Category Archives: Pulmonary Function

Biphasic Extrathoracic Pressure CPR: Results

Biphasic Extrathoracic Pressure CPR: ResultsThe five male subjects had a mean age of 60 ± 12 years. None had a witnessed arrest, and none had bystander CPR. One patient (subject 3) had prehospital ACLS. The average prehospital time interval (the time from when emergency medical services received the emergency call to when they arrived at the hospital) was 25 ± 5 min. The average inhospital time interval prior to entry into the study was 26 ±31 min (Table 1).
The intracuirass inspirator) and expiratory pressures generated bv the Have к Oscillator were -21 ± 12 cm H,0 and 36 ± 12 cm 11,0, respectively (Table 1).
The Havek Oscillator chest cuirass increased CPP from – 1.2 ± 8.6 mm Hg to 6.2 ± 6.9 mm Hg for a mean change of 7.4 ±3.1 mm Hg (p = 0.006). The increase in CPG by 10.0 ± 21.9 mm Hg (p = 0.364) is primarily due to one patient (subject 3). Table 2 lists the aortic and right atrial pressures during compression and relaxation phases. The right atrial relaxation phase pressures decreased in three subjects and increased in two subjects Link In two cases, the aortic compression phase pressure was higher with the cuirass than with the Thumper. The direction or magnitude of the pressure changes did not seem to correlate to the baseline pressures nor to body habitus.

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Biphasic Extrathoracic Pressure CPR: Methods

An on-call research team placed an aortic arch catheter (60-cm 5.8F Bunegin-Albin, Cook Critical Care, Bloomington, Ind) via the femoral artery and a right atrial catheter (22-cm 7.5F Triple Lumen, Baxter-Edwards, Irvine, Calif) via the subclavian vein. These catheters were attached to precalibrated pressure transducers (Sorenson Transpac. Abbott Systems. Bloomington, I ml) and used for pressure monitoring ( Hewlett Packard 775S Multichannel Pen Recorder, Hewlett Packard, Sunnyvale, as well as arterial and venous blood gas analysis (Nova Biomedical, W altham, Mass). Oxygen saturations were measured bv CO-oximetrv (Instrumentation Laboratory Inc. Lexington, Mass). Baseline pressure and blood gas measurements were recorded from these two catheters while the subject was receiving standard (’PH from a pneumatic compression device (Thumper) (Michigan Instruments, (.rand Rapids. Mich). The Thumper was set at a 5cm excursion at a rate of SO compressions per minute with a 50 percent dutv cvclc. The subject was ventilated with SO percent oxvgen after cvcrv fifth compression. canadian neightbor pharmacy

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Biphasic Extrathoracic Pressure CPR: Device Description

Biphasic Extrathoracic Pressure CPR: Device DescriptionBlood flow during cardiopulmonary resuscitation (CPR) has been demonstrated to occur in part by the thoracic pressure pump mechanism. According to this mechanism, systemic blood flow is driven by an intrathoracic to extrathoracic pressure gradient generated during the compression phase of CPR (focal cardiac compression is not required). This gradient is called the compression phase gradient (CPG). Retrograde flow is prevented by functional valving at the venous thoracic inlet. Coronary blood flow is driven by an aortic to right atrium pressure gradient during the decompression (or relaxation) phase of CPR. This gradient is called the coronary perfusion pressure (CPP). Animal and human studies have shown a correlation between CPP and return of spontaneous circulation (ROSC). For this reason, increasing the CPP is a primary goal of CPR.
Since the mid-1800s, ventilatory devices (such as the iron lung and chest cuirass) that function by inducing a negative intrathoracic pressure have been in use. In the early 1900s, Eisenmenger proposed that these devices could circulate blood if they alternated negative and positive thoracic pressures. Unfortunately, outside of a few successful case reports from this time period, his idea appears to have been abandoned. canadian drug mall

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Dyspnea in a Patient Years After Severe Poliomyelitis: Conclusion

Figure 1 shows the absence of flow limitation at rest but clear expiratory limitation over 26 percent of the peak tidal volume. This may occur in fit normal subjects during heavy exercise and patients with CAO, even in those with mild disease. However, the significant rise in EELV seen in our patient is more typical of patients with CAO. The response in patients with UAO, particularly that associated with expiratory obstruction, would be expected to be similar. The fact that transpulmonary pressure during peak exercise exceeded the value associated with peak expiratory flows during resting maximal maneuvers also supports the importance of the UAO in our patient. As such, it is apparent that tracheomalacia and the new vocal cord paralysis were instrumental in the symptoms noted by our patient.

The abnormal respiratory muscles in our patient were likely further disadvantaged during maximal exercise as result of the UAO. Respiratory muscle function may be impaired during exercise in patients with airflow obstruction by muscle shortening associated with the need for greater inspiratory flow and by an increase in EELV. This was particularly so in our patient. In patients with advanced amyotrophic lateral sclerosis, Kreitzer et al showed that even small added resistance markedly decreased vital capacity and flows and resulted in an increased residual volume. As a result of the increase in EELV seen in our patient, the end-inspiratory lung volume was 95 percent of total lung capacity which is increased from what is expected in normal subjects. This has been associated with a significant increase in elastic load to the respiratory muscles and an increase in the metabolic cost of breathing. The absence of significant change in sniff Pdi following exercise suggests significant muscle fatigue did not develop in our patient, however.
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Dyspnea in a Patient Years After Severe Poliomyelitis: Discussion

Dyspnea in a Patient Years After Severe Poliomyelitis: DiscussionPulmonary function in patients years after polio has been studied by various groups. Patients complaining of dyspnea in one study had a significantly lower FEVj and FVC than those who did not. In addition, it was found that peak mouth inspiratory pressure (Pimax) was near normal while peak expiratory mouth pressure (Pemax) was reduced to approximately 40 percent of predicted regardless of symptoms, suggesting significant occult neuromuscular weakness.
Our patient showed only minimal decrements in FEVj and stable FVC over the course of 16 years. However, the marked diminution in inspiratory pressures confirmed neuromuscular disease. Some authors have emphasized the utility of the vital capacity measurement in following neuromuscular function. However, there may be marked abnormality in respiratory muscle function before a significant decrease in vital capacity is seen. This was seen in our patient who had significant inspiratory muscle weakness with little alteration in spirometry.
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Dyspnea in a Patient Years After Severe Poliomyelitis: Results

The results of CPET are shown in Table 2. Peak Vo2 was in the normal range as was anaerobic threshold (AT) and HRR. This suggests an appropriate cardiac response to exercise. Ventilatory response to exercise appeared to be mechanically limited with a maximum Ve that approached the patient’s measured MW. End-tidal 02, C02, and oxygen saturation remained in the normal range throughout exercise. Figure 1 illustrates the composite maximal, resting tidal, and peak exercise tidal flow-volume loops. It is clear that EELV during peak exercise rose significantly. Furthermore, peak expiratory flow overlapped the maximal expiratory flows at this elevated lung volume. The peak inspiratory flows approached those of the maximal efforts. Although not shown graphically, transpulmonary pressure during exercise surpassed that required to achieve maximal expiratory flows during the graded maximal vital capacity efforts.
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Dyspnea in a Patient Years After Severe Poliomyelitis: Respiratory Muscle Testing

Dyspnea in a Patient Years After Severe Poliomyelitis: Respiratory Muscle TestingThis technique has been used extensively in the quantitation of changes in end-expiratory lung volume (EELV) with exercise in patients with CAO. An adequate IC was confirmed by monitoring minimal pleural pressure (see below). The flow signal during exercise was stored on a personal computer (IBM PS/2) and integrated at a later point, allowing the construction of tidal flow-volume loops during the course of exercise. End-expiratory lung volume for correct placement of these loops was calculated from the IC maneuver. buy tavist online

Pleural (Ppl) and gastric (Pg) pressures were measured using thin-walled balloons placed transnasally in the middle third of the esophagus and the stomach, respectively. A separate transducer (Validyne Co, Northridge, Calif) measured each pressure while a third transducer measured mouth pressure.

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Dyspnea in a Patient Years After Severe Poliomyelitis: Case Report

The patient’s weight (61.8 kg) was appropriate for her height (165 cm). Physical examination revealed no wheezing, stridor, peripheral muscle weakness, or fasciculation. No evidence of abnormal musculoskeletal alignment or limb length discrepancy was noted. Tracheal tomography demonstrated no fixed stenotic lesion. Laryngoscopy revealed paralysis of the left true vocal cord that was fixed in the midline position. There was also decreased abduction of the right true vocal cord with only a 3 to 4 mm glottic chink. A plot of maximal expiratory and inspiratory flow and volume (Med Science, St. Louis, Mo), created from multiple vital capacity maneuvers performed by the patient with varying effort, demonstrated flattening of both the inspiratory and expiratory limbs supporting a fixed or both variable intrathoracic and extrathoracic upper airway obstruction (Fig 1). Spirometric parameters were expressed according to the predicteds published by Morris et al. Chest radiograph was normal. canadian health mall

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Dyspnea in a Patient Years After Severe Poliomyelitis

Dyspnea in a Patient Years After Severe PoliomyelitisNeuromuscular disease or upper airway obstruction can present with breathlessness on exertion. Routine physiologic studies such as spirometry or maximum voluntary ventilation (MW) may provide clues to their presence but unfortunately often give similar results making it difficult to separate the contribution of these diseases. Cardiopulmonary exercise testing (CPET) has been used in the evaluation of patients with dyspnea, but most of these studies have been in patients with cardiac disease, chronic airflow obstruction (CAO), or pulmonary parenchymal disorders. There are few reports of exercise studies in patients with tracheal stenosis or in patients with neuromuscular disease. The following case demonstrates the utility of CPET in discerning the cause of dyspnea in a patient who suffered from both neuromuscular respiratory disease and upper airway obstruction following remote poliomyelitis.
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The Effect of Radiation Therapy on Immune Function in Patients With Squamous Cell Lung Carcinoma – Conclusion

The Effect of Radiation Therapy on Immune Function in Patients With Squamous Cell Lung Carcinoma - ConclusionWe also found that the lymphoblast transformation induced by PHA or PPD was depressed after RT. This suggested that RT directly influenced the functions of lymphocytes and monocytes. Since the compositions of PBMC used for lymphoblast transformation before and after RT were not different, we could exclude the possible influence of different cellular compositions on the lymphoblast transformation by these stimulants.
Because monocytes are essential for lymphocytes to proliferate by mitogens or antigens, the functional defects in monocytes as well as in lymphocytes may contribute to the depressed lymphoblast transformation by PHA and PPD after RT. To dissect the functional changes in peripheral lymphocytes and monocytes, an analysis using purely separated lymphocytes and monocytes is preferable. However abnormal function of purely separated lymphocytes does not always mean normal function of monocytes. mycanadianpharmacy

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