Lag-time effects of vaccination on SARS-CoV-2 dynamics in German hospitals and intensive-care units.

Background: The Efficacy and effectiveness of vaccination against SARS-CoV-2 have clearly been shown by randomized trials and observational studies. Despite these successes on the individual level, vaccination of the population is essential to relieving hospitals and intensive care units. In this context, understanding the effects of vaccination and its lag-time on the population-level dynamics becomes necessary to adapt the vaccination campaigns and prepare for future pandemics. Methods: This work applied a quasi-Poisson regression with a distributed lag linear model on German data from a scientific data platform to quantify the effects of vaccination and its lag times on the number of hospital and intensive care patients, adjusting for the influences of non-pharmaceutical interventions and their time trends. We separately evaluated the effects of the first, second and third doses administered in Germany. Results: The results revealed a decrease in the number of hospital and intensive care patients for high vaccine coverage. The vaccination provides a significant protective effect when at least approximately 40% of people are vaccinated, whatever the dose considered. We also found a time-delayed effect of the vaccination. Indeed, the effect on the number of hospital patients is immediate for the first and second doses while for the third dose about 15 days are necessary to have a strong protective effect. Concerning the effect on the number of intensive care patients, a significant protective response was obtained after a lag time of about 15-20 days for the three doses. However, complex time trends, e.g. due to new variants, which are independent of vaccination make the detection of these findings challenging. Conclusion: Our results provide additional information about the protective effects of vaccines against SARS-CoV-2; they are in line with previous findings and complement the individual-level evidence of clinical trials. Findings from this work could help public health authorities efficiently direct their actions against SARS-CoV-2 and be well-prepared for future pandemics.

Intensity and lag-time of non-pharmaceutical interventions on COVID-19 dynamics in German hospitals.

Introduction: Evaluating the potential effects of non-pharmaceutical interventions on COVID-19 dynamics is challenging and controversially discussed in the literature. The reasons are manifold, and some of them are as follows. First, interventions are strongly correlated, making a specific contribution difficult to disentangle; second, time trends (including SARS-CoV-2 variants, vaccination coverage and seasonality) influence the potential effects; third, interventions influence the different populations and dynamics with a time delay. Methods: In this article, we apply a distributed lag linear model on COVID-19 data from Germany from January 2020 to June 2022 to study intensity and lag time effects on the number of hospital patients and the number of prevalent intensive care patients diagnosed with polymerase chain reaction tests. We further discuss how the findings depend on the complexity of accounting for the seasonal trends. Results and discussion: Our findings show that the first reducing effect of non-pharmaceutical interventions on the number of prevalent intensive care patients before vaccination can be expected not before a time lag of 5 days; the main effect is after a time lag of 10-15 days. In general, we denote that the number of hospital and prevalent intensive care patients decrease with an increase in the overall non-pharmaceutical interventions intensity with a time lag of 9 and 10 days. Finally, we emphasize a clear interpretation of the findings noting that a causal conclusion is challenging due to the lack of a suitable experimental study design.

Significant pressure differences between solid-state and water-perfused systems in lower esophageal sphincter measurement.

OBJECTIVE: High-resolution manometry of the esophagus has gained worldwide acceptance, using different solid-state catheters. Thus, normal values for lower esophageal sphincter (LES) resting pressure in suspected gastroesophageal reflux disease patients have been established using water-perfused manometry. These standard values are commonly applied using also solid-state techniques, although they have never been compared before. The aim of the study was to compare LES measurements obtained with water-perfused manometry with a solid-state technique. METHODS: Thirty healthy subjects were studied twice on the same day: Technique 1: Station pull through using a water-perfused catheter with ports arranged at 0°, 90°, 180° and 270° which were averaged to give a mean LES pressure. Technique 2: Solid-state circumferential probe with a single station pull through. Data were collected using the same computer system and program. The LES pressures were randomly and blindly analyzed. RESULTS: Twenty-seven subjects out of 30 were analyzed. Using the solid-state system, the mean LES pressure was higher (15.0 vs. 23.3 mmHg, p = 0.003) and 19 of 27 (70%) individual measurements were higher. Two subjects had a hypertensive LES by solid state (58.6 resp. 47.5 mmHg), while their pressures were normal with water-perfused manometry (21.0 resp. 23.4 mmHg). The distal esophageal pressures (mean of pressure at 3 and 8 cm above LES) were the same with the two techniques. CONCLUSION: In normal control subjects, LES measurement using circumferential solid-state transducers yields higher pressures than standard water-perfused manometry. Which system yields the "true" resting pressure of the physiologic LES remains to be determined.

Perforated Meckel's diverticulum presenting as a gastrointestinal stromal tumor: a case report.

Tumors and perforation of Meckel's diverticulum are rare manifestations. A gastrointestinal stromal tumor in a Meckel's diverticulum causing perforation and subsequent peritonitis in a 75-year-old man is presented. The literature on tumors in Meckel's diverticulum is extensively reviewed and discussed.

Long-term follow-up after robotic cholecystectomy.

Most surgeons gain their first clinical experience with surgical robots when performing cholecystectomies. Although this procedure is rather easily applicable for the da Vinci surgical system, the long-term outcome after this operation has not yet been clarified. This study follows up our institutional first series of robotic cholecystectomies (June to November 2001). Patients were assessed on the basis of standardized management including a quality-of-life questionnaire, clinical examination, blood tests, and abdominal sonogram. The follow-up rate for 23 patients after robotic cholecystectomy was 100 per cent and the median follow-up time 33 (30-35) months. There was one (4%) recurrence of gallstone disease in a patient who suffered from solitary choledocholithiasis 29 months after robotic cholecystectomy. Abdominal sonogram, clinical examinations, and blood tests revealed no post-cholecystectomy-specific pathological findings. The main long-term symptoms were bloating (57%), heartburn (43%) and nausea (30%). Of the patients, 96 per cent (22 patients) felt that the operation had cured or significantly improved their specific preoperative symptoms. Long-term results after robotic laparoscopic cholecystectomy are excellent and comparable to those for the conventional laparoscopic procedure. The advanced vision control and instrument maneuverability of robotic surgery might open minimally invasive surgery also for complicated gallstone disease and bile duct surgery.

Nissen or partial posterior fundoplication: which antireflux procedure has a lower rate of side effects?

INTRODUCTION: In patients with gastroesophageal reflux disease (GERD) it is still controversial as to which type of antireflux procedure-the Nissen or the partial posterior fundoplication-offers the lower rate of side effects in the long term. PATIENTS AND METHODS: In this follow-up study the Nissen fundoplication was performed only in GERD patients with normal oesophageal peristalsis. The partial posterior fundoplication was preserved for patients with weak peristalsis. Only patients with effective postoperative control of GERD were included in the study. The study groups consisted of 77 patients who underwent the Nissen fundoplication and 132 patients who underwent partial posterior fundoplication. Clinical assessment of side effects was performed after a median of 52 months following surgery. Manometric assessment of the lower esophageal sphincter (LES) and of esophageal peristalsis was achieved 6 months after surgery. RESULTS: Side effects such as dysphagia, bloating, inability to belch and vomit, epigastric pain and early satiety were significantly more common after the Nissen fundoplication than after partial posterior fundoplication. Improvement of the antireflux barrier was equal in both groups; however, LES relaxation was incomplete following the Nissen fundoplication but normal after partial posterior fundoplication. Partial posterior fundoplication resulted in improved oesophageal peristalsis, whereas the Nissen fundoplication caused slight impairment of peristalsis. CONCLUSIONS: Partial posterior fundoplication is a more physiological antireflux procedure than the Nissen fundoplication, and, therefore, this operation has now become our preferred technique for all GERD patients.

Comparison of methods for determining cricopharyngeal intrabolus pressure in normal patients as possible indicator for cricopharyngeal myotomy.

OBJECTIVE: We sought to compare methods for determining intrabolus cricopharyngeal pressure as a possible indicator for cricopharyngeal myotomy. STUDY DESIGN: We determined multiple intrabolus pressures in the cricopharyngeal region of 20 normal volunteers, of whom 12 were 20 to 35 years old and 8 were older than 75 years. Data were collected using a commercially available manofluorography system and a 6-sensor unidirectional solid-state 2- x 4-mm catheter. Each subject underwent 5 5-mL and 5 10-mL liquid barium swallows. Data were analyzed, and young subjects were compared with old subjects. RESULTS: The mean mid-bolus pressures in young subjects were 5.2 +/- 4.9 mm Hg and 7.2 +/- 6.5 mm Hg for the 5-mL and 10-mL swallows, respectively, and in older subjects, 10.8 +/- 8.8 mm Hg and 12.3 +/- 7.4 mm Hg. The mean gradient pressures across the 3-cm cricopharyngeal region in young subjects were 2.02 +/- 5.0 mm Hg, and -0.91 +/- 4.8 mm Hg for the 5-mL and 10-mL swallows, respectively, and for older subjects, 4.38 +/- 3.1 mm Hg and 2.82 +/- 3.4 mm Hg. CONCLUSIONS: Cricopharyngeal intrabolus pressures were lower in young than in older subjects. The mid-bolus pressure and the gradient pressure across the cricopharyngeal region appeared to be the most consistent methods for evaluating intrabolus pressures. SIGNIFICANCE: Intrabolus pressure anomalies in the cricopharyngeal region have been proposed as an indicator for selecting patients who would benefit from cricopharyngeal myotomy. The methods of determining intrabolus pressures vary, with resulting variations in recommendations.