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over sedation is to administer excessive amounts of fentanyl, instead of maximizing the use of the local anesthetic. Towards the end of the procedure, there is nothing wrong with cutting back on the amount of sedation, and allowing the patient to become more awake. In addition, excessive administration of versed can result in the opposite effect: an overly anxious, and occasionally claustrophobic patient. When this occurs, it is best to withhold sedation, reassure the patient and allow her to reorient herself.
Suggested Reading
1.American Society of Anesthesiologists task force on sedation and analgesia by nonanesthesiologists. Practice guidelines for sedation and analgesia by nonanesthesiologists. Anesthesiology 1996; 84:459.
2.Byun MY, Fine NA, Lee JY et al. The clinical outcome of abdominoplasty peformed
9under conscious sedation: Increased use of fentanyl correlated with longer stay in outpatient unit. Plast Reconstr Surg 1999; 103:1260.
3.Dionne RA, Yagiela JA, Moore PA et al. Comparing efficacy and safety of four intravenous sedation regimens in dental outpatients. J Am Dent Assoc 2001; 132:740.
4.Iverson RE. Sedation and analgesia in ambulatory settings. American society of plastic and reconstructive surgeons. Task force on sedation and analgesia in ambulatory settings. Plast Reconstr Surg 1999; 104:1559.
5.Finder RL, Moore PA. Benzodiazepines for intravenous conscious sedation: Agonists and antagonists. Compendium 1993; 14:972.
6.Kallar S. Conscious sedation in ambulatory surgery. Anesth Rev 1991; 18:9.
7.Klein JA. Tumescent technique for regional anesthesia permits lidocaine doses of 35 mg/kg for liposuction. J Dermatol Surg Oncol 1990; 16(3):248.
8.Marcus JR, Few JW, Chao JD et al. The prevention of emesis in plastic surgery: A randomized, prospective study. Plast Reconst Surg 2002; 109:2487.
9.Marcus JR, Tyrone JW, Few JW et al. Optimization of conscious sedation in plastic surgery. Plast Reconst Surg 1999; 104:1338.
Chapter 10
Principles of Reconstructive Surgery
Constance M. Chen and Robert J. Allen
Introduction
Plastic and reconstructive surgery is a field that relies upon basic principles to restore form and function to the human body. Whether it is a gunshot wound to the face, a congenital hand deformity, or a malformed breast, plastic surgeons must be adept at adapting a fundamental knowledge of human anatomy and physiology to create ingenious solutions to ever-changing challenges. Unlike techniques which must be modified with each new advance in medical technology, the use of principles makes it possible for the plastic surgeon to address problems as varied as the infinite diversity of the human species. Rote memorization of operative steps and mathematical formulas are insufficient. The reconstruction of the human body depends upon the ability to devise creative solutions based on core principles. Over the years, numerous efforts have been made to categorize these principles. Despite changes in technique, the fundamental principles of plastic and reconstructive surgery have withstood the test of time.
Ambrose Paré
The earliest principles of reconstructive surgery may be attributed to the French surgeon, Ambrose Paré, who in 1564 published five basic principles of plastic surgery. The first principle was “to take away what is superfluous.” Whether applied to the excision of redundant tissue or the complete amputation of a surplus structure such as a digit or a supernumerary nipple, this first principle emphasized the need to eliminate that which served no purpose. The second principle was “to restore to their places things which are displaced.” Whether applied to a congenital deformity, such as a cleft lip, or an acquired deformity, as in trauma, this principle required recognition of normal parts and diagnosis of the abnormal position. Likewise, the third and fourth principles, “to separate tissues which are joined together,” and “to join those tissues which are separate,” also required the ability to conceptualize a hypothetical norm. Indeed, a given defect could often be determined accurately only after distorted tissue was returned to its normal shape. This was true whether applied to a congenital defect, such as syndactyly, or an acquired defect, such as a burn contracture. Finally, the fifth principle, “to supply the defects of nature,” also required the ability to visualize restoration to a normal state.
Modern Plastic Surgery: Gillies and Millard
Building upon these early ideas, Sir Harold Gillies and D. Ralph Millard took the principles of Paré to the next level. Recognizing that the remodeling of human tissue was different from clay, Gillies and Millard took as their founding principle
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Table 10.1. Gillies’ ten commandments of plastic surgery
1.Thou shalt make a plan.
2.Thou shalt have a style.
3.Honor that which is normal and return it to normal position.
4.Thou shalt not throw away a living thing.
5.Thou shalt not bear false witness against thy defect.
6.Thou shalt treat thy primary defect before worrying about the secondary one.
7.Thou shalt provide thyself with a lifeboat.
8.Thou shalt not do today what thou canst put off until tomorrow.
9.Thou shalt not have a routine.
10.Thou shalt not covet thy neighbor’s plastic unit, handmaidens, forehead
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that “plastic surgery is a constant battle between blood supply and beauty.” That is to say, the reshaping of human structures demanded that its vitality as living tissue be respected. Drawing upon the wisdom of his mentor, Sir Harold Gillies, Millard produced one of the most widely recognized efforts to outline the principles of reconstructive surgery. In 1950, Millard codified rules learned from Gillies and published them as the “ten commandments” of plastic surgery (Table 10.1). Shortly thereafter, the pair expanded these ideas to 16 principles that would apply not only to plastic surgery problems but also to a philosophy of life in general. Millard went on to develop the concept of principles still further in his classic tome, Principalization of Plastic Surgery. Divided into four broad sections, this work offered 33 commonsense rules to help plastic surgeons fashion answers to a variety of surgical problems.
Preparational Principles
Millard’s first 12 principles fell under the framework of “Preparational Principles”-that is, principles to keep in mind before making the opening incision. The first principle was to “correct the order of priorities.” Applied broadly, this could mean emphasizing integrity and ethics; it could mean prioritizing function over form; and it could also mean performing a blepharoplasty before a facelift since the latter could affect the former but not vice versa. The bottom line was that whether in life or in a specific procedure, each part needed to be considered in the context of the whole.
The second principle was that “aptitude should determine specialization,” meaning that the plastic surgeon should play to strengths when deciding whether to focus on reconstructive surgery, cosmetic surgery, microvascular surgery, craniofacial surgery, head and neck oncology, hand surgery, burn physiology or laboratory research. Millard emphasized that a person who initially appeared inept in one area could later progress to excel above all others in the same area. Using himself as an example, Millard revealed that he took an aptitude test early in his career that determined that he would be well-suited to writing and possibly medicine, but completely unsuited for surgery due to a perceived inability to visualize objects in three dimensions. Despite this, he went on to become one of the most accomplished plastic surgeons in history, known especially for the three-dimensional rotation-advancement flap that is the standard of care for cleft lip repair today.
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The third principle was to “mobilize auxiliary capabilities.” That is to say, the plastic surgeon should incorporate individual talents to develop a “personal style with individual flair.” Advised to develop one primary capability and several secondary talents such as sculpture, music, writing or painting, the ideal plastic surgeon would be multi-talented for maximal depth and versatility in the operating room. The fourth principle was to “acknowledge your limitations so as to do no harm,” a self-evident principle that spoke to the temptation to persevere on a case with endless complications. Instead, the successful surgeon should know when to stop. The flip side of this was the fifth principle, which was to “extend your abilities to do the most good.” This spoke to the moral obligation to use plastic surgical training to alleviate human suffering, that is, to reconstruct mutilated or severely deformed patients instead of limiting one’s practice to purely aesthetic procedures. The sixth principle was to “seek insight into the patient’s true desires.” Delving into the psyche, this
principle directed the plastic surgeon to decipher a patient’s actual problems instead 10 of merely taking the stated problem at face value to preempt patient disappointment, improve public relations and prevent postoperative legal complications.
The seventh principle was to “have a goal and a dream.” In plastic surgery, this principle shifted depending on whether a procedure was primarily cosmetic, in which the goal would be to surpass normal, or primarily reconstructive, in which the goal would be to attain normal. Either way, the plastic surgeon should have a target in mind before beginning an operation. The eighth principle was to “know the ideal beautiful normal.” While this ideal beautiful normal could vary among different ethnic backgrounds, it was important for the plastic surgeon to be able to define it in order to attain pleasing aesthetic proportions and visual harmony.
The ninth principle was to “be familiar with the literature.” Knowing what had already been described assisted a surgeon in discriminating between procedures that would and would not be successful; it also gave the surgeon access to a collective bank of experience that allowed extension beyond what one person could accrue in a lifetime. The tenth principle, to “keep an accurate record,” was like the sixth principle in that its underlying purpose was both to further patient care and provide legal protection for the surgeon. In addition, since memory was inherently unreliable, accurate written and photographic records provided baseline references that allowed the plastic surgeon to coordinate multi-staged procedures to achieve a successful final result.
The eleventh principle was to “attend to physical condition and comfort of position.” Often overlooked by single-minded surgeons, the basis of this principle was the belief that the optimal surgical performance depended upon good physical condition and a comfortable working position for the surgeon. Finally, the twelfth principle, “do not underestimate the enemy,” acknowledged that peril lay behind every procedure. Thus, whether the enemy was hypertrophic scar formation or inadequate vascular supply, it was never possible to be overly vigilant in preventing surgical complications.
Executional Principles
The second category of principles addressed the wielding of the blade. The thirteenth principle, “diagnose before treating,” emphasized that observation was the basis of surgical diagnosis. The plastic surgeon must use all senses—particularly visual and tactile cues—to accurately determine a problem before proceeding with an operation. The fourteenth principle was reminiscent of Paré, in that it advised
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the plastic surgeon to “return what is normal to normal position and retain it there.” As previously mentioned, displacement of structures could be due to failure in normal embryonic development or as a direct result of trauma, ablation, scar contraction, or even the aging process, but correction required the ability to recognize the norm in order to restore displaced parts to their correct place.
The fifteenth principle stated that “tissue losses should be replaced in kind.” More specifically, when attempting reconstruction of lost body parts, bone should be replaced with bone, muscle with muscle and glabrous skin with glabrous skin. If exact replacement was impossible, then a similar substitute should be made, such as a beard with scalp, thin skin for an eyelid, thick skin for the sole of a foot, and a prosthesis for an eye. The idea was that replacing like with like would give the most natural outcome. The sixteenth principle advised the plastic surgeon to “reconstruct by units.” By basing reconstruction on unit borders demarcated by creases, margins,
10angles and hairlines, surgical scars could often be concealed by the meeting of light and shadow.
The seventeenth principle was to “make a plan, a pattern and a second plan (lifeboat).” By visualizing an entire operation from beginning to end, the plastic surgeon could anticipate possible difficulties and then proceed to devise a secondary plan for use should the primary plan fail. The eighteenth principle was to “invoke a Scot’s economy.” This involved thrift in surgery, in which no tissue was ever discarded until it was certain that it was no longer needed. A corollary of this was to discard the useless, as once a piece of tissue was determined to have no further value it should be removed—but refrigerated storage was advised even then in case the tissue could be used later.
The nineteenth principle was to “use Robin Hood’s tissue apportionment.” That is, Robin Hood would steal from the rich to give to the poor. Likewise, this principle advised using excess tissue to make up for areas with tissue deficits by rotating, transposing, or transplanting expendable tissue flaps to areas in need. The corollary to this was the twentieth principle, to “consider the secondary donor site.” That is, while reconstructing deficient areas with tissue taken from areas that were more ample, the resulting secondary defect must also be considered to make sure that its sacrifice was not too deforming. The twenty-first principle was to “learn to control tension.” In opening, tension usually facilitated a clean cut with the scalpel; in closure, tension could lead to tissue necrosis or excess scarring; in flap design, skin tension lines could be identified and used to camouflage scars. The twenty-second principle was to “perfect your craftsmanship.” For the plastic surgeon, “good” suggested mediocrity, and nothing short of perfection was acceptable. The twenty-third and final executional principle was “when in doubt, don’t!” Doubt should function as a deterrent, and if a solution to a problem left seeds of doubt, it was better to develop a better idea.
Innovational Principles
The third category of principles governed the generation of new concepts in plastic surgery. The twenty-fourth principle was to “follow up with a critical eye.” That is, it was important to follow patients postoperatively over time to critically evaluate results, as regular review of one’s handiwork was the best way to spur advancement and improvement of surgical procedures. Likewise, the twenty-fifth principle, to “avoid the rut of routine,” exhorted surgeons to shun mindless and tenacious clinging to unthinking rituals. Again, by thinking outside the box, the plastic surgeon could make the advance to the next level of innovation and development. The
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twenty-sixth principle, “imagination sparks innovation,” was the “breakthrough” or |
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problem-solving principle that encouraged free-spirited thinking and creativity. |
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The twenty-seventh principle, “think while down and turn a setback into a vic- |
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tory,” was labeled the “prince of principles” by Millard. It admonished the surgeon |
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not to panic or despair, or compound error when faced with possible defeat. In- |
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stead, the surgeon should keep cool while determining the cause of loss, expend no |
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energy in worrying about a compromised position, and make certain not to repeat |
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the same mistake while thinking one’s way to recovery. Finally, the twenty-eighth |
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principle was to “research basic truths by laboratory experimentation.” By testing |
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even minor theories in the laboratory, the surgeon could discover answers to plastic |
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surgical questions in a controlled setting. |
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Contributional Principles |
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The fourth set of principles governed ways to contribute to the field of plastic |
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surgery. The twenty-ninth principle was to “gain access to other specialties’ problems.” |
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By consulting with physicians or surgeons from other specialties, it could be possible |
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to learn management of common complications that would both benefit patients as |
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well as broaden the base of plastic surgery. The thirtieth principle was that “teaching |
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our specialty is its best legacy.” The implication was that the best way to extend plastic |
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surgery was to transmit knowledge via lectures, books, symposiums and personal ex- |
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periences to ensuing generations. The thirty-first principle was to “participate in re- |
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constructive missions.” Moreover, the ideal method to conduct such missions was to |
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lend specialists not just to operate, but to teach people in underdeveloped countries |
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how to perform the operations and manage all the postoperative care themselves. |
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Inspirational Principles |
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The final set of principles attempted to prod the plastic surgeon to strive for |
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perfection. Toward this end, the thirty-second principle was to “go for broke!” That |
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is, the plastic surgeon should use every means possible to overcome obstacles, strive |
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for the very best, and seek perfection. The thirty-third and last principle was to |
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“think principles until they become instinctively automatic in your modus oper- |
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andi.” By incorporating principles constantly and consistently into plastic surgical |
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practice, it would become second nature to avoid rote memorization of techniques |
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and instead stimulate the imagination to engage in innovative problem solving. |
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The Reconstructive Ladder |
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The traditional approach to the reconstruction of a variety of defects is based on |
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the concept of the reconstructive ladder (Fig. 10.1). The basic notion is that one |
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should use the simplest approach to solving a reconstructive problem, before ad- |
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vancing up the ladder to a more complex technique. Consequently, if the procedure |
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fails, one can climb to the next level of complexity. For example, a lower extremity |
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venous stasis ulcer should be treated by dressing changes alone or by a split-thickness |
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skin graft if these are applicable. A more complex reconstruction with a free flap |
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should be reserved as a last resort if all simpler options have been ruled out or have |
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failed. More recently, however, experienced reconstructive surgeons are beginning |
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to realize that certain problems are not amenable to simple solutions. In select cases, |
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bypassing the lower rungs of the reconstructive ladder and proceeding directly to |
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microvascular free tissue transfer is the optimal approach. A good example of this is |
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post-mastectomy breast reconstruction. For many surgeons, the free TRAM or DIEP |
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flaps have become the standard of care. |
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Figure 10.1. The reconstructive ladder.
Pearls and Pitfalls
Plastic surgery takes passion, determination and sacrifice. As plastic surgeons, we would like to create perfection. Yet techniques and procedures are always evolving, so the operative process must be based upon principles. Without a commitment to perfection, a concept of what beauty is, and what the end result will be ahead of time, the surgeon is lost. Poets can be our role models, because poets are creative and can help show us how to get going with the creative process. Ultimately, however, plastic surgery involves sacrifice, focus, determination and, above all, will power. When these qualities are combined, the plastic surgeon is able to elevate the work that is performed. A person who is able to go to work and create something close to perfection, striving for perfection, will lead a very satisfying life. By its very nature, then, plastic surgery gives us the opportunity to enjoy that ideal life.
Suggested Reading
1.Chase RA. Belabouring a principle, milestones in modern plastic surgery. Ann Plast Surg 1983; 11:255-60.
2.Gillies HD, Millard Jr DR. The Principles and art of plastic surgery. 1st ed. Boston: Little, Brown and Co., 1957.
3.Millard Jr DR. Plastic Peregrinations. Plast Reconstr Surg 1950; 5:26-53.
4.Millard Jr DR. Principlization of plastic surgery. 1st ed. Boston, Toronto: Little Brown and Co., 1986.
5.Rana RE, Puri VA, Baliarsing AS. Principles of plastic surgery revisited. Indian J Plast Surg 2004; 37:124-125.
Chapter 11
Principles of Surgical Flaps
Constance M. Chen and Babak J. Mehrara
Introduction
The underlying principle of all surgical flaps is the ability to maintain a viable blood supply upon transfer of flap tissue from a donor site to a recipient site. Given this fundamental capacity to retain vascular circulation, surgical flaps may be classified in many ways. One approach is by composition, as a flap may be made up of many different kinds of tissue. Another is by vascularity, and several different schemata have been developed to categorize flaps by the type of vascular supply. A third manner of categorizing flaps is by method of movement, and it is important to understand the basic techniques of flap transfer. Unlike a graft, which is wholly dependent upon the recipient bed to provide blood supply, a flap by definition is able to preserve its own vascular supply for survival. Thus, whether classifying a flap by composition, vascularity or method of movement, the core principle essential to all flaps is how to maintain blood supply so that the flap tissue will remain robust after transfer to its new site.
Composition
The most basic way to think about a flap is to consider what tissues are contained within it. A flap may contain skin, fascia, muscle, bone or various combinations of these tissues. As the underlying principle of any flap is its ability to retain its own blood supply, the amount of tissue that may be carried within it is dictated by the minimum or maximum amount of tissue that can be transferred with intact vascularity. When more than one type of tissue is contained within a flap, it is called a “composite flap.”
The simplest type of flap is the skin flap. The blood supply of the skin is contained largely in the dermal and subdermal plexus and derives from two main sources: a musculocutaneous vascular system and a direct cutaneous vascular system. When the blood supply to the skin is via a named artery, the skin flap is called an “axial flap.” When the blood supply to the skin lacks a significant pattern in its vascular design, the skin flap is called a “random flap.” Either way, the survival of a cutaneous flap depends on the number and type of blood vessels at the base of the flap. For an axial flap, the survival pattern of the flap is based on the length of the underlying feeding artery. For a random pattern flap, the length and width should be designed in a 2:1 ratio, as a wider base width increases the chance that a large vessel will be incorporated to provide an adequate blood supply to the enclosed dermal-subdermal plexus. Even in an axial flap, the distal borders of the flap are also random pattern with distal perfusion from the dermal-subdermal plexus (Fig. 11.1).
Skin flaps may also be transferred based on the vascular plexus of the deep fascia, in which case they are termed “fasciocutaneous flaps.” The blood supply of the deep fascia is derived from perforating vessels of regional arteries that pass along the fibrous septa of muscle bellies or muscle compartments. Including the deep fascia
Practical Plastic Surgery, edited by Zol B. Kryger and Mark Sisco. ©2007 Landes Bioscience.
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Figure 11.1. Survival pattern of skin flaps. X = subdermal plexus. The distal end of axial flaps (cutaneous and myocutaneous) also have a random pattern.
along with the skin avoids tedious dissection and may also preserve adjacent subfascial arteries. Among the advantages of fasciocutaneous flaps in reconstructive surgery are ease of elevation and transfer, decreased bulk, good reliability, and decreased functional morbidity at the donor site. Depending on the size of the skin paddle, however, the secondary defect at the donor site may require coverage with a split-thickness skin graft.
Progressing one layer deeper still, another common flap in reconstructive surgery is the “myocutaneous” or “musculocutaneous” flap, which combines muscle, skin, and the intervening fascia and subcutaneous tissue. Supplied by one or more dominant vascular pedicle within the muscle instead of a direct cutaneous arterial source, the essential feature of a myocutaneous flap is that the underlying muscle “carries” the blood supply for the overlying skin. Myocutaneous flaps have two key advantages. First, the increased bulk better allows it to fill dead space. Secondly, myocutaneous flaps are also more resistant to bacterial infection than fasciocutaneous flaps by a factor of 100. This makes them very reliable and useful, particularly when increased bulk is needed with a robust arterial supply to fill a defect that has been subjected to chronic infection. If a skin paddle is not needed, muscle can also be transferred alone, without the overlying fascial and cutaneous tissue.
A final type of tissue commonly incorporated into a flap is bone. When taken with the overlying skin, this is called an “osseocutaneous flap.” A dominant vascular pedicle with perforating branches supplies the skin and periosteum. Usually taken as a free flap, the bone is harvested with a cuff of muscle and/or skin to reconstruct a skeletal framework with soft tissue. The long bones of the extremities, such as the fibula, are often used as they provide more length for shaping according to the required need.
Type of Blood Supply
Once the composition has been determined, flaps can be further categorized according to their blood supply. As mentioned earlier, random flaps are based
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primarily on the cutaneous blood supply from the dermal-subdermal plexus. |
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Pedicled or axial flaps are based on anatomically mapped or named blood vessels. |
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Fasciocutaneous flaps have been classified into three categories based on their |
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vascular patterns. |
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Type A: Direct cutaneous pedicle |
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Type B: Septocutaneous pedicle |
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Type C: Musculocutaneous pedicle |
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Muscle flaps may be classified in two different ways. First, Mathes and Nahai |
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developed a system of muscle classification based on circulatory patterns. |
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Type I: Single pedicle (e.g., tensor fascia lata) |
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Type II: Dominant pedicle(s) with minor pedicle(s) (e.g., gracilis) |
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Type III: Dual dominant pedicles (e.g., gluteus maximus) |
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Type IV: Segmental pedicle(s) (e.g., sartorius) |
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Type V: Dominant pedicle, with secondary segmental pedicle(s) (e.g., latissi- |
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mus dorsi) |
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Second, Taylor developed a system of muscle classification based on mode of |
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innervation. |
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Type I: Single, unbranched nerve enters muscle (e.g., latissimus dorsi) |
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Type II: Single nerve, branches prior to entering muscle (e.g., vastus lateralis) |
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Type III: Multiple branches from the same nerve trunk (e.g., sartorius) |
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Type IV: Multiple branches from different nerve trunks (e.g., rectus abdominis) |
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Finally, the body can be further segregated anatomically into three-dimensional |
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vascular territories called “angiosomes.” The angiosome is a composite unit of skin |
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and underlying deep tissue that is supplied by a source artery. Each angiosome de- |
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fines an anatomic unit of tissue from skin to bone that may be safely transferred as a |
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composite flap. The angiosomes are interconnected by either true anastomotic ar- |
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teries, in which there is no change in caliber between the vessels of adjacent |
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angiosomes, or reduced-caliber, choke anastomotic vessels. The junctional zone be- |
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tween adjacent angiosomes usually occurs within the muscles of the deep tissues |
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rather than between them, so that most muscles span across two or more angiosomes. |
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Thus, when designing musculocutaneous flaps it is possible to capture the skin is- |
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land from one angiosome by using muscle supplied from the adjacent angiosome. |
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Flap delay is defined as the surgical interruption of a portion of the blood sup- |
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ply in a preliminary stage prior to tissue transfer. The purpose of delay is to augment |
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the surviving portion of the flap. There are two schools of thought regarding the |
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pathophysiology of the delay phenomenon. The first holds that delay conditions |
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tissue to ischemic conditions so that it is able to survive with less vascular inflow. |
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The second believes that delay actually increases vascularity by dilating reduced-caliber |
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choke anastomotic vessels and stimulating additional vascular ingrowth. |
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Another way to increase survival of a myocutaneous flap is by supercharging |
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the blood supply. This method involves augmenting arterial inflow by using micro- |
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surgical techniques to bring in an additional vascular pedicle. Classically described |
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for use in a pedicled TRAM flap, the supercharging technique may be performed in |
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one of two ways. First, in the pedicled TRAM flap, the contralateral deep inferior |
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epigastric vessels may be retained in a cuff of inferior rectus muscle in a planned |
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vascular augmentation to a single-pedicle flap. Alternatively, the inferior epigastric |
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vessels on the pedicled side may be used to save a flap during the immediate postop- |
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erative period in an emergency “supercharged” TRAM flap. |
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