Improved Outcomes in Colon and Rectal Surgery part 9 ppt

Downsides to epidurals have consistently been their potential for increasing urinary retention and hypotension, higher costs, and perhaps decreased patient sat-isfaction, with no change

a narcotic-sparing role In a study of over 1,000 patients, the

addi-tion of ketorolac to standard intravenous morphine significantly

reduced the overall postoperative morphine requirements, and

low-ered side effects both directly attributable to the narcotic (mental

status, pulmonary) as well as gastrointestinal function (ileus,

nau-sea, vomiting).(4) The anti-inflammatory action of these agents,

especially when used on a set schedule, may be most beneficial for

the pain associated with the musculoskeletal trauma of the incision,

allowing a significant reduction in pain without the untoward side

effects associated with narcotic use

Pain following anorectal surgery can be quite debilitating and

is often cited by patients as a primary deterrent toward

undergo-ing needed procedures such as hemorrhoidectomy.(5) In addition

to the local trauma associated with resection, pain following anal

canal procedures is often attributed to anal sphincter spasm This,

in combination with the constipation and hard stools often

asso-ciated with narcotic use, results in additional pain and suffering

once return of bowel function commences As in the laparotomy

literature, recent trials have shown a marked decrease in the

nar-cotic requirements using ketorolac and other NSAIDs

periopera-tively for anorectal surgery.(6)

Local anesthesia, which has been commonly employed in the

field of anorectal surgery, has recently been expanded to continued

use postoperatively following abdominal procedures As a primary

modality during anorectal procedures, it has been shown to be

effec-tive and safe, with or without the addition of deep intravenous

seda-tion, and provides the additional benefit of less time in the recovery

room.(7, 8) As an adjunct following laparotomy, a local anesthetic

agent is applied via continuous infusion to the midline wound

through a set of subcutaneous catheters placed at the time of surgery

(9) Despite mixed results, some prospective data does demonstrate

a decreased narcotic requirement and improved perioperative

recov-ery, including earlier ambulation, in the absence of significant overall

postoperative pain score differences.(10, 11) As increased

experi-ence is gathered using this modality, further data may determine its

appropriate place in the analgesia armamentarium

Another method commonly employed is epidural anesthesia,

which works through inhibiting ascending neural pathways as well

as the sympathetic output from the spinal cord This dual action

provides the beneficial effects of not only improved pain control,

but also has been shown to aid with earlier return of bowel function

through its sympathectomy Various agents have been described

for use in epidurals, with the mainstays being local anesthetics and

narcotics In a meta-analysis of sixteen randomized controlled

tri-als from 1987 to 2005 comparing the use of epidurtri-als to

paren-teral controlled analgesia, Marret and colleagues found epidurals

were associated with improved analgesia and overall decreased

ileus, with only side effects such as pruritis and labile blood

pres-sure significantly associated with epidural use.(12) Gendall and

colleagues confirmed these findings in a recent review of the

lit-erature, again demonstrating that epidural anesthesia improves

functional recovery and pain relief, while potentially decreasing

pulmonary complications.(13) While the epidural is in place, the

anesthesiologist often manages all of the pain medications,

per-forming comprehensive pain management When the epidural

is removed, the management returns to the surgeon The use of

anticoagulation for deep venous thrombosis (DVT) prophylaxis

and epidural placement/removal must be coordinated between the surgeon and anesthesiologist Downsides to epidurals have consistently been their potential for increasing urinary retention and hypotension, higher costs, and perhaps decreased patient sat-isfaction, with no change in length of stay.(14) Despite these nega-tive attributes, epidural use for colorectal surgery provides the potential for outcome improvement in analgesia and functional recovery, and is a very useful alternative for pain control following abdominal and large pelvic procedures

Furthermore, gabapentin, a medication that was originally designed for the treatment of epilepsy, has evolved as a treatment for mainly neuropathic pain, and has been studied extensively in both the pre- and postoperative settings Although the exact mecha-nism of action is unknown, it is believed to act through N-gated calcium channels, and focus has been on both providing improved perioperative analgesia as well as narcotic-reducing effects.(15) Unfortunately, its use as an independent entity has been less effica-cious, and it has not been extensively studied for either colorectal

or anorectal surgery.(16) Both it, and a newer analog pregabalin, have been shown to decrease the need for opioids and thus reduce side effects such as nausea, vomiting, and urinary retention in other surgical arenas While further study awaits recommendations spe-cifically for use in the realm of colon and rectal surgery, these medi-cations, along with standard postoperative regimen of increased oral fluid intake, fiber, stool softeners, sitz baths, and avoidance of constipation all aid in recovery from anorectal surgery

Most importantly, these varying agents all operating through different mechanisms convey the needed concept for the surgeon

to use a multimodality approach to ensure successful perioperative pain management

Figure 8.1 Thumbtack occlusion of a bleeding basivertebral vein.

bleedinG

Bleeding complications with any operation can be categorized

by many different methods including intraoperative,

postopera-tive, anastomotic bleeding, and gastrointestinal bleeding, such

as stress-related ulcers One of the most important factors for

the surgeon is to preoperatively assess and determine the risk

of bleeding A thorough history and physical examination with

emphasis on a personal or family history of bleeding tendency

is crucial to identification and subsequent evaluation of those

patients at risk, and should be completed before embarking on

surgery Questions should focus on any predisposition for easy

bleeding or bruising, inability to clot even with mild cuts, or

his-tory of prior transfusions following surgeries, to identify certain

patients that require further evaluation Preoperative laboratory

evaluation should include a complete blood count, coagulation

panel (PT, PTT, INR), and platelet count For those patients at

increased risk, a more detailed analysis of platelet and clotting

cascade function to include bleeding times, mixing studies, or

evaluation by a hematologist may be appropriate

Perioperative bleeding with colorectal surgery depends in many

aspects on the surgical procedure performed Whereas bleeding

rates following hemorrhoidectomy range from 2% to 6%, those

fol-lowing major abdominal operations such as total mesorectal

exci-sion (TME) for rectal cancer have been shown to have much higher

blood loss estimates, with transfusion requirements reported in

up to 43–73% of patients.(17–20) The most common causes for

postoperative hemorrhoidal bleeding are technical failure (failed

knot) within the first 24 hours, and infection with erosion at

7 days Despite this, bleeding following hemorrhoidectomy is

often able to be controlled either without surgical intervention or

with simple suture ligation in the outpatient setting

In contrast, bleeding following major abdominal or pelvic

procedures can mandate return to the operating room with

corresponding physiological changes that may lead to

cardio-pulmonary complications Yet, with the emergence of emphasis

on decreased mandatory transfusion requirements, and

techno-logical advancements such as improved minimally invasive

tech-niques, transfusion rates are decreasing and blood loss has also

decreased In a study of 147 patients in a case-matched

compara-tive analysis between open and laparoscopic colectomies, Kiran

and colleagues found that both estimated blood loss and

peri-operative transfusion rates were significantly higher in the open

group.(21) Timing of the onset of bleeding also provides some

insight as to its etiology Early postoperative bleeding is typically

from a technical error at the time of operation.(22) Late

bleed-ing, which tends to present days to weeks after surgery, (though

not outside the realm of technical problems) is more commonly

secondary to patient factors such as an underlying bleeding

ten-dency, concomitant coagulopathy, or spontaneous rupture or

hemorrhage It is worth noting that the risk of severe bleeding

such as after a two or three quadrant hemorrhoidectomy, despite

being small (2–6%), can be catastrophic.(5, 19) Therefore, it is

imperative that the possibility of bleeding is discussed with all

patients preoperatively, no matter how minor of a surgical

proce-dure the patient is undergoing

Although uncommon, massive presacral bleeding during pelvic

dissection can result in hemodynamic instability and even death

Injury is secondary to dissection outside the avascular plane Initial management includes packing and leveling the patient on the oper-ating room table, along with continued resuscitation This is effective for most patients within 20–30 minutes Multiple other methods have described including electrocautery, suture ligation, sacral thumbtacks (Figure 8-1), muscle fragment welding, placement of tissue expand-ers or cyanoacrylate adhesives, topical hemostatic agents, and endo-scopic tacking devices.(23–28) Although the presacral veins may be injured, continued bleeding nonresponsive to initial management

is most commonly from the basivertebral veins through the sacral foramina.(24, 29, 30) When all else fails, pelvic packing, peritoneal closure, warming, and resuscitation in the ICU with return to the operating room 24–48 hours later may be required Thus, emphasis

on proper technique, knowledge of the pertinent anatomy, and com-prehension of options to immediately consider when things do go awry are all important to decrease perioperative bleeding complica-tions and subsequent clinical complicacomplica-tions

infection Surgical-Site Infection (SSI)

Surgical site infections continue to be a major source of cost and morbidity despite a strong emphasis on proper selection, timing and duration of perioperative antibiotics Infections can be clas-sified as surgical site infections, general postoperative infections such as pneumonia and urinary tract (which will be covered in separate sections), and infectious processes that deal specifi-cally with the operation itself (i.e., anastomotic leaks, abscesses) Although multiple different patient and surgical factors contrib-ute to the development of postoperative infections, development

of any infectious complication results in increased patient suf-fering, length of stay, and delayed recovery Additionally, hospital costs encompassing antibiotics, interventional procedures, nurs-ing support, and surgical intervention contribute to drivnurs-ing up overall healthcare system costs

In simple terms, our skin and mucosal lining remain the primary defense mechanisms against infectious sources With surgery, the breach in these protective layers, along with manipu-lation of the bowel and potential spillage of stool from various colorectal procedures lead to increased rate of infections Those patients with an extensive component of cellulitis, characterized

by leukocytic infiltration of the dermis, bacterial presence, and localized inflammatory response, typically require the addition of antibiotics, especially in patients with immunosuppresion, diabe-tes mellitus and the elderly With the emergence of methicillin-resistant Staphylococcus aureus (MRSA) and other multimethicillin-resistant bacteria, it is imperative for the surgeon to help control the emer-gence of these more virulent pathogens by avoiding prolonged usage of antibiotics and changing antibiotics once the pathogens are cultured and appropriate sensitivity to antibiotics is known With such a drastic rise in the incidence of MRSA, some hospitals are performing preadmission screening cultures for this patho-gen Thus, if there is an emergence of an active MRSA infection

in the postoperative period, the patient most likely brought the infection into the hospital with them Its presence then is not a result of failure of the surgeon or hospital personnel to follow protocol prevention From a surgical perspective, proper wound

care, drainage of abscesses, and debridement of any necrotic

tis-sue, where appropriate, remain important adjuncts to the

medi-cal management of infections Aspiration and drainage under

imaging can often be used to convert an urgent reexploration to

either an elective procedure or provide the ability to avoid a

reop-eration altogether

In addition to proper surgical technique that avoids

con-verting a clean contaminated to a dirty case, identification of

at-risk patients can aid in early identification and treatment of

infectious complications In a review of 428 patients

specifi-cally undergoing colorectal operations, surgical site infections

were independently associated with increased body mass index

(BMI) (odds ratio [OR] 1.07), and those in which a revision/

creation/or takedown of a stoma was involved (OR = 2.2).(31)

In addition, with the emerging pandemic of obesity

through-out the world, increased BMI has been found to be associated

with not only higher rate of surgical site infections, but also is

an independent predictor of wound dehiscence, herniation, and

anastomotic leak.(32)

Different methods have been employed to attempt to decrease

the incidence of surgical site infections There is some debate in

the literature regarding the duration of antibiotic use for elective

colon and rectal surgery Although preoperative use of

intrave-nous antibiotics to ensure adequate tissue concentrations at the

time of incision has become standard of care, there is some

con-troversy regarding the use of a single dose versus multiple doses

Fujita and colleagues performed a study including almost 400

patients undergoing elective resection of colorectal cancer and

found that the three dose regimen of an every 8 hour, second

generation cephalosporin (i.e., 24-hour perioperative coverage)

significantly decreased the incidence of surgical site infections

over a single preoperative dose (4.3% vs 14.2%, p = 0.009).(33)

However, organ or space SSI and other postoperative infectious

complications did not differ between the two groups, and has

similarly been not significantly different in many other studies

The practice of adding oral antibiotics has similarly

contradic-tory evidence, with large prospective randomized trials

demon-strating no decrease in infectious complications, while increasing

the rates of nausea, pain, and noncompliance.(34, 35) Yet, other

authors including a large prospective randomized trial and

meta-analysis of 13 studies demonstrated the addition of oral

antibiot-ics to systemic antibiotantibiot-ics was associated with a higher rate of

prevention of surgical site infections.(36, 37) Proponents cite

the ability of the oral antibiotics to decrease the bacterial load

in the colon, as well as the marked increase of colonic bacterial

isolates from the infected surgical wounds as evidence and

ratio-nale for its use With such varying opinions, it is up to the

indi-vidual surgeon to evaluate the literature and determine the best

approach as it applies to their patient population Finally, besides

the proper use and timing of preoperative antibiotics,

supple-mental postoperative high dose oxygen (80%) has been shown

to reduce surgical site infections by approximately 6–40%.(38, 39)

Through suggested mechanisms, including more efficient

electron-transport chain off-loading and improved neutrophil function,

postoperative high-flow oxygen in the immediate recovery period

has become part of a standardized postoperative pathway for many

institutions Finally, fewer complications may be associated with

maintaining perioperative normothermia in patients undergo-ing colorectal surgery Employundergo-ing methods such as preoperative warming with bear-hugger devices, use of warm blankets and fluids, and avoiding prolonged or unnecessary exposure, may all result in less SSI

urinary tract infection and retention

Urinary tract infections are the leading cause of nosocomial infections, accounting for ~40% of all infections, of which 80% are associated with transurethral catheter placement.(40) The dilemma remains how to significantly reduce this rate, especially

in light of the chronic use of urinary catheters during colorectal procedures A recent Cochrane review evaluating the use of anti-biotics during short-term catheter use demonstrated there was

a paucity of evidence that antibiotic prophylaxis was any better than treating patients when clinically symptomatic While it did show some weaker evidence that bacteriuria, pyuria, and gram-negative bacteria are all reduced following antibiotic use over 24 hours or until catheter removal, none of these studies specifically focused on the colon and rectal patient In addition, there was limited data on cost or subsequent development of multiresis-tant organisms, and most patients undergoing colorectal sur-gery receive perioperative antibiotics to cover bowel flora Thus, caution needs to be taken when determining the applicability of these results to colorectal surgical patients Following rectal sur-gery, urinary tract infection in part depends on the clinical prac-tice of the surgeon regarding length of time of bladder catheter drainage In a study comparing catheter removal at 1 and 5 days following rectal resection, Benoist and colleagues found urinary tract infections to be increased in those patients with catheters in

for 5 days versus those who removed after 1 day (42% vs 20%, p

< 0.01).(41) Increases in urinary tract infection with prolonged drainage must be balanced with voiding dysfunction with early catheter removal

Unfortunately, urinary retention remains a well-known com-plication of colorectal and anorectal surgery, as well as a result of the spinal anesthesia commonly used during these operations.(42)

In the Benoist study, urinary retention was significantly increased

in those with the catheter present for only 1 day of postoperative

drainage over the 5-day cohort (25% vs 10%, p < 0.05), especially

amongst those with tumors of the low rectum.(41) Following pel-vic surgery, this may be, in part, secondary to third spacing and edema around the urethra following disruption of these tissue planes Thus, in abdominal surgery, where the dissection does not proceed below the peritoneal reflection, this may lower the rate

of dysfunction The authors concluded that 1 day of drainage is adequate for most patients, although for patients undergoing lower resections, longer periods of drainage may be optimal Changchien and associates in a review of 2,355 patients with colorectal cancer found urinary retention to be significantly associated with mul-tiple factors to include older age, history of lung disease, rectal cancer, longer operations, and additional pelvic procedures such

as hysterectomy or cystectomy.(43) Additionally, male gender, American Society of Anesthesiologists’ (ASA) score of 2 or 3, rectal cancer, use of a pelvic drain, and pelvic infection were indepen-dently associated with prolonged urinary dysfunction, defined as continued problems over one month postoperatively To lessen

the higher rates associated with transurethral catheter placement,

some authors have also advocated suprapubic catheter drainage In

patients undergoing pelvic surgery, this has been associated with

similar voiding dysfunction rates, but fewer infectious

complica-tions than the traditional transurethral route.(44, 45)

Following anorectal surgery, urinary retention rates have

been reported to be up to 50%.(46) Multiple methods that have

attempted to decrease this rate have limited perioperative fluid, use

of local versus spinal anesthesia, and even use of alpha-adrenergic

blockade preemptively.(46) Although the latter did not seem to

sig-nificantly affect rates of voiding dysfunction, both fluid restriction

and adequate pain control have consistently been shown to have a

positive effect at decreasing this difficult problem.(47, 48) Toyonaga

and associates, in a prospective study of over 2000, patients found

independent predictors significantly associated with the

develop-ment of urinary retention following anorectal surgery were female

sex, prior urinary difficulties, diabetes mellitus, intraoperative

flu-ids over 1 L, and prolonged need for postoperative analgesics.(48)

Although urinary retention is known to increase overall length of

hospital stay, (42) careful patient education and strict fluid control

have allowed most anorectal surgeries to be performed in an

ambu-latory setting with a low rate of return for urinary catheterization

(49) Additional use of agents such as NSAIDs and Ketorolac may

minimize narcotic use and increase the success rate by avoiding this

complication in an outpatient setting.(6) Surgeons therefore need

to be in constant communication with their anesthesia

counter-parts to discuss excessive fluids and proper analgesia, as many are

unaware of the potential downfall of these common practices

atelectasis

Prevention

Basic principles of airway clearance, avoidance of splinting and

alveolar collapse, while preserving functional residual capacity

and pulmonary reserve remain important components of proper

postoperative pulmonary toilet As a part of the “5 W’s” of the

postoperative fever, “wind” as it relates to atelectasis reminds

phy-sicians that optimizing ventilation and oxygenation are keys to

successful recovery, and are subsequently passed down to

succes-sive generations of training surgeons (as much as absolute truth

as ancient lore) The fundamental principle behind avoidance of

atelectasis has been shown to be successful in pulmonary processes

ranging from cystic fibrosis and acute spinal cord injury to

post-operative esophagectomy.(50–52) As such, factors such as head of

bed elevation, early ambulation, and the ever-present incentive

spirometer have become the mainstays of postoperative inpatient

care However, a recent Cochrane review of incentive spirometry

use in the postcoronary artery bypass graft population with 443

participants in 4 trials found no difference in pulmonary

compli-cations amongst incentive spirometry, positive pressure use

con-tinuous positive airway pressure (CPAP), bilevel positive airway

pressure (BIPAP), or simple preoperative patient education.(53)

Furthermore, a meta-analysis with 14 trials over a 26-year period

evaluating the use of incentive spirometry, positive pressure, and

deep breathing following upper abdominal surgery to prevent

postoperative pulmonary complications, also demonstrated no

statistically significant difference between these modalities and no

therapy alone.(54) Pasquina and colleagues performed a review

of 35 trials evaluating the use of respiratory physiotherapy after abdominal surgery and found that only in one study was the incidence of pneumonia decreased In another study atelectasis decreased from 77% to 59% using pulmonary toilet methods of deep breathing, cough, and postural drainage.(55) They concluded that there are only a few trials that support its use, and the routine use of respiratory physiotherapy does not seem warranted based

on data alone Despite these large reviews, atelectasis is known

to be present in anesthetized patients in the dependent portions

of the lungs and has been shown to contribute to decreased lung compliance, worse oxygenation, increased pulmonary vascular resistance, and shunting.(56) It seems at worst that the practice of employing methods to decrease atelectasis is not harmful, and at best, may help out to a small degree with avoidance of pulmonary complications, and therefore, it is our continued practice

Pneumonia

There is little data in the literature that directly addresses the development of pneumonia following colorectal or anorectal sur-gery As stated above, the degree to which atelectasis and proper pulmonary toilet corresponds to the development of pneumo-nia is debatable One thing that is clear is that development of postoperative pneumonia is independently associated with worse outcomes Therefore, both prevention and early recognition and treatment, are key components to ensuring optimal outcomes Johnson and colleagues found in a study of 180,359 patients that postoperative respiratory failure (defined as mechanical ventila-tion for longer than 48 hours after initial surgery or unantici-pated reintubation) was found in 5,389 (3.0%) of patients and was associated with an increased in hospital morbidity, cost, and late mortality.(57) Additionally, factors that were found to

be independently associated with the development of this was higher ASA classification, emergency operations, more complex surgery, sepsis, older age, congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD), and smoking These, along with a history of obesity and obstructive sleep apnea, man-date a need for careful postoperative monitoring and aggressive pulmonary toilet Many of the patients, especially with underly-ing malignancy, have these comorbidities, and speak to the com-plexity of operations and need for close surveillance to avoid this feared complication

deep venous thrombosis

Deep venous thrombosis (DVT) and its embolic corollary, pul-monary embolism (PE), are a significant source of morbidity and mortality in the perioperative period Due to the predominance of abdominal and pelvic surgery, colorectal surgery carries a higher risk

of these postoperative complications than other general surgical pro-cedures Yet, despite so much emphasis, DVT and PE continue to be the most common cause of preventable deaths during in-hospital admission, accounting for 1 out of every 4 hospitalized patients deaths.(58, 59) More concerning, over 50% of all DVTs are asymp-tomatic, while the vast majority of PEs are detected only after death (58) Since Virchow’s original description of stasis, hypercoaguability, and endothelial damage as risk factors, large epidemiological studies have found an increase in the development of symptomatic venous

thromboembolism in the perioperative period to be associated with

male gender, malignancy, trauma, immobility, COPD, sepsis, low

hematocrit, low albumin, and major surgery.(60)

One of the major problems with development of a DVT is the lack

of initial clinical signs Patient complaints of pain, swelling, edema,

warmth, and tenderness of the affected limb are often absent.(61)

Those patients that progress onto pulmonary embolism present

many times in the late stages with cardiopulmonary shock and

col-lapse, though often heralded by symptoms such as acute shortness

of breath, dyspnea, pleuritic chest pain, along with tachycardia and

an increasing oxygen requirement Thus, emphasis has been placed

on both prevention and screening Despite its very high

sensitiv-ity and specificsensitiv-ity of over 95%, screening with duplex and color

Doppler sonography, even in high risk patients, in the absence of

symptoms, has been questioned as to its cost-effectiveness.(62, 63)

Part of this may be that although the lower extremities are the most

common site of origin, approximately one-third of patients have

proximal (above popliteal) veins as the site of origin, which are not

visualized well by duplex.(59) Venous ultrasonography remains the

mainstay for diagnosis of deep venous thrombosis, especially when

combined with elevated d-dimer levels The hallmarks of DVT via

ultrasound are both visualization of the clot and more commonly

the inability to compress the venous system under direct pressure

(64) Similarly with the advent of multidetector row helical CT

scan-ners, this has essentially supplanted the pulmonary angiogram as

the procedure of choice for diagnosis of pulmonary embolism, with

sensitivity, specificity, and negative predictive value over 90%, even

for subsegmental pulmonary emboli.(65)

Prophylaxis of venous thrombotic events centers on both

mechanical and medical means The current mainstays for

chemi-cal thromboprophylaxis are unfractionated and low- molecular

weight heparin Unfractionated heparin works through

anti-thrombin III to deactivate anti-thrombin and other factors in the

clotting cascade Concerns about increased bleeding events as well

as its dose-effect relationship have led many to be wary of its use

Low-molecular weight heparin has enhanced antifactor Xa

activ-ity and more predictable dose-effect relationships.(66) In a recent

Cochrane review addressing the prevention of thromboembolic

complications, the combined use of mechanical graduated

stock-ings with either unfractionated or low molecular heparin was

identified as the optimal prophylaxis.(67) Interestingly, despite the

extensive search, only 3 studies meeting inclusion criteria focused

specifically on colon and rectal surgery That same group

evalu-ated 558 studies, of which 19 met the inclusion criteria, and again

found that unfractionated and fractionated heparin were equally

effective, and the addition of either to compression stockings was

superior to either alone.(68)

As pointed out in the opening challenging case, risk

stratifi-cation continues to be a mainstay for determining the extent of

prophylaxis in these patients Young, healthy patients undergoing

routine anorectal surgery, with minimal patient-specific risk

fac-tors, do not require any therapy other than mechanical means

via graduated compression stockings and/or intermittent

pneu-matic compression boots and early ambulation Those patients

with multiple risk factors and undergoing high risk surgery, such

as pelvic operations, warrant more aggressive means like

unfrac-tionated or low-molecular weight heparin, in addition to the

mechanical devices Timing has been somewhat controversial with some studies demonstrating higher bleeding without undue increase in thrombotic events when given after the surgery and others stating that dosing should begin preoperatively Although this question has yet to be definitively answered based on cur-rent literature, it is well accepted that some form of perioperative, including intraoperative means, has become the standard of care The risk of bleeding with thromboprophylaxis dosing is small, with the majority revolving around injection site ecchymoses or hematoma in up to 7% of cases.(69) More clinically significant bleeding, such as gastrointestinal or intraabdominal bleeding, occurs in <0.5%, and is rarely the cause for cessation of therapy One potential concern that arises frequently in the realm of colorectal surgery is how to treat the patient receiving anticoagu-lation for colonoscopy Recent guidelines have shown that aspirin and other NSAIDs do not need to be withheld, with the rate of postpolypectomy bleeding around 2%.(70) On the other hand, coumadin and other more potent antiplatelet medications (i.e., clopidogrel) are commonly held for 5 to 7 days before the pro-cedure, especially when it is known that a polypectomy or other procedure is likely There is some evidence that the application

of endoclips with polypectomy in anticoagulated patients is safe; however, small sample sizes hinder ability to make broad recom-mendations.(71) Thus, most of the practice is based on guide-lines and less on an abundance of available evidence supporting

or dissuading this practice.(72, 73)

nausea and vomitinG

Though often not deemed as significant or crucial to overall success

of an operation by surgeons, postoperative nausea and vomiting (PONV) can be extremely bothersome for the patient Clearly, the etiology is multifactorial—with surgical, anesthetic, medication, and patient-related factors all contributing significantly Head of bed elevation and early ambulation are minor modifications that may be somewhat helpful More useful, anesthesia providers have found increasing success through prophylaxis for this phenom-enon As a part of that process, identification of those patients at risk is imperative, as universal prophylaxis has not been shown

to be cost-effective.(74) A thorough review of prior surgeries and response to anesthetics may help in identification of these individ-uals Intravenous use of ondansetron, a selective serotonin 5HT3 receptor antagonist, has been shown in multiple randomized trials

to be effective in complete prevention of postoperative emesis in up

to 60–85%, when given before the induction of general anesthesia (75–77) Finally, routine decompression with nasogastric tubes has demonstrated no impact on PONV and has fallen out of favor.(78)

prolonGed ileus

In general, postoperative obstruction can be divided into two broad categories—early and late Early postoperative bowel obstruction is defined as onset of symptoms within thirty days of surgery The majority of early postoperative bowel obstructions are due to para-lytic ileus or adhesions—up to 90 percent in some series, with the remaining possible etiologies including phlegmon, intraabdomi-nal abscess, Crohn’s disease, hernia, volvulus, intussusceptions, and malignancy.(79, 80) Late obstructions are those presenting at any point >30 days following surgery The management of bowel

obstruction including ileus remains a significant burden to

health-care costs In 1994, according to Beck and colleagues, there were

303,836 hospitalizations during which adhesiolysis was performed,

accounting for 846,415 inpatient days and an estimated $1.3 billion

in expenditures.(81) In addition, reoperative surgery in the setting

of early bowel obstruction can prove to be significantly

challeng-ing, as abdominal inflammation and early adhesions create a hostile

environment marked by densely adhered bowel and friable tissues

In order to safely and effectively manage these patients, one must

have an extensive understanding of the various conditions which

may result in prolonged ileus

Like many of the complications discussed in this chapter,

the development of a prolonged ileus has multiple potential

causative factors including hormones, medications and

sur-gical stress Postoperative ileus clinically manifests itself with

abdominal distension, bloating, failure to pass stool or gas,

nau-sea, emesis, and pain Even more concerning, Senagore found

that in addition to the symptoms experienced as a result of the

ileus, delayed surgical wound healing and ambulation,

atelecta-sis, pneumonia, and deep vein thrombosis are all potentially

increased by the development of a postoperative ileus, which

increases hospitalization length of stay and overall costs.(82) The

definition of what constitutes a prolonged ileus widely varies in

the literature and contributes to discrepancies between different

studies In general, when the symptom complex continues for over

7 days following abdominal surgery, most consider this prolonged

and should raise concern for more extensive evaluation

Return of bowel function has multiple parameters that can be

controlled by the provider in the perioperative period For

exam-ple, limiting the amount of intraoperative and postoperative fluid

and sodium has been shown to improve time to passage of flatus

and stool, and result in earlier hospital discharge.(83) In addition,

clinical pathways that include the use of restricted perioperative

intravenous fluids, early oral intake, early ambulation, and

epidu-ral anesthesia, have been shown to significantly decrease length of

stay and perioperative cardiopulmonary complications, although

readmissions are slightly higher.(84) Thus, working through

optimization of all components of postoperative care may

con-tribute more to a successful recovery than primary emphasis on

one factor alone Through entry into a standardized program,

the avoidance of certain variables that negatively affect recovery

for both the intraoperative and postoperative settings can

pro-vide improved reproducible results.(85) A bonus of

implemen-tation of pathways is the ability to help all healthcare providers,

including nursing personnel, to become accustomed to a routine

postbowel resection course Therefore, any deviations from this

can be recognized more readily, allowing intervention before the

patient enters a more severe or septic state

A thorough history and physical examination help distinguish

some of the benign causes of obstruction and aid in differentiating

this from a prolonged ileus For example, the history in a patient

with Crohn’s disease or prior radiation therapy can provide just

as many clues as to the etiology of the obstruction, such as

pos-sible stricture, or an obvious hernia detected on physical

exami-nation As patients often present with concomitant dehydration

and electrolyte abnormalities, placement of a nasogastric tube,

with appropriate fluid resuscitation, and correction of electrolyte

abnormalities should occur while the work-up is in progress Plain film radiographs may confirm dilated small bowel loops with stair-stepping air-fluid levels, but usually do not assist in defin-ing the underlydefin-ing etiology Despite their frequent use, numerous studies quote a poor sensitivity for plain abdominal radiographs

in diagnosis of small bowel obstruction, ranging from 13% for low grade obstruction to 50–60% for high grade obstructions (86) CT may give anatomical information outside of the bowel wall itself that may help with accurate diagnosis Caution should

be used in giving oral contrast for the patient with high grade ileus or obstruction, and in general, should be avoided

Newer pharmacotherapeutic endeavors, such as the peripher-ally acting mu-opioid receptor antagonist, alvimopan, have been shown to reduce the incidence of postoperative ileus, nasogas-tric tube insertion, time to gastrointestinal recovery, and overall hospital length of stay.(87–89) Further studies are still ongoing

to evaluate whether its safety profile is acceptable for wide-scale clinical use Other methods that have been studied in attempt to shorten bowel function return include prokinetic agents such as erythromycin and cisapride, although the results have been mixed Erythromycin, a motilin agonist, has been shown in the past to be effective for upper gastric and pancreatic surgery, especially with regard to promotion of gastric emptying In a randomized double-blind placebo study of 134 patients, erythromycin was not shown

to affect clinically relevant outcomes such as time to intake of solid foods, nausea rate, or length of stay.(90, 91) Similarly, cisapride, before its removal from the market secondary to cardiac toxicity, did show some, albeit limited, clinically significant improvements (92–94) Thus, for hindgut surgery, prokinetic agents have not yet been shown to make a clinically relevant difference

Probably the most important factor that has been shown to make a difference in reducing ileus is postoperative clinical pathways that include early oral feeding.(95) A recent Cochrane review by Andersen et al including 13 randomized controlled trials and over 1,100 patients, evaluated the use of early feeding and the development of complications and found early feeding

is safe, may reduce postsurgical complications, and concluded there is no advantage to withholding oral intake.(96) Opponents

of this practice cite a lack of a consistent definition of what early feeding encompasses As such, although many surgeons prefer to advance the postoperative diet slowly, it does seem clear that the recovery of gastrointestinal function as evidenced by first bowel movement or flatus and tolerance of an oral diet in the early post-operative setting are independent of each other, and the practice

of early resumption of diet is safe.(97)

retained foreiGn bodies

In any complex surgical procedure there exists a potential for items

to be unknowingly left in body cavities.(98) To minimize this risk, current standards require all sponges, needles, surgical instru-ments, equipment, and items small enough to be misplaced be counted before the procedure and one or two times after the com-pletion of the procedure to confirm that all items are accounted for These activities are usually performed and documented by the operating room nurses and technicians; however, the surgeon is ultimately responsible and should conduct each operation so as to minimize the risk of misplaced foreign bodies In accordance with

this goal, most surgeons, avoid using small Ray-tec sponges in the abdomen and avoid placing laparotomy sponges in areas that are hard to visualize If sponges must be used to pack areas, the sponge marker should be left in an obvious area, or a ring or clamp may

be attached to the sponge Most important is a through explo-ration of the entire operative field, which should be performed routinely before closing the incision Items used during the opera-tion that have the potential to be easily lost should be radiopaque

or contain a radiopaque marker (e.g., Ray-tec sponges and Silastic drains) Figures 8.2 and 8.3 demonstrate the radiologic view of several common surgical items Plain radiographs are often the best for identifying the radiopaque markers incorporated into these items; The markers may be much less obvious on studies such as CT scans (Figures 8.4a and b)

If an instrument, sponge, or needle count is not correct, several actions are indicated All the sponge wrappers and suture pack-ages should be counted to confirm the accuracy of the original count The entire operating room, and especially the trash bags and floor under the operating table, should be searched for the misplaced item Simultaneously, the surgeon should inspect the operative field thoroughly for the missing item If the missing item cannot be located, a radiograph of the entire operating field

Figure 8.2 Radiograph demonstrating radoopaque markers Left to right

Laparotomy sponge, Ray-tec sponge The upper image is flattened, whereas the

lower image demonstrates the radiologic view when the item is crumpled.

Figure 8.3 Radiograph of (left to right) Jackson-Pratt drain, Penrose drain,

nasogastric tube.

Figure 8.4 (A) CT scan of patient with a retained Ray-tec sponge Image is the

inferior cut of the study The upper edge of the Ray-tec marker is demonstrated

as white dots lines between the bladder (filled with contrast) and the sacrum (B) Pelvic radiograph of the same patient demonstrating Ray-tec marker in pelvis.

(A)

(B)

should be obtained before closure of the body cavity to identify

any radiopaque object and minimize the morbidity of locating

the missing item Because of the potential for human error, a

“correct” instrument, needle, or sponge count does not absolutely

exclude the presence of a foreign body Therefore, each member

of the team must maintain a high index of suspicion

A sponge or other foreign body left in a body cavity can

pres-ent or be idpres-entified in a number of ways The foreign body may

be seen on a radiograph obtained for other reasons, or the patient

may develop symptoms that lead to the need for radiographs or

an exploratory procedure Symptoms may be infectious (fever,

elevated white cell count, wound infection, or abscess) or

inflam-matory (ileus, tenderness, mass effect) For any postoperative

patient with unusual or unexplained symptoms, radiographs

should be included in the evaluation

Finding a retained foreign body is unusually an indication for

an urgent exploratory procedure The exception may be

asymp-tomatic patient with a retained small needle The morbidity

associ-ated with localizing and removing a small needle must be weighed

against the potential risk of leaving it alone, and the patient can

assist in this decision Review of biplanar radiographs may assist

in localizing a retained item, and early identification will minimize

the morbidity associated with the object’s removal Retention of

operative foreign bodies is uncommon, and a surgical team that

adheres to careful practices should avert its occurrence

“time out” and sided surGery concerns

Wrong-side/wrong site, wrong-procedure, wrong-patient adverse

events (WSPEs) constitute some of the worst medical errors that

cli-nicians and patients experience These events often result in patient

harm and litigation, but literature on frequency and root causes

is limited.(99) The Institute of Medicine report To Err Is Human

painted a broad picture of the magnitude of medical errors in the

United States and gave directions for safety improvements.(100)

While, sided surgery is less of a concern in colorectal patients,

incor-rect surgery due to inadequate lesion location remains a challenge In

July 2004, the Joint Commission on the Accreditation of Healthcare

Organizations (JCAHO) implemented the universal protocol for the

prevention of WSPEs.(101) The protocol uses preoperative

verifica-tion of patient, site, and procedure, marking the operative site, and

a time-out immediately before starting the procedure Prevention of

WSPEs requires new and innovative technologies, reporting of case

occurrence, and learning from successful safety initiatives (such as

in transfusion medicine and other high-risk nonmedical industries),

while reducing the shame associated with these events

future directions

As the push to not only prevent complications but detect them

earlier continues to expand, molecular markers may become an

increasingly utilized component Welsch and associates evaluated

the use of C-reactive protein (CRP) in the postoperative course

of 383 rectal resections with primary anastomosis in patients

with rectal cancer and found that using a cutoff of levels above

140 mg/dl on postoperative days 3 and 4 was associated with a

sensitivity of 80 and 54% respectively and specificities of 81 and

92%, respectively, for the presence of all infectious complications

(102) Although this is just one example of a vast field, it highlights

a growing trend toward bridging the gap between molecular and bench research with clinical application in attempt to change the way surgeons approach patients and improve outcomes

conclusion

As the field of colon and rectal surgery continues to evolve as a specialty, emphasis on optimization of outcomes through pre-vention and early identification, and treatment of complications

is imperative As many complications are a result of multiple dif-ferent components, sometimes all working in concert to lead to untoward results, surgeons must also use a multifaceted approach

to ensure a successful perioperative course

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