Sanjeev Dutta

Early experience with single incision laparoscopic surgery: eliminating the scar from abdominal operations

PURPOSE Single incision laproscopic surgery (SILS) involves performing abdominal operations with laparoscopic instruments placed through a single, small umbilical incision. The primary goal is to avoid visible scarring. This is the first report of SILS cholecystectomy in children and the first report in the literature of SILS splenectomy. METHODS A retrospective chart review was performed in 20 consecutive inpatient SILS procedures (13 males, 7 females; ages 2-17 years) from May to December 2008. Outcome measures included need for conversion, operative time, time to oral analgesia, length of hospitalization, cosmetic outcome, and complications. RESULTS There were 4 total splenectomies, 3 cholecystectomies, 2 combined splenectomy/cholecystectomies, and 11 appendectomies performed. All procedures were completed successfully without need for conversion to standard laparoscopy or open surgery. Mean operative time was 90 minutes for splenectomy, 68 minutes for cholecystectomy, 165 minutes for combined splenectomy/cholecystectomy, and 33 minutes for appendectomy. Mean hospital stay was 1 day for appendectomy, 1 day for cholecystectomy, and 2.5 days for splenectomy. One splenectomy patient received 1 U packed red blood cell transfusion. All appendectomy patients were converted to oral analgesia within 24 hours and splenectomy patients within 48 hours. All families were very pleased with the cosmetic outcome. CONCLUSION Single incision laparoscopic surgery is feasible for a variety of pediatric general surgical conditions, allowing for scarless abdominal operations. This early experience suggests that outcomes are comparable to standard laparoscopic surgery but with improved cosmesis, however, a larger series is necessary to confirm these findings and to determine if there are any benefits in pain or recovery. Surgeons performing SILS should have a firm foundation of advanced minimal access surgical skills and a cautious, gradated approach to attempting the various procedures. Technological refinements will further enable SILS.

A comparison of laparoscopic and robotic assisted suturing performance by experts and novices.

BACKGROUND Surgical robotics has been promoted as an enabling technology. This study tests the hypothesis that use of the robotic surgical system can significantly improve technical ability by comparing the performance of both experts and novices on a complex laparoscopic task and a robotically assisted task. METHODS Laparoscopic experts (LE) with substantial laparoscopic and robotic experience (n = 9) and laparoscopic novices (LN) (n = 20) without any robotic experience performed sequentially 10 trials of a suturing task using either robotic or standard laparoscopic instrumentation fitted to the ProMIS surgical simulator. Objective performance metrics provided by ProMIS (total task time, instrument pathlength, and smoothness) and an assessment of learning curves were analyzed. RESULTS Compared with LNs, the LEs demonstrated significantly better performance on all assessment measures. Within the LE group, there was no difference in smoothness (328 +/- 159 vs 355 +/- 174; P = .09) between robot-assisted and standard laparoscopic tasks. An improvement was noted in total task time (113 +/- 41 vs 132 +/- 55 sec; P < .05) and instrument pathlengths (371 +/- 163 vs 645 +/- 269 cm; P < .05) when using the robot. This advantage in terms of total task time, however, was lost among the LEs by the last 3 trials (114 +/- 40 vs 118 +/- 49 s; P = .84), while instrument pathlength remained better consistently throughout all the trials. For the LNs, performance was significantly better in the robotic trials on all 3 measures throughout all the trials. CONCLUSION The ProMIS surgical simulator was able to distinguish between skill levels (expert versus novice) on robotic suturing tasks, suggesting that the ProMIS is a valid tool for measuring skill in robot-assisted surgery. For all the ProMIS metrics, novices demonstrated consistently better performance on a suturing task using robotics as compared to a standard laparoscopic setup. This effect was less evident for experts who demonstrated improvements only in their economy of movement (pathlength), but not in the speed or smoothness of performance. Robotics eliminated the early learning curve for novices, which was present when they used standard laparoscopic tools. Overall, this study suggests that, when performing complex tasks such as knot tying, surgical robotics is most useful for inexperienced laparoscopists who experience an early and persistent enabling effect. For experts, robotics is most useful for improving economy of motion, which may have implications for the highly complex procedures in limited workspaces (eg, prostatectomy).

AKI in Hospitalized Children: Comparing the pRIFLE, AKIN, and KDIGO Definitions

BACKGROUND AND OBJECTIVES Although several standardized definitions for AKI have been developed, no consensus exists regarding which to use in children. This study applied the Pediatric RIFLE (pRIFLE), AKI Network (AKIN), and Kidney Disease Improving Global Outcomes (KDIGO) criteria to an anonymized cohort of hospitalizations extracted from the electronic medical record to compare AKI incidence and outcomes in intensive care unit (ICU) and non-ICU pediatric populations. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Observational, electronic medical record-enabled study of 14,795 hospitalizations at the Lucile Packard Childrens Hospital between 2006 and 2010. AKI and AKI severity stage were defined by the pRIFLE, AKIN, and KDIGO definitions according to creatinine change criteria; urine output criteria were not used. The incidences of AKI and each AKI stage were calculated for each classification system. All-cause, in-hospital mortality and total hospital length of stay (LOS) were compared at each subsequent AKI stage by Fisher exact and Kolmogorov-Smirnov tests, respectively. RESULTS AKI incidences across the cohort according to pRIFLE, AKIN, and KDIGO were 51.1%, 37.3%, and 40.3%. Mortality was higher among patients with AKI across all definitions (pRIFLE, 2.3%; AKIN, 2.7%; KDIGO, 2.5%; P<0.001 versus no AKI [0.8%-1.0%]). Within the ICU, pRIFLE, AKIN, and KDIGO demonstrated progressively higher mortality at each AKI severity stage; AKI was not associated with mortality outside the ICU by any definition. Both in and outside the ICU, AKI was associated with significantly higher LOS at each AKI severity stage across all three definitions (P<0.001). Definitions resulted in differences in diagnosis and staging of AKI; staging agreement ranged from 76.7% to 92.5%. CONCLUSIONS Application of the three definitions led to differences in AKI incidence and staging. AKI was associated with greater mortality and LOS in the ICU and greater LOS outside the ICU. All three definitions demonstrated excellent interstage discrimination. While each definition offers advantages, these results underscore the need to adopt a single, universal AKI definition.

Providing metrics and performance feedback in a surgical simulator.

One of the most important advantages of computer simulators for surgical training is the opportunity they afford for independent learning. However, if the simulator does not provide useful instructional feedback to the user, this advantage is significantly blunted by the need for an instructor to supervise and tutor the trainee while using the simulator. Thus, the incorporation of relevant, intuitive metrics is essential to the development of efficient simulators. Equally as important is the presentation of such metrics to the user in such a way so as to provide constructive feedback that facilitates independent learning and improvement. This paper presents a number of novel metrics for the automated evaluation of surgical technique. The general approach was to take criteria that are intuitive to surgeons and develop ways to quantify them in a simulator. Although many of the concepts behind these metrics have wide application throughout surgery, they have been implemented specifically in the context of a simulation of mastoidectomy. First, the visuohaptic simulator itself is described, followed by the details of a wide variety of metrics designed to assess the users performance. We present mechanisms for presenting visualizations and other feedback based on these metrics during a virtual procedure. We further describe a novel performance evaluation console that displays metric-based information during an automated debriefing session. Finally, the results of several user studies are reported, providing some preliminary validation of the simulator, the metrics, and the feedback mechanisms. Several machine learning algorithms, including Hidden Markov Models and a Naïve Bayes Classifier, are applied to our simulator data to automatically differentiate users’ expertise levels.

The prevention and treatment of bacterial infections in children with asplenia or hyposplenia: Practice considerations at the Hospital for Sick Children, Toronto

Children born without a spleen or who have impaired splenic function, due to disease or splenectomy, are at significantly increased risk of life‐threatening bacterial sepsis. The mainstays of prevention are education, immunization, and prophylactic antibiotics. The availability of conjugate 7‐valent pneumococcal vaccines for use in children to age 9 years at least, as well as conjugate meningococcal C vaccine in some countries, for use beginning in infancy, appear to represent beneficial additions, but not substitutions, to previous recommendations for the use of polysaccharide 23‐valent pneumococcal and quadrivalent A, C, Y, W‐135 vaccines. Routine immunization against H. influenzae type b should continue with non‐immunized children older than age 5 years receiving two doses 2 months apart, similar to children who have not previously received conjugate pneumococcal vaccine in infancy. Annual influenza immunization, which reduces the risk of secondary bacterial infection, is also recommended for asplenic children and their household contacts. Many experts continue prophylaxis indefinitely although prophylaxis of the penicillin allergic child remains suboptimal.

Multiple Magnet Ingestion as a Source of Severe Gastrointestinal Complications Requiring Surgical Intervention

OBJECTIVE To raise awareness of the dangers associated with magnet ingestion in children. DESIGN Case report and review of the literature. SETTING Tertiary care childrens hospital. Patient Four-year-old boy with minimal physical findings but with a clinical history and imaging suggesting complications from multiple magnet ingestion. Intervention Laparoscopic removal of magnets and repair of magnet-induced enterotomies. Outcome Measure Clinical course. RESULTS Full recovery after surgical intervention. CONCLUSIONS Ingestion of multiple magnets can cause minimal initial physical examination findings but result in significant complications, including bowel perforation, volvulus, ischemia, and death. Early surgical intervention can prevent significant morbidity and mortality. Clinical vigilance should be exercised in these cases and early surgical consultation with an aggressive surgical approach is recommended. Parents should be warned against the dangers of childrens toys that contain these powerful magnets.

The impact of latency on surgical precision and task completion during robotic-assisted remote telepresence surgery

Objective: It has been suggested that robotic-assisted remote telepresence surgery with a signal transmission latency of greater than 300 ms may not be possible. Methods: We evaluated the impact of four different latencies of up to 500 ms on task completion and error rate in five surgeons after completion of three different surgical tasks. Results: The surgeons were able to complete all tasks with a latency of 500 ms. However, higher latency was associated with higher error rates and task completion time (TCT). There were significant variations between surgeons and different tasks. Conclusion: Surgeons are able to complete tasks with a signal transmission latency of up to 500 ms. The clinical impact of slower TCT and increased error rates encountered at higher latency needs to be established.

A Prospective Randomized Trial of Ultrasound- vs Landmark-Guided Central Venous Access in the Pediatric Population

BACKGROUND The purpose of this prospective randomized study was to compare landmark- to ultrasound-guided central venous access when performed by pediatric surgeons. The American College of Surgeons advocates for use of ultrasound in central venous catheter placement; however, this is not universally embraced by pediatric surgeons. Complication risk correlates positively with number of venous cannulation attempts. STUDY DESIGN With IRB approval, a randomized prospective study of children under 18 years of age undergoing tunneled central venous catheter placement was performed. Patient accrual was based on power analysis. Exclusion criteria included known nonpatency of a central vein or coagulopathy. After randomization, the patients were assigned to either ultrasound-guided internal jugular vein access or landmark-guided subclavian/internal jugular vein access. The primary outcomes measure was number of attempts at venous cannulation. Secondary outcomes measures included: access times, number of arterial punctures, and other complications. Continuous variables were compared using 2-tailed Students t-test. Discrete variables were analyzed with chi-square. Significance was defined as p < 0.05. RESULTS There were 150 patients enrolled between April 2008 and September 2011. There was no difference when comparing demographic data. Success at first attempt was achieved in 65% of patients in the ultrasound group vs 45% in the landmark group (p = 0.021). Success within 3 attempts was achieved in 95% of ultrasound group vs 74% of landmark group (p = 0.0001). CONCLUSIONS Ultrasound reduced the number of cannulation attempts necessary for venous access. This indicates a potential to reduce complications when ultrasound is used by pediatric surgeons.

Outcomes of sutureless gastroschisis closure

INTRODUCTION A new technique of gastroschisis closure in which the defect is covered with sterile dressings and allowed to granulate without suture repair was first described in 2004. Little is known about the outcomes of this technique. This study evaluated short-term outcomes from the largest series of sutureless gastroschisis closures. METHODS AND PATIENTS A retrospective case control study of 26 patients undergoing sutureless closure between 2006 and 2008 was compared to a historical control group of 20 patients with suture closure of the abdominal fascia between 2004 and 2006. Four major outcomes were assessed: (1) time spent on ventilator, (2) time to initiating enteral feeds, (3) time to discharge from the neonatal intensive care unit, and (4) rate of complications. RESULTS In multivariate analysis, sutureless closure of gastroschisis defects independently reduced the time to extubation as compared to traditional closure (5.0 vs 12.1 days, P = .025). There was no difference in time to full enteral feeds (16.8 vs 21.4 days, P = .15) or time to discharge (34.8 vs 49.7 days, P = .22) with sutureless closure. The need for silo reduction independently increased the time to extubation (odds ratio, 4.2; P = .002) and time to enteral feeds (odds ratio, 5.2; P < .001). Small umbilical hernias were seen in all patients. CONCLUSION Sutureless closure of uncomplicated gastroschisis is a safe technique that reduces length of intubation and does not significantly alter the time required to reach full enteral feeds or hospital discharge.

Short- and long-term outcomes of necrotizing enterocolitis in infants with congenital heart disease.

OBJECTIVE. Congenital heart disease is a significant risk factor for necrotizing enterocolitis in the term infant. We compared the short- and long-term necrotizing enterocolitis–specific outcomes of infants with congenital heart disease with those of neonates without congenital heart disease. PATIENTS AND METHODS. A retrospective study of 202 patients with necrotizing enterocolitis treated at our center from May 1999 to August 2007 was conducted. Infants with necrotizing enterocolitis were grouped according to the presence (n = 76) or absence (n = 126) of congenital heart disease. Demographic and necrotizing enterocolitis–specific outcomes were recorded. The groups were compared by nonparametric and χ2 analyses. Univariate and multivariate odds ratios were determined for each outcome. RESULTS. The average birth weight and gestational age of the 2 groups were not significantly different. The initial necrotizing enterocolitis severity, as determined by Bell stage, was less for necrotizing enterocolitis subjects with congenital heart disease compared with those without congenital heart disease. When controlling for birth weight and gestational age, the congenital heart disease group had decreased risk of perforation, need for a bowel operation, strictures, need for a stoma, sepsis, and short bowel syndrome compared with the non–congenital heart disease group. Although not statistically significant, subjects with congenital heart disease had a trend toward decreased risk of death from necrotizing enterocolitis, recurrent necrotizing enterocolitis, and need for peritoneal drainage. CONCLUSIONS. Infants with congenital heart disease and necrotizing enterocolitis have decreased risk of major short- and long-term negative outcomes associated with necrotizing enterocolitis compared with neonates without congenital heart disease. Differences in initial severity, range of age at diagnosis, and prognoses between subjects with necrotizing enterocolitis with and without cardiac disease suggest that necrotizing enterocolitis in the cardiac patient is a distinct disease process and should be labeled cardiogenic necrotizing enterocolitis.