INTRODUCTION
As with most endeavors in life, the healing arts are divided into both the theoretical and the practical spheres. Surgeons are fortunate to practice equally in both spheres by applying their intellect and technical skill to the diagnosis and treatment of sickness. The practice of surgery is unique in the realm of medicine and correspondingly carries added responsibilities. Patients literally place their trust in the hands of surgeons. The profound nature of cutting into another human being, and artfully manipulating his or her physical being to achieve wellness, requires reverence, skill, and judgment.
Technologic advances in modern medicine have led to the rise and establishment of procedure-related specialties, including invasive cardiology and radiology, dermatology, intensive care medicine, and emergency medicine, to name a few. Manipulative skills are now required not only in the operating room but also in procedure rooms and emergency rooms for invasive treatments and repairing traumatic injuries. Therefore, medical students and residents should master the basics of surgical technique so they are well prepared for the challenges ahead.
PREOPERATIVE ISSUES
For well-trained and experienced surgeons, performing an operation is usually a routine affair and is relatively simple. One of the difficulties in taking care of surgical patients, however, is actually making the decision to operate. Operating is simple; deciding not to operate is the more difficult decision. Ultimately, the surgeon and patient must assess the risk-to-benefit ratio and decide whether the potential benefits of surgery outweigh the potential risks. Once the decision has been made to proceed with surgery, the surgeon must formulate a clear operative plan, taking into account and preparing for any potential deviations that may be required based on the intraoperative findings.
The relationship between patient and doctor is based on a special trust. In the surgical sphere, individuals grant their surgeon permission to render them unconscious, invade their body cavities, and remove or manipulate their internal structures to a degree that the latter deems appropriate. Physicians must never minimize the importance of this special trust that underlies the surgical relationship. A surgeon gains a patient's trust by engaging in a thorough discussion before the decision to operate is reached, outlining the clinical situation and indications for surgery. All reasonable management options should be reviewed and the risks and potential complications of each presented. This process of decision making is known as informed consent. Appropriate written documentation must be obtained—usually a "request" for operation, rather than a more passive "consent"—and signed by the patient or guardian, the person performing the procedure, and a witness.
Adequate preparation of a patient for surgery depends on examining the magnitude and nature of the intended operation in light of the patient's general medical condition. The surgical patient must be able to endure the potential insults of surgery (hypotension, hypoxemia, hypothermia, anemia, and postoperative pain) without being exposed to unacceptable risks of morbidity and mortality. All patients, particularly older adult patients with multiple medical problems, should undergo an appropriate preoperative evaluation to identify and thoroughly evaluate medical illnesses and thereby more accurately establish the degree of
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perioperative risk that the proposed surgery entails. The two main goals of preoperative evaluation are to assess and maximize the patient's health, as well as to anticipate and avoid possible perioperative complications. Consultation with a cardiologist, pulmonologist, endocrinologist, or internist may involve specific diagnostic tests and laboratory studies (Table 1-1).
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TABLE 1-1 Preoperative Diagnostic Testing |
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Preoperative assessment is also made by an anesthesiologist before surgery to determine the patient's fitness for anesthesia, which is evaluated according to the American Society of Anesthesiologists Physical Status Classification System. Class I indicates a fit and healthy patient, whereas class V indicates a moribund patient not expected to survive 24 hours with or without an operation (Table 1-2).
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TABLE 1-2 American Society of Anesthesiologists Physical Status Classification System |
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Routine preoperative screening tests are ordered only when indicated by rational guidelines. Gone are the days when asymptomatic, low-risk, minor surgery patients were subjected to an extensive and expensive battery of tests (blood tests, chest x-ray, urinalysis, and electrocardiogram). The belief was that a thorough array of tests would systematically detect occult conditions, thereby avoiding potential morbidity and mortality. Over time, such an approach has been devalued, as published studies have shown that routine medical testing has not measurably increased
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surgical safety. Therefore, modern preoperative testing relies on defined guidelines that focus on evaluating the risk arising from patient-specific comorbidities and conditions.
A foundational principle of the medical tradition is to do no harm: primum non nocere. In 2000, a widely publicized report from the Institute of Medicine, To Err is Human, estimated that 98,000 people die each year in U.S. hospitals as a result of medical injuries. This report, among others already in the literature, led to the creation of a number of national quality improvement projects that were specifically designed to improve surgical care in hospitals. One of the best known is the Surgical Care Improvement Project (SCIP), part of a national campaign aimed at reducing surgical complications by 25% by 2010. The multiyear project is sponsored by the Centers for Medicare and Medicaid Services in partnership with the U.S. Centers for Disease Control and Prevention (CDC), the Joint Commission, Institute for Healthcare Improvement, and the American Hospital Association. With a goal of saving lives and reducing patient injuries, SCIP examines the process and outcome measures related to infectious, cardiac, venous thromboembolic, and respiratory care. As hospitals incorporate these measures into their provision of care, it is expected that the rates of postoperative wound infection, perioperative myocardial infarction, deep venous thrombosis and pulmonary embolism, and ventilator-related pneumonia will decrease (Table 1-3).
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TABLE 1-3 SCIP Measures |
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Regarding antibiotic prophylaxis for the prevention of surgical site infections, broad implementation of the measures outlined by SCIP could decrease the overall incidence significantly. In essence, selecting the appropriate antibiotic, administering it within 60 minutes of incision, and discontinuing it within 24 hours postoperatively is the goal.
Regarding preoperative hair removal, minimal or no hair removal is preferred. The CDC guidelines for hair removal state that only the interfering hair around the incision site should be removed, if necessary. Removal should be done immediately before the operation, preferably with electric clippers. Using electric clippers minimizes microscopic skin cuts, which are more common from traditional blade razors and serve as foci for bacterial multiplication.
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Maintaining patient core body temperature to avoid hypothermia should be standard practice. Both passive and active warming measures should be used when indicated (e.g., blankets, fluid warmer, forced-air warmer).
Traditional practice for colon surgery has included preoperative mechanical and chemical cleansing of the large intestine in an attempt to decrease intraluminal bacterial counts and thereby minimize anastomotic leakage and postoperative infectious complications. This established practice is based on observational studies and animal experiments and is not supported by prospective randomized trial data. Interestingly, recent prospective randomized trials call the routine use of mechanical bowel preparation into question, and a Cochrane Review (2005) concludes, "Mechanical bowel preparation before colorectal surgery cannot be recommended as routine." Given the present data, mechanical bowel preparation should be used selectively depending on the clinical situation.
Regarding active infections at the time of elective surgery, CDC guidelines advise diagnosis and treatment of "all infections remote to the surgical site before elective operation and postpone elective operations on patients with remote site infections until the infection has resolved."
The publication of the Institute of Medicine report in 2000 brought into focus, and set as a national priority, an issue that had been steadily growing since the mid-1990s: improving medical and surgical safety. Before the report, large medical organizations had begun to apply a systems approach to examining medical errors. Pioneering efforts by the Veterans Health Administration to decrease medical errors led to the establishment of the National Surgical Quality Improvement Program in 1994. The core concept of such programs is to create systems of safety similar to the aviation and nuclear power industries. Highly visible aviation accidents have been found to involve human error 70% of the time, as shown by National Aeronautics and Space Administration research. This statistic parallels the less visible medical experience, as analysis of Joint Commission data on sentinel events shows that communication failures were the primary root cause in more than 70% of events. Additional oft-cited studies indicate that surgical errors result from communication failure, fatigue, and lack of surgical proficiency. In an effort to inculcate a culture of safety and minimize surgical misadventure through miscommunication, many hospitals have instituted Highly Reliable Surgical Team (HRST) training. This training is modeled on Crew Resources Management training from the aviation industry, which has been shown to enhance error reduction. Some of the HRST training goals are creating an open and free communication environment, minimizing disruptions to patient care, improving coordination among departments, and conducting quality preoperative briefings and verifications.
INTRAOPERATIVE ISSUES
After completing the HRST preoperative briefing communication with the anesthesiologist and operating room team, ensure that the overall operating room environment is to your satisfaction. The operating table and overhead lights should be correctly positioned. Room temperature and ambient noise should be adjusted as necessary. Play music if appropriate. Ensure adequate positioning and prepping of the patient. Communicate again with the team to confirm readiness. Then scrub, gown, and drape. Before incision, again to minimize surgical errors, many hospitals call for a final check or "time out" to ensure that the correct patient is undergoing the correct procedure.
Deciding where to make the skin incision is usually straightforward. Thought should be taken to consider possible need for extending the incision or possibly converting from a laparoscopic approach to open surgery. Before incising the skin, consider the skin's intrinsic tension lines to maximize wound healing and cosmesis of the healed scar. Incisions made parallel to the natural lines of tension usually heal with thinner scars because the static and dynamic forces on the wound are minimized. When making elective facial skin excisions or repairs of traumatic facial lacerations, keep in mind that incisions perpendicular to these tension lines will result in wider, less cosmetically acceptable scars (Fig. 1-1).
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Figure 1-1 • Skin tension lines of the face and body. Adapted from Simon R, Brenner B. Procedures and Techniques in Emergency Medicine. Baltimore, MD: Williams & Wilkins; 1982. |
Although general anesthetic techniques are usually the anesthesiologist's job, all invasive practitioners should have a working knowledge of local anesthetics. Depending on the procedure being performed, the choice of local anesthetic must be tailored to each patient. Local anesthetics diffuse across nerve membranes and interfere with neural depolarization and transmission. Each local anesthetic agent has a different onset of action, duration of activity, and toxicity. Epinephrine is often administered concurrently with the local anesthetic agent to induce vasoconstriction, thereby prolonging the duration of action and decreasing bleeding. The two most commonly used local anesthetics are the shorter-acting lidocaine (Xylocaine) and
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the longer-acting bupivacaine (Marcaine), the properties of which are outlined in Table 1-4.
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TABLE 1-4 Pharmacologic Properties of Local Anesthetic Agents |
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Lidocaine (1% and 2%, with and without epinephrine) has a rapid onset of action, achieving sensory block in 4 to 10 minutes. The duration of action is approximately 75 minutes (range, 60 to 120 minutes). The maximum allowable dosage is 4.5 mg/kg per dose without epinephrine or 7 mg/kg per dose with epinephrine.
Bupivacaine (0.25%, 0.5%, and 0.75%, with and without epinephrine) has a slower onset of action, taking 8 to 12 minutes for a simple block. Duration of action is approximately four times longer than that of lidocaine, lasting 2 to 8 hours, making bupivacaine the preferred agent for longer procedures and for prolonged action. The maximum allowable dosage is 3 mg/kg per dose.
INSTRUMENTS
The basic tools of a surgeon are a knife for cutting and a needle with suture for restoring tissues to their appropriate position and function. Additional tools and instrumentation simply allow operations to be performed with greater finesse.
The most commonly used knife blades are illustrated in Figure 1-2 and are made functional by attachment to a standard no. 3 Bard-Parker knife handle. Choose the size and shape of the blade based on the intended indication. Abdominal or thoracic skin incisions are typically made with no. 10, 20, or 22 blades, whereas more delicate incisions could require the smaller no. 15 blade. The sharp-tipped no. 11 blade is ideal for entering and draining an abscess or for making an arteriotomy by incising a blood vessel in preparation for vascular procedures.
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Figure 1-2 • General surgery knife blades. Shown here are Bard-Parker knife blades nos. 10, 11, 15, 20, and 22. |
Scissors are mainly used for dissecting and cutting tissues. All scissors are designed for right-handed use. Each pair of scissors should only be used for the indication for which it was designed (Fig. 1-3). Most scissors have either straight or curved tips. Fine iris scissors are used for delicate dissection and cutting. Metzenbaum scissors are versatile, general-use instruments. Sturdy Mayo scissors are used for cutting thick or dense tissues, such as fascia, scar, or tendons.
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Figure 1-3 • Mayo, Metzenbaum, and iris scissors. |
Various forceps have been developed to facilitate manipulation of objects within the operative field, as well as to stabilize tissues and assist in dissection. All forceps perform essentially the same function but differ in the design of their tips and their intrinsic delicacy of form (Fig. 1-4). Toothed forceps are useful for stabilizing and moving tissues, whereas smooth atraumatic forceps are more appropriate for delicate vascular manipulation. DeBakey forceps are good general-use instruments with
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atraumatic flat tips and tiny fine serrations. Fine-toothed Adson forceps are ideal for skin closure, and stout-toothed Bonney forceps are excellent for facial closure.
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Figure 1-4 • Smooth, Adson, and toothed forceps. |
Needle and suture are used to maintain tissue apposition until healing has occurred. The array of needles and suture material is vast; therefore, the surgeon's choice is based on the specific indication at hand.
Needles come either straight or curved. Curved needles are usually half circle or three-eighths circle. Sewing in a deep hole may require a five-eighths circle needle, whereas microsurgery often requires quarter circle needles.
Needles can have an eye for threading the suture (French eye) or an already attached suture (swaged). Most needles today are swaged, meaning they are a needle-suture combination. Etymologically, a swage is a blacksmithing tool used to shape metal. Thus a swaged needle is manufactured by placing the suture into the hollow shank of a needle and then compressing the needle around the suture, holding it firm. Some sutures are swaged to needles in such a manner that they pop off if excess tension is applied between suture and needle.
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Needle tips are either tapered or cutting. Tapered needles are circumferentially smooth and slide between the elements of tissues, whereas cutting needles are triangular in cross section and cut through tissues like a tiny knife (Fig. 1-5).
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Figure 1-5 • Needle characteristics. |
Suture material is categorized according to its permanence (absorbable or nonabsorbable), its structure (braided or monofilament), and its caliber (Table 1-5). Absorbable suture material is made from either naturally derived, collagen-based materials or synthetic polymers. Examples of absorbable suture material are gut (plain and chromic), polyglactic acid (Vicryl), polyglycolic acid (Dexon), polyglyconate (Maxon), and polydioxanone (PDS). The suture is either hydrolyzed by water or undergoes enzymatic digestion, thereby losing tensile strength over time.
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TABLE 1-5 Common Suture Material |
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Permanent nonabsorbable sutures are made from materials impervious to significant chemical degradation and are useful for maintaining long-term tissue apposition. Examples of permanent nonabsorbable suture material are nylon, polypropylene, stainless steel, and silk.
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CLOSURE TECHNIQUES
There are many techniques for closing wounds (Fig. 1-6). Wounds can be closed using a continuous stitch that is quick to perform and results in tension distributed along the length of the suture. Simple interrupted stitching allows for precise tissue approximation (skin or fascia). Mattress stitches can be placed either vertically or horizontally, allowing excellent skin apposition and eversion while minimizing tension. Subcuticular stitching using an absorbable suture at the dermal-epidermal junction is a convenient skin-closure technique, allowing epidermal apposition so that postoperative suture removal is unnecessary. Regardless of the closure technique used, certain basic principles must be considered to avoid wound breakdown and to achieve a well-healed, cosmetically satisfactory scar:
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Figure 1-6 • Suturing techniques: (A) Continuous, (B) simple interrupted, (C) horizontal mattress, (D) vertical mattress, and (E) subcuticular. (From Taylor JA. Blueprints Plastic Surgery. Malden, MA: Blackwell Publishing; 2005:7.) |
An alternative to sutured skin closure of wounds is skin apposition using metal staples. Many elective surgical wounds are closed with skin staples, because the technique allows for rapid skin closure, minimal wound inflammatory response, and near-equivalent cosmetic results. This technique usually works best with two operators: one to evert and align the skin edges with forceps and another to fire the stapler (Fig. 1-7).
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Figure 1-7 • Wound closure using metal staples. |
Removal of staples is performed using a simple handheld device that deforms the staple and reconfigures the staple shape, allowing for smooth, easy withdrawal (Fig. 1-8).
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Figure 1-8 • Technique for staple removal. |