not been used in neonatal wound management, but there are a few reports on AM use in pediatric burn injuries due to Stevens-Johnson syndrome and epidermolysis bullosa.^19–21

Because AM induces proliferation and wound healing without hazardous complications, the authors assessed the efficacy of this product in treating neonatal extravasation wounds.

METHODS

The Ethics Committee of Tehran University of Medical Science approved the research with the ethical code of IR.TUMS.MEDICINE.REC.1398.530. The project followed the ethical principles and the national norms and standards for conducting medical research in Iran.

After the authors explained all the steps of the intervention, parents provided written informed consent before study enrollment confirming their approval of the intervention, wound photography, and the possible publication of the data and images.

Study Design and Population

This prospective pilot study included six neonates treated from February 2020 until April 2022 in the Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran. A public call was given to all children’s hospitals of Tehran University of Medical Sciences through contact of nursing offices of Children’s Medical Center and mentioned hospitals. Nine patients were approached, three of whom did not participate in the study. One did not consent, and two others’ living places were remote and could not visit the hospital. Inclusion criteria were neonates born at any gestational age who were diagnosed with a stage 3 noninfectious wound due to extravasation. Those with underlying skin disorders and stage 1 and 2 wounds were excluded. In cases of infectious wounds, the infection was first resolved with antibiotics prior to AM application. Neonates with stage 4 wounds underwent debridement, and when their wounds were converted to stage 3, they were included in the study.

Amniotic Membrane Preparation

The AM was purchased from Sinacell-Iran as a commercial product. The medical record of the placenta donor is thoroughly evaluated, and a blood sample is tested by real-time polymerase chain reaction for viral infections including HIV, hepatitis viruses, and cytomegalovirus. The AM batch is produced under class-A laminar hoods under sterile conditions. Each batch is tested for cell viability, bacterial and fungal infections, mycoplasma, endotoxins, and visual integrity of the membrane. The AM is placed on a sterile supportive biomedical paper made of nitrocellulose opposing its wound-facing surface. The AM is prepared in various sizes, ranging from 2 × 2 cm to 15 × 12 cm, packed in a three-layer polyethylene package along with Dulbecco modified eagle medium and stored in a − 80 °C refrigerator. Packages are transferred to the medical center inside a cold box and can be cut with sterile scissors to obtain the needed size for the wound.

Wound Care

Upon diagnosis, standard care for extravasation was undertaken: the infusion was stopped, the extremity was elevated, and a saline-soaked gauze was placed on the injury site to draw out the vesicant.²² Because of a lack of hyaluronidase enzymes and phentolamine in the authors’ hospital setting, these conservative measures were continued for 48 to 72 hours to see whether the wound would respond to this management. Following this, a multidisciplinary team made up of a wound-expert nurse, a neonatologist, and a pediatric surgeon evaluated the wound for further treatments.^23,24 Wounds containing necrosis were debrided either by autolytic debridement using a commercial wound pad (HydroClean Plus; Hartmann Group), which rinses the wound with Ringer lactate solution and absorbs exudate, or by surgical debridement. In cases of sloughed wounds, a culture was obtained, and the patient received empirical IV antibiotics with topical mupirocin until the infection was resolved.

After removing the necrotic tissue and resolving the slough, the authors implemented AM treatment. They opened the AM pack and washed the supportive paper with sterile normal saline solution to help detach it from the AM. The AM surface facing the paper was placed on the wound, then a Vaseline gauze was placed as the second dressing on the AM. A sterile gauze was placed on the Vaseline gauze, and an elastic bandage was used to bandage the wound. After 48 hours, the authors visually evaluated the wound through the transparent AM for any unwanted events. Five days after the first bandage, the authors removed the AM and replaced it with a new sheet of AM. This process was repeated until complete wound epithelization occurred. The wound was photographed at each dressing change to document and compare the progression of healing.

Adverse Events

The authors tracked adverse events (AEs)—such as adverse skin reactions (eg, urticaria), graft-versus-host disease, keloid formation, and infection—and their severity in the month after the intervention according to the Common Terminology Criteria version 5.0 for AEs.²⁵

Outcomes and Measures

The primary outcome was time to complete epithelization. Secondary outcomes were scar formation after wound treatment, hypersensitivity, and occurrence of sepsis. These secondary outcomes are important because they can increase the hospital length of stay upon occurrence, irrespective of the primary cause of admission.

RESULTS

A total of six neonates (five male, one female) ranging in gestational age from 29 to 38 weeks were included in this case series. Table 1 summarizes the demographic characteristics of the neonates, their primary cause of hospitalization, and their nutrition regimen.

Table 1. - DEMOGRAPHIC CHARACTERISTICS

Case	Sex	Gestational Age, wk	Birth Weight, g	Primary Cause of Hospitalization	Nutrition Regimen
1	Female	29	1,200	Prematurity	Total parenteral nutrition and minimal trophic feeding
2	Male	30	1,350	Respiratory distress syndrome	Total parenteral nutrition and minimal trophic feeding
3	Male	37	2,670	Dehydration	Mother’s milk (no limit)
4	Male	38	3,800	Hypoglycemia	Mother’s milk (no limit)
5	Male	38	3,500	Posterior ureteral valve	Mother’s milk (no limit)
6	Male	38	3,000	Transposition of great arteries	Total parenteral nutrition

Wound specificities are described in Table 2. Most neonates (n = 4) required two AM applications before healing. However, one neonate required three applications, and one required four applications. These two patients had larger wound areas at 1,200 and 2,000 mm², respectively, in comparison with the wound areas of the four neonates who healed after two AM applications (range, 100-500 mm²).

Table 2. - WOUND CHARACTERISTICS

Case	Site of Injury	Wound Grade	Extravasated Liquid	Injury Extent, mm	Debridement	No. of Membrane Applications	Time to Heal, d
1	Right foot	3	Blood	40 × 50	Yes (autolytic)	4	20
2	Left foot	3	Distilled water 10%	25 × 20	Yes (surgical)	2	10
3	Left foot	3	Distilled water 10%	10 × 20	No	2	10
4	Left foot	3	Distilled water 12.5%	25 × 20	Yes (autolytic)	2	10
5	Left hand	3	Distilled water 10%	30 × 40	Yes (surgical)	3	15
6	Right hand	3	Calcium gluconate 10%	10 × 10	No	2	10

Figures 1 and 2 depict the progressive results of AM application on neonatal extravasation wounds. After 4 weeks of follow-up, no AEs were noted, and all neonates healed without scar formation (Figure 2). The average healing time was 12.5 days (range, 10-20 days) irrespective of the causative agent.

Figure 1.: AMNIOTIC MEMBRANE USE TO TREAT EXTRAVASATION WOUND ON LEFT FOOT OF NEONATEThese images are of patient 5 who required surgical debridement. The images were taken 5 days apart.

Figure 2.: AMNIOTIC MEMBRANE USE TO TREAT EXTRAVASATION WOUND ON LEFT HAND OF NEONATEThese images are of patient 5, who required surgical debridement. The last image was taken on a follow-up visit 4 weeks posttreatment.

DISCUSSION

In this case series, six neonates with wounds secondary to extravasation of different liquids were managed with AM dressings. Their wounds healed after an average of 12.5 days with no scar formation or complications. Generally, wounds with greater dimensions required more membranes and time for healing. Thus, the single most important factor predicting the number of AM treatments required for complete wound healing appears to be the extent of the injury. Looking at cases 2, 3, 4, and 6 in Tables 1 and 2, these cases varied in gestational age and nutrition regimen, but all required two membranes for complete wound healing; notably, these patients all had wound areas of 500 mm² or less. However, this observation must be further assessed in controlled trials.

Whereas extravasations in preterm neonates are due to the extended IV therapy required and fragile vessels, in term neonates, extravasations are more likely caused by the infant’s rapid and vigorous limb movements during hunger, agitation, or handling by the mother that displace the catheter and tear the vessel. In both cases, the fluid leaks into the adjacent soft tissue.

Tissue injury occurs in several ways and with different mechanisms in extravasation. Extravasated fluids are classified as either infiltrates or vesicant fluids, based on their specificities. Infiltrate fluids, such as 0.9% sodium chloride solution, exert mechanical forces on blood vessels, lymphatic drainage, and subdermal plexus. The result is occlusion of blood vessels, which causes ischemia and eventual necrosis.²⁶ The amount of accumulated fluid determines the extent of injury. Infiltrate fluids containing vasopressors, such as dopamine and dobutamine, result in necrosis by causing vasoconstriction and subsequent ischemia.²⁷ Hyperosmolar fluids such as hypertonic glucose result in cell shrinkage by shifting water from the cell to the interstitial tissue.²⁸ In contrast, the mechanism of injury in vesicant fluids includes both mechanical pressure and cell death, leading to chemical burning of the skin. Drugs with a pH out of the normal range of blood (eg, phenytoin, vancomycin) cause cell damage.²² Extravasation of total parenteral nutrition fluids or calcium gluconate causes necrosis. Extravasation injuries may not be recognized until 48 to 72 hours after the leak occurs. Because newborns cannot react to the first stages of injury, some cases are identified only when necrosis is established.²⁹

There are specific treatments for each of the aforementioned extravasation mechanisms. One option is hyaluronidase, which is most effective when administered within the first 2 hours after extravasation.³⁰ Phentolamine is the antidote to vasoactive drugs such as dopamine and dobutamine and should be administered within 12 hours after injury; neonates should be closely monitored for complications such as tachycardia and hypotension. Nitroglycerin ointment dilates veins and arteries, increases capillary blood flow, and reverses ischemia and necrosis. However, because extravasation is usually diagnosed 48 to 72 hours after occurrence when necrosis is established, these contemporary treatment options are not ideal for managing extravasation wounds.

The biological and immunologic properties of AM make it a suitable therapeutic option for wound management. Although amniotic epithelial and mesenchymal cells express human leukocyte antigen complex, their reduced expression of human leukocyte antigen classes A, B, and DR and cluster of differentiation (CD)-40-, CD-80-, and CD-86-stimulatory molecules helps limit immune responses, which is why there are no reports of immunogenic reactions from AM use.³¹ Basic FGF is a proangiogenic factor and plays an essential role in fibroblast proliferation and the formation of granulocytic tissue.³² The presence of platelet-derived growth factors and vascular endothelial growth factor in the AM suggests a proangiogenic role in the hemostasis phase of wound healing.³³ The TGF-β family is responsible for synthesizing and depositing extracellular matrix proteins and regulating and transporting fibroblasts into myofibroblasts.³⁴ Mesenchymal stem cells can inhibit TGF-β and cause overproduction of fibrosis and scarring.³⁵ Amniotic epithelial cells, by interleukin 10 (IL-10), promote the expression of T-helper 1 cells and major histocompatibility complex class II molecules. Moreover, IL-10 also increases B-cell survival, proliferation, and antibody production and has been shown to inhibit the production of anti-inflammatory cytokines such as interferon γ, IL-2, IL-3, and tumor necrosis factor α. Other anti-inflammatory agents such as IL-1 receptor antagonists and tissue metalloproteinases 1, 2, 3, and 4 inhibitors have also been found in amniotic cells.^36,37 Amniotic epithelial cells express intercellular adhesion molecule 1 by inflammatory protein cytokines such as tumor necrosis factor α and IL-1b, increasing the uptake and adhesion of leukocytes.³⁸

In addition to the immunologic basis of AM’s ability to induce epithelialization and inhibit scar formation, the use of AM on the wounds has other beneficial effects. It has an analgesic effect on wound pain and helps prevent dehydration and excessive fluid loss.³⁹

To the best of the authors’ knowledge, this case series reports the first time that AM has been used to treat extravasation in neonates. The promising outcome of 100% re-epithelialization without AEs in the six cases in the report highlights this technique as a potential method of treating extravasation in neonates. However, this study is limited by its small sample size: Because extravasation is a nursing pitfall, few cases occur. Further studies with larger sample sizes and comparative clinical trials are needed to draw firm conclusions.

CONCLUSIONS

This case series reports the successful treatment of extravasation wounds in neonates with AM applications. However, further studies with larger sample sizes and clinical trials comparing the contemporary treatments with AM application are needed for clearly defined indications for practice. Because this treatment route decreases graft requirement and can be implemented by nurses with experience in wound care, it may be particularly useful in remote neonatal ICUs.