scubadoc Ten Foot Stop

August 27, 2008

A New Kind of Barotrauma

Filed under: Uncategorizedscubadoc @ 2:30 pm

Bats killed by pressure change - not the blades at wind farms

Based on an article by David Biello in Scientific American

Scientists have known since 2004 that wind farms kill bats, just as they kill birds, even though the sonar of the flying mammals should be able to avoid them. An examination of 188 hoary and silver-haired bats killed at a wind farm in southwestern Alberta in Canada between July and September in 2007 showed that nearly half showed no external injuries—as would be expected if the giant blades had smashed the flying mammals to the ground.

Instead, 90 percent of the 75 bats the researchers ultimately dissected had been killed by burst blood vessels in their lungs, according to results presented in Current Biology—suggesting that the air pressure difference created by the spinning windmills had terminated them, not contact with the blades.

“As turbine height increases, bat deaths increase exponentially,” says ecologist Erin Baerwald of the University of Calgary in Alberta, who led research into the deaths as part of her master’s project. “What we found is a lot of internal hemorrhaging.”

As the wind moves through a wind turbine’s blades, pressure drops behind them by five to 10 kilopascals (a pascal is a unit of pressure), and any bat unlucky enough to blunder into such an undetectable low pressure zone would find its lungs and blood vessels rapidly expanding and, quickly, bursting under the new conditions.

The Summerview wind farm, which Baerwald studied, kills hundreds of bats every year, particularly during the fall migration period that has just begun. But bats that find their way via sonar should have no trouble detecting fast-moving objects like the 200-foot- (60-meter-) long blades on the 300-foot- (90-meter-) tall turbines that spin as quickly as 160 miles (255 kilometers) per hour. And before the installation of these new, taller turbines bat kills had been practically nonexistent.

Pressure drops of as low as 4.4 kilopascals kill common lab rats and all the bats autopsied showed internal damage and bleeding consistent with this type of death, known as barotrauma. “If bats have a lungful of air as they fly through the air-pressure change, there’s nowhere for the air to go,” Baerwald explains. “The small blood vessels around the lungs burst and fill the lungs with fluid and blood.”

This may also explain why, although some birds are killed by wind farms, the majority of casualties are bats. Birds’ lungs are much more rigid and their capillaries are stronger, making them capable of withstanding extreme pressure changes, according to Baerwald. Those birds that are killed typically show damage from being struck by the actual turbine blade. “This offers an explanation of why bats, once they come across these turbines, are so likely to end up dead,” says research biologist Paul Cryan of the U.S. Geological Survey, who has studied the issue but was not involved in this study. But “we don’t have a satisfying explanation for why we’re seeing such large numbers of bats. It seems they’re being attracted to turbines.”

Boyle’s Law strikes again.


Recent HBOT Research Abstracts

Filed under: Publicationscubadoc @ 10:22 am

A proposal of multiplace hyperbaric chamber for animal experimentation and veterinary use.

Rech FV, Fagundes DJ, Hermanson R, Rivoire HC, Fagundes AL.

Integrate Regional University of Alto Uruguai and Missoes, Erechim, RS, Brazil.

Acta Cir Bras. 2008 Aug;23(4):384- 390.

PURPOSE: To develop a project of hyperbaric chamber that allows its safe and reliable use in veterinary and animal experimentation.

METHODS: Based on the technical specifications for the construction of hyperbaric chambers for human beings, it has been developed a design of a chamber with dimensions and characteristics for the use of a midsize animal, (dog or pig), as well as a multiple chamber for the use in small animals (mice, rats, hamsters, rabbits or cats). The technical specifications allowed that the chamber could be used both for veterinary use and for use in experiments on Health Sciences.

RESULTS: A chamber with the following characteristics was built: ASTM A36 steel for the manufacture of the master cylinder and rear cover; front door built in 5052 aluminum; internal diameter of 50.5 cm and 83.0 cm in length; weight 160Kg and internal area of 150cm(3); internal space to accommodate 2 acrylic baskets; 150mm high, 280mm wide and 690mm in length. It was capable of supporting a maximum of hydrostatic pressure test of 3.0 to 4.0 BAR ACT and maximum working pressure of 2.0 BAR or 3.0 ACT; equipped with security devices and valves that triggers with load of 2.2 BAR or 3.2 ACT. Tests for engineering and biological use on animals showed the effectiveness of the device.

CONCLUSION: The development of the project enabled the construction of a hyperbaric chamber with security features and reliability comparable to those required by the legal and technical specifications of a hyperbaric chamber human use.


Barotraumatic orbital emphysema of rhinogenic origin in a breath-hold diver: a case report.

Bolognini A, Delehaye E, Cau M, Cosso L.

Sardinian Institute of Hyperbaric and Subaquatic Medicine, Sassari, Italy.

Undersea Hyperb Med. 2008 May-Jun;35(3) :163-7.

Orbital emphysema is a well-recognized complication of fractures involving the orbit. Commonly, it occurs when high pressure develops in nasal cavity as during nose blowing, coughing or Valsalva’s maneuver and usually occurs in the subcutaneous tissues. We report the case of a young breath-hold diver who developed spontaneous, non compressive orbital emphysema during underwater fishing, with a maximal depth of 25-30 meters in the Sardinian sea. He was otherwise healthy, without previous cranio-facial trauma and nasosinusal diseases or surgery were not present in the history. When he was referred to our attention the patient presented right eyelid ptosis but diplopia and vision impairment were absent. Computer tomography scans showed subcutaneous air in the right upper eyelid and around the eyeball, particularly near the orbit’s roof but optic nerve area, intraconal, was free of air. A dehiscence in lamina papyracea was evident. In our opinion, this has been the point of air entry into the orbit. A supportive therapy was advised and two weeks later the emphysema was recovered completely and the subject was symptoms free. The literature has been revised and to our knowledge no previous cases of barotraumatic orbital emphysema, in a breath-hold diver, are referred.


Bioengineered alternative tissues and hyperbaric oxygen in lower extremity wound healing.
MED 08-42 200717613390 NDN- 230-0824-2194-5

AUTHORS- Kim, Paul J; Heilala, Matt; Steinberg, John S; Weinraub, Glenn M

JOURNAL NAME- Clin Podiatr Med Surg
PP 529-46, x
DOCUMENT TYPE- Journal Article
ISSN- 0891-8422
CORPORATE AUTHOR- Foot and Ankle Institute, 918 Congress Avenue Ste 200, Austin, TX 78701, USA.

With the advent and clinical application of recombinant chemical and cellular mediators of wound healing and a better understanding of the importance of serial debridement, most foot wounds can be healed with little morbidity. Despite these advances, there remains the recalcitrant wound for which more heroic efforts seem warranted. For these patients, advanced wound healing technologies, orthobiologics, and bioengineered alternative tissues may tilt the scales in the direction of definitive wound closure.


Cerebral air embolism treated with hyperbaric oxygen therapy following percutaneous transthoracic computed tomography-guided needle biopsy of the lung.
MED 08-44 200818677615 NDN- 230-0830-9018-6

AUTHORS- Tomabechi, Makiko; Kato, Kenichi; Sone, Miyuki; Ehara, Shigeru; Sekimura, Kenshi; Kizawa, Tetsuya; Kin, Masakado

PP 379-83
DOCUMENT TYPE- Journal Article
ISSN- 0288-2043
CORPORATE AUTHOR- Department of Radiology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka 020-8505, Japan.

A 71-year-old man presented with cough and sputum for 12 months. Chest radiography showed a homogeneous opacity in the right lower lobe. Computed tomography (CT) showed a nodular opacity, 2 cm in diameter, in the posterior segment of the right lower lobe. Mild emphysematous changes were also seen. With the patient in a prone position, a 19-gauge 7.8-cm introducer was placed in the lesion during a single inspiratory breath-hold. A coaxial 20-gauge automated needle was inserted through the introducer using a biopsy gun. Although the patient did not complain of any symptoms, postbiopsy CT showed air in the left ventricle and ascending aorta. After 5 h of bed rest, we found weakness in his left lower extremity. He was transferred to a hyperbaric oxygen chamber and recovered the next day. Air embolism is a rare, potentially fatal complication of percutaneous lung biopsy. Although the true effect of hyperbaric oxygen therapy is controversial, knowledge regarding the prompt management of such cases may help radiologists who perform this procedure.


Effect of hyperbaric oxygen on acute graft-versus-host disease after allogeneic bone marrow transplantation.
MED 08-44 200818549642 NDN- 230-0830-8086-4

AUTHORS- Song, Xiao-Yu; Sun, Lu-Ning; Zheng, Ning-Ning; Zhang, Hai-Peng

JOURNAL NAME- Zhongguo Shi Yan Xue Ye Xue Za Zhi
PP 623-6
DOCUMENT TYPE- Journal Article
JOURNAL CODE- 101084424
ISSN- 1009-2137
CORPORATE AUTHOR- Department of Pathophysiology, College of Basic Medical Sciences, China Medical University, Shenyang 110001, Liaoning Province, China.

The objective of this study was to investigate the function and mechanism of hyperbaric oxygen (HBO) in antagonizing acute graft-versus-host disease (aGVHD) and improving the rate of survival. The lethally irradiated C57BL/6 recipients were injected with bone marrow and lymphocyte of spleen from BALB/c donors and were treated with HBO, cyclosporine A (CsA) and methotrexate (MTX). T lymphocytes and subsets, adhesion molecules and cytokines were detected by flow cytometry, ELISA and RT-PCR respectively. The results showed that the survival rate in HBO group was much higher than that in allogenetic bone marrow transplantation (allo-BMT) group and CsA + MTX group; the numbers of CD3(+), CD4(+), CD8(+), CD4(+)CD11a(+), CD4(+)CD18(+), CD8(+)CD11a(+), CD8(+)CD18(+) lymphocytes in spleen were decreased markedly by HBO and CsA + MTX (p < 0.05); the levels of IL-2 and TNFalpha mRNA and their serum concentrations in HBO group were much lower than those in allo-BMT group but were higher than those in CsA + MTX group; the levels of IL-4 and IL-10 mRNA in HBO group were much higher than those in allo-BMT group and CsA + MTX group. It is concluded that HBO has more remarkable advantage in improving the rate of survival than CsA + MTX, its mechanism of anti-aGVHD is tightly correlated with the transform of T cell and its subsets and the expression of adhesion molecules and cytokines.


Effect of hyperbaric oxygen on patients with traumatic brain injury.

Lin JW, Tsai JT, Lee LM, Lin CM, Hung CC, Hung KS, Chen WY, Wei L, Ko CP, Su YK, Chiu WT.

Department of Neurosurgery, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan.

Acta Neurochir Suppl. 2008;101:145- 9

Hyperbaric oxygen therapy (HBOT) is the medical therapeutic use of oxygen at a higher atmospheric pressure. The United States Food and Drug Administration have approved several clinical applications for HBOT, but HBOT in traumatic brain injury (TBI) patients has still remained in controversial. The purpose of our study is to evaluate the benefit of HBOT on the prognosis of subacute TBI patients. We prospectively enrolled 44 patients with TBI from November 1, 2004 to October 31, 2005. The study group randomly included 22 patients who received HBOT after the patients’ condition stabilization, and the other 22 corresponding condition patients were assigned into the matched control group who were not treated with HBOT. The clinical conditions of the patients were evaluated with the Glasgow Coma Scale (GCS) and Glasgow Outcome Scale (GOS) before and 3 to 6 months after HBOT. The GCS of the HBOT group was improved from 11.1 to 13.5 in average, and from 10.4 to 11.5 (p < 0.05) for control group. Among those patients with GOS = 4 before the HBOT, significant GOS improvement was observed in the HBOT group 6 months after HBOT. Based on this study, HBOT can provide some benefits for the subacute TBI patients with minimal adverse side effects.


Effects of hyperbaric oxygen therapy on facial nerve regeneration.

Vilela DS, Lazarini PR, Da Silva CF.

Otorhinolaryngology Department, Santa Casa Sao Paulo, Faculty of Medical Sciences, Sao Paulo, Brazil.

Acta Otolaryngol. 2008 Mar 10;:1-5 [Epub ahead of print]

Conclusion. Hyperbaric oxygen treatment (HBOT) promoted an increase of the mean axonal diameter in the group evaluated 2 weeks after lesion induction, which suggests a more advanced regeneration process. However, the number of myelin nerve fibers of the facial nerve of the rabbits was similar when compared to the control and treatment groups, in both evaluation periods.

Objective. To evaluate the effect of HBOT on the histological pattern of the facial nerve in rabbits exposed to a nerve crush injury. Materials and methods. Twenty rabbits were exposed to facial nerve crush injury. Ten rabbits received HBOT, 10 rabbits comprised the control group. The rabbits were sacrificed 2 and 4 weeks after the trauma. Qualitative morphological analysis, measurement of the external axonal diameters and myelin fiber count were carried out in an area of 185 000 microm(2). Results. There was an increase in the area of the axons and thicker myelin in the 2 weeks treatment group in comparison with the control group. The mean diameter of the axons was of 2.34 microm in the control group and of 2.81 microm in the HBOT group, with statistically significant differences. The 2 week control group had a mean number of myelin fibers of 1865.2+/-664, and the HBOT group had a mean number of 2026.3+/-302; this was not statistically significant. The 4 week control group presented a mean of 2495.1+/-479 fibers and the HBOT group presented a mean of 2359.9+/-473; this was not statistically significant.


Effects of Hyperbaric Oxygen Therapy on Wound Healing After Tracheal Resection and End-to-End Anastomoses in Rats: Results of Early Observations.
MED 08-43 200818704859 NDN- 230-0829-2644-8

AUTHORS- Gorur, R; Hahoglu, A; Uzun, G; Kutlu, A; Turut, H; Yiyit, N; Candas, F; Isitmangil, T

JOURNAL NAME- Thorac Cardiovasc Surg
PP 359-62
DOCUMENT TYPE- Journal Article
ISSN- 0171-6425
CORPORATE AUTHOR- Department of Thoracic Surgery, GATA Haydarpasa Teaching Hospital, Istanbul, Turkey.

BACKGROUND: Proliferating scar tissue is an important problem after tracheal surgery. Hyperbaric oxygen (HBO) provides good support to the poorly perfused tissues. We aimed to evaluate the early effects of HBO therapy on tracheal healing after tracheal resection.

METHODS: A total of 15 Wistar rats were divided into two groups and two tracheal rings of each rat were resected. A control group received no therapy while the other group was treated with HBO. At the end of the study or when a rat died, a histopathological examination was performed to assess neovascularization, necrosis and epithelization.

RESULTS: HBO treatment caused better epithelization and inflammation scores compared to the control group. In the HBO group the intraluminal purulent exudates were limited ( P = 0.001). Healing of the damaged mucosal epithelium was better in the HBO group ( P = 0.031). In the HBO-treated group, neovascularization also started earlier than in the group without HBO. CONCLUSION: Our short-term observation results demonstrate that HBO treatment increases tracheal healing and decreases the complication ratios. HBO may be preferred as a supportive treatment modality during the healing period after tracheal surgery.


Effects of pressure, cold and gloves on hand skin temperature and manual performance of divers.
MED 08-44 200818369658 NDN- 230-0830-6562-6

AUTHORS- Zander, Joanna; Morrison, James

JOURNAL NAME- Eur J Appl Physiol
PP 237-44
DOCUMENT TYPE- Journal Article
JOURNAL CODE- 100954790
ISSN- 1439-6319
CORPORATE AUTHOR- School of Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada.

Cold water immersion and protective gloves are associated with decreased manual performance. Although neoprene gloves slow hand cooling, there is little information on whether they provide sufficient protection when diving in cold water. Nine divers wearing three-fingered neoprene gloves and dry suits were immersed in water at 25 and 4 degrees C, at depths of 0.4 msw (101 kPa altitude adjusted) and 40 msw (497 kPa) in a hyperbaric chamber Skin temperatures were measured at the fingers, hand, forearm, chest and head. Grip strength, tactile sensitivity and manual dexterity were measured at three time intervals. There was an exponential decay in finger and back of hand skin temperatures with exposure time in 4 degrees C water. Finger and back of hand skin temperatures were lower at 40 msw than at 0.4 msw (P < 0.05). There was no effect of pressure or temperature on grip strength. Tactile sensitivity decreased linearly with finger skin temperature at both pressures. Manual dexterity was not affected by finger skin temperature at 0.4 msw, but decreased with fall in finger skin temperature at 40 msw. Results show that neoprene gloves do not provide adequate thermal protection in 4 degrees C water and that impairment of manual performance is dependent on the type of task, depth and exposure time.


Hyperbaric oxygen therapy aggravates liver reperfusion injury in rats.

Lima CX, Sanches MD, Rezende Neto JB, Silva RC, Teixeira MM, Souza DD, Santos GD, Melo JR.

Department of Physiology, School of Science, Federal University of Minas Gerais, Brazil.

Acta Cir Bras. 2008 Aug;23(4):315- 321

PURPOSE: To evaluate the effects of hyperbaric oxygen (HO) therapy in the protection against liver ischemia/reperfusion injury.

METHODS: Thirty-two male Wistar rats were divided into four groups of eight animals each: group A - laparotomy and liver manipulation, group B - liver ischemia and reperfusion, group C - HO pretreatment for 60 min followed by liver ischemia and reperfusion, and group D - pretreatment with ambient air at 2.5 absolute atmospheres for 60 min followed by liver ischemia and reperfusion. Plasma was assayed for aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH). Intra-arterial blood pressure was monitored continuously. Myeloperoxidase activity in the liver and lung was assessed 30 min after reperfusion.

RESULTS: Plasma AST, ALT and LDH increased after reperfusion in all animals. Plasma ALT values and myeloperoxidase activity in the liver parenchyma were higher in HO-pretreated animals than in groups A, B and D. HO had a negative hemodynamic effect during liver reperfusion.

CONCLUSION: Liver preconditioning with hyperbaric oxygen therapy aggravated liver ischemia/reperfusion injury in rats as demonstrated by plasma ALT and liver myeloperoxidase activity.


Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis.

Yoshida T, Kawashima A, Ujike T, Uemura M, Nishimura K, Miyoshi S.

The Department of Urology, Osaka Rosai Hospital, and The Department of Urology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.

Int J Urol. 2008 Jul;15(7):639- 41

Hyperbaric oxygen (HBO) therapy has recently emerged as a potential primary option for the management of hemorrhagic cystitis. We review our experience treating hemorrhagic cystitis with HBO. Between January 2001 and May 2007, eight patients with radiation-induced hemorrhagic cystitis underwent HBO therapy. There were five men and three women with a mean age of 64.3 years (47-73). Radiation was given for local disease, and the mean dosage delivered was 56.6 Gy (42-70). The mean duration between the onset of hematuria and the beginning of HBO therapy was 8.9 months (3-34). Mean follow-up period was 15.5 months (2-31). Hematuria resolved completely in six of the eight patients, one of whom suffered recurrence of hematuria and was treated with HBO until the hematuria resolved again. The response rate was 75%, compatible with the previous reports, and no side-effects of HBO were noted. HBO treatment should be attempted for radiation-induced hemorrhagic cystitis.


Hyperbaric oxygenation for tumour sensitisation to radiotherapy: A systematic review of randomised controlled trials.

Bennett M, Feldmeier J, Smee R, Milross C.

Department of Diving and Hyperbaric Medicine, Prince of Wales Hospital, University of NSW, Randwick, NSW 2031, Australia.

Cancer Treat Rev. 2008 Jul 18;

BACKGROUND: Radiotherapy is a well-established treatment for some solid tumours. Hyperbaric oxygenation (HBO) may improve radiotherapeutic killing of hypoxic cancer cells, so the simultaneous administration of radiotherapy and HBO may reduce mortality and tumour recurrence.

METHODS: We performed a systematic search of the literature in September 2007 for randomised controlled trials, and made pooled analyses of pre-determined clinical outcomes.

RESULTS: Nineteen trials contributed to this review (2286 patients). There was a reduction in mortality for head and neck cancers at one and five years after therapy (at five years RR 0.82, P=0.03, NNT=5), and improved local tumour control at three months (RR 0.58, P=0.006, NNT=7). Any advantage is achieved at the cost of an increased rate of both severe radiation tissue injury (RR 2.35, P<0.0001, NNH=8) and the chance of seizures during therapy (RR 6.76, P=0.03, NNH=22).

CONCLUSIONS: There is some evidence that HBO improves local tumour control and mortality for cancers of the head and neck, and local tumour recurrence in cancers of the uterine cervix. These benefits may only occur with unusual fractionation schemes. HBO is associated with significant adverse effects including oxygen toxic seizures and severe radiation tissue injury. The methodological and reporting inadequacies of the studies included in this review demand a cautious interpretation. More research is needed for head, neck and uterine cervical cancer, but is probably not justified for bladder cancer. There is little evidence available concerning malignancies at other sites.


Hyperbaric oxygen therapy in BKV-associated hemorrhagic cystitis refractory to intravenous and intravesical cidofovir: Case report and review of literature.

Focosi D, Maggi F, Pistolesi D, Benedetti E, Papineschi F, Galimberti S, Ceccherini-Nelli L, Petrini M.

Division of Hematology, Department of Oncology, Transplantations and New Technologies in Medicine, University of Pisa, Italy.

Leuk Res. 2008 Jul 23; [Epub ahead of print]

Hemorrhagic cystitis is a common complication in hematopoietic stem cell transplant recipients. We report here a case of severe BKV-associated hemorrhagic cystitis who did not respond to intravenous cidofovir. Overt hematuria successfully resolved after a few days on hyperbaric oxygen and intravesical instillations of cidofovir, while BK viruria dropped after a few weeks and remained low. We review the literature for therapeutic options in hemorrhagic cystitis and try to explain how hyperbaric oxygen stimulates mucosal repair in the urinary bladder.


Hyperbaric oxygen preconditioning promotes angiogenesis in rat liver after partial hepatectomy.

Ren P, Kang Z, Gu G, Liu Y, Xu W, Tao H, Zhang JH, Sun X, Ji H.

Department of Pharmacology, China Pharmaceutical University, Nanjing, 210009, PR China.

Life Sci. 2008 Jun 24; [Epub ahead of print]

Hyperbaric oxygen preconditioning (HBO-PC) increases the level of HIF-1alpha (hypoxia inducible factor-1alpha) and its target gene VEGF (vascular endothelial growth factor) which is involved in angiogenesis. Liver regeneration is an angiogenesis- dependent process. We hypothesized that HIF-1alpha and VEGF mediated the angiogenesis effect of HBO-PC on regenerating rat liver. Male Sprague Dawley rats received HBO-PC followed by 70% partial hepatectomy. Proliferation of hepatocytes and endothelial cells was evaluated by BrdU (bromodeoxyuridine) staining. Microvascular density was assessed by immunohistochemistr y. mRNA expression of HIF-1alpha was assessed by quantitative RT-PCR and protein levels of HIF-1alpha and VEGF were assessed by western blot. HIF-1alpha DNA-binding activity was determined with an ELISA-based kit. HBO-PC increased the proliferation index of endothelial cells and microvascular density at 48 h after partial hepatectomy. The protein level and DNA-binding activity of HIF-1alpha and the protein level of VEGF were increased by HBO-PC before and after partial hepatectomy. Partial hepatectomy alone also increased proliferation index and the expressions of HIF-1alpha and VEGF. Our results indicated that the angiogenesis effect of HBO-PC on liver after partial hepatectomy could be achieved by increased HIF-1alpha activity and VEGF expression. However, the angiogenic effect of HBO-PC is moderate and HBO-PC failed to produce additional effect on the enhancement of HIF-1alpha and VEGF induced by partial hepatectomy alone.


Hyperbaric oxygen therapy seems to enhance recovery from acute acoustic trauma.

Ylikoski J, Mrena R, Makitie A, Kuokkanen J, Pirvola U, Savolainen S.

Helsinki Ear Institute and Department of Otolaryngology and Institute of Biotechnology, University of Helsinki, and Centre for Military Medicine, Helsinki, Finland.

Acta Otolaryngol. 2008 Apr 1;:1-7 [Epub ahead of print]

Conclusion. The average recovery of hearing and cessation of tinnitus was significantly better after hyperbaric oxygen therapy (HBOT) than after normobaric oxygen therapy (NBOT). HBOT can be valuable adjuvant therapy for patients with acute acoustic trauma (AAT). Objectives. AAT was one of the early indications for the use of HBOT. The rationale of administering oxygen to patients with AAT is based on experimental studies showing that noise exposure results in cochlear hypoxia, which could be compensated by HBOT. The aim of this study was to investigate the efficacy of HBOT in patients with AAT. Patients and methods. We compared the recovery from hearing impairment and tinnitus in 60 ears treated with HBOT with 60 ears treated with NBOT. The HBOT was given daily for 1-8 days. There were no significant differences in clinical or audiological data between HBOT and NBOT groups. Results. The average recovery of hearing both at high and speech frequencies was significantly better and tinnitus persisted less commonly after the HBOT than after the NBOT. Normal hearing at the end of the follow-up period was regained in 42 ears in the HBOT group and in 24 ears in the NBOT group (p<0.01).


Hyperbaric oxygen therapy as a prophylactic and treatment against ileus and recurrent intestinal obstruction soon after surgery to relieve adhesive intestinal obstruction.
MED 08-43 200817593223 NDN- 230-0828-2854-5

AUTHORS- Ambiru, Satoshi; Furuyama, Nobuaki; Kimura, Fumio; Shimizu, Hiroaki; Yoshidome, Hiroyuki; Miyazaki, Masaru; Shimada, Hideaki; Ochiai, Takenori

JOURNAL NAME- J Gastroenterol Hepatol
PP e379-83
DOCUMENT TYPE- Journal Article
ISSN- 1440-1746
CORPORATE AUTHOR- Departments of General Surgery, Surgical Center, Chiba University Hospital, Chiba University Graduate School of Medicine, Chiba, Japan.

BACKGROUND AND AIM: Nonoperative management of cases of adhesive intestinal obstruction would be ideal, especially for patients who have recently undergone surgery to relieve the same condition. We aimed to examine whether hyperbaric oxygen (HBO) therapy might have therapeutic potential for the treatment of postoperative paralytic ileus and recurrent adhesive intestinal obstruction soon after surgery, to relieve adhesive intestinal obstruction, because of its unique mechanisms in these contexts.

METHODS: A total of 133 patients were enrolled in the present study. We examined non-per os periods, hospital stay, and clinical course according to the postoperative course of the 133 patients. RESULTS: After surgical intervention, 75 patients left the hospital without morbidity. Nineteen patients were successfully administered prophylactic HBO therapy to facilitate intestinal motility and to prevent paralytic ileus. The remaining 39 patients suffered from postoperative paralytic ileus or early recurrence of obstruction during the same hospitalization period. The patients who underwent prophylactic HBO therapy had significantly shorter non-per os periods and hospital stays after surgery than those who were not initially given HBO therapy (P < 0.05). Similarly, there were significant differences in duration of hospital stay after surgery between patients with HBO therapy as treatment and those who received other conservative therapies (P < 0.05).

CONCLUSIONS: HBO therapy may have a prophylactic effect on postoperative paralytic ileus and may be of therapeutic benefit in the management of early recurrent adhesive intestinal obstruction following surgery to relieve adhesive intestinal obstruction.


Hyperbaric oxygen induces placental growth factor expression in bone marrow-derived mesenchymal stem cells.
MED 08-44 200818558410 NDN- 230-0830-8270-4

AUTHORS- Shyu, Kou-Gi; Hung, Huei-Fong; Wang, Bao-Wei; Chang, Hang

PP 65-73
DOCUMENT TYPE- Journal Article; Research Support, Non-U.S. Gov’t
ISSN- 0024-3205
CORPORATE AUTHOR- Division of Cardiology, Shin Kong Wu Ho-Su Memorial Hospital, and Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.

The bone marrow is home to mesenchymal stem cells (MSCs) that are able to differentiate into many different cell types. The effect of hyperbaric oxygen (HBO) on MSCs is poorly understood. Placental growth factor (PlGF) is an attractive therapeutic agent for stimulating revascularization of ischemic tissue. HBO has been shown to improve diabetic wound healing by increase circulating stem cells. We hypothesized that HBO induces PlGF expression in bone marrow-derived MSCs. The MSCs were obtained from adult human bone marrow and expanded in vitro. The purity and characteristics of MSCs were identified by flow cytometry and immunophenotyping. HBO at 2.5 ATA (atmosphere absolute) significantly increased PlGF protein and mRNA expression. The induction of PlGF protein by HBO was significantly blocked by the addition of N-acetylcysteine, while wortmannin, PD98059, SP600125 and SB203580 had no effect on PlGF protein expression. However, the specific inhibitor of nitric oxide synthase, L-NAME did not alter the PlGF protein expression induced by HBO. HBO significantly increased the reactive oxygen species production and pretreatment with N-acetylcysteine significantly blocked the induction of reactive oxygen species by HBO. HBO significantly increased the migration and tube formation of MSCs and pretreatment with N-acetylcysteine and PlGF siRNA significantly blocked the induction of migration and tube formation by HBO. In conclusion, HBO induced the expression of PlGF in human bone marrow-derived MSCs at least through the oxidative stress-related pathways, which may play an important role in HBO-induced vasculogenesis.


Hyperbaric oxygen preconditioning promotes angiogenesis in rat liver after partial hepatectomy.
MED 08-43 200818644387 NDN- 230-0827-2562-6

AUTHORS- Ren, Ping; Kang, Zhiming; Gu, Guojun; Liu, Yun; Xu, Weigang; Tao, Hengyi; Zhang, John H; Sun, Xuejun; Ji, Hui

PP 236-41
DOCUMENT TYPE- Journal Article
ISSN- 0024-3205
CORPORATE AUTHOR- Department of Pharmacology, China Pharmaceutical University, Nanjing, 210009, PR China.

Hyperbaric oxygen preconditioning (HBO-PC) increases the level of HIF-1alpha (hypoxia inducible factor-1alpha) and its target gene VEGF (vascular endothelial growth factor) which is involved in angiogenesis. Liver regeneration is an angiogenesis-dependent process. We hypothesized that HIF-1alpha and VEGF mediated the angiogenesis effect of HBO-PC on regenerating rat liver. Male Sprague Dawley rats received HBO-PC followed by 70% partial hepatectomy. Proliferation of hepatocytes and endothelial cells was evaluated by BrdU (bromodeoxyuridine) staining. Microvascular density was assessed by immunohistochemistry. mRNA expression of HIF-1alpha was assessed by quantitative RT-PCR and protein levels of HIF-1alpha and VEGF were assessed by western blot. HIF-1alpha DNA-binding activity was determined with an ELISA-based kit. HBO-PC increased the proliferation index of endothelial cells and microvascular density at 48 h after partial hepatectomy. The protein level and DNA-binding activity of HIF-1alpha and the protein level of VEGF were increased by HBO-PC before and after partial hepatectomy. Partial hepatectomy alone also increased proliferation index and the expressions of HIF-1alpha and VEGF. Our results indicated that the angiogenesis effect of HBO-PC on liver after partial hepatectomy could be achieved by increased HIF-1alpha activity and VEGF expression. However, the angiogenic effect of HBO-PC is moderate and HBO-PC failed to produce additional effect on the enhancement of HIF-1alpha and VEGF induced by partial hepatectomy alone.


August 26, 2008

2008 Annual Meeting of the Great Lakes Chapter of the UHMS

Filed under: Uncategorizedscubadoc @ 2:50 pm




of the

Undersea & Hyperbaric Medical Society



2008 - 29th Annual Conference


We have again combined forces with THE TORONTO HYPERBARIC MEDICINE SYMPOSIUM to deliver an outstanding 2 day conference in the fields of Diving and Hyperbaric medicine.


Saturday, October 18 — Diving


Saturday: Presentations during this session should be of interest to the recreational diving community, and members of commercial and scientific diving organizations.  Topics will include:

  • Decompression Illness - It isn’t what it used to be…but then, it never was!

  • The 10 minute breath hold - tricks and traps of apnea

  • Improving diver performance

  • First hyperbaric stretcher in Quebec


For more information, please visit our website at:  






 Sunday, October 19 — Hyperbaric


Sunday: This session should be of interest to the medical professional (technologist, nurse and physician).  The scientific symposium will provide an update about current medical knowledge, mechanisms of action and clinical applications in hyperbaric medicine.  Presentations will include new research topics and reviews of clinical hyperbaric medicine.


For more information, please visit THMS website at:





TIME:             Saturday       8:00 - 17:30  Great Lakes Chapter UHMS.  

                       Sunday         8:00 - 17:30  Toronto Hyperbaric Medicine Symposium


COST:           For each of GLC & THMS the cost is $65 and increases by $15 after October 1.

                       Student rate is $50 and there is a two day combined rate of $120.

                       UHN staff have a discounted rate of $25 daily to cover food & refreshments

                       Fees include morning and afternoon refreshments and lunch as well.


Please register online using the University Health Network website  



TORONTO GENERAL HOSPITAL, Residence College Hotel, Unity Hall, Toronto Ontario, Canada


We gratefully acknowledge our sponsors:

Pan-America Hyperbarics, Inc.

Toronto General Hospital

Sechrist Industries, Inc

Oxy-Heal Health Group


OUC - Ontario Underwater Council

Ontario Neurotrauma Association

The University of Toronto

The Ontario Medical Association


August 19, 2008

Navy Carrier Oriskany Article in New York Times

Filed under: Articlescubadoc @ 10:59 am

In the August 18, 2008 New York Times there is an article with a slide show of photographs about the US Navy aircraft carrier, Oriskany. This vesssel was sunk off of Pensacloa Florida as a part of the Navy’s reef program.

The superstructure of the ship is in water shallow enough for recreational divers using compressed air but deeper portions of the vessel are dangerous for sport divers and can pose a risk for decompression sickness in the untrained non-technical diver.

The article can be accessed at this web site:


August 18, 2008

DAN Position Open for Vice President of Medical Services

Filed under: Newsscubadoc @ 9:16 am

Divers Alert Network (DAN)
Position Open for: Vice President of Medical Services

Divers Alert Network (DAN), a non-profit 501(c)(3) dive safety organization, seeks a physician for the position of Vice President of Medical Services. This position is located at DAN Headquarters in Durham, North Carolina. This opportunity includes extensive diving medical consultation; medical program development; risk assessment; oversight, evaluation and quality assurance; supervision of professional staff and functioning as a member of a multidisciplinary senior management team.

This position is responsible for the operation and activities of the DAN Medical Department; provides medical guidance and oversight for the DAN Medical Emergency Hotline, the DAN Medical Information Services (both phone and electronic communication) and works cooperatively with the DAN Medical Consultant to assure necessary compliance with current best diving medical practices.

Position requires an MD or DO degree. Candidate should have received additional specialized training in Diving and Hyperbaric Medicine by way of a recognized Hyperbaric Fellowship, Military training and/or Board certification.

The ideal candidate for this position will possess a working knowledge of diving in all its forms and applications and how these constituencies interact with and support diving medicine and research. This includes but is not limited to recreational, scientific, public safety, commercial and military applications.

Interested and qualified persons contact: Dan Orr, DAN President/CEO or Jeff Myers, DAN VP/COO

Divers Alert Network
6 West Colony Place
Durham, North Carolina 27705
(919) 684-2948


August 8, 2008

Malaria Prevention in Short Term Travelers

Filed under: Article, Publicationscubadoc @ 10:23 am

Malaria continues to be endemic in certain parts of the world and divers need to be properly advised as to the preventive and therapeutic measures that need to be considered when planning a trip into the malaria endangered zone.

In this week’s New England Journal of Medicine there is a vignette about a family planning a trip to Africa that is most informative and answers many questions that are often posed.

See .


August 6, 2008

UHMS Mid-West Chapter: 2008 Hyperbaric Medicine Update: Sept 26-27, 2008: Sherrodsville OH

Filed under: Newsscubadoc @ 10:17 am




Atwood Lake Resort & Conference Center
Sherrodsville, Ohio

Sponsored by:
 Mid-West Chapter of UHMS
Mercy Medical Center, Canton, Ohio


August 5, 2008

Undercurrent Online Update

Filed under: Article, News, Publicationscubadoc @ 9:10 am

U N D E R C U R R E N T   O N L I N E   U P D A T E
F O R   N O N - S U B S C R I B E R S

Undercurrent — Consumer Reporting for
the Scuba Diving Community since 1975

Dive News

August 5, 2008

You have received this message because you have signed up on our website to receive this email or you are a former subscriber or Online Member of Undercurrent . Removal instructions are below.

Australia Says Dive Boat to Blame for Abandoning Divers: In our July issue, divers Allyson Dalton and Richard Neely gave us their account of being adrift for 19 hours on the Great Barrier Reef after their dive boat, the Pacific Star, failed to pick them up (Online Members can read the story at Undercurrent in our “Back Issues” section). OzSail, which operates the Pacific Star, publicly tried to discredit the divers and blame them for disobeying rules. Now the Queensland government is about to release a report stating the mishap was due to operator error. It’s expected to recommend charges against OzSail and the boat’s dive trip director Kylie Irwin, recently fired by OzSail. Penalties include up to six months’ imprisonment, individual fines of $37,500 and a company fine of $187,500.

Great White Shark Cage Diving: Leave from San Diego August 28; Special deal for Undercurrent; Book the Nautilus Explorer’s 6 days/5 nights (4 days of diving) Guadalupe Island great white shark cage diving trip and receive a free stateroom upgrade (space available). Undercurrent readers regularly praise captain Mike Lever and the crew of his 116- foot, 16 passenger modern, comfortable, stabilized liveaboard (they even have 40 micro-brews and 50 different labels of wine) that caters to highly experienced divers, photographers and rebreather divers. Prices start at $2380. If you can’t make this trip, they go north to Alaska and south to see the mantas of Socorro island other times of the year. or email for the special deal.

Ten Year Anniversary Special on Online Membership: Ten years ago we launched Undercurrent Online Membership on our then-new website. As an Online Member, you now have complete access to

To mark this occasion, we’re offering a special introductory price for Online Membership — $29.95/year. This is a ~25% discount off the standard price of $38.95/year. To join simply enter your information, and then you can immediately browse through our 10,000+ pages of reliable diving information from serious divers like yourself. This offer is for a limited time only, so join now.

Coral Spawning Coming up in the Florida Keys: The full moon on August 16 is expected to kick off annual coral mass-spawning rituals. Millions of sperm and eggs will be released into the water to unite at the surface. Branching corals like finger and staghorn typically spawn three to five days after the full moon, two hours after sunset. Star and boulder corals spawn six to eight days after, about three hours after sunset. Marine researchers suggest booking with Florida Keys dive operators for night dives August 19 to 24. One dive shop, Atlantis Dive Center ( in Key Largo, is predicting spawning times at 11:20 p.m. on August 22 and 23, and has set aside two boats for each dive.

Buy the Best Fish ID Books Around: Wherever you dive, you need good ID books for fish and corals. We’ve got the best, covering the Caribbean, Indonesia, Fiji, Hawaii, Mexico and other points. Go to Undercurrent and click on “Diving Books and Guides.” You’ll get the best price has to offer, and our profit will go to save those fish and coral reefs you’ll be reading about on your next trip.

Dive Instructor Charged With Homicide: Dive instructors do make mistakes, but rarely do they lead to murder charges. But in this unfortunate case, Allison Rainey Gibson, a former instructor at the University of Alabama, faces charges of criminally negligent homicide involving the death of her 21-year-old student Zachary Moore in April 2007. Moore’s father is also filing a civil lawsuit against her. It alleges that Gibson, 44, was in charge of a dive training class at the university but was giving a private lesson to someone not enrolled in the class, while her official students were practicing taking off their gear at the bottom of the 18-foot pool. Moore had trouble on the surface after the drill and died; an autopsy showed the cause as barotrauma. More details about this incident in a forthcoming issue.

Why Divers Are Cuckoo for CoCo View: In this month’s free article online, one of our undercover writer reports on “dive camp” at CoCo View in Roatan, and why it’s worth frequent repeat visits. One tip: book way ahead as rooms fill up a year in advance. When you become an Undercurrent subscriber, you’ll get immediate access to reader reviews of the island’s resorts and dive operators in our Instant Reader Reports. There you’ll also find hundreds of reader reviews about dive destinations around the world.

Airlines Alert: Check Your Flight: When you’re flying low-cost airlines, reconfirm your flight. A subscriber purchased tickets to Turks and Caicos for a July trip, and called before departure and learned that Spirit Airlines had rearranged her family’s flights to an earlier one and, they would have to overnight in Atlantic City before flying to Provo, thereby missing a full day of diving. Because Spirit didn’t notify her, the family would have arrived at the airport to find their flight had departed, but luckily they were able to make better arrangements. With airlines like American cutting flights to the Caribbean, stay abreast of your schedule if you have travel plans.

A Bad Economy Means Good Jobs for Divers: The faltering housing market and the soaring price of oil mean more jobs for commercial divers, especially around oil rigs. The Underwater Centre in Fort William, Scotland, expects up to 400 new divers to qualify this year for work in places like the North Sea. There, air divers make $900 a day, while those who must live in decompression chambers can get up to $2,000 a day. The International Diving Schools Association ( has listings for U.S. and international dive training schools.

Protect your SLR camera from housing leaks: Since most housings suspend the camera in the middle of the space on a platform mount, any absorbent material in the housing bottom will capture the water before it reaches the camera. While you can stuff an old sock in your housing, a feminine hygiene pad is more compact and far more absorbent.

For those of you who might have missed our announcement last month: We have launched an exciting, new feature on our website to help serious divers obtain the best, most complete and latest diving information: The Divers’ Forum. This forum offers the thousands of Undercurrent readers a means of directly communicating with each other. You can post questions or replies to others’ questions on virtually any aspect of diving. Unlike other forums, here you interact only with other Undercurrent subscribers and Online Members — as knowledgeable, well traveled, and experienced a group of serious divers as you’ll find anywhere. . . If you are not a current print subscriber or Online Member, you can become one in just a minute and get immediate access to the Forum and thousands of pages of solid dive info — see the offer above. Then log in and join in the dialogue at The Divers’ Forum.

What’s In The August Issue:

Read it online now. In this issue, you’ll find out about:

* CoCo View, a dive camp for hardcore fans in Roatan;
* How to avoid mosquitoes — and malaria — in Roatan and the other Bay Islands;
* Good dive travel deals, like all-inclusive weeks starting at $660;
* What’s going on with The Spirit of Niguini in Papua New Guinea;
* How dive computers are commonly misused;
* How one guy got an electric shock while cave diving;
* Part I of our series on knowing what’s really involved when you sign a dive operator’s liability waiver;
* How you can self-publish your own dive photography book;
* Why it’s a good idea to spend your afterlife underwater;
* Cayman dive operators are protesting a specific safety regulation; and much, much more.

Ben Davison, editor/publisher
Contact Ben


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