Abstract
Introduction
Although marine envenomations are a reason for consultation in tropical emergency departments, stonefish stings are particularly feared. Immediate management focuses on pain control, whereas late management addresses cutaneous complications. This study presents a new series and compares the management of these patients and their outcomes at our center over the past 20 years.
Methods
This study presents a new series of 53 patients treated between 2016 and 2020 at the South Hospital of the University Hospital Center of Réunion following a sting attributed to the stonefish. We compared this new series with a previous series of patients treated at the same center for the same reason between 2001 and 2005.
Results
The series are comparable. Regarding early management, the use of regional anesthesia was more frequent (47 vs 3.5%). Half the patients received a strong opioid. Prescription of nonsteroidal anti-inflammatory drugs and corticosteroids persisted. Exposure to a heat source remained common. Prophylactic antibiotics were prescribed more frequently (64 vs 35%) and more uniformly with amoxicillin/clavulanate. Regarding late management, the average duration of hospitalization decreased (1.8 vs 2.6 d). Cutaneous complications were less frequent (9 vs 25%). No patient managed with regional anesthesia presented cutaneous complications.
Conclusions
The management of patients in Réunion following Scorpaenidae stings has evolved over time. Regional anesthesia has become more widespread, and the prescription of probabilistic preventive antibiotic therapy is more homogeneous. These changes are associated with a shorter hospital stay and fewer cutaneous complications.
Introduction
Although marine envenomation are a reason for consultation in tropical emergency departments (EDs), stonefish stings are particularly feared.1–3 This endemic species inhabits the warm, shallow waters of the Red Sea and the Indian and Pacific oceans. 4 In Réunion, an ichthyologic inventory published in 2004 identified 11 genera and 19 species of Scorpaenidae, with Synanceia verrucosa being the only referenced stonefish species (Figure 1). 5 Considered the most venomous fish globally, its sting causes excruciating pain. Immediate management focuses on pain control, whereas late management addresses cutaneous complications.6,7
Two Synanceia verrucosa in Réunion.
A series of patients treated at the southern site (Saint-Pierre) of the University Hospital Center (CHU) of Réunion between 2001 and 2005 after suspected stonefish stings was published in 2008 8 (Figure 2). This study aimed to describe a new series of patients treated for the same reason in the same center and to compare the early and late management of patients between these 2 series.
La Réunion localization.
Methods
Cases of suspected stonefish envenomation treated between January 1, 2016, and December 31, 2020, at the southern site of the CHU of Réunion were retrospectively collected. Data of interest were extracted from electronic medical records according to the investigators’ assessment. Data collection and use were conducted in accordance with a reference methodology, declared to the regulatory commission (Commission nationale de l'informatique et des libertés). Favorable ethical approval was also obtained (French Society of Anaesthesia, Critical Care and Perioperative Medicine; ref. IRB 00010254–2021–058).
Procedures
The inclusion criterion for cases was the mention of the term stonefish either in the reason for consultation to the ED or in the medical history. This new series (2020) describes the studied population and their early and late management. Early management was defined as care provided within 12 h of consultation in the ED. Late management was defined as care provided >12 h after the consultation. A cutaneous complication was defined as any medical consultation occurring >12 h after the initial consultation due to a new cutaneous lesion or significant modification of the initial lesion. This series was compared with our previous series (2005).
Statistics
Qualitative variables were presented as counts and percentages. Quantitative variables were presented as mean±SD. To evaluate differences between groups, a significance level of 5% (P<0.05) was defined using 2-tailed tests. Categorical variables were analyzed using Pearson's χ2 test without Yates’ correction or Fisher's exact test when theoretical counts were <5. Continuous variables were compared between the 2 independent groups using Student's t test. Statistical analyses were performed via the BiostaTGV university site and Excel, version 2407 (Microsoft Corp, Redmond, WA).
Results
During the study period, the term stonefish was mentioned in the ED reason for visit or medical history of 62 patients. In 9 of these patients, another cause of the marine envenomation ultimately was identified (eg, catfish, moray eel, and others). In total, 53 patients were suspected of being stung by a stonefish during sea bathing (Table 1). All patients presented to the ED with a painful wound. The patients were predominantly male (62%), with an average age of 31 ± 18.3 (6–67) y. The stings were mostly located on the lower limb (83%). The attending physician described edema in 45% of cases, ecchymosis in 25%, necrosis in 19%, and blisters in 4%. This series did not differ from the 2005 series except for the frequency of edema, which was less common (45 vs 74%; P<0.01).
Population and sting characteristics of the 2005 and 2020 series.
Indicates statistical significance.
Regarding the early management of patients (Table 2), pain management included heat exposure in 76% of cases, with no reported burn complications. A strong opioid was prescribed in 55% of cases. Regional anesthesia was performed in 47% of cases, including 4 children aged 7 to 12 y. Nonsteroidal anti-inflammatory drugs (NSAIDs) were prescribed in 9% of cases and corticosteroids in 8%. There was marginal symptomatic prescription of local lidocaine, ketamine, nitrous oxide–oxygen mixture, midazolam, and pregabalin. Within the first 12 h, 64% of patients received prophylactic antibiotics, and 57% were hospitalized. Of patients who received regional anesthesia, 88% were hospitalized (2 others absconded and 1 had another reason). No patient received stonefish antivenom. Several patients received tetanus prevention. One patient received no treatment in the ED. Notably, between 2016 and 2020, there was an increase in the use of regional anesthesia (32% in 2016–17 vs 58% in 2018–20) and a decrease in the prescription of strong opioids (73% vs 32% in 2018–20).
Early management of the sting.
Indicates statistical significance.
Compared with the 2005 series, regional anesthesia was more frequent (47 vs 4%; P<0.01), and prophylactic antibiotics were prescribed more frequently (64 vs 35%; P<0.01). Notably, the prescribed antibiotic therapy was more homogeneous, with amoxicillin/clavulanate prescribed more frequently (97 vs 74%; P=0.02). There was no significant difference in hospitalization rates between the 2 series (P=0.25).
Regarding the late management of patients (Table 3), a medical consultation for a new cutaneous lesion >12 h after the initial consultation in the ED occurred in 9% of cases. Among them, 2 patients developed extensive or painful edema, 2 developed erysipelas, and 1 developed necrotizing fasciitis requiring surgical debridement. No abscesses were observed in our series. Among the 3 patients with infectious cutaneous complications, 1 had received NSAIDs without amoxicillin/clavulanate, another had received amoxicillin/clavulanate without corticosteroids or NSAIDs, and the last with necrotizing fasciitis had received corticosteroids and amoxicillin/clavulanate. None of the 5 patients had been managed with regional anesthesia.
Later management of the sting.
indicates statistical significance.
No patient was treated in our hyperbaric chamber. Twenty-three percent of patients received preventive thromboprophylaxis with home blood pressure monitoring. The average length of stay was 1.8±0.9 d. The longest hospitalization lasted 5 d. No patient reconsulted for the envenomation within a period exceeding 3 mo. No organ failure or deaths were observed.
Compared with the 2005 series, there were fewer cutaneous complications (9 vs 25%; P=0.04). The 2005 series reported progression of the initial sting to necrotizing fasciitis in 4 cases and an abscess in 1 case. The duration of hospitalization was significantly shorter (1.8 vs 2.6 d; P<0.01).
Discussion
This is a new series of 53 patients treated after marine envenomation suspected to be caused by a stonefish. The demographic and semiologic characteristics were comparable with other published series.9–11 The treated wounds were similar between our 2 series, with mostly lower limb lesions and regularly described associations with ecchymosis or necrosis. Notably, edema was less frequently described in this series, which we attribute to less reporting due to a documentation bias, given the commonality of this sign in this context, or the involvement of different providers. The authors of the 2005 series highlighted the need for a more standardized analgesic strategy and the prescription of prophylactic antibiotics. In 2015, a sequential analgesic protocol was implemented in our southern hospital, with first-line prescription of usual analgesics and/or a thermal shock, followed by regional anesthesia if necessary. Although its efficacy is not demonstrated, thermal shock with a hot water soak remains widely used in our center. The continued use of this option in our protocol and practices reflects the benefit attributed to it by teams regularly exposed to this envenomation.
The use of regional anesthesia has increased significantly, in line with recent trends in the literature on the treatment of pain from marine envenomations.11,12 However, the prescription of strong opioids remained frequent between our series. We believe that their ease of administration and rapid action meet a strong demand for immediate analgesia—unless the trend between 2016 and 2020 of progressively increasing the use of regional anesthesia and the parallel decrease in the prescription of strong opioids indicates the gradual implementation of our protocol with a shift from morphine to regional anesthesia.
We observed a more frequent and systematic early prescription of antibiotic therapy with amoxicillin/clavulanate. Although there are no specific recommendations from the French Infectious Diseases Society for the management of wounds after marine envenomation, prophylactic antibiotics with amoxicillin/clavulanate are recommended after a traumatic wound, especially when the wound is a small orifice with a deep, penetrating mechanism and difficult to access for effective cleaning. 13 Although the bacterial ecology is rich and specific, the use of a broad-spectrum beta-lactam such as amoxicillin/clavulanate is regularly proposed and appears suitable for a systematic infection-prevention strategy following marine envenomations. 1
We observed that the use of NSAIDs and corticosteroids remains minor but persistent, although it is recommended not to prescribe them in the management of common bacterial skin infections. 14 Imaging is not required by our protocol, but the persistence of a foreign body in 9% of cases in a recent Australian series invites reconsideration of this choice. 11 Note that our center does not have an antivenom serum.
We observed a trend toward more frequent hospitalization. The explanation is clear: Our protocol requires that the performance of regional anesthesia be followed by hospitalization for monitoring. The implementation of an ambulatory pathway should reduce the hospitalization rate of these patients in the future.
Regarding the evolution of patients in our series, despite the trend toward more frequent hospitalization and equally frequent prescription of thromboprophylaxis, the average length of stay decreased between the 2 series. The explanation may be given by the significantly lower proportion of reported cutaneous complications—unless, despite a generally shorter hospitalization duration, the hospitalizations in this series allowed for the prevention of several complications. This decrease in cutaneous complications probably explains the disappearance of the need for hyperbaric medicine.
It is sometimes difficult to distinguish between extensive painful edema and erysipelas, so we do not interpret the trend toward a decrease in noninfectious cutaneous complications. However, we found interesting the observed trend toward a decrease in the number of necrotizing fasciitis cases (1 vs 4). These results support the increased frequency of prophylactic antibiotics use with amoxicillin/clavulanate. The cutaneous infectious evolution was not prevented in 2 cases despite the prescription of antibiotic therapy, whereas no patient managed with regional anesthesia evolved toward a cutaneous infectious complication. The authors of a Polynesian series proposed the hypothesis of a preventive cutaneous action of regional anesthesia through its vasodilatory effect. 9
This study has several limitations, including those inherent to retrospective studies, such as potential biases in data collection and the reliance on accurate and complete medical records. Cutaneous complications were not evaluated by a dermatologist, which could introduce bias in the classification of observed lesions. Several pieces of information would have been valuable, such as knowledge of any medical consultation prior to the ED visit or following hospital discharge. The duration of antibiotic therapy is not specified. The timing and modalities of regional anesthesia are not detailed. Late management includes events occurring more than 12 h after the initial consultation in the ED as well as those occurring several days later. A follow-up evaluation of patients would have been beneficial.
Primarily, this series does not rely on any visual or biological confirmation of the species involved. The certainty of the origin of the sting is challenging in marine envenomation, and no clinical criterion is pathognomonic of a stonefish sting. The inclusion in our series of a patient who received no treatment indicates possible classification errors. Series describing patients after suspected stonefish stings face the same diagnostic challenges and also have selected their patients based on anamnestic criteria.10,11,15,16
It is important to note that severe stings from Scorpaenidae can manifest as intense pain and cutaneous lesions of the extremities, such as edema, erythema, or necrosis. 1 This family includes numerous species, some of which are highly camouflaged, such as various species of scorpionfish, lionfish, leaf scorpionfish, or stonefish. Although patient selection is based on the mention of the species stonefish, it would be more appropriate to classify these patients more generally as victims of Scorpaenidae stings. Nevertheless, the classification of these patients with typical anamnestic features by clinicians from an experienced center, the specific ability of the stonefish among Scorpaenidae to remain immobile, and the frequent need for regional anesthesia support the suspicion of a stonefish sting for the patients in this series. Ultimately, this study provides insights into the evolution of the management and outcomes of patients treated after suspected marine envenomation by a stonefish during sea bathing in an endemic area within a center experienced in this type of care.
Conclusions
The management of patients in Réunion following suspected stonefish envenomation has evolved over time. Probabilistic preventive antibiotic therapy with amoxicillin/clavulanate has been prescribed more frequently and systematically. The use of regional anesthesia for pain control has become widespread. Immersion in hot water soaks remains common. These changes are associated with shorter hospital stays and fewer cutaneous complications. No patient managed with regional anesthesia developed cutaneous complications.
Footnotes
Acknowledgments
The authors thank Agathe and Célestin Renson and Nicolas Bouscaren for their help and Samir Medjane for his guidance. Figure 1 - Photo credit: Elisabeth Morcel, CC BY-SA 3.0, via Wikimedia Commons. License available at:
Author Contribution(s)
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
Formal Presentation
Presented as a poster orally at the annual meeting of the French Society of Anaesthesia and Intensive Care, September 23, 2021, Paris, France.