Setting Inpatient surgery is performed in a hospital, and the person undergoing surgery stays at least one night in the hospital after the surgery.
Outpatient surgery occurs in a hospital outpatient department or freestanding ambulatory surgery center, and the person who had surgery is discharged the same working day. Office-based surgery occurs in a physician's office, and the person is discharged the same day. At a
hospital, modern surgery is often performed in an
operating theater using
surgical instruments, an
operating table, and other equipment. Among United States hospitalizations for non-maternal and non-neonatal conditions in 2012, more than one-fourth of stays and half of hospital costs involved stays that included operating room (OR) procedures. The environment and procedures used in surgery are governed by the principles of
aseptic technique: the strict separation of "sterile" (free of microorganisms) things from "unsterile" or "contaminated" things. All surgical instruments must be
sterilized, and an instrument must be replaced or re-sterilized if it becomes contaminated (i.e. handled in an unsterile manner, or allowed to touch an unsterile surface). Operating room staff must wear sterile attire (
scrubs, a scrub cap, a sterile surgical gown, sterile latex or non-latex polymer gloves and a surgical mask), and they must scrub hands and arms with an approved disinfectant agent before each procedure.
Preoperative care Prior to surgery, the person is given a
medical examination, receives certain pre-operative tests, and their
physical status is rated according to the
ASA physical status classification system. If these results are satisfactory, the person requiring surgery signs a consent form and is given a surgical clearance. If the procedure is expected to result in significant blood loss, an
autologous blood donation may be made some weeks prior to surgery. If the surgery involves the
digestive system, the person requiring surgery may be instructed to perform a
bowel prep by drinking a solution of
polyethylene glycol the night before the procedure. People preparing for surgery are also instructed to abstain from food or drink (an
NPO order after midnight on the night before the procedure), to minimize the effect of stomach contents on pre-operative medications and reduce the risk of aspiration if the person vomits during or after the procedure. However,
medical specialty professional organizations recommend against routine pre-operative
chest x-rays for people who have an unremarkable medical history and presented with a physical exam which did not indicate a chest x-ray.
Preparing for surgery A surgical team may include a surgeon, anesthetist, a circulating nurse, and a "scrub tech", or surgical technician, as well as other assistants who provide equipment and supplies as required. While informed consent discussions may be performed in a clinic or acute care setting, the pre-operative holding area is where documentation is reviewed and where family members can also meet the surgical team. Nurses in the preoperative holding area confirm orders and answer additional questions of the family members of the patient prior to surgery. In the pre-operative holding area, the person preparing for surgery changes out of their street clothes and are asked to confirm the details of his or her surgery as previously discussed during the process of informed consent. A set of vital signs are recorded, a peripheral
IV line is placed, and pre-operative medications (antibiotics, sedatives, etc.) are given. When the patient enters the operating room and is appropriately anesthetized, the team will then position the patient in an appropriate
surgical position. If hair is present at the surgical site, it is clipped (instead of shaving). The skin surface within the
operating field is cleansed and prepared by applying an
antiseptic (typically
chlorhexidine gluconate in alcohol, as this is twice as effective as
povidone-iodine at reducing the risk of infection).
Sterile drapes are then used to cover the borders of the
operating field. Depending on the type of procedure, the cephalad drapes are secured to a pair of poles near the head of the bed to form an "ether screen", which separate the
anesthetist/
anesthesiologist's working area (unsterile) from the surgical site (sterile).
Anesthesia is administered to prevent
pain from the trauma of cutting, tissue manipulation, application of thermal energy, and suturing. Depending on the type of operation, anesthesia may be provided
locally, regionally, or as
general anesthesia.
Spinal anesthesia may be used when the surgical site is too large or deep for a local block, but general anesthesia may not be desirable. With local and spinal anesthesia, the surgical site is anesthetized, but the person can remain conscious or minimally sedated. In contrast, general anesthesia may render the person unconscious and paralyzed during surgery. The person is typically
intubated to protect their airway and placed on a
mechanical ventilator, and anesthesia is produced by a combination of injected and inhaled agents. The choice of surgical method and
anesthetic technique aims to solve the indicated problem, minimize the risk of complications, optimize the time needed for recovery, and limit the
surgical stress response.
Intraoperative phase The intraoperative phase begins when the surgery subject is received in the surgical area (such as the
operating theater or surgical
department), and lasts until the subject is transferred to a recovery area (such as a
post-anesthesia care unit). An incision is made to access the surgical site.
Blood vessels may be clamped or
cauterized to prevent bleeding, and retractors may be used to expose the site or keep the incision open. The approach to the surgical site may involve several layers of incision and dissection, as in abdominal surgery, where the incision must traverse skin, subcutaneous tissue, three layers of muscle and then the peritoneum. In certain cases,
bone may be cut to further access the interior of the body; for example, cutting the
skull for
brain surgery or cutting the
sternum for
thoracic (chest) surgery to open up the
rib cage. Whilst in surgery
aseptic technique is used to prevent infection or further spreading of the disease. The surgeons' and assistants' hands, wrists and forearms are washed thoroughly for at least 4 minutes to prevent germs getting into the operative field, then sterile gloves are placed onto their hands. An antiseptic solution is applied to the area of the person's body that will be operated on. Sterile drapes are placed around the operative site. Surgical masks are worn by the surgical team to avoid germs on droplets of liquid from their mouths and noses from contaminating the operative site. Work to correct the problem in body then proceeds. This work may involve: • excision – cutting out an organ, tumor, or other tissue. •
resection – partial removal of an organ or other bodily structure. • reconnection of organs, tissues, etc., particularly if severed. Resection of organs such as intestines involves reconnection. Internal
suturing or stapling may be used. Surgical connection between blood vessels or other tubular or hollow structures such as loops of intestine is called
anastomosis. • reduction – the movement or realignment of a body part to its normal position. e.g. Reduction of a broken nose involves the physical manipulation of the bone or cartilage from their displaced state back to their original position to restore normal airflow and aesthetics. •
ligation – tying off blood vessels, ducts, or "tubes". •
grafts – may be severed pieces of tissue cut from the same (or different) body or flaps of tissue still partly connected to the body but resewn for rearranging or restructuring of the area of the body in question. Although grafting is often used in cosmetic surgery, it is also used in other surgery. Grafts may be taken from one area of the person's body and inserted to another area of the body. An example is
bypass surgery, where clogged blood vessels are bypassed with a graft from another part of the body. Alternatively, grafts may be from other persons, cadavers, or animals. • insertion of
prosthetic parts when needed. Pins or screws to set and hold bones may be used. Sections of bone may be replaced with prosthetic rods or other parts. Sometimes a plate is inserted to replace a damaged area of skull.
Artificial hip replacement has become more common.
Heart pacemakers or
valves may be inserted. Many other types of
prostheses are used. • creation of a
stoma, a permanent or semi-permanent opening in the body • in
transplant surgery, the donor organ (taken out of the donor's body) is inserted into the recipient's body and reconnected to the recipient in all necessary ways (blood vessels, ducts, etc.). •
arthrodesis – surgical connection of adjacent bones so the bones can grow together into one.
Spinal fusion is an example of adjacent
vertebrae connected allowing them to grow together into one piece. • modifying the
digestive tract in
bariatric surgery for
weight loss. • repair of a
fistula,
hernia, or
prolapse. • repair according to the
ICD-10-PCS, in the Medical and Surgical Section 0, root operation Q, means restoring, to the extent possible, a body part to its normal anatomic structure and function. This definition, repair, is used only when the method used to accomplish the repair is not one of the other root operations. Examples would be
colostomy takedown,
herniorrhaphy of a
hernia, and the
surgical suture of a
laceration. • other procedures, including: :*clearing clogged ducts, blood or other vessels :*removal of calculi (stones) :*draining of accumulated fluids :*
debridement – removal of dead, damaged, or diseased tissue
Blood or blood expanders may be administered to compensate for blood lost during surgery. Once the procedure is complete,
sutures or
staples are used to close the incision. Once the incision is closed, the anesthetic agents are stopped or reversed, and the person is taken off ventilation and
extubated (if general anesthesia was administered).
Postoperative care After completion of surgery, the person is transferred to the
post anesthesia care unit and closely monitored. When the person is judged to have recovered from the anesthesia, they are either transferred to a surgical ward elsewhere in the hospital or discharged home. During the post-operative period, the person's general function is assessed, the outcome of the procedure is assessed, and the surgical site is checked for signs of infection. There are several risk factors associated with postoperative complications, such as immune deficiency and obesity. Obesity has long been considered a risk factor for adverse post-surgical outcomes. It has been linked to many disorders such as obesity
hypoventilation syndrome,
atelectasis and pulmonary embolism, adverse cardiovascular effects, and wound healing complications. If removable skin closures are used, they are removed after 7 to 10 days post-operatively, or after healing of the incision is well under way. It is not uncommon for
surgical drains to be required to remove blood or fluid from the surgical wound during recovery. Mostly these drains stay in until the volume tapers off, then they are removed. These drains can become clogged, leading to
abscess. Postoperative therapy may include
adjuvant treatment such as
chemotherapy,
radiation therapy, or administration of
medication such as
anti-rejection medication for transplants. For postoperative nausea and vomiting (PONV), solutions like saline, water, controlled breathing placebo and aromatherapy can be used in addition to medication. Other follow-up studies or
rehabilitation may be prescribed during and after the recovery period. A recent post-operative care philosophy has been early ambulation. Ambulation is getting the patient moving around. This can be as simple as sitting up or even walking around. The goal is to get the patient moving as early as possible. It has been found to shorten the patient's length of stay. Length of stay is the amount of time a patient spends in the hospital after surgery before they are discharged. In a recent study done with lumbar decompressions, the patient's length of stay was decreased by 1–3 days. The use of
topical antibiotics on surgical wounds to reduce infection rates has been questioned. Antibiotic ointments are likely to irritate the skin, slow healing, and could increase risk of developing
contact dermatitis and
antibiotic resistance. The review also did not find conclusive evidence to suggest that topical antibiotics increased the risk of local skin reactions or antibiotic resistance. Postoperative pain affects an estimated 80% of people who underwent surgery. While pain is expected after surgery, there is growing evidence that pain may be inadequately treated in many people in the acute period immediately after surgery. It has been reported that incidence of inadequately controlled pain after surgery ranged from 25.1% to 78.4% across all surgical disciplines. Preoperative factors that have been found associated with poorer postoperative pain control include younger age, female sex, smoking, sleep difficulties, symptoms of depression and anxiety, higher BMI, preoperative pain and use of preoperative analgesia. There is insufficient evidence to determine if giving opioid pain medication pre-emptively (before surgery) reduces postoperative pain or the amount of medication needed after surgery. Most people are discharged from the hospital or surgical center before they are fully recovered, with medical reasons including faster recovery and lowered risk of
hospital-acquired infection. The recovery process may include complications such as
postoperative cognitive dysfunction and
postoperative depression. ==Epidemiology==