Raynaud’s phenomenon (RP) is characterised by reversible episodes of vasospasm in acral areas (mainly fingers and toes) triggered by a physical or emotional stimulus1. RF is called secondary when it occurs in the context of another disease; it is sometimes present in different connective tissue diseases, such as systemic lupus erythematosus or systemic sclerosis. These patients may develop ischaemic digital ulcers, which significantly affect their prognosis. We present a series of 4 cases with RF associated with systemic sclerosis, 3 of them with ischaemic ulcers, who were treated with hyperbaric oxygen (HBO).

The 4 patients were women aged between 34 and 57 years, 2 of whom were diagnosed with limited systemic sclerosis and the other 2 with diffuse systemic sclerosis. The main clinical features are summarised in Table 1. The patients were selected after previously ruling out severe interstitial lung involvement, which could be a risk factor for pulmonary barotrauma. Of these, 3 had digital hand ulcers before starting HBO treatment (2, 3 and 6, respectively) and 3 of them were receiving treatment for RF with an endothelin inhibitor or a calcium antagonist. The hyperbaric chamber treatment in all 4 cases consisted of a total of 30 sessions performed 4 days a week. In each session the patients stayed for one hour with 100% O2 at a pressure of 2.4 atmospheres absolute. Ulcer improvement was assessed according to the degree of epithelialisation (less than 50%, greater than 50% or complete epithelialisation). Additionally, the severity of RF was measured using the Spanish version of the Raynaud’s Condition Score (RCS), a self-administered questionnaire that patients completed daily for 14 days. The RCS captures the frequency, duration, severity and impact of RF episodes2.

Three of the patients had complete epithelialisation of their digital ulcers. According to the results obtained in the RCS, all 4 patients experienced a decrease in the frequency of RF episodes and 3 of them also experienced less pain and less numbness during the episodes (Table 1). As a side effect, 2 patients experienced mild middle ear barotrauma, which required discontinuation of HBO therapy for one week, although they subsequently resumed therapy without further incident.

The treatments used in secondary RF are mainly vasodilators, including calcium antagonists, phosphodiesterase E5 inhibitors, endothelin-1 inhibitors and prostaglandins3,4. Hyperbaric oxygen therapy consists of the administration of 100% oxygen in a closed chamber at a pressure of 2–3 atmospheres absolute (the hyperbaric chamber). This therapy has been used for the treatment of ulcers of different aetiologies due to its healing, angiogenic, anti-inflammatory and antimicrobial effect5. However, there are no clinical trials that support its usefulness in the treatment of digital ulcers associated with systemic sclerosis; only case reports have been found in the literature6–8. In this series, as a novelty, the impact of HBO on RF was also evaluated, and improvement was observed in 3 of the 4 patients. HBO therapy is considered a safe treatment, with middle ear barotrauma as the most frequent adverse event. Other adverse events, such as neurological oxygen toxicity or pulmonary barotrauma, are very rare9 if patients are appropriately selected.

HBO treatment could be a therapeutic alternative in patients with secondary RF who are intolerant or refractory to conventional treatments.

None to declare.