Pneumothorax during manned chamber operations: A summary of reported cases.

In-chamber pneumothorax has complicated medically remote professional diving operations, submarine escape training, management of decompression illness, and hospital-based provision of hyperbaric oxygen therapy. Attempts to avoid thoracotomy by combination of high oxygen partial pressure breathing (the concept of inherent unsaturation) and greatly slowed rates of chamber decompression proved successful on several occasions. When this delicate balance designed to prevent the intrapleural gas volume from expanding faster than it contracts proved futile, chest drains were inserted. The presence of pneumothorax was misdiagnosed or missed altogether with disturbing frequency, resulting in wide-ranging clinical consequences. One patient succumbed before the chamber had been fully decompressed. Another was able to ambulate unaided from the chamber before being diagnosed and managed conventionally. In between these two extremes, patients experienced varying degrees of clinical compromise, from respiratory distress to cardiopulmonary arrest, with successful resuscitation. Pneumothorax associated with manned chamber operations is commonly considered to develop while the patient is under pressure and manifests during ascent. However, published reports suggest that many were pre-existing prior to chamber entry. Risk factors included pulmonary barotrauma-induced cerebral arterial gas embolism, cardiopulmonary resuscitation, and medical or surgical procedures usually involving the lung. This latter category is of heightened importance to hyperbaric operations as an iatrogenically induced pneumothorax may take as long as 24 hours to be detected, perhaps long after a patient has been cleared for chamber exposure.

Pulmonary barotrauma as a complication of mechanical ventilation for management of COVID-19 associated acute respiratory distress syndrome (CARDS).

Objectives: To identify that incidence of pulmonary barotrauma secondary to mechanical ventilation for the management of acute respiratory distress syndrome associated with coronavirus-disease-2019, and to compare it with the incidence of pulmonary barotrauma trauma secondary to mechanical ventilation associated with all the other causes. METHODS: The retrospective case-control study was conducted at the Aga Khan University Hospital, Karachi, and comprised data from October 2020 to March 2021 of patients who underwent mechanical ventilation. The data was divided into two groups. Data of acute respiratory distress syndrome associated with coronavirus-disease-2019 was in group 1, and that of acute respiratory distress syndrome associated with any other cause in control group 2. Medical records were reviewed to obtain demographic and clinical data, while the institutional picture archiving and communication system was used to review radiological images. Data was analysed using SPSS 24. RESULTS: Of the 261 cases, 115(44%) were in group 1; 87(75.6%) males and 28(24.3%) females. There were 146(56%) controls in group 2; 96(65.7%) males and 50(34.2%) females. There were 142(54.4%) subjects aged >60 years; 61(43%) in group 1 and 81(57%) in group 2. The incidence of pulmonary barotrauma in group 1 was 39(34%) and 8(5.5%) in group 2 (p<0.0001). CONCLUSIONS: Mechanical ventilation in the management of acute respiratory distress syndrome associated with coronavirusdisease- 2019 was found to be associated with a significantly higher incidence of pulmonary barotrauma than acute respiratory distress syndrome associated with any other cause.

Incidence of dental barotrauma and temporomandibular joint problems of divers in Turkey.

Introduction: In this study, we aimed to examine dental barotrauma and temporomandibular joint (TMJ) complaints in a large group of divers. Methods: This survey study included scuba divers older than 18. The questionnaire contained 25 questions about the demographic characteristics of divers, dental health behaviors, and diving-related dental, sinus and/or temporomandibular joint pain. Results: The study group consisted of 287 instructors, recreational and commercial divers (mean age 38.96 years) (79.1% males). A total of 46% of divers reported a frequency of tooth brushing less than twice a day; 28% never receive a routine dental examination; 22.6% experienced dental pain after and/or during diving, mostly in the upper posterior teeth (40%); 17% required dental treatment; 77% of these cases are restoration fracture. TMJ symptoms after diving were statistically significantly higher in women (p=0.04). Jaw and masticatory muscle pain in the morning (p≺0.001) limitation of mouth opening (p=0.04) and joint sounds in daily life (p≺0.001) were recorded as exacerbated after diving; the results were found to be statistically significant. Conclusion: In our study, the localization of barodontalgia was consistent with the distribution of caries and restored tooth areas in the literature. Dive-related TMJ pain was also more common in those with pre-dive problems such as bruxism and joint noise. Our results are important to remind us of the necessity of preventive dentistry practices and early diagnosis of problems in divers. Divers should take personal precautions, such as brushing their teeth twice a day and avoiding the need for urgent treatment. The use of a personalized mouthpiece is also recommended for divers to prevent dive-related temporomandibular joint diseases.

HYPERACTIVE BLADDER SYNDROME SECONDARY TO BAROTRAUMA AND CHRONIC STRESS.

OBJECTIVE: The aim: To improve the results of treatment of hyperactive bladder syndrome in men of working age on the background of barotrauma and stress, as a consequence of combat trauma. PATIENTS AND METHODS: Materials and methods: An analysis of the questionnaire and the results of the clinical examination of 32 patients, injured servicemen and people who were injured in combat zones was carried out. The drug solifenacin succinate was used in the treatment complex, which is a specific antagonist of M3 subtype cholinergic receptors. Its influence allows you to achieve relaxation of the bladder detrusor and reduce the contractility of hyperactive bladder. RESULTS: Results: The main criterion for the effectiveness of the treatment was a decrease in the number of urgent cases, the frequency of urination and manifestations of nocturia by 50% or more, which was considered a positive effect. At the same time, the positive effect was differentiated as follows : an improvement of these parameters by 75% or more from the initial value which is a good result; reduction of symptoms in the range of 50-75% is satisfactory; less than 50% is an unsatisfactory result. A positive effect from the treatment after 8 weeks was observed in 88% of patients, of which 52% had a good result and 36% had a satisfactory result. CONCLUSION: Conclusions: The proposed complex of treatment of hyperactive bladder syndrome as a result of combat trauma against the background of barotrauma with neurological consequences and chronic stress allows to achieve a pronounced clinical effect in the vast majority of male patients of working age. And the diagnostic complex allows you to emphasize aspects of clinical vigilance, both for doctors of a specialized branch and of doctors of a general direction.

Effect of sigh in lateral position on postoperative atelectasis in adults assessed by lung ultrasound: a randomized, controlled trial.

BACKGROUND: Postoperative atelectasis occurs in 90% of patients receiving general anesthesia. Recruitment maneuvers (RMs) are not always effective and frequently associated with barotrauma and hemodynamic instability. It is reported that many natural physiological behaviors interrupted under general anesthesia could prevent atelectasis and restore lung aeration. This study aimed to find out whether a combined physiological recruitment maneuver (CPRM), sigh in lateral position, could reduce postoperative atelectasis using lung ultrasound (LUS). METHODS: We conducted a prospective, randomized, controlled trial in adults with open abdominal surgery under general anesthesia lasting for 2 h or longer. Subjects were randomly allocated to either control group (C-group) or CPRM-group and received volume-controlled ventilation with the same ventilator settings. Patients in CPRM group was ventilated in sequential lateral position, with the addition of periodic sighs to recruit the lung. LUS scores, dynamic compliance (Cdyn), the partial pressure of arterial oxygen (PaO2) and fraction of inspired oxygen (FiO2) ratio (PaO2/FiO2), and other explanatory variables were acquired from each patient before and after recruitment. RESULTS: Seventy patients were included in the analysis. Before recruitment, there was no significant difference in LUS scores, Cdyn and PaO2/FiO2 between CPRM-group and C-group. After recruitment, LUS scores in CPRM-group decreased significantly compared with C-group (6.00 [5.00, 7.00] vs. 8.00 [7.00, 9.00], p = 4.463e-11 < 0.05), while PaO2/FiO2 and Cdyn in CPRM-group increased significantly compared with C-group respectively (377.92 (93.73) vs. 309.19 (92.98), p = 0.008 < 0.05, and 52.00 [47.00, 60.00] vs. 47.70 [41.00, 59.50], p = 6.325e-07 < 0.05). No hemodynamic instability, detectable barotrauma or position-related complications were encountered. CONCLUSIONS: Sigh in lateral position can effectively reduce postoperative atelectasis even without causing severe side effects. Further large-scale studies are necessary to evaluate it's long-term effects on pulmonary complications and hospital length of stay. TRIAL REGISTRATION: ChiCTR1900024379 . Registered 8 July 2019,.

Dysbarism: An Overview of an Unusual Medical Emergency.

Dysbarism is a general term which includes the signs and symptoms that can manifest when the body is subject to an increase or a decrease in the atmospheric pressure which occurs either at a rate or duration exceeding the capacity of the body to adapt safely. In the following review, we take dysbarisms into account for our analysis. Starting from the underlying physical laws, we will deal with the pathologies that can develop in the most frequently affected areas of the body, as the atmospheric pressure varies when acclimatization fails. Manifestations of dysbarism range from itching and minor pain to neurological symptoms, cardiac collapse, and death. Overall, four clinical pictures can occur: decompression illness, barotrauma, inert gas narcosis, and oxygen toxicity. We will then review the clinical manifestations and illustrate some hints of therapy. We will first introduce the two forms of decompression sickness. In the next part, we will review the barotrauma, compression, and decompression. The last three parts will be dedicated to gas embolism, inert gas narcosis, and oxygen toxicity. Such an approach is critical for the effective treatment of patients in a hostile environment, or treatment in the emergency room after exposure to extreme physical or environmental factors.

Outcomes of Barotrauma in Critically Ill COVID-19 Patients With Severe Pneumonia.

BACKGROUND: Pneumomediastinum and pneumothorax are complications which may be associated with barotrauma in mechanically ventilated patients. The current literature demonstrates unclear outcomes regarding barotrauma in critically ill patients with severe COVID-19. The purpose of this study was to examine the incidence of barotrauma in patients with severe COVID-19 pneumonia and its influence on survival. STUDY DESIGN AND METHODS: A retrospective cohort study was performed from March 18, 2020 to May 5, 2020, with follow-up through June 18, 2020, encompassing critically ill intubated patients admitted for COVID-19 pneumonia at an academic tertiary care hospital in Brooklyn, New York. Critically ill patients with pneumomediastinum, pneumothorax, or both (n = 75) were compared to those without evidence of barotrauma (n = 206). Clinical characteristics and short-term patient outcomes were analyzed. RESULTS: Barotrauma occurred in 75/281 (26.7%) of included patients. On multivariable analysis, factors associated with increased 30-day mortality were elevated age (HR 1.015 [95% CI 1.004-1.027], P = 0.006), barotrauma (1.417 [1.040-1.931], P = 0.027), and renal dysfunction (1.602 [1.055-2.432], P = 0.027). Protective factors were administration of remdesivir (0.479 [0.321-0.714], P < 0.001) and receipt of steroids (0.488 [0.370-0.643], P < 0.001). CONCLUSION: Barotrauma occurred at high rates in intubated critically ill patients with COVID-19 pneumonia and was found to be an independent risk factor for 30-day mortality.

[A case of pulmonary barotrauma complicated with cerebral arterial air embolism in a diver].

Pulmonary barotrauma is a kind of disease caused by the injury of lung tissue or blood vessel when the gas pressure of lung is too high or too lower than the external pressure of the body, which causes the air to enter the blood vessel and adjacent tissue. It could be happened in the escape of the divers with the light diving equipment or the sailors from submarine. Generally, the decompression chamber was used to treating the disease, and the minimum air pressure of 0.5 MPa recompression therapeutic schedule was used to selecting. In November 2019, a patient with pulmonary barotrauma combined with cerebral arterial gas embolism caused by improper underwater escape with light diving equipment was admitted to the General Hospital of Eastern War Zone. He was treated with 0.12 MPa oxygen inhalation recompression scheme in the oxygen chamber pressurized with air. 7 days later, the patient recovered and discharged.

CT and MRI for the diagnosis of perilymphatic fistula: a study of 17 surgically confirmed patients.

BACKGROUND: We evaluated the usefulness of CT and MRI for the diagnosis of perilymphatic fistula (PLF) of the round (RW) and/or oval (OW) windows, with surgery as gold standard. METHODS: We retrospectively enrolled 17 patients who presented a surgically confirmed PLF of the round (RW) or oval (OW) windows. All patients were imaged by CT + MRI (T2W SSFP without contrast) prior to surgery (= gold standard). Two radiologists, analyzed the RW and OW on the side of the clinical symptoms and sensitivity (Se) + Specificity (Sp) were calculated. RESULTS: Round window fistula was the most frequent (71%). The best sign of PLF on imaging was a fluid filling of the window niches, which had good Se (83-100% for RW, 66-83% for OW) and Sp (60% for RW, 91-100% for OW). Disorientation of the footplate and pneumolabyrinth were also only observed in 50% of OW PLF. CONCLUSION: The combination of CT and MRI is a reliable tool for a fast and accurate diagnosis of round and oval window perilymphatic fistula, with good sensitivity (> 80%). The most common sign of PLF on imaging is the presence of a fluid-filling in the RW (especially if > 2/3 of the RW niche) or in the OW niches on both CT and MRI. A disorientation of the footplate or the presence of a pneumolabyrinth are clearly in favor of an oval window perilymphatic fistula.

Recurrent facial nerve baroparesis in a military diver: a case report.

Middle ear barotrauma is common in diving. However, facial nerve baroparesis is a relatively rare complication. A dehiscent facial nerve canal may be a predisposing factor to developing this complication. Although there is an increasing number of facial baroparesis cases in the literature, they are likely still under-reported. In order to avoid unnecessary recompression treatments or detrimental effects to a professional diver's career, it is important to consider this in the differential diagnosis while evaluating dive injuries. This case report describes recurrent facial baroparesis in a military diver, which manifested on contralateral sides of his face. His initial presentation was misdiagnosed as an arterial gas embolism, which led to recompression treatment and a cardiac procedure. Upon recurrence about one year later, a complete work-up was done, which included an ENT evaluation and a CT scan. Imaging demonstrated a predisposing anatomic variant bilaterally. His symptoms resolved quickly and spontaneously both times, and he has been able to return to diving.

Rescue of a submerged convulsing diver.

In 2018, the Medical Panel of the NATO Underwater Diving Working Group (UDWG) discussed the question of the rescue and management of a submerged unresponsive compressed-gas diver. The Panel reviewed the 2012 recommendation by the UHMS Diving Committee with respect to the specific recommendation in a convulsing diver using a half-face mask and separate mouthpiece, to delay surfacing until the clonic phase had subsided if the mouthpiece was in place. There is a paucity of scientific, epidemiological, experimental and observational human studies to substantiate this guidance. Experimental animal studies suggest that the likelihood of a complete airway obstruction during an ongoing seizure is low and that there is a high likelihood of surviving pulmonary barotrauma caused by complete airway closure. Airway management and control is an essential step in the management of the unresponsive diver and would be challenging to achieve in the underwater environment. Even in the military setting, it will be difficult to provide sufficient training to enable divers to handle such a situation. In this very rare scenario it is considered that emergency guidelines should be clear, concise and easy to follow. The UDWG therefore recommends that all unconscious military divers in this situation should be rescued to surface without waiting for clonic seizures to subside. Training organizations for recreational and occupational divers should consider whether this guidance should be applied for civilian divers as well.

Pulmonary barotrauma: assessment and investigation in divers.

Decompression illness (DCI) is an uncommon problem but can be significant in terms of morbidity and, very rarely, mortality. The mechanisms of DCI are pulmonary barotrauma and decompression sickness due to inert gas supersaturation. After the initial management phase, identification of predisposing factors is important to help advise divers regarding future risk and avoidance. Here we present four cases of DCI where pulmonary barotrauma was the likely causative mechanism. We highlight the important features in assessment for pulmonary barotrauma and advising divers on the risk of a recurrence.

Headache Attributed to Airplane Travel: A Review of Literature.

PURPOSE OF REVIEW: Headaches due to airplane travel are rare but documented in the literature. We aim to provide a review of diagnostic criteria and treatment for this condition. RECENT FINDINGS: Several cases of this syndrome have been reported since it was first described in 2004. Airplane headache is classified as unilateral, stabbing, orbito-frontal pain, lasting under 30 min, and occurs during ascent or descent of a plane. Patients with this condition can develop anxiety and fear of flying given the intensity and severity of the pain. The pathophysiology of this syndrome is unknown, but theories include suspected barotrauma given changes in barometric pressure during ascent and descent. There are no randomized controlled trials regarding treatment, but case reports suggest headache prevention with pre-treatment with naproxen, decongestants, and triptans prior to air travel. Some non-pharmacological therapies reported include Valsalva maneuvers, chewing, relaxation techniques, and pressure at the pain area. As more cases of headache attributed to airplane travel are reported, epidemiological data can be obtained to further understand the incidence and prevalence of this condition, which can lead to improved treatment options for patients.

Diagnosis of arterial gas embolism in SCUBA diving: modification suggestion of autopsy techniques and experience in eight cases.

The purpose of this study was to suggest modifications of autopsy techniques in order to improve post-mortem diagnosis of arterial gas embolism (AGE) based on multidisciplinary investigation of SCUBA diving fatalities. Five adult human cadavers from the voluntary donation program of the Human Anatomy Laboratory, and eight judicial autopsied bodies of SCUBA divers from the Forensic Pathology Service were assessed. Before performing any autopsies, we accessed the diving plan and the divers' profiles for each case. We then introduced a new dissection procedure that included identification, isolation, and manipulation of carotid, vertebral and thoracic arterial systems. The dissected vascular structures that allowed optimall isolation of the systemic arterial circulation were identified and ligated. In three of the eight judicial cases, we had a strongly suggestive history of arterial gas embolism following pulmonary barotrauma (PBt/AGE). In these cases, the additional arterial dissection allowed us to clearly diagnose AGE in one of them. The autopsy of the rest of the cases showed other causes of death such as asphyxia by drowning and heart attack. In all cases we were able to reject decompression sickness, and in some of them we showed the presence of artefacts secondary to decomposition and resuscitation maneuvers. These results allow us to suggest a specific autopsy technique divided into four steps, aimed at confirming or excluding some evidence of dysbaric disorders according to a re-enactment of the incident. We have demonstrated the presence of large volumes of intravascular air, which is typical of PBt/AGE.

Exophthalmia in wild-caught cod (Gadus morhua L.): development of a secondary barotrauma effect in captivity.

Capture-based aquaculture (CBA) of Atlantic cod (Gadus morhua) has become increasingly important in recent years, and increased attention is being paid to animal welfare issues linked to these activities. Earlier studies showed that some cod develop secondary exophthalmia in captivity. This study investigated the development of secondary exophthalmia in two groups of wild-caught cod, one of which was exposed to rapid decompression causing acute barotrauma (treatment group) while the other was not (control group). Photographs and radiographs before and up to 33 days after barotrauma revealed a significant increase in overall eye protrusion caused by an accumulation of gas in the orbita in the treatment group, first observed on day 9 after decompression, while no protrusions were observed in the control group. Barotrauma was thus identified as an important trigger for the development of secondary uni- or bilateral exophthalmia of wild-caught cod. Two underlying mechanisms are suggested, where the more likely is residual swim bladder gas taking the route of least resistance, while the less likely is the exsolution of gas from the blood. Our results have implications for a wide range of contexts in which cod are rapidly brought to the surface from great depth.

Is decompression illness possible during hyperbaric therapy? a case report.

A 57-year-old woman was admitted to the intensive care unit in a state of severe hypotensive shock following a session of hyperbaric oxygen (HBO2) therapy. Shock was attributed to gastric barotrauma, which resulted in a massive venous gas embolism. Gastric barotrauma was attributed to the presence of a filled gastric band/cuff during the HBO2 therapy that prevented expanding gas from escaping on decompression. After deflation of the gastric band, two additional HBO2 sessions were performed and resulted in complete symptom resolution. Vasoactive drugs could be weaned, and the patient was discharged from hospital on Day Three with complete symptom resolution. Given the risk of gastric barotrauma and venous gas embolism, physicians should be aware of gastric band history before HBO2 therapy.

Headache attributed to airplane travel: diagnosis, pathophysiology, and treatment - a systematic review.

BACKGROUND: Headache attributed to airplane travel, also named "airplane headache" (AH) is a headache that occurs during take-off and landing. Today, there are still uncertainties about the pathophysiology and treatment of AH. This systematic review was performed to facilitate identification of the existing literature on AH in order to discuss the current evidence and areas that remain to be investigated in AH. METHODS: The systematic literature search was performed in 3 relevant medical databases; PubMed, Scopus, and Embase. The search yielded 220 papers and the papers were sorted based on inclusion and exclusion criteria established for this study. RESULTS: This systematic review included 39 papers. Main findings revealed that AH attacks are clinically stereotyped and appear mostly during landing phases. The headache presents as a severe painful headache that often disappears within 30 min. The pain is unilateral and localized in the fronto-orbital region. Sinus barotrauma has been considered as the main cause of AH. Nonsteroidal anti-inflammatory drugs and triptans have been taken by passengers with AH, to relieve the headache. CONCLUSIONS: Based on this systematic review, further studies seem required to investigate underlying mechanisms in AH and also to investigate the biological effects of nonsteroidal anti-inflammatory drugs and triptans for alleviating of AH. These studies would advance our understanding of AH pathogenesis and potential use of treatments that are not yet established.