Article – 1 - Crush injury and other acute traumatic ischaemias
Title: Case report: Treatment of mild traumatic brain injury with hyperbaric oxygen.
Authors: Wright, JK; Zant, E; Groom, K; Schlegel, RE; Gilliland, K
Digital Object Identifier (or PMID etc): Nil
Keywords: Nil
Abstract: Two United States Air Force Airmen were injured in a roadside improvised explosive device (IED) blast in Iraq in January 2008. Both airmen suffered concussive injuries and developed irritability, sleep disturbances, headaches, memory difficulties and cognitive difficulties as symptoms of mild traumatic brain injury (mTBI). Six months after injury, repeat Automated Neuropsychological Assessment Metrics (ANAM) testing showed deterioration, when compared to pre-injury baseline ANAM assessment, in all measured areas (simple reaction time, procedural reaction time, code substitution learning, code substitution delayed, mathematical processing, and matching to sample). The airmen were treated with hyperbaric oxygen in treatments of 100% oxygen for one hour at 1.5 atmospheres absolute, resulting in rapid improvement of headaches and sleep disturbances, improvement in all symptoms and resolution of most symptoms. Repeat ANAM testing after completion of the hyperbaric treatments - nine months after initial injury - showed improvement in all areas, with most measures improving to pre-injury baseline levels. The airmen received no other treatment besides medical monitoring. Repeat neuropsychologic testing confirmed the improvement.
Conclusion: We conclude that the improvement in symptoms and ANAM performance is most likely attributable to HBO treatment.
Article – 2 - Crush injury and other acute traumatic ischaemias
Title: A systematic review of the use of hyperbaric oxygen therapy in the treatment of acute traumatic brain injury. The Cochrane Database of Systematic Reviews 2004
Authors: Bennett, MH; Trytko, BE; Jonker, B
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Abstract: We aimed to assess the randomised clinical evidence for the benefits and harms of adjunctive hyperbaric oxygen therapy (HBOT) for acutely brain-injured patients. HBOT can improve oxygen supply to the injured brain and reduce both cerebral oedema and cerebrospinal fluid pressure and might therefore result in a reduction in patient death and disability. We performed a systematic search of the literature for randomised controlled trials and made pooled analyses of pre-determined clinical outcomes where possible using Cochrane Collaboration methodology. We included adults with serious closed head injury requiring admission to an intensive care environment and included trials must have compared a standard therapy with adjunctive HBOT to standard therapy alone following randomised allocation. We pre-determined important clinical outcomes and assessed them when reported in the primary studies.
Results: Four trials contributed to this review (382 participants, 199 receiving HBOT and 183 control). Pooled analysis suggested a significant reduction in the risk of dying when HBOT was added (RR 0.69, 95% CI 0.54 to 0.88, NNT = 7, P = 0.003), but no statistically significant increase in the chance of a favourable clinical outcome (RR 1.94, 95% CI 0.92 to 4.08, P = 0.08).
Conclusion: HBOT reduced the risk of death but did not clearly increase the chance of favourable clinical outcome. Routine application of HBOT to these patients should not be justified from this review. More research of high methodological rigour is needed in order to confirm or refute the findings of this review.
Article – 3 - Crush injury and other acute traumatic ischaemias
Title: The safe treatment, monitoring and management of severe traumatic brain injury patients in a monoplace chamber.
Authors: Gossett, WA; Rockswold, GL; Rockswold, SB; Adkinson, CD; Bergman, TA; Quickel, RR
Digital Object Identifier (or PMID etc): Nil
Keywords: Nil
Abstract: This report describes how 27 patients with severe traumatic brain injury were safely treated, monitored and managed in a monoplace chamber that was compressed with air to 1.5 atmospheres absolute (152 kPa). A total of 75 hyperbaric oxygen treatments were delivered using the monoplace system described, with all patients receiving 100% oxygen via mechanical ventilation. Specific pieces of equipment, components and features were selected, and modifications were interfaced to safely and effectively treat these critically ill patients in a monoplace chamber.
Conclusion: Patient monitoring included cardiovascular and ventilatory parameters as well as intracranial pressure, brain tissue oxygen levels, brain temperature and cerebral microdialysis. The chamber and all the supporting equipment for ventilating, monitoring and managing the patient functioned well.
Article – 4 - Crush injury and other acute traumatic ischaemias
Title: Influence of delayed hyperbaric oxygenation on recovery from mechanically induced damage.
Authors: Nelson, AG; Wolf Jr, EG; Li, B
Digital Object Identifier (or PMID etc): PMID: 8061559
Keywords: Nil
Abstract: This study examined whether subjecting a crushed muscle to a delayed intermittent hyperbaric oxygenation protocol would facilitate healing, the marker for healing being a return toward 100% uncrushed muscle in selected mechanical, morphologic, and biochemical parameters. Thirty-six rabbits (4 groups of 9) had the right lateral head of their gastrocnemius muscle surgically crushed. After surgery, the rabbits were exposed daily for 90 min 5 days/wk to either 100% O2 at 243 kPa, 8.5% O2 and 91.5% N2 at 243 kPa, 100% O2 at 101 kPa, or 21% O2 at 101 kPa. Initial treatments were administered 16-18 h post-muscle crush. After 10 days of treatment, maximal twitch and tetanic tension of the crushed muscle and its contralateral counterpart were measured. The muscles were then removed and analyzed morphologically, and the activity of citrate synthase, phosphofructokinase, and glucose-6-phosphate dehydrogenase were measured. The treatment group means for any of the parameters measured were not significantly different from each other.
Conclusion: The extent of muscle damage, however, was determined to be minor as the control group recovery threshold was approximately 80%. Thus, it seems that the treatment protocol used does not facilitate healing for this type of muscle crush injury.
Article – 5 - Crush injury and other acute traumatic ischaemias
Title: A role for oxygen-induced osmosis in hyperbaric oxygen therapy.
Authors: Hills, BA
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Abstract: The principles of gas-induced osmosis, demonstrated in the 1970s, have been applied to the very large steady-state gradients of O2 arising between arterial blood and hypoxic tissue during hyperbaric oxygen (HBO) therapy to produce a fluid ‘pump’ in the desired direction for resolving accompanying oedema. Thus, in soft-tissue injuries, an oxygen-induced fluid pump would break the vicious cycle between ischaemia, hypoxia and oedema at the point of oedema rather than hypoxia, as hitherto assumed. This osmotic mechanism enables the successes of HBO therapy in hypoxic disorders to be reconciled with early failures in such areas as hyperbaric radiotherapy, where substitution of O2 for N2 in inspired air was clearly not reflected at the tissue level. This argument also applies to the success of HBO in treating air embolism and decompression sickness over simple compression.
Conclusion: The oxygen pump would seem to offer a more plausible explanation for the success of HBO therapy than theories based upon O2 delivery by the circulation, especially when considering cardiovascular reflexes to elevated PaO2 and the marginal increase in blood O2 content upon switching to HBO from normobaric oxygen breathing. Hills BA. A role for oxygen-induced osmosis in hyperbaric oxygen therapy. Note: reprinted from Medical Hypothesis 1999; 52(3): 259-263.
Article – 6 - Crush injury and other acute traumatic ischaemias
Title: Effect of hyperbaric oxygenation on peripheral nerve regeneration in adult male rabbits.
Authors: Bradshaw, PO; Nelson, AG; Fanton, JW; Yates, T; Kagan-Hallet, KS
Digital Object Identifier (or PMID etc): PMID: 8840479
Keywords: Nil
Abstract: Oxygen environments were used to study the regenerative effects of hyperbaric oxygen on crushed sciatic nerves in 30 adult male rabbits. Six different oxygen environments were used, and treatments were initiated 4 days post injury. Transmission electron microscopy and light microscopy were used to evaluate the regenerative morphology of crushed nerves. The morphology of crushed nerves after 7 wk of treatment with compressed oxygen at 202, 242, and 303 kPa resembled normal uncrushed nerves, with nerve fibers uniformly distributed throughout the section. The treatment groups receiving 202 kPa compressed air, 100% normobaric oxygen, or ambient air did not display morphologies similar to normal uncrushed nerve. The nerves in these animals were edematous and contained disarrayed nerve fibers. Myelination in the animals receiving 100% O2 at high pressures resembled undamaged nerves. Collagen and blood vessels were more evident in the lower pressure/oxygen tension treatments than in the animals receiving 100% O2 at higher pressures. The neurofilamentous material inside the crushed control axons was dense, whereas in the axons of animals treated with compressed O2 it was loosely packed.
Conclusion: These differences in morphology suggest that treatments consisting of 100% O2 under pressure can accelerate a peripheral nerve's recovery from a crush injury.
Article – 7 - Crush injury and other acute traumatic ischaemias
Title: Regional CBF in chronic stable TBI treated with hyperbaric oxygen.
Authors: Barrett, KF; Masel, B; Patterson, J; Scheibel, RS; Corson, K; Mader, JT
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Abstract: To investigate whether Hyperbaric Oxygen Therapy (HBO2) could improve neurologic deficits and regional cerebral blood flow (rCBF) in chronic traumatic brain injuries (TBI), the authors employed a nonrandomized control pilot trial. Five subjects, at least three years post head injury, received HBO2. Five head injured controls (HIC) were matched for age, sex, and type of injury. Five healthy subjects served as normal controls. Sixty-eight normal volunteers comprised a reference data bank against which to compare SPECT brain scans. HBO2 subjects received 120 HBO2 in blocks of 80 and 40 treatments with an interval five-month break. Normal controls underwent a single SPECT brain scan, HBO2, and repeat SPECT battery. TBI subjects were evaluated by neurologic, neuropsychometric, exercise testing, and pre and post study MRIs, or CT scans if MRI was contraindicated. Statistical Parametric Mapping was applied to SPECT scans for rCBF analysis.
Conclusion: There were no significant objective changes in neurologic, neuropsychometric, exercise testing, MRIs, or rCBF. In this small pilot study, HBO2 did not effect clinical or regional cerebral blood flow improvement in TBI subjects.
Article – 8 - Crush injury and other acute traumatic ischaemias
Title: Critical appraisal: Hyperbaric oxygen therapy significantly reduced pain and swelling and increased wrist range of movement in patients with early CRPS
Authors: Bennett, MH
Digital Object Identifier (or PMID etc): Nil
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Abstract: Clinical bottom line 1 There was a significant difference in favour of HBOT for pain, oedema and wrist flexion at day 45 after the start of the trial. 2 Functional significance for the patients is unknown. 3 No patient in either arm progressed to the atrophic stage of complex regional pain syndrome (CRPS). Citation Kiralp MZ, Yildiz S, Vural D, Kesin I, Ay H, Dursun H. Effectiveness of hyperbaric oxygen therapy in the treatment of complex regional pain syndrome. J Int Med Res. 2004; 32: 258-62. Lead author's e-mail: Three-part clinical question For patients with early post-traumatic CRPS, does hyperbaric oxygenation result in a reduction in the severity of symptoms and signs of the syndrome? Search terms Hyperbaric oxygenation, complex regional pain syndrome, reflex sympathetic dystrophy The study Double-blind, concealed and randomised controlled trial with intention to treat. The study patients Diagnosed with CRPS about 1.5 months after trauma to upper limb and had not received prior treatment for CRPS. CONTROL GROUP (N = 34; 34 analysed) Air at 2.4 ATA for 90 minutes daily for 15 sessions over three weeks, plus paracetamol 500 mg three times daily. EXPERIMENTAL GROUP (N = 37; 37 analysed) As above, but breathing 100% oxygen at 2.4 ATA. Th evidence See Table 1. Comments 1 All patients were probably young and relatively fit at entry because the trial was recruited at a military hospital. 2 The HBOT was given prior to other therapy and immediately on diagnosis (1.5 months after injury). This trial therefore measures response of CRPS at an early stage. 3 We have assumed all patients had CRPS affecting the hand. 4 There is no measure of the functional significance of these changes. It is not clear what the significance of 2 units of the VAS is, for example. 5 Patients did appear well matched for severity prior to therapy. 6 We have assumed no losses to follow up, but not specifically stated in the paper. 7 No mention of any confounders considered except age. Appraised by Dr Michael H Bennett Department of Diving and Hyperbaric Medicine Prince of Wales Hospital Randwick, NSW 2031 Australia E-mail: Appraised Wednesday 21 December 2005 Key words Critical appraisal, hyperbaric oxygen therapy, pain, vasoconstriction Table 1 Major outcomes in randomised study of hyperbaric oxygen for early complex regional pain syndrome Outcome at day 45; Air group mean (SD), HBOT group mean (SD), Difference, 95%CI, Visual analogue scale for pain (0 to 10 scale); 5.61 (1.37), 3.72 (1.42), 1.89, 1.23 to 2.55 Wrist flexion (degrees) 44.55 (16.11), 59.86 (17.38), -15.31, -23.26 to -7.36 Wrist circumference (cm), 18.2 (0.72), 16.98 (0.71), 1.22 0.88 to 1.56
Article – 9- Crush injury and other acute traumatic ischaemias
Title: Effects of hyperbaric oxygen therapy on perfusion parameters and transcutaneous oxygen measurements in patients with intramedullary nailed tibial shaft fractures
Authors: Lindstrom, T; Gullichsen, E; Lertola, K; Niinikoski, J
Digital Object Identifier (or PMID etc): PMID: 9670433
Keywords: Nil
Abstract: We evaluated the effect of hyperbaric oxygen (HBO2) therapy on tibialis posterior (TPA), dorsalis pedis (DPA), and sum (TPA + DPA) arterial peak signals, as well as transcutaneous oxygen (PtcO2) tension and leg skin temperature (T) after intramedullary nailing of tibial shaft fractures. Twenty consecutive patients with closed and simple tibial shaft fractures treated with reamed intramedullary nailing were assigned randomly to HBO2 or control groups. HBO2 therapy was given postoperatively at 2.5 atm abs pressure for 90 min daily for a total of five treatments. The first HBO2 therapy was given 1 h after the operation. In both groups, measurements were performed preoperatively, 30 min and 6 h postoperatively, and on the following 5 days. There was a statistically significant improvement in TPA values in the nailed legs in the HBO2 treatment group after the first postoperative day, and these values remained at a significantly higher level until the end of the study when compared to the nailed legs in the control group. Further, there was a statistically significant improvement in PtcO2 values in the nailed legs in the HBO2 group after the third HBO2 treatment. However, there were no statistically significant differences in DPA and TPA + DPA values within or between the nailed legs in HBO2 and control groups. HBO2 therapy seemed to decrease the skin temperature of the nailed legs, but this alteration was not statistically significant. In addition to the clearly documented advantages in the management of crush injuries and compartment syndromes, HBO2 therapy has a positive effect on the perfusion parameter (TPA) and PtcO2 in patients with low energy, intramedullary nailed simple tibial shaft fractures.
Conclusion: The improvement in TPA and PtcO2 values may result from the vasoconstrictive and edema reductive effect on HBO2 with concomitant inhibition of inflammatory reactions with slight cooling.
Article – 10 - Crush injury and other acute traumatic ischaemias
Title: Controversial issues in hyperbaric oxygen therapy: a European College of Hyperbaric Medicine Workshop.
Authors: Kot, J; Mathieu, D
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Keywords: Nil
Abstract: Every few years, the European Committee for Hyperbaric Medicine (ECHM) publishes its recommendations concerning the clinical indications for hyperbaric oxygen therapy (HBOT). The last recommendations were issued during the 7th European Consensus Conference on Hyperbaric Medicine in 2004. Since then, several publications have reported on the use of HBOT in some indications in which it has not yet been recommended routinely, namely aseptic bone necrosis, global brain ischaemia and autism. Patients or their families push physicians and staff of hyperbaric facilities to use hyperbaric treatment regardless of the quality of the scientific evidence. Therefore, the ECHM Workshop "Controversial issues in hyperbaric oxygen therapy" was convened as a satellite meeting of the 2010 European Underwater and Baromedical Society Annual Scientific Meeting in Istanbul, Turkey in 2010. For each topic, a set procedure was used: first came a general report by specialists in the topic, incorporating a review of current pathophysiological, experimental and clinical evidence. Then, there were reports from hyperbaric facilities that had gained clinical experience in that condition, followed by a general discussion with specialists present in the audience. Finally, statements regarding each topic were proposed and voted on by the audience and these were presented to the ECHM Executive Board for consideration and possible approval.
Conclusion: In conclusion, the use of HBOT in femoral head necrosis will be proposed during the next ECHM Consensus Conference to become an 'accepted' indication; whilst the use of HBOT in global brain ischaemia and autism should retain its current ECHM recommendations, that it should be 'optional' and 'non-accepted' respectively.