Elastic Cuff Research Articles

Safety Notice for the Use of Drugs for Intravesical Instillations and Cost Analysis

Among the objectives outlined in the National Health Plan 1998-2000 are some interventions to improve the safety of public and private health-care facilities. One of the significant risks in the health sector is the one resulting from exposure to chemotherapy drugs. The Health Surveillance must take into account that anticancer drugs are cytotoxic compounds, which can cause cancer. It is necessary that occupational exposure to antineoplastic agents be kept within the lowest possible level. The potential absorption due to exposure to chemotherapy may be significantly reduced by adopting preventive measures specific to particular concern in a centralization of structures and activities. To ensure an adequate system of protection for people who use these substances in professional health-care settings, there should be the establishment of a specific "Anticancer Drugs Unit" to entrust the working cycle. The places reserved for the preparation of cytotoxic chemotherapy must be equipped with floor and walls up to heights of appropriate plastic material easily washable. Inside the room there must be a "point of decontamination" for washing hands and eyes. The preparation of antineoplastic agents should be performed under hoods positioned away from heat sources and any air currents. It is advisable to use disposable surgical gowns with long sleeves with elastic cuffs or knitted sleeve to allow the gloves sticking above the gown itself. In the preparation of drugs the vial opening procedure must be implemented after verifying that no liquid is left at the top, and by wrapping the neck of the vial with a sterile gauze. Any accidental contamination must be reported to the Physician. All waste materials produced from the handling of cytotoxic chemotherapy should be considered as special hospital waste. To achieve high standards of safety and prevention for the personnel exposed to antineoplastic agents, it is necessary that workers are adequately informed about the risks and proper handling and disposal of anticancer drugs and contaminated materials.

Effects of high-intensity and blood flow-restricted low-intensity resistance training on carotid arterial compliance: role of blood pressure during training sessions

We examined the effects of high-intensity resistance training (HIT) and low-intensity blood flow-restricted (LI-BFR) resistance training on carotid arterial compliance. Nineteen young men were randomly divided into HIT (n = 9) or LI-BFR (n = 10) groups. The HIT and LI-BFR groups performed 75 and 30 %, respectively, of one-repetition maximum (1-RM) bench press exercise, 3 days per week for 6 weeks. During the training sessions, the LI-BFR group wore elastic cuffs around the most proximal region of both arms. Muscle cross-sectional area (CSA), 1-RM strength, and carotid arterial compliance were measured before and 3 days after the final training session. Acute changes in systolic arterial pressure (SAP), plasma endothelin-1 (ET-1), nitrite/nitrate (NOx), and noradrenalin concentrations were also measured during and after a bout of training session. The training led to significant increases (P < 0.01) in bench press 1-RM and arm and chest muscle CSA in the two training groups. Carotid arterial compliance decreased significantly (P < 0.05) in the HIT group, but not in the LI-BFR group. There was a significant correlation (r = -0.533, P < 0.05) between the change in carotid arterial compliance and the acute change in SAP during training sessions; however, ET-1 and NOx did not correlate with carotid arterial compliance. Our results suggest that muscle CSA and strength increased following 6 weeks of both HIT and LI-BFR training. However, carotid arterial compliance decreased in only the HIT group, and the changes were correlated with SAP elevations during exercise sessions.

Cardiovascular and perceptual responses to blood‐flow‐restricted resistance exercise with differing restrictive cuffs

The purpose of this study was to determine (i) the cardiovascular responses to acute blood-flow-restricted (BFR) resistance exercise and (ii) the influence of applied BFR cuff type on the cardiovascular and perceptual responses. In a randomized, crossover design, 27 participants wore either a 5·0cm wide elastic cuff or a 13·5cm wide non-elastic cuff around the thigh while performing four sets of knee extension exercise using 20% of 1-RM. Brachial and central blood pressure (BP) and aortic augmentation index (AIx) were measured before and after the restrictive cuffs were applied and inflated, after the 2nd and 4th set of resistance exercise, and 5 and 15min following the 4th set of exercise. Ratings of perceived exertion and pain were obtained before exercise and after the 2nd and 4th set of exercise. Both brachial and central BPs increased and AIx decreased during BFR exercise but returned to baseline levels within 15min following exercise. The wide cuffs caused a greater elevation in heart rate, brachial and central BPs, perceived effort and pain and a greater decrease in AIx during the BFR exercise. These findings suggest that low-intensity BFR resistance exercise does not appear to acutely negatively affect the vasculature. Also, cuff type will greatly affect cardiovascular and perceptual responses to BFR resistance exercise and thus is an important consideration in study design.

Relationship between limb and trunk muscle hypertrophy following high‐intensity resistance training and blood flow–restricted low‐intensity resistance training

We examined the relationship between training-induced limb and trunk muscle hypertrophy in high-intensity resistance training (HIT) or blood flow-restricted low-intensity resistance training (LI-BFR) programmes. Thirty young men were divided into three groups: HIT (n = 10), LI-BFR (n = 10) and non-training control (CON, n = 10). The HIT and LI-BFR groups performed 75% and 30%, respectively, of one-repetition maximal (1-RM) bench press exercise, 3 days per week for 6 weeks. During the training sessions, the LI-BFR group wore elastic cuffs around the most proximal region of both arms. Muscle cross-sectional area (CSA) and 1-RM bench press strength were measured before and 3 days after the final training session. Total training volumes (lifting weight × number of repetitions) for all of the sessions were similar between the two training groups. The training led to a significant increase (P < 0·05) in bench press 1-RM in the two training groups, but not in the CON group. Triceps brachii and pectoralis major muscle CSA increased 8·8% and 15·8% (P < 0·01), respectively, in the HIT group and 4·9% (P < 0·05) and 8·3% (P < 0·01), respectively, in the LI-BFR group, but not in the CON group (-1·1% and 0·0%, respectively). There was significant correlation (r = 0·70, P < 0·05) between increases in triceps brachii and pectoralis major muscle CSA in the HIT group; however, the correlation was lower and non-significant in the LI-BFR group (r = 0·54). Our results suggest that limb and trunk muscle hypertrophy occurs simultaneously during HIT but not during LI-BFR, possibly owing to individual differences in activation of the arm and chest muscles during the training sessions.

Effects of low‐intensity bench press training with restricted arm muscle blood flow on chest muscle hypertrophy: a pilot study

Single-joint resistance training with blood flow restriction (BFR) results in significant increases in arm or leg muscle size and single-joint strength. However, the effect of multijoint BFR training on both blood flow restricted limb and non-restricted trunk muscles remain poorly understood. To examine the impact of BFR bench press training on hypertrophic response to non-restricted (chest) and restricted (upper-arm) muscles and multi-joint strength, 10 young men were randomly divided into either BFR training (BFR-T) or non-BFR training (CON-T) groups. They performed 30% of one repetition maximal (1-RM) bench press exercise (four sets, total 75 reps) twice daily, 6 days week(-1) for 2 weeks. During the exercise session, subjects in the BFR-T group placed elastic cuffs proximally on both arms, with incremental increases in external compression starting at 100 mmHg and ending at 160 mmHg. Before and after the training, triceps brachii and pectoralis major muscle thickness (MTH), bench press 1-RM and serum anabolic hormones were measured. Two weeks of training led to a significant increase (P<0.05) in 1-RM bench press strength in BFR-T (6%) but not in CON-T (-2%). Triceps and pectoralis major MTH increased 8% and 16% (P<0.01), respectively, in BFR-T, but not in CON-T (-1% and 2%, respectively). There were no changes in baseline concentrations of anabolic hormones in either group. These results suggest that BFR bench press training leads to significant increases in muscle size for upper arm and chest muscles and 1-RM strength.

Trach tubes designed to maximize safety may increase risk to ventilated patients

Dual-cannulae tracheostomy tubes with low-pressure cuffs, such as the Shiley LPC, are widely regarded as inherently safer than single lumen tubes with low-volume cuffs. For the patient who undergoes tracheostomy for failure to wean from mechanical ventilation, however, the insertion of a tube that occupies a large amount of space within the trachea can delay subsequent efforts to liberate him from the ventilator. With an aim to promote more timely rehabilitation of ventilated patients, London Ontario's University Hospital has been inserting the Bivona TTS, a single lumen tube with an elastic cuff, during tracheostomy. This allows caregivers to better exploit the benefits of a functional upper airway early during the weaning process, which may reduce complications associated with prolonged mechanical ventilation. We urge clinical studies to determine how the choice of initial tracheostomy tube can affect rehabilitation strategies and important patient outcomes.

Non-invasive determination of instantaneous brachial blood flow using the oscillometric method

The oscillometric method has been widely used to measure arterial systolic and diastolic blood pressures, but its potential for arterial blood flow measurements still remains to be explored. The aim of this study was to non-invasively determine arterial blood flow using an oscillometric blood flow measurement system. The system consists of a pneumatic elastic cuff, an air-pumping motor, a releaser valve, a pressure transducer, and an airflow meter. To build a non-linear cuff model, we measured airflow pumped into the pneumatic cuff and cuff pressure using an airflow meter and pressure transducer during the inflation period, respectively. During the deflation period, only the pressure transducer was used to record cuff pressure. Based on the cuff model, the oscillometric blood flow waveform was obtained by integrating the oscillometric pressure waveform. We compared arterial blood flow derived from the maximum amplitude of the oscillometric blood flow waveform with Doppler-measured blood flow calculated with the diameters and blood velocities of the brachial arteries in 32 subjects who underwent diagnostic evaluations for peripheral arterial embolism. A linear correlation coefficient of r = 0.716 was found between the oscillometry- and Doppler-based blood flow measurements in the 32 subjects. These results suggest that blood flow passing through the brachial artery can be quantified non-invasively using the oscillometric approach after appropriate calibration.

Venous Blood Changes with Low-Intensity Muscle Contractions and Blood Flow Restriction

Work output during repetitive low-intensity muscle contractions is presumably maintained by increased motor unit recruitment (increased EMG activity) during restricted blood flow. Interestingly, the increased muscle activation is associated with an increased oxygen uptake (Vo2); an unexpected finding given the same external work and reduced muscle blood flow. PURPOSE: To investigate changes in venous blood metabolites and gases during repetitive muscle contractions with restricted blood flow. METHODS: Six male volunteers performed 3 trials (separated by 1-week) of unilateral elbow flexion muscle contractions (20% of 1-RM; 30 repetitive contractions then 3 sets of 15 contractions, 30 sec rest between sets). Contractions were performed with unrestricted blood flow (C) or two levels of blood flow restriction using a KAATSU belt; a specially designed elastic cuff placed at the most proximal position of the upper arm and inflated to either 100 (K100) or 160 (K160) mmHg to restrict blood flow. Venous blood was collected prior to contractions and following the 30 repetitive contractions and the last set of 15 contractions; (an indwelling catheter inserted in the brachial vein below the cuff). Venous blood was analyzed using a blood gas analyzer (Instrumentation Laboratory, Japan). RESULTS: Oxygen saturation decreased with contractions in all trials (P<0.05) with K160 (33% and 34%, respectively) being greater than K100 (41% and 42%, respectively) and both greater than C (67% and 56%, respectively). Changes in venous blood pH and PCO2 were greater in K160 than K100 and C. Venous PO2 decreased similarly in K160 and K100, significantly less than C. Hematocrit and [glucose] were similar in all trials while [lactate] was greater (P<0.05) in K160 (4.4 and 5.6 mmol/L, respectively) than K100 (3.2 and 3.6 mmol/L, respectively) and C (2.5 and 2.9 mmol/L, respectively). CONCLUSION: The significant reduction in oxygen saturation supports the previously observed increase in VO2 during blood flow restriction. The basis for the greater lactate concentration is unknown; either increased production or reduced removal. These data appear to support the conclusion that energy supply is paradoxically increased during low-intensity muscle contractions with restricted blood flow, likely associated with increased muscle activation.

A double-layer tracheal tube cuff designed to prevent leakage: a bench-top study

We designed a new endotracheal tube (ETT) cuff that does not form the folds that cause leakage of colonized subglottic secretions upon inflation within the trachea: a standard high-volume low-pressure cuff was draped with a second, highly elastic cuff made of a low-protein guayule natural latex rubber with 0.5 ml gel between the cuffs. We compared this prototype ETT cuff with four commercially available ETTs for efficacy in the prevention of fluid leakage across the cuff. In vitro study. We compared fluid leakage in our prototype cuff with that in four commercially available ETTs. Three cylindrical glass tubes 16, 20, and 22 mm in diameter were used as model tracheas, and five different intracuff pressures (20, 25, 30, 40, and 50 cmH(2)O) were tested. Each test was repeated three times with new ETTs. The guayule latex ETT cuff showed an average fluid leakage of 0.0007 +/- 0.002 ml/min which was significantly lower than that in any of the other ETTs (Microcuff 0.07 +/- 0.09, Mallinckrodt/Hi-Lo Evac 5 +/- 5, Euromedical 7 +/- 4, Sheridan/CF 41 +/- 69). Our prototype ETT cuff significantly reduced fluid leakage in this bench-top study. In vivo testing and evaluation is to follow.

Development of an Implantable Pulse Oximeter

A long-term implantable photoplethysmographic sensor system is proposed. The system employs an elastic cuff which is directly wrapped around an arterial blood vessel. The optically transparent cuff is equipped with light emitting diodes and a photo transistor including the technology of pulse oximetry. The sensor will permit real-time, continuous monitoring of important vital parameters such as arterial blood oxygen saturation and pulse rate over a long-term period in vivo. We emphasize on the specific requirements for design and instrumentation of the implantable sensor and discuss first in vitro data acquired with that new photonics-based sensor.

Invasive ductal adenocarcinoma of the pancreas may originate from the larger pancreatic duct: a study of 13 tumors less than 2 cm in diameter

We aimed to elucidate the origin/primary site of invasive ductal adenocarcinoma of the pancreas, based on the distribution of intraductal carcinoma components. These components were identified by a mural elastic fiber cuff. Thirteen specimens from patients with invasive ductal adenocarcinoma (microscopically, less than 2 cm in diameter) of the pancreas were studied histopathologically. Variants of invasive ductal adenocarcinoma and intraductal papillary-mucinous carcinoma were excluded. Intraductal carcinoma components of invasive ductal adenocarcinoma were found in 12 of the specimens 13 (92%), and were observed within the tumor mass and/or on its boundary, or outside the tumor mass. Intraductal components were characterized by low papillary projections lacking a fibrovascular core, with/without surrounding tubular structures, or by irregular stratification and pleomorphism of the epithelial cells. Invasive components mostly showed a tubular pattern with desmoplasia. The distribution of the intraductal components in the 12 specimens was as follows: in 9 (75%), they were in both the main pancreatic duct and large branch ducts; and in 3, they were in the smaller branch ducts only. Invasive ductal adenocarcinomas of the pancreas may originate most frequently from the main pancreatic duct or larger branch ducts, while the smaller ducts are less often the site of cancer origin.

Comparison of EMG activity among Low-intensity Exercise with and without KAATSU and Ischemic Conditions

It is established that electromyographic (EMG) activity increases during ischemia with low-intensity exercise compared with normal conditions. Since low-intensity (20% of one repetition maximum, 1 -RM) exercise combined with restricted venous blood flow (KAATSU) produced substantial muscle hypertrophy and strength gain, we hypothesized that EMG activity in working muscle could be increased during low-intensity KAATSU exercise. PURPOSE: To compare the magnitude changes in EMG activity during low-intensity exercise with and without KAATSU and ischemic conditions. METHODS: Seven male volunteers [mean (SD) age: 24.9 (3.3) years] performed two modes (3 sets of 10 reps with 30 sec rest between sets and 30 consecutive reps) of single arm curl exercise (20% of a predetermined 1-RM) during three different conditions (Control, KAATSU and Ischemia). In the KAATSU condition, a specially designed elastic cuff belt (30 mm wide) was placed at the most proximal position of the upper arm and inflated to a pressure of 30% higher than their systolic blood pressure. During the ischemic condition, blood flow was occluded by over 300 mmHg of occlusive pressure via occlusion cuff. Surface EMG was recorded from muscle belly of the biceps brachii muscle, and mean integrated EMG (iEMG) was analyzed. RESULTS: During 3 sets of 10 reps exercise, a gradual increase (P < 0.01) in iEMG was observed in Ischemia but not in both KAATSU and Control. The magnitude increase in iEMG was higher (P < 0.01) in Ischemia (101% higher at end of 3 sets) compared with KAATSU (52%) and Control (23%). On the other hand, there was similar increase in iEMG between Ischemia (92%) and KAATSU (78%) during 30 consecutive reps of exercise, and both conditions were higher (P < 0.05) than that of Control (40%). After 30 consecutive reps of exercise, both KAATSU and Control conditions performed additional sets of exercise (3 sets of 15 reps with 30 sec rest between sets). At the end of 3 sets of 15 reps, the increase in iEMG was 244% for KAATSU and 86% for Control. The increase in iEMG was larger (P < 0.01) in KAATSU compared with Control. CONCLUSION:Increase in iEMG during KAATSU may be an important factor for KAATSU training-induced muscle hypertrophy and strength gain.

Electromyographic responses of arm and chest muscle during bench press exercise with and without KAATSU

The purpose of this study was to compare the EMG activity of blood flow restricted (limb) and nonrestricted (trunk) muscles during multi-joint exercise with and without KAATSU. Twelve (6 women and 6 men) healthy college students [means (SD) age: 24.1 (3.5) yrs] performed 4 sets (30, 15, 15, and 15 reps) of flat bench press exercise (30% of a predetermined one repetition maximum, 1-RM) during two different conditions [with KAATSU and without KAATSU (Control)]. In the KAATSU condition, a specially designed elastic cuff belt (30 mm wide) was placed at the most proximal position of the upper arm and inflated to a pressure of 100% of individual's resting systolic blood pressure. Surface EMG was recorded from the muscle belly of the triceps brachii (TB) and pectoralis major (PM) muscles, and mean integrated EMG (iEMG) was analyzed. During 4 sets of the exercise, gradual increases in iEMG were observed in both TB and PM muscles for the KAATSU condition. The magnitude of the increases in iEMG in the TB and PM muscles were higher (P<0.05) with KAATSU compared to the Control condition. In the first set, the mean exercise intensity from normalized iEMG was approximately 40% of 1-RM in both Control and KAATSU conditions. However, the mean exercise intensity of both muscles were 60-70% of 1-RM for the KAATSU condition and only about 50% of 1-RM for the Control condition, respectively, during the fourth set. We concluded that increases in iEMG in the trunk muscle during KAATSU might be an important factor for KAATSU training-induced trunk muscle hypertrophy.

Tracheostomy Tube Enabling Speech During Mechanical Ventilation

A voice tracheostomy tube (VTT) was developed to enable patients to speak during mechanical ventilation. The VTT has slits cut in it and is covered on part of its side with an elastic cuff, enabling the cuff to expand with positive pressure from the ventilator on inspiration and to deflate on expiration. By this mechanism, inspired air from the ventilator goes to the lung with the cuff inflated, and some of the expired air passes out around the deflated cuff and discharges through the glottis, allowing sufficient ventilation and also enabling vocal fold vibration. An experiment using a model lung showed that there was little leakage on inspiration even for low lung compliance and high airway pressure, and that the leakage volume on expiration was approximately 40% of the ventilated volume, ie, the volume discharging through the vocal fold in clinical use. Sixteen patients who had been managed by ventilation via a conventional tracheostomy tube were switched to the VTT. All patients except one were able to speak after switching to the VTT without change in PaO(2) and PaCO(2). There were no complications associated with the use of the VTT. Bronchoscopy showed that the cuff of the VTT did not damage the tracheal mucosa. The VTT enables patients to speak during mechanical ventilation with sufficient ventilation and without aspiration and damage to the tracheal mucosa, even in patients with low lung compliance.

Pressure support and elevation following the removal of a radial artery for coronary artery bypass grafting

The saphenous vein was once the standard coronary artery bypass graft. Alternate grafts, primarily the radial artery and the internal mammary artery are now being utilised for revascularisation of the heart. However, the radial artery graft site can be at risk of oedema and the development of haematoma during the post-operative period. Also tension on the suture line may compromise circulation and create functional problems for the patient. The aim of this study was to assess the effect of pressure support (elastic support bandage) and elevation in reducing swelling and arm discomfort in the harvest arm. The patients in the study undergoing coronary artery bypass grafts were randomly assigned to one of three groups: elastic support bandage, collar and cuff sling and elevation on two pillows. There were 30 patients in each group. The circumference at three locations on the forearm was measured pre-operatively and on post-operative days 3 and 5. Pain was measured on a visual pain scale, which went from 1-10, with 10 being the most painful. The patients were also asked whether their arm movement felt restricted. The study found that there was no statistically significant difference (at the 0.05 level) between the three groups in the amount of swelling witnessed at the different forearm locations. There was, however, a significant decrease in swelling for all groups between days 3-5, but no difference in pain scores between the groups. Moreover, the collar and cuff sling group reported movement restriction, which was not apparent in the other two groups. In view of the findings, the researchers advocate the elastic support bandage. Patient compliance has practical implications when applying treatment and this is enhanced by the non cumbersome elastic support bandage. This can be compared to the collar and cuff sling and pillow elevation groups where the patient's daily activities affects compliance with these two treatments. It is recommended that future research be conducted comparing the effects of the elastic support bandage with a control group.

90th Anniversary of the Development by Nikolai S. Korotkoff of the Auscultatory Method of Measuring Blood Pressure

Every day, all over the world, many thousands of physicians, nurses, and paramedics measure systemic arterial pressure by applying a cuff with an inflatable bladder around the patient's arm and using a stethoscope to listen to the sounds in the brachial artery. Many care providers know that they are listening to “Korotkoff sounds,” but very few know that the method was introduced 90 years ago by a Russian doctor and scientist, Nikolai Sergeevich Korotkoff (Fig 1⇓). Indeed, a report on a new method of measurement of arterial pressure1 was presented on November 8, 1905, at a scientific seminar of the Imperial Military Medical Academy, Saint Petersburg, Russia, by Korotkoff, a young surgeon from the clinic of Prof Sergei P. Fedorov. (The authors found the date of the presentation mentioned in Korotkoff's dissertation.2(p116)) An English translation of the text of Korotkoff's presentation1 was published by W.H. Lewis, Jr, in 1941.3 In the 90 years since Korotkoff presented the new method to measure the arterial pressure, medical science and medical technology have made big strides. However, because of its simplicity and high degree of accuracy, the method of auscultatory measurement of arterial pressure remains the most acceptable in everyday medical practice. Moreover, this method is one of only a few techniques for clinical examination of patients that has not undergone significant changes since it was introduced. Very little is known, even in his native Russia, about the life and work of this doctor and scientist.4 Outside Russia, even less is known about Korotkoff. Some biographical information by Segall was published in English in 1965.5 However, because of differences between the Russian and American systems of education, Segall misinterpreted some facts of Korotkoff's life. Information in the present article was based on materials available in the …

Hydrostatic inflation for low-pressure tracheal cuffs.

To the Editor.— Recently published data in dogs 1 demonstrated the superiority of low-pressure endotracheal tube cuffs over high-pressure conventional endotracheal cuffs. Low-pressure cuffs decrease the incidence of superficial mucosal ulceration, and eliminate necrosis of deep-lying tracheal structures, seen occasionally after prolonged intubation with high-pressure cuffs. A technical problem exists, however, in the clinical application of these cuffs: proper inflation is difficult to achieve. Too much air introduced into the cuff can defeat the purpose of the low-pressure design, ie, to have a cuff which seals with a minimal pressure on the tracheal mucosa. Too much air also can herniate elastic cuffs over the end of the tube causing airway obstruction. Cuff rupture can also occur. Because the cuffs are so compliant, it is difficult to determine an end point for inflation unless relatively complex pressure gauges, sensitive in the lowpressure range (10 to 30 cm H 2 O) are

The influence of the method of compression on the value of the terminal maximal intra-arterial pressure

The terminal maximal intra-arterial pressure was determined in the tail arteries of dogs with the aid of an elastic cuff, concentric capsule and a device for exerting local pressure on the vessel. Different compression devices were used separately and in pairs, with the change of their location on the tail in conformity with the difference in the thickness of soft tissues subjected to compression. It was experimentally demonstrated that the compression measurement of the terminal maximal blood pressure is accompanied by some exaggeration of the data received. This exaggeration is connected with the resistance of the soft tissues, the extent of which depends on the method of compression.

Sutureless Reunion of Severed Nerves with Elastic Cuffs of Tantalum

Sutureless Reunion of Severed Nerves with Elastic Cuffs of Tantalum