Gregory J. Mancini

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.

Nationwide Impact of Laparoscopic Lysis of Adhesions in the Management of Intestinal Obstruction in the US

BACKGROUND Treatment of adhesion-related complications is cost intensive and presents a considerable burden to the health care system. The objective of this study was to compare open (OLA) and laparoscopic lysis of adhesions (LLA) in the treatment of intestinal obstruction, based on a nationwide representative sample. STUDY DESIGN Patients with intestinal obstruction undergoing OLA, LLA, and conversion were identified from the 2002 National Inpatient Sample. After propensity methods were used to adjust for covariates including patient demographics, hospital characteristics, and comorbidities, the impact of OLA and LLA was analyzed concerning in-hospital mortality, postoperative complications, length of stay (LOS), and in-hospital costs. RESULTS Of 6,165 patients, 88.6% underwent OLA and 11.4% had LLA. Conversion was required in 17.2% of LLA patients. Unadjusted mortality was equal between LLA and conversion (1.7%) and half the rate compared with OLA (3.4%) (p = 0.014). After adjusting with propensity methods, the odds of complications in the LLA group (intention to treat) were 25% less than in the OLA (p = 0.008). The LLA group had a 27% shorter LOS (p = 0.0001) and was 9% less expensive than the OLA group (p = 0.0003). There was no statistical significant difference for LOS, complications, and costs between the conversion and OLA groups. CONCLUSIONS Results from this study suggest that when LLA is applied to selected patients with intestinal obstruction, there are reductions in postoperative complications, LOS, and costs. Prospective studies are needed to confirm these data and better identify the subgroup of patients who have improved outcomes with LLA.

Design of a unified active locomotion mechanism for a capsule-shaped laparoscopic camera system

This paper proposes a unified active locomotion mechanism for a capsule-shaped laparoscopic surgical camera system. The proposed design integrates the cameras fixation and manipulation together by adjusting a 3D rotational magnetic field from a stator outside a patients body. The stator generates both torque to rotate the inside rotor dome in all three dimensions, and force to serve as an anchoring system that keeps the camera steady during a surgical procedure. This design eliminates the need for an articulated design and therefore the integrated motors to significantly reduce the size of the camera. A set of stator and rotor designs are developed and evaluated by simulations and experiments.

Design and analysis of a magnetic actuated capsule camera robot for single incision laparoscopic surgery

This paper presents the design of a novel insertable robotic capsule camera system for single incision laparoscopic surgery. This design features a unified mechanism for anchoring, navigating, and rotating an insertable camera by externally generated rotational magnetic field. The design is inspired by the spherical motor concept where the external stator generates anchoring and rotational magnetic field to control the motion of the insertable robotic capsule camera. The insertable camera body, which has no active locomotion mechanism onboard, is capsulated in a one-piece housing with two ringshaped tail-end magnets and one cylindrical central magnet embedded on-board as a rotor. The stator positioned outside an abdominal cavity consists of both permanent magnets and electromagnetic coils for generating reliable rotational magnetic field. The initial prototype results in a compact insertable camera robot with a 12.7mm diameter and a 68mm length. The design concepts are analyzed theoretically and verified experimentally. The experiments validate that the proposed capsule robot design provides reliable camera fixation and locomotion capabilities under various testing conditions.

Design of a unified active locomotion mechanism for a wireless laparoscopic camera system

This paper proposes an active locomotion mechanism for a wireless laparoscopic surgical camera. The mechanism consists of a stator with 17 iron-core coils and a rotor with 3 cylindrical permanent magnets inside the camera. Our motor-free design unifies the cameras fixation and manipulation by adjusting input currents in the stator which generates 3D rotational magnetic fields, and decouples the cameras locomotion into pan motion and tilt motion. In the simulation studies, our proposed design can conservatively achieve 360° pan motion with a 22.5° resolution, and 127° ~ 164° maximum tilting range for tilt motion which depends on tilt motion working modes and the distance between the rotor and the stator.

Control of a Magnetic Actuated Robotic Surgical camera system for single incision laparoscopic surgery

This paper demonstrates a Magnetic Actuated Robotic Surgical (MARS) camera system with two-degree-of-freedom (2-DOF) orientation control for single incision laparoscopic surgery. The MARS camera design that consists of a stator and a rotor features a unified mechanism for anchoring, navigating, and rotating the insertable camera by externally generated rotational magnetic field from the stator. The insertable camera that has no on-board motors is capsulated in a one-piece housing with two ring-shaped tail-end magnets and one cylindrical central magnet as the rotor. The stator positioned outside an abdominal cavity consists of both permanent magnets and electromagnetic coils to generate rotational magnetic field. A closed-loop control system was developed to enable automatic fine orientation control of the MARS camera. The experimental investigations indicated that our MARS camera can achieve 0.67° and 0.49° control accuracies for tilt and pan motions respectively.

Design of a Magnetic Actuated Fully Insertable Robotic Camera System for Single-Incision Laparoscopic Surgery

This paper presents the design of a novel insertable robotic capsule camera system for single-incision laparoscopic surgery. This design features a unified mechanism for anchoring, navigating, and rotating a fully insertable camera by externally generated rotational magnetic field. The design is inspired by the spherical motor concept where the external stator generates anchoring and rotational magnetic field to control the motion of the insertable robotic capsule camera. The insertable camera body, which has no active locomotion mechanism onboard, is capsulated in a one-piece housing with two ring-shaped tail-end magnets and one cylindrical central magnet embedded onboard as a rotor. The stator positioned outside an abdominal cavity consists of both permanent magnets and electromagnetic coils for generating reliable rotational magnetic field. The initial prototype results in a compact insertable camera robot with a

Multimodal cytoreduction for carcinoid liver metastases: analysis of a case series with highly advanced disease

\text{12.7}\;\text{mm}

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

diameter and a

Fine Orientation Control of An Insertable Robotic Camera System for Single Incision Laparoscopic Surgery

\text{68 mm}