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INTRODUCTION: Limited evidence suggests that shorter recompression schedules may be as efficacious as the US Navy Treatment Table 6 (USN TT6) for treatment of milder presentations of decompression sickness (DCS). This study aimed to determine if divers with mild DCS could be effectively treated with a shorter chamber treatment table. METHODS: All patients presenting to the Fremantle Hospital Hyperbaric Medicine Unit with suspected DCS were assessed for inclusion. Participants with mild DCS were randomly allocated to receive recompression in a monoplace chamber via either a modified USN TT6 (TT6m) or a shorter, custom treatment table (FH01). The primary outcome was the number of treatments required until resolution or no further improvement (plateau). RESULTS: Forty-one DCS cases were included, 21 TT6m and 20 FH01. Two patients allocated to FH01 were moved to TT6m mid-treatment due to failure to significantly improve (as per protocol), and two TT6m required extensions. The median total number of treatments till symptom resolution was 1 (IQR 1-1) for FH01 and 2 (IQR 1-2) for TT6m (P = 0.01). More patients in the FH01 arm (17/20, 85%) showed complete symptom resolution after the initial treatment, versus 8/21 (38%) for TT6m (P = 0.003). Both FH01 and TT6m had similar overall outcomes, with 19/20 and 20/21 respectively asymptomatic at the completion of their final treatment (P = 0.97). In all cases where two-week follow-up contact was made, (n = 14 FH01 and n = 12 TT6m), patients reported maintaining full symptom resolution. CONCLUSIONS: The median total number of treatments till symptom resolution was meaningfully fewer with FH01 and the shorter treatment more frequently resulted in complete symptom resolution after the initial treatment. There were similar patient outcomes at treatment completion, and at follow-up. We conclude that FH01 appears superior to TT6m for the treatment of mild decompression sickness.
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Enfermedad de Descompresión , Buceo , Oxigenoterapia Hiperbárica , Descompresión/métodos , Enfermedad de Descompresión/diagnóstico , Buceo/efectos adversos , Humanos , Oxigenoterapia Hiperbárica/efectos adversos , Estudios Prospectivos , Método Simple CiegoRESUMEN
BACKGROUND Hyperbaric oxygen (HBO2) therapy in a multiplace chamber is the standard treatment for severe altitude decompression illness (DCI). However, some hospitals may only have a monoplace chamber. Herein, we present the case of a patient with severe altitude DCI caused by rapid decompression during an actual flight operation that was successfully treated through emergency HBO2 therapy with the Hart-Kindwall protocol, a no-air-break tables with the minimal-pressure oxygen approach in a monoplace chamber due to unavailability of rapid access to a multiplace chamber. CASE REPORT A 34-year-old male aviator presented with chest pain, paresthesia, and mild cognitive impairment following rapid decompression 20 minutes after take-off, which comprised 10 minutes of reaching a height of 10 058 m (33 000 feet) and 10 minutes of cruising at that altitude. He then initiated flight descent and landing. He visited a primary clinic, and severe DCI was suggested clinically. However, since the closest hospital with a multiplace chamber was a 3-hour drive away, we provided emergency HBO2 therapy with the Hart-Kindwall protocol in a monoplace chamber at a nearby hospital 4 hours after the initial decompression. He recovered fully and returned to flight duty 2 weeks later. CONCLUSIONS Emergency HBO2 therapy with the Hart-Kindwall protocol in a monoplace chamber may be a suitable option for severe DCI, especially in remote locations with no access to facilities with a multiplace chamber. However, prior logistical coordination must be established to transfer patients to hospitals with multiplace chambers if their symptoms do not resolve.
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Enfermedad de Descompresión , Oxigenoterapia Hiperbárica , Adulto , Dolor en el Pecho , Descompresión/métodos , Enfermedad de Descompresión/diagnóstico , Enfermedad de Descompresión/terapia , Humanos , Oxigenoterapia Hiperbárica/métodos , MasculinoRESUMEN
RATIONALE: With the spread of computers and mobile phones, cervical spondylosis has become a common occupational disease in clinics, which seriously affects the quality of life of patients. We used a nonsurgical spinal decompression system (SDS) combined with physical therapy electroacupuncture (EA) to treat a case of mixed cervical spondylosis caused by multi-level cervical disc herniation, and we achieved satisfactory results. PATIENT CONCERNS: A 44-year-old Caucasian Asian woman presented with neck pain and numbness on the left side of the limb. MRI showed the patient's C3-C7 segment cervical disc herniation, and the flexion arch of the cervical spine was reversed. DIAGNOSIS: The patient was diagnosed with a mixed cervical spondylosis. INTERVENTIONS: The patient received a month of physical therapy (SDS traction combined with EA). OUTCOMES: Before and after treatment: VAS score of neck pain decreased from 8 to 0; Cervical spine mobility returned to normal; The grip strength of left hand increased from 7.5âkg to 19.2âkg; Cervical curvature index changed from -16.04% to -3.50%; the physiological curvature of the cervical spine was significantly restored. There was no dizziness or neck discomfort at 6âmonth and 1âyear follow-up. LESSONS SUBSETIONS: SDS traction combined with EA is effective for the treatment of cervical disc herniation and can help restore and rebuild the biomechanical balance of the cervical spine.
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Vértebras Cervicales/diagnóstico por imagen , Descompresión/métodos , Electroacupuntura/métodos , Desplazamiento del Disco Intervertebral/terapia , Dolor de Cuello/etiología , Tracción , Adulto , Femenino , Humanos , Desplazamiento del Disco Intervertebral/psicología , Imagen por Resonancia Magnética , Dolor de Cuello/terapia , Calidad de Vida , Espondilosis/terapia , Resultado del TratamientoRESUMEN
Exposure to a reduction in ambient pressure such as in high-altitude climbing, flying in aircrafts, and decompression from underwater diving results in circulating vascular gas bubbles (i.e., venous gas emboli [VGE]). Incidence and severity of VGE, in part, can objectively quantify decompression stress and risk of decompression sickness (DCS) which is typically mitigated by adherence to decompression schedules. However, dives conducted at altitude challenge recommendations for decompression schedules which are limited to exposures of 10,000 feet in the U.S. Navy Diving Manual (Rev. 7). Therefore, in an ancillary analysis within a larger study, we assessed the evolution of VGE for two hours post-dive using echocardiography following simulated altitude dives at 12,000 feet. Ten divers completed two dives to 66 fsw (equivalent to 110 fsw at sea level by the Cross correction method) for 30 minutes in a hyperbaric chamber. All dives were completed following a 60-minute exposure at 12,000 feet. Following the dive, the chamber was decompressed back to altitude for two hours. Echocardiograph measurements were performed every 20 minutes post-dive. Bubbles were counted and graded using the Germonpré and Eftedal and Brubakk method, respectively. No diver presented with symptoms of DCS following the dive or two hours post-dive at altitude. Despite inter- and intra-diver variability of VGE grade following the dives, the majority (11/20 dives) presented a peak VGE Grade 0, three VGE Grade 1, one VGE Grade 2, four VGE Grade 3, and one VGE Grade 4. Using the Cross correction method for a 66-fsw dive at 12,000 feet of altitude resulted in a relatively low decompression stress and no cases of DCS.
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Altitud , Buceo/fisiología , Embolia Aérea/diagnóstico por imagen , Adulto , Presión Atmosférica , Ejercicios Respiratorios , Descompresión/métodos , Descompresión/estadística & datos numéricos , Enfermedad de Descompresión/etiología , Enfermedad de Descompresión/prevención & control , Ecocardiografía , Embolia Aérea/etiología , Humanos , Masculino , Valores de Referencia , Agua de Mar , Entrenamiento Simulado , Factores de TiempoRESUMEN
BACKGROUND: There is equivocal evidence in support of the effectiveness of each of the three co-existing approaches to conservative treatment of cervical radiculopathy (CR): biological (regenerative), mechanical (decompression) and physical (analgesic and anti-inflammatory). The aim of the study was to compare the effectiveness of the three treatment approaches in CR. MATERIAL AND METHODS: A total of 90 patients were assigned to six treatment groups. Biological treatment: 4 ultra-sound-guided periradicular injections of ACS or PRP (1 per week); Mechanical treatment: manual therapy (MT) or traction therapy (TT) - 8 ses-sions (two per week); Physical treatment: laser therapy (LT) or collagen magnetophoresis (CM) - 8 sessions (two per week). As-sessment: before therapy (W0), after completion of the treatment (W1), two months after completion (W2). Assessment tools: NRS (0-10), NDI (0-50), cross section root area in mm2 in ultrasound examination (CRA) and hand sensorimotor function test (DPT). RESULTS: The largest reduction in mean NRS, NDI and CRA values at W2 was observed with the biological treatments (NRS: ACS 71.7%, PRP 70.6%, NDI: ACS 61.5%, PRP 56.6%, CRA: ACS 23.6 %, PRP 25%). Improvement of hand sensorimotor functions was observed at both W1 and W2 only in the PRP group. The PRP group demonstrated a stronger analgesic effect than the ACS group at W1 (58.82% compared to 43.39%), but ACS therapy had the same effectiveness during the follow-up period. Other methods reduced pain and disability at W1, but further reduction of mean NRS values during the follow-up period was only evident in the CM group (32.25%), very mild in the MM (19.35%) and LT groups (18.75%), and the TT group actually demonstrated a regression (-5.58%). In 3 cases, TT exacerbated the symptoms, which resulted in termination of the therapy. CONCLUSIONS: 1. Biological treatments were more effective than mechanical and physical therapies in reducing pain, im-proving the disability index and proprioception of the hand both immediately on completion of therapy and after a follow-up period, which may suggest their regenerative properties. 2. Physical and mechanical therapies produced improvement in the above-mentioned indicators on completion of the therapy, but subsequently exerted a very slight effect during the follow-up period without evident regenerative effects; moreover, a regression of the results was actually recorded for traction therapy. 3. Caution should be paid when using traction therapy in the acute period of root oedema, due to possible signs of intolerance of the procedure and exacerbation of the discomfort.
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Analgésicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Regeneración Ósea , Vértebras Cervicales/fisiopatología , Colágeno/uso terapéutico , Tratamiento Conservador/métodos , Radiculopatía/terapia , Adulto , Anciano , Anciano de 80 o más Años , Descompresión/métodos , Femenino , Estudios de Seguimiento , Humanos , Terapia por Láser/métodos , Masculino , Persona de Mediana Edad , Manipulaciones Musculoesqueléticas/métodos , Resultado del TratamientoRESUMEN
The aim of this study is to evaluate the efficacy of intermittent pneumatic compression (IPC) as a substitute for manual lymphatic drainage (MLD) in complete decongestive therapy (CDT) for treatment of advanced stages of breast cancer-related lymphedema. In this randomized, single-blind, controlled study, 46 patients with breast cancer-related lymphedema were divided into 2 groups. Both MLD with compression bandage (CB) group (n=24) and IPC with CB group (n=22) received treatment 3 days a week for 5 weeks. Home exercise program was also given to all patients. At the end of the 5th week, patients were treated with a daily 23-hour compression garment and home exercise routines. Assessments were taken at baseline, the fifth week, and the third month. Arm circumference was measured at 5 different areas, shoulder range of motion (ROM) was evaluated with a goniometer, pain, and tightness, and heaviness sensations were assessed with visual analog scale. Both groups had similar demographic and clinical characteristics (p<0.05). There were no significant differences between groups and both groups showed significant improvement (p<0.05) in the five measurement levels of the arm circumference at the fifth week and third month. Similarly, shoulder ROM, pain, tightness, and heaviness sensations improved in both groups (p<0.05). Both MLD and IPC as a component of CDT were found successful at 5 weeks and 3 months without superiority to each other.
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Linfedema del Cáncer de Mama/terapia , Aparatos de Compresión Neumática Intermitente , Modalidades de Fisioterapia , Anciano , Brazo/patología , Linfedema del Cáncer de Mama/diagnóstico , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Descompresión/métodos , Femenino , Humanos , Drenaje Linfático Manual , Persona de Mediana Edad , Tamaño de los Órganos , Calidad de Vida , Rango del Movimiento Articular , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del TratamientoRESUMEN
Objective: An analysis of factors that may indicate both the type and degree of dehydration of a diver's body following a dry chamber hyperbaric exposure. Methods: The study was participated by 63 men - professional divers, with extensive diving experience, aged 24-51 years (average age 32.6). The subjects underwent two hyperbaric exposures, one to a pressure of 0.3 MPa and one to a pressure of 0.6 MPa, with oxygen decompression. The exposures were carried out in a hyperbaric chamber pursuant to the decompression tables of the Polish Navy, with the observance of a 24-hour interval between exposures. Blood samples were collected from the participants in order to perform a blood morphology test. Body weight was measured with the bioelectrical impedance method using the Maltron BioScan 920 device.The results were subjected to statistical analysis. The following blood morphology parameters were analyzed: hematocrit (Ht), erythrocyte size (MCV), color index (MCHC) and body weight composition: total water (TBW), extracellular water (ECW), intracellular water (ICW). Results: The studies have shown that during a hyperbaric exposure in the chamber the diver's body becomes dehydrated, with observable loss of both intracellular water as evidenced by the reduction of hematocrit content and erythrocyte size, as well as extracellular water, with the accompanying increase in the color index. Conclusions: Hyperbaric conditions are conducive to the dehydration of the diver's body, however to a degree which does not lead to an occurrence of health hazards. Good care for one's health through proper nutrition and hydration are sufficient preventive and protective measures.
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Descompresión/efectos adversos , Deshidratación/etiología , Buceo , Oxigenoterapia Hiperbárica/efectos adversos , Oxígeno , Adulto , Composición Corporal , Agua Corporal , Peso Corporal , Descompresión/métodos , Deshidratación/sangre , Deshidratación/diagnóstico , Impedancia Eléctrica , Índices de Eritrocitos , Líquido Extracelular , Hematócrito , Humanos , Líquido Intracelular , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
BACKGROUND: Even in a landlocked country like Switzerland recreational diving is becoming more and more popular. Smaller lakes in the Alps are located at an altitude of 2500 m above sea level. The incidence of diving accidents among all helicopter emergency service missions and the consecutive medical knowledge about decompression injuries is low. Thus, a collaboration between the Swiss Air-Ambulance (Rega) and the divers alert network (DAN) was initiated to improve patient treatment and identification of decompression injury and necessity of hyperbaric oxygen therapy (HBO). METHODS: Retrospective observational study that includes all patients treated by the Rega which have been classified to have had a diving accident from 2005 to 2014. Patient and diving epidemiology was assessed and the impact of DAN collaboration on patient selection and identification of patients needing transport to HBO facilities were analysed. RESULTS: In the 10-year observational period 116 patients with diving accidents were treated by Rega. Mean patient age was 40 (SD 11) years and 95 (82%) were male. If the Rega emergency physician suspected a decompression injury (DCI), without DAN contact 27/28 (96%) of these patients were transported directly to a HBO facility, whereas with DAN contact only 53/63 (84%) needed transport to a HBO facility. DAN was involved in 66/96 (69%) of the cases with suspected DCI on scene, with a significant increase over time (p = 0.001). Mean flight time to HBO facilities was significantly longer (28.9, SD 17.7 min.), compared to non-HBO facilities (7.1, SD 3.2 min., p < 0.001). Due to specialist advice, patients may have been selected who finally did not need a transport to a HBO facility, although DCI was primarily suspected by the emergency physician on the scene. These patients experienced a significantly reduced flight time to the (non-HBO) hospital of 25.6 (SD 6.5) min. (p < 0.001). DISCUSSION: Collaboration of DAN and Rega may allow a safe patient selection and a consecutive reduction of flight time and costs. Due to international collaborations, evacuation to HBO-facilities for acute recompression therapy can be provided by HEMS within less than 30 min all over Switzerland. CONCLUSIONS: For diving accidents among HEMS missions, specialist advice by diving medicine specialists (DAN) appears mandatory to accurately identify and transport patients with decompression injury, as exposure of emergency physicians towards diving accidents and the diagnosis of DCI is low.
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Consultores , Enfermedad de Descompresión/terapia , Descompresión/métodos , Buceo/efectos adversos , Predicción , Oxigenoterapia Hiperbárica/métodos , Selección de Paciente , Accidentes , Adulto , Enfermedad de Descompresión/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Suiza/epidemiologíaRESUMEN
INTRODUCTION: Personnel rescuing survivors from a pressurized, distressed Royal Australian Navy (RAN) submarine may themselves accumulate a decompression obligation, which may exceed the bottom time limits of the Defense and Civil Institute of Environmental Medicine (DCIEM) Air and In-Water Oxygen Decompression tables (DCIEM Table 1 and 2) presently used by the RAN. This study compared DCIEM Table 2 with alternative decompression tables with longer bottom times: United States Navy XVALSS_DISSUB 7, VVAL-18M and Royal Navy 14 Modified tables. METHODS: Estimated probability of decompression sickness (PDCS), the units pulmonary oxygen toxicity dose (UPTD), the volume of oxygen required and the total decompression time were calculated for hypothetical single and repetitive exposures to 253 kPa air pressure for various bottom times and prescribed decompression schedules. RESULTS: Compared to DCIEM Table 2, XVALSS_DISSUB 7 single and repetitive schedules had lower estimated PDCS, which came at the cost of longer oxygen decompressions. For single exposures, DCIEM schedules had PDCS estimates ranging from 1.8% to 6.4% with 0 to 101 UPTD and XVALSS_DISSUB 7 schedules had PDCS of less than 3.1%, with 36 to 350 UPTD. CONCLUSIONS: The XVALSS_DISSUB 7 table was specifically designed for submarine rescue and, unlike DCIEM Table 2, has schedules for the estimated maximum required bottom times at 253 kPa. Adopting these tables may negate the requirement for saturation decompression of rescue personnel exceeding DCIEM limits.
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Enfermedad de Descompresión/terapia , Descompresión/normas , Socorristas , Enfermedades Profesionales/terapia , Trabajo de Rescate/métodos , Navíos , Medicina Submarina/métodos , Australia , Descompresión/métodos , Descompresión/estadística & datos numéricos , Buceo/fisiología , Buceo/estadística & datos numéricos , Humanos , Terapia por Inhalación de Oxígeno , Valores de Referencia , Medicina Submarina/normas , Factores de TiempoRESUMEN
INTRODUCTION: Inside chamber attendants rescuing survivors from a pressurised, distressed submarine may themselves accumulate a decompression obligation which may exceed the limits of Defense and Civil Institute of Environmental Medicine tables presently used by the Royal Australian Navy. This study assessed the probability of decompression sickness (PDCS) for medical attendants supervising survivors undergoing oxygen-accelerated saturation decompression according to the National Oceanic and Atmospheric Administration (NOAA) 17.11 table. METHODS: Estimated probability of decompression sickness (PDCS), the units pulmonary oxygen toxicity dose (UPTD) and the volume of oxygen required were calculated for attendants breathing air during the NOAA table compared with the introduction of various periods of oxygen breathing. RESULTS: The PDCS in medical attendants breathing air whilst supervising survivors receiving NOAA decompression is up to 4.5%. For the longest predicted profile (830 minutes at 253 kPa) oxygen breathing at 30, 60 and 90 minutes at 132 kPa partial pressure of oxygen reduced the air-breathing-associated PDCS to less than 3.1 %, 2.1% and 1.4% respectively. CONCLUSIONS: The probability of at least one incident of DCS among attendants, with consequent strain on resources, is high if attendants breathe air throughout their exposure. The introduction of 90 minutes of oxygen breathing greatly reduces the probability of this interruption to rescue operations.
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Enfermedad de Descompresión/terapia , Descompresión/normas , Personal de Salud , Enfermedades Profesionales/terapia , Terapia por Inhalación de Oxígeno , Trabajo de Rescate , Navíos , Medicina Submarina , Australia , Descompresión/métodos , Humanos , Consumo de Oxígeno , Terapia por Inhalación de Oxígeno/estadística & datos numéricos , Presión , Valores de Referencia , Agua de Mar , Sobrevivientes , Factores de TiempoRESUMEN
The United States Navy (USN) introduced Treatment Table 9 (USN TT9) in 1999. Its purpose is to provide a dosing protocol for cases of incomplete resolution of decompression sickness (DCS) and arterial gas embolism following initial provision of USN Treatment Table 6 (USN TT6). It also can be used for several non-diving-related acute toxicities. Prior to USN TT9, it was and remains common to use USN Treatment Table 5 (USN TT5) for 'follow-up' therapy. An exception might be cases of severe residual neurologic injury, where some prefer to repeat USN TT6. The primary role of USN TT5, however, is for treatment of 'pain only' (Type 1) DCS that has fully resolved within 10 minutes of the first oxygen breathing period at 60 feet of seawater (fsw) (284 kPa). It is thought helpful here to point out that USN TT9 offers certain safety and operational advantages over USN TT5. As USN TT9 employs a maximum pressure of 243 kPa, a marked risk reduction exists for the injured diver in terms of CNS oxygen toxicity. Seizures are reported during treatment of divers using US Navy protocols, some as early as the second and in one case during the first oxygen breathing period at 284 kPa (Mitchell SJ, personal communication, 2016). The inside attendant likewise enjoys an iatrogenic DCS risk reduction. While air breathing exposure time at 60 fsw on USN TT5 appears modest at first blush, the table can be extended at 30 fsw (203 kPa) for two additional oxygen/air cycles. Such extensions result in a not inconsiderable total exposure time of three hours. DCS risk is also increased if the treatment represents a repetitive dive for the attendant, a not uncommon event. Given the ongoing occurrence of inside attendant DCS, in some cases career ending and twice with fatal outcome, its mitigation should be aggressively pursued (author's personal files). From an operational perspective, both treatment pressure and sequencing of oxygen/air breathing cycles during delivery of USN TT9 are essentially identical to that commonly employed during multiplace chamber delivery of hyperbaric oxygen treatment. Accordingly, it is straightforward enough to incorporate follow-up decompression illness cases into daily clinical practice. Not having this dosing 'match', i.e., using USN TT5, might otherwise disrupt regularly scheduled cases. In my capacity as a medical claims adjudicator and clinical resource, I am involved, to varying degrees, in more than 300 cases of decompression illness each year. In those involving more than a single treatment, it is very much the exception, even after 17 years since its introduction, that USN TT9 is employed. The primary purpose of this correspondence, then, is to make mention of the advantages of USN TT9 and remind providers that it is indeed a standard of care in cases of incomplete relief for those who choose to base decompression injury management decisions on USN treatment procedures.
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Enfermedad de Descompresión/terapia , Descompresión/métodos , Embolia Aérea/terapia , Medicina Naval , Descompresión/normas , Humanos , Oxigenoterapia Hiperbárica , Estados UnidosRESUMEN
The objective of this study was to investigate early postoperative inflammatory small bowel obstruction (EPISBO) by applying gastrointestinal decompression to relieve abdominal distension. Thirty-six cases of patients were randomly divided into two groups: a control group (20 cases) and an observation group (16 cases). Routine continuous gastrointestinal decompression was assigned to the control group, while gastrointestinal decompression with dynamic and profound adjustment of the gastric tube and abdomen movement was assigned to the observation group, to induce abundant gastric juice and gas, and significantly relieve abdominal distension. A test was performed for each of the two groups to observe the relief time of the abdominal distension and the difference of abdominal girth of 5 cm before and after gastrointestinal decompression. Compared with the control group, the patients in the observation group with abdominal distension had earlier pain relief. More patients in the observation group had a difference of abdominal girth of 5 cm before and after gastrointestinal decompression. In gastrointestinal decompression, the method of dynamic and profound adjustment of the gastric tube and abdomen movement improve the effect of the gastrointestinal decompression, which relieves abdominal distention and promotes the postoperative recovery of organ functions.
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Descompresión/métodos , Obstrucción Intestinal/terapia , Intubación Gastrointestinal , Masaje , Complicaciones Posoperatorias/terapia , Abdomen , Antropometría , Niño , Preescolar , Procedimientos Quirúrgicos del Sistema Digestivo , Femenino , Humanos , Lactante , Masculino , Dolor Postoperatorio/etiología , Dolor Postoperatorio/terapiaRESUMEN
AIMS: The main objectives of the present study was to establish an animal model of decompression sickness (DCS) after heliox saturation diving, and to use this model to evaluate possible morphological changes in the CNS induced by DCS using structural MRI. METHODS: Two groups of rats were pressurized with heliox to 5 bar (pO2 = 50 kPa). The saturation time was three hours; decompression rate was 1 bar/10 seconds or 1 bar/20 seconds. A 7.0 Tesla small animal MRI scanner was used for detection of possible morphological changes in the brain and spinal cord, two hours and one week after the dive, compared to one week prior to the dive. RESULTS: Neurological symptoms of DCS were observed in seven out of 10 animals. MRI of the brain and spinal cord did not reveal any morphological CNS injuries. CONCLUSION: This diving procedure was successful in causing DCS in a large proportion of the animals. However, despite massive neurological signs of DCS, no visible CNS injuries were observed in the MRI scans.
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Encéfalo/patología , Enfermedad de Descompresión/patología , Modelos Animales de Enfermedad , Helio , Oxígeno , Médula Espinal/patología , Animales , Descompresión/métodos , Enfermedad de Descompresión/etiología , Enfermedad de Descompresión/terapia , Femenino , Síndrome Neurológico de Alta Presión/etiología , Oxigenoterapia Hiperbárica , Imagen por Resonancia Magnética , Presión Parcial , Ratas , Ratas WistarRESUMEN
Bubbles nucleate and develop after decompression at active spots on the luminal aspect of ovine large blood vessels. Series of bubbles were shown to detach from the active spot with a mean diameter of 0.7-1.0mm in calm conditions. The effect of mechanical disturbance (striking the bowl containing the vessel or tangential flow) was studied on ovine blood vessels stretched on microscope slides and photographed after hyperbaric exposure. Diameter on detachment after a heavy blow to the bowl was 0.87 ± 0.43 mm (mean ± SD), no different from bubbles which detached without striking the bowl (0.86 ± 0.28 mm). Bubble diameter on detachment during pulsatile tangential flow at 234 cm/min, 0.99 ± 0.36 mm, was not smaller than that seen in the same blood vessels in calm conditions (0.81 ± 0.34 mm). The active spots were stained for lipids, proving their hydrophobicity. The most abundant active spots, which produced only a few bubbles, did not stain for lipids thereafter. The possibility that phospholipids were removed along with detached bubbles may correlate with acclimation to diving. The finding of bubble production at the active spots matches observed phenomena in divers: variable sensitivity to decompression, acclimation to diving, the effect of elevated gas load on increased bubble formation, a higher bubble score in the second dive on the same day, and unexplained neurological symptoms after decompression. Large bubbles released from the arterial circulation give serious cause for concern.
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Vasos Sanguíneos/fisiología , Descompresión , Gases/sangre , Animales , Circulación Sanguínea , Descompresión/métodos , Oxigenoterapia Hiperbárica , Técnicas In Vitro , Estimulación Física/métodos , Flujo Pulsátil/fisiología , Ovinos , Estadísticas no ParamétricasRESUMEN
Decompression sickness (DCS) and central nervous system oxygen toxicity are inherent risks for "inside" attendants (IAs) of hyperbaric chambers. At the Hyperbaric Medicine Center at the University of California San Diego (UCSD), protocols have been developed for decompressing IAs. Protocol 1: For a total bottom time (TBT) of less than 80 minutes at 2.4 atmospheres absolute (atm abs) or shallower, the U.S. Navy (1955) no-decompression tables were utilized. Protocol 2: For a TBT between 80 and 119 minutes IAs breathed oxygen for 15 minutes prior to initiation of ascent. Protocol 3: For a TBT between 120-139 minutes IAs breathed oxygen for 30 minutes prior to ascent. These protocols have been utilized for approximately 28 years and have produced zero cases of DCS and central nervous system oxygen toxicity. These results, based upon more than 24,000 exposures, have an upper limit of risk of DCS and oxygen toxicity of 0.02806 (95% CI) using UCSD IA decompression Protocol 1, 0.00021 for Protocol 2, and 0.00549 for Protocol 3. We conclude that the utilization of this methodology may be useful at other sea-level multiplace chambers.
Asunto(s)
Cámaras de Exposición Atmosférica , Enfermedad de Descompresión/epidemiología , Descompresión/métodos , Enfermedades Profesionales/epidemiología , Oxígeno/envenenamiento , Convulsiones/epidemiología , Adulto , Protocolos Clínicos , Descompresión/efectos adversos , Enfermedad de Descompresión/etiología , Femenino , Humanos , Oxigenoterapia Hiperbárica/efectos adversos , Oxigenoterapia Hiperbárica/métodos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/etiología , Exposición Profesional , Oxígeno/administración & dosificación , Estudios Retrospectivos , Convulsiones/etiología , Factores de Tiempo , Adulto JovenRESUMEN
Oxygen is the most widely used therapeutic strategy to prevent and treat decompression sickness (DCS). Oxygen prebreathe (OPB) eliminated DCS in 20-kg swine after rapid decompression from saturation at 60 feet of seawater (fsw). However, hyperbaric oxygen (HBO) has risks. As oxygen partial pressure increases, so do its toxic effects. Central nervous system (CNS) oxygen toxicity is the most severe side effect, manifesting as seizure. An adjunctive therapeutic is needed to extend OPB strategies to deeper depths and prevent/delay seizure onset. The Food and Drug Administration-approved anti-epileptic vigabatrin has prevented HBO-induced seizures in rats up to 132 fsw. This study aimed to confirm the rat findings in a higher animal model and determine whether acute high-dose vigabatrin evokes retinotoxicity symptoms seen with chronic use clinically in humans. Vigabatrin dose escalation studies were conducted 20-kg swine exposed to HBO at 132 or 165 fsw. The saline group had seizure latencies of 7 and 11 min at 165 and 132 fsw, respectively. Vigabatrin at 180 mg/kg significantly increased latency (13 and 27 min at 165 and 132 fsw, respectively); 250 mg/kg abolished seizure activity at all depths. Functional electroretinogram and histology of the retinas showed no signs of retinal toxicity in any of the vigabatrin=treated animals. In the 250 mg/kg group there was no evidence of CNS oxygen toxicity; however, pulmonary oxygen toxicity limited HBO exposure. Together, the findings from this study show that vigabatrin therapy is efficacious at preventing CNS oxygen toxicity in swine, and a single dose is not acutely associated with retinotoxicity.
Asunto(s)
Anticonvulsivantes/farmacología , Oxigenoterapia Hiperbárica/efectos adversos , Hiperoxia/tratamiento farmacológico , Convulsiones/prevención & control , Vigabatrin/farmacología , Animales , Anticonvulsivantes/efectos adversos , Descompresión/métodos , Enfermedad de Descompresión/prevención & control , Modelos Animales de Enfermedad , Buceo/efectos adversos , Frecuencia Cardíaca/efectos de los fármacos , Hiperoxia/complicaciones , Masculino , Ratas , Retina/efectos de los fármacos , Retina/fisiología , Convulsiones/etiología , Sus scrofa , Vigabatrin/efectos adversosRESUMEN
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Asunto(s)
Humanos , Síndrome de la Disfunción de Articulación Temporomandibular/terapia , Acupuntura/métodos , Descompresión/métodos , Síndromes del Dolor Miofascial/terapia , Artralgia/terapiaRESUMEN
In August 2011, a one-day workshop was convened by the South Pacific Underwater Medicine Society and the Hyperbaric Technicians and Nurses Association to examine the use of deep recompression treatment tables for the treatment of decompression illness in Australia and New Zealand. The aim of the workshop was to develop a series of consensus statements to guide practice around the region. The workshop chose to focus the discussion on the use of 405 kPa (30 msw) maximum depth tables using helium-oxygen breathing periods, and covered indications, staffing and technical requirements. This report outlines the evidence basis for these discussions and summarises the series of consensus statements generated. These statements should assist hyperbaric facilities to develop and maintain appropriate policies and procedures for the use of such tables. We anticipate this work will lead to the formulation of a standard schedule for deep recompression to be developed at a future workshop.
Asunto(s)
Enfermedad de Descompresión/terapia , Descompresión/normas , Helio/uso terapéutico , Oxigenoterapia Hiperbárica/normas , Oxígeno/uso terapéutico , Australia , Descompresión/métodos , Descompresión/enfermería , Enfermedad de Descompresión/enfermería , Helio/administración & dosificación , Humanos , Oxigenoterapia Hiperbárica/enfermería , Nueva Zelanda , Oxígeno/administración & dosificación , Estándares de Referencia , Sociedades/normas , Sociedades Médicas/normas , Sociedades de Enfermería/normasRESUMEN
OBJECTIVE: To observe the therapic effects of the recompression treatment schedule D2 (breathing 100% oxygen at 0.12 MPa gauge pressure) on the type I decompression illness (DCI) by hyperbaric chamber pressurized with air. METHODS: The recompression treatment schedule D2 was from the decompression treatment tables of
Asunto(s)
Enfermedad de Descompresión/terapia , Descompresión/métodos , Oxigenoterapia Hiperbárica , Adulto , Buceo , Humanos , Oxigenoterapia Hiperbárica/métodos , Masculino , Persona de Mediana Edad , Terapia por Inhalación de Oxígeno , Resultado del TratamientoRESUMEN
INTRODUCTION: Testing of decompression procedures has been performed both in the dry and during immersion, assuming that the results can be directly compared. To test this, the aim of the present paper was to compare the number of venous gas bubbles observed following a short, deep and a shallow, long air dive performed dry in a hyperbaric chamber and following actual dives in open water. METHODS: Fourteen experienced male divers participated in the study; seven performed dry and wet dives to 24 metres' sea water (msw) for 70 minutes; seven divers performed dry and wet dives to 54 msw for 20 minutes. Decompression followed a Bühlmann decompression procedure. Immediately following the dive, pulmonary artery bubble formation was monitored for two hours. The results were graded according to the method of Eftedal and Brubakk. RESULTS: All divers completed the dive protocol, none of them showed any signs of decompression sickness. During the observation period, following the shallow dives, the bubbles increased from 0.1 bubbles per cm ² after the dry dive to 1.4 bubbles per cm ² after the wet dive. Following the deep dives, the bubbles increased from 0.1 bubbles per cm ² in the dry dive to 2.4 bubbles per cm ² in the wet dive. Both results are highly significant (P = 0.0001 or less). CONCLUSIONS: The study has shown that diving in water produces significantly more gas bubble formation than dry diving. The number of venous gas bubbles observed after decompression in water according to a rather conservative procedure, indicates that accepted standard decompression procedures nevertheless induce considerable decompression stress. We suggest that decompression procedures should aim at keeping venous bubble formation as low as possible.