Open issues in management of carbon monoxide poisoning in pregnancy: practical suggestions.

Carbon monoxide (CO) poisoning during pregnancy may cause deleterious effects to the fetus. Hyperbaric oxygen therapy (HBO) in pregnancy is proven to be safe and it is considered to be beneficial, reducing the severity of the fetal injuries. However, a number of issues are still to be discussed, among them the question of the carboxyhemoglobin (COHb) levels that trigger HBO therapy in pregnant CO poisoned patients. In this letter we report some practical suggestions for organizations wishing to develop their own protocols.

Evidence-Supported HBO Therapy in Femoral Head Necrosis: A Systematic Review and Meta-Analysis.

Although many studies have shown that hyperbaric oxygen (HBO) therapy can significantly improve symptoms and quality of life of patients affected by femoral head necrosis, this therapy is not worldwide approved yet. This meta-analysis was performed to evaluate its clinical effect. Relevant studies published before May 2020 were systematically searched using terms related to HBO and femoral head necrosis. Fixed and random-effects models were used to estimate the odds ratio (OR) with 95% confidence intervals (CI). Subgroup analyses and publication bias tests were carried out to explore potential study heterogeneity and bias. Ten studies involving 353 controls and 368 HBO-treated cases were included, most of which were conducted on Asian population. The clinical effect in the HBO therapy group was 3.84 times higher than in the control group (OR = 3.84, 95% CI (2.10, 7.02), p < 0.00001). Subgroup analyses showed that the clinical effect of HBO therapy was statistically significant in the Asian subpopulation which represented most of the subjects (OR = 3.53, 95% CI (1.87, 6.64), p < 0.00001), but not in the non-Asian subpopulation, probably because of insufficient numerosity (OR = 7.41, 95% CI (0.73, 75.71), p = 0.09). The results of this meta-analysis suggest that patients with femoral head necrosis treated with HBO therapy can achieve a significant clinical improvement.

Pathophysiological Responses to a Record-Breaking Multi-hour Underwater Endurance Performance: A Case Study.

The "Endless Diving Project-Step 36" took place in the harbor waters of the town of Maratea in Italy in September 2014. The goal of the project was an attempt by an experienced male diver, equipped with a wet 7-mm suit and a normal gas tank, to set the world record-breaking of nonstop underwater performance. We studied inflammatory, hematological, and endocrine responses during the extreme condition of the attempt. Venous blood samples were collected at baseline, the day before the attempt; immediately after the return from underwater; then at Day 1, Day 4, and Day 12; and later at Month 1 and Month 41 of follow-up. We found that there was an increase in the content of blood neutrophils, monocytes, and eosinophils and a decrease in lymphocytes at Day 1 and a late increase in basophils at Day 12 after the dive. Inflammatory markers and hematocrit and hemoglobin increased immediately after the dive, dropped at Day 1, and reverted gradually to the control level from Day 4 to Day 12. Serotonin and dopamine decreased, while adrenaline increased at Day 1, gradually recovering in the days of follow-up. Insulin, luteinizing hormone, growth hormone, and prolactin increased, while testosterone, cortisol, 17ß-estradiol, thyroid-stimulating hormone, and adrenocorticotropic hormone decreased at Day 1, with a partial recovery at Day 4. We conclude that the homeostatic response to the extreme, prolonged underwater performance showed signs of psychological and pro-inflammatory stress. The hormonal response reflected an acute testicular insufficiency. These responses resembled those characteristics for ultra-endurance exercise accompanied by vasculitis and dehydration.

Middle ear barotrauma during hyperbaric oxygen therapy; a review of occurrences in 5,962 patients.

Hyperbaric-associated middle ear barotrauma (MEB) is one of the most common side effects of the exposure to hyperbaric oxygen (HBO2) therapy. This retrospective observational study of 5,962 patients undergoing longterm therapy for chronic conditions took place at the local Diving and Hyperbaric Medicine Unit (DHMU) in Villafranca-Verona (Italy), a DHMU that administers, in multiplace chambers, more than 20,000 HBO2 treatments per year. The study was designed to weight and analyze both the incidence and severity of MEBs at the facility. Thanks to a systematic recording method over eight years, 2003-2010, we observed 549 MEBs (9.2% of all HBO2 treatments). The majority of them were female patients older than 50. MEBs observed were usually of minor complexity, with minimal otoscopic changes (69.03% of our occurrences were registered as Wallace-Teed Grade 1). MEBs were registered in 20.3% of those patients already suffering from difficulties in equalizing ear pressure, and/or presenting ear pain during the initial compression phase (descent) of the hyperbaric treatment. Inflammatory diseases of the upper respiratory tract, with special attention to rhinitis, appear to be a condition capable of predisposing patients in developing MEB. MEB did lead to the suspension of therapy for 89 patients in our case series. This was 16.2% of all the MEBs registered, or 1.49% of all patients who underwent HBO2 at the facility in the considered time lapse.

Review on hyperbaric oxygen treatment in femoral head necrosis.

BACKGROUND: Femoral head necrosis (FHN) is a common invalidating disease with an unclear etiology and pathophysiology that affects middle-aged people. FHN may lead to joint collapse and require invasive treatments. Because of its clinical and socioeconomic significance, an early diagnosis, staging and appropriate treatment are required. Unfortunately, to date a unique algorithm for the treatment of FHN has not been defined. OBJECTIVE: In this report we summarize the Tenth European Consensus Conference on hyperbaric medicine (April 2016, France), during which experts from Europe revised the list of accepted indications for hyperbaric oxygen (HBO2) treatment, including FHN. METHODS: In this report all aspects of osteonecrosis discussed during the meeting have been considered: pathophysiology,clinical presentation, standard management, HBO2 therapy and evidence-based review of its efficacy. All observations are based on a thorough review of the best available research and evidence-based medicine. CONCLUSIONS: The Consensus Conference in Lille established FHN as an indication for HBO2 therapy and suggested a protocols guideline to adopt for this pathology.

HBO2 in snake envenomation (atrox albinus rattlesnake): a case report in a human.

A patient suffered from an envenomation that, at his hospitalization, was judged severe: Grade 3 out of 3, as defined in clinical studies for CroFab™ antidote [Crotalidae Polyvalent Immune Fab (Ovine)]. In addition to the usual antivenom treatment we applied adjunctive hyperbaric oxygen (HBO2) therapy. Our aim was to facilitate better control of the lesions, already presenting as problematic wounds and at high risk of necrotizing soft tissue infection with compartment aspects. The regimen consisted of six treatments, one daily at 2.4 atmospheres absolute at 25 minutes x3 (75 minutes) at FiO2=1, with two five-minute air breaks interposed. The therapy was well tolerated in spite of the patient's declared trait of claustrophobia. Our findings at a long-term follow up suggest that HBO2 therapy may be reasonably and effectively administered at least in the post-acute phase of such occurrences.

Preconditioning with hyperbaric oxygen in pancreaticoduodenectomy: a randomized double-blind pilot study.

UNLABELLED: In a prospective randomized double-blind study, we evaluated the post-operative biological and clinical effects of a single preoperative hyperbaric-treatment the day before surgery for pancreatic ductal adenocarcinoma. PATIENTS AND METHODS: Twenty one patients were randomized and divided into two groups: group-A (10 patients, 48%) were exposed to a HyperBaric Oxygen (HBO) session the day before intervention [Pre-Intervention Day (PID)], group-B (11 patients, 52%) breathed air for 40 min in a hyperbaric chamber pressurized to 1.15 ATA (placebo group). For all patients blood samples were obtained before HBO treatment or the placebo procedure (T0); at the end of HBO session or placebo procedure (T1); on the first post-operative day (POD)(T2) and on seventh POD(T3) day, measuring interleukin (IL)-1, IL-6, IL-8, IL-10, IL-12 and TNF-α, recording postoperative pancreatic fistula (POPF), biliary-fistula, fever, intra-abdominal abscess, bleeding, pulmonary complications, delayed gastric emptying and requirement for post-operative antibiotics. The results of the present pilot study suggest that a single preoperative hyperbaric oxygen treatment on the day before surgery may reduce the complication rate in pancreatic resection.

Oxybiotest project: microorganisms under pressure. Hyperbaric oxygen (HBO) and simple pressure interaction on selected bacteria.

BACKGROUND: HyperBaric Oxygen (HBO) therapy involves exposure to pure oxygen in a pressurized room, and it is an already well-established treatment for various conditions, including those originated by serious infections. Starting from the observation of an increased number of patients who were accessing our HBO units for diseases supported from concomitant multidrug-resistant microorganisms, as well as considering the evident clinical benefit and laboratory final outcome of those patients at the end of the treatment, aim of our study was to measure, or better define at least, if there was any interaction between a hyperbaric environment and some selected microorganisms and if those positive results were due to the increased oxygen partial pressure (pO2) value or just to the increased pressure, regardless of the fraction of inspired oxygen (FiO2) applied (21÷100%). DESIGN AND METHODS: We applied various increased pO2 values in a hyperbaric environment. Our study design was tailored in four steps to answer four specific questions, ordered in a progressive process: OxyBioTest (OBT)-1,2,3, and 4. Specifically, we chose to investigate possible changes in the Minimum Inhibitory Concentration (MIC) and in the Minimum Bactericidal Concentration (MBC) of multi-resistant microorganisms after a single session of hyperbaric therapy. RESULTS: OBT-1 and OBT-2 provide a semi-quantitative confirmation of the bacterio-cidal and cytostatic effects of HBO. HBO is cidal only if the total exposure pressure is elevated, and cidal or cytostatic effect are not always dependent on the pO2 applied.OBT-4 has shown the adjuvant effect of HBO and antimicrobial drug against some selected bacteria. DISCUSSION: We seem allowed to hypothesize that only in case of a good approach to a lesion, permitting smaller bacterial loads thanks to surgical debridement and/or eventual antibiotic therapy for example, You can observe the clear effectiveness of the HyperBaric Oxygen (HBO) exposure as a valid adjuvant therapy, even when that lesion is substained from multidrug-resistant micro-organisms. On the contrary when the bacterial load is very high we observe an unchanged situation or a just a slightly diminishing in the number of cfu/ml. CONCLUSIONS: Even if confined in this 'in vitro' environment and in a single treatment, just knowing the microorganism strain responsible of the lesion we seem allowed to both weight the possible related effectiveness using HBO Therapy (HBOT) and derive the best pO2 to treat the case. A further possible development of the study highlights a comparison between Acinetobacter baumannii (ACBA) and Pseudomonas aeruginosa (PSAE), and Escherichia coli (ESCO) and Klebsiella pneumoniae (KLPN).