There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particul... more There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particular on how to set the tourniquet pressure, how to select the most appropriate cuff, and whether to use some type of soft padding beneath the cuff for limb protection. The authors could find only one published study specifically addressing pediatric cuff pressures, and no studies showing what types of cuff and/or padding create the smoothest skin surface under the cuff. Of 46 pediatric orthopaedic surgeons surveyed, 44 use a tourniquet 4.6 times per week on average and 2 have discontinued their use as a result of complications. To set cuff pressure, 13 of 44 use a standard value, 14 of 44 base pressure on age, extremity, and size, and 17 of 44 base cuff pressure on blood pressure. Thirty-four of 44 use skin protection under the cuff, but damage to the skin is common, accounting for 21 of the 67 reported complications. Nerve (15/67) and muscle (8/67) complications, related to both pressure and tourniquet time, were also reported.
Pneumatic tourniquets are used many thousands of times per day in orthopaedic and non-orthopaedic... more Pneumatic tourniquets are used many thousands of times per day in orthopaedic and non-orthopaedic surgical procedures throughout the world, facilitating operations by reliably establishing a bloodless surgical field with a high level of safety. Within the last thirty years, there have been important improvements in the technology of tourniquet instruments and tourniquet cuffs, leading to greater safety and efficacy in surgical procedures and non-surgical settings. This paper provides an overview of current concepts in tourniquets in the following six areas: 1) Safety features integrated into modern tourniquet systems; 2) The use of Limb Occlusion Pressure (LOP) to enable individualized, optimal tourniquet pressure settings to be achieved; 3) Personalization of tourniquet cuffs through the use of variable contour design and availability of cuffs to fit pediatric and bariatric patient populations; 4) Reduction of soft tissue injuries through the use of limb protection sleeves matched ...
Rehabilitation of wounded warriors, professional athletes and orthopaedic patients has profound h... more Rehabilitation of wounded warriors, professional athletes and orthopaedic patients has profound health, economic, psychological, and social implications. This has motivated development and investigation of a new technique, Personalized Blood Flow Restriction Training (PBFRT), which may substantially reduce recovery time and improve rehabilitation. PBFRT involves exercising well below maximum intensity using an optimal personalized restrictive pressure (PRP) in a tourniquet cuff encircling a limb, for brief and repeated exercise periods according to a rehabilitation protocol. Although the exact mechanism is not fully understood, many studies have shown beneficial effects of blood flow restricted training on skeletal muscle strength and hypertrophy, and preliminary evidence suggests it may also promote bone formation. Advances in the development of modern tourniquet systems made within our group in Canada allow PBFRT to be performed with optimal safety and repeatability, establishing ...
Background Development of automatic, pneumatic tourniquet technology and use of personalised tour... more Background Development of automatic, pneumatic tourniquet technology and use of personalised tourniquet pressures has improved the safety and accuracy of surgical tourniquet systems. Personalisation of tourniquet pressure requires accurate measurement of limb occlusion pressure (LOP), which can be measured automatically through two different methods. The ‘embedded LOP’ method measures LOP using a dual-purpose tourniquet cuff acting as both patient sensor and pneumatic effector. The ‘distal LOP’ method measures LOP using a distal sensor applied to the patient’s finger or toe of the operating limb, using photoplethysmography to detect volumetric changes in peripheral blood circulation. The distal LOP method has been used clinically for many years; the embedded LOP method was developed recently with several advantages over the distal LOP method. While both methods have clinically acceptable accuracy in comparison to LOP measured using the manual Doppler ultrasound method, these two aut...
There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particul... more There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particular on how to set the tourniquet pressure, how to select the most appropriate cuff, and whether to use some type of soft padding beneath the cuff for limb protection. The authors could find only one published study specifically addressing pediatric cuff pressures, and no studies showing what types of cuff and/or padding create the smoothest skin surface under the cuff. Of 46 pediatric orthopaedic surgeons surveyed, 44 use a tourniquet 4.6 times per week on average and 2 have discontinued their use as a result of complications. To set cuff pressure, 13 of 44 use a standard value, 14 of 44 base pressure on age, extremity, and size, and 17 of 44 base cuff pressure on blood pressure. Thirty-four of 44 use skin protection under the cuff, but damage to the skin is common, accounting for 21 of the 67 reported complications. Nerve (15/67) and muscle (8/67) complications, related to both pressure and tourniquet time, were also reported.
Images of the Twenty-First Century. Proceedings of the Annual International Engineering in Medicine and Biology Society
ABSTRACT A prerobotic positioning system for retractors was developed to replace and improve upon... more ABSTRACT A prerobotic positioning system for retractors was developed to replace and improve upon the manual techniques and mechanical apparatus that are now commonly used during surgical procedures. The system is a lightweight, pneumatically powered, electronically controlled positioner having ball joints between the three members. The combination of ball joints and 90° bent connecting shafts provides a versatile spherical geometry whereby redundant methods exist to achieve the same position of the end effector, thereby allowing the surgeon to avoid intermediate obstacles during setup and use. Besides being easy to control and position, the device's major advantage is a predictable and reliable locking strength of the ball joints (minimum 25 ft-lb at 100 psi)
There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particul... more There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particular on how to set the tourniquet pressure, how to select the most appropriate cuff, and whether to use some type of soft padding beneath the cuff for limb protection. The authors could find only one published study specifically addressing pediatric cuff pressures, and no studies showing what types of cuff and/or padding create the smoothest skin surface under the cuff. Of 46 pediatric orthopaedic surgeons surveyed, 44 use a tourniquet 4.6 times per week on average and 2 have discontinued their use as a result of complications. To set cuff pressure, 13 of 44 use a standard value, 14 of 44 base pressure on age, extremity, and size, and 17 of 44 base cuff pressure on blood pressure. Thirty-four of 44 use skin protection under the cuff, but damage to the skin is common, accounting for 21 of the 67 reported complications. Nerve (15/67) and muscle (8/67) complications, related to both pressure and tourniquet time, were also reported.
Pneumatic tourniquets are used many thousands of times per day in orthopaedic and non-orthopaedic... more Pneumatic tourniquets are used many thousands of times per day in orthopaedic and non-orthopaedic surgical procedures throughout the world, facilitating operations by reliably establishing a bloodless surgical field with a high level of safety. Within the last thirty years, there have been important improvements in the technology of tourniquet instruments and tourniquet cuffs, leading to greater safety and efficacy in surgical procedures and non-surgical settings. This paper provides an overview of current concepts in tourniquets in the following six areas: 1) Safety features integrated into modern tourniquet systems; 2) The use of Limb Occlusion Pressure (LOP) to enable individualized, optimal tourniquet pressure settings to be achieved; 3) Personalization of tourniquet cuffs through the use of variable contour design and availability of cuffs to fit pediatric and bariatric patient populations; 4) Reduction of soft tissue injuries through the use of limb protection sleeves matched ...
Rehabilitation of wounded warriors, professional athletes and orthopaedic patients has profound h... more Rehabilitation of wounded warriors, professional athletes and orthopaedic patients has profound health, economic, psychological, and social implications. This has motivated development and investigation of a new technique, Personalized Blood Flow Restriction Training (PBFRT), which may substantially reduce recovery time and improve rehabilitation. PBFRT involves exercising well below maximum intensity using an optimal personalized restrictive pressure (PRP) in a tourniquet cuff encircling a limb, for brief and repeated exercise periods according to a rehabilitation protocol. Although the exact mechanism is not fully understood, many studies have shown beneficial effects of blood flow restricted training on skeletal muscle strength and hypertrophy, and preliminary evidence suggests it may also promote bone formation. Advances in the development of modern tourniquet systems made within our group in Canada allow PBFRT to be performed with optimal safety and repeatability, establishing ...
Background Development of automatic, pneumatic tourniquet technology and use of personalised tour... more Background Development of automatic, pneumatic tourniquet technology and use of personalised tourniquet pressures has improved the safety and accuracy of surgical tourniquet systems. Personalisation of tourniquet pressure requires accurate measurement of limb occlusion pressure (LOP), which can be measured automatically through two different methods. The ‘embedded LOP’ method measures LOP using a dual-purpose tourniquet cuff acting as both patient sensor and pneumatic effector. The ‘distal LOP’ method measures LOP using a distal sensor applied to the patient’s finger or toe of the operating limb, using photoplethysmography to detect volumetric changes in peripheral blood circulation. The distal LOP method has been used clinically for many years; the embedded LOP method was developed recently with several advantages over the distal LOP method. While both methods have clinically acceptable accuracy in comparison to LOP measured using the manual Doppler ultrasound method, these two aut...
There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particul... more There are few clear guidelines on the proper use of tourniquets in pediatric surgery, in particular on how to set the tourniquet pressure, how to select the most appropriate cuff, and whether to use some type of soft padding beneath the cuff for limb protection. The authors could find only one published study specifically addressing pediatric cuff pressures, and no studies showing what types of cuff and/or padding create the smoothest skin surface under the cuff. Of 46 pediatric orthopaedic surgeons surveyed, 44 use a tourniquet 4.6 times per week on average and 2 have discontinued their use as a result of complications. To set cuff pressure, 13 of 44 use a standard value, 14 of 44 base pressure on age, extremity, and size, and 17 of 44 base cuff pressure on blood pressure. Thirty-four of 44 use skin protection under the cuff, but damage to the skin is common, accounting for 21 of the 67 reported complications. Nerve (15/67) and muscle (8/67) complications, related to both pressure and tourniquet time, were also reported.
Images of the Twenty-First Century. Proceedings of the Annual International Engineering in Medicine and Biology Society
ABSTRACT A prerobotic positioning system for retractors was developed to replace and improve upon... more ABSTRACT A prerobotic positioning system for retractors was developed to replace and improve upon the manual techniques and mechanical apparatus that are now commonly used during surgical procedures. The system is a lightweight, pneumatically powered, electronically controlled positioner having ball joints between the three members. The combination of ball joints and 90° bent connecting shafts provides a versatile spherical geometry whereby redundant methods exist to achieve the same position of the end effector, thereby allowing the surgeon to avoid intermediate obstacles during setup and use. Besides being easy to control and position, the device's major advantage is a predictable and reliable locking strength of the ball joints (minimum 25 ft-lb at 100 psi)
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