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At least 19 recordsLinked to original sources
PubMed2003

Decompression profile and bubble formation after dives with surface decompression: experimental support for a dual phase model of decompression.

The present study was initiated in order to determine the effect of decompression profiles on bubble formation following surface decompression using oxygen. Following an air dive to 496 kPa (130 fsw) for 90 minutes, three different profiles were tested in the pig; a USN staged decompression profile, a profile using linear continuous decompression with the same total decompression time as the USN profile (ABI) and a linear profile with half the total decompression time compared to the the first two (ABII). The subsequent surface decompression at 220 kPa lasted 68 minutes for all three schedules. The study demonstrated that, following final decompression, the two linear profiles produced the lowest amount of vascular gas, with the fastest profile producing significantly less bubbles in the Pulmonary artery than the other two. Similar results were obtained in the jugular vein. The results are in qualitative agreement with model simulation using the Reduced Gradient Bubble Model (RGBM), demonstrating that the controlling tissues are reduced from those with a half time of 40 minutes using the USN procedure to 5 minutes using the fastest linear profile.

Animals↗
PubMed2003

Neurophysiological recovery after open carpal tunnel decompression: comparison of simple decompression and decompression with epineurotomy.

Two hundred and seventy-three patients with carpal tunnel syndrome without advanced neurophysiological changes (distal motor latency below 11 ms) were randomized to treatment by open carpal tunnel release with, or without, epineurotomy. Patients were examined clinically and by nerve conduction studies preoperatively and at 3, 6 and 12 months postoperatively. We found no statistically significant difference between simple decompression and decompression combined with epineurotomy with regard to either the clinical or the neurophysiological outcome.

Carpal Tunnel Syndrome↗
PubMed2001

Active chest compression-decompression for cardiopulmonary resuscitation.

BACKGROUND: Active compression-decompression cardiopulmonary resuscitation (ACD CPR) uses a hand-held suction device, applied mid sternum, to compress the chest then actively decompress the chest after each compression. Randomised controlled trials on use of active compression decompression cardiopulmonary resuscitation have results which are discordant. OBJECTIVES: To determine clinical effects and safety of active compression-decompression cardiopulmonary resuscitation compared with standard manual cardiopulmonary resuscitation (STR). SEARCH STRATEGY: We searched the Cochrane Heart Group Specialised register (April 2001), the Cochrane library, MEDLINE and EMBASE. We checked the reference list of retrieved articles and contacted enterprises manufacturing the active decompression devices. SELECTION CRITERIA: All randomized or quasi-randomized studies comparing active compression-decompression cardiopulmonary resuscitation compared with standard manual cardiopulmonary resuscitation in adults with a cardiac arrest who received cardiopulmonary resuscitation by a trained medical or paramedical team. DATA COLLECTION AND ANALYSIS: Data were independently extracted. All data were analysed on an intention-to-treat basis. The authors of the primary studies were contacted for more information when needed. Studies were cumulated, if appropriate, and pooled relative risk (RR) estimated. Subgroup analysis according to setting (out of hospital or in hospital) and attending team composition (with physician or paramedic only) were predefined. MAIN RESULTS: Twelve trials were included: 10 were in out-of-hospital settings, one set in-hospital only and one had both in-hospital and out-of-hospital components. Allocation concealment was adequate in 4 trials. The two in-hospital studies were very different in quality (A and C) and size (773 and 53 patients). Both found no differences between ACD CPR and STR in any outcome. Trials conducted in out-of-hospital settings cumulated 4162 patients. There were no differences between ACD CPR and STR for mortality either immediately (RR 0.98 [95% CI 0.94 - 1.03]) or at hospital discharge (RR 0.99 [95% CI 0.98 - 1.01]). The pooled RR of neurological impairment, any severity, was 1.71 [95% CI 0.90 - 3.25], with a non-significant trend to more frequent severe neurological damage in survivors of ACD CPR (RR 3.11 [95% CI 0.98 - 9.83]). However, assessment of neurological outcome was limited and there were few patients with neurological damage. There was no difference between ACD CPR and STR with regard complications such as rib or sternal fractures, pneumothorax or hemothorax (RR 1.09 [95% CI 0.86 - 1.38]). Skin trauma and ecchymosis were more frequent with ACD CPR. REVIEWER'S CONCLUSIONS: Active chest compression-decompression in patients with cardiac arrest is not associated with clear benefit.

Adult↗
PubMed2006

Decompression schedule optimization with an isoprobabilistic risk of decompression sickness.

INTRODUCTION: Divers use decompression schedules to reduce the probability of occurrence of decompression sickness when returning to the surface at the end of a dive. The probability of decompression sickness resulting from these schedules varies across different dives and the models used to generate them. Usually the diver is unaware of this variance in risk. This paper describes an investigation into the feasibility of producing optimized iso-probabilistic decompression schedules that minimize the time it takes for a diver to reach the surface. METHODS: The decompression schedules were optimized using the sequential quadratic programming method (SQP), which minimizes the ascent time for a given probability of decompression sickness. The U.S. linear-exponential multi-gas model was used to calculate an estimate of the probability of decompression sickness for a given dive. In particular 1.3-bar oxygen in helium rebreather bounce dives to between 18 m and 81 m were considered and compared against the UK Navy QinetiQ 90 tables for a similar estimate of probability of decompression sickness. RESULTS: The SQP method reliably produced schedules with fast and stable convergence to an optimized solution. Comparison of the optimized decompression schedules with the QinetiQ 90 schedules showed similar stop times for shallow dives to 18 m. For dives with a maximum depth of 39 m to 81 m, optimizing the decompression resulted in savings in decompression time of up to 30 min. CONCLUSIONS: This paper has shown that it is feasible to produce optimized iso-probabilistic decompression tables given a reliable risk model for decompression sickness and appropriate dive trials.

Decompression↗
PubMed1979

Adrenal function and the incidence of bends after decompression in mice: effect of adrenalectomy, corticosteroids, decompression intensity, and time of day.

The adrenocortical endocrine subsystem has been demonstrated to enhance mammalian tolerance to harsh environmental conditions, including hypoxia and temperature extremes. In a series of factorial experiments, mice were exposed to one of three elevated hydrostatic pressures for 30 min and then decompressed (0.75 atm/s). It was demonstrated that 1) tolerance to decompression does not differ significantly (P greater than 0.3) in surgically intact, sham adrenalectomized, or in adrenalectomized animals; 2) intraperitoneal administration of pharmacologic doses (0.4, 1.0, and 2.0 mg/mouse) or corticosterone or deoxycorticosterone acetate does not significantly enhance (P greater than 0.1) survivorship when compared to vehicle-injected controls; and 3) the incidence of decompression sickness (DS) does not fluctuate with time of day (P greater than 0.4). In a fourth study, the plasma concentration of corticosterone was quantitated in 1) colony control mice, 2) mice exposed to the 1-ATA chamber environment (chamber control), or 3) mice compressed to 3, 5, 7, 9, or 11 ATA and then decompressed. In general, plasma corticosterone in symptom-free mice was elevated approximately threefold (P less than 0.05) by exposure to the 1-ATA chamber environment and by decompression from 3 to 11 ATA. At 11 ATA, plasma corticosterone levels in decompressed mice exhibiting decompression sickness symptoms were significantly elevated (P less than 0.05) compared to the levels observed in decompressed symptom-free mice. These studies indicate that adrenocortical function does not enhance tolerance to decompression in mice.

Adrenal Cortex Hormones↗
PubMed2006

Three-wall orbital decompression superiority to 2-wall orbital decompression in thyroid-associated ophthalmopathy.

PURPOSE: We evaluated the results of the 2-wall and 3-wall orbital decompression in patients with Graves' disease. PATIENTS AND METHODS: In this study, we present a consecutive series of 12 patients (18 orbits) who were submitted to orbital decompression by endoscopic transnasal medial wall combined with transantral inferior wall approach and 7 patients (8 orbits) who were submitted to orbital decompression by endoscopic transnasal medial wall, transantral inferior wall combined with transcutaneous lateral wall approach. The degree of exophthalmos was evaluated with the Hertel exophthalmometer preoperatively and postoperatively in the 24th hour, and first, third, and ninth months. RESULTS: At the end of the third month, the exophthalmos decreased by a mean of 4.38 mm (range, 3 to 7 mm) with the 2-wall decompression and 7.75 mm (range, 5 to 12 mm) with the 3-wall decompression. Visual acuity maintained or improved during the follow-up period. Ocular motility disturbance occurred in 1 patient after 2-wall decompression and in 1 patient after 3-wall orbital decompression. Postoperatively, new-onset diplopia was seen in only 1 patient after 2-wall orbital decompression. CONCLUSION: The 3-wall (endoscopic transnasal medial wall, transantral inferior wall combined with transcutaneous lateral wall) approach is as safe as the 2-wall approach. Proptosis reduction is much better with the 3-wall orbital decompression.

Adult↗
PubMed1993

[Experimental studies of the effects of enriched air nitrox dive on shortening of decompression time and reduction of risks of decompression sickness].

Enriched air nitrox diving has been conducted to shorten decompression time as well as to reduce risks of decompression sickness. Nine volunteer divers served as subjects for nitrox (-a: 60% N2 and 40% O2, and -b: 67.5% N2 and 32.5% O2) and air chamber dives of 20 m/60 min, 30 m/60 min and 40 m/60 min. Venous gas emboli (VGE) were examined after surfacing in a series of nitrox dives and of air dives to compare the risks of decompression sickness (DCS). Three divers as a group were compressed in a chamber for each dive. Decompression was carried out according to the Norwegian Navy nitrox decompression tables for the nitrox dives, and for the air dives the Japanese Ministry of Labor tables were used. Decompression time was much shorter in nitrox diving than in air dives for the same dive profiles. All of nitrox-a and air divers showed no VGE nor DCS symptoms after surfacing of 20 m dives. In case of 30 m dives, VGE appeared in one diver (33%) without DCS symptoms in nitrox-a dive but no VGE nor DCS in nitrox-b dive, whereas for the same air dives two subjects (66%) had VGE and DCS symptoms. When the depth was increased to 40 m in the nitrox dive, nitrox-b did not show both VGE and DCS, while the air dive showed one VGE and one DCS. These results suggest that the nitrox dive with suitable decompression schedule reduces the risks of DCS as well as shortening decompression obligation.

Adult↗
PubMed2000

The effect of staged decompression while breathing 100% oxygen on altitude decompression sickness.

INTRODUCTION: Space Shuttle extravehicular activity (EVA) requires decompression from sea level pressure (14.7 psia) to a 4.3 psia (30,300 ft) pressure suit. The transition currently involves altering the shuttle atmosphere to allow shirt-sleeve denitrogenation to occur during a 12 to 36-h staged decompression (SD) at 10.2 psia (9,800 ft) with an oxygen-enriched breathing gas (26.5% oxygen, 73.5% nitrogen). The denitrogenation provides protection from decompression sickness (DCS) during EVA in a 4.3 psia pressure suit. Our goal was to determine the highest altitude at which SD while breathing 100% oxygen (SD100) could provide effective protection from development of DCS symptoms after further decompression to 29,500 ft (4.5 psia). METHODS: There were 30 male subjects exposed to at least 6 of 11 conditions in random order on successive months to 29,500 ft for 4 h while performing mild exercise and being monitored for venous gas emboli (VGE) with an echo-imaging system. The subjects received 15 min of ground-level (GL) preoxygenation and an additional 60 or 120 min of SD100 at one of four altitudes between 8,000 ft (10.9 psia) and 18,000 ft (7.3 psia). Control exposures followed a 75- or 135-min ground-level preoxygenation. RESULTS: During SD100, one case of DCS occurred at 18,000 ft, but not at lower staging altitudes. Higher levels of VGE were observed during SD100 at 18,000 ft than during SD100 at any lower altitude. CONCLUSION: Staged decompression at 16,000 ft and below results in decompression risk during subsequent decompression to 29,500 ft similar to that following equivalent periods of ground-level preoxygenation.

Altitude Sickness↗
PubMed2000

Prospective study of surgical treatment of degenerative spondylolisthesis: comparison between decompression alone and decompression with graf system stabilization.

STUDY DESIGN: A prospective study of patients with degenerative spondylolisthesis who underwent decompression of the spine, with and without stabilization using the Graf system. OBJECTIVES: To assess the clinical result of decompression alone and decompression using the Graf system. SUMMARY OF BACKGROUND DATA: The clinical outcome of lumbar stabilization for degenerative spondylolisthesis remains uncertain. There is no prospective study of differences in clinical outcome between patients who undergo decompression alone and those who undergo decompression and stabilization using the Graf system. METHODS: Eighty-eight patients with degenerative spondylolisthesis were included in this study. All patients reported leg symptoms. Decompression alone (Group D) was performed in 42 patients during a 5-year period from 1988 through 1992. Decompression and stabilization with the Graf system (Group G) was performed in 46 patients during a 4-year period from 1993 through 1996. There was no statistical difference regarding sex, the age at operation, compensable cases, and preoperative duration between two groups. The two groups were evaluated at follow-up examinations 1 and 3 years after surgery. The clinical results were evaluated for all patients by means of a 4-grade scale, visual analog scale, recurrence of leg symptoms, and persistent low back pain. The radiographic and clinical findings were examined by an independent investigator. RESULTS: The results according to the 4-grade scale deteriorated with time in both groups. There was no statistical difference between the two groups in the 4-grade scale, visual analog scale, or recurrence of leg symptoms at each follow-up time. Persistent low back pain in Group G was significantly lower than that in Group D at both the 1- and 3-year follow-ups. CONCLUSIONS: Although lumbar Graf stabilization had no effect in preventing the recurrence of leg symptoms, there was a significant effect on reduction of low back pain at the 1- and 3-year follow-ups.

Adult↗
PubMed2005

Incomplete chest wall decompression: a clinical evaluation of CPR performance by EMS personnel and assessment of alternative manual chest compression-decompression techniques.

BACKGROUND: Complete chest wall recoil improves hemodynamics during cardiopulmonary resuscitation (CPR) by generating relatively negative intrathoracic pressure and thus draws venous blood back to the heart, providing cardiac preload prior to the next chest compression phase. OBJECTIVE: Phase I was an observational case series to evaluate the quality of chest wall recoil during CPR performed by emergency medical services (EMS) personnel on patients with an out-of-hospital cardiac arrest. Phase II was designed to assess the quality of CPR delivered by EMS personnel using an electronic test manikin. The goal was to determine if a change in CPR technique or hand position would improve complete chest wall recoil, while maintaining adequate duty cycle, compression depth, and correct hand position placement. Standard manual CPR and three alternative manual CPR approaches were assessed. METHODS AND RESULTS: Phase I--The clinical observational study was performed by an independent observer noting incomplete chest wall decompression and correlating that observation with electronically measured airway pressures during CPR in adult patients with out-of-hospital cardiac arrest. Rescuers were observed to maintain some residual and continuous pressure on the chest wall during the decompression phase of CPR, preventing full chest wall recoil, at some time during resuscitative efforts in 6 (46%) of 13 consecutive adults (average +/- S.D. age 63 +/-5.8 years). Airway pressures were consistently positive during the decompression phase (>0 mmHg) during those observations. Phase II: This randomized prospective trial was performed on an electronic test manikin. Thirty EMS providers (14 EMT-Basics, 5 EMT-Intermediates, and 11 EMT-Paramedics), with an average age +/- S.D. of 32 +/- 8 years and 6.5 +/- 4.2 years of EMS experience, performed 3 min of CPR on a Laerdal Skill Reporter CPR manikin using the Standard Hand Position followed by 3 min of CPR (in random order) using three alternative CPR techniques: (1) Two-Finger Fulcrum Technique--lifting the heel of the hand slightly but completely off the chest during the decompression phase of CPR using the thumb and little finger as a fulcrum; (2) Five-Finger Fulcrum Technique--lifting the heel of the hand slightly but completely off the chest during the decompression phase of CPR using all five fingers as a fulcrum; and (3) Hands-Off Technique--lifting the heel and all fingers of the hand slightly but completely off the chest during the decompression phase of CPR. These EMS personnel did not know the purpose of the studies prior to or during this investigation. Adequate compression depth was poor for all hand positions tested and ranged only from 29.9 to 48.5% of all compressions. When compared with the Standard Hand Position, the Hands-Off Technique decreased mean compression duty cycle from 46.9 +/- 6.4% to 33.3 +/- 4.6%, (P < 0.0001) but achieved the highest rate of complete chest wall recoil (95.0% versus 16.3%, P < 0.0001) and was 129 times more likely to provide complete chest wall recoil (OR: 129.0; CI: 43.4-382.0). There were no significant differences in accuracy of hand placement, depth of compression, or reported increase in fatigue or discomfort with its use compared with the Standard Hand Position. CONCLUSIONS: Incomplete chest wall decompression was observed at some time during resuscitative efforts in 6 (46%) of 13 consecutive adult out-of-hospital cardiac arrests. The Hands-Off Technique decreased compression duty cycle but was 129 times more likely to provide complete chest wall recoil (OR: 129.0; CI: 43.4-382.0) compared to the Standard Hand Position without differences in accuracy of hand placement, depth of compression, or reported increase in fatigue or discomfort with its use. All forms of manual CPR tested (including the Standard Hand Position) in professional EMS rescuers using a recording manikin produced an inadequate depth of compression more than half the time. These data support development and testing of more effective means to deliver manual as well as mechanical CPR.

Adult↗
PubMed1993

Transfrontal orbital decompression after failure of transantral decompression in optic neuropathy of Graves' disease.

Transantral and transfrontal orbital decompression procedures are effective for treating optic neuropathy of Graves' disease. We studied 10 patients with Graves' disease to clarify whether transfrontal decompression is effective after prior failure of transantral orbital decompression. All patients had persistent or recurrent optic neuropathy after transantral decompression and had failed to respond to systemic corticosteroid therapy. After transfrontal decompression, visual acuity improved in 70% of the eyes, and visual field scotomas decreased in 80%. No major intraoperative or postoperative complications occurred. We conclude that in optic neuropathy of Graves' disease, transfrontal orbital decompression after failure of transantral decompression is an acceptable and beneficial salvage procedure.

Adult↗
PubMed1999

A comparison of standard cardiopulmonary resuscitation and active compression-decompression resuscitation for out-of-hospital cardiac arrest. French Active Compression-Decompression Cardiopulmonary Resuscitation Study Group.

BACKGROUND: We previously observed that short-term survival after out-of-hospital cardiac arrest was greater with active compression-decompression cardiopulmonary resuscitation (CPR) than with standard CPR. In the current study, we assessed the effects of the active compression-decompression method on one-year survival. METHODS: Patients who had cardiac arrest in the Paris metropolitan area or in Thionville, France, more than 80 percent of whom had asystole, were assigned to receive either standard CPR (377 patients) or active compression-decompression CPR (373 patients) according to whether their arrest occurred on an even or odd day of the month, respectively. The primary end point was survival at one year. The rate of survival to hospital discharge without neurologic impairment and the neurologic outcome were secondary end points. RESULTS: Both the rate of hospital discharge without neurologic impairment (6 percent vs. 2 percent, P=0.01) and the one-year survival rate (5 percent vs. 2 percent, P=0.03) were significantly higher among patients who received active compression-decompression CPR than among those who received standard CPR. All patients who survived to one year had cardiac arrests that were witnessed. Nine of 17 one-year survivors in the active compression-decompression group and 2 of 7 in the standard group, respectively, initially had asystole or pulseless electrical activity. In 12 of the 17 survivors who had received active compression-decompression CPR, neurologic status returned to base line, as compared with 3 of 7 survivors who had received standard CPR (P=0.34). CONCLUSIONS: Active compression-decompression CPR performed during advanced life support significantly improved long-term survival rates among patients who had cardiac arrest outside the hospital.

Cardiopulmonary Resuscitation↗
PubMed1976

Intracardial bubbles during decompression to altitude in relation to decompression sickness in man.

Doppler ultrasound was used in five subjects to detect intracardial gas bubbles during decompressions to altitude. At a simulated altitude of 8,000 m, neither intracardial bubbles nor symptoms of decompression sickness occurred. At 9,000 m, bubbles were registered in two subjects, one of which had questionable bends. At 11,500 m, bubbles were registered in all but one subject and two had bends. The three subjects who had not gotten bends were exposed to an air-breathing period of 30 min or, in one case, even 45 min at 2 ATA, for extra nitrogen loading, followed by decompression to 11,500 m. These subjects had heavy showers of bubbles followed by bends. In all cases with decompression sickness during the decompressions to altitude, intracardial bubbles were registered prior to the appearance of symptoms. The technique may be used in studies of decompression sickness without provoking actual symptoms, thus making the studies safer.

Brain Diseases↗
PubMed2003

[Secondary decompression trepanation in progressive post-traumatic brain edema after primary decompressive craniotomy].

Besides evacuation of epidural or subdural hematoma, early decompressive craniectomy with duraplasty has to be performed in the neurotraumatological care of patients with moderate [Glasgow Coma Scale (GCS) score 9-12 points] or severe traumatic brain injury (TBI; GCS score </=8 points) and threatening herniation. The efficacy of secondary decompressive craniectomy and duraplasty after primary trepanation is under debate due to missing evidence of improved outcome. The objectives of this study were to register the incidence of increasing brain edema after isolated TBI and primary craniectomy, to identify possible decision criteria for secondary decompressive trepanation, and to evaluate the neurological performance 6 months after discharge with the Glasgow Outcome Score (GOS). Of 131 patients who suffered from isolated TBI and had to be primarily operated between January 1997 and December 2001, 58 (male:female = 48:10; median age of 50.9 years) were included in this analysis. In 11 patients (male:female = 9:2; median age of 40.0 years) a secondary unilateral extensive or contralateral decompressive craniectomy had to be performed in the clinical course. Four of the 11 patients (36.4%) did not survive TBI; they died at a median of 1 day after revision or 6 days after TBI, respectively. In the group of secondary decompressive craniectomy we recorded admission (80.0 min after TBI) 35 min later ( p=0.009) than in the group of primary trepanation. Prehospital otorrhagia was observed more frequently ( p=0.036). In univariate analysis, arterial hypotension ( p=0.018) and otorrhagia at admission ( p=0.035), intracranial pressure (ICP) immediately after primary operation ( p=0.024), and decrease of maximal postoperative cerebral perfusion pressure (CPP; p=0.031) below the median cutoff value of 70 mmHg correlated with the event of secondary decompression craniectomy. Multivariate analysis identified decreased maximal CPP after primary trepanation as the only independent prognostic parameter (score 10.496; df=1; p=0.043) for the necessity of secondary trepanation and unfavorable GOS 6 months after discharge. In patients with isolated moderate or severe TBI, prehospital arterial hypotension as well as otorrhagia negatively influenced the mortality and morbidity. Therefore, early adjustment of arterial hypotension and the rapid transport into a neurotraumatological center are to be required for prehospital management of TBI patients. The decrease of maximal CPP below 70 mmHg despite administration of catecholamines representing the only independent prognostic parameter during monitoring in the intensive care unit seems to indicate the necessity of an operative revision as well as an unfavorable GOS 6 months after discharge.

Adult↗
PubMed2003

Combined endoscopic medial and inferior orbital decompression with transcutaneous lateral orbital decompression in Graves' orbitopathy.

PURPOSE: To determine the clinical efficacy and morbidity of combined endoscopic transnasal medial and inferior wall orbital decompression performed in conjunction with transcutaneous lateral orbital decompression. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: Thirty-four subjects (64 orbits) underwent combined orbital decompression procedures for treatment of Graves' orbitopathy. INTERVENTION: Transnasal endoscopic medial wall and floor with simultaneous transcutaneous lateral orbital decompression. MAIN OUTCOME MEASUREMENTS: Ocular motility, visual acuity, and exophthalmometry. RESULTS: No new ocular motility disturbances occurred. There was a mean gain of 0.7 Snellen lines in acuity (range +9 to -10 lines). A mean proptosis reduction of 4.2 mm was observed (range 1-9 mm). CONCLUSIONS: Combined endoscopic transnasal medial and inferior orbital wall decompression done in conjunction with transcutaneous lateral orbital decompression carries a low risk of morbidity, including new onset motility disorders, and yields anatomic retropulsion of the globe that is comparable to other methods.

Adolescent↗
PubMed2005

Use of an inspiratory impedance threshold device on a facemask and endotracheal tube to reduce intrathoracic pressures during the decompression phase of active compression-decompression cardiopulmonary resuscitation.

INTRODUCTION: Use of an inspiratory impedance threshold device (ITD) significantly increases coronary perfusion pressures and survival in patients ventilated with an endotracheal tube (ETT) during active compression-decompression cardiopulmonary resuscitation. We tested the hypothesis that the ITD could lower intratracheal pressures when attached to either a facemask or ETT. METHODS: An active and sham ITD were randomly applied first to a facemask and then to an ETT during active compression-decompression cardiopulmonary resuscitation in 13 out-of-hospital cardiac arrest patients in a randomized, double-blinded, prospective clinical trial. The compression-to-bag-valve ventilation ratio was 15:2. Airway pressures (surrogate for intrathoracic pressure) were measured with a pressure transducer. A sham and an active ITD were used for 1 min each in a randomized order, first on a facemask and then on an ETT. Statistical analyses were made using Friedman's and Wilcoxon's rank-sum tests. RESULTS: For the primary end point, mean +/- sd maximum negative intrathoracic pressures (mm Hg) during the decompression phase of cardiopulmonary resuscitation were -1.0 +/- 0.73 mm Hg with a sham vs. -4.6 +/- 3.7 mm Hg with an active ITD on the facemask (p = .003) and -1.3 +/- 1.3 mm Hg with a sham ITD vs. -7.3 +/- 4.5 mm Hg with an active ITD on an ETT (p = .0009). Decompression phase airway pressures with the facemask and ETT were not statistically different. CONCLUSIONS: Use of an active ITD attached to a facemask or an ETT resulted in a significantly lower negative intratracheal pressure during the decompression phase of active compression-decompression cardiopulmonary resuscitation when compared with controls. Airway pressures with an ITD on either a facemask or ETT were similar. The ITD-facemask combination was practical and enables rapid deployment of this life-saving technology.

Cardiography, Impedance↗
PubMed1995

Orbital decompression for non-Graves' orbitopathy: a consideration of extended indications for decompression.

Orbital decompression is typically indicated for Graves' orbitopathy. Other causes of proptosis can also be safely and effectively addressed surgically with orbital decompression. Patients with prominent globes can have significant discomfort related to exposure keratopathy, lagophthalmos, and inefficient function of the globe-eyelid interface. We present six cases of non-Graves' proptosis that were addressed with orbital decompression. Indications for surgery included hypoplastic malar eminence with scleral show, enlarged globes, and congenital shallow orbits. Successful reduction of proptosis was achieved by orbital decompression with subsequent relief of presenting symptoms. Graded balanced orbital decompression was used to minimize shifts of the muscle cone. In some cases osteotomies and advancement of the lateral wall and malar region were also employed. Complications included transient esotropia, esotropia requiring surgery, and microplate granuloma. Orbital decompression should be considered for patients with relative proptosis and related eyelid malpositions regardless of the underlying etiology.

Adult↗