Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_917_Библиотеки_им_академика_М_И_Перельмана.pdf
118
Table 9.3 Half-life and washout time of biologic treatments for IBD
Medication
Iniximab 8–9.5 40–47.5
Adalimumab 14 70
Certolizumab 14 70
Golimumab 9–15 45–75
Vedolizumab 25 125
Natalizumab 10–11 40–45
Ustekinumab 15(IV)
Tofacitinib 0.13 3
Half-lives and washout times for biologic therapies for IBD listed in days (IV intravenous, SQ
subcutaneous)
Half-life (d)
45.6 (SQ)
S. Eisenstein and A. L. Grucela
Washout (d)
75 (IV)
228 (SQ)
multiple biologics likely have the most severe disease. This needs to be taken into
consideration when planning surgery, and these patients should be treated as though
they have more severe illness than they may exhibit. A common approach to patients
on biologics is to wait until they are at the nadir of their dose, usually around the
time they are about to receive their next dose, delay that dose, perform their surgery,
and restart medication if medically necessary several weeks after surgery. It should
be remembered that these patients still have active therapy in their system, and the
only true way to ensure there is no drug present is to allow for a full washout which
is equivalent to ve half-lives of the medication (Table9.3).
Ideally, chemotherapy should be allowed to wash out of the patient’s system
prior to undergoing elective colorectal procedures. Chemotherapy can impair wound
healing, cause myelosuppression, impair immune responses, and lead to a variety of
other different issues which can increase the risk of postoperative complications.
When feasible, it is best to wait at least 6weeks after any dose of chemotherapy to
allow for washout. This is particularly true of bevacizumab, a monoclonal antibody
against vascular endothelial growth factor (VEGF), which impairs angiogenesis.
These patients are at a signicant risk of postoperative bleeding. Waiting for surgery
is not always feasible, and in the acute setting, patients undergoing chemotherapy
sometimes require urgent surgical intervention. When this occurs, it is always
important to take the chemotherapy into consideration when planning the type of
surgery and consider smaller, more temporizing procedures knowing that signicant intervention may lead to signicant complication.
Smokers
Smoking is a well-documented risk factor for complications after colon and rectal
surgery. Smoking has shown to contribute to increased risk of VTE, wound infection, anastomotic dehiscence, and hernia formation [23–25]. The effects of smoking
on the airway are also extensive. Carbon monoxide has deleterious effects on the
cardiovascular system and can persist for several hours after inhalation. Airway
sensitivity is increased, and these effects last 2–10days after inhalation. Mucus
secretion is also altered, and these effects can last for many weeks [26]. Smoking
cessation should be instituted at least 4 weeks prior to surgery, and it has been
9 Checklist forPatients andOR Team inPreparation forLaparoscopic Colorectal…
119
shown that there is increasing benet for every week beyond 4 that the patient is
able to stop smoking [23]. However, for those who have quit smoking for less than
4weeks, the alteration of mucus secretion may lead to greater risk of respiratory
complications from general anesthesia, and ideally it is best to wait until mucus
secretion and cilliation returns to its normal state [26].
One should consider canceling elective surgery in patients who are actively
smoking, and any patient who actively smokes and presents for surgery should be
counseled on smoking cessation techniques. The surgeon should seek help from the
patient’s primary care physician as they will often have a greater depth of experience in assisting the patients to adequate cessation. Several aides have also been
used in promoting smoking cessation. These include varenicline, bupropion, and
nicotine replacement. In a randomized controlled trial, varenicline demonstrated a
3.6-fold increase in smoking cessation compared to placebo, while bupropion and
nicotine replacement demonstrated a two-fold increase [27].
These techniques for smoking cessation are often not effective, and so many
surgeons will test their patient’s blood, urine, or saliva for nicotine or the by-product
of nicotine metabolism cotinine. Nicotine will only stay positive on a blood test for
several days after consumption, whereas cotinine may remain positive for several
weeks and is therefore a better test of long-term cessation than nicotine testing
alone. It should be noted that patients taking nicotine replacement will also test
positive for nicotine and cotinine, and so this should be taken into consideration
when counseling patients on their optimal cessation technique.
Malnutrition
It is also critical to ensure your patient’s nutritional status is optimized prior to
undergoing major abdominal surgery. Nutrition can be measured in many different
ways, whether its body mass index (BMI), weight loss, or hypoalbuminemia. It is
important to take all of these into consideration when evaluating a patient for surgery, but the single best test is likely hypoalbuminemia, which has been shown to be
the best predictor of most surgical complications as well as length of stay and overall complication rates when compared to weight loss and BMI in patients with
colorectal cancer [28]. Malnutrition has been shown to increase the risk of almost
every potential complication, from a variety of infectious and septic conditions, to
VTE and DVT, to anesthesia-related complications, as poor nutrition impairs every
major organ system, leaving patients open to postoperative dysfunction.
Improving upon patient nutrition prior to surgical intervention is necessary to
minimize the risk of complications. Patients who are at risk for malnutrition should
be assessed prior to surgery with an albumin and prealbumin levels. It should be
remembered that albumin is a better marker of chronic nutrition with a half-life of
20–22days, while prealbumin has a half-life of 2–4days and is a better gauge of the
direction a patient’s nutrition is trending. If a patient is determined to be malnourished, then intervention should be considered. Intervention should be chosen based
on the factors which led to the patient’s malnutrition as well as the acuity of the
problem and the timing of surgical intervention. Generally those who are in a catabolic condition should take in between 1.5 and 1.8g of protein per Kg of body
120
S. Eisenstein and A. L. Grucela
weight per day [29]. Vitamin D supplementation can also help increase muscle mass
and should also be considered [29].
Standard dietary supplementation with high-quality protein supplements (>30g
protein/serving) can be helpful, particularly if there is only mild malnutrition. Total
parenteral nutrition (TPN) should be considered in patients who are unable to take
enteral nutrition. These patients are at higher risk of line-related complications, but
this risk is trivial in comparison with those complications that the patient may
encounter due to their malnutrition. Enteral nutrition (EN) consists of elemental or
semi-elemental feeds delivered to the gut which recently has been shown to be the
preferred approach when possible. These data have been borne out in the IBD community where historically patients underwent prolonged usage of TPN for malabsorption and short gut. While studies have shown both TPN and EN are effective at
decreasing the risk of surgical complications compared to standard dietary intervention, EN has been shown to be superior to TPN with a number needed to treat of 2 to
prevent surgical complications [30]. One downside of EN, however, is that the enteral
feeds tend to be foul tasting and difcult to ingest, requiring prolonged placement of
a nasogastric tube for up to 4weeks prior to surgery. TPN tends to be easier to administer, and thus, when given the options, patients will often prefer TPN.
Preoperative immunonutrition is also a useful adjunct in colon and rectal surgery.
It is well documented that surgery leads to a state of relative immune suppression in
the perioperative period. Immunonutrition usually consists of supplements taken for
a week prior to surgery consisting of some combination of arginine, glutamine,
branched-chain amino acids, omega-3 fatty acids, and nucleotides. These are
designed to target mucosal barrier function, cellular defense, and local and systemic
inammation [31]. A large meta-analysis of immunonutrition showed that while it
does not improve mortality, it does decrease the risk of overall complication and
infectious complications and shortened hospital stay. The caveat to these data is that
when substratied to industry-sponsored vs nonsponsored trials, only the industry
sponsored trials demonstrated these benets [32].
Obesity
Obesity has been shown to increase the risk of almost every type of surgical complication in the colon and rectal surgery patient [33]. Having a plan in place for mitigating the risks of obesity is critical in ensuring optimal patient outcomes. The
extremely obese should not be considered for elective surgery without undergoing
some manner of weight loss program. This may ultimately include the consideration
of bariatric surgery prior to elective colorectal procedures in an attempt to optimize
the patient. There are also newer endoluminal approaches to weight loss which
carry a lower risk of complications while still achieving modest improvements in
both weight loss and correcting the various comorbidities associated with obesity
[34]. Morbidly obese patients who can delay their colorectal procedure should be
referred to a surgical weight loss team to undergo evaluation.
Many patients will not be able to undergo this long course of evaluation and
treatment prior to their surgical intervention. A very low calorie liquid diet has been
shown to decrease fat and in particular visceral fat in the preoperative period [35,
9 Checklist forPatients andOR Team inPreparation forLaparoscopic Colorectal…
121
36]. By decreasing visceral fat, specically a surgeon can gain length and reach of
bowel. This diet can be particularly helpful in procedures such as low anterior resections and ileal pouch-anal anastomosis where bowel length is crucial. Very low calorie liquid diets usually have the patient consume nutritional shakes that make up less
than 800kcal/day for 1–4weeks. The amount of fat loss correlates to the time the
patient consumes this diet, and it should be done under the direction of a medical or
surgical weight loss specialist to ensure that the patients are consuming the appropriate macronutrients.
For those patients who must undergo surgery prior to weight loss, it is important
to understand the risks obesity imparts upon the colon and rectal surgery patient.
Hernia rates and wound complications are signicantly increased in these patients.
A minimally invasive approach and off-midline extraction may be helpful in minimizing these wound complications [33, 37]. Surgical site infections are also
increased in this population [33]. This may mean that an otherwise uneventful case
may still benet from anastomotic diversion in an attempt to minimize the risk of a
leak. These patients may also benet from drains in their subcutaneous tissues to
minimize the risk of infected fat necrosis. Obese patients are also at an increased
risk of respiratory and cardiovascular complications from anesthesia [33]. Therefore,
it is helpful to include the anesthesia team in your surgical planning and consider
prolonged postoperative monitoring for adverse events.
Renal Impairment
Chronic dialysis has been demonstrated to increase the risk of major complications
from elective colorectal procedures by at least 2.5-fold and mortality by seven-fold
[38]. These patients are particularly difcult to manage postoperatively especially
with regard to managing their uid balance. If these patients present with sepsis, it
can be quite difcult to ensure that they maintain the appropriate intravascular volume to support their circulatory system without putting the patient into pulmonary
edema. These patients are at a signicantly increased risk of both bleeding and VTE
[38]. And because of this, it is crucial to carefully manage any postoperative anticoagulation. Patients on dialysis should be managed in conjunction with a nephrologist who should see the patient prior to surgery to ensure that they are optimized.
Dialysis should be optimally timed for surgery. It has been shown that an interval of
less than 7hours between dialysis and surgery can lead to postoperative hypotension due to the depleted intravascular state with which these patients undergo surgery [39]. Therefore, it is likely best to dialyze a patient the day prior to surgery to
ensure they are undergoing their procedure at euvolemia.
Chronic kidney disease (CKD) not on dialysis also imparts an increased risk of
perioperative complications. CKD patients undergoing colorectal resections were
more likely to develop cardiovascular complications postoperatively and have a
greater than two-fold risk of 30-day mortality [40]. These patients have the potential
to be more dysregulated than the dialysis patients depending on their degree of renal
impairment. Uremia can lead to a pro-inammatory state which can lead to an
increased risk of atherosclerotic complications as well as infections and bleeding
problems. These patients are also often malnourished and volume overloaded, their
122
S. Eisenstein and A. L. Grucela
electrolytes are unbalanced, and they have relative immune suppression. These
patients are also often anemic and may benet from preoperative erythropoietin.
When possible their renal function should be optimized as much as possible, and
electrolytes should be checked immediately prior to surgery and frequently throughout their procedures.
Preoperative Stoma Marking
Preoperative stoma marking should be arranged for all patients undergoing colon
and rectal surgery who may require a stoma at the time of their procedure. A frank
conversation about the risks of colostomy or ileostomy is absolutely necessary
before attempting bowel surgery. Patients should be aware of the likelihood of this
outcome prior to undergoing surgery.
The surgeon may elect to perform their own marking, taking into consideration
where the patient’s belt line may fall and then evaluating the abdominal contours.
The patient should be evaluated in a variety of positions including sitting and supine.
Creases, folds, and surgical scars should be avoided as they are a common site of
leakage. Stoma marking should occur medial to the lateral border of the rectus
abdominis muscle which can be easily palpated by having the patient sit up part way
from the supine position, putting this muscle on tension. Oftentimes, it is necessary
to mark multiple locations, either bilaterally or in the upper and lower abdomen
depending on the patient’s habitus and the potential for different types of stomas
which could be created at the time of surgery.
It is often much more benecial for the patient to be marked by an enterostomal
therapist (EST) or a wound, ostomy, and continence nurse (WOCN). These specialists not only mark the patient prior to surgery, but they help educate the patient on
what life with a stoma may be like. They introduce the patients to the equipment and
help them gain a familiarity. Oftentimes these nurses will see the patients in the
hospital and continue their education prior to and post discharge. For more details
on stomas, please refer to Chap. 36 on optimizing stoma function and quality of life.
Preoperative Patient Education
Patient education is a critical part of the enhanced recovery process and of managing expectations of what they will experience during their postop period/hospital
stay and at home. Patient education materials should be distributed including the
preoperative plan and preparation and what to expect. See Fig.9.1 for an example.
These materials have been demonstrated to help assuage patient’s fears of the
unknown and have been demonstrated to decrease length of hospital stay [41].
Current enhanced recovery and surgical site infection (SSI) prevention protocol
bundles may include aspects to improve return of bowel function, improved length
of stay, and decrease wound infection rates. These are often institution-specic but
9 Checklist forPatients andOR Team inPreparation forLaparoscopic Colorectal…
123
Fig. 9.1 NYU Langone Medical Center colon pathway. (Used with permission. Copyright ©
NYU Langone Health)
124
S. Eisenstein and A. L. Grucela
Fig. 9.1 (continued)
9 Checklist forPatients andOR Team inPreparation forLaparoscopic Colorectal…
125
Fig. 9.1 (continued)
126
S. Eisenstein and A. L. Grucela
Fig. 9.1 (continued)
may include mechanical and antibiotic bowel preparation, carbohydrate loading/
drinks, chlorhexidine shower, or wipes. For more specic recommendations, please
refer to the chapters on enhanced recovery protocols (Chap. 7) in colorectal surgery
and on bowel preparation (Chap. 8) in colorectal surgery.
9 Checklist forPatients andOR Team inPreparation forLaparoscopic Colorectal…
127
Operative Setup, Pitfalls, andTroubleshooting
Local, Regional, andEpidural Anesthesia
Multimodal analgesia is an important part of postoperative recovery after laparoscopic colon and rectal surgery as minimizing the use of narcotics aids in intestinal
recovery. Patients should be evaluated prior to surgery for any effective adjunct to
their postoperative pain control which may help minimize the postoperative use of
narcotics and thus facilitate a quicker return of bowel function.
Transversus abdominis plane (TAP) blocks are a mainstay of perioperative
abdominal anesthesia. Local anesthetic is injected into the neurovascular plane
between the transversus abdominis and the internal oblique. This effectively blocks
T7-L1 innervation to the abdominal wall for up to the rst 24hours after surgery,
depending on the type of local anesthetic used. This can be done during laparoscopic surgery under direct visualization, or it can be done preoperatively using
ultrasound guidance by the surgeon or anesthesiologist. Studies comparing TAP
block to local wound inltration have demonstrated similar visual analog scale
(VAS) pain scores during the rst 24hours, but they have also demonstrated a signicant decrease in narcotic use during that same time period [42, 43], demonstrating that this can be a useful adjunct in aiding return of bowel function to expedite
postoperative recovery.
There is extensive evidence that thoracic epidural anesthesia (TEA) decreases
postoperative pain and narcotic use, expediting the recovery of bowel function in
open surgery. The evidence for TEA usage in laparoscopic surgery is less conclusive. Several studies have examined the impact of epidural anesthesia on postoperative outcomes from laparoscopic colectomy and proctectomy. Most have shown that
TEA leads to longer hospital stay, increased costs, and no decrease in postoperative
ileus [44–46]. Pain score improvement versus conventional postoperative narcotic
analgesia varies but generally is not better [44–46]. These studies do have several
problems, however, as there is some heterogeneity as to which patients receive epidural narcotics as opposed to just local anesthetic as well as including a diverse
group of surgeries. Many of the studies are also retrospective, and therefore the
TEA patients tend to be the ones with more risk factors for postoperative complications. Patients being considered for laparoscopic procedures who have a high risk of
conversion based on preoperative factors to open should be considered for TEA as
this can be removed in the early postoperative period if the surgery stays minimally
invasive.
Intravenous lidocaine infusions have been used as an adjunct both during anesthesia and postoperatively in the recovery and on the oor. Preliminary results of
multiple studies have shown less postoperative pain, less narcotic use with earlier
return of bowel function, and no adverse events [47, 48]. Patients need to be monitored, which can result in resistance in adaptation; however, cardiac complications
such as arrhythmias and other adverse effects are rare. With a sound, data-driven
protocol and team education, this can be easily employed.