Missing the Signs: Vascular Occlusion and Tissue Ischemia in Skin of Colour

Introduction

In aesthetic medicine, the timely recognition of vascular compromise and tissue ischemia is critical to preventing serious complications such as necrosis. Yet traditional assessment methods, largely developed and validated on lighter skin tones, often fall short when applied to patients with richly pigmented skin. Visual indicators such as erythema, blanching, cyanosis, and mottling may be atypical, subtle, or entirely absent, leading to delayed diagnosis, mismanagement, and poorer outcomes.

Despite the severity of complications like vascular occlusion, there remains a significant lack of published research exploring how these conditions present in darker skin types. This gap reflects a broader disparity in clinical education and aesthetic training, where lighter skin continues to dominate teaching materials, imagery, and diagnostic frameworks. As a result, practitioners may be underprepared to assess and manage complications equitably across diverse patient populations.

Addressing this issue is not only a matter of clinical competence, but also an ethical imperative. Ensuring that all patients, regardless of race or skin colour, receive safe, effective, and inclusive care demands a more representative approach to education, research, and practice in aesthetic medicine.

Understanding Skin Colour and Its Clinical Implications

Pierard (1998) defines skin colour as the perceived pigmentation resulting from the selective absorption and scattering of light from the dermis. Skin colour is shaped by anatomical and physiological factors, with four primary pigments contributing: melanin, oxygenated haemoglobin, reduced haemoglobin, and carotene. The location and density of melanin, particularly its proximity to the skin surface, play a significant role in how skin appears. Carotene imparts a yellow hue, oxygenated haemoglobin appears red, and reduced haemoglobin gives a purple-blue tone.

Pigmentation and Diagnostic Visibility

Skin pigmentation plays a critical role in how vascular compromise presents, and how easily it is recognised.

Two key classifications help frame this:

• Constitutive pigmentation refers to an individual’s baseline skin tone in areas unaltered by UV exposure, such as the inner upper arm.
• Facultative pigmentation describes skin that has darkened due to environmental factors like sun exposure. Most skin sites are considered facultative (Choe et al., 2006).

These distinctions are clinically relevant, particularly in aesthetic medicine. Facultative pigmentation may obscure early signs of vascular compromise, such as erythema or blanching, especially in patients with darker constitutive tones. This can lead to delayed recognition of ischemia or necrosis.

While it may be challenging to conduct full comparative assessments during facial aesthetic treatments, practitioners should be encouraged to perform a baseline skin assessment, both visual and tactile, prior to, during, and after treatment.

This includes:

• Comparing treated areas to non-treated areas
• Noting baseline temperature, tone, and capillary refill
• Monitoring for changes in pain, texture, or symmetry

Such proactive evaluation supports safer, more equitable care and helps mitigate the risk of missed complications in patients with richly pigmented skin.

Differentiating Purpura from Impending Necrosis

One of the most critical diagnostic challenges in aesthetic complications is distinguishing purpura from impending necrosis, especially in skin of colour.

Purpura presents as purple or red discoloration due to bleeding under the skin. It does not blanch when pressed and may result from trauma, platelet disorders, or vascular fragility.

Impending necrosis, often due to vascular occlusion, may initially mimic purpura but is typically accompanied by:

• Pain or tenderness
• Coolness to touch
• Progressive dusky grey or violaceous discoloration
• Delayed capillary refill
• Swelling or induration

In darker skin tones, these signs may not be visually prominent. Therefore, clinicians must rely on tactile assessments and patient-reported symptoms rather than visual cues alone.

Recommendations for Assessing Vascular Compromise in Skin of Colour

To improve diagnostic accuracy and patient safety, aesthetic clinicians should adopt the following strategies:

Expanded Assessment Techniques

• Palpation: Assess for temperature changes, tenderness, and swelling.
• Capillary refill: Use pressure tests to evaluate perfusion.
• Pain monitoring: Ask patients about unusual or escalating discomfort.
• Visual inspection: Look for subtle changes in hue, texture, or symmetry.

Inclusive Training and Imagery

Incorporate diverse skin tones into educational materials, case studies, and simulation tools.

Use high-resolution imagery of complications across Fitzpatrick skin types.

Emerging Technologies

Near-infrared spectroscopy (NIRS) offers a promising solution. This non-invasive imaging technique measures tissue oxygenation and blood flow using light in the 700–1000 nm range. NIRS bypasses the limitations of visual assessment by providing objective, colour-independent data. An editorial in BMJ (March 2025) highlights NIRS as a reliable tool for assessing regional tissue oxygenation in perioperative settings, with potential crossover into aesthetic safety protocols.

Conclusion

Skin colour profoundly influences clinical visibility and diagnostic accuracy in aesthetic medicine. The underrepresentation of darker skin tones in training and research perpetuates disparities in care. By expanding assessment techniques, embracing emerging technologies like NIRS, and advocating for inclusive education, clinicians can ensure safer, more equitable outcomes for all patients.