Using video-based assessment (VBA) to document fellow improvement in safely completing the jejunojejunostomy portion of laparoscopic Roux-en-Y gastric bypass (RYGB) surgery

BACKGROUND

Surgical assessment instruments are used for formative and summative trainee evaluations. To characterize the features of existing instruments and a novel 12-item objective, procedure-specific assessment tool for Roux-en-Y Gastric Bypass (RYGB-OPSA), we evaluated the progress of a single surgical fellow over 17 consecutive surgeries.

METHODS

Seventeen consecutive RYGB videos completed between 8/2021 and 1/2022 by an academic hospital surgical fellow were de-identified and assessed by four board-certified bariatric surgeons using Global Operative Assessment of Laparoscopic Skills (GOALS), General Assessment of Surgical Skill (GASS), and RYGB-OPSA which includes the reflection of transverse colon, identification of ligament of Treitz, biliopancreatic and Roux limbs orientation, jejunal division point selection, stapler use, mesentery division, bleeding control, jejunojejunostomy (JJ) anastomotic site selection, apposition of JJ anastomotic site, JJ creation, common enterotomy closure of JJ, and integrity of anastomosis. The GASS measured economy of motion, tissue handling, appreciating operative anatomy, bimanual dexterity, and achievement of hemostasis. RYGB-OPSA and GASS items were scored "poor-unsafe," "acceptable-safe," or "good-safe." Change in performance was measured by linear trendline slope.

RESULTS

Over the course of 17 procedures, significant improvement was demonstrated by three GOALS items, GOALS overall score, GASS bimanual dexterity, and three RYGB-OPSA tasks: JJ creation, jejunal division point selection, and stapler use. Achievement of hemostasis declined but never rated "poor-unsafe." Overall RYGB-OPSA and GOALS trendlines documented significant increase across the 17 procedures.

CONCLUSION

This examination of a bariatric surgery fellow's operative training experience as measured by three surgical assessment instruments demonstrated anticipated improvements in general skills and safe completion of procedure-specific tasks. Effective surgical assessment instruments have enough sensitivity to show improvement to enable meaningful trainee feedback (low-stakes assessments) as well as the ability to determine safe surgical practice to enable promotion to greater autonomous practice.

Global assessment of surgical skills (GASS): validation of a new instrument to measure global technical safety in surgical procedures

BACKGROUND

Broad implementation of the American Board of Surgery's entrustable professional activities initiative will require assessment instruments that are reliable and easy to use. Existing assessment instruments of general laparoscopic surgical skills have limited reliability, efficiency, and validity across the spectrum of formative (low-stakes) and summative (high-stakes) assessments. A novel six-item global assessment of surgical skills (GASS) instrument was developed and evaluated with a focus upon safe versus unsafe surgical practice scoring rubric.

METHODS

The GASS was developed by iterative engagement with expert laparoscopic surgeons and includes six items (economy of motion, tissue handling, appreciating operative anatomy, bimanual dexterity, achievement of hemostasis, overall performance) with a uniform three-point scoring rubric ("poor-unsafe", "adequate-safe", "good-safe"). To test inter-rater reliability, a cross-sectional study of four bariatric surgeons with experience ranging from 4 to 28 years applied the GASS and the global operative assessment of laparoscopic skills (GOALS) to 30 consecutive Roux-en-Y gastric bypass procedure operative videos. Inter-rater reliability was assessed for a simplified dichotomous "safe" versus "unsafe" scoring rubric using Gwet's AC2.

RESULTS

The GASS inter-rater reliability was very high across all six domains (0.88-1.00). The GASS performed comparably to the GOALS inter-rater reliability scores (0.96-1.00). The economy of motion and bimanual dexterity items had the highest percentage of unsafe ratings (9.2% and 5.8%, respectively).

CONCLUSION

The GASS, a novel six-item instrument of general laparoscopic surgical skills, was designed with a simple scoring rubric (poor-safe, adequate-safe, good-safe) to minimize rater burden and focus feedback to trainees and promotion evaluations on safe surgical performance. Initial evaluation of the GASS is promising, demonstrating high inter-rater reliability. Future research will seek to assess the GASS against a broader spectrum of laparoscopic procedures.

Fighting the obesity pandemic during the COVID-19 pandemic

Background

The COVID-19 pandemic created delays in surgical care. The population with obesity has a high risk of death from COVID-19. Prior literature shows the most effective way to combat obesity is by weight loss surgery. At different times throughout the COVID-19 pandemic, elective inpatient surgeries have been halted due to bed availability. Recognizing that major complications following bariatric surgery are extremely low (bleeding 0–4%, anastomotic leaks 0.8%), we felt outpatient bariatric surgery would be safe for low-risk patients. Complications such as DVT, PE, infection, and anastomotic leaks typically present after 7 days postoperatively, well outside the usual length of stay. Bleeding events, severe postoperative nausea, and dehydration typically occur in the first few days postoperatively. We designed a pathway focused on detecting and preventing these early post-op complications to allow safe outpatient bariatric surgery.

Methods

We used a preoperative evaluation tool to risk stratify bariatric patients. During a 16-month period, 89 patients were identified as low risk for outpatient surgery. We designed a postoperative protocol that included IV hydration and PO intake goals to meet a safe discharge. We sent patients home with a pulse oximeter and had them self-monitor their pulse and oxygen saturation. We called all patients at 10 pm for a postoperative assessment and report of their vitals. Patients returned to clinic the following day and were seen by a provider, received IV hydration, and labs were drawn. RESULTS: 80 of 89 patients (89.8%) were successfully discharged on POD 0. 3 patients were readmitted within 30 days. We had zero deaths in our study cohort and no morbidity that would have been prevented with postoperative admission.

Conclusion

We demonstrate that by identifying low-risk patients for outpatient bariatric surgery and by implementing remote monitoring of vitals early outpatient follow-up, we were able to safely perform outpatient bariatric surgery.

Graphical abstract

Prospective, multicenter study of P4HB (Phasix™) mesh for hernia repair in cohort at risk for complications: 3-Year follow-up

BACKGROUND

This study represents a prospective, multicenter, open-label study to assess the safety, performance, and outcomes of poly-4-hydroxybutyrate (P4HB, Phasix™) mesh for primary ventral, primary incisional, or multiply-recurrent hernia in subjects at risk for complications. This study reports 3-year clinical outcomes.

MATERIALS AND METHODS

P4HB mesh was implanted in 121 patients via retrorectus or onlay technique. Physical exam and/or quality of life surveys were completed at 1, 3, 6,12, 18, 24, and 36 months, with 5-year (60-month) follow-up ongoing.

RESULTS

A total of n = 121 patients were implanted with P4HB mesh (n = 75 (62%) female) with a mean age of 54.7 ± 12.0 years and mean BMI of 32.2 ± 4.5 kg/m2 (±standard deviation). Comorbidities included: obesity (78.5%), active smokers (23.1%), COPD (28.1%), diabetes mellitus (33.1%), immunosuppression (8.3%), coronary artery disease (21.5%), chronic corticosteroid use (5.0%), hypo-albuminemia (2.5%), advanced age (5.0%), and renal insufficiency (0.8%). Hernias were repaired via retrorectus (n = 45, 37.2% with myofascial release (MR) or n = 43, 35.5% without MR), onlay (n = 8, 6.6% with MR or n = 24, 19.8% without MR), or not reported (n = 1, 0.8%). 82 patients (67.8%) completed 36-month follow-up. 17 patients (17.9% ± 0.4%) experienced hernia recurrence at 3 years, with n = 9 in the retrorectus group and n = 8 in the onlay group. SSI (n = 11) occurred in 9.3% ± 0.03% of patients.

CONCLUSIONS

Long-term outcomes following ventral hernia repair with P4HB mesh demonstrate low recurrence rates at 3-year (36-month) postoperative time frame with no patients developing late mesh complications or requiring mesh removal. 5-year (60-month) follow-up is ongoing.

Roux-en-Y gastric bypass surgery alters serum metabolites and fatty acids in patients with morbid obesity

AIM

Bariatric surgery induces significant weight loss, increases insulin sensitivity, and reduces mortality, but the underlying mechanisms are not clear. It was hypothesized that Roux-en-Y gastric bypass (RYGB) surgery improves metabolic profile along with weight loss. The objective of this pilot study was to evaluate changes in serum metabolites and fatty acids (FA) at 2 weeks and 6 months after RYGB.

MATERIALS AND METHODS

Serum samples were collected pre-surgery, at 2 weeks and 6 months post-surgery from 20 patients undergoing RYGB surgery. Serum non-esterified free FA (NEFA) were measured. Serum metabolites and FA were measured using nuclear magnetic resonance spectroscopy and improved direct fatty acid methyl ester synthesis and the gas chromatography/mass spectrometry method, respectively, in subjects who completed follow-up at 6 months (n = 8).

RESULTS

Mean (standard deviation) percent total weight loss was 6.70% (1.7) and 24.91% (6.63) at 2 weeks (n = 15) and 6 months (n = 8) post-surgery, respectively. NEFA were significantly reduced at 6 months post-surgery (P = 0.001, n = 8). Serum branched chain amino acids, 2-aminobutyrate, butyrate, 2-hydroxybutyrate, 3-hydroxybutyrate, acetone, 2-methylglutarate, and 2-oxoisocaproate were significantly reduced, while serum alanine, glycine, pyruvate, and taurine were significantly elevated at 6 months post-surgery compared with pre-surgery (n = 8, P < 0.05). Also, serum FA C10:0, C13:0, C14:0, C15:0, and C18:0 increased significantly (n = 8, P < 0.05) by 6 months post-surgery.

CONCLUSIONS

Changes in serum metabolites and FA at 6 months post-RYGB surgery in this pilot study with limited number of participants are suggestive of metabolic improvement; larger studies are warranted for confirmation.

Optical design of an in vivo laparoscopic lighting system

This paper proposes an in vivo laparoscopic lighting system design to address the illumination issues, namely poor lighting uniformity and low optical efficiency, existing in the state-of-the-art in vivo laparoscopic cameras. The transformable design of the laparoscopic lighting system is capable of carrying purposefully designed freeform optical lenses for achieving lighting performance with high illuminance uniformity and high optical efficiency in a desired target region. To design freeform optical lenses for extended light sources such as LEDs with Lambertian light intensity distributions, we present an effective and complete freeform optical design method. The procedures include (1) ray map computation by numerically solving a standard Monge-Ampere equation; (2) initial freeform optical surface construction by using Snell's law and a lens volume restriction; (3) correction of surface normal vectors due to accumulated errors from the initially constructed surfaces; and (4) feedback modification of the solution to deal with degraded illuminance uniformity caused by the extended sizes of the LEDs. We employed an optical design software package to evaluate the performance of our laparoscopic lighting system design. The simulation results show that our design achieves greater than 95% illuminance uniformity and greater than 89% optical efficiency (considering Fresnel losses) for illuminating the target surgical region.

Hardware design for a cable-free fully insertable wireless laparoscopic robotic camera

The field of insertable laparoscopic robotic camera is gaining increasing attentions from researchers, surgeons, and also patients. Although many insertable laparoscope prototypes have been introduced, few of them get rid of the encumbrance tethering cable. In this paper, we proposed a hardware architecture for a magnetic actuated robotic surgical (MARS) camera, which facilitates a cable-free fully insertable laparoscopic surgical robotic camera with adequate in-vivo mobility. Modular design and preliminary test of on-board functional payloads have shown feasibility of a cable-free insertable wireless laparoscopic surgical camera based on off-the-shelf electronics and industrial wireless standards operating in ISM frequency bands at 2.4GHz. Potential improvements for laparoscopic surgery benefited from this hardware architecture include more dexterous in-vivo camera mobility and intuitive closed-loop robotic camera control.

Laparoscopic appendectomy--is it worth the cost? Trend analysis in the US from 2000 to 2005

BACKGROUND

Although laparoscopic appendectomy is widely used for treatment of appendicitis, it is still unclear if it is superior to the open approach.

STUDY DESIGN

From the Nationwide Inpatient Sample 2000 to 2005, hospitalizations with the primary ICD-9 procedure code of laparoscopic (LA) and open appendectomy (OA) were included in this study. Outcomes of length of stay, costs, and complications were assessed by stratified analysis for uncomplicated and complicated appendicitis (perforation or abscess). Regression methods were used to adjust for covariates and to detect trends. Costs were rescaled using the hospital and related services portion of the Medical Consumer Price Index.

RESULTS

Between 2000 and 2005, 132,663 (56.3%) patients underwent OA and 102,810 (43.7%) had LA. Frequency of LA increased from 32.2% to 58.0% (p < 0.001); conversion rates decreased from 9.9% to 6.9% (p < 0.001). Covariate adjusted length of stay for LA was approximately 15% shorter than for OA in both uncomplicated and complicated cases (p < 0.001). Adjusted costs for LA were 22% higher in uncomplicated appendicitis and 9% higher in patients with complicated appendicitis (p < 0.001). Costs and length of stay decreased over time in OA and LA. The risk for a complication was higher in the LA group (p < 0.05, odds ratio=1.07, 95% CI 1.00 to 1.14) with uncomplicated appendicitis.

CONCLUSIONS

LA results in higher costs and increased morbidity for patients with uncomplicated appendicitis. Nevertheless, LA is increasingly used. Patients undergoing LA benefit from a slightly shorter hospital stay. In general, open appendectomy may be the preferred approach for patients with acute appendicitis, with indication for LA in selected subgroups of patients.

Integrated flexible endoscopy training during surgical residency

BACKGROUND

New advances in endoscopic surgery make it imperative that future gastrointestinal surgeons obtain adequate endoscopy skills. An evaluation of the 2001-02 general surgery residency endoscopy experience at the University of Missouri revealed that chief residents were graduating with an average of 43 endoscopic cases. This met American Board of Surgery (ABS) and Accreditation Council for Graduate Medical Education (ACGME) requirements but is inadequate preparation for carrying out advanced endoscopic surgery. Our aim was to determine if endoscopy volume could be improved by dedicating specific staff surgeon time to a gastrointestinal diagnostic center at an affiliated Veterans Administration Hospital.

METHODS

During the academic years 2002-05, two general surgeons who routinely perform endoscopy staffed the gastrointestinal endoscopy center at the Harry S. Truman Hospital two days per week. A minimum of one categorical surgical resident participated during these endoscopy training days while on the Veterans Hospital surgical service. A retrospective observational review of ACGME surgery resident case logs from 2001 to 2005 was conducted to document the changes in resident endoscopy experience. The cases were compiled by postgraduate year (PGY).

RESULTS

Resident endoscopy case volume increased 850% from 2001 to 2005. Graduating residents completed an average of 161 endoscopies. Endoscopic experience was attained at all levels of training: 26, 21, 34, 23, and 26 mean endoscopies/year for PGY-1 to PGY-5, respectively.

CONCLUSIONS

Having specific endoscopy training days at a VA Hospital under the guidance of a dedicated staff surgeon is a successful method to improve surgical resident endoscopy case volume. An integrated endoscopy training curriculum results in early skills acquisition, continued proficiency throughout residency, and is an efficient way to obtain endoscopic skills. In addition, the foundation of flexible endoscopic skill and experience has allowed early integration of surgery residents into research efforts in natural orifice transluminal endoscopic surgery.

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.

Efficacy of laparoscopic appendectomy in appendicitis with peritonitis

Laparoscopic appendectomy (LA) is safe and effective in cases of peritonitis, perforation, and abscess. We investigated our conversion rate and clinical outcomes in this patient population, as well as preoperative factors that predict operative conversion. A retrospective nonrandomized cohort of 92 patients underwent LA for acute appendicitis with peritonitis, perforation, or abscess at our institution between 1997 and 2002. Thirty-six of the 92 were converted to open appendectomy (OA), yielding a conversion rate of 39 per cent. The presence of phlegmon (42%), nonvisualized appendix (44%), technical failures (8%), and bleeding (6%) were reasons for conversion. Preoperative data had no predictive value for conversion. CT scan findings of free fluid, phlegmon, and abscess did not correlate with findings at the time of surgery. Total complication rates were 8.9 per cent in the LA group as compared to 50 per cent in the converted cohort. Postoperative data showed LA patients stayed 3.2 days versus 6.9 days for converted patients (P = 0.01). LA patients had less pneumonia (P = 0.02), intra-abdominal abscess (P = 0.01), ileus (P = 0.01), and readmissions (P = 0.01). LA is safe and effective in patients with appendicitis with peritonitis, perforation, and abscess, resulting in shorter hospital stays and less complication.

Efficacy of Laparoscopic Appendectomy in Appendicitis with Peritonitisa

Laparoscopic appendectomy (LA) is safe and effective in cases of peritonitis, perforation, and abscess. We investigated our conversion rate and clinical outcomes in this patient population, as well as preoperative factors that predict operative conversion. A retrospective nonrandomized cohort of 92 patients underwent LA for acute appendicitis with peritonitis, perforation, or abscess at our institution between 1997 and 2002. Thirty-six of the 92 were converted to open appendectomy (OA), yielding a conversion rate of 39 per cent. The presence of phlegmon (42%), nonvisualized appendix (44%), technical failures (8%), and bleeding (6%) were reasons for conversion. Preoperative data had no predictive value for conversion. CT scan findings of free fluid, phlegmon, and abscess did not correlate with findings at the time of surgery. Total complication rates were 8.9 per cent in the LA group as compared to 50 per cent in the converted cohort. Postoperative data showed LA patients stayed 3.2 days versus 6.9 days for converted patients ( P = 0.01). LA patients had less pneumonia ( P = 0.02), intra-abdominal abscess ( P = 0.01), ileus ( P = 0.01), and readmissions ( P = 0.01). LA is safe and effective in patients with appendicitis with peritonitis, perforation, and abscess, resulting in shorter hospital stays and less complication.

Solid-Pseudopapillary Tumor of the Pancreas: Two Cases in Male Patients

Solid-pseudopapillary tumor (SPT) of the pancreas is a rare lesion with low malignant potential occurring predominantly in young women. This is a report of two cases in young male patients. Clinical data were retrieved retrospectively from a prospective database of patients with pancreatic tumors. The two patients were Caucasian males, ages 34 years (Pt1) and 41 years (Pt2) at the time of diagnosis. Pt1 presented with intermittent epigastric pain, nausea, and vomiting. Computed tomography (CT) scan showed a 9-cm mass involving the pancreatic head. He underwent pancreaticoduodenectomy, with en bloc segmental colectomy due to mesocolon involvement. Pt2 was asymptomatic, diagnosed with abdominal mass by screening ultrasound. He had an 11-cm tumor involving the pancreatic tail encasing the splenic vessels on CT. He underwent distal pancreatectomy with splenectomy en bloc. Pathology in both cases was reviewed by staff pathologists as well as outside consultants. SPT is a rare tumor of the pancreas that is diagnosed primarily in young women. The cases presented here demonstrate SPT of the pancreas in two men. In both cases, the clinical presentation was relatively unremarkable. Both have had benign late postoperative courses, consistent with the low malignant potential of this lesion.

Solid-pseudopapillary tumor of the pancreas: two cases in male patients

Solid-pseudopapillary tumor (SPT) of the pancreas is a rare lesion with low malignant potential occurring predominantly in young women. This is a report of two cases in young male patients. Clinical data were retrieved retrospectively from a prospective database of patients with pancreatic tumors. The two patients were caucasian males, ages 34 years (Pt1) and 41 years (Pt2) at the time of diagnosis. Pt1 presented with intermittent epigastric pain, nausea, and vomiting. Computed tomography (CT) scan showed a 9-cm mass involving the pancreatic head. He underwent pancreaticoduodenectomy, with en bloc segmental colectomy due to mesocolon involvement. Pt2 was asymptomatic, diagnosed with abdominal mass by screening ultrasound. He had an 11-cm tumor involving the pancreatic tail encasing the splenic vessels on CT. He underwent distal pancreatectomy with splenectomy en bloc. Pathology in both cases was reviewed by staff pathologists as well as outside consultants. SPT is a rare tumor of the pancreas that is diagnosed primarily in young women. The cases presented here demonstrate SPT of the pancreas in two men. In both cases, the clinical presentation was relatively unremarkable. Both have had benign late postoperative courses, consistent with the low malignant potential of this lesion.

Parastomal pyoderma gangrenosum: a case report and literature review

Parastomal pyoderma gangrenosum (PPG) is an exceedingly rare disease process most often observed in inflammatory bowel disease patients with an ileostomy. Fewer than 50 cases have been reported in the medical literature. The incidence is 0.6 per cent of patients with ileostomy and inflammatory bowel disease. The rarity of the disease leads to misdiagnosis and mistreatment of the lesion. The intense pain and disruption of ostomy function greatly impair affected individuals beyond the limit of their underlying disease. Current best care practices observed in small study series indicate long-term intensive medical therapy aimed at systemic disease suppression to optimize PPG wound healing. Our patient had no signs of active Crohn disease at the time of PPG presentation. She was initially treated with minimal wound debridement and intralesional triamcinolone. Finally under the care of an enterostomal/wound care therapist the patient achieved excellent PPG resolution in 6 months.

Parasternal Pyoderma Gangrenosum: A Case Report and Literature Review

Parasternal pyoderma gangrenosum (PPG) is an exceedingly rare disease process most often observed in inflammatory bowel disease patients with an ileostomy. Fewer than 50 cases have been reported in the medical literature. The incidence is 0.6 per cent of patients with ileostomy and inflammatory bowel disease. The rarity of the disease leads to misdiagnosis and mistreatment of the lesion. The intense pain and disruption of ostomy function greatly impair affected individuals beyond the limit of their underlying disease. Current best care practices observed in small study series indicate long-term intensive medical therapy aimed at systemic disease suppression to optimize PPG wound healing. Our patient had no signs of active Crohn disease at the time of PPG presentation. She was initially treated with minimal wound debridement and intralesional triamcinolone. Finally under the care of an enterostomal/wound care therapist the patient achieved excellent PPG resolution in 6 months.

Hand-assisted laparoscopic radical nephrectomy: comparison with transabdominal radical nephrectomy

The purpose of this study was to investigate whether hand-assisted laparoscopic radical nephrectomy (HALN) has benefits over the traditional transabdominal radical nephrectomy. More specifically we focused on the use of the hand-assisted technique as a definitive oncologic procedure for renal cancers. This study is a retrospective nonrandomized study comparing 12 hand-assisted laparoscopic radical nephrectomies with 12 transabdominal radical nephrectomies. All patients included in the study had the preoperative diagnosis of renal mass. HALN population averaged 1.83 +/- 1.64 (mean +/- standard deviation) major comorbidities versus 1.08 +/- 0.8 open (P = 0.032). The HALN OR time averaged 103 +/- 32.8 versus 57 +/- 18.3 minutes open (P = 0.001). The estimated blood loss mean for HALN was 83 versus 318 cm3 open (P = 0.001). Length of stay for HALN was 4.9 +/- 2.2 versus 5.9 +/- 2.9 days (P = 0.35). Days to regular diet was 2.9 +/- 2.3 in HALN versus 3.5 +/- 2.11 open (P = 0.52). Days of intravenous pain medications were 1.8 +/- 0.72 HALN versus 3.0 +/- 1.28 open (P = 0.016). Postoperative complication rates for the two groups were identical: two of 12 (ileus and post-operative bleeding). Tumor size mean was 6.8 +/- 2.99 cm for HALN versus 4.2 +/- 1.29 cm open (P = 0.012). Tumor margins were negative for 12 of 12 in HALN versus 11 of 12 open. Selection bias (selecting ailing patients to the HALN cohort) diminished the statistical significance of our postoperative recovery data. It is likely that a prospectively randomized study with a larger population may prove the hand-assisted approach equal if not superior to the open technique. The use of HALN in patients with renal tumors is an effective alternative to traditional transabdominal radical nephrectomy.

Hand-Assisted Laparoscopic Radical Nephrectomy: Comparison with Transabdominal Radical Nephrectomy

The purpose of this study was to investigate whether hand-assisted laparoscopic radical nephrectomy (HALN) has benefits over the traditional transabdominal radical nephrectomy. More specifically we focused on the use of the hand-assisted technique as a definitive oncologic procedure for renal cancers. This study is a retrospective nonrandomized study comparing 12 hand-assisted laparoscopic radical nephrectomies with 12 transabdominal radical nephrectomies. All patients included in the study had the preoperative diagnosis of renal mass. HALN population averaged 1.83 ± 1.64 (mean ± standard deviation) major comorbidities versus 1.08 ± 0.8 open ( P = 0.032). The HALN OR time averaged 103 ± 32.8 versus 57 ± 18.3 minutes open ( P = 0.001). The estimated blood loss mean for HALN was 83 versus 318 cm3 open ( P = 0.001). Length of stay for HALN was 4.9 ± 2.2 versus 5.9 ± 2.9 days ( P = 0.35). Days to regular diet was 2.9 ± 2.3 in HALN versus 3.5 ± 2.11 open ( P = 0.52). Days of intravenous pain medications were 1.8 ± 0.72 HALN versus 3.0 ± 1.28 open ( P = 0.016). Postoperative complication rates for the two groups were identical: two of 12 (ileus and post-operative bleeding). Tumor size mean was 6.8 ± 2.99 cm for HALN versus 4.2 ± 1.29 cm open ( P = 0.012). Tumor margins were negative for 12 of 12 in HALN versus 11 of 12 open. Selection bias (selecting ailing patients to the HALN cohort) diminished the statistical significance of our postoperative recovery data. It is likely that a prospectively randomized study with a larger population may prove the hand-assisted approach equal if not superior to the open technique. The use of HALN in patients with renal tumors is an effective alternative to traditional transabdominal radical nephrectomy.

Clonogenic analysis reveals reserve stem cells in postnatal mammals: I. Pluripotent mesenchymal stem cells

Clonal populations of lineage-uncommitted pluripotent mesenchymal stem cells have been identified in prenatal avians and rodents. These cells reside in the connective tissue matrices of many organs and tissues. They demonstrate extended capabilities for self-renewal and the ability to differentiate into multiple separate tissues within the mesodermal germ line. This study was designed to determine whether such cells are present in the connective tissues of postnatal mammals. This report describes a cell clone derived by isolation from postnatal rat connective tissues, cryopreservation, extended propagation, and serial dilution clonogenic analysis. In the undifferentiated state, this clone demonstrates a high nuclear-to-cytoplasmic ratio and extended capacity for self-renewal. Subsequent morphological, histochemical, and immunochemical analysis after the induction of differentiation revealed phenotypic markers characteristic of multiple cell types of mesodermal origin, such as skeletal muscle, smooth muscle, fat cells, cartilage, and bone. These results indicate that this clone consists of pluripotent mesenchymal stem cells. This report demonstrates that clonal populations of reserve stem cells are present in mammals after birth. Potential roles for such cells in the maintenance, repair, and regeneration of mesodermal tissues are discussed.