DCS or DCI? The difference and why it matters
Simon J Mitchell
Professor Simon J Mitchell, Editor, Diving and Hyperbaric Medicine Journal. Department of Anesthesiology, University of Auckland. Private Bag 92019, Auckland 1142, New Zealand
Decompression illness; Decompression sickness; Arterial gas embolism; Pulmonary barotrauma; Terminology; Nomenclature
There are few issues that generate as much confusion in diving medicine as the nomenclature of bubble-induced dysbaric disease. Prior to the late 1980s, the diagnosis ‘decompression sickness’ (DCS) was invoked for symptoms presumed to arise as a consequence of bubble formation from dissolved inert gas during or after decompression. These bubbles were known to form within tissues, and also to appear in the venous blood (presumably after forming in tissue capillaries). A second diagnosis, ‘arterial gas embolism’ (AGE) was invoked for symptoms presumed to arise when bubbles were introduced directly to the arterial circulation as a consequence of pulmonary barotrauma.
Publication Type: Editorial
Diving Hyperb Med. 2019 September 30;49(3):154–160. doi: 10.28920/dhm49.3.154-160. PMID: 31523789. PMCID: PMC6881196.
Calculated risk of pulmonary and central nervous system oxygen toxicity: a toxicity index derived from the power equation
1 The Israel Naval Medical Institute, Haifa, Israel
2 Eliachar Research Laboratory, Western Galilee Medical Centre, Nahariya, Israel
Corresponding author: Dr Ran Arieli, 12 Klil-Hakhoresh, Rakefet, D N Misgav 0020175, Israel
Diving risk; Hyperoxia; Recovery; Oxygen limits; Algorithm
(Arieli R. Calculated risk of pulmonary and central nervous system oxygen toxicity: a toxicity index derived from the power equation. Diving and Hyperbaric Medicine. 2019 September 30;49(3):154–160. doi: 10.28920/dhm49.3.154-160. PMID: 31523789. PMCID: PMC6881196.)
Background: The risk of oxygen toxicity has become a prominent issue due to the increasingly widespread administration of hyperbaric oxygen (HBO) therapy, as well as the expansion of diving techniques to include oxygen-enriched gas mixtures and technical diving. However, current methods used to calculate the cumulative risk of oxygen toxicity during an HBO exposure i.e., the unit pulmonary toxic dose concept, and the safe boundaries for central nervous system oxygen toxicity (CNS-OT), are based on a simple linear relationship with an inspired partial pressure of oxygen (PO2) and are not supported by recent data.
Methods: The power equation: Toxicity Index = t2 × PO2c, where t represents time and c represents the power term, was derived from the chemical reactions producing reactive oxygen species or reactive nitrogen species.
Results: The toxicity index was shown to have a good predictive capability using PO2 with a power 'c' of 6.8 for CNS-OT and 4.57 for pulmonary oxygen toxicity. The pulmonary oxygen toxicity index (PO2 in atmospheres absolute, time in h) should not exceed 250. The CNS-OT index (PO2 in atmospheres absolute, time in min) should not exceed 26,108 for a 1% risk.
Conclusion: The limited use of this toxicity index in the diving community, after more than a decade since its publication in the literature, establishes the need for a handy, user-friendly implementation of the power equation.
Publication Type: Original article
Diving Hyperb Med. 2019 September 30;49(3):161–166. doi: 10.28920/dhm49.3.161-166. PMID: 31523790. PMCID: PMC6881197.
Increasing prevalence of vestibulo-cochlear decompression illness in Malta – an analysis of hyperbaric treatment data from 1987–2017
Charles Paul Azzopardi1,4, Joseph Caruana2,3, Lyubisa Matity1, Stephen Muscat1, WA Jack Meintjes4
1 Hyperbaric Unit, Mater Dei Hospital, Malta
2 Department of Physics, University of Malta, Malta
3 Institute of Space Sciences and Astronomy, University of Malta, Malta
4 Department of Interdisciplinary Health Sciences, University of Stellenbosch, South Africa
Corresponding author: Dr Charles Paul Azzopardi, Hyperbaric Unit, Mater Dei Hospital, Triq id-Donaturi tad-Demm, Tal-Qroqq, Msida, Malta
Decompression sickness; Diving; Scuba; Recompression; Symptoms
(Azzopardi CP, Caruana J, Matity L, Muscat S, Meintjes WAJ. Increasing prevalence of vestibulo-cochlear decompression illness in Malta – an analysis of hyperbaric treatment data from 1987–2017. Diving and Hyperbaric Medicine. 2019 September 30;49(3):161–166. doi: 10.28920/dhm49.3.161-166. PMID: 31523790. PMCID: PMC6881197.)
Introduction: Scuba diving is a big part of the tourism sector in Malta, and all the cases of decompression illness (DCI)are treated within the single hyperbaric referral centre in the country.
Methods: This retrospective analysis reviews all the medical records of divers with DCI in Malta within the 30-year period between 1987 to 2017 who required recompression therapy with hyperbaric oxygen.
Results: There were 437 discrete cases of DCI managed with recompression therapy. Amongst DCI subtypes, the prevalence of musculo-skeletal DCI is decreasing, whereas that of vestibulo-cochlear DCI is increasing.
Conclusion: The increasing prevalence of vestibulo-cochlear DCI may be due to a change in diving practices in Malta.
Publication Type: Original article
Diving Hyperb Med. 2019 September 30;49(3):167–174. doi: 10.28920/dhm49.3.167-174. PMID: 31523791. PMCID: PMC6884101.
Seizure frequency in more than 180,000 treatment sessions with hyperbaric oxygen therapy – a single centre 20-year analysis
Diogo A Costa1,2,3, José S Ganilha1,2, Pedro C Barata4, Francisco G Guerreiro1,2
1 Centro de Medicina Subaquática e Hiperbárica (CMSH), Portuguese Navy, Portugal
2 Centro de Investigação Naval (CINAV), Portuguese Navy, Portugal
3 Department of Haematology and Oncology, CUF Instituto de Oncologia, Lisbon, Portugal
4 Department of Internal Medicine, Section of Hematology and Medical Oncology, Tulane Medical School, New Orleans, United States
Corresponding author: Dr Diogo A Costa, Centro de Medicina Subaquática e Hiperbárica (CMSH), Azinhaga dos Ulmeiros, 1649-020 Lisboa, Portugal
Hyperbaric oxygen therapy; Hyperbaric oxygen; Toxicity; Side effects; Hyperoxia; Central nervous system; Seizure
(Costa DA, Ganilha JS, Barata PC, Guerreiro FG. Seizure frequency in more than 180,000 treatment sessions with hyperbaric oxygen therapy - a single centre 20-year analysis. Diving and Hyperbaric Medicine. 2019 September 30;49(3):167–174. doi: 10.28920/dhm49.3.167-174. PMID: 31523791. PMCID: PMC6884101.)
Introduction: Hyperbaric oxygen therapy (HBOT) involves the risk of central nervous system oxygen toxicity (CNS-OT), including seizures in patients breathing oxygen at pressures ≥ 2 atmospheres absolute. This study aimed to determine the seizure frequency and assess the clinical benefit of a 5-minute air-break (5´-AIRBK).
Methods: Twenty-year (1999–2018) retrospective analysis of all consecutive treatments with HBOT. Medical records were reviewed to determine patient demographics, comorbidities, HBOT indications, and seizure characteristics and timing. Seizure frequency was compared before and after incorporating a 5´-AIRBK in the treatment protocol. Chi-square testing was performed using SPSS (version 24.0); P < 0.05 was accepted as statistically significant.
Results: We evaluated 188,335 HBOT sessions (74,255 before versus 114,080 after introducing a 5´-AIRBK). A total of 43 seizures were observed: 29 before and 14 after the 5´-AIRBK introduction (3.9 versus 1.2 per 10,000 treatments; P < 0.0001). Seizures occurred after a median of 57 (range 15–85) minutes following compression and after a median of 21 HBOT sessions (1–126). Patients experiencing seizures were undergoing treatment for: diabetic ulcer (n = 11); acute traumatic peripheral ischaemia (ATPI) (n = 6); non-diabetic ulcer (n = 5); sudden sensorineural hearing loss (n = 5); chronic refractory osteomyelitis (n = 5); radionecrosis (n = 3); necrotising fasciitis (NF) (n = 2); and haemorrhagic cystitis after allogeneic bone marrow transplantation (n = 1). ATPI and NF had a considerably higher relative frequency of seizures compared to other indications.
Conclusions: A statistically significant lower seizure frequency was achieved with a 5´-AIRBK. Assessing and defining the appropriate patient/treatment profile can be useful to minimise the risk of CNS-OT.
Publication Type: Original article
Diving Hyperb Med.2019 September 30;49(3):175–185. doi: 10.28920/dhm49.3.175-185. PMID: 31523792. PMCID: PMC6884100.
Only minor stem cell mobilization in head and neck irradiated patients treated with hyperbaric oxygen
Lone Forner1,3, Adela Berkowicz2, Ebbe Dickmeiss2, Ole Hyldegaard3, Erik C Jansen3, Anne Fischer-Nielsen2
1 Department of Oral and Maxillofacial Surgery, Centre for Head and Orthopedics and Department of Anaesthesia, Copenhagen University Hospital, Copenhagen, Denmark
2 Cell Therapy Facility, Department of Clinical Immunology, Centre of Diagnostic Investigation, Copenhagen University Hospital, Copenhagen, Denmark
3 Department of Anaesthesia, Centre for Head and Orthopedics, Copenhagen University Hospital, Copenhagen, Denmark
Corresponding author: Dr Lone Forner, Department of Oral and Maxillofacial Surgery, Centre for Head and Orthopedics and Department of Anaesthesia, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
Head and neck cancer; Hyperbaric oxygen; Osteoradionecrosis; Platelets; Soft-tissue radionecrosis; Stem cells
(Forner L, Berkowicz A, Dickmeiss E, Hyldegaard O, Jansen EC, Fischer-Nielsen A. Only minor stem cell mobilization in head and neck irradiated patients treated with hyperbaric oxygen. Diving and Hyperbaric Medicine. 2019 September 30;49(3):175–185. doi: 10.28920/dhm49.3.175-185. PMID: 31523792. PMCID: PMC6884100.)
Introduction: Hyperbaric oxygen, (HBO) is used to treat several conditions including late radiation tissue injury. Previous studies have suggested that HBO mobilizes bone marrow derived stem/progenitor cells (SPC) to the peripheral blood, however possible cumulative effects were highly variable.
Methods: We have investigated a possible HBO-induced mobilization of SPCs by determining CD34+CD45dim cell numbers, as well as SPCs in general. The latter were characterized by high aldehyde dehydrogenase (ALDH) activity by use of the Aldefluor® assay. We included ten patients admitted for HBO treatment of radiation tissue injury. Six patients completed the 29–30 HBO treatment exposures. We also investigated possible HBO-induced effects on platelet activation as measured by flow cytometry and functional analyses.
Results: We found a weak and insignificant tendency toward mobilization of CD34+CD45dim cells after a single HBO exposure versus before. Additionally, we found an additive effect of 15 HBO exposures on the increase in CD34+CD45dim cells relative to the pre-1st-HBO values. These changes were significantly more than zero but less than a doubling. We could not demonstrate a significant effect of HBO on the content of Aldefluor® positive SPCs in peripheral blood. There was no significant effect on platelet activation overall. However, in patients with increased expression of activation markers at baseline, we found a decrease after one exposure although this was not reflected in functional tests.
Conclusion: We found a minor statistically significant mobilizing effect HBO treatment on the bone marrow derived stem/progenitor cell content in peripheral blood after 15 treatments (n = 10 patients), but no effect after 30 treatments (n = 6 patients). However, because of the low number of patients we cannot confidentially prove or disprove the null hypothesis. The possibility that HBO treatment reduces the number of activated platelets could not be demonstrated nor excluded.
Publication Type: Original article
Diving Hyperb Med. 2019 September 30;49(3):186–191. doi: 10.28920/dhm49.3.186-191. PMID: 31523793. PMCID: PMC6881200.
Assessment of sensory sensitivity through critical flicker fusion frequency thresholds after a maximum voluntary apnoea
Francisco de Asís Fernández1, Fernando González-Mohino2, José M González-Ravé3
1 Departament of Health, Centro Superior de Estudios Universitarios La Salle. Universidad Autónoma de Madrid, Spain
2 Faculty of Languages and Education, University of Nebrija, Madrid, Spain
3 Sports Training Laboratory, Faculty of Sports Sciences, University of Castilla-La Mancha, Toledo, Spain
Corresponding author: Dr Francisco de Asís Fernández, Departament of Health, Centro Superior de Estudios Universitarios La Salle. Universidad Autónoma de Madrid, Spain
Brain; Breath-hold diving; Exercise; Fatigue; Hypoxia
(de Asís Fernandez F, González-Mohino F, González-Ravé J. Assessment of sensory sensitivity through critical flicker fusion frequency thresholds after a maximum voluntary apnoea. Diving and Hyperbaric Medicine. 2019 September 30;49(3):186–191. doi: 10.28920/dhm49.3.186-191. PMID: 31523793. PMCID: PMC6881200.)
Introduction: The influence of acute exercise on sensory sensitivity (SS) differs according to the type and duration of exercise performed. In the present study, we assessed changes on SS soon after a maximal dynamic apnoea.
Methods: Thirty-nine experienced male breath-hold divers were recruited. Critical flicker fusion frequency (CFFF) thresholds were used to measure SS. Thresholds were determined before and after a maximal dynamic apnoea. Immediately after surfacing, heart rate and oxygen saturation (SpO2) were recorded for two minutes.
Results: After maximal dynamic apnoea, SpO2 was significantly decreased (from mean 97.3% pre-dive to mean 63.1% post-dive; P < 0.0001; η2 P = 0.86), but this acute hypoxaemia did not trigger changes in SS (post-dive value 102% of baseline; P = 0.22; η2 P = 0.03). Pearson correlation analysis revealed a moderate association between SS with swimming speed
(r = 0.423) and apnoea time (r = -0.404).
Conclusions: A maximal dynamic apnoea did not produce changes in central nervous system fatigue or cortical arousal. We found no relationship between the hypoxaemia level reached after a maximal apnoea and changes in the CFFF thresholds. This study suggests that the time of exposure to hypoxia during a maximal voluntary apnoea is not enough to produce changes in SS.
Publication Type: Original article
Diving Hyperb Med. 2019 September 30;49(3):192–203. doi: 10.28920/dhm49.3.192-203. PMID: 31523794. PMCID: PMC6884103.
Snorkelling and breath-hold diving fatalities in Australia, 2001 to 2013. Demographics, characteristics and chain of events
1 DAN Asia-Pacific Foundation / Australasian Diving Safety Foundation, Ashburton, Victoria, Australia
2 Department of Public Health and Preventative Medicine, Monash University, Victoria, Australia
Corresponding author: John Lippmann, DAN Asia-Pacific Foundation / Australasian Diving Safety Foundation, PO Box 478, Canterbury, VIC 3126, Australia
Breath-hold diving; DAN – Divers Alert Network; Diving deaths; Fatalities; Immersion; Snorkelling
(Lippmann J. Snorkelling and breath-hold diving fatalities in Australia, 2001 to 2013. Demographics, characteristics and chain of events. Diving and Hyperbaric Medicine. 2019 September 30;49(3):192–203. doi: 10.28920/dhm49.3.192-203. PMID: 31523794. PMCID: PMC6884103.)
Introduction: The aim of this study was to identify characteristics of victims of fatal snorkelling and breath-hold diving accidents in Australia from 2001–2013, inclusive, to determine underlying factors and risks associated with such activities and inform appropriate countermeasures.
Methods: The National Coronial Information System (NCIS) was searched to identify snorkelling and breath-hold diving-related cases reported to Australian coroners for the years 2001–2013, inclusive. Coronial data in the form of findings, witness and police reports, medical histories and autopsies were collected and collated, and descriptive statistics were used to analyse these data. A chain of events analysis was used to determine the likely sequence of events.
Results: There were 175 identified snorkelling-related fatalities during the study period. Most victims were middle-aged males (mean age 49 years). Pre-existing health conditions were possible contributors to 41% of the deaths, the main being ischaemic heart disease. The majority of deaths occurred in Queensland in inexperienced snorkellers, often in commercial settings. The victim’s plight often went unnoticed as they were alone, or poorly supervised, when the incident occurred. Apnoeic hypoxia appeared to have been associated with at least 12.5% of the deaths. The main disabling injuries were asphyxia (40%) and cardiac incidents (35%).
Conclusion: Human factors, such as chronic health conditions, poor skills and inexperience and poor planning can play a substantial role throughout the chain of events leading to a snorkelling fatality. It is important to educate the community, doctors and dive industry professionals about potential problems associated with the interaction between certain health-related conditions, especially cardiovascular conditions, and snorkelling. Close supervision is strongly recommended for inexperienced snorkellers due to their likely poor skills, as well as for experienced breath-hold divers due to the potential for apnoeic hypoxia.
Publication Type: Original article
Diving Hyperb Med. 2019 September 30;49(3):204–208. doi: 10.28920/dhm49.3.204-208. PMID: 31523795. PMCID: PMC6884094.
Descriptive study of diving injuries in the Canary Islands from 2008 to 2017
Fernando Guillén-Pino1, Armando Morera-Fumero1, Manuel Henry-Benítez1, Emilio Alonso-Lasheras2, Pedro Abreu-González3, Vicente Medina-Arana4
1 Department of Internal Medicine, Dermatology and Psychiatry, Facultad de Ciencias de la Salud, Universidad de La Laguna, Santa Cruz de Tenerife, Canary Islands, Spain
2 Hyperbaric Medicine Unit, Canary Islands University Hospital, Santa Cruz de Tenerife, Canary Islands, Spain
3 Department of Medical Basic Science (Physiology Unit), Facultad de Ciencias de la Salud, Universidad de La Laguna, Santa Cruz de Tenerife, Canary Islands, Spain
4 Department of Surgery, Facultad de Ciencias de la Salud, Universidad de la Laguna, Santa Cruz de Tenerife, Canary Islands, Spain
Corresponding author: Fernando Guillén-Pino. Departamento de Medicina Interna, Dermatología y Psiquiatría (Unidad de Psiquiatría). Facultad de Ciencias de la Salud, Campus de Ofra, Universidad de La Laguna (ULL), 38071, Santa Cruz de Tenerife, Canary Islands, Spain
Diving incidents; Epidemiology; Scuba diving; First aid; Hyperbaric oxygen therapy; Tourism
(Guillén-Pino F, Morera-Fumero A, Henry-Benítez M, Alonso-Lasheras E, Abreu-González P, Medina-Arana V. Descriptive study of diving injuries in the Canary Islands from 2008 to 2017. Diving and Hyperbaric Medicine. 2019 September 30;49(3):204–208. doi: 10.28920/dhm49.3.204-208. PMID: 31523795. PMCID: PMC6884094.)
Introduction: This research reports the epidemiology of diving injuries managed in the Hyperbaric Medicine Unit of the Canary Islands University Hospital.
Methods: Data were extracted from the clinical records of all divers injured and admitted to the unit for treatment of dysbaric diving injuries between 2008 and 2017, inclusive.
Results: One-hundred and thirty diving injuries were recorded. Most (71%) occurred in men and 43% were foreigners. Eighteen per cent either had no diving certification or that information was not recorded in the clinical chart. Only a third of the 40% of divers who had some form of on-site first aid treatment received oxygen and oral rehydration. Type 1 decompression sickness (DCS) was diagnosed in 56 divers (43%) and Type 2 in 67 (52%), whilst seven were treated for omitted decompression. At discharge, 122 (94%) were asymptomatic, whilst 5% experienced some residual sensory or other changes. One diver who presented late remained quadriparetic and one, admitted in a state of coma, died. Only 76% of the injured divers had specific diving accident insurance and, of those, 58% were foreign divers.
Conclusions: Over half of the injured divers did not receive any on-site first aid. The majority (94%) of treated injured divers were discharged without sequelae. Based on these data, several public health recommendations for the Canary Islands are made.
Publication Type: Review article
Diving Hyperb Med. 2019 September 30;49(3):209–215. doi: 10.28920/dhm49.3.209-215. PMID: 31523796. PMCID: PMC6884102.
Evidence for simulation-based education in hyperbaric medicine: A systematic review
Sylvain Boet1–4, Olivia Cheng-Boivin5, Leonardo Martin5, Tomi Hurskainen1, Cole Etherington1,3
1 Department of Anesthesiology and Pain Medicine, The Ottawa Hospital, Ottawa, Ontario, Canada
2 Hyperbaric Medicine Unit, The Ottawa Hospital, Ottawa, Ontario, Canada
3 The Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, Ontario, Canada
4 Department of Innovation in Medical Education, University of Ottawa, Ottawa, Ontario, Canada
5 Medical Student, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
Corresponding author: Associate Professor Sylvain Boet, Department of Anesthesiology and Pain Medicine, Hyperbaric Medicine Unit, The Ottawa Hospital, 501 Smyth Rd, Critical Care Wing 1401, Ottawa, K1H 8L6, Ontario, Canada
Hyperbaric oxygen; Education; Systematic review; Performance; Safety
(Boet S, Cheng-Boivin O, Martin L, Hurskainen T, Etherington C. Evidence for simulation-based education in hyperbaric medicine: A systematic review. Diving and Hyperbaric Medicine. 2019 September 30;49(3):209–215. doi: 10.28920/dhm49.3.209-215. PMID: 31523796. PMCID: PMC6884102.)
Introduction: Evidence from many areas of healthcare suggests that skills learned during simulation transfer to clinical settings; however, this has not yet been investigated in hyperbaric medicine. This systematic review aimed to identify, summarize, and assess the impact of simulation-based education in hyperbaric medicine.
Methods: Eligible studies investigated the effect of simulation-based education for learning in hyperbaric medicine, used any design, and were published in English in a peer-reviewed journal. Learning outcomes across all Kirkpatrick levels were included. MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched. Pairs of independent reviewers assessed references for study eligibility.
Results: We found no article assessing the impact of simulation-based education in hyperbaric medicine published in English. Only one potentially relevant paper published in German was found.
Conclusions: More research is needed to determine how the hyperbaric medicine community and their patients may benefit from simulation-based education to optimize both practice and patient care.
Publication Type: Review article
Diving Hyperb Med. 2019 September 30;49(3):216–224. doi: 10.28920/dhm49.3.216-224. PMID: 31523797. PMCID: PMC6884104.
Is there a role for hyperbaric oxygen therapy in the treatment of refractory wounds of rare etiology?
Pasquale Longobardi1, Klarida Hoxha1, Michael H Bennett2
1 Centro Iperbarico (Hyperbaric Medicine and Wound Care Centre), Ravenna, Italy
2 Department of Anaesthesia, University of New South Wales, Sydney, Australia
Corresponding author: Dr Pasquale Longobardi, Chief Medical Director, Centro Iperbarico, via Augusto Torre 3, 48124 Ravenna, Italy
Calciphylaxis; Economics; Epidemiology; Hyperbaric medicine; Review article; Skin; Nitric oxide
(Longobardi P, Hoxha K, Bennett MH. Is there a role for hyperbaric oxygen therapy in the treatment of refractory wounds of rare etiology? Diving and Hyperbaric Medicine. 2019 September 30;49(3):216–224. doi: 10.28920/dhm49.3.216-224. PMID: 31523797. PMCID: PMC6884104.)
Introduction: Delayed wound healing indicates wounds that have failed to respond to more than 4–6 weeks of comprehensive wound care. Wounds with delayed healing are a major source of morbidity and a major cost to hospital and community healthcare providers. Hyperbaric oxygen therapy (HBOT) is a treatment designed to increase the supply of oxygen to wounds and has been applied to a variety of wound types. This article reviews the place of HBOT in the treatment of non-healing vasculitic, calcific uremic arteriolopathy (CUA), livedoid vasculopathy (LV), pyoderma gangrenosum (PG) ulcers.
Methods: We searched electronic databases for research and review studies focused on HBOT for the treatment of delayed healing ulcers with rare etiologies. We excluded HBOT for ulcers reviewed elsewhere.
Results: We included a total of three case series and four case reports including 63 participants. Most were related to severe, non-healing ulcers in patients with vasculitis, CUA, LV, and PG. There was some evidence that HBOT may improve the healing rate of wounds by increasing nitric oxide (NO) levels and the number of endothelial progenitor cells in the wounds. HBOT may also improve pain in these ulcers.
Conclusion: We recommend the establishment of comprehensive and detailed wound care registries to rapidly collect prospective data on the use of HBOT for these problem wounds. There is a strong case for appropriately powered, multi-centre randomized trials to establish the true efficacy and cost-effectiveness of HBOT especially for vasculitis ulcers that have not improved following immunosuppressive therapy.
Publication Type: Review article
Diving Hyperb Med. 2019 September 30;49(3):225–228. doi: 10.28920/dhm49.3.225-228. PMID: 31523798. PMCID: PMC6881212.
A diver’s guide to subaquatic envenomation in the Mediterranean
James Todd1, Mark Edsell2
1 St George’s University of London, Tooting, London, UK
2 Department of Anaesthetics, St George’s Hospital, London, UK
Corresponding author: James Todd, 21 Lavender Avenue, Mitcham, CR4 3HL, United Kingdom
Marine animals; Diving; Treatment; First aid; Flow chart
(Todd J, Edsell M. A diver’s guide to subaquatic envenomation in the Mediterranean. Diving and Hyperbaric Medicine. 2019 September 30;49(3):225–228. doi: 10.28920/dhm49.3.225-228. PMID: 31523798. PMCID: PMC6881212.)
Introduction: Between 40,000 and 50,000 divers and swimmers are envenomated each year and diving as a hobby is becoming increasingly popular. In the Mediterranean, envenomation is most often by Weever fish, Scorpion fish and jellyfish but coral and sea urchins may also be venomous.
Envenomation: Most stings cause local inflammation, oedema and pain. The severity of pain varies with the venom and the amount injected. In severe cases, stings may be life-threatening due to cardiogenic or anaphylactic shock or penetration of vital structures.
Management: Most cases of envenomation are preventable with a combination of measures including the avoidance of contact through good buoyancy control, the wearing of body-suits, and by maintaining visual awareness. Immediate management is to return to the surface, elevate and wash the site of injury. Immersion in hot water followed by simple analgesics for pain relief has been shown to be more effective than other methods. More severe cases should be identified by symptoms including confusion and heavy bleeding and referred to qualified medical care.
Conclusion: Envenomation by subaquatic species is common and preventable yet the dissemination of the appropriate knowledge is limited. This knowledge summary provides pertinent information aimed at divers in preventing and managing such injuries.
Publication Type: The world as it is
Diving Hyperb Med. 2019 September 30;49(3):229–232. doi: 10.28920/dhm49.3.229-232. PMID: 31523799. PMCID: PMC6881213.
A case report of cerebral arterial gas embolism (CAGE) associated with Takotsubo cardiomyopathy
Denise McCool1,2, Chris Butler2, John Evans3, Carsten Aase1,2
1 Hyperbaric Medicine Unit, The Townsville Hospital, Townsville, Australia
2 Department of Anaesthesia, The Townsville Hospital, Townsville, Australia
3 Department of Intensive Care, The Townsville Hospital, Townsville, Australia
Corresponding author: Dr Denise McCool, Hyperbaric Medicine Unit, The Townsville Hospital, 100 Angus Smith Dr, Douglas QLD 4814, Australia
Barotrauma; Hyperbaric oxygen therapy; Pulmonary barotrauma; Pulmonary oedema; Recreational diving; Salt water aspiration; Scuba
(McCool D, Butler C, Evans J, Aase C. A case report of cerebral arterial gas embolism (CAGE) associated with Takotsubo cardiomyopathy. Diving and Hyperbaric Medicine. 2019 September 30;49(3):229–232. doi: 10.28920/dhm49.3.229-232. PMID: 31523799. PMCID: PMC6881213.)
A 43-year-old female scuba diver was retrieved and treated following a rapid ascent and presumed cerebral arterial gas embolism (CAGE). She subsequently developed respiratory distress and was found to have Takotsubo cardiomyopathy, with transient left ventricular dysfunction, elevated cardiac enzymes, and normal CT coronary angiography. We believe this to be the first report of CAGE associated with Takotsubo cardiomyopathy.
Publication Type: Case report