Low-volume Setting Research Articles

Is Laparoscopic Appendectomy Safe When Performed in a Low Volume Setting?

Background: Similar to global trends, laparoscopic appendectomy has gained favor across the Caribbean but there is a paucity of published data evaluating its outcomes in the region. This study seeks to document the outcomes of laparoscopic appendectomies performed by community surgeons in a low volume setting in the Caribbean. Methods: Data were recorded prospectively from all consecutive laparoscopic appendectomies performed from June 1, 2006 to May 30, 2011. Complicated appendicitis was considered present when the appendix was gangrenous, perforated, phlegmonous and/or associated with a peri-appendiceal abscess. Data were analyzed using SPSS version 19. Results: Appendectomies were performed by one of three surgeons in 167 patients (mean case volume 11 cases per surgeon per year) at mean age of 31.8 ±9.67 years and mean BMI of 29.3 ± 2.59 Kg/m2. There was a 14% negative appendectomy rate. Of 143 patients with confirmed appendicitis, 73% were uncomplicated cases and 24% were complicated appendicitis. The mean operating time was 50.1 ±18.4 minutes for uncomplicated cases and 98.8 ±21.6 minutes for complicated appendicitis. The overall morbidity rate was 4.2% (1.8% morbidity in uncomplicated cases and 14.7% for complicated appendicitis. Post-operatively, 69% patients required no supplemental parenteral opioids. After discharge, 7% patients required no oral analgesia and 90% stopped their analgesics within 48 hours. Conclusions: Laparoscopic appendectomy is a safe operation when performed by community surgeons at low volumes and should be considered as a part of the surgical armamentarium.

Safety of laparoscopic colorectal surgery in a low-volume setting: review of early and late outcome.

Background. There is increasing evidence suggesting that the laparoscopic technique is the treatment of choice for large bowel resection, including for malignancy. The purpose of the study was to assess whether general surgeons, with particular skills in advanced laparoscopy, can adequately provide safe laparoscopic colorectal resections in a low-volume setting. Methods. A retrospective review of prospectively collected case series of all laparoscopic colorectal resections performed under the care of a single general surgeon is presented. The primary endpoint was postoperative clinical outcome in terms of morbidity and mortality. Secondary endpoints were adequacy of surgical margins and number of lymph nodes harvested for colorectal cancer cases. Results. Seventy-three patients underwent 75 laparoscopic resections between March, 2003, and May, 2011. There was no elective mortality and the overall 30-day postoperative morbidity was 9.3%. Conversion and anastomotic leakage rates were both 1.3%, respectively. None of the malignant cases had positive margins and the median number of lymph nodes retrieved was 17. Conclusions. Our results support the view that general surgeons with advanced skills in minimally invasive surgery may safely perform laparoscopic colorectal resection in a low-volume setting in carefully selected patient cases.

Adequacy of lymph node examination in colorectal surgery: contribution of the hospital versus the surgeon.

Examination of at least 12 lymph nodes (LNs) in the staging of colon cancer (CC) was recommended by the National Comprehensive Cancer Network in 2000; however, rates of an adequate examination remain low. This study compares the impact of the hospital contextual variance against that of the operating surgeon on delivery of an adequate LN examination. Retrospective analysis of California Cancer Registry data for all CC operations (2001-2006). Hierarchical models predicted the adequacy of LN examination as a function of patient, surgeon, and hospital characteristics. Models were created using penalized quasi-likelihood approximation with second order Taylor linearization as implemented in MLwiN 2.15. A total of 25,606 resections involving 3376 surgeons operating in 346 hospitals were analyzed. Half of cases had an adequate examination. Hierarchical models showed the median odds of an adequate examination associated with the hospital context [(MORhosp 2.05; 95% confidence interval, 1.9-2.2) was much higher than that associated with the surgeon (MORsurg 1.34; 95% confidence interval, 1.2-1.4)]. Hospital characteristics teaching and high volume predicted higher odds of an adequate examination. There was no association with hospital revenue. Approximately half of patients undergoing surgery for CC received an adequate LN examination. Hospital contextual factors had a stronger association with receipt of an adequate examination than surgeon factors. Our results suggest that quality improvement initiatives and incentives should be targeted at the hospital level to achieve the highest impact. Furthermore, we have identified nonteaching and low volume settings as rational targets for these efforts.

The Technique and Cost of Radiosurgery for the Treatment of 1-3 Brain Metastases

Radiosurgery can be delivered through a variety of modalities including robotic and fixed gantry Linac-based systems. They appear equally effective and safe. Thus, community need and costs remain the main determinants for choosing a given modality. We performed an economic evaluation to identify settings in which one modality could be preferred over the other. Using local estimates of resource volumes and unit prices, we computed the incremental cost/patient of robotic radiosurgery compared to fixed-gantry radiosurgery from a payer's perspective. By varying parameters of resource volumes, we performed a probabilistic analysis stratified by number of brain lesions. in addition, we performed sensitivity analyses to examine the effect of patient volume on cost/patient. The cost of robotic radiosurgery was $4,783/patient, and cost of fixed-gantry radiosurgery was $5,166/patient. The mean incremental cost was $-383 (95% interval: $-670, $110) for all lesions, $78 ($23, $123) for solitary lesions, and $-610 ($-679, $-534) for multiple lesions. The cost/patient of robotic radiosurgery varied from $5,656 (low volume setting) to $4,492 (high volume setting). in settings of moderate to high volume (6-10 hours of daily operation), and in multiple lesions, robotic radiosurgery is more cost effective than fixed-gantry radiosurgery.

Impact of noradrenaline infusion set on mean arterial pressure: A retrospective clinical study

ObjectivesNoradrenaline (NA) can be infused through various systems including single or double syringe pumps. The aim of this study was to define the best and most efficient infusion system in an emergency context. Study designThis was a retrospective clinical study based on the analysis of patients’ hemodynamic data. Patients and methodThree infusion lines used presently in our postoperative ICU were compared through a retrospective clinical study: an NA syringe pump at 2mL/h and a saline carrier solution syringe pump at 8mL/h (infusion system 1- IS1) or 5mL/h (IS2), both connected to a very low dead-space volume set (V=0.046mL); IS3 with the same NA syringe at 2mL/h directly connected to the central venous catheter. Mean arterial pressure (MAP) was obtained from retrospective data analysis of ICU patients with postoperative septic shock criteria. Infusion systems were compared according to the time required to reach an MAP greater than 65mmHg after the onset of infusion. ResultsData from 37 patients was analysed. The MAP objective was attained in 14:00minutes (9:20 – 26:10, n=15) with IS1, in 19:10minutes (12:20 – 27:20, n=13) with IS2 and in 34:10minutes (23:10 – 62:30, n=9) with IS3 (P=0.00032). ConclusionThe use of a double syringe pump system associated with a very low dead-space volume infusion set appears to be the most appropriate system for NA infusion.

Prophylactic protective ventilation: lower tidal volumes for all critically ill patients?

High tidal volumes have historically been recommended for mechanically ventilated patients during general anesthesia. High tidal volumes have been shown to increase morbidity and mortality in patients suffering from acute respiratory distress syndrome (ARDS). Barriers exist in implementing a tidal volume reduction strategy related to the inherent difficulty in changing one's practice patterns, to the current need to individualize low tidal volume settings only for a specific subgroup of mechanically ventilated patients (i.e., ARDS patients), the difficulty in determining the predicated body weight (requiring the patient's height and a complex formula). Consequently, a protective ventilation strategy is often under-utilized as a therapeutic option, even in ARDS. Recent data supports the generalization of this strategy prophylactically to almost all mechanically ventilated patients beginning immediately following intubation. Using tools to rapidly and reliably determine the predicted body weight (PBW), as well as the use of automated modes of ventilation are some of the potential solutions to facilitate the practice of protective ventilation and to finally ventilate our patients' lungs in a more gentle fashion to help prevent ARDS.

Laxative Abuse, Eating Disorders, and Kidney Stones: A Case Report and Review of the Literature

Kidney stones are listed among the complications of eating disorders; however, very few cases have been reported. We present an additional case of nephrolithiasis associated with laxative abuse, including detailed results of the patient's urine metabolic profiles, in a patient with idiopathic hypercalciuria. We review the literature and provide an explanation for the paucity of cases of nephrolithiasis associated with these disorders. Despite low urine volumes resulting from extracellular fluid volume depletion and hypocitraturia resulting from hypokalemia, both of which would tend to favor the formation of kidney stones, most patients with eating disorders are likely to be protected from stone formation by the hypocalciuric effect of extracellular fluid volume depletion and increased proximal tubular sodium reabsorption. However, patients with underlying idiopathic hypercalciuria who develop eating disorders may be at increased risk of stone formation in the setting of low urine volume and therefore high supersaturation of calcium oxalate and phosphate.

Visualization versus Neuromonitoring of Recurrent Laryngeal Nerves during Thyroidectomy: What About the Costs?

The objective of the present study was to evaluate costs for thyroidectomy performed with the aid of intraoperative neural monitoring (IONM), which has gained widespread acceptance during thyroid surgery as an adjunct to the gold standard of visual nerve identification. Through a micro-costing approach, the thyroidectomy patient-care process (with and without IONM) was analyzed by considering direct costs (staff time, consumables, equipment, drugs, operating room, and general expenses). Unit costs were collected from hospital accounting and standard tariff lists. To assess the impact of the IONM technology on hospital management, three macro-scenarios were considered: (1) traditional thyroidectomy; (2) thyroidectomy with IONM in a high-volume setting (5 procedures per week); and (3) thyroidectomy with IONM in a low-volume setting (1 procedure per week). Energy-based devices (EBD) for hemostasis and dissection in thyroidectomy were also evaluated, as well as the reimbursement made by the Italian Healthcare System on the basis of diagnosis related groups (DRGs), about €2,600. Comparison between costs and the DRG fee shows an underfunding of total hospitalization costs for all thyroidectomies, regardless of IONM use (scenario 1: €3,471). The main cost drivers are consumables and technologies (25%), operating room (16%), and staff (14%). Hospitalization costs for a thyroidectomy with IONM range from €3,713 to €3,770 (scenarios 2 and 3), 5–7% higher than those for traditional thyroidectomy. Major economic differences emerge when an EBD is used (€3,969). The regional DRG tariff for thyroid surgery is barely sufficient to cover conventional surgery costs. Intraoperative neural monitoring accounts for 5–7% of the hospitalization costs for a thyroidectomy.

The Impact on Drug Mass Flow Rate of Interrupting and Resuming Carrier Fluid Flow

Stopping and resuming carrier fluid flow can lead to potentially dangerous transient disturbances in drug mass flow rate. We compared the impact of 2 infusion sets, one with very low dead-space volume and the other with greater dead-space volume, on the amount of drug delivered during stop-and-go carrier fluid flows. Two infusion sets, both with antireflux, connected to an angiocatheter and with dead-space volumes of 6.185 mL and 0.071 mL, respectively, were assessed. Two protocols were studied: carrier fluid flow of 90 mL/h associated with noradrenaline infused at 7 mL/h and carrier fluid flow of 350 mL/h with a noradrenaline infusion flow of 65 mL/h. During both protocols, the carrier fluid was stopped and resumed at the same rate 30 minutes later. Effluent noradrenaline concentration was measured using UV spectrophotometry. Flow change efficiency was calculated from the ratio of the area under the experimental mass flow rate curve to the area under the theoretical instantaneous mass flow rate curve. For both flow rate conditions, flow change efficiency was significantly different for the 2 infusion sets during the 10-minute period after stopping carrier fluid flow and the 10-minute period after restarting it. The major phenomena were sudden decreases in drug delivery after stopping carrier flow and sudden, temporary increases when it was resumed. The very low dead-space volume infusion set resulted in significant reduction in changes in drug delivery compared with the standard set, even at high flow rates. The use of a very low dead-space volume set attenuates disturbances in drug delivery caused by interrupting and resuming carrier fluid flow.

Commentary on Development of a Support Tool for Complex Decision-Making

Hearns, Klein and colleagues set out to develop a maternity care decision-making tool for the British Columbia Northern Health Authority to assist with assessing community needs and values. They are to be commended for thinking outside the traditional decision-making approach which focuses, as they say, on “administration, fiscal and safety issues. Solutions often follow previously made decisions … [because] this approach is less time-consuming, simpler and safer.” They go on to point out the problems with this approach, such as minimal engagement of community members or representation of their interests, potentially resulting in disempowerment and bitterness. They claim that their process rectifies this lack of engagement:

IPods listening levels on London Underground

In the last 5 years the prevalence of the iPod/MP3 players has grown exponentially. The use of such in‐earphones under urban conditions has been reported widely in the press at the anecdotal level. This study compared listening levels under quiet conditions and that representative of a London Underground train journey. Calibrated recordings of underground trains running in tunnels were played through loudspeakers in an anechoic chamber, whilst pop music or speech podcasts were played through the iBuds. Thirty‐three participates listened to the iPod whilst a Binaural Head and Torso measured the noise levels through the in‐earphones. The participants had time to adjust the volume setting on each occasion. A small audiometric study was undertaken for those participates with particularly high and low volume settings a week after the tests were completed. Results show very high volume settings were used when speech was played with the train noise.

Outcome issues of mechanical ventilator settings in acute respiratory distress syndrome patients from Québec ICUs after the 2000 Acute Respiratory Distress Syndrome Network trial

Objective. To undertake a retrospective assessment of a knowledge translation of how a low tidal volume setting has affected the overall outcome of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) patients in Quebec ICUs. Material and methods. This was a study of case files from five Quebec ICUs, separated into two groups: those from before and after November 2000 (i.e. 6 months after the publication of the first ARDS Network trial). The primary outcome was changes in tidal volume. Secondary outcomes comprised mortality, number of days without organ dysfunction/failure, positive end-expiratory pressure (PEEP) level, respiratory rate and partial pressure of CO2 (PaCO2). Results. Of 105 patients, 55 were studied before and 50 after the landmark trial. Compared to the situation before November 2000: (i) tidal volume (normalized to predicted ideal body weight) fell; (ii) PEEP, respiratory rate and PaCO2 rose; and (iii) in-hospital mortality decreased and days without organ failure increased ...

Survival after breast cancer treatment: the impact of provider volume

Research has not paid sufficient attention to the need for adequate case-mix adjustment in studies of the relationship between provider volume and performance. This study attempted to address this limitation by capturing and including 5-year survival outcomes and a wide range of case-mix variables in multivariate analyses of the volume-outcome relationship relating to breast cancer treatments. All patients diagnosed with invasive primary breast cancer during 1996 (n = 809) were included. Patient, disease and treatment data were extracted from medical records; survival data were corroborated using official death registrations. A Cox proportional hazards approach was used to model relationships between patient, disease and service variables and risk of death. There were 262 deaths among 807 patients followed up; overall 5-year survival was 70%. Advancing age, higher levels of co-morbidity, late-stage disease, more positive nodes, and high-grade tumour were independently associated with lower survival (P < 0.05). Patients who received hormonal therapy (HR 0.50, 95% CI 0.28-0.89) and radiotherapy (HR 0.73, 95% CI 0.53-1.03) had a survival advantage. Using a cut-off point of > or =30 cases per annum, survival was lower for patients treated in low volume settings (HR 1.47, 95% CI 1.09-1.96) after adjustment for case mix. There was some evidence to support treatment in high volume settings although patient and disease variables were the major determinants of survival for patients with breast cancer.

Testing Blood Glucose at the Bedside in a Chronic Care Hospital

A prospective study was carried out in a chronic care hospital to determine the clinical indications for testing blood glucose (BG) levels at the bedside and to assess the degree of correlation between the clinical impression of the patients’ BG status and the results of these tests. Most (94%) BG tests performed on inpatients at the bedside were done to monitor routine treatment and did not require the rapid turnaround time afforded by this type of testing. Clinical estimation of BG status was highly inaccurate, which presents the argument for routine monitoring but not for the immediate turnaround provided by this method. The cost of BG testing at the bedside in low-volume settings is high, and the method is periodically unreliable. These disadvantages must be weighed against the undocumented advantages of the method: shorter hospital stays and more rapid stabilization of BG levels.

Pleural Lymphatics as Regulators of Pleural Fluid Dynamics

Pleural fluid is filtered across the parietal mesothelium in the top of the pleural cavity and removed by lymphatic stomatas in the more dependent mediastinal and diaphragmatic regions. The pleural lymphatics act as a feedback system that regulates pleural liquid volume and its protein composition around a low volume set point.