Distinguishing patterns in the dynamics of long-term medication use by Markov analysis: beyond persistence

Background  

In order to accurately distinguish gaps of varying length in drug treatment for chronic conditions from discontinuation without resuming therapy, short-term observation does not suffice. Thus, the use of inhalation corticosteroids (ICS) in the long-term, during a ten-year period is investigated. To describe medication use as a continuum, taking into account the timeliness and consistency of refilling, a Markov model is proposed.     

Long-term impact of pneumoperitoneum used for laparoscopic donor nephrectomy on renal function and histomorphology in donor and recipient rats

OBJECTIVE: To investigate the long-term impact of pneumoperitoneum used for laparoscopic donor nephrectomy on renal function and histomorphology in donor and recipient. SUMMARY BACKGROUND DATA: Laparoscopic donor nephrectomy has the potential to increase the number of living kidney donations by reducing donor morbidity. However, function of laparoscopically procured kidneys might be at risk due to ischemia as a consequence of elevated intra-abdominal pressure during laparoscopy. METHODS: In experiment 1, 30 Brown Norway rats were randomized to three procedures: 2 hours of CO2 insufflation, 2 hours of helium insufflation, and 2 hours of gasless laparoscopy. After this, a unilateral nephrectomy was performed in all animals. Another six rats were used as controls. In experiment 2, 36 donor Brown Norway rats were subjected to a similar insufflation protocol, but after nephrectomy a syngeneic renal transplantation was performed. All rats had a follow-up period of 12 months. Urine and blood samples were collected each month for determination of renal function. After 1 year, donor and recipient kidneys were removed for histomorphologic and immunohistochemical analysis. RESULTS: In donors as well as in recipients, no significant changes in serum creatinine, proteinuria, or glomerular filtration rate were detected between the CO2, the helium, and the gasless control group after 1 year. No histologic abnormalities due to abdominal gas insufflation were found. Immunohistochemical analysis did not show significant differences in the number of infiltrating cells (CD4, CD8, ED1, OX62, and OX6) and adhesion molecule expression (ICAM-1) between the three groups. CONCLUSIONS: Abdominal gas insufflation does not impair renal function in the donor 1 year after LDN. One year after transplantation, no differences in renal function or histomorphology were detected between kidney grafts exposed to either pneumoperitoneum or a gasless procedure.     

Transoral incisionless fundoplication for treatment of gastroesophageal reflux disease in clinical practice

Background

Transoral incisionless fundoplication is a recently introduced endoluminal technique for the treatment of gastroesophageal reflux disease (GERD). The objective of this study was to determine outcomes in chronic GERD patients who were referred for surgical management.

Methods

A cohort of 38 patients underwent transoral incisionless fundoplication (TIF) in a tertiary care setting. Pre- and post-procedure assessment included GERD-related quality of life questionnaires, proton pump inhibitor (PPI) usage, 24-h pH measurements, upper gastrointestinal endoscopy, esophageal manometry, and registration of adverse events. Duration of follow-up was 36?months.

Results

Gastroesophageal valves were constructed of 4?cm (range, 4–6) in length and 220° (range, 180–240) in circumference. One serious adverse event occurred, consisting of intraluminal bleeding at a fastener site. Hiatal hernia was completely reduced in 56?% and esophagitis was cured in 47?% of patients. Postprocedure esophageal acid exposure did not significantly improve (p?>?0.05). At 36 (range, 29–41) months follow-up 14 patients (36?%) had undergone revisional laparoscopic fundoplication. Quality of life scores of the remaining cohort showed significant improvement (p?<?0.0001) and daily use of antisecretory medication was discontinued by 74?%.

Conclusions

Endoluminal fundoplication improved quality of life and reduced the need for PPIs in only a subgroup of patients at 3?years follow-up. The amount of patients requiring additional medication and revisional surgery was high.     

Revisional laparoscopic antireflux surgery after unsuccessful endoscopic fundoplication

Background

Transoral incisionless fundoplication (TIF), a novel endoscopic procedure for treating gastroesophageal reflux disease (GERD), currently is under evaluation. In case of treatment failure, subsequent revisional laparoscopic antireflux surgery (rLARS) may be required. This study aimed to evaluate the feasibility, safety, and outcomes of revisional antireflux surgery after previous endoscopic fundoplication.

Methods

Chronic GERD patients who underwent rLARS after a previous TIF procedure were included in the study. Pre- and postoperative assessment included GERD-related quality-of-life scores, proton pump inhibitor (PPI) usage, 24-h pH-metry, upper gastrointestinal endoscopy, and registration of adverse events.

Results

Revisional laparoscopic Nissen fundoplication was feasible for all 15 patients included in the study without conversions to open surgery. Acid exposure of the distal esophagus improved significantly after rLARS, and esophagitis, PPI usage, and hiatal hernia decreased. Quality of life did not improve significantly after rLARS, and 33 % of the patients experienced dysphagia.

Conclusion

Revisional laparoscopic Nissen fundoplication was feasible and safe after unsuccessful endoscopic fundoplication, resulting in objective reflux control at the cost of a relatively high rate of dysphagia.     

Advanced intraoperative imaging methods for laparoscopic anatomy navigation: an overview

Background

Safety and efficiency are important topics in minimally invasive surgery. Apart from its advantages, laparoscopic surgery has the following drawbacks: two-dimensional imaging, challenging eye–hand coordination, and absence of tactile feedback. Enhanced imaging with earlier and clearer identification of essential tissue types can partly overcome these disadvantages. Research groups worldwide are investigating new technologies for image-guided surgery purposes. This review article gives an overview of current developments in surgical optical imaging for improved anatomic identification and physiologic tissue characterization during laparoscopic gastrointestinal surgery.

Methods

A systematic literature search in the PubMed database was conducted. Eligible studies reported on any kind of novel optical imaging technique applied for anatomic identification or physiologic tissue characterization in laparoscopic gastrointestinal surgery. Gynecologic and urologic procedures also were included whenever vascular, nerve, ureter, or lymph node imaging was concerned.

Results

Various surgical imaging techniques for enhanced intraoperative visualization of essential tissue types (i.e., blood vessel, bile duct, ureter, nerve, lymph node) and for tissue characterization purposes such as assessment of blood perfusion were identified. An overview of preclinical and clinical experiences is given as well as the potential added value for intraoperative anatomic localization and characterization during laparoscopy.

Conclusion

Implementation of new optical imaging methods during laparoscopic gastrointestinal surgery can improve intraoperative anatomy navigation. This may lead to increased patient safety (preventing iatrogenic functional tissue injury) and procedural efficiency (shorter operating time). Near-infrared fluorescence imaging seems to possess the greatest potential for implementation in clinical practice in the near future.