Garg Autologous Blood Concentrates

Second Edition
2. Auflage 2021
ISBN: 978-1-64724-084-4
Verlag: Quintessence Publishing Co, Inc
Format: EPUB
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 184 Seiten

Since its discovery over two decades ago, platelet-rich plasma (PRP) and its derivatives have become a mainstay in oral and maxillofacial surgery and, more recently, in other dental specialties as well. As technology continues to allow significant innovation in this field, more and more formulations and products are being discovered and marketed to dentists. In the second edition of this bestselling book, Dr Garg sheds the salesmanship that often swirls around PRP and instead focuses on the science, biology, and clinical applications of this natural biomaterial. Credited as a co-discoverer of PRP, he knows how to break down the science and explain how autologous blood concentrates work to speed healing and promote tissue regeneration. This natural, inexpensive, and safe material has enormous potential in a dental clinic, and Dr Garg wants to make sure every clinician has access to information that is easy to digest and easy to apply. This book is thereby a roadmap to incorporating autologous blood concentrates into clinical practice. The early chapters focus on the biology of what goes on when blood is collected and centrifuged and reintroduced into wound sites as well as how to prepare the different formulations of autologous blood concentrates. The later chapters demonstrate how to use this material in implant surgery, soft and hard tissue healing, facial cosmetics, and other clinical applications to achieve superb outcomes. With a bonus chapter on phlebotomy, this book is the practical manual novices need and experienced clinicians value.

Arun K. Garg, DMD, served as a full-time professor of surgery and director of residency training in the Division of Oral and Maxillofacial Surgery at the University of Miami School of Medicine for nearly 20 years, where he received multiple Faculty Member of the Year awards. He has authored more than a 8 textbooks and over 150 scientific journal articles. He has trained thousands of dentists and dental specialists over the course of his career. Since 2006, he has devoted much of his time and energy to educating and training clinicians on bone grafting and dental implant surgery through Implant Seminars Inc, a company he founded. In addition, he maintains several private practices throughout South Florida. An early adopter and proponent of using dermal fillers and Botox to complement cosmetic dental treatments, in 2011, he cofounded DentaSpa Seminars, which provides education and clinical training in facial rejuvenation procedures designed specifically for dental practitioners.

Autoren/Hrsg.

Garg, Arun K.

Leseproben

2

Medical and Surgical Applications of Autologous Blood Concentrates

The literature on PRP demonstrates the diversity of its clinical applications. Separate chapters in this text are devoted to clinical uses of PRP in plastic surgery and in oral, periodontal, and maxillofacial surgeries. Separate chapters are required because, for example in plastic surgery, there is a lengthy history of topical use of a variety of forms of platelet concentrates for skin wound healing, and there is a rapidly growing popularity of PRP use for esthetic and cosmetic purposes.1,2 There is a similarly lengthy history of various forms of PRP being used in a variety of periodontal and dentoalveolar procedures as well as in bone grafting, implant surgery, and reconstructive surgery.3,4

Since its first surgical application in the late 1980s for autologous transfusion support in open-heart procedures, PRP has been used in a variety of clinical settings because of its ability to enhance tissue repair and healing at wound sites.5 In April 2015, the National Center for Biotechnology Information listed more than 280 books, over 7,700 scientific and medical abstractions/citations, and more than 21,400 full-text journal articles on PRP, in a wide variety of fields, including cardiothoracic surgery, cosmetics, dentistry, maxillofacial surgery, neurosurgery, ophthalmology, orthopedics, otolaryngology, sports medicine, urology, and wound healing.

The application of PRP at wound sites is only natural because wound healing starts with the formation of a blood clot; the degranulation of platelets and the release of platelet growth factors regulate the wound healing process. The mechanisms of tissue repair that are aided by platelet-derived growth factors include cell migration and proliferation, the formation of new blood vessels from existing ones, extracellular matrix formation, and the remodeling of cells (Fig 2-1).

Over the last 30 years, the clinical use of PRP through various preparations and for a variety of therapies has grown in importance due mainly to the platelet growth factors released by PRP. These growth factor proteins exert tremendous influence on blood coagulation/clotting, immunities, angiogenesis, and wound healing. The concentration of platelets through cell sequestration to levels over 300 times their normal strength (with resultant concentrations in growth factors) allows clinicians to apply the concentrates to a number of wound healing therapies, including skin ulcers, oral and maxillofacial surgery and implantology, orthopedic surgery, burn treatment and the treatment of other wounds difficult to heal, soft tissue disease and injuries, and tissue engineering.6

This chapter focuses on the clinical application of PRP in the historically significant and wide-reaching medical areas of cardiothoracic surgery and orthopedics, respectively, as well as a number of miscellaneous clinical applications, including bone surgery, chronic wound healing, general surgery, neurosurgery, ophthalmology, otolaryngology, podiatry, and urology.

Cardiothoracic Surgery

Since the late 1980s, cardiac physicians have used cell-saving machines and platelet-rich plasmapheresis (allogeneic red blood cells and platelet concentrates) as methods to control nonsurgical bleeding after cardiopulmonary bypass (CPB) as well as postsurgical platelet dysfunction. Autologous blood components—including PRP, platelet-poor plasma (PPP), and red blood cell concentrate—are produced presurgically for postsurgical infusion to combat platelet dysfunction and bleeding.7 PRP has been used in cardiovascular surgery to maintain hemodynamic stability in patients following CPB.

FIG 2-1 Wound healing mechanisms of tissue repair that are enhanced by the application of PRP.

Box 2-1 Effects of platelet-rich plasmapheresis and PRP transfusion on cardiopulmonary bypass surgery outcomes8

• Reduces postoperative blood loss

• Reduces postoperative fresh frozen plasma transfusion

• Reduces postoperative red blood cell transfusion

• Reduces postoperative allogeneic red blood cell transfusion

A 2019 meta-analysis of randomized controlled clinical trials (RCTs) concluded that conducting platelet-rich plasmapheresis before CPB and transfusing PRP after reversal of heparin could reduce postoperative blood loss and hence the need for blood transfusions (Box 2-1).8 The study examined 15 RCTs with a total of 1,002 patients. Half of the patients (501) received PRP and the other half served as controls. PRP reduced the total volume of postoperative blood loss, reduced postoperative fresh frozen plasma transfusion, reduced postoperative red blood cell transfusion, and reduced the proportion of patients requiring postoperative allogeneic red blood cell transfusion. However, a high degree of undetermined heterogeneity among the analyzed trials suggests that more precise RCTs are needed to confirm these conclusions.

PRP in the form of platelet gel has been used to help control bleeding and to prevent infection on CPB wound tissue of the sternum via syringe or spray-tip catheter application prior to closure (Fig 2-2). Platelet gel has also been injected into a patient’s leg vein harvest site. Efforts to predict preoperatively the effectiveness of platelet infusion postsurgery are ongoing, including calibrated automated thrombography assays for estimations of blood loss.9 PRP has also been combined successfully with antioxidant and anti-inflammatory agents in an intramyocardial hydrogel injection to treat injured heart muscles after an acute myocardial infarction in a randomized study that used a pig model.10

Postoperative wound dehiscence and infection are a common and extremely serious complication of cardiac surgery, affecting up to 8% of patients undergoing median sternotomy. They are associated with long-term antibiotic use, prolonged hospital stays, multiple operative procedures, and high costs. Over a 7-year period, 2,000 patients undergoing open cardiac operations requiring sternotomy were enrolled in a study evaluating the use of PRP to minimize the incidence of deep sternal wound infections (DSWI).11 Half of the patients (1,000) received standard of care treatment for sternal closure, and the other half received standard of care plus the application of PRP to the sternum at the time of closure. The outcome analysis showed that in the PRP group the incidence of DSWI decreased from 2.0% to 0.6%, sternal wound infections decreased from 8.0% to 2.0%, and the rate of readmission decreased from 4.0% to 0.8%. Moreover, PRP reduced the total costs associated with deep and superficial wound complications from $1.25 million to $593,000. Although this was not an RCT, the study nevertheless demonstrated the value of PRP for cardiac surgery patients and the health care system given its large sample size.

FIG 2-2 Application of PRP gel with a spray-tip catheter to prevent infection in the sternum wound prior to closure in CPB surgery.

FIG 2-3 Injection of PRP into the subacromial space of the shoulder decreases the rate of retears in patients with rotator cuff injuries.

Sports Medicine

Rotator cuff injury (Fig 2-3) is a common musculoskeletal condition involving torn tendons and muscles. Pain and shoulder immobility can severely impact a person’s quality of life and usually requires arthroscopic surgery. A systematic review and meta-analysis of RCTs was performed in 2019 to investigate whether application of PRP during arthroscopic repair of rotator cuff tears decreases retear rates and improves clinical outcomes. A total of 880 patients were enrolled across 13 RCTs, including 439 in the PRP groups and 441 in the control groups (ie, no PRP during surgery), and the final follow-up was 6 to 16 months posttreatment. Of the 13 studies, 12 reported the rate of retear at the final follow-up. The pooled data showed that retears occurred in 63 of 392 patients (16%) in the PRP group and 90 of 381 patients (24%) in the control group. The authors concluded that PRP had a significantly positive effect on postoperative retear rates and on functional outcome measures, including constant shoulder scores, constant pain scores, UCLA shoulder scores, and visual analog scale (VAS) pain scores (Box 2-2).12

Box 2-2 Effects of application of PRP on retear rates following rotator cuff repair surgery12

• Positive effect on retear rates

• Reduced/improved constant pain scores

Pain relief and improved function in humans, along with improved cartilage repair in animals, are the focus of a 2013 sports medicine article, whose authors note the effect of PRP on stem cells and chondrocytes, as well as PRP’s ability to improve cartilage regeneration, particularly in cases of osteoarthritis.13 A 2015 study lists PRP therapy along with steroid injections and anesthetics as current treatment for skeletal muscle injuries, which are among the most common sports injuries, resulting in reduction of practice and play for athletes. The authors note that future therapies could include transforming growth factor ß (TGF-ß) and angiotensin II as well as muscle-derived stem cells and that effective treatment is predicated on accurate diagnoses of these injuries, including...