Conflict of Interest Declaration

The ILCOR Continuous Evidence Evaluation process is guided by a rigorous ILCOR Conflict of Interest policy. The following Task Force members and other authors were recused from the discussion as they declared a conflict of interest: none applicable

The following Task Force members and other authors declared an intellectual conflict of interest and this was acknowledged and managed by the Task Force Chairs and Conflict of Interest committees: none applicable

CoSTR Citation

Pek JN, Swee Lim S, Charlton NP, Ong G, Welsford M, Singletary EM, Douma MJ, Carlson JN, Djarv T, on behalf of the International Liaison Committee on Resuscitation (ILCOR First Aid Task Force) Available from: http://ilcor.org

Methodological Preamble (and Link to Published Systematic Review if applicable)

The continuous evidence evaluation process for the production of Consensus on Science with Treatment Recommendations (CoSTR) started with a systematic review of first aid interventions for the treatment of jellyfish stings which was performed by Michelle Welsford with members of the Cochrane Review Group, in conjunction with a Task Force systematic review of the first aid treatment of jellyfish stings.

In 2023, the Cochrane Library, with participation by an ILCOR systematic reviewer (MW), published an updated systematic review on the interventions for treatment of jellyfish stings {McGee 2023}. This review identified 15 articles that were evaluated for full text eligibility. Of these 15 articles, only two new articles met inclusion criteria {DeClerck 2016 25; Isbister 2017 258} to add to the seven prior studies included in the original 2013 Cochrane systematic review on the treatment of jellyfish stings {Li 2013}. A total of nine studies (six RCTs and three quasi‐RCTs) with a total of 574 participants {Bowra 2002 A22; DeClerck 2016 25; Isbister 2017 258; Loten 2006 329; McCullagh 2012 560; Nomura 2002 624; Thomas 2001 100; Thomas 2001 205; Turner 1980 300} were included in this updated Cochrane review. In the Cochrane systematic review interventions were characterized into hot or cold treatments, topical treatments and parenteral treatments. The overall evidence for all outcomes was of very low certainty. The data suggest that heat may reduce pain when compared to cold following stings from Physalia [pain at 6 hours (risk ratio (RR) 2.25, 95% confidence interval (CI) 1.42 to 3.56; at 1 hour RR 2.66, 95% CI 1.71 to 4.15; at the end of treatment RR 1.63, 95% CI 0.81 to 3.27). However, heat may not reduce pain for the jellyfish Carybdea alata and Chironex fleckeri (pain at 1 hour RR 1.16, 95% CI 0.71 to 1.89; pain at 6 hours RR 1.66, 95% CI 0.56 to 4.94; pain at the end of treatment RR 3.54, 95% CI 0.82 to 15.31). Regarding topical applications, treatment with seawater, fresh water, Sting Aid, Adolph's ® meat tenderizer, isopropyl alcohol, heated water, acetic acid, lidocaine, or sodium bicarbonate resulted in no significant difference in overall improvement between the different treatments. However, in one study ammonia treatment of the jellyfish sting resulted in a first‐degree burn in one participant. The author’s concluded that due to the very low certainty of evidence they were unsure of the effectiveness of any of the treatments evaluated in the review.

This TFSR aimed to identify additional information to aid in the formulation of treatment recommendations. A systematic review of the literature was conducted to identify additional evidence in the literature for the treatment of adult and pediatric jellyfish stings. Heat and cold as well as topical chemical treatments were evaluated. Evidence from this review incorporated randomized and non-randomized trials which were not included in the Cochrane review, whereas the Cochrane review evaluated only randomized trials. The First Aid Task Force did not include the parenteral treatments, contrary to the Cochrane review, as it was felt that parenteral treatments were outside the scope of a first aid provider. All data were considered when formulating the Treatment Recommendations.

PICOST

The PICOST (Population, Intervention, Comparator, Outcome, Study Designs and Timeframe)

Population: Adults and children with a suspected jellyfish sting

Intervention: Any pain reducing or harm minimizing technique (or combination of techniques) appropriate for first aid, such as vinegar, sea water, topical anesthetics, meat tenderizer, cold packs, urine, wet sand rubs, aloe, other commercial topical products (i.e., Sting No More), or pressure bandaging with immobilization.

Comparators: Heat or cold treatment in any form appropriate for first aid (hot/cold water, hot rocks, hot packs, cold packs) or no treatment

Outcomes:

• ● Pain reduction (yes/no or amount)

• ● Time to pain reduction

• ● Survival

• ● Need for hospitalization

• Adverse effects/complications (hypothermia, burns, worsening of pain, anaphylaxis, Irukandji syndrome)

Study Designs: Randomized controlled trials (RCTs) and non-randomized studies (non-randomized controlled trials, interrupted time series, controlled before-and-after studies, cohort studies), and unpublished scientific abstracts are eligible for inclusion. Trial protocols are excluded.

Timeframe: All years and all languages are included as long as there is an English abstract

PROSPERO Registration Not registered

Search Strategies: FA 7213 Jelly fish

Inclusion and Exclusion criteria

Randomized controlled trials (RCTs) and non-randomized studies (non-randomized controlled trials, interrupted time series, controlled before-and-after studies, cohort studies,) conference abstracts are eligible for inclusion. Trial protocols are excluded. All years and all languages are included as long as there is an English abstract

Risk of bias and certainty of the evidence

For the outcomes of pain relief, data was found from two randomized trials {Lopez 2000 503; Knudson 2016 512} with 45 participants and three observational trials {Yoshimoto 2002 300; Birsa 2010; Pyo 2016}. Confidence in the estimate of effect for the outcome was decreased due to the serious risk of bias, indirectness and imprecision. An insufficient number of studies were found to evaluate for publication bias.

Consensus on Science

• ● For the critical outcome of pain reduction (relief) we identified two randomized trials {Lopez 2000 503 503; Knudson 2016 512 512} with 45 participants and three observational trials {Yoshimoto 2002 300; Birsa 2010 426; Pyo 2016}.

• Three studies evaluated the effect of heat compared with other treatments {Lopez 2000 503; Knudson 2016 512; Yoshimoto 2002 300}. One randomized study {Lopez 2000 503} with very low certainty evidence (downgraded for bias and imprecision} that was published only in abstract form, randomized 27 callers to the Miami (US) Poison Center (either patients or health care providers) to receive instruction on hot water immersion (i) [110° F (43.3° C)] or ice packs (c) for pain relief of jellyfish stings. Three patients (2 from hot water, 1 from ice pack) were excluded for unspecified protocol violations. Participants were randomized to hot water or a cold pack on alternating days. The three patients that failed to obtain pain relief with ice packs were crossed over and experienced pain relief with hot water immersion. Hot water demonstrated a benefit in pain reduction as participants receiving hot water treatment had a relative risk of 1.600 (95% CI 0.9354-2.7367) for pain relief compared to those with ice pack therapy. A second randomized trial {Knudson 2016 512} with very low certainty evidence (downgraded for bias, indirectness and imprecision) published only in abstract form enrolled 18 participants in a study evaluating the efficacy of hot water immersion compared with topical lidocaine on stings from lion’s mane jellyfish (Cyanea capillata) tentacles. Cut tentacles were applied to each ankle of the participant and one ankle was the randomized to receive 5% topical lidocaine treatment (c) and the other hot water immersion (i) at 45° C. One-hundred mm VAS scores were collected regarding pain and itching, respectively, before treatment and at 30 minutes, 60 minutes and 24 hours post treatment. Pre-treatment VAS was 1.8 regarding pain and 3.4 regarding itching. Following treatment, VAS regarding pain for hot water immersion was 0.5 and for lidocaine was 1.3 at 30 minutes (p<0.05).

One observational study {Yoshimoto 2002 300} provided very low certainty evidence {downgraded for bias and imprecision} in a retrospective chart review of 32 cases analyzing the efficacy of heat application (i) (n=25 hot shower or hot compress) compared with opioid or non-opioid analgesics (c) or benzodiazepine (c) (n=7) in relieving pain, recorded as a dichotomous outcome, from jellyfish stings in Hawaii. Researchers evaluated signs of clinical improvement in pain within 20 minutes of receiving either heat treatment or an intravenous medication (recorded as an analgesic or benzodiazepine). An odds ratio of 11.5 (95% CI 1.007-131.28) was found regarding pain relief for heat application versus analgesics. An odds ratio of 23.0 (95% CI 1.40-378.90) was obtained for pain relief in heat application versus benzodiazepines. The temperature of the heat therapy was not recorded.

• Two studies evaluated the effect of different topical treatments on pain reduction {Birsa 2010 426; Pyo 2016 26}. One observational study {Birsa 2010} with very low certainty evidence (downgraded for bias, indirectness, and imprecision) was conducted in which two of the authors exposed the each of their inner forearms to either Chrysaora quinquecirrha (sea nettle) or Chiropsalmus quadrumanus (sea wasp) tentacles. Treatment solutions included lidocaine (15%, 10%, 5%, 3%, 1%) (i), benzocaine (5, 10% in ethanol) (i), ethanol (70%) (i), acetic acid (5%) (i), or ammonia (20%) (i) to one of the arms with the control of no treatment (c) being the opposite arm. Data is poorly presented. Lidocaine concentrations of 10 and 15% produced immediate relief; 4 and 5% solutions produced relief after approximately 1 min, while 1, 2 and 3% solutions required 10 to 20 min provide noticeable relief. Benzocaine provided some relief but took 10 or more minutes. Higher concentrations of lidocaine also resulted in fewer areas of redness. Areas of skin redness in contact with jellyfish tentacles were observed after treatment with benzocaine, acetic acid, or ethanol. A second observational study {Pyo 2016 26} with very low certainty evidence (downgraded for bias, indirectness and imprecision) evaluated pain in two health volunteers after treatment with distilled water (i), sea water (i), 10% lidocaine (i), 4% acetic acid (i), isopropanol (i), 20% ethanol (i) and 70% ethanol (i) or no treatment (c) after jellyfish sting. Tentacles from Nemopilema nomurai and Carybdea mora were harvested and two volunteers were exposed to the tentacles on the forearm for 3 minutes and then immediately treated by rinsing with approximately 5 mL the treatment solution. Participants were asked to rate their pain on a 0-6 scale (6 being worst). Raw data is not well recorded. Pain and redness were increased by treatment with 4% acetic acid, ethanol (20 and 70%) and isopropanol in Nemopilema nomurai stings compared with control. Sea water and 10% lidocaine provided pain relief and less erythema compared with control. In Carybdea mora stings, sea water and 10% lidocaine reduced pain and redness compared with control. 70% ethanol and isopropanol increased pain and redness compared with control.

• For the important outcome of adverse effects/complication we identified two observational studies {Birsa 2010 426; Pyo 2016 26}.

• One observational study {Birsa 2010 426} with very low certainty evidence (downgraded for bias, indirectness, and imprecision) was conducted in which two of the authors exposed each of their inner forearms to either Chrysaora quinquecirrha (sea nettle) or Chiropsalmus quadrumanus (sea wasp) tentacles. Topical treatment solutions included lidocaine (15%, 10%, 5%, 3%, 1%), benzocaine (5, 10% in ethanol), ethanol (70%), acetic acid (5%), or ammonia (20%)] to one of the arms with the control of no treatment being the opposite arm. More areas of skin redness were observed after treatment acetic acid, or ethanol than in control. A second observational study {Pyo 2016 26} with very low certainty evidence (downgraded for bias, indirectness and imprecision) evaluated pain in two healthy volunteers after topical treatment with distilled water, salt water, 10% lidocaine, 4% acetic acid, isopropanol, and 20% ethanol and 70% ethanol or nor treatment after jellyfish sting. Tentacles from Nemopilema nomurai and Carybdea mora were harvested and two volunteers were exposed to the tentacles on the forearm for 3 minutes and then immediately treated by rinsing with approximately 5 mL of the treatment solutions. Four percent acetic acid and isopropanol increased pain and redness following a sting with N. Nomurai tentacles, 70% ethanol and isopropanol increased pain and redness compared with control after sting by C. mura tentacles. In one randomized trial with low certainty evidence (downgraded for indirectness and imprecision)

• Due to the heterogeneity in data and the species of jellyfish tested, no metanalysis could be performed.

• No studies were identified for the critical outcomes of time to pain relief or survival or the important outcome of need for hospitalization.

Treatment Recommendations

Following a jellyfish sting, we recommend rinsing the area of the sting with sea water. (strong recommendation, low certainty of evidence)

For non-life threatening jellyfish envenomation we suggest the use of heated water (40-45° C) (immersion, irrigation or shower) or hot pack application compared with application of cold pack, topical lidocaine, benzocaine, vinegar/5% acetic acid, papain, bromalin, aluminum sulfate, sodium bicarbonate, to relieve pain from a jellyfish sting. (weak recommendation, very low certainty evidence)

We recommend against the use of topical 10% ammonia, isopropanol or ethanol for the treatment of jellyfish stings. (weak recommendation, low certainty of evidence)

Justification and Evidence to Decision Framework Highlights

In making these recommendations, the FA Task Force considered the following:

• This topic was prioritized by the FA Task Force based on the morbidity that jellyfish stings cause throughout the world. A systematic review {McGee 2023 CD009688} was completed in conjunction with the Cochrane Collaboration. This Consensus on Science incorporates both considerations from the Cochrane review as well as data from the randomized and non-randomized trials that were not included in the Cochrane review.

• Jellyfish envenomation is a common problem along coastal areas throughout the world. While the majority of envenomation s only result in local morbidity, systemic morbidity and mortality can occur with some species of jellyfish.

• Sea water should be available at the site of envenomation and requires no additional cost. This should preferentially be used to wash the area to remove remaining tentacles or nematocyts that are stuck to the skin.

• While hot water appears to demonstrate a benefit compared with other treatment, access to hot water may not be feasible in many parts of the world. Hot water may also lead to skin burns if the temperature is too hot. In some locations, solar-heated water bags and instant hot packs are available at beach lifeguard stations for treatment of jellyfish stings.

• While hot sea water would be preferred, it is recognized that only hot fresh water may be available. Fresh water may activate nematocysts remaining on the skin, therefore it is preferred to rinse the area of the string with sea water prior to application of hot fresh water.

• The studies in this and the Cochrane review used a range of 40°C to 45°C, one study used hot packs that were reported to be 43°C and one study used a “hot shower” that did not report the temperature. It may be most practical to use as warm water that the person can safely and comfortably tolerate.

• One study used hot packs that were reported to be 43° C. If hot water is not available, alternative sources of heat such as hot pack or hot sand could be used for treatment, taking extreme care to avoid items that are so hot that they burn the person.

• Commercially available sting relief products may be better packaged for the outdoor environment than household products which may need to be repackaged to optimize utility if used in the outdoor environment. This may increase the resources needed for household products.

• In the Cochrane systematic review, one study (Turner 1980) was identified in which methylated spirits (ethanol) resulted in increased pain following jellyfish sting compared to seawater control (RR 0.1111, 95% CI 0.0145 – 0.8500 for pain reduction). Two other studies (Birsa 2010, Pyo 2016), while data is poorly reported, report less improvement in pain with ethanol and isopropyl alcohol compared to sea water control.

• There may be differences in the efficacy of first aid treatments depending on the species of jellyfish causing the envenomation. In many instances it is not feasible for lay first aid providers to know the type of jellyfish resulting in the envenoming before beginning treatment.

Knowledge Gaps

• The studies in this and the Cochrane review used a range of 40°C to 45°C, one study used hot packs that were reported to be 43°C and one study used a “hot shower” that did not report the temperature. More studies are needed to determine the optimal temperature of the hot water used for treatment.

• There are many species of jellyfish throughout the world. Inconsistencies in study results may be secondary to the species of jellyfish used. More research is needed to determine the optimal treatments for all jellyfish species.

• This review did not find data on survival or need for hospitalization. There may be other treatments that affect these outcomes that were not included in this review.

EtD: FA 7213 Et D table jellyfish stings

References

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