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Sports Medicine (Auckland, N.Z.) 2003Asthma has traditionally been a contraindication to recreational self-contained underwater breathing apparatus (SCUBA) diving, although large numbers of patients with... (Review)
Review
Asthma has traditionally been a contraindication to recreational self-contained underwater breathing apparatus (SCUBA) diving, although large numbers of patients with asthma partake in diving. The purpose of this paper is to review all the research relevant to the issue of the safety of asthma in divers. MEDLINE and MDConsult were searched for papers between 1980-2002. Keywords used for the search were 'asthma', 'SCUBA' and 'diving'. Additional references were reviewed from the bibliographies of received articles.A total of fifteen studies were identified as relevant to the area. These included three surveys of divers with asthma, four case series and eight mechanistic investigations of the effect of diving on pulmonary function. The survey data showed a high prevalence of asthma among recreational SCUBA divers, similar to the prevalence of asthma among the general population. There was some weak evidence for an increase in rates of decompression illness among divers with asthma. In healthy participants, wet hyperbaric chamber and open-water diving led to a decrease in forced vital capacity, forced expired volume over 1.0 second and mid-expiratory flow rates. In participants with asymptomatic respiratory atopy, diving caused a decrease in airway conductivity.There is some indication that asthmatics may be at increased risk of pulmonary barotrauma, but more research is necessary. Decisions regarding diving participation among asthmatics must be made on an individual basis involving the patient through informed, shared decision making.
Topics: Asthma; Decision Making; Diving; Forced Expiratory Volume; Humans; Peak Expiratory Flow Rate; Prevalence; Vital Capacity
PubMed: 12617690
DOI: 10.2165/00007256-200333020-00003 -
BMJ (Clinical Research Ed.) May 2010To determine clinical and physiological effects of high frequency oscillation compared with conventional ventilation in patients with acute lung injury/acute respiratory... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To determine clinical and physiological effects of high frequency oscillation compared with conventional ventilation in patients with acute lung injury/acute respiratory distress syndrome (ARDS).
DESIGN
Systematic review and meta-analysis.
DATA SOURCES
Electronic databases to March 2010, conference proceedings, bibliographies, and primary investigators.
STUDY SELECTION
Randomised controlled trials of high frequency oscillation compared with conventional ventilation in adults or children with acute lung injury/ARDS. Data selection Three authors independently extracted data on clinical, physiological, and safety outcomes according to a predefined protocol. We contacted investigators of all included studies to clarify methods and obtain additional data. Analyses used random effects models.
RESULTS
Eight randomised controlled trials (n=419 patients) were included; almost all patients had ARDS. Methodological quality was good. The ratio of partial pressure of oxygen to inspired fraction of oxygen at 24, 48, and 72 hours was 16-24% higher in patients receiving high frequency oscillation. There were no significant differences in oxygenation index because mean airway pressure rose by 22-33% in patients receiving high frequency oscillation (P=0.01). In patients randomised to high frequency oscillation, mortality was significantly reduced (risk ratio 0.77, 95% confidence interval 0.61 to 0.98, P=0.03; six trials, 365 patients, 160 deaths), and treatment failure (refractory hypoxaemia, hypercapnoea, hypotension, or barotrauma) resulting in discontinuation of assigned therapy was less likely (0.67, 0.46 to 0.99, P=0.04; five trials, 337 patients, 73 events). Other risks were similar. There was substantial heterogeneity between trials for physiological (I(2)=21-95%) but not clinical (I(2)=0%) outcomes. Pooled results were based on few events for most clinical outcomes.
CONCLUSION
High frequency oscillation might improve survival and is unlikely to cause harm. As ongoing large multicentre trials will not be completed for several years, these data help clinicians who currently use or are considering this technique for patients with ARDS.
Topics: Acute Lung Injury; High-Frequency Ventilation; Humans; Randomized Controlled Trials as Topic; Respiration, Artificial; Respiratory Distress Syndrome; Treatment Outcome
PubMed: 20483951
DOI: 10.1136/bmj.c2327 -
Intensive Care Medicine Experimental Dec 2020In patients with acute respiratory distress syndrome (ARDS), lung recruitment could be maximised with the use of recruitment manoeuvres (RM) or applying a positive... (Review)
Review
Effects of higher PEEP and recruitment manoeuvres on mortality in patients with ARDS: a systematic review, meta-analysis, meta-regression and trial sequential analysis of randomized controlled trials.
PURPOSE
In patients with acute respiratory distress syndrome (ARDS), lung recruitment could be maximised with the use of recruitment manoeuvres (RM) or applying a positive end-expiratory pressure (PEEP) higher than what is necessary to maintain minimal adequate oxygenation. We aimed to determine whether ventilation strategies using higher PEEP and/or RMs could decrease mortality in patients with ARDS.
METHODS
We searched MEDLINE, EMBASE and CENTRAL from 1996 to December 2019, included randomized controlled trials comparing ventilation with higher PEEP and/or RMs to strategies with lower PEEP and no RMs in patients with ARDS. We computed pooled estimates with a DerSimonian-Laird mixed-effects model, assessing mortality and incidence of barotrauma, population characteristics, physiologic variables and ventilator settings. We performed a trial sequential analysis (TSA) and a meta-regression.
RESULTS
Excluding two studies that used tidal volume (V) reduction as co-intervention, we included 3870 patients from 10 trials using higher PEEP alone (n = 3), combined with RMs (n = 6) or RMs alone (n = 1). We did not observe differences in mortality (relative risk, RR 0.96, 95% confidence interval, CI [0.84-1.09], p = 0.50) nor in incidence of barotrauma (RR 1.22, 95% CI [0.93-1.61], p = 0.16). In the meta-regression, the PEEP difference between intervention and control group at day 1 and the use of RMs were not associated with increased risk of barotrauma. The TSA reached the required information size for mortality (n = 2928), and the z-line surpassed the futility boundary.
CONCLUSIONS
At low V, the routine use of higher PEEP and/or RMs did not reduce mortality in unselected patients with ARDS.
TRIAL REGISTRATION
PROSPERO CRD42017082035 .
PubMed: 33336325
DOI: 10.1186/s40635-020-00322-2 -
Minerva Anestesiologica Sep 2022Barotrauma is rare in patients with acute respiratory distress syndrome undergoing mechanical ventilation. Its incidence seems increased among critically ill COVID-19... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Barotrauma is rare in patients with acute respiratory distress syndrome undergoing mechanical ventilation. Its incidence seems increased among critically ill COVID-19 patients. We performed a systematic review and meta-analysis to investigate the incidence, risk factors and clinical outcomes of barotrauma among critically ill COVID-19 patients.
EVIDENCE ACQUISITION
PubMed was searched from March 1, 2020 to August 31, 2021; case series and retrospective cohort studies concerning barotrauma in adult critically ill COVID-19 patients, either hospitalized in the Intensive Care Unit (ICU) or invasively ventilated were included. Primary outcome was the incidence of barotrauma in COVID-19 versus non-COVID-19 patients. Secondary outcomes were clinical characteristics, ventilator parameters, mortality and length of stay between patients with and without barotrauma.
EVIDENCE SYNTHESIS
We identified 21 studies (six case series, 15 retrospective cohorts). The overall incidence of barotrauma was 11 [95% CI: 8-14]% in critically ill COVID-19 patients, vs. 2 [1-3]% in non-COVID-19, P<0.001; the incidence in mechanically ventilated patients was 14 [11-17]% vs. 4 [2-5]% non-COVID-19 patients, P<0.001. There were no differences in demographic, clinical, ventilatory parameters between patients who did and did not develop barotrauma, while, on average, protective ventilation criteria were always respected. Among COVID-19 patients, those with barotrauma had a higher mortality (60 [55-66] vs. 48 [42-54]%, P<0.001) and a longer ICU length of stay (20 [14-26] vs. 13 [10,5-16] days, P=0.03).
CONCLUSIONS
Barotrauma is a frequent complication in critically ill COVID-19 patients and is associated with a poor prognosis. Since lung protective ventilation was delivered, the ventilatory management might not be the sole factor in the development of barotrauma.
Topics: Adult; Barotrauma; COVID-19; Critical Illness; Humans; Incidence; Intensive Care Units; Respiration, Artificial; Retrospective Studies
PubMed: 35416463
DOI: 10.23736/S0375-9393.22.16258-9 -
Anesthesia and Analgesia Sep 2010Decompression illness (DCI) is caused by bubble formation in the blood or tissues after a reduction in ambient pressure. Clinically, DCI may range from a trivial illness... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Decompression illness (DCI) is caused by bubble formation in the blood or tissues after a reduction in ambient pressure. Clinically, DCI may range from a trivial illness to paralysis, loss of consciousness, cardiovascular collapse, and death. Recompression is the universally accepted standard for the treatment of DCI. When recompression is delayed, a number of strategies have been suggested to improve the outcome. We examined the effectiveness and safety of both recompression and adjunctive therapies in the treatment of DCI.
METHODS
We searched CENTRAL (Cochrane Central Register of Controlled Trials) (The Cochrane Library 2009, Issue 2); MEDLINE (Medical Literature Analysis and Retrieval System Online) (1966 to July 2009); CINAHL (Cumulative Index to Nursing and Allied Health Literature) (1982 to July 2009); EMBASE (Excerpta Medica Database) (1980 to July 2009); the Database of Randomized Controlled Trials (RCTs) in Hyperbaric Medicine (July 2009); and hand-searched journals and texts. We included RCTs that compared the effect of any recompression schedule or adjunctive therapy with a standard recompression schedule and applied no language restrictions. Three authors extracted the data independently. We assessed each trial for internal validity and resolved differences by discussion. Data were entered into RevMan 5.0 software (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2008).
RESULTS
Two RCTs satisfied the inclusion criteria. Pooling of data was not possible. In one study, there was no evidence of improved effectiveness with the addition of a nonsteroidal antiinflammatory drug to routine recompression therapy (at 6 weeks: relative risk 1.04, 95% confidence interval [CI]: 0.90-1.20, P = 0.58), but there was a reduction in the number of recompression treatments required when tenoxicam was added (P = 0.01, 95% CI: 0-1). In the other study, the odds of multiple recompressions were lower with a helium and oxygen (heliox) table compared with an oxygen treatment table (relative risk 0.56, 95% CI: 0.31-1.00, P = 0.05).
DISCUSSION
Recompression therapy is the standard for treatment of DCI, but there is no RCT evidence. The addition of a nonsteroidal antiinflammatory drug (tenoxicam) or the use of heliox may reduce the number of recompressions required, but neither improves the odds of recovery. The application of either of these strategies may be justified. The modest number of patients studied demands a cautious interpretation. Benefits may be largely economic, and an economic analysis should be undertaken. There is a case for large randomized trials of high methodological rigor to define any benefit from the use of different breathing gases and pressure profiles during recompression.
Topics: Air Pressure; Anti-Inflammatory Agents, Non-Steroidal; Decompression Sickness; Helium; Humans; Oxygen Inhalation Therapy; Piroxicam; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 20332190
DOI: 10.1213/ANE.0b013e3181cdb081 -
Military Medicine Aug 2023Operations Iraqi Freedom and Enduring Freedom saw higher rates of combat ocular trauma (COT) than any past U.S. conflict. The improvised explosive device, the signature...
INTRODUCTION
Operations Iraqi Freedom and Enduring Freedom saw higher rates of combat ocular trauma (COT) than any past U.S. conflict. The improvised explosive device, the signature weapon of the conflicts, as well as improved personal protective equipment and combat medical care all attributed to COT being the fourth most common injury sustained by wounded U.S. service members. This review describes the epidemiology, mechanisms, and treatment patterns and discusses the relationship of traumatic brain injuries (TBIs) to ocular injuries sustained by U.S. service members during the War on Terror.
MATERIALS AND METHODS
A mixed-methods review of the literature was conducted by extracting data from PubMed, Embase, and Cochrane research databases between December 15, 2020, and January 25, 2021, using the COVIDENCE review management software.
RESULTS
Of 827 articles for review, 50 were deemed relevant. Articles were separated using the Birmingham Eye Trauma Terminology into open globe, closed globe, mixed/injury management only, and TBI. Seventeen articles were found to discuss data pertaining to particular databases. Overall, six articles discussed open-globe injuries in the setting of overall COT with a reported rate of 38-64%. Three articles discussed closed-globe injuries in the context of overall COT with a rate of 39-47%. Numerous articles discussed the relationship between COT and TBI. Within the Walter Reed Ocular Trauma Database, 40% of patients with ocular trauma had concomitant TBI. Additionally, the visual sequelae of ocular trauma ranged from 9% to 50% among reporting studies. Other ocular injury patterns receiving attention include neuro-ophthalmic and oculoplastic injuries. By far the most common mechanism of COT was blast injury (64-84%), with improvised explosive devices (IEDs) accounting for 51-69% of ocular injuries. Among the large reporting databases, 41-45% of COT required surgical treatment with an overall enucleation rate of 12-17%.
CONCLUSIONS
The Global War on Terrorism saw an evolution in the types of ocular injuries sustained by U.S. service members compared to previous conflicts. The widespread use of IEDs led to injury patterns not encountered in previous conflicts. Weapons of today utilize blast and shrapnel as the mechanism for destruction. Sequelae such as TBIs and complicated head and neck trauma have pushed innovation in the field of ophthalmology. Improvements in medical technology and personal protective equipment have resulted in not only survival of previously life-threatening injuries, but also a greater chance of severe loss of vision. By analyzing ocular injury data from the trauma literature, improvements in education and training can lead to improvements in point-of-injury care and eye protection for the next generation of warfighters.
Topics: Humans; Visual Acuity; Eye Injuries; Brain Injuries, Traumatic; Iraq War, 2003-2011; Blast Injuries; Disease Progression; Retrospective Studies
PubMed: 35869887
DOI: 10.1093/milmed/usac226 -
Vibration and bubbles: a systematic review of the effects of helicopter retrieval on injured divers.Diving and Hyperbaric Medicine Dec 2018Vibration from a helicopter during aeromedical retrieval of divers may increase venous gas emboli (VGE) production, evolution or distribution, potentially worsening the...
INTRODUCTION
Vibration from a helicopter during aeromedical retrieval of divers may increase venous gas emboli (VGE) production, evolution or distribution, potentially worsening the patient's condition.
AIM
To review the literature surrounding the helicopter transport of injured divers and establish if vibration contributes to increased VGE.
METHOD
A systematic literature search of key databases was conducted to identify articles investigating vibration and bubbles during helicopter retrieval of divers. Level of evidence was graded using the Oxford Centre for Evidence-Based Medicine guidelines. A modified quality assessment tool for studies with diverse designs (QATSDD) was used to assess the overall quality of evidence.
RESULTS
Seven studies were included in the review. An in vitro research paper provided some evidence of bubble formation with gas supersaturation and vibration. Only one prospective intervention study was identified which examined the effect of vibration on VGE formation. Bubble duration was used to quantify VGE load with no difference found between the vibration and non-vibration time periods. This study was published in 1980 and technological advances since that time suggest cautious interpretation of the results. The remaining studies were retrospective chart reviews of helicopter retrieval of divers. Mode of transport, altitude exposure, oxygen and intravenous fluids use were examined.
CONCLUSION
There is some physical evidence that vibration leads to bubble formation although there is a paucity of research on the specific effects of helicopter vibration and VGE in divers. Technological advances have led to improved assessment of VGE in divers and will aid in further research.
Topics: Air Ambulances; Decompression Sickness; Diving; Embolism, Air; Humans; Prospective Studies; Retrospective Studies; Vibration
PubMed: 30517957
DOI: 10.28920/dhm48.4.241-251 -
Medicine May 2019Traumatic vascular injury is caused by explosions and projectiles (bullets and shrapnel); it may affect the arteries and veins of the limbs, and is common in wartime,...
BACKGROUND
Traumatic vascular injury is caused by explosions and projectiles (bullets and shrapnel); it may affect the arteries and veins of the limbs, and is common in wartime, triggering bleeding, and ischemia. The increasing use of high-energy weapons in modern warfare is associated with severe vascular injuries.
METHODS
To summarize the current evidence of diagnosis and treatment for traumatic vascular injury of limbs, for saving limbs and lives, and put forward some new insights, we comprehensively consulted literatures and analyzed progress in injury diagnosis and wound treatment, summarized the advanced treatments now available, especially in wartime, and explored the principal factors in play in an effort to optimize clinical outcomes.
RESULTS
Extremity vascular trauma poses several difficult dilemmas in diagnosis and treatment. The increasing use of high-energy weapons in modern warfare is associated with severe vascular injuries. Any delay in treatment may lead to loss of limbs or death. The development of diagnose and treat vascular injury of extremities are the clinical significance to the tip of military medicine, such as the use of fast, cheap, low invasive diagnostic methods, repairing severe vascular injury as soon as possible, using related technologies actively (fasciotomy, etc).
CONCLUSION
We point out the frontier of the diagnosis and treatment of traumatic vascular injury, also with a new model of wartime injury treatment in American (forward surgical teams and combat support hospitals), French military surgeons regarding management of war-related vascular wounds and Chinese military ("3 districts and 7 grades" model). Many issues remain to be resolved by further experience and investigation.
Topics: Amputation, Surgical; Ankle Brachial Index; Blast Injuries; Blood Vessel Prosthesis; Decompression, Surgical; Emergency Medicine; Extremities; Fasciotomy; Fractures, Bone; Humans; Military Medicine; Military Personnel; Retrospective Studies; Skin Transplantation; Time Factors; Trauma Severity Indices; United States; Vascular Surgical Procedures; Vascular System Injuries
PubMed: 31045795
DOI: 10.1097/MD.0000000000015406 -
Intensive Care Medicine Experimental Oct 2020Existing clinical practice guidelines support the use of neuromuscular blocking agents (NMBA) in acute respiratory distress syndrome (ARDS); however, a recent large... (Review)
Review
PURPOSE
Existing clinical practice guidelines support the use of neuromuscular blocking agents (NMBA) in acute respiratory distress syndrome (ARDS); however, a recent large randomized clinical trial (RCT) has questioned this practice. Therefore, we updated a previous systematic review to determine the efficacy and safety of NMBAs in ARDS.
METHODS
We searched MEDLINE, EMBASE (October 2012 to July 2019), the Cochrane (Central) database, and clinical trial registries ( ClinicalTrials.gov , ISRCTN Register, and WHO ICTRP) for RCTs comparing the effects of NMBA as a continuous infusion versus placebo or no NMBA infusion (but allowing intermittent NMBA boluses) on patient-important outcomes for adults with ARDS. Two independent reviewers assessed the methodologic quality of the primary studies and abstracted data.
RESULTS
Seven RCTs, including four new RCTs, met eligibility criteria for this review. These trials enrolled 1598 patients with moderate to severe ARDS at centers in the USA, France, and China. All trials assessed short-term continuous infusions of cisatracurium or vecuronium. The pooled estimate for mortality outcomes showed significant statistical heterogeneity, which was only explained by a subgroup analysis by depth of sedation in the control arm. A continuous NMBA infusion did not improve mortality when compared to a light sedation strategy with no NMBA infusion (relative risk [RR] 0.99; 95% CI 0.86-1.15; moderate certainty; P = 0.93). On the other hand, continuous NMBA infusion reduced mortality when compared to deep sedation with as needed NMBA boluses (RR 0.71; 95% CI 0.57-0.89; low certainty; P = 0.003). Continuous NMBA infusion reduced the rate of barotrauma (RR 0.55; 95% CI 0.35-0.85, moderate certainty; P = 0.008) across eligible trials, but the effect on ventilator-free days, duration of mechanical ventilation, and ICU-acquired weakness was uncertain.
CONCLUSIONS
Inconsistency in study methods and findings precluded the pooling of all trials for mortality. In a pre-planned sensitivity analysis, the impact of NMBA infusion on mortality depends on the strategy used in the control arm, showing reduced mortality when compared to deep sedation, but no effect on mortality when compared to lighter sedation. In both situations, a continuous NMBA infusion may reduce the risk of barotrauma, but the effects on other patient-important outcomes remain unclear. Future research, including an individual patient data meta-analysis, could help clarify some of the observed findings in this updated systematic review.
PubMed: 33095344
DOI: 10.1186/s40635-020-00348-6 -
Aviation, Space, and Environmental... Feb 2013Ebullism is the spontaneous evolution of liquid water in tissues to water vapor at body temperature when the ambient pressure is 47 mmHg or less. While injuries... (Review)
Review
INTRODUCTION
Ebullism is the spontaneous evolution of liquid water in tissues to water vapor at body temperature when the ambient pressure is 47 mmHg or less. While injuries secondary to ebullism are generally considered fatal, some reports have described recovery after exposure to near vacuum for several minutes. The objectives of this article are to review the current literature on ebullism and to present prevention and treatment recommendations that can be used to enhance the safety of high altitude activities and space operations.
METHODS
A systematic review was conducted on currently available information and published literature of human and animal studies involving rapid decompression to vacuum and ebullism, with subsequent development of an applicable treatment protocol.
RESULTS
Available research on ebullism in human and animal subjects is extremely limited. Literature available identified key pathophysiologic processes and mitigation strategies that were used for treatment protocol design and outlining appropriate interventions using current best medical practices and technologies.
DISCUSSION
Available literature suggests that the pathophysiology of ebullism leads to predictable and often treatable injuries, and that many exposures may be survivable. With the growing number of high altitude and space-related activities, more individuals will be at risk for ebullism. An integrated medical protocol can provide guidance for the prevention and treatment of ebullism and help to mitigate this risk in the future.
Topics: Algorithms; Altitude; Animals; Decompression Sickness; Gravity Suits; Humans; Lung; Space Flight; Steam; Vacuum; Vapor Pressure
PubMed: 23447845
DOI: 10.3357/asem.3468.2013