Preservation of deep epigastric perforators during anterior component separation technique (ACST) results in equivalent wound complications compared to transversus abdominis release (TAR)

PURPOSE

The use of component separation results in myofascial release and increased rates of fascial closure in abdominal wall reconstruction(AWR). These complex dissections have been associated with increased rates of wound complications with anterior component separation having the greatest wound morbidity. The aim of this paper was to compare the wound complication rate between perforator sparing anterior component separation(PS-ACST) and transversus abdominus release(TAR).

METHODS

Patients were identified from a prospective, single institution hernia center database who underwent PS-ACST and TAR from 2015 to 2021. The primary outcome was wound complication rate. Standard statistical methods were used, univariate analysis and multivariable logistic regression were performed.

RESULTS

A total of 172 patients met criteria, 39 had PS-ACST and 133 had TAR performed. The PS-ACST and TAR groups were similar in terms of diabetes (15.4% vs 28.6%, p = 0.097), but the PS-ACST group had a greater percentage of smokers (46.2% vs 14.3%, p < 0.001). The PS-ACST group had a larger hernia defect size (375.2 ± 156.7 vs 234.4 ± 126.9cm2, p < 0.001) and more patients who underwent preoperative Botulinum toxin A (BTA) injections (43.6% vs 6.0%, p < 0.001). The overall wound complication rate was not significantly different (23.1% vs 36.1%, p = 0.129) nor was the mesh infection rate (0% vs 1.6%, p = 0.438). Using logistic regression, none of the factors that were significantly different in the univariate analysis were associated with wound complication rate (all p > 0.05).

CONCLUSION

PS-ACST and TAR are comparable in terms of wound complication rates. PS-ACST can be used for large hernia defects and promote fascial closure with low overall wound morbidity and perioperative complications.

OC-036 DEVELOPMENT OF NOVEL IMAGE-BASED DEEP LEARNING MODELS (DLMS) TO PREDICT OUTCOMES IN ABDOMINAL WALL RECONSTRUCTION (AWR) WITH IMBALANCED DATA SETS

Aim

The development of DLMs with imbalanced datasets represents a major challenge in the fields of artificial intelligence and surgery. The aim of this study was to develop and compare DLMs that predict mesh infection and pulmonary failure following AWR.

Methods

A prospectively maintained institutional database was used to identify AWR patients with preoperative CT scans. Standardized axial cuts of CT scans were rendered to DLMs. Conventional DLMs (CDLM) were developed two-class training system (i.e., learns negative and positive outcomes). CDLMs were compared to DLMs that were developed using a Generative Adversarial Network Anomaly (GANomaly) framework, which utilizes image augmentation and anomaly detection. The primary outcomes were receiver operating characteristic (ROC) values for predicting mesh infection and pulmonary failure.

Results

CT scans from 510 patients were utilized (10,004 images). Mesh infection and pulmonary failure occurred in 3.7% and 5.6% of patients, respectively. The CDLMs were less effective than GANomaly for predicting mesh infection (ROC 0.61 vs 0.73, p&lt;0.01) and pulmonary failure (ROC 0.59 vs 0.70, p&lt;0.01). Although the CDLMs had higher accuracies/specificities for predicting mesh infection (0.93 vs 0.78, p&lt;0.01/0.96 vs 0.78, p&lt;0.01) and pulmonary failure (0.88 vs 0.68, p&lt;0.01/0.92 vs 0.67, p&lt;0.01), they were substantially compromised by decreased model sensitivity (0.25 vs 0.68, p&lt;0.01/ 0.27 vs 0.73, p&lt;0.01).

Conclusions

Compared to CDLMs, GANomaly DLMs showed improved performance on imbalanced datasets, predominantly by increasing model sensitivity. Understanding patients who are at-risk for postoperative complications can improve risk stratification.

OC-011 PREOPERATIVE BOTULINUM TOXIN A INJECTION CAN ACHIEVE SIMILAR OUTCOMES AS COMPONENT SEPARATION TECHNIQUES IN COMPLEX ABDOMINAL WALL RECONSTRUCTION WITH DECREASED MORBIDITY– A PROPENSITY-SCORED MATCHED STUDY

Aims

CST have been effective in closing large defects but at the sacrifice of fascia and muscle and often increasing complication rates. Preoperative BTA has emerged as an adjunct to aid in fascial closure. Little data exist comparing pre-operative BTA versus CST, and our aim was to do so in a matched study.

Materials & Methods

A 3:1 propensity matched study of patients from a single institution hernia database undergoing AWR from 2016 to 2021 with BTA versus CST was performed based on BMI, defect width, hernia volume, and CDC wound classification. Demographics, operative characteristics, and outcomes were evaluated.

Results

35 BTA vs 105 CST matched patients were analyzed. Hernia defects and volume were large for both the CST and BTA groups (mean size:286.2+179.9cm2vs289.7+162.4cm2;p=0.73) (mean volume:1498.3+2043.4cm3vs2914.7+6539.4cm3;p=0.35). CDC wound classifications were equivalent (CDC3 and 4–39.1%vs40.0%;p=0.97). CST was more frequently performed in European Hernia Society M1 hernias (21% vs 2.9%;p=0.01). The BTA group had fewer surgical site occurrences (SSO) (32.4%vs11.4%;p=0.02) and surgical site infections (SSI) (11.7%vs0%;p=0.04). There was no difference in fascial closure (90.5%vs100%;p=0.11)) or recurrence (12.4%vs2.9%;p=0.10) with similar median follow-up (22.8+29.7vs 9.8+12.7months;p=0.13). In multivariate analysis, BTA was associated with lower rates of SSO (OR=5.3; 95% CI [1.4–34.4]).

Conclusion

There was no difference in fascial closure rates or in hernia recurrence between the two groups. Pre-operative BTA can thereby achieve similar outcomes as CST while concurrently decreasing the frequency of SSO. This similarity in outcomes is upheld when comparing BTA to both ACST and PCST separately.

OC-034 EVIDENCE-BASED CHANGES IN PERI-OPERATIVE PATIENT CARE IN A TERTIARY HERNIA CENTER(THC): PROSPECTIVE STUDY OF OUTCOMES OVER 18 YEARS AND 1842 OPEN PREPERITONEAL VENTRAL HERNIA REPAIRS(OPPVHR)

Background

Over 18 years, a THC frequently changed patient-care protocols according to repeated reviews of our prospectively collected data outcomes, which have been published in peer-reviewed journals. This study aimed to describe these progressive, evidence-based changes and the subsequent results in PP-VHR.

Methods

Prospective, tertiary hernia center data(2004–2021) was examined for patients undergoing midline open PP-VHR with mesh. “Early”(2004–2012) and “Recent”(2013–2021) groups were based on surgery date.

Results

Comparison of Early(n=675) versus Recent(n=1,167) groups showed that Recent patients were older (56.9±12.6vs58.7±12.1 years;p&lt;0.001), more comorbid(3.6±2.2vs5.2±2.6 diagnoses;p&lt;0.001), lower BMI(33.5±8.3 vs 32.0±6.8 kg/m2; p=0.003), more prior failed VHR(46.5% vs 60.8%; p&lt;0.001), larger hernia defects(199.7±232.8vs214.4±170.5 cm2;p&lt;0.001), more CDC-class 3/4 wounds(11.3%vs18.6%;p&lt;0.001), more biologic mesh(10.5% vs 25.4%;p&lt;0.001), component separations(CST; 22.5%vs45.7%;p&lt;0.001), and more pre-op Botox(0%vs12.3%;p&lt;0.01). Wound complication(26.7%vs13.2%;p&lt;0.001), mesh infection(3.1%vs0.9%;p&lt;0.01), and hernia recurrence rates decreased over time(7.1%vs2.4%;p&lt;0.001) with long-term follow-up(4.2±4.1vs2.2±1.8years;p&lt;0.001).

Comparing respective multivariable analyses (Early vs Recent), wound complications were associated with panniculectomy(OR[95%CI]:2.9[1.9–4.5],p&lt;0.001 vs 2.1[1.4–3.3],p&lt;0.01), contaminated wounds(2.1[1.1–3.7],p=0.02 vs 1.8[1.1–3.1],p=0.02), anterior CST(1.8[1.1–2.9], p=0.02 vs 3.2[1.9–5.3],p&lt;0.01), and operative time(per minute:1.01[1.008–1.015], p&lt;0.01 vs 1.004[1.001–1.007], p&lt;0.01) in both time periods. Diabetes(2.6[1.7–4.0],p&lt;0.01) and tobacco(1.8[1.1–2.9], p=0.02) were only significant in the Early group with the Recent group requirements for preop smoking cessation and a HgbA1C of &lt;7.2. In both groups, recurrence was associated with wound complication(8.9[4.1–20.1],p&lt;0.01 vs 3.4[1.3–8.2].p&lt;0.01) and prior failed VHR hernias(4.9[2.3–11.5],p&lt;0.01 vs 2.1[1.1–4.2],p=0.036).

Conclusion

Despite increased patient and hernia complexity over time, detecting and implementing best practices, as determined by repeated self-analysis of a THC's data, significantly improved patient outcomes, including wound and mesh complications and recurrence.

OC-061 IMAGE-BASED DEEP LEARNING MODELS (DLMS) IDENTIFY ABDOMINAL WALL RECONSTRUCTION (AWR) PATIENTS RECEIVING PREOPERATIVE BOTULINUM TOXIN A (BTA) WHO REQUIRE COMPONENT SEPARATION TECHNIQUE (CST)

Aim

Preoperative BTA facilitates muscle/fascia elongation and fascial closure, which increases the durability of hernia repair and may reduce requirement for CST. The aim of this study was to develop image-based DLMs that predict whether patient will require CST if injected with BTA prior to surgery.

Methods

An institutional database was used to identify AWR patients who received preoperative BTA and had preoperative CT imaging. Axial CT cuts of the hernias were rendered to train and develop a DLM. The primary outcome was a ROC for predicting CST. The DLM was tested on CT scans from a pre-identified subset of patients who underwent CST and did not receive preoperative BTA.

Results

There were 116 patients who met criteria (4,580 CT images). Of these patients, 69 (59.5%) required CST (2884 images); 47 patients (40.5%) did not undergo CST (1,696 images). The DLM ROC was 0.78 (Figure 1); accuracy, sensitivity, and specificity were 0.79, 0.86, and 0.68, respectively. There were 98 patients in the test set; 57 (58.1%) were predicted to require CST and 41 (41.9%) were not. For patients with an M1 hernia component, 21.1% were predicted to be spared CST versus 46.8% those with an M2-M5 hernia component (p=0.04).

Figure 1 Model Performance for CST Prediction

Conclusions

Image-based DLMs accurately predicted which patients receiving preoperative BTA may require CST. When the DLM was applied to a test set, patients with an M1 hernias were very likely to require CST, which is consistent with previously reported data, further validating the model.

OC-032 IMAGE-BASED DEEP LEARNING MODELS (DLMS) TO PREDICT LONG TERM QUALITY OF LIFE (QOL) FOLLOWING ABDOMINAL WALL RECONSTRUCTION (AWR)

Aim

To apply image-based DLMs to predict post-operative QOL following AWR.

Materials & Methods

A prospective, institutional hernia-database was queried for patients with preoperative abdominal CT-imaging, a preoperative and 1-year postoperative Carolinas Comfort Scale(CCS) survey, and no recurrence. “Symptomatic” was defined as CCS-score≥2(2=mild and bothersome). Google Xception existing architecture model was used with ImageNet database pre-initialized weights to classify symptomatic and non-symptomatic patients. Patients were divided into 80:20-training:testing samples for model generation and evaluation. Model training, test accuracies, and loss-functions were evaluated to determine performance and discriminative ability.

Results

Of 244 patients, mean age was 60.4±11.8 years, mean BMI:33.0±7.1kg/m2, female:57.1%, tobacco use:14.3%, diabetic: 24.5%. Median[IQR] hernia defect size was Exactly 180cm2[90–324]; 66.1% had a failed repair. CDC wound classifications Included: 75.9% class-I, 8.3% class-II, 9.1% class-III, 6.6% class-IV. Preoperatively, hernia-related pain(70.2%) and movement limitations(72.3%) were common. Mesh position was predominantly preperitoneal(91.6%). Median[IQR] mesh size was 900cm2[572–1050]. Anterior component separation was required in 17.9% and posterior in 20.4%.

One-year postoperatively, reported symptoms included: mesh sensation-39.5%, discomfort-37.8%, movement limitations-37.0%.

DLMs utilized 6,441-CT-images(5,097 training-sample). Proportions of symptomatic patients were 48.9%(85/174) in the training-sample and 50%(35/70) in the test-sample. Highest DLM training accuracy was 85.37%(loss=0.3766) at epoch 15/50 with 79.30%(loss=0.3766) comparative validation accuracy, demonstrating strong discriminative ability in model classification between symptomatic and asymptomatic patients. Lower accuracy due to model overfitting was observed after 50 epochs.

Conclusions

Image-based DLMs using standard, preoperative CT images very successfully predicted 1-year AWR QOL. The impact of DLMs on preoperative counseling/consent for surgery could be revolutionary.

V-014 OPEN REPAIR OF PRIMARY LUMBAR HERNIA WITH PREPERITONEAL MESH

This video presents an open repair of a primary lumbar hernia with preperitoneal mesh performed at a high-volume hernia center. The patient was a 71-year-old female referred due to chronic pain from a primary hernia of the right superior lumbar triangle.

The patient was positioned in the left lateral decubitus position with the bed slightly flexed. A skin incision was created sharply, and electrocautery used to dissect subcutaneous tissue and superficial fascia, revealing the hernia contents.

Circumferential lysis of adhesions was performed with blunt and cautery dissection to release the hernia contents from the abdominal wall. Once the hernia contents were mobilized, they were then carefully reduced through the fascial defect. The hernia defect measured approximately 3.5×3.5 cm.

Next, the preperitoneal space was circumferentially developed. This was done primarily with blunt finger dissection, using a rolling motion to direct pressure towards the abdominal wall and sweep the peritoneum and other attachments down. Larger attachments are gently retracted and divided with electrocautery. The preperitoneal space was measured at 20×19 cm and the mesh trimmed to those dimensions. The mesh was carefully laid flat in the preperitoneal space. No mesh fixation was required.

Fascial edges were dissected free for 1–2cm surrounding the defect. Two running 1–0 PDS sutures were used to close the hernia defect. A closed-suction drain was placed superficial to the fascia to minimize seroma formation. The superficial fascia and dermis were closed in layers. The patient had a routine hospital course and was discharged on post-operative day 3.

National epidemiologic trends (2008-2018) in the United States for the incidence and expenditures associated with incisional hernia in relation to abdominal surgery

PURPOSE

It is unknown whether the trend of rising incisional hernia (IH) repair (IHR) incidence and costs until 2011 currently persists. We aimed to evaluate how the IHR procedure incidence, cost and patient risk-profile have changed over the last decade relative to all abdominal surgeries (AS).

METHODS

Repeated cross-sectional analysis of 38,512,737 patients undergoing inpatient 4AS including IHR within the 2008-2018 National Inpatient Sample. Yearly incidence (procedures/1,000,000 people [PMP]), hospital costs, surgical and patient characteristics were compared between IHR and AS using generalized linear and multinomial regression.

RESULTS

Between 2008-2018, 3.1% of AS were IHR (1,200,568/38,512,737). There was a steeper decrease in the incidence of AS (356.5 PMP/year) compared to IHR procedures (12.0 PMP/year) which resulted in the IHR burden relative to AS (2008-2018: 12,576.3 to 9,113.4 PMP; trend difference P < 0.01). National costs averaged $47.9 and 1.7 billion/year for AS and IHR, respectively. From 2008-2018, procedure costs increased significantly for AS (68.2%) and IHR (74.6%; trends P < 0.01). Open IHR downtrended (42.2%), whereas laparoscopic (511.1%) and robotic (19,301%) uptrended significantly (trends P < 0.01). For both AS and IHR, the proportion of older (65-85y), Black and Hispanic, publicly-insured, and low-income patients, with higher comorbidity burden, undergoing elective procedures at small- and medium-sized hospitals uptrended significantly (all P < 0.01).

CONCLUSION

IH persists as a healthcare burden as demonstrated by the increased proportion of IHR relative to all AS, disproportionate presence of high-risk patients that undergo these procedures, and increased costs. Targeted efforts for IH prevention have the potential of decreasing $17 M/year in costs for every 1% reduction.

Perioperative optimization in complex abdominal wall hernias: Delphi consensus statement

BACKGROUND

The incidence of incisional hernia after major abdominal surgery via a midline laparotomy is 20-41 per cent with short-term follow-up, and over 50 per cent in those surviving an abdominal catastrophe. Abdominal wall reconstruction (AWR) requires complex operations, often involving mesh resection, management of scarred skin, fistula takedown, component separation or flap reconstruction. Patients tend to have more complex conditions, with multiple co-morbidities predisposing them to a vicious cycle of complications and, subsequently, hernia recurrence. Currently there appears to be variance in perioperative practice and minimal guidance globally. The aim of this Delphi consensus was to provide a clear benchmark of care for the preoperative assessment and perioperative optimization of patients undergoing AWR.

METHODS

The Delphi method was used to achieve consensus from invited experts in the field of AWR. Thirty-two hernia surgeons from recognized hernia societies globally took part. The process included two rounds of anonymous web-based voting with response analysis and formal feedback, concluding with a live round of voting followed by discussion at an international conference. Consensus for a strong recommendation was achieved with 80 per cent agreement, and a weak recommendation with 75 per cent agreement.

RESULTS

Consensus was obtained on 52 statements including surgical assessment, preoperative assessment, perioperative optimization, multidisciplinary team and decision-making, and quality-of-life assessment. Forty-six achieved over 80 per cent agreement; 14 statements achieved over 95 per cent agreement.

CONCLUSION

Clear consensus recommendations from a global group of experts in the AWR field are presented in this study. These should be used as a baseline for surgeons and centres managing abdominal wall hernias and performing complex AWR.

Robotic Sugarbaker parastomal hernia repair: technique and outcomes

PURPOSE

To present a novel technique for the repair of parastomal hernias.

METHODS

A total of 15 patients underwent parastomal hernia repair. A robotic Sugarbaker technique was utilized for repair. The fascial defect was closed prior to robotic intraperitoneal placement of the mesh. Baseline demographics of the patients were obtained, and intra-operative and post-operative outcomes were tracked.

RESULTS

The etiology of the ostomies was oncologic in all but three patients. Five of the stomas were urostomies (33.3%). Patient characteristics were as follows: age 64.9.1 ± 9.3 years, BMI 30.1 ± 4.7 kg/m², smoking history 60.0%, and diabetes 6.7%. The mean size of the hernia defect was 46.0 ± 40.1 cm² with a mesh size of 372.0 ± 101.2 cm². The mean operative time was 182.0 ± 51.9 min. In seven patients, an inferolateral preperitoneal flap was created for mesh placement. Intraoperatively, only one enterotomy was made during dissection, which was repaired without complication. The mean length of stay was 4.2 ± 1.9 days. There was only one hernia recurrence (6.7%). There were no wound complications, surgical site infections, or mesh infections. A mean follow-up time of 14.2 ± 9.4 months was achieved.

CONCLUSIONS

Robotic Sugarbaker parastomal hernia repair is a safe and effective technique. The results demonstrate the feasibility of fascial closure with this technique and a low recurrence rate. The authors propose this technique should be widely considered for parastomal hernia repair.

Chronic immunosuppressant use in colorectal cancer patients worsens postoperative morbidity and mortality through septic complications in a propensity-matched analysis

AIM

Chronic immunosuppressant use increases the risk of septic complications after colectomy; however, adverse effects on other organ systems remain poorly understood. The aim of this study was to evaluate the multisystem organ effect(s) of chronic immunosuppressant(s) in colorectal cancer patients.

METHODS

This was a retrospective study. The American College of Surgeons National Surgical Quality Improvement database (2005-2012) was queried. The primary end-points were 30-day mortality and 30-day morbidity after colectomy in patients on chronic immunosuppressant(s) compared to a non-immunosuppressant cohort.

RESULTS

In total, 50 766 patients were identified, with 1203 (2.4%) taking chronic immunosuppressant(s). After propensity matching, 1197 patients in each cohort were evaluated with no differences seen in age, body mass index, male sex, wound classification, emergency case status, the presence of preoperative sepsis or operative time. On outcome analysis, 30-day mortality (5.7% vs 3.4%, P < 0.001) and 30-day overall morbidity (35.4% vs 29.0%, P = 0.001) were higher in patients on chronic immunosuppressant(s). Septic complications (10.6% vs 7.9%, P = 0.02) and surgical site infections (15.3% vs 12.3%, P = 0.03) were elevated with chronic immunosuppressant(s). There were no differences in cardiovascular, pulmonary, renal or neurological complications. Chronic immunosuppressant patients demonstrated longer total hospital stay (11.4 ± 11.7 vs 9.5 ± 9.4 days, P < 0.001) and postoperative length of stay (9.4 ± 9.2 vs 8.1 ± 7.6 days, P < 0.001). The limitation was that this was a retrospective study using a clinical dataset.

CONCLUSION

In this study, immunosuppressant use is associated with worsened infective complications, without contributing to organ-specific complications following colectomy. Significant thought should be given to anastomosis vs stoma creation to possibly prevent worsened morbidity and mortality. Future study is required to determine specific pathways for risk reduction.

Home intravenous versus oral antibiotics following appendectomy for perforated appendicitis in children: a randomized controlled trial

PURPOSE

To compare the effect of home intravenous (IV) versus oral antibiotic therapy on complication rates and resource utilization following appendectomy for perforated appendicitis.

METHODS

This was a randomized controlled trial of patients aged 4-17 with surgically treated perforated appendicitis from January 2011 to November 2013. Perforation was defined intraoperatively and divided into three grades: I-contained perforation, II-localized contamination to right gutter/pelvis, and III-diffuse contamination. Patients were randomized to complete a ten-day course of home antibiotic therapy with either IV ertapenem or oral amoxicillin-clavulanate. Thirty-day postoperative complication rates including abscess, readmission, wound infection, and charges were compared.

RESULTS

Eighty-two patients were enrolled. Forty four (54%) were randomized to the IV group and 38 (46%) to the oral group. IV patients were older (12.3 ± 3.6 versus 10.1 ± 3.6, p < 0.05) with higher BMI (20.9 ± 5.8 versus 17.9 ± 3.5, p < 0.05). There were no differences in gender, comorbidities, or perforation grade (I-20.4% vs. 26.3%, II-36.4% vs. 34.2%, III-43.2% vs. 39.5%, all p > 0.05). Comparing IV to oral, there was no difference in length of stay (4.4 ± 1.5 versus 4.4 ± 2.0 days, p > 0.05), postoperative abscess rate (11.6% vs. 8.1%, p > 0.05), or readmission rate (14.0% vs. 16.2%, p > 0.05). Hospital and outpatient charges were higher in the IV group (p < 0.0001).

CONCLUSION

Oral antibiotics had equivalent outcomes and incurred fewer charges than IV antibiotics following appendectomy for perforated appendicitis.

Emergent Laparoscopic Ventral Hernia Repairs

BACKGROUND

Emergent repairs of incarcerated and strangulated ventral hernia repairs (VHR) are associated with higher perioperative morbidity and mortality than those repaired electively. Despite increasing utilization of minimally invasive techniques in elective repairs, the role for laparoscopy in emergent VHR is not well defined, and its feasibility has been demonstrated only in single center studies.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database (2009-2016) was queried for emergent VHR. Laparoscopic and open techniques were compared using univariate and multivariate analyses.

RESULTS

A total of 11,075 patients who underwent emergent ventral and incisional hernia repairs were identified: 85.5% open ventral hernia repair (OVHR), 14.5% laparoscopic ventral hernia repair (LVHR). Patients who underwent emergent OVHRs were older, more comorbid, and more likely to be septic at the time of surgery than those undergoing emergent LVHRs. Emergent OVHR patients were more likely to have minor complications (22.1% versus 11.0%; OR 1.7; 95% CI 1.069-2.834). After controlling for confounding variables, LVHR and OVHR had similar outcomes, with the exception of higher rates of superficial surgical site infection in OVHR (5.0% versus 1.8%; odd's ratio (OR) 2.7; 95% confidence interval (CI) 1.176-6.138). Following multivariate analysis, laparoscopic approach demonstrated similar outcomes in major complications, reoperation, and 30-d mortality compared to open repairs. However, when controlling for other confounding factors, LVHR had reduced length of stay compared to OVHR (6.7 versus 4.0 d; 1.6 d longer, standard error 0.77, P < 0.03).

CONCLUSIONS

Emergent LVHR is associated with fewer superficial surgical site infection and shorter length of stay than OVHR but no difference in major complications, reoperation or 30-d mortality is associated with LVHR in the emergency setting.

Intraoperative indocyanine green fluorescence angiography to predict wound complications in complex ventral hernia repair

INTRODUCTION

Complex ventral hernia repair (VHR) is associated with a greater than 30% wound complication rate. Perfusion mapping using indocyanine green fluorescence angiography (ICG-FA) has been demonstrated to predict skin and soft tissue necrosis in many reconstructive procedures; however, it has yet to be evaluated in VHR.

METHODS

Patients undergoing complex VHR involving component separation and/or extensive subcutaneous advancement flaps were included in a prospective, blinded study. Patients with active infection were excluded. ICG-FA was performed prior to incision and prior to closure, but the surgeon was not allowed to view it. An additional blinded surgeon documented wound complications and evaluated postoperative photographs. The operative ICG-FA was reviewed blinded, and investigators were then unblinded to determine its ability to predict wound complications.

RESULTS

Fifteen consecutive patients were enrolled with mean age of 56.1 years and average BMI of 34.9, of which 60% were female. Most (73.3%) had prior hernia repairs (average of 1.8 prior repairs). Mean defect area was 210.4 cm2, mean OR time was 206 min, 66.6% of patients underwent concomitant panniculectomy, and 40% had component separation. Mean follow-up was 7 months. Two patients developed wound breakdown requiring reoperation, while 1 had significant fat necrosis and another a wound infection, requiring operative intervention. ICG-FA was objectively reviewed and predicted all 4 wound complications. Of the 12 patients without complications, 1 had an area of low perfusion on ICG-FA. This study found a sensitivity of 100% and specificity of 90.9% for predicting wound complications using ICG-FA.

CONCLUSION

In complex VHR patients, subcutaneous perfusion mapping with ICG-FA is very sensitive and has the potential to reduce cost and improve patient quality of life by reducing wound complications and reoperation.

National outcomes of laparoscopic Heller myotomy: operative complications and risk factors for adverse events

INTRODUCTION

Laparoscopic Heller myotomy (LHM) has supplanted an open approach due to decreased operative morbidity. Our goal was to quantify the incidence of peri-operative complications and identify risk factors for adverse outcomes in LHM.

METHODS

All LHM were queried from 2005 to 2011 from the National Surgical Quality Improvement Program database. Adverse outcomes were identified, and univariate and stepwise logistic regression (MVR) was then performed to quantify association.

RESULTS

There were 1,237 LHM in the study period. Patient averages were: age 51.9 ± 16.8 years, BMI 27.3 ± 6.6 kg/m(2), Charlson comorbidity index (CCI) 0.2 ± 0.6. 15.3 % had >10 % body mass loss in the preoperative 6 months. During surgery, 10.2 % underwent concomitant EGD, and mean operative time was 141.6 ± 63.4 min. There were 7(0.06 %) wound complications, 22(1.8 %) general complications, and 30(2.4 %) major complications. Average length of stay (LOS) was 2.8 ± 5.5 days. The rate of readmission and reoperation were 3.1 and 2.3 %, respectively, and there were 4(0.03 %) deaths. General and major complications were associated with alcohol use, pack-years of smoking, weight loss, history of stroke, radiation therapy, and longer operative times (p < 0.05); however, these factors did not remain significant on MVR (p > 0.05). Operative time was found to be significantly longer by 35.3 min for inpatients, 43.1 min in functionally dependent patients, 50.0 min in preoperative septic patients, and 17.2 min with concomitant EGD (p < 0.01 for all). LOS was found to be longer by 1.9 days for inpatients, 1.8 days in ASA category ≥3, and 1.2 days per one point increase in CCI (p < 0.001 for all).

CONCLUSION

LHM is being performed nationally with a low incidence of operative complications and mortality. General and major complications following LHM are associated with patient alcohol use, pack-years of smoking, weight loss, history of stroke, radiation therapy, and longer operative times. Additionally, independent predictors of longer operative time and LOS were identified.

Arterial vs venous blood gas differences during hemorrhagic shock

AIM: To characterize differences of arterial (ABG) and venous (VBG) blood gas analysis in a rabbit model of hemorrhagic shock.

METHODS: Following baseline arterial and venous blood gas analysis, fifty anesthetized, ventilated New Zealand white rabbits were hemorrhaged to and maintained at a mean arterial pressure of 40 mmHg until a state of shock was obtained, as defined by arterial pH ≤ 7.2 and base deficit ≤ -15 mmol/L. Simultaneous ABG and VBG were obtained at 3 minute intervals. Comparisons of pH, base deficit, pCO₂, and arteriovenous (a-v) differences were then made between ABG and VBG at baseline and shock states. Statistical analysis was applied where appropriate with a significance of P < 0.05.

RESULTS: All 50 animals were hemorrhaged to shock status and euthanized; no unexpected loss occurred. Significant differences were noted between baseline and shock states in blood gases for the following parameters: pH was significantly decreased in both arterial (7.39 ± 0.12 to 7.14 ± 0.18) and venous blood gases (7.35 ± 0.15 to 6.98 ± 0.26, P < 0.05), base deficit was significantly increased for arterial (-0.9 ± 3.9 mEq/L vs -17.8 ± 2.2 mEq/L) and venous blood gasses (-0.8 ± 3.8 mEq/L vs -15.3 ± 4.1 mEq/L, P < 0.05). pCO₂ trends (baseline to shock) demonstrated a decrease in arterial blood (40.0 ± 9.1 mmHg vs 28.9 ± 7.1 mmHg) but an increase in venous blood (46.0 ± 10.1 mmHg vs 62.8 ± 15.3 mmHg), although these trends were non-significant. For calculated arteriovenous differences between baseline and shock states, only the pCO₂ difference was shown to be significant during shock.

CONCLUSION: In this rabbit model, significant differences exist in blood gas measurements for arterial and venous blood after hemorrhagic shock. A widened pCO₂ a-v difference during hemorrhage, reflective of poor tissue oxygenation, may be a better indicator of impending shock.

Immunohistochemical analysis of host reaction to heavyweight-, reduced-weight-, and expanded polytetrafluoroethylene (ePTFE)-based meshes after short- and long-term intraabdominal implantations

BACKGROUND

Prosthetic meshes induce a variety of inflammatory changes in the host, which may lead to excessive scarring with detrimental clinical consequences, especially in the long term. This study aimed to characterize the degree of short- and long-term inflammatory changes induced by common prosthetic meshes.

METHODS

Twenty 4 x 4-cm samples each of expanded polytetrafluoroethylene (ePTFE), heavyweight polypropylene (hPP), ePTFE/heavyweight polypropylene (ePTFE/hPP), and reduced-weight polypropylene/regenerated cellulose (rPP) were implanted intraperitoneally in 40 rabbits for 4 or 12 months. After explantation, samples of mesh/tissue complex were analyzed for the degrees of cellular apoptosis (enzyme-linked immunoassay [ELISA]) and cellular turnover (mouse monoclonal antibody).

RESULTS

In the short term, the degree of apoptosis in the hPP mesh was significantly higher than in the ePTFE and rPP groups. Similarly, it was higher in the ePTFE/hPP group than in either the ePTFE or the rPP group. The amount of Ki-67-positive cells was significantly higher in the hPP group than in the ePTFE or rPP group. The cell turnover in the ePTFE/hPP group was similar to that in the hPP group, but significantly higher than in either the ePTFE or the rPP group. The rPP group, in turn, had a higher Ki-67 score than the ePTFE group. In the long term, both the degree of apoptosis and Ki-67 positivity were significantly lower in the rPP and ePTFE groups than in either the ePTFE/hPP or the hPP group. A significant decrease in Ki-67 scores between the short and long-term groups was found only in the rPP group.

CONCLUSION

In the short term, heavyweight polypropylene-based meshes were associated with significantly higher cell proliferation and death. A significantly higher degree of apoptosis and cell turnover were associated with heavyweight polypropylene-based meshes even 1 year after implantation, indicating ongoing inflammation and scar remodeling. On the other hand, ePTFE and reduced-weight polypropylene meshes were associated with nearly physiologic levels of inflammatory markers. Overall, an exaggerated and persistent host foreign body response to heavyweight polypropylene-based meshes indicates poor biocompatibility, with potential detrimental clinical sequela.

Laparoscopic ventral hernia repair (LVHR) in morbidly obese patients

OBJECTIVE

The aim of this study was to evaluate our experience with LVHR in morbidly obese patients (BMI >40) and to compare their outcomes to those of patients with lower BMI.

METHODS

Data on adult (>18 years old) patients who underwent LVHR with mesh over the last 13 years performed by four experienced surgeons were collected retrospectively and from a previously collected database. Of the 1,071 patients, 901 had completed LVHR and were available for follow-up. One hundred and thirty-four patients (group A) met BMI criteria for morbid obesity (>or=40, mean 46), 767 patients had BMI < 40, mean 30 (group B). The follow-up time ranged from 1 to 91 months. The Wilcoxon rank sum test was used for nonparametric data analysis. Outcomes were stratified on the follow up time and analyzed using Cochran-Mantel-Haenszel methodology.

RESULTS

The groups did not differ in terms of ASA score, previous surgery and conversion rate (p=0.22, 0.32 and 0.23). Morbidly obese patients were younger (48.3 vs. 54; p<0.01) and were more often female (p=0.02), but this did not correlate with outcome. Group A also had longer operative time (154 vs. 119 min, p<0.01) and hospital stay (3.6 vs. 2.4 days, p=0.03). Mesh size was significantly larger in group A (449 vs. 349 cm(2), p=002). During mean follow-up time of 19 months hernia recurrence was 8.3% in group A and 2.9% in group B (p=0.003), with an odds ratio of 4.3 (95% CI 1.9-9.9). However, there was no significant difference in the rate of complications (19.7 vs. 15.3%; p=0.46).

CONCLUSIONS

LVHR in the morbidly obese population is both safe and feasible, although there is a higher, but still acceptable recurrence rate. Despite the increased risk for recurrence, LVHR in morbidly obese patients minimizes the potential wound and mesh complications that frequently occur for open mesh repair in this group of patients.

Laparoscopic parastomal hernia repair using a nonslit mesh technique

BACKGROUND

The management of parastomal hernia is associated with high morbidity and recurrence rates (20-70%). This study investigated a novel laparoscopic approach and evaluated its outcomes.

METHODS

A consecutive multi-institutional series of patients undergoing parastomal hernia repair between 2001 and 2005 were analyzed retrospectively. Laparoscopy was used with modification of the open Sugarbaker technique. A nonslit expanded polytetrafluoroethylene (ePTFE) mesh was placed to provide 5-cm overlay coverage of the stoma and defect. Transfascial sutures secured the mesh, allowing the stoma to exit from the lateral edge. Five advanced laparoscopic surgeons performed all the procedures. The primary outcome measure was hernia recurrence.

RESULTS

A total of 25 patients with a mean age of 60 years and a body mass index of 29 kg/m2 underwent surgery. Six of these patients had undergone previous mesh stoma revisions. The mean size of the hernia defect was 64 cm2, and the mean size of the mesh was 365 cm2. There were no conversions to open surgery. The overall postoperative morbidity was 23%, and the mean hospital length of stay was 3.3 days. One patient died of pulmonary complications; one patient had a trocar-site infection; and one patient had a mesh infection requiring mesh removal. During a median follow-up period of 19 months (range, 2-38 months), 4% (1/25) of the patients experienced recurrence.

CONCLUSION

On the basis of this large case series, the laparoscopic nonslit mesh technique for the repair of parastomal hernias seems to be a promising approach for the reduction of hernia recurrence in experienced hands.

Severely disordered esophageal peristalsis is not a contraindication to laparoscopic Nissen fundoplication

BACKGROUND

Laparoscopic Nissen fundoplication (LNF) is the preferred operation for the control of gastroesophageal reflux disease (GERD). The use of a full fundoplication for patients with esophageal dysmotility is controversial. Although LNF is known to be superior to a partial wrap for patients with weak peristalsis, its efficacy for patients with severe dysmotility is unknown. We hypothesized that LNF is also acceptable for patients with severe esophageal dysmotility.

METHODS

A multicenter retrospective review of consecutive patients with severe esophageal dysmotility who underwent an LNF was performed. Severe dysmotility was defined by manometry showing an esophageal amplitude of 30 mmHg or less and/or 70% or more nonperistaltic esophageal body contractions.

RESULTS

In this study, 48 patients with severe esophageal dysmotility underwent LNF. All the patients presented with symptoms of GERD, and 19 (39%) had preoperative dysphagia. A total of 10 patients had impaired esophageal body contractions, whereas 32 patients had an abnormal esophageal amplitude, and 6 patients had both. The average abnormal esophageal amplitude was 24.9 +/- 5.2 mmHg (range, 6.0-30 mmHg). The mean percentage of nonperistaltic esophageal body contractions was 79.4% +/- 8.3% (range, 70-100%). There were no intraoperative complications and no conversions. Postoperatively, early dysphagia occurred in 35 patients (73%). Five patients were treated with esophageal dilation, which was successful in three cases. One patient required a reoperative fundoplication. Overall, persistent dysphagia was found in two patients (4.2%), including one patient with severe preoperative dysphagia, which improved postoperatively. Abnormal peristalsis and/or distal amplitude improved postoperatively in 12 (80%) of retested patients. There were no cases of Barrett's progression to dysplasia or carcinoma. During an average follow-up period of 25.4 months (range, 1-46 months), eight patients (16%) were receiving antireflux medications, with six of these showing normal esophageal pH study results.

CONCLUSION

The LNF procedure provides low rates of reflux recurrence with little long-term postoperative dysphagia experienced by patients with severely disordered esophageal peristalsis. Effective fundoplication improved esophageal motility for most of the patients. A 360 degrees fundoplication should not be contraindicated for patients with severe esophageal dysmotility.

Laparoscopic ventral hernia repair: a single center experience

A retrospective chart review at the Carolinas Medical Center was performed on all patients who underwent laparoscopic ventral hernia repair (LVHR) from July 1998 through December 2003. LVHR was successfully completed in 270 of the 277 patients, or 98%, in whom it was attempted. Half of the patients (138/277) had at least one previous failed repair. The average defect measured 143.3 cm(2), and mesh was used in all repairs. The mean operating time was 168.3 min, mean blood loss was 50 cc, and average length of hospitalization was 3.0 days. Thirty-four complications occurred in 31 patients (11%). Only two mesh infections occurred (0.7%). At a mean follow-up period of 21 months, the rate of hernia recurrence was 4.7%. As experience grows and length of follow-up expands, LVHR may become the preferred approach for ventral hernia in difficult patients, especially obese patients and patients who have failed prior open repairs.

In vitro infectability of prosthetic mesh by methicillin-resistant Staphylococcus aureus

Although mesh use is important for effective herniorrhaphy in adults, prosthetic infections can cause serious morbidity. Bacterial adherence to the mesh is a known precursor to prosthetic infection. We compared the ability of common mesh prosthetics to resist bacterial adherence. The meshes studied included polypropylene (Marlex, expanded polytetrafluoroethylene (PTFE) with and without silver chlorhexidine coating (DualMesh Plus and Dualmesh) composite meshes (Composix E/X, Proceed, and Parietex Composite) and lightweight polypropylene meshes (TiMesh, Ultrapro, and Vypro). Fifteen samples of each mesh type were individually inoculated with a suspension of 10(8 )methicillin-resistant Staphylococcus aureus (MRSA) in tryptic soy broth. After incubation at 37 degrees C for 1 h, the mesh pieces were then removed and serially washed. The colony-forming units (CFU) of MRSA present in the initial inoculum, at the end of the 1-h warm-water bath (broth count), and the pooled washes (wash count), were determined using serial dilutions and spot plating. The bacteria not accounted for in the broth or wash counts were considered adhered to the mesh. Samples of each mesh type were also analyzed using scanning electron microscopy (SEM). Data are presented as the mean percentage adherence with ANOVA and Tukey's test used to determine significance (P<0.05). The DualMesh Plus mesh had no detectable MRSA in the broth or the pooled wash samples. Dualmesh had less adherence compared with Marlex, Proceed, and Vypro (P<0.05). Conversely, Vypro had a statistically higher adherence (96%, P<0.05) as compared to TiMesh, Ultrapro, Composix E/X, and Parietex Composite. SEM confirmed bacterial adherence to all the mesh types except DualMesh Plus. The ability of a biomaterial to resist infection has an important clinical significance. DualMesh Plus, due to its antimicrobial coating, is the only mesh type of the nine tested that demonstrated a bactericidal property. Standard PTFE (Dualmesh) also had less bacterial adherence. Vypro demonstrated an increase in bacterial adherence; this was possibly due to the multifilament polyglactin 910 weaved within the prolene component of the mesh.

Do patient or hospital demographics predict cholecystectomy outcomes? A nationwide study of 93,578 patients

BACKGROUND

The purpose of this study was to examine the influence of patient and hospital demographics on cholecystectomy outcomes.

METHODS

Year 2000 data from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample database was obtained for all patients undergoing inpatient cholecystectomy at 994 nationwide hospitals. Differences (p < 0.05) were determined using standard statistical methods.

RESULTS

Of 93,578 cholecystectomies performed, 73.4% were performed laparoscopically. Length of hospital stay (LOS), charges, morbidity, and mortality were significantly less for laparoscopic cholecystectomy (LC). Increasing patient age was associated with increased LOS, charges, morbidity, mortality, and a decreased LC rate. Charges, LOS, morbidity, and mortality were highest for males with a lower LC rate than for females Mortality and LOS were higher, whereas morbidity was lower for African Americans than for whites. Hispanics had the shortest LOS, as well as the lowest morbidity and mortality rates. Laparoscopic cholecystectomy was performed more commonly for Hispanics than for whites or African Americans, with lower charges for whites. Medicare-insured patients incurred longer LOS as well as higher charges, morbidity, and mortality than Medicaid, private, and self-pay patients, and were the least likely to undergo LC. As median income decreases, LOS increases, and morbidity decreases with no mortality effect. Teaching hospitals had a longer LOS, higher charges, and mortality, and a lower LC rate, with no difference in morbidity, than nonteaching centers. As hospital size (number of beds) increased, LOS, and charges increased, with no difference in morbidity. Large hospitals had the highest mortality rates and the lowest incidence of LC. Urban hospitals had higher LOS and charges with a lower LC rate than rural hospitals. After control was used for all other covariates, increased age was a predictor of increased morbidity. Female gender, LC, and intraoperative cholangiogram all predicted decreased morbidity. Increased age, complications, and emergency surgery predicted increased mortality, with laparoscopy and intraoperative cholangiogram having protective effects. Patient income, insurance status, and race did not play a role in morbidity or mortality. Academic or teaching status of the hospital also did not influence patient outcomes.

CONCLUSIONS

Patient and hospital demographics do affect the outcomes of patients undergoing inpatient cholecystectomy. Although male gender, African American race, Medicare-insured status, and large, urban hospitals are associated with less favorable cholecystectomy outcomes, only increased age predicts increased morbidity, whereas female gender, laparoscopy, and cholangiogram are protective. Increased age, complications, and emergency surgery predict mortality, with laparoscopy and intraoperative cholangiogram having protective effects.

Laparoscopic management of median arcuate ligament syndrome

Median arcuate ligament syndrome is a rare disorder resulting from luminal narrowing of the celiac artery by the insertion of the diaphragmatic muscle fibers or fibrous bands of the celiac nervous plexus. The syndrome is characterized by weight loss, postprandial abdominal pain, nausea, vomiting, and an epigastric bruit. Surgical management entails complete division of the median arcuate ligament. The video demonstrates the laparoscopic release of the median arcuate ligament in a patient with median arcuate ligament syndrome. The patient is a 22-year-old male with a 6-month history of epigastric abdominal pain, nausea, vomiting, a 140-lb. weight loss, and an epigastric bruit on physical exam. Aortography demonstrated a >or=90% extrinsic compression of the celiac artery. A full laparoscopic skeletonization of the celiac artery and branch vessels was performed. Intraoperative duplex U/S demonstrated flow rate reduction after the median arcuate ligament release. A postoperative CT angiogram demonstrated no residual stenosis. The patient was discharged on postoperative day 3 and remained asymptomatic after 7 months of follow-up. Laparoscopic release of the median arcuate ligament is a novel approach to the management of celiac artery compression syndrome. The role of minimally invasive techniques to manage median arcuate ligament syndrome is evolving but they appear to be a safe alternative to open surgery.

Evaluation of adhesion formation, mesh fixation strength, and hydroxyproline content after intraabdominal placement of polytetrafluoroethylene mesh secured using titanium spiral tacks, nitinol anchors, and polypropylene suture or polyglactin 910 suture

BACKGROUND

The purpose of this study is to evaluate fixation methods for polytetrafluoroethylene (ePTFE) mesh with an in vivo model of laparoscopic ventral hernia repair.

METHODS

In 40 New Zealand white rabbits, a 4 x 4-cm ePTFE mesh (n = 80, two per animal) was attached to an intact peritoneum with polyglactin 910 (PG 910) (n = 20) or polypropylene (PP) (n = 20) suture, titanium spiral tacks (TS) (n = 20), or nitinol anchors (NA) (n = 20). Mesh was harvested at 8 and 16 weeks for fixation strength testing, adhesion assessment, and collagen (hydroxyproline) content. Fixation strength on day 0 was determined with mesh attached to harvested abdominal wall. Statistical significance was determined as p < 0.05.

RESULTS

There was no difference in fixation strength between PP (39.1 N) and PG 910 (40.0 N) sutures at time zero. At week 8, PP (25.7 N) was significantly stronger (p < 0.05) than PG 910 (11.4 N) suture, but not at week 16. The fixation strength of TS and NA (day 0, 15.4 vs 7.4 N; week 8, 17.5 vs 15.3 N; week 16, 19.1 vs 13.8 N) was not significantly different. Fixation with PP suture was significantly (p < 0.05) stronger than that with TS and NA at day 0 (39.1, 15.4, and 7.4 N, respectively) but not at weeks 8 or 16. The fixation strength of suture decreased significantly (p < 0.05) from day 0 to week 16 (PP: day 0 = 39.1 N, week 8 = 25.7 N, week 16 = 21.4 N; PG 910: day 0 = 40.0 N, week 8 = 11.4 N, week 16 = 12.8 N). The fixation strength of NA and TS did not change significantly (NA: day 0 = 7.4 N, week 8 = 15.3 N, week 16 = 13.8 N; TS: week 0 = 15.4 N, week 8 = 17.5 N, week 16 = 19.1 N). There were no differences in adhesion area based on fixation device used; however, there were more (p < 0.05) mesh samples using NA with adhesions compared to TS and adhesion tenacity was greater (p < 0.05) compared to that of TS, PP, and PG. Hydroxyproline content at weeks 8 and 16 was similar for all fixation devices.

CONCLUSIONS

The initial fixation strength for nonabsorbable suture is significantly greater than that of the metallic fixation devices, but after 8 weeks there is no difference. Laparoscopic ventral hernia repair without transabdominal suture fixation may be predisposed to acute failure. The metallic devices have similar fixation strength, although the incidence of adhesions and tenacity of adhesions appear to be greater with the nitinol anchors. Since these devices have similar fixation strengths and most likely provide adequate supplementation to transabdominal sutures for mesh fixation after laparoscopic ventral hernia repair, their use should be based on other factors, such as their propensity for adhesions, ease of application, and cost.

Effect of carbon dioxide pneumoperitoneum and wound closure technique on port site tumor implantation in a rat model

BACKGROUND

The purpose of this study was to evaluate the effects of carbon dioxide (CO2) pneumoperitoneum and wound closure technique on port site tumor implantation.

METHODS

A standard quantity of rat mammary adenocarcinoma (SMT2A)was allowed to grow in a flank incision in Wistar-Furth rats (n = 90) for 14 days. Thereafter, 1-cm incisions were made in each animal in three quadrants. There were six control animals. The experimental animals were divided into a 60-min CO2 pneumoperitoneum group (n = 42) and a no pneumoperitoneum (n = 42) group. The flank tumor was lacerated transabdominally in the experimental groups. The three wound sites were randomized to closure of (a) skin; (b) skin and fascia; and (c) skin, fascia, and peritoneum. The abdominal wounds were harvested en bloc on postoperative day 7.

RESULTS

Histologic comparison of the port sites in the pneumoperitoneum and no-pneumoperitoneum groups did not demonstrate a statistically significant difference in tumor implantation for any of the closure methods. Evaluation of the closure techniques showed no statistical difference between the pneumoperitoneum group and the no-pneumoperitoneum group in the incidence of port site tumor implantation. Within the no-pneumoperitoneum group, there was a significant increase (p = 0.03) in tumor implantation with skin closure alone vs all three layers. Additionally, when we compared all groups by closure technique, the rate of tumor implantation was found to be significantly higher (p = 0.01) for skin closure alone vs closure of all three layers.

CONCLUSIONS

This study suggests that closure technique may influence the rate of port site tumor implantation. The use of a CO2 pneumoperitoneum did not alter the incidence of port site tumor implantation at 7 days postoperatively.

Cirrhosis is not a contraindication to laparoscopic surgery

BACKGROUND

Cirrhosis of the liver contributes significantly to morbidity and mortality in abdominal surgery. The proven benefits of laparoscopy seem especially applicable to patients with this complex disease. This study evaluates the safety and efficacy of laparoscopic procedures in a series of consecutively treated patients with biopsy-proven cirrhosis.

METHODS

The medical records of all patients with biopsy-proven cirrhosis undergoing laparoscopic surgery at the authors' medical center between January 2000 and December 2003 were retrospectively reviewed.

RESULTS

A total of 50 patients (27 men and 23 women) underwent 52 laparoscopic procedures. Among these 50 patients were 39 patients with Child-Pugh classification A cirrhosis, 10 with classification B, and 1 with classification C, who underwent a variety of laparoscopic procedures including cholecystectomy (n = 22), splenectomy (n = 18), colectomy (n = 4), diagnostic laparoscopy (n = 3), ventral hernia repair (n = 1), Nissen fundoplication (n = 1), Heller myotomy (n = 1), Roux-en-Y gastric bypass (n = 1), and radical nephrectomy (n = 1). There were two conversions (4%) to an open procedure. The mean operative time was 155 min. Estimated blood loss averaged 124 ml for all procedures, and 20 patients (40%) required perioperative transfusion of blood products. One patient required a single blood transfusion postoperatively because of anemia. No one experienced hepatic decompensation. Overall morbidity was 16%. There were no deaths. The mean length of hospitalization was 3 days.

CONCLUSIONS

Although technically challenging because portal hypertension, varices, and thrombocytopenia frequently coexist, basic and advanced laparoscopic procedures are safe for patients with mild to moderate cirrhosis of the liver.

The laparoscopic repair of suprapubic ventral hernias

BACKGROUND

The complexity of dissection and the close proximity of the hernia to bony, vascular, nerve, and urinary structures make the laparoscopic repair of suprapubic hernias (LRSPH) a formidable operation. We performed a prospective evaluation of the outcomes of patients undergoing LRSPH.

METHODS

The study population comprised 36 patients undergoing LRSPH from July 1996 to January 2004. Patient demographics, hernia sizes, mesh types and sizes, perioperative outcomes, and recurrences were documented. After our early experience with this operation, the repair evolved to include transabdominal suture fixation to the pubic bone, Cooper's ligament, and above the iliopubic tract.

RESULTS

There were 26 women and 10 men. They had a mean age of 55.9 years (range, 33-76) and a mean body mass index (BMI) of 31.0 kg/m2 (range, 22-67). Twenty-two (61%) of the repairs were for recurrent hernias, with an average of 2.3 previously failed open repairs each (range, 1-11). The mean hernia size was 191.4 cm2 (range, 20-768), and the average mesh size was 481.4 cm2 (range, 193-1,428). All repairs were performed with expanded polytetrafluoroethylene (ePTFE) mesh. Mean operating time was 178.7 min (range, 95-290). Mean blood loss was 40 cc (range, 20-100). One patient undergoing her fifth repair required conversion due to adhesions to a polypropylene mesh. Hospital stay averaged 2.4 days (range, 1-7). Mean follow-up was 21.1 months (range, 1-70). Complications (16.6%) included deep venous thrombosis (n = 1), prolonged pain for >6 weeks (n = 1), trocar site cellulitis (n = 1), ileus (n = 1), prolonged seroma (n = 1), and Clostridium difficile colitis (n = 1). Hernias recurred in two of our first nine patients, for an overall recurrence rate of 5.5%. Since we began using the technique of applying multiple sutures directly to the pubis and Cooper's ligament (in the subsequent 27 patients), no recurrences have been documented.

CONCLUSIONS

Although technically demanding and time-consuming, the LRSPH is safe and technically feasible. Moreover, it results in a low recurrence rate and is applicable to large or multiply recurrent hernias. Transabdominal suture fixation to the bony and ligamentous structures produces a more durable hernia repair.

The susceptibility of prosthetic biomaterials to infection

BACKGROUND

Despite the use of a sterile technique and the administration of prophylactic antibiotics during surgical procedures, mesh infection continues to complicate the use of biomaterials. The purpose of this study was to compare the susceptibility to infection of prosthetic biomaterials in a live-animal model.

METHODS

The following seven prosthetic mesh biomaterials were used in this study. Expanded polytetrafluoroethylene (ePTFE) with silver/chlorhexidine (DM+), ePTFE (DM), porcine intestinal submucosa (S), polypropylene (M), ePTFE/polypropylene (X), hyaluronate/carboxymethylcellulose/polypropylene (SM), and human acellular dermal matrix (A). Lewis rats (n = 108) underwent creation of a single ventral hernia; 105 of them were repaired with a different mesh (2-cm2 piece). Twelve pieces of each mesh were inoculated at the time of hernia repair with 10(8) Staphylococcus aureus (n = 84). Three pieces of each mesh were placed without bacterial inoculation (n = 21). In three animals, no mesh was placed; instead, the peritoneum of the hernia defect was inoculated (n = 3). After 5 days, the animals were killed and the mesh was explanted (peritoneum for the nonmesh control). The mesh was vortex-washed and incubated in tryptic soy broth. Bacterial counts were determined using serial dilutions and spot plates and quantified in colony-forming units (CFU) per square centimeter of mesh present in the vortex wash fluid (wash count) and the soy broth (broth count). Data are presented as the mean log(10), with analysis of variance (ANOVA) and Tukey's test used to determine significance (p < 0.05).

RESULTS

The DM+ material had no detectable live bacteria in the wash or broth counts in 10 of 12 tested samples (p = 0.05). Of the samples that showed bacterial growth, the peritoneum control group had a lower wash count than A (p = 0.05) and the lowest broth count of all the materials except for DM+ (p = 0.05). In addition, SM had a significantly lower wash count than A (p = 0.05), with no broth count difference. In regard to wash and broth counts, DM, M, X, SM, S, and A were no different (p = NS).

CONCLUSIONS

The DM+ material was the least susceptible to infection. Impregnation with silver/chlorhexidine killed the inoculated bacteria, preventing their proliferation on the mesh surface. Other than DM+, native peritoneal tissue appears to be the least susceptible to infection. Silver/chlorhexidine appears to be an effective bactericidal agent for use with mesh biomaterials.

A novel technique of lumbar hernia repair using bone anchor fixation

Lumbar hernias are difficult to repair due to their proximity to bone and inadequate surrounding tissue to buttress the repair. We analyzed the outcome of patients undergoing a novel retromuscular lumbar hernia repair technique. The repair was performed in ten patients using a polypropylene or polytetrafluoroethylene mesh placed in an extraperitoneal, retromuscular position with at least 5 cm overlap of the hernia defect. The mesh was fixed with circumferential, transfascial, permanent sutures and inferiorly fixed to the iliac crest by suture bone anchors. Five hernias were recurrent, and five were incarcerated; seven were incisional hernias, and three were posttraumatic. Back and abdominal pain was the most common presenting symptom. Mean hernia size was 227 cm(2) (60-504) with a mesh size of 620 cm(2) (224-936). Mean operative time was 181 min (120-269), with a mean blood loss of 128 ml (50-200). Mean length of stay was 5.2 days (2-10), and morphine equivalent requirement was 200 mg (47-460). There were no postoperative complications or deaths. After a mean follow-up of 40 months (3-99) there have been no recurrences. Our sublay repair of lumbar hernias with permanent suture fixation is safe and to date has resulted in no recurrences. Suture bone anchors ensure secure fixation of the mesh to the iliac crest and may eliminate a common area of recurrence.

Gastrointestinal stromal tumors of the stomach

Gastrointestinal stromal tumors (GIST) comprise a rare group of neoplasms of unpredictable malignant potential with an annual incidence of 4/million persons. The stomach is the most common site of occurrence in the gastrointestinal tract. A combination of prognostic factors (patient age, histologic grade, mitotic rate, tumor size, and DNA analysis) have been utilized to predict their biologic behavior. Lymphatic spread of gastrointestinal stromal tumors is uncommon therefore a formal lymph node dissection is not standard surgical management. Consequently, complete surgical resection of the primary tumor is the most definitive treatment. An increasing number of cases have been reported utilizing a combination of laparoscopic and endoscopic techniques to resect these tumors. The manuscript will characterize the biologic behavior of gastrointestinal stromal tumors of the stomach, discuss the preoperative evaluation and minimally invasive surgical management of these patients, and review recent, encouraging adjuvant treatment strategies.

Plastic wound protectors do not affect wound infection rates following laparoscopic-assisted colectomy

BACKGROUND

Wound protectors are plastic sheaths that can be used to line a wound during surgery. Wound protectors can facilitate retraction of an incision without the need for other mechanical retractors and have been proposed as deterrents to wound infection. The purpose of this study was to define the ability of wound protectors to reduce the rate of infection when used in laparoscopic-assisted colectomy.

METHODS

We completed a retrospective review of the medical records of patients undergoing nonemergent laparoscopic-assisted colectomy between February 1999 and November 2002. All completely laparoscopic cases were excluded. The wound protector, when used, was applied to the extraction incision during the externalized portion of the procedure (colon and mesentery transection, anastomosis). Outcomes for patients with and without the use of a wound protector were compared.

RESULTS

A total of 141 patients underwent laparoscopic-assisted colectomy (98 for benign/malignant tumors, 35 for diverticular disease, and eight for Crohn's disease). There were no differences between the wound protector group ( n = 84) and the no wound protector group ( n = 57) with respect to mean age (55 vs 58 years), average body mass index (27 vs 29 kg/m2), gender, indication for surgery, comorbidities, antibiotics used, or mean operative time (185 vs 173 min). Nine patients in the wound protector group and eight in the no wound protector group developed a wound infection at the colon extraction site ( p = 0.42). Patients undergoing resection for Crohn's disease or diverticulitis had a higher infection rate (18.6%) than patients undergoing resection for polyps or cancer (9.2%; p < 0.05). No wound recurrence of cancer was observed in either group at a mean follow-up of 23 months (range, 3-48).

CONCLUSIONS

The wound protector, although useful for mechanical retraction of small wounds, does not significantly diminish the rate of wound infection at the bowel resection/anastomotic site. Patients undergoing elective resection for inflammatory processes have higher infection rates than patients undergoing laparoscopic-assisted colectomy for polyps or cancer.

Laparoscopic versus open nephrectomy in 210 consecutive patients: Outcomes, cost, and changes in practice patterns

BACKGROUND

Initially slow to gain widespread acceptance within the urological community, laparoscopic nephrectomy is now becoming the standard of care in many centers. Our institution has seen a dramatic transformation in practice patterns and patient outcomes in the 2 years following the introduction of laparoscopic nephrectomy. We compare the experience with laparoscopic and open nephrectomy within a single medical center.

METHODS

Data were collected for all patients undergoing elective nephrectomy (live donor, radical, simple, partial, and nephroureterectomy) between August 1998 and September 2002. Data were analyzed by Wilcoxon rank sum, chi-square, and Fisher's exact test. A p-value <0.05 was considered significant.

RESULTS

Of the patients, 92 underwent open nephrectomy, and 118 were treated laparoscopically (87 hand-assisted laparoscopic nephrectomy, 31 totally laparoscopic). There was one conversion (0.8%). Patient demographics and indications for surgery were equivalent for both groups. Mean operative time for laparoscopic nephrectomy (230 min) was longer than for open (187 min, p = 0.0001). Blood loss (97 ml vs 216 ml, p = 0.0001), length of stay (3.9 days vs 5.9 days, p = 0.0001), perioperative morbidity (14% vs 31%, p = 0.01), and wound complications (6.8% vs 27.1%, p = 0.0001) were all significantly less for laparoscopic nephrectomy. For live donors, time to convalescence was less (12 days vs 33 days, p = 0.02), but hospital charges were more for patients treated laparoscopically (19,007 dollars vs 13,581 dollars, p = 0.0001).

CONCLUSIONS

Laparoscopic nephrectomy results in less blood loss, fewer hospital days, fewer complications, and more rapid recovery than open surgery. We believe that these benefits outweigh the higher hospital charges associated with the laparoscopic approach.

Comparison of ultrasonic energy, bipolar thermal energy, and vascular clips for the hemostasis of small-, medium-, and large-sized arteries

BACKGROUND

Advanced laparoscopic procedures have necessitated the development of new technology for vascular control. Suture ligation can be time-consuming and cumbersome during laparoscopic dissection. Titanium clips have been used for hemostasis, and recently plastic clips and energy sources such as ultrasonic coagulating shears and bipolar thermal energy devices have become popular. The purpose of this study was to compare the bursting pressure of arteries sealed with ultrasonic coagulating shears (UCS), electrothermal bipolar vessel sealer (EBVS), titanium laparoscopic clips (LCs), and plastic laparoscopic clips (PCs). In addition, the spread of thermal injury from the UCS and the EBVS was compared.

METHODS

Arteries in three size groups (2-3, 4-5 and 6-7 mm) were harvested from freshly euthanized pigs. Each of the four devices was used to seal 16 specimens from each size group for burst testing. A 5-Fr catheter was placed into the open end of the specimen and secured with a purse-string suture. The catheter was connected to a pressure monitor and saline was infused until there was leakage from the sealed end. This defined the bursting pressure in mmHg. The ultrasonic shears and bipolar thermal device were used to seal an additional 8 vessels in each size group, which were sent for histologic examination. These were examined with hematoxylin and eosin stains, and the extent of thermal injury, defined by coagulation necrosis, was measured in millimeters. Analysis of variance was performed and, where appropriate, a Tukey's test was also performed.

RESULTS

The EBVS's mean burst pressure was statistically higher than that of the UCS at 4 or 5 mm (601 vs 205 mmHg) and 6 or 7 mm (442 vs 175 mmHg). EBVS had higher burst pressures for the 4 or 5-mm group (601 mmHg) and 6 or 7-mm group (442 mmHg) compared with its pressure at 2 or 3 mm (128 mmHg) ( p = 0.0001). The burst pressures of the UCS and EBVS at 2 or 3 mm were not significantly different. Both clips were statistically stronger than the thermal devices except at 4 or 5 mm, in which case the EBVS was as strong as the LC (601 vs 593 mmHg). The PC and LC were similar except at 4 or 5 mm, where the PC was superior (854 vs 593 mmHg). The PC burst pressure for 4 or 5 mm (854 mmHg) was statistically higher than that for vessels 2 or 3 mm (737 mmHg) but not different from the 6 or 7 mm pressure (767 mmHg). Thermal spread was not statistically different when comparing EBVS and UCS at any size (EBVS mean = 2.57 mm vs UCS mean = 2.18 mm).

CONCLUSIONS

Both the PC and LC secured all vessel sizes to well above physiologic levels. The EBVS can be used confidently in vessels up to 7 mm. There is no difference in the thermal spread of the LigaSure vessel sealer and the UCS.

Determination of intact splenic weight based on morcellated weight

BACKGROUND

Comparisons of splenic size based on splenic weight are difficult after laparoscopic splenectomy, which results in a morcellated specimen. We report the results of a direct comparison between morcellated and intact splenic weights.

METHODS

Porcine spleens were harvested via a midline laparotomy, and an intact splenic weight was obtained, which served as the control. The spleen then was placed into an impermeable retrieval bag and returned to the peritoneal cavity. A separate 10-mm incision was made and the spleen mechanically morcellated with a uterine forceps. This design most faithfully recreates the morcellation process during laparoscopic splenectomy in humans. The aggregate weight of the fragments was compared with intact splenic weight.

RESULTS

Intact and morcellated weights were obtained from 58 porcine spleens. The mean intact splenic weight was 145 g, and the mean morcellated weight was 78 g. For a given morcellated weight achieved at laparoscopic splenectomy, an estimated intact weight can be determined by the following formula: intact weight (g) = morcellated weight (g) x 1.34 + 45.

CONCLUSIONS

On the basis of our calculations, a normal spleen weighing 150 g would have a mean morcellated weight of 78 g, and splenomegaly (intact spleen weighing 250 g or more) would be defined by a morcellated weight exceeding 153 g.

Laparoscopic repair of traumatic diaphragmatic injuries

BACKGROUND

The purpose of this study was to evaluate the feasibility and limitations of laparoscopic repair of traumatic diaphragmatic injuries.

METHODS

Laparoscopic repair of an acute traumatic diaphragmatic laceration or chronic traumatic diaphragmatic hernia was attempted in 17 patients between January 1997 and January 2001. The patients in the study included 13 men and 4 women with a mean age of 33.2 years (range, 15-63 years). Nine patients had a blunt injury, and eight patients had a penetrating injury. Laparoscopic repair was attempted for eight patients during their hospitalization for the traumatic injury (mean, 2.3 days; range, 0-6 days) and for ten patients with a chronic diaphragmatic hernia (mean, 89 months; range, 5-420 months). The chronic diaphragmatic hernias-presented with abdominal pain (9/9), or vomiting (3/9).

RESULTS

Thirteen traumatic diaphragmatic injuries were repaired laparoscopically, and four (2 acute and 2 chronic) required conversion. Among the laparoscopically repaired diaphragmatic injuries, three defects (chronic) were repaired using expanded polytetrafluoroethylene (ePTFE), and nine were repaired primarily. The mean length of the diaphragmatic defects was 4.6 cm (range, 1.5-12 cm). The mean operative time was 134.7 min (range, 55-200 min). The mean estimated blood loss was 108.5 ml (range, 30-500 ml), and the postoperative length of stay was 4.4 days (range, 1-12 days). There were no intraoperative complications, but three patients developed pulmonary complications (atelectasis/pneumonia). Follow-up evaluation was available for 11 patients. There were no documented recurrences after a mean follow-up period of 7.9 months (range, 1 week to 24 months). Conversion resulted from a reluctance or inability to perform laparoscopic suture of transverse diaphragmatic lacerations longer than 10 cm anterior to the esophageal hiatus and adjacent to the pericardium (n = 2) or communicating with the esophageal hiatus (n = 2). One patient also required spleneotomy for an unrecognized splenic laceration that had occurred at the time of the original trauma. The four patients undergoing laparotomy had a mean postoperative discharge date of 8.7 days (range, 6-14 days).

CONCLUSIONS

Laparoscopy is an alternative approach to repairing acute traumatic diaphragmatic lacerations and chronic traumatic diaphragmatic hernias. Large traumatic diaphragmatic injuries adjacent to or including the esophageal hiatus are best approached via laparotomy.

Prospective randomized evaluation of surgical resident proficiency with laparoscopic suturing after course instruction

BACKGROUND

Laparoscopic suturing is required to develop competency in advanced laparoscopy.

METHODS

Manuals detailing laparoscopic suturing were give to 17 Surgery residents. One week later they performed a suture on a training model. Time (s), accuracy (mm), and knot strength (lb) were recorded. The residents were blindly randomized to intervention (n = 9) and control (n = 8) groups. The intervention residents attended a 60-min course with lecture, video, and individual proctoring. Two weeks later they performed a stitch with standard laparoscopic instruments and a stitch with a suturing assist device. Statistical analysis included a Wilcoxon rank-sum test.

RESULTS

The intervention residents decreased their suturing time from the first to the second stitich (732.4-257.6s), the control and residents decreased their time from 500.2 s to 421.8 s. The time required to perform the second stitch showed no significant difference between the two groups (p = 0.46), but the difference in reduced time between the first and second stitch was significant (p = 0.001). Using the suturing assist device for the third suture, the intervention and control groups both decreased their times significantly. The control residents performed almost as quickly as the intervention residents with the suturing; device (p = 0.11). Accuracy and knot strength were not different in any test.

CONCLUSIONS

Residents can improve suturing skill with a short didactic course and individual proctoring. A suturing assist device decreases time required by inexperienced surgeons to device perform an intracorporeal tie.

Outcomes for Laparoscopic Bilateral Adrenalectomy

BACKGROUND AND PURPOSE

Laparoscopic adrenalectomy has become the preferred surgical approach to manage adrenal disorders. Bilateral adrenalectomy is performed for diseases that are unresponsive to medical management and, frequently, for neoplastic disease. The aim of this study was to review our experience with laparoscopic bilateral adrenalectomy and to evaluate its safety, efficacy, and outcomes.

PATIENTS AND METHODS

Between July 1996 and May 2001, five male and two female patients with a mean age of 46 years (range 15-69 years) presented for bilateral adrenalectomy (pheochromocytoma [N = 3], Cushing's disease [N = 3], and metastatic cancer [N = 1]). All procedures were performed using a lateral transperitoneal approach. One gland was excised, the patient was repositioned to the opposite lateral decubitus position, and the remaining gland was removed.

RESULTS

Laparoscopic bilateral adrenalectomy was completed in all seven patients. The mean tumor/gland size on the right was 5.0 cm (range 3.1-7.0 cm) and on the left was 5.6 cm (range 3.6-7.0 cm). The mean operative time was 308 minutes (range 190-430 minutes), and the mean estimated blood loss was 138 mL (range 30-300 mL). One patient with a pheochromocytoma experienced intraoperative hypertension necessitating treatment. There were no postoperative complications. The mean postoperative hospital stay was 5.1 days (range 3-9 days). All patients have been treated postoperatively with daily hydrocortisone and fludrocortisone replacement. After a mean follow-up of 33 months (range 2-45 months), six patients are alive. The patient undergoing bilateral adrenalectomy for metastatic lung cancer died from recurrent disease 13 months after resection.

CONCLUSION

Laparoscopic bilateral adrenalectomy is safe and effective. Patients are discharged postoperatively in a relatively short time with few complications. Appropriate steroid replacement and close follow-up allows these patients to return to self-reliance.