Society for Surgery of the Alimentary Tract State-of-the-Art Session 2022: Frailty in Surgery.

Given the exponentially aging population and rising life expectancy in the United States, surgeons are facing a challenging frail population who may require surgery but may not qualify based on their general fitness. There is an urgent need for greater awareness of the importance of frailty measurement and the implementation of universal assessment of frail patients into clinical practice. Pairing risk stratification with stringent protocols for prehabilitation and minimally invasive surgery and appropriate enhanced recovery protocols could optimize and condition frail patients before, during, and immediately after surgery to mitigate postoperative complications and consequences on patient function and quality of life. In this paper, highlights from the 2022 Society for Surgery of the Alimentary Tract State-of-the-Art Session on frailty in surgery are presented. This work aims to improve the understanding of the impact of frailty on patients and the methods used to augment the outcomes for frail patients during their surgical experience.

Coronary angiography and failure to rescue after postoperative myocardial infarction in patients with coronary stents undergoing noncardiac surgery.

BACKGROUND: We evaluated coronary angiography use among patients with coronary stents suffering postoperative myocardial infarction (MI) and the association with mortality. METHODS: Patients with prior coronary stenting who underwent inpatient noncardiac surgery in Veterans Affairs hospitals between 2000 and 2012 and experienced postoperative MI were identified. Predictors of 30-day post-MI mortality were evaluated. RESULTS: Following 12,096 operations, 353 (2.9%) patients had postoperative MI and 58 (16.4%) died. Post-MI coronary angiography was performed in 103 (29.2%) patients. Coronary angiography was not associated with 30-day mortality (odds ratio [OR]: .70, 95% CI: .35-1.42). Instead, 30-day mortality was predicted by revised cardiac risk index ≥3 (OR 1.91, 95% CI: 1.04-3.50) and prior bare metal stent (OR 2.12, 95% CI: 1.04-4.33). CONCLUSIONS: Less than one-third of patients with coronary stents suffering postoperative MI underwent coronary angiography. Significant predictors of mortality were higher revised cardiac risk index and prior bare metal stent. These findings highlight the importance of comorbidities in predicting mortality following postoperative MI.

A MultiCenter Pilot Randomized Controlled Trial of Remote Ischemic Preconditioning in Major Vascular Surgery.

A pilot randomized controlled trial that evaluated the effect of remote ischemic preconditioning (RIPC) on clinical outcomes following major vascular surgery was performed. Eligible patients were those scheduled to undergo open abdominal aortic aneurysm repair, endovascular aortic aneurysm repair, carotid endarterectomy, and lower limb revascularization procedures. Patients were randomized to RIPC or to control groups. The primary outcome was a composite clinical end point comprising any of cardiovascular death, myocardial infarction, new-onset arrhythmia, cardiac arrest, congestive cardiac failure, cerebrovascular accident, renal failure requiring renal replacement therapy, mesenteric ischemia, and urgent cardiac revascularization. Secondary outcomes were components of the primary outcome and myocardial injury as assessed by serum troponin values. The primary outcome occurred in 19 (19.2%) of 99 controls and 14 (14.1%) of 99 RIPC group patients (P = .446). There were no significant differences in secondary outcomes. Our trial generated data that will guide future trials. Further trials are urgently needed.

The role of venous diameter in predicting arteriovenous fistula maturation: when not to expect an AVF to mature according to pre-operative vein diameter measurements? A best evidence topic.

This best evidence topic was investigated according to a described protocol. We asked the question: what is the minimal vein diameter that can successfully predict maturation of an arteriovenous fistula (AVF) in patients undergoing dialysis. Using the reported search 804 papers were found, of which five represented the best evidence to answer the clinical question. All studies assessed the association between successful AVF maturation and the size of vein used. The strongest evidence came from a nonrandomised controlled follow-up study in which 76% of fistulas created using >2 mm cephalic vein successfully matured compared to 16% when the vein measured ≤2 mm. Another prospective, multicentre study showed 65% successful maturation using veins >4 mm compared to 45% with veins <3 mm. Vein diameter was found to be an independent predictor of maturation in multivariate regression analysis in two retrospective observational studies. Another retrospective observational study found that using venous measurements of ≥2.5 mm following tourniquet application resulted in more fistulas been created that would have otherwise been denied based on venous ultrasound mapping. A large multicentre randomised clinical trial assessing the use of different vein sizes both with and without tourniquet application using proper statistical tools - such as receiver operating characteristic - is required to make a final recommendation. Until then, a vein diameter of <2.5 mm should be considered inadequate for formation of an AVF, particularly if those measurements remain unchanged following the use of tourniquet.

Assessing the quality of online information for patients with carotid disease.

INTRODUCTION: Controversy exists relating to carotid endarterectomy (CEA) versus carotid artery stenting (CAS). We aimed to assess the quality of online patient information relating to both. METHODS: The Google search engine was searched for "carotid endarterectomy" and "carotid stenting". The first 50 webpages returned were assessed. The Gunning Fog Index (GFI) and Flesch Reading Ease Score (FRES) were calculated to assess readability. The LIDA tool (Minervation Ltd., Oxford, U.K.) was used to assess accessibility, usability and reliability. RESULTS: 20% (n = 10) of the webpages returned for CEA were from peer reviewed sources with 34% (n = 17) posted by hospitals or health services. Comparatively, for CAS, 40% (n = 20) were peer reviewed with 16% (n = 8) posted by hospitals or health services. GFI and FRES scores indicated webpages for both CEA and CAS had poor general readability. Webpages for CEA were easier to read than those for CAS (mean FRES difference of 6.7 (95% CI 0.51 to 12.93, p = 0.03). Median LIDA scores demonstrated acceptable reliability, accessibility and usability of information for both CEA and CAS webpages. The more readable webpages were not associated with higher LIDA scores for either CEA or CAS webpages. CONCLUSION: Webpages providing information on carotid disease management must be made more readable. Online information currently available to patients regarding CAS is more difficult to read and comprehend than CEA.

The impact of regional reconfiguration on the management of appendicitis.

BACKGROUND: Reconfiguration of surgical services in the Mid-West in 2009 resulted in a large increase in numbers of patients undergoing emergency surgery for appendicitis in University Hospital Limerick (UHL). AIMS: The aim of this study was to assess the impact of reconfiguration on the management of appendicitis in this area. METHODS: Data on all patients who underwent appendicectomy between January and June 2007 were compared with the corresponding data from January to June 2011. The numbers of operations, types of operations, lengths of stay (LOS), operation start times, rates of negative histology specimens and readmissions within 30 days were compared. One hundred and twenty-five appendicectomies [48 laparoscopic (38.4 %)] were performed in the 2007 group of which 32 specimens (25.6 %) were histologically negative. Three hundred and nineteen appendicectomies [238 laparoscopic (74.6 %)] were performed in the 2011 group of which 62 specimens (19.4 %) were histologically negative. The increase in numbers of laparoscopic procedures was significant (p < 0.001). The reduction in the negative appendicectomy rate was not statistically significant (p = 0.16). There were 10 conversions (20.8 %) to open surgery in the 2007 period and 12 (5 %) in the 2011 period (p = 0.001). Mean LOS for the 2007 and 2011 groups was 4.45 and 3.16 days (p < 0.001). Six (4.8 %) readmissions within 30 days occurred in the 2007 group with 20 (6.3 %) in the 2011 group (p = 0.66). CONCLUSION: Though reconfiguration of surgical services has resulted in a significant increase in workload, LOS has decreased significantly while maintaining acceptably low negative appendicectomy, conversion and readmission rates.

Inhibition of protein kinase A activity depresses phrenic drive and glycinergic signalling, but not rhythmogenesis in anaesthetized rat.

The cAMP-protein kinase A (PKA) pathway plays a critical role in regulating neuronal activity. Yet, how PKA signalling shapes the population activity of neurons that regulate respiratory rhythm and motor patterns in vivo is poorly defined. We determined the respiratory effects of focally inhibiting endogenous PKA activity in defined classes of respiratory neurons in the ventrolateral medulla and spinal cord by microinjection of the membrane-permeable PKA inhibitor Rp-adenosine 3',5'-cyclic monophosphothioate (Rp-cAMPS) in urethane-anaesthetized adult Sprague Dawley rats. Phrenic nerve activity, end-tidal CO2 and arterial pressure were recorded. Rp-cAMPS in the preBötzinger complex (preBötC) caused powerful, dose-dependent depression of phrenic burst amplitude and inspiratory period. Rp-cAMPS powerfully depressed burst amplitude in the phrenic premotor nucleus, but had no effect at the phrenic motor nucleus, suggesting a lack of persistent PKA activity here. Surprisingly, inhibition of PKA activity in the preBötC increased phrenic burst frequency, whereas in the Bötzinger complex phrenic frequency decreased. Pretreating the preBötC with strychnine, but not bicuculline, blocked the Rp-cAMPS-evoked increase in frequency, but not the depression of phrenic burst amplitude. We conclude that endogenous PKA activity in excitatory inspiratory preBötzinger neurons and phrenic premotor neurons, but not motor neurons, regulates network inspiratory drive currents that underpin the intensity of phrenic nerve discharge. We show that inhibition of PKA activity reduces tonic glycinergic transmission that normally restrains the frequency of rhythmic respiratory activity. Finally, we suggest that the maintenance of the respiratory rhythm in vivo is not dependent on endogenous cAMP-PKA signalling.

Patient satisfaction following emergency admission via a surgical assessment unit and an emergency department.

AIM: Acute surgical patients are admitted to our regional hospital through the emergency department (ED) and through a new surgical assessment unit (SAU). The aim of this study was to compare the efficiency of the two units in seeing and assessing acute surgical patients, as well as patients' satisfaction with their experiences in both units. METHODS: A patient satisfaction scoring questionnaire was distributed to 115 consecutive surgical patients attending the SAU and ED over an 8-week period. Patients' impressions of waiting times, pain management and interactions with staff were detailed. The actual times taken for assessment, admission and discharge were recorded and compared with those perceived by the patients. RESULTS: Patients' perceptions of care were very high within both the ED and the SAU, with 95 % of SAU patients reporting their care as excellent or very good compared with 86 % of ED patients (p = 0.014). Patients were assessed considerably faster in the SAU compared with the ED, with an average wait from registration to admission or discharge totalling 5 h in the SAU compared with 12 h in the ED. CONCLUSION: The SAU provides an effective and efficient mode of assessment of acute surgical patients. While patients were discharged faster from the SAU than the ED, patients rated both units highly in terms of satisfaction with the service provided.

Improving patient care--the first year in a dedicated surgical assessment unit.

A surgical assessment unit (SAU) was established in October 2009 at the Mid-Western Regional Hospital. We assessed this servic in its initial year and compared it to Emergency Department (ED) services. We audited SAU and ED databases and theatre logbooks from November 2009 to October 2010. 1949 patients were referred to the SAU and 857 patients were admitted (44%). Only 44 SAU patients (6%) waited more than 6 hours for a bed compared to 828 patients (68%) admitted through the ED. SAU patients who required emergency surgery had a shorter waiting time before theatre (37 (18.6%) vs 9(6%) waited less than 6 hours, p < 0.05). To summarise, we found that almost 2,000 patients who would otherwise have presented to the ED were referred to the SAU. Waiting times for admission and theatre were significantly shorter. Further resource allocation could expand the service and improve it further, by diverting more patients from the ED.

Vascular trauma in an Irish regional hospital.

BACKGROUND: Vascular trauma is a common cause of mortality and morbidity worldwide. There are few accurate quantitative data available presently on the nature and outcome of these injuries. The aim of this study was to determine the incidence, aetiology, management and outcome of vascular injuries which required surgical intervention at a regional vascular unit. METHODS: All patients who suffered a vascular injury requiring surgical intervention between January 1992 and December 2005 were included. RESULTS: A total of 35 patients who underwent operative intervention for vascular trauma were reviewed. There were 26 men and 9 women with a median age of 26 years (range 3-80 years). Road traffic accidents accounted for 15 (43%) of all cases and 16 patients (47%) had an associated fracture. The brachial artery was most frequently injured, constituting 36% of all cases. Interposition grafting using the autogenous long saphenous vein was the most common procedure performed (11 patients). Eleven patients required a secondary procedure while the overall limb amputation rate was 8.5%. There was one mortality following an IVC injury. Seventy-four per cent of the cohort was asymptomatic at last follow-up. CONCLUSION: While vascular trauma is relatively uncommon in our catchment area it can be successfully managed. Most of the cases occur in young fit patients.

Mobility in patients with venous leg ulceration.

OBJECTIVES: To compare mobility in patients with venous leg ulcers to matched controls and determine the influence of mobility, age and ulcer size on ulcer healing. METHODS: 25 leg ulcer patients, and 25 matched controls wore a mobility monitor (ActivPAL, PAL Technologies Ltd, Glasgow, Scotland)) which recorded the number of steps and amount of time spent walking, standing, sitting or lying for a one-week period. A walking index was calculated. The ulcer group were treated with compression bandaging and ulcer healing recorded over 12 weeks. RESULTS: There were 13 female subjects in each group. The median age was 70.5 (range 30-89) years. There was no difference in the amount of time either group spent standing, walking and resting. There was a significant reduction in the number of steps taken and in the walking index in the ulcer group compared to controls (ulcer group, median 6,685 steps/day, range 2074-17,999; control group median 8750, range 4917-16,043, p<0.05, Mann Whitney u test). Smaller ulcers and ulcers of recent onset were most likely to heal within 12 weeks (p=0.005 and p=0.011 respectively, Chi squared test). The percentage of time spent mobilising and resting did not influence ulcer healing (r(s)=-0.125; p=0.55). CONCLUSIONS: Mobility patterns among patients with leg ulcers are not significantly different to age matched controls. Ulcer patients take fewer steps per week compared to controls indicating they have reduced calf muscle pump function. Further studies are required to determine whether therapies which increase calf muscle activity have a role in ulcer treatment.

Repeated cycles of Clostridium-directed enzyme prodrug therapy result in sustained antitumour effects in vivo.

The unique properties of the tumour microenvironment can be exploited by using recombinant anaerobic clostridial spores as highly selective gene delivery vectors. Although several recombinant Clostridium species have been generated during the past decade, their efficacy has been limited. Our goal was to substantially improve the prospects of clostridia as a gene delivery vector. Therefore, we have assessed a series of nitroreductase (NTR) enzymes for their capacity to convert the innocuous CB1954 prodrug to its toxic derivative. Among the enzymes tested, one showed superior prodrug turnover characteristics. In addition, we established an efficient gene transfer procedure, based on conjugation, which allows for the first time genetic engineering of Clostridium strains with superior tumour colonisation properties with high success rates. This conjugation procedure was subsequently used to create a recombinant C. sporogenes overexpressing the isolated NTR enzyme. Finally, analogous to a clinical setting situation, we have tested the effect of multiple consecutive treatment cycles, with antibiotic bacterial clearance between cycles. Importantly, this regimen demonstrated that intravenously administered spores of NTR-recombinant C. sporogenes produced significant antitumour efficacy when combined with prodrug administration.

Demands for vascular access in a renal dialysis unit: implications for a regional vascular unit.

BACKGROUND: The development of regional dialysis units and the expanding indications for dialysis has led to increased demand for vascular access surgery. Consequently, the provision and maintenance of access, and the management of related complications has created a considerable burden on vascular surgical units in hospitals providing renal replacement therapy (RRT). AIMS: The objectives of our study were to review our experience with a variety of vascular access modalities for haemodialysis and to quantify the associated surgical workload. METHODS: We reviewed our experience in a consecutive group of dialysis patients who had access surgery for RRT in a regional hospital setting. RESULTS: Between January 1995 and January 2000, 69 patients entered the long-term dialysis programme in the Mid-Western region (population = 320,000). Of the 158 procedures performed, 138 (87%) were for access creation, and 20 (13%) related to access revision procedures. Twenty patients (29%) developed a total of 30 access related complications. Vascular access procedures accounted for 10% of the vascular surgical workload (1598 procedures) in the five-year period. CONCLUSION: Vascular access is an important part of the haemodialysis services and surgical expertise should be available at local level to cope with likely demand.

Haemodynamic study examining the response of venous blood flow to electrical stimulation of the gastrocnemius muscle in patients with chronic venous disease.

OBJECTIVES: The aim of this study was to explore the option of stimulating calf muscle contraction through externally applied neuromuscular electrical stimulation (NMES) and to measure venous blood flow response to this stimulation. METHODS: Ten patients with class 6 chronic venous disease (CEAP clinical classification) were recruited. Measurements of peak venous velocities in the popliteal vein were recorded by Duplex scanning in response to six test conditions; 1. Standing, 2. Voluntary calf muscle contraction, 3. Standing with NMES applied, 4. Standing with compression bandaging applied to the leg, 5. Voluntary calf muscle contraction with compression bandaging applied to the leg, 6. Stationary with compression bandaging applied to the leg and NMES applied. Comfort assessment was completed using visual analogue scales at each test stage and on study completion each patient completed a short structured interview to determine comfort and acceptability of NMES. Statistical analyses were carried out using SPSS, Version 9. Non-parametric testing was used in all analyses using the Wilcoxon Signed Ranks Test for paired samples. RESULTS: There was a significant increase in venous velocities on voluntary contraction of the calf muscle (median resting vel 7.3 cm/s; voluntary contraction median 70 cm/s) and with the introduction of NMES, both with compression (median velocity 15 cm/s, p = 0.005 Wilcoxon) and without compression (median velocity 13 cm/s, p = 0.005 Wilcoxon). The greatest increase with NMES was when combined with compression bandaging. All patients reported the stimulus as an acceptable treatment option with 90% reporting NMES as comfortable. CONCLUSIONS: Healing rates in venous ulceration with the application of compression bandaging remain between 50 and 70%. This study shows a positive haemodynamic response to NMES. Further research is needed to quantitatively measure the effect of NMES on ulcer healing.

Local anaesthetic flush reduces postoperative pain and haematoma formation after great saphenous vein stripping--a randomised controlled trial.

OBJECTIVES: To observe the effect of local anaesthetic flush through the great saphenous vein (GSV) tunnel on postoperative pain and haematoma formation following saphenous vein stripping operations. DESIGN: Prospective, double-blind, randomised, control trial. METHODS: One hundred patients were randomized to receive 20 ml of local anaesthetic (bupivacaine 0.25% + adrenaline) or saline control flush through the GSV tunnel after stripping in a double-blind study. Visual analogue pain scores were used to measure postoperative pain daily for the 1st week, then at 3 weeks and 6 weeks. Patients were examined during the 1st, 3rd and 6th week for haematoma formation. RESULTS: In the control group the median postoperative pain score was 4 (range 0-7) in the immediate postoperative period compared to a median of 1 (range 0-4) in the LA group (p<0.001). The median pain score on day-4 was 4 (range 1-6) (control) vs. 1 (range 0-3) (LA group) (p<0.001, Mann-Whitney Utest) and on day-6 it was 1 (range 0-5) (control) vs. 0 (range 0-5) (LA group) (p<0.001, Mann-Whitney). Twelve patients (24%) developed a haematoma in the GSV tunnel in the control group compared to three patients (6%) in the LA group (p = 0.007). CONCLUSION: Flushing of the GSV tunnel with bupivacaine plus adrenaline significantly reduces postoperative pain and haematoma formation in patients undergoing GSV stripping for varicose veins.

A review of technological approaches to venous ulceration.

Leg ulceration is a chronic condition affecting about 1-2% of the adult population. The main causes of leg ulceration are venous hypertension, arterial insufficiency, diabetes, or a combination of these aetiologies (causes) or malignancy. Venous ulcers account for approximately 80% of all leg ulcers and are a result of venous hypertension. The current mainstay of treatment of venous ulcers is the application of graduated compression bandaging to the limb. In spite of the application of the best evidence-based therapy, healing rates for venous leg ulcers remain disappointing, at 50-70% after 12 weeks of treatment, depending on initial size and chronicity of the ulcer. Thus, a large number of ulcers are unhealed by this time, and many patients suffer from long-term leg ulceration, some remaining for years, and those that heal often recur. There is an obvious need to develop new treatments that would improve healing rates. This review provides a complete overview of the anatomy of venous circulation and the physiology pertaining to it, the pathophysiology of venous disease, the pathogenesis of ulceration, and a review of treatments currently employed in healing venous leg ulcers and their supporting evidence. The aim of this article is to encourage a fresh look at this chronic problem and stimulate ideas on how healing rates can be improved.

In vitro cytotoxic activity of Thai medicinal plants used traditionally to treat cancer.

The SRB assay was used to test cytotoxicity against three human cancer cell lines and one normal cell line of 11 Thai medicinal plant species used by traditional doctors in treating cancer patients. The extraction procedures used were similar to those practised by Thai traditional doctors (ethanolic and water extracts). Extracts were tested against the human large cell lung carcinoma cell line COR-L23, the human breast adenocarcinoma cell line MCF-7 and human colon adenocarcinoma cell line LS-174T and normal human keratinocytes SVK-14. The results showed that three plants; Dioscorea membranacea Pierre ex Prain & Burkill, Dioscorea birmanica Prain & Burkill (Dioscoreaceae) and Siphonodon celastrineus Griff. (Celastraceae), exhibited high cytotoxic activity showing a certain degree of selectivity against the different cell types.

Comparison of standard and double reading and computer-aided detection (CAD) of interval cancers at prior negative screening mammograms: blind review.

The study evaluates the role of computer-aided detection (CAD) in improving the detection of interval cancers as compared to conventional single (CONV) or double reading (DOUBLE). With this purpose, a set of 89 negative cases was seeded with 31 mammograms reported as negative and developing interval cancer in the following 2-year interval (false negative (FN)=11, minimal signs (MS)=20). A total of radiologists read the set with CONV and then with CAD. Overall, there were 589 cancer and 1691 noncancer readings with both CONV and CAD. Double reading was simulated by combining conventional readings in all 171 possible combinations of 19 radiologists, resulting in a total of 5301 cancer and 15 219 noncancer readings. Conventional single, DOUBLE and CAD readings were compared in terms of sensitivity and recall rate. Considering all 19 readings, cancer was identified in 190 or 248 of 589 readings (32.2 vs 42.1%, chi(2)=11.80, df=1, P<0.01) and recalls were 287 or 405 of 1691 readings (16.9 vs 23.9%, chi(2)=24.87, df=1, P<0.01) at CONV or CAD, respectively. When considering FN and MS cases separately, sensitivity at CONV or CAD was 50.2 or 62.6% (chi(2)=6.98, df=1, P=0.01) for FN and 22.3 or 30.7% (chi(2)=6.47, df=1, P=0.01) for MS cases, respectively. Computer-aided detection (average of 19 readings) was slightly and not significantly less sensitive (sensitivity: 42.1 vs 46.1%, chi(2)=3.24, df=1, P=0.07) but more specific (recall rate 23.9 vs 26.1%, chi(2)=3.8, df=1, P=0.04) as compared to DOUBLE (average of 171 readings). Average sensitivity for FN cases only was 62.6% for CAD and 64.8% for DOUBLE (chi(2)=0.32, df=1, P=0.58). Corresponding values for MS cases were 30.7% for CAD and 35.7% for DOUBLE (chi(2)=3.53, df=1, P=0.06). Compared to CONV, CAD allowed for improved sensitivity, though with reduced specificity, both effects being statistically significant. Computer-aided detection was almost as sensitive as DOUBLE but significantly more specific. Computer-aided detection might be used in the current practice to improve sensitivity of conventional single reading. Based on estimates of screening sensitivity and FN/MS interval cancer expected frequency, the absolute increase of screening sensitivity expected by introducing CAD-assisted reading may be estimated around 0.9%. The use of CAD as a possible surrogate to conventional DOUBLE needs to be confirmed by further studies, which should include a cost-effective analysis.

Randomized clinical trial and economic analysis of four-layer compression bandaging for venous ulcers.

BACKGROUND: The aim of this study was to compare the cost-effectiveness of four-layer compression bandaging for venous leg ulcers with that of other available treatments. METHODS: In this pragmatic trial, 200 patients with a venous leg ulcer were randomized either to four-layer bandaging (intervention group; n = 100) or to continue their usual system of care (control group; n = 100). The follow-up for each patient was 12 weeks. Analysis was by intention to treat; the main outcome measures were time to healing and cost to the health board per leg healed. RESULTS: Baseline characteristics were well matched in the two groups. The Kaplan-Meier estimate of the healing rate at 3 months was 54 per cent with four-layer bandaging and 34 per cent in the control group. Throughout the 3 months, four-layer bandaging healed leg ulcers significantly earlier (P = 0.006). There was a significant reduction in the median cost per leg healed with four-layer bandaging (euro 210 versus euro 234; P = 0.040). CONCLUSION: Four-layer bandaging is currently the most effective method of treating venous leg ulcers in a community setting.