Postoperative Work and Activity Restrictions After Abdominal Surgery: A Systematic Review.

OBJECTIVE: This systematic review aims to assess what is known about convalescence following abdominal surgery. Through a review of the basic science and clinical literature, we explored the effect of physical activity on the healing fascia and the optimal timing for postoperative activity. BACKGROUND: Abdominal surgery confers a 30% risk of incisional hernia development. To mitigate this, surgeons often impose postoperative activity restrictions. However, it is unclear whether this is effective or potentially harmful in preventing hernias. METHODS: We conducted 2 separate systematic reviews using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The first assessed available basic science literature on fascial healing. The second assessed available clinical literature on activity after abdominal surgery. RESULTS: Seven articles met inclusion criteria for the basic science review and 22 for the clinical studies review. The basic science data demonstrated variability in maximal tensile strength and time for fascial healing, in part due to differences in layer of abdominal wall measured. Some animal studies indicated a positive effect of physical activity on the healing wound. Most clinical studies were qualitative, with only 3 randomized controlled trials on this topic. Variability was reported on clinician recommendations, time to return to activity, and factors that influence return to activity. Interventions designed to shorten convalescence demonstrated improvements only in patient-reported symptoms. None reported an association between activity and complications, such as incisional hernia. CONCLUSIONS: This systematic review identified gaps in our understanding of what is best for patients recovering from abdominal surgery. Randomized controlled trials are crucial in safely optimizing the recovery period.

A population-based study comparing laparoscopic and robotic outcomes in colorectal surgery.

BACKGROUND: Current data addressing the role of robotic surgery for the management of colorectal disease are primarily from single-institution and case-matched comparative studies as well as administrative database analyses. The purpose of this study was to compare minimally invasive surgery outcomes using a large regional protocol-driven database devoted to surgical quality, improvement in patient outcomes, and cost-effectiveness. METHODS: This is a retrospective cohort study from the prospectively collected Michigan Surgical Quality Collaborative registry designed to compare outcomes of patients who underwent elective laparoscopic, hand-assisted laparoscopic, and robotic colon and rectal operations between July 1, 2012 and October 7, 2014. We adjusted for differences in baseline covariates between cases with different surgical approaches using propensity score quintiles modeled on patient demographics, general health factors, diagnosis, and preoperative co-morbidities. The primary outcomes were conversion rates and hospital length of stay. Secondary outcomes included operative time, and postoperative morbidity and mortality. RESULTS: A total of 2735 minimally invasive colorectal operations met inclusion criteria. Conversion rates were lower with robotic as compared to laparoscopic operations, and this was statistically significant for rectal resections (colon 9.0 vs. 16.9%, p < 0.06; rectum 7.8 vs. 21.2%, p < 0.001). The adjusted length of stay for robotic colon operations (4.00 days, 95% CI 3.63-4.40) was significantly shorter compared to laparoscopic (4.41 days, 95% CI 4.17-4.66; p = 0.04) and hand-assisted laparoscopic cases (4.44 days, 95% CI 4.13-4.78; p = 0.008). There were no significant differences in overall postoperative complications among groups. CONCLUSIONS: When compared to conventional laparoscopy, the robotic platform is associated with significantly fewer conversions to open for rectal operations, and significantly shorter length of hospital stay for colon operations, without increasing overall postoperative morbidity. These findings and the recent upgrades in minimally invasive technology warrant continued evaluation of the role of the robotic platform in colorectal surgery.

Primum non nocere: A therapeutic imperative for modern wound care.

This new paradigm revolves around meticulous wound bed preparation to allow the wound to proceed to endogenous healing or to set the stage for successful wound closure with autologous tissue.

Evolution and advances in laparoscopic ventral and incisional hernia repair.

Primary ventral hernias and ventral incisional hernias have been a challenge for surgeons throughout the ages. In the current era, incisional hernias have increased in prevalence due to the very high number of laparotomies performed in the 20(th) century. Even though minimally invasive surgery and hernia repair have evolved rapidly, general surgeons have yet to develop the ideal, standardized method that adequately decreases common postoperative complications, such as wound failure, hernia recurrence and pain. The evolution of laparoscopy and ventral hernia repair will be reviewed, from the rectoscopy of the 4(th) century to the advent of laparoscopy, from suture repair to the evolution of mesh reinforcement. The nuances of minimally invasive ventral and incisional hernia repair will be summarized, from preoperative considerations to variations in intraoperative practice. New techniques have become increasingly popular, such as primary defect closure, retrorectus mesh placement, and concomitant component separation. The advent of robotics has made some of these repairs more feasible, but only time and well-designed clinical studies will tell if this will be a durable modality for ventral and incisional hernia repair.

Nonsteroidal Anti-inflammatory Drugs: Do They Increase the Risk of Anastomotic Leaks Following Colorectal Operations?

BACKGROUND: Nonsteroidal anti-inflammatory drugs have become an important component of narcotic-sparing postoperative pain management protocols. However, conflicting evidence exists regarding the adverse association of nonsteroidal anti-inflammatory drug use with intestinal anastomotic healing in colorectal surgery. OBJECTIVE: This study compares patients receiving nonsteroidal anti-inflammatory drugs on postoperative day 1 with patients who did not receive nonsteroidal anti-inflammatory drugs with regard to the occurrence of anastomotic leaks. DESIGN: This is a retrospective study from a protocol-driven prospectively collected statewide database. A propensity score model was used to adjust for differences between the groups in patient demographics, characteristics, comorbidities, and laboratory values. SETTINGS: The multicenter data set used in this analysis represents a variety of academic and community hospitals within the state of Michigan from July 2012 through February 2014. PATIENTS: Nonpregnant patients over the age of 18 who underwent colon and rectal surgery with bowel anastomosis were selected. MAIN OUTCOME MEASURES: Occurrence of anastomotic leak, composite surgical site infection, sepsis, and death within 30 days of surgery were the primary outcomes measured. RESULTS: A total of 4360 patients met inclusion criteria, of which 1297 (29.7%) received nonsteroidal anti-inflammatory drugs and 3063 (70.3%) did not receive nonsteroidal anti-inflammatory drugs. There was no statistically significant difference between the 2 groups in the proportion of cases with anastomotic leak (OR, 1.33; CI, 0.86-2.05; p = 0.20), composite surgical site infection (OR, 1.26; CI, 0.96-1.66; p = 0.09), or death within 30 days (OR, 0.58; CI, 0.28-1.19; p = 0.14). There was a significantly greater risk of sepsis for patients given nonsteroidal anti-inflammatory drugs than for those patients not given nonsteroidal anti-inflammatory drugs (OR, 1.47; CI, 1.05-2.06; p = 0.03). LIMITATIONS: This is a nonrandomized study performed retrospectively, and it is based on data collected only within a subset of hospitals in the state of Michigan. CONCLUSIONS: No statistically significant increase in the proportion of patients with anastomotic leak was observed when prescribing nonsteroidal anti-inflammatory drugs for analgesia in the early postoperative period for patients undergoing elective colorectal surgery. Unexpectedly, there was an increased risk of sepsis that warrants further investigation (see video, Supplemental Digital Content 1, http://links.lww.com/DCR/A192, for a synopsis of this study).

Postoperative hyperglycemia and adverse outcomes in patients undergoing colorectal surgery: results from the Michigan surgical quality collaborative database.

PURPOSE: Our objective was to assess the relationship between high blood glucose levels (BG) in the early postoperative period and the incidence of surgical site infections (SSIs), sepsis, and death following colorectal operations. METHODS: The Michigan Surgical Quality Collaborative database was queried for colorectal operations from July 2012 to December 2013. Normoglycemic (BG < 180 mg/dL) and hyperglycemic (BG ≥ 180 mg/dL) groups were defined by using the highest BG within the first 72 h postoperatively. Outcomes of interest included the incidence of superficial, deep, and organ/space SSIs, sepsis, and death within 30 days. Initial unadjusted analysis was followed by propensity score matching and multiple logistic regression modeling after adjusting for significant predictors. Separate analyses were performed for previously diagnosed diabetic and non-diabetic patients. RESULTS: A total of 5145 cases met inclusion criteria, of which 1072 were diabetic. For diabetic patients, there was a marginally significant association between high BG and superficial SSI in the unadjusted analysis (OR = 1.75, p = 0.056), but not in the adjusted analysis (OR = 1.35, p = 0.39). There was no significant relationship between elevated BG and deep SSI, organ/space SSI, sepsis, or death among diabetic patients. For non-diabetic patients, there was a significant association between high BG and superficial SSI (OR = 1.53, p = 0.03), sepsis (OR = 1.61, p < 0.01), and death (OR = 2.26, p < 0.01), but not deep or organ/space SSI. CONCLUSIONS: Following colorectal operations, superficial SSI, sepsis, and death are associated with postoperative serum hyperglycemia in patients without diabetes, but not those with diabetes. Vigilant postoperative BG monitoring is critical for all patients undergoing colorectal surgery.

Is hepato-imino diacetic acid scan a better imaging modality than abdominal ultrasound for diagnosing acute cholecystitis?

BACKGROUND: The role of hepato-imino diacetic acid scan (HIDA) in the diagnosis of acute cholecystitis remains controversial when compared with the more commonly used abdominal ultrasound (AUS). METHODS: The diagnostic imaging workup of 1,217 patients who presented to the emergency department at a single hospital with acute abdominal pain and suspicion of acute cholecystitis was reviewed to calculate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of AUS and HIDA. RESULTS: In patients undergoing both imaging modalities, HIDA had significantly higher sensitivity (90.7% vs 64.0%, P < .001) and specificity (71.4% vs 58.4%, P = .005) than AUS for the diagnosis of acute cholecystitis. Additionally, PPV and NPV of HIDA (56.2% and 95.0%, respectively) were higher than PPV and NPV of AUS (38.4% and 80.0%, respectively) when both imaging modalities were used for the same patient. CONCLUSION: In adults with acute abdominal pain, HIDA significantly increases the accuracy of the correct diagnosis.

Contraction of abdominal wall muscles influences size and occurrence of incisional hernia.

BACKGROUND: Incisional hernias are a complication in 10% of all open abdominal operations and can result in substantial morbidity. The purpose of this study was to determine whether inhibiting abdominal muscle contraction influences incisional hernia formation during the fascial healing after laparotomy. We hypothesized that decreasing the deformation of the abdominal musculature would decrease the size or occurrence of an incisional hernia. METHODS: Using an established rat model for incisional hernia, a laparotomy through the linea alba was closed with 1 mid-incision, fast-absorbing suture. Three groups were compared: a sham group (sham; n = 6) received no laparotomy, and the saline hernia (SH; n = 6) and Botox hernia (BH; n = 6) groups were treated once with equal volumes of saline or botulinum toxin (Botox, Allergan) before the incomplete laparotomy closure. On postoperative day 14, the abdominal wall was examined for herniation and adhesions, and contractile forces were measured for abdominal wall muscles. RESULTS: No hernias developed in the sham rats. Rostral hernias developed in all SH and BH rats. Caudal hernias developed in all SH rats, but in only 50% of the BH rats. Rostral hernias in the BH group were 35% shorter and 43% narrower compared with those in the SH group (P < .05). The BH group had weaker abdominal muscles compared with the sham and SH groups (P < .05). CONCLUSION: In our rat model, partial paralysis of abdominal muscles decreases the number and size of incisional hernias. These results suggest that contractions of the abdominal wall muscle play a role in the pathophysiology of the formation of incisional hernias.

Early laparotomy wound failure as the mechanism for incisional hernia formation.

BACKGROUND: Incisional hernia is the most common complication of abdominal surgery leading to reoperation. In the United States, 200,000 incisional hernia repairs are performed annually, often with significant morbidity. Obesity is increasing the risk of laparotomy wound failure. METHODS: We used a validated animal model of incisional hernia formation. We intentionally induced laparotomy wound failure in otherwise normal adult, male Sprague-Dawley rats. Radio-opaque, metal surgical clips served as markers for the use of x-ray images to follow the progress of laparotomy wound failure. We confirmed radiographic findings of the time course for mechanical laparotomy wound failure by necropsy. RESULTS: Noninvasive radiographic imaging predicts early laparotomy wound failure and incisional hernia formation. We confirmed both transverse and craniocaudad migration of radio-opaque markers at necropsy after 28 d that was uniformly associated with the clinical development of incisional hernias. CONCLUSIONS: Early laparotomy wound failure is a primary mechanism for incisional hernia formation. A noninvasive radiographic method for studying laparotomy wound healing may help design clinical trials to prevent and treat this common general surgical complication.

Reversibility of abdominal wall atrophy and fibrosis after primary or mesh herniorrhaphy.

OBJECTIVE: To determine whether primary or mesh herniorrhaphy reverses abdominal wall atrophy and fibrosis associated with hernia formation. BACKGROUND: We previously demonstrated that hernia formation is associated with abdominal wall atrophy and fibrosis after 5 weeks in an animal model. METHODS: A rat model of chronic incisional hernia was used. Groups consisted of uninjured control (UC, n = 8), sham repair (SR, n = 8), unrepaired hernia (UR, n = 8), and 2 repair groups: primary repair (PR, n = 8) or tension-free polypropylene mesh repair (MR, n = 8) hernia repair on postoperative day (POD) 35. All rats were killed on POD 70. Intact abdominal wall strips were cut perpendicular to the wound for tensiometric analysis. Internal oblique muscles were harvested for fiber type and size determination. RESULTS: No hernia recurrences occurred after PR or MR. Unrepaired abdominal walls significantly demonstrated greater stiffness, increased breaking and tensile strengths, yield load and yield energy, a shift to increased type IIa muscle fibers than SR (15.9% vs 9.13%; P < 0.001), and smaller fiber cross-sectional area (CSA, 1792 vs 2669 µm(2); P < 0.001). PR failed to reverse any mechanical changes but partially restored type IIa fiber (12.9% vs 9.13% SR; P < 0.001 vs 15.9% UR; P < 0.01) and CSA (2354 vs 2669 µm(2) SR; P < 0.001 vs 1792 µm(2) UR; P < 0.001). Mesh-repaired abdominal walls demonstrated a trend toward an intermediate mechanical phenotype but fully restored type IIa muscle fiber (9.19% vs 9.13% SR; P > 0.05 vs 15.9% UR; P < 0.001) and nearly restored CSA (2530 vs 2669 µm(2) SR; P < 0.05 vs 1792 µm(2) UR; P < 0.001). CONCLUSIONS: Mesh herniorrhaphy more completely reverses atrophic abdominal wall changes than primary herniorrhaphy, despite failing to restore normal anatomic muscle position. Techniques for hernia repair and mesh design should take into account abdominal wall muscle length and tension relationships and total abdominal wall compliance.

Porcine incisional hernia model: Evaluation of biologically derived intact extracellular matrix repairs.

We compared fascial wounds repaired with non-cross-linked intact porcine-derived acellular dermal matrix versus primary closure in a large-animal hernia model. Incisional hernias were created in Yucatan pigs and repaired after 3 weeks via open technique with suture-only primary closure or intraperitoneally placed porcine-derived acellular dermal matrix. Progressive changes in mechanical and biological properties of porcine-derived acellular dermal matrix and repair sites were assessed. Porcine-derived acellular dermal matrix-repaired hernias of additional animals were evaluated 2 and 4 weeks post incision to assess porcine-derived acellular dermal matrix regenerative potential and biomechanical changes. Hernias repaired with primary closure showed substantially more scarring and bone hyperplasia along the incision line. Mechanical remodeling of porcine-derived acellular dermal matrix was noted over time. Porcine-derived acellular dermal matrix elastic modulus and ultimate tensile stress were similar to fascia at 6 weeks. The biology of porcine-derived acellular dermal matrix-reinforced animals was more similar to native abdominal wall versus that with primary closure. In this study, porcine-derived acellular dermal matrix-reinforced repairs provided more complete wound healing response compared with primary closure.

Loss of mechanical strain impairs abdominal wall fibroblast proliferation, orientation, and collagen contraction function.

BACKGROUND: Laparotomy wound load forces are reduced when dehiscence and incisional hernia formation occur. The purpose of this study was to determine the effects of strain loss on abdominal fascial fibroblast proliferation, orientation, and collagen compaction function. METHODS: Cultured rat linea alba fibroblasts were subjected to continuous cyclic strain (CS), CS interrupted at 24 or 48 hours followed by culture at rest (IS-24 and IS-48) or were cultured without mechanical strain (NS). Cell number was measured and images analyzed for cell orientation. Fibroblasts from these groups were seeded onto the surface of (FPCL-S) or mixed into (FPCL-M) a collagen gel matrix and gel area was measured over time. RESULTS: Continuous strain stimulated proliferation when compared with the nonstrained cells. The loss of strain (IS) delayed proliferation compared with CS throughout (P < .05). CS fibroblasts aligned perpendicular to the direction of strain within 12 hours. Within 12 hours of strain loss, IS-48 fibroblasts became significantly less aligned (P < .0001), and seemed similar to the randomly organized NS fibroblasts 48 hours after strain removal. The CS and IS-24 groups demonstrated faster and greater overall FPCL-M compaction than both the IS-48 and NS groups (P < .0002). The CS group contracted the gel faster than the NS group in FPCL-S (P = .029). CONCLUSION: Mechanical strain rapidly induces a proliferative, morphologic, and functional response in abdominal wall fibroblasts that is dependent on the continued presence of the strain signal and quickly lost when the load force is removed. The loss of wound edge tension that occurs during laparotomy wound separation and hernia formation may contribute to impaired wound healing through loss of a key stimulatory mechanical signal with important implications for abdominal wall reconstruction.

Usefulness of the twinkling artifact in identifying implanted mesh after inguinal hernia repair.

OBJECTIVES: Implanted mesh for inguinal hernia repair is often difficult to visualize with gray scale sonography and may present without the knowledge of the sonographer. We sought to evaluate the utility of the twinkling artifact produced by inguinal mesh to assist in mesh identification. METHODS: Two reviewers evaluated focused sonographic examinations of 44 inguinal regions, 24 of which had implanted inguinal mesh. The sonographic examinations consisted of static gray scale and color Doppler images with both linear and curvilinear array transducers. The presence of the twinkling artifact and visibility of the mesh were graded on a 4-point visibility scale. RESULTS: Inguinal mesh was not easily identified on gray scale imaging using either the curvilinear array (P = .5) or linear array (P = .5) transducer. The mesh was definitely seen in 3 of 24 inguinal regions using the linear array transducer and 2 of 24 inguinal regions using the curvilinear array transducer. In 79% of inguinal regions with mesh, the twinkling artifact was produced with the curvilinear array transducer only. The artifact was not elicited when using the linear array transducer. With the use of the curvilinear array transducer and the presence of the twinkling artifact, there was a significant chance of correctly identifying the presence of mesh (P < .005) in the entire study group. CONCLUSIONS: Standard gray scale imaging alone is not reliable when identifying inguinal mesh. The twinkling artifact was present in 79% of inguinal regions with mesh when evaluated with a low-frequency curvilinear array transducer.

The use of amnion-derived cellular cytokine solution to improve healing in acute and chronic wound models.

OBJECTIVE: Growth factors demonstrate mixed results improving wound healing. Amnion-derived multipotent cells release physiologic levels of growth factors and tissue inhibitors of metalloproteinases. This solution was tested in models of acute and chronic wound healing. METHODS: Acute model: Sprague-Dawley rats underwent laparotomy incisions. The midline fascia was primed with phosphate-buffered saline, unconditioned media, or amnion-derived cellular cytokine suspension prior to incision. Breaking strength of laparotomy wounds was tested with an Instron tensiometer. Incisional hernia formation was measured after 28 days. Chronic model: Chronic, infected granulating wounds were produced in rats by excising full thickness burn eschars inoculated with Escherica coli. Granulating wounds were treated with unconditioned media or amnion-derived cellular cytokine suspension. Treatments were applied either on day 0 and day 7 or day 0 and then every other day. Wounds were traced every 72 hours and biopsied for quantitative bacteriology. RESULTS: Acute model: Priming with amnion-derived cellular cytokine suspension increased the breaking strength of laparotomy incisions in comparison with phosphate-buffered saline or unconditioned media (P < .05). Acute wound failure and incisional hernia formation was 100% in the phosphate-buffered saline and unconditioned media groups and 18% in the amnion-derived cellular cytokine suspension-treated group (P <.05). Chronic model: The rate of wound closure was accelerated in amnion-derived cellular cytokine suspension-treated chronic wounds (P < .05). Multidosing improved the effect. CONCLUSIONS: A physiologic solution of cytokines and tissue inhibitors of metalloproteinases improves healing in models of acute and chronic wounds. Such a cocktail can be produced from amnion-derived multipotent progenitor cells.

Abdominal wall hernia mesh repair: sonography of mesh and common complications.

OBJECTIVE: The purposes of this study were (1) to review the sonographic in vitro and in vivo appearances of mesh for surgical repair of abdominal wall hernias, (2) to describe sonographic techniques and discuss the limitations of sonography in evaluation of mesh hernia repair, and (3) to illustrate common complications after mesh repair shown with sonography. METHODS: We identified interesting cases from the musculoskeletal sonographic database as well as from the teaching files of the authors, with surgical or other cross-sectional imaging corroboration. RESULTS: A compilation of the sonographic appearances of mesh used for anterior abdominal wall and inguinal hernia repair and complications diagnosable by sonography is presented. CONCLUSIONS: Sonography can be effective for evaluation of mesh and complications after mesh repair of anterior abdominal wall and inguinal hernias.

The biology of hernia formation.

Abdominal wall hernias occur when tissue structure and function are lost at the load-bearing muscle, tendon, and fascial layer. The fundamental biologic mechanisms are primary fascial pathology or surgical wound failure. In both cases, cellular and extracellular molecular matrix defects occur. Primary abdominal wall hernias have been associated with extracellular matrix diseases. Incisional hernias and recurrent inguinal hernias more often involve a combination of technical and biologic limitations. Defects in wound healing and extracellular matrix synthesis contribute to the high incidence of incisional hernia formation following laparotomy.

Amnion-derived multipotent progenitor cells increase gain of incisional breaking strength and decrease incidence and severity of acute wound failure.

OBJECTIVE: Acute wound failure is a common complication following surgical procedures and trauma. Laparotomy wound failure leads to abdominal dehiscence and incisional hernia formation. Delayed recovery of wound-breaking strength is one mechanism for laparotomy wound failure. Early fascial wounds are relatively acellular, and there is a delay in the appearance of acute wound growth factors and cytokines. The objective of this study was to accelerate and improve laparotomy wound healing using amnion-derived multipotent cells (AMPs). AMPs' nonimmunogenic phenotype and relative abundance support its role as a cell therapy. METHODS: AMPs were injected into the load-bearing layer of rat abdominal walls prior to laparotomy, and cell viability was confirmed. Wound mechanical properties were measured over 28 days. The incidence and severity of laparotomy wound failure was measured in an incisional hernia model. RESULTS: AMP cells were viable in laparotomy wounds for at least 28 days and did not migrate to other tissues. Laparotomy wound-breaking strength was increased by postoperative day 7 following AMP therapy. AMP therapy reduced the incidence of hernia formation and the size of hernia defects. Histology suggested stimulated wound fibroplasia and angiogenesis. CONCLUSIONS: AMP cell therapy reduces the incidence of laparotomy wound failure by accelerating the recovery of wound-breaking strength. This results in fewer incisional hernias and smaller hernia defects.

Characteristic locations of inguinal region and anterior abdominal wall hernias: sonographic appearances and identification of clinical pitfalls.

OBJECTIVE: The purpose of this article is to show the typical locations of anterior abdominal wall and inguinal region hernias and to illustrate their sonographic appearances and describe pitfalls in clinical diagnosis of hernias that may be resolved with sonography. CONCLUSION: Awareness of the expected locations of anterior abdominal wall hernias and potential clinical pitfalls allows an accurate diagnosis of a hernia and helps in differentiating a hernia from other abnormalities.