Postoperative surveillance after surgery for colorectal liver metastasis: a cross-sectional study

INTRODUCTION

Colorectal liver metastases (CRLM) are associated with a high recurrence rate after surgery. There is paucity of high-quality evidence regarding the nature and overall benefit of surveillance after hepatectomy for CRLM. As part of a broader programme of research, this study aimed to assess current strategies for surveillance after liver resection for CRLM and outline surgeons' opinions regarding the benefit of postoperative surveillance.

METHODS

An online survey was sent to clinicians performing surgery for CRLM at tertiary hepatobiliary centres in the UK.

RESULTS

There were responses from a total of 23 centres (88% response rate); 15/23 centres used standardised surveillance protocols for all patients. Most centres followed patients up at six months, but there is variation in postoperative surveillance at 3, 9, 18 and beyond 60 months. Patient comorbidities, indeterminate findings on imaging, margin status and assessment of recurrence risk were identified as the major factors influencing personalised surveillance strategies. There was clear clinician equipoise regarding the costs and benefits of surveillance.

CONCLUSION

There is heterogeneity in postoperative follow-up for CRLM in the UK. High-quality prospective studies and randomised trials are necessary to elucidate the value of postoperative surveillance and identify optimal follow-up strategies.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

A modified Delphi process to establish research priorities in hernia surgery

BACKGROUND

Abdominal wall hernia repair is one of the most commonly performed surgical procedures worldwide, yet despite this, there remains a lack of high-quality evidence to support best management. The aim of the study was to use a modified Delphi process to determine future research priorities in this field.

METHODS

Stakeholders were invited by email, using British Hernia Society membership details or Twitter, to submit individual research questions via an online survey. In addition, questions obtained from a patient focus group (PFG) were collated to form Phase I. Two rounds of prioritization by stakeholders (phases II and III) were then completed to determine a final list of research questions. All questions were analyzed on an anonymized basis.

RESULTS

A total of 266 questions, 19 from the PFG, were submitted by 113 stakeholders in Phase I. Of these, 64 questions were taken forward for prioritization in Phase II, which was completed by 107 stakeholders. Following Phase II analysis, 97 stakeholders prioritized 36 questions in Phase III. This resulted in a final list of 14 research questions, 3 of which were from the PFG. Stakeholders included patients and healthcare professionals (consultant surgeons, trainee surgeons and other multidisciplinary members) from over 27 countries during the 3 phases.

CONCLUSION

The study has identified 14 key research priorities pertaining to abdominal wall hernia surgery. Uniquely, these priorities have been determined from participation by both healthcare professionals and patients. These priorities should now be addressed by well-designed, high-quality international collaborative research.

Zero tolerance to sexual harassment in surgical training in the UK

Sexual harassment exists within the surgical training community and environment. This is unprofessional behaviour and the surgical community must raise awareness of it as well as facilitating and encouraging reporting with robust investigation pathways.

Closure of the appendiceal stump in laparoscopic appendectomy: A systematic review of the literature

Background

Closure of the appendiceal stump is a key step performed during laparoscopic appendicectomy. Inadequate management of the appendiceal stump has the potential to cause significant morbidity. Several methods of stump closure have been described, however high-level evidence is limited. We performed a systematic review evaluating clinical outcomes and quality of the evidence for the methods of appendiceal stump closure.

Methods

A systematic literature search was performed using Medline, Embase, Cochrane Database and Google Scholar to identify studies comparing appendiceal stump closure methods in laparoscopic appendectomy for acute appendicitis from inception to October 2019. Data regarding operative duration, peri-operative complications, length of stay and costs were collated from all included studies.

Results

From 160 identified studies, 19 met the inclusion criteria. Endoloops and endoclips provide equivalent clinical outcomes at lower cost, while operative duration was shortest with endoclip closure. Endostapler devices have the lowest rate of peri-operative complications (3.56%), however their cost limits their regular use in many healthcare environments. Post-operative complication rate and length of stay were similar for all stump closure methods. Conclusion: Although there are no significant differences in method of stump closure in laparoscopic appendectomy, closure with endoclips provides the shortest operative duration. There is a need for robust and standardized reporting of cost data when comparing stump closure methods, together with higher level evidence in the form of multi-centre randomized controlled trials before firm conclusions can be drawn regarding the optimal method of stump closure.

•

Currently there is no robust higher order evidence which assesses clinical outcomes, cost and time efficiency of methods of stump closure in laparoscopic appendicectomy.

•

This is the first systematic review to investigate clinical outcomes, cost and quality of current evidence for all methods of laparoscopic appendiceal stump closure in acute appendicitis.

•

No difference was observed in methods of stump closure in complication rate, length of stay, cost, and time efficiency.

•

Endostaplers appear to provide most robust closure, albeit at a higher economic cost.

•

Endoloops appear to provide efficient and successful closure, and are currently the most frequently studied method of closure.

Perineal rectosigmoidectomy for rectal prolapse-the preferred procedure for the unfit elderly patient? 10 years experience from a UK tertiary centre

BACKGROUND

Rectal prolapse is a disease presentation with a prevalence of about 1%, mainly affecting older women. It usually presents with symptoms of rectal mass, rectal bleeding, fecal incontinence or constipation, with patients frequently feeling socially isolated as a result. Perineal rectosigmoidectomy is associated with lesser morbidity and mortality than the abdominal procedure, but with a much higher recurrence rate. Therefore, this technique is mainly suitable for the frail elderly patient. Specific outcomes in an elderly population have been described in only a few studies. We evaluated the morbidity, mortality, recurrence rate and functional results after this procedure related to age.

METHODS

All patients who underwent a perineal rectosigmoidectomy over a 10-year period in two tertiary referral centers were included in the study. American Society of Anesthesiology (ASA) grade, pre- and postoperative symptoms, pathology-reported post-fixation specimen length, length of in-patient stay, 30-day morbidity/mortality, and recurrence were measured.

RESULTS

A total of 45 patients underwent a perineal rectosigmoidectomy. Forty-three (95%) were female, with a median age of 82.0 years (IQR 70.5-86.5), ASA grade III and median follow-up of 20 months (range 8.5-45.5 months). Half of the cohort was over 80 years old. Significant symptomatic relief was achieved, predominantly the resolution of rectal mass (8.9% vs. 60.0% preoperatively), fecal incontinence (15.6% vs. 46.7%) and constipation (4.4% vs. 26.7%). The median length of stay was 6 days, while morbidity occurred in 14 patients (31.1%) and recurrence occurred in 6 patients (13%). There were no deaths within 30 days of the procedure and outcomes were comparable in the < 80 and ≥ 80 age group.

CONCLUSIONS

Perineal rectosigmoidectomy is safe for older patients with greater comorbidities resulting in good functional results and is associated with low morbidity and mortality.

Age at death and the effect of lead-time bias in patients with colorectal cancer: a 10-year follow-up

AIM

Studies addressing the benefit of early intervention are prone to lead-time bias, which results in an artificial improvement in cancer-specific mortality. We have previously compared the age at death for patients with colorectal cancer presenting on an emergency or elective basis. In this study, we aimed to repeat the analysis with a minimum follow-up of 10 years.

METHOD

A nonscreen-detected cohort of patients presenting with colorectal cancer to three Lanarkshire Hospitals between 2000 and 2006 were entered into a prospective database, with analysis performed on 28 November 2016. The following data were collected: age at death, presentation type (emergency/elective), operative intent (palliative/curative) and Dukes stage. Results are presented as [mean (95% confidence intervals)]. Statistical analysis was undertaken using Student's t-test and multivariate analysis performed using Cox proportional hazard models.

RESULTS

One thousand six hundred and thirty-six patients were identified. Elective patients presented younger than emergency patients [67.9 (67.3-68.5) vs 70.9 (69.6-72.2) years; P < 0.0001]. Overall mortality was 71.1% at time of analysis; no difference was seen in the mean age at death between emergency and elective presentation [73.5 (72.4-74.8) vs 73.6 (72.3-74.9) years; P = 0.841].

CONCLUSION

Current early detection strategies to diagnose colorectal cancer may improve cancer-specific survival by increasing lead-time bias. However, in our cohort of symptomatic patients, treatment on an elective or emergency basis does not influence overall survival. These data suggest that in selected patients, particularly where there is comorbidity, it may be reasonable to adopt a more expectant approach to investigate and treat colorectal symptoms.

Systematic review of the use of big data to improve surgery in low- and middle-income countries

Background

Technological advances have led to the generation of large amounts of data, both in surgical research and practice. Despite this, it is unclear how much originates in low‐ and middle‐income countries (LMICs) and what barriers exist to the use of such data in improving surgical care. The aim of this review was to capture the extent and impact of programmes that use large volumes of patient data on surgical care in LMICs.

Methods

A PRISMA‐compliant systematic literature review of PubMed, Embase and Google Scholar was performed in August 2018. Prospective studies collecting large volumes of patient‐level data within LMIC settings were included and evaluated qualitatively.

Results

A total of 68 studies were included from 71 LMICs, involving 708 032 patients. The number of patients in included studies varied widely (from 335 to 428 346), with 25 reporting data on 3000 or more LMIC patients. Patient inclusion in large‐data studies in LMICs has increased dramatically since 2015. Studies predominantly involved Brazil, China, India and Thailand, with low patient numbers from Africa and Latin America. Outcomes after surgery were commonly the focus (33 studies); very few large studies looked at access to surgical care or patient expenditure. The use of large data sets specifically to improve surgical outcomes in LMICs is currently limited.

Conclusion

Large volumes of data are becoming more common and provide a strong foundation for continuing investigation. Future studies should address questions more specific to surgery.

Polymeric clips are a quicker and cheaper alternative to endoscopic ligatures for securing the appendiceal stump during laparoscopic appendicectomy

Introduction The use of polymeric clips in securing the appendiceal stump has been increasingly reported as a viable alternative to current methods in emergency laparoscopic appendicectomy. We evaluated the operative outcomes following the use of polymeric clips versus endoscopic ligatures. The primary endpoint was operative time, with secondary outcomes including complications, inpatient stay, and cost analysis. Materials and methods Operative records were retrospectively analysed to identify patients undergoing laparoscopic appendicectomy between January 2014 and June 2015. Data collected included age, gender, body mass index, duration of surgery, length of hospital stay, antibiotic use, preoperative haematological and biochemical parameters, 30-day readmission rate and complications. Results A total of 125 patients were included within the study, with 78 within the endoloop group and 47 in the polymeric clip group. There were no differences in age, gender, body mass index, hospital stay, antibiotic use, 30-day readmission rates or postoperative complications. Operative time was significantly reduced in the polymeric clip group (59 vs. 68 minutes, P = 0.00751). The use of polymeric clips cost £21 compared with £49 for endoloops per operation, which rose to £70 if both clips and endoloops were used during the procedure. Discussion Polymeric clips are a safe, viable and economical method for securing the appendiceal stump during laparoscopic appendicectomy. The clinical significance of nine minutes of reduced operating time in the polymeric clip cohort warrants further study with an adequately powered randomised controlled trial.

Variability in the prescribing of intravenous fluids: A cross sectional multicentre analysis of clinical practice

AIMS

Intravenous (IV) fluid administration continues to be a mainstay of care in General Surgery. Yet if they are prescribed incorrectly significant morbidity including electrolyte abnormalities, renal impairment and cardiac failure can develop. Despite this, it is frequently the responsibility of the most junior staff to prescribe IV fluids. We aim to analyse the understanding of IV fluid prescribing amongst junior doctors and to describe variability in clinical practice.

METHODS

We undertook a multicentre questionnaire study. Foundation doctors and specialty trainees were invited to undertake a two part paper-based questionnaire. Part one analysed baseline knowledge of the concentration of commonly prescribed fluids. Part two consisted of four clinical vignettes requiring a IV fluid prescribing decision by the surveyed doctor.

RESULTS

A total of 143 Doctors working in 8 hospitals were recruited. 65 (45.5%) doctors correctly stated the daily maintenance fluid requirements of water for an adult (25-30 mls/kg/day), while only 54 (37.8%) knew the sodium concentration of 0.9% NaCl. Lack of postgraduate experience (p = 0.011), qualifying from a medical school outside the United Kingdom (p < 0.0001) and working in one of the eight hospitals in this study (p < 0.0001) were associated with a lower knowledge level. There was limited consensus in prescribing in the responses to the 4 clinical scenarios, with 69 unique combinations of fluid choice, rate and volume prescribed.

CONCLUSIONS

Knowledge of the constituents of common IV fluids and routine requirement for fluid and common electrolytes is poor across junior doctors of all grades, driving large variation in clinical practice.

Systematic review of clinical practice guidelines in kidney transplantation

BACKGROUND

Clinical practice guidelines (CPGs) are widely used to inform the development of protocols for clinical management. Previous work has demonstrated that the quality of CPGs varies widely. This systematic review aimed to determine the quality of CPGs in kidney transplantation in the UK.

METHODS

CPGs in kidney transplantation published between 2010 and 2017 were identified through searches of MEDLINE, NHS NICE Evidence, and websites of relevant UK societies. Using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool, three appraisers rated the quality of CPGs across six domains, the overall quality of each CPG, and whether it should be recommended for future use. Domain scores were calculated, and inter-rater reliability using the intraclass correlation coefficient (ICC) was reported.

RESULTS

Thirteen CPGs met the inclusion criteria. The domain 'clarity of presentation' scored highest, followed closely by 'scope and purpose'. The poorest scoring domains were 'applicability' and 'editorial independence'. Editorial independence also had the widest range of scores. Of the 13 CPGs, one was not recommended for future use, seven were recommended for use with modifications, and five for future use with no need for modification. Mean overall CPG quality was 5 (range 3-6) of a maximum score of 7, and mean inter-rater reliability was substantial with an ICC of 0·71.

CONCLUSION

UK CPGs scored satisfactorily, although with wide variation in how well each domain scored both within and across CPGs. The quality of UK CPGs can still be improved.

Antifungal prophylaxis in liver transplantation: a systematic review and network meta-analysis

Invasive fungal infections (IFIs) cause significant morbidity and mortality in liver transplant recipients, but the need and best agent for prophylaxis is uncertain. A comprehensive literature search was performed to identify randomized controlled trials comparing regimens for antifungal prophylaxis in liver transplant recipients. Direct comparisons were made between treatments using random-effects meta-analysis and a Bayesian network meta-analysis was performed for the primary end point of proven IFI. Fourteen studies met inclusion criteria, reporting comparisons of fluconazole, liposomal amphotericin B (L-AmB), itraconazole, micafungin and placebo. Overall, antifungal prophylaxis reduced the rate of proven IFI (odds ratio [OR] 0.37, confidence interval [CI] 0.19-0.72, p = 0.003), suspected or proven IFI (OR 0.40, CI 0.25-0.66, p = 0.0003) and mortality due to IFI (OR 0.32, CI 0.10-0.83, p = 0.02) when compared to placebo. All-cause mortality was not significantly affected. There was no difference in risk of adverse events requiring cessation of prophylaxis (OR 1.11, 95% CI 0.48-2.55, p = 0.81). In the network meta-analysis an equivalent reduction in the rate of IFI was seen with fluconazole (OR 0.21, CI 0.06-0.57) and L-AmB (OR 0.21, CI 0.05-0.71) compared with placebo. Routine prophylaxis with fluconazole or L-AmB reduces the incidence of IFI following liver transplantation, and the available evidence suggests that the two are equivalent in efficacy.

Systematic review and meta-analysis of hypothermic machine perfusion versus static cold storage of kidney allografts on transplant outcomes

BACKGROUND

Adequate preservation of renal allografts for transplantation is important for maintaining and improving transplant outcomes. There are two prevalent methods: hypothermic machine perfusion and static cold storage. The preferred method of storage, however, remains controversial. The objective was to review systematically the evidence comparing outcomes from these two modalities.

METHODS

A literature search was performed using MEDLINE, Embase, the Cochrane Library, the Transplant Library and the International Clinical Trials Registry Platform. The final date for searches was 30 November 2012. Studies were assessed for methodological quality. Summary effects were calculated as relative risk (RR) with 95 per cent confidence interval (c.i.). Randomized clinical trials (RCTs) and non-RCTs were included, but evaluated separately. Results from RCTs alone were used for meta-analysis.

RESULTS

Eighteen studies met the inclusion criteria, including seven RCTs (1475 kidneys) and 11 non-RCTs (728 kidneys). The overall risk of delayed graft function was lower with hypothermic machine perfusion than static cold storage (RR 0·81, 95 per cent c.i. 0·71 to 0·92; P = 0·002). There was no difference in the rate of primary non-function (RR 1·15, 0·46 to 2·90; P = 0·767). There was a faster initial fall in the level of serum creatinine with hypothermic machine perfusion in two RCTs, but not in another. There was no relationship between rates of acute rejection or patient survival and the method of preservation.

CONCLUSION

Data from the included studies suggest that hypothermic machine perfusion reduces delayed graft function compared with static cold storage. There was no difference in primary non-function, acute rejection, long-term renal function or patient survival. A difference in renal graft survival is uncertain.

Allopregnanolone protects against dopamine-induced striatal damage after in vitro ischaemia via interaction at GABA A receptors

Sex steroid hormones, such as progesterone, have been shown to display neuroprotective properties after various models of central nervous system injury, including cerebral ischaemia, although the mechanism(s) of action remain largely undetermined. Allopregnanolone, an active progesterone metabolite, may explain some of the protective actions of progesterone. We utilised an in vitro model of ischaemia to evaluate the neuroprotective potential of allopregnanolone and examine its interaction at the GABA(A) receptor, which is hypothesised to be its main neuroprotective mechanism. In adult male mouse coronal caudate slices exposed to oxygen glucose deprivation (OGD), we measured aspects of OGD-induced dopamine release, which is neurotoxic during ischaemia, using fast cyclic voltammetry and also assessed tissue viability. The GABA(A) agonist, muscimol, displayed a neuroprotective profile in terms of delaying the OGD-evoked dopamine efflux (P < 0.05) and reducing the amount of dopamine released after OGD (P < 0.05). Allopregnanolone, at a concentration of 10(-6)  m, also displayed a neuroprotective profile because it significantly reduced the amount of dopamine efflux (P < 0.05) and reduced the loss of viable tissue after OGD compared to slices exposed to vehicle during OGD (P < 0.05). However, the effect of 10(-6)  m allopregnanolone on dopamine efflux was prevented in the presence of bicuculline, a competitive GABA(A) receptor antagonist. These results describe the use of an in vitro model of ischaemia with respect to determining that allopregnanolone is neuroprotective during the acute phase of ischaemia, and also demonstrate that such actions are dependent, at least in part, upon interaction at the GABA(A) receptor.

Preservation solutions for static cold storage of kidney allografts: a systematic review and meta-analysis

Static cold storage is the most prevalent method for renal allograft preservation. Several solutions have been designed to counteract the detrimental effects of cold ischemia and reperfusion. The aim of this study was to appraise the evidence for the currently available preservation solutions. We performed a systematic literature search using MEDLINE, EMBASE, the Cochrane Library, the Transplant Library and trial registries. Inclusion criteria specified any comparative, prospective study for deceased donor renal allografts. Studies were assessed for methodological quality. The primary outcome was delayed graft function (DGF). Fifteen trials with a total of 3584 kidneys were included. Eurocollins was associated with a higher risk of DGF than University of Wisconsin solution (UW) in two randomized controlled trials (RCTs) and histidine-tryptophan-ketoglutarate (HTK) in two RCTs. UW was associated with an equal risk of DGF compared with Celsior in three RCTs and HTK in two RCTs. There was limited data regarding other comparisons and outcomes. The choice of preservation solution has an effect on the incidence of DGF, which might, in turn, affect long-term outcomes. Both UW and HTK have lower rates of DGF than Eurocollins. There is no difference in the incidence of DGF with the use of Celsior, HTK and UW. These findings are supported by registry data.

Role of transplantation in the management of hepatic malignancy

Background

The acceptance of liver transplantation in the management of hepatic malignancy declined after early poor outcomes. Despite recent developments, including stricter selection criteria and improved adjuvant therapies, the role of liver transplantation in the management of cancer remains controversial. This review explores the evidence for the current role of liver transplantation in the management of hepatic malignancy in the context of recent advances in surgical resection and non-surgical treatments.

Methods

A literature search was conducted using the Cochrane Library and Ovid MEDLINE and EMBASE, using terms for hepatic malignancy and interventions that included liver transplantation, percutaneous interventions, chemotherapy and surgical resection.

Results and conclusion

In patients with primary hepatocellular carcinoma, improved selection has led to outcomes equivalent to those from surgical resection and comparable to those in patients transplanted for non-malignant indications. Recent studies suggest that selection criteria may be refined further. Surgical resection or percutaneous therapies may reduce the risk of progression while waiting for a transplant. Recent improvements have occurred in neoadjuvant therapies for cholangiocarcinoma. Nevertheless, a number of questions regarding the role of liver transplantation for hepatic malignancy remain.

Prevalence of occult metastatic disease in patients undergoing 18F-FDG PET for primary diagnosis or staging of lung carcinoma and solitary pulmonary nodules

BACKGROUND

Accurate staging of lung cancer is essential in determining the most appropriate management plan, as detection of occult metastasis can significantly alter management.

AIMS

The aims of this study are to determine the prevalence of occult metastasis in patients undergoing 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET) for evaluation of suspected/proven lung carcinoma and correlate pre-PET TNM stage with prevalence of metastasis.

METHODS

FDG-PET, which identified patients with metastasis on institutional database, was re-evaluated by a nuclear medicine physician blinded to clinical information. The confidence level of metastasis was scored on a 5-point scale, with a score of >/=4 considered positive.

RESULTS

There were 67 of 645 (10%) patients identified with suspected occult metastasis on FDG-PET. Twelve patients scoring </=3 were excluded. Prevalence of occult metastasis was 10/156 (6%) in solitary pulmonary nodules (SPN); 22/319 (7%) and 23/170 (14%) in proven and suspected lung cancer, respectively. Positive predictive value of FDG-PET for metastasis was 8/10 (80%) in solitary pulmonary nodules, 14/20 (70%) and 17/21 (81%) in proven and suspected lung cancer, respectively. (18)F-FDG-avid lesions classified as false positives were patients with cholelithiasis, rib fractures and those with equivocal/negative bone scans or computed tomography on follow up. There was a higher incidence of true positive occult metastasis in patients in all stages of disease, particularly stage III disease.

CONCLUSION

(18)F-FDG PET is predictive for occult metastatic disease in patients with solitary pulmonary nodules and proven or suspected lung cancer and is more likely to be present in all stages, particularly in stage III. PET findings should be actively pursued with correlative investigation to identify benign pathology in patients who remain candidates for curative treatment.

Efficacy study of video-assisted thoracoscopic surgery pleurodesis for spontaneous pneumothorax

BACKGROUND

This study aims to assess the efficacy of video-assisted thoracoscopic surgery pleurodesis in the treatment of spontaneous pneumothorax with particular reference to the rate of recurrence after abrasion pleurodesis and postoperative neuralgia.

METHODS

One hundred one patients who underwent 109 video-assisted thoracoscopic surgery pleurodesis procedures in the Austin & Repatriation Medical Centre between January 1992 and June 1998 were identified from a computerized database. The follow-up period was from 8 months to 7 years and 1 month (mean, 44.4 months). Patients were telephoned and asked as to whether recurrence occurred, and if so, when it occurred and how it was treated. They were asked to grade their current pain level from 0 to 6.

RESULTS

Eighty-two patients were contacted, corresponding to 88 video-assisted thoracoscopic surgery pleurodesis procedures that were followed up (80.7%). There were five recurrences (5.7%). The pain level was rated as 0 in 64 cases (72.7%), 1 in 27 cases (23.9%), 2 in 1 case (1.1%), and 3 in 2 cases (2.3%).

CONCLUSIONS

These data suggest that video-assisted thoracoscopic surgery pleurodesis is a valid alternative to thoracotomy with pleurectomy for treatment of spontaneous pneumothorax with an acceptable recurrence rate and minimal amount of postoperative neuralgia.

F-18 fluorodeoxyglucose positron emission tomography in the non-invasive staging of non-small cell lung cancer

OBJECTIVE

Positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG), a glucose analogue, as a metabolic tumour marker, has been proposed for the non-invasive staging of oncological disease. Tumours demonstrate increased glycolytic activity and thereby, FDG PET can differentiate benign from malignant lesions. To determine its role in the mediastinal staging of patients with suspected non-small cell lung cancer, a prospective study of FDG PET and computed tomography (CT) compared to surgery and pathology was performed. The analysis group consists of 50 patients, 37 men and 13 women, mean age 64 years (range, 41-78 years).

METHODS

A nuclear physician, blind to the clinical and CT data, graded the FDG PET studies qualitatively on a five-point scale, based on the intensity of glucose uptake, for the presence of mediastinal nodal tumour involvement. Scores of four or greater were considered positive for tumour. An experienced radiologist interpreted the patients' CT scans blind to the other data. The CT criterion for tumour involvement was a nodal long axis diameter of 10 mm or greater. All patients underwent either thoracotomy or mediastinoscopy to obtain surgical specimens. The PET, CT, surgery and pathology were mapped according to the American Thoracic Society nodal classification resulting in 201 nodal stations evaluated. The imaging studies were analysed for N2 or N3 tumour involvement compared to histology or dissection of nodal stations.

RESULTS

All patients had proven non-small cell lung carcinoma. PET excluded tumour in 175 of 181 nodal stations (specificity 97%) compared to 162 of 181 (specificity 90%) by CT. PET correctly identified 16 of 20 (sensitivity 80%) nodal stations with tumour compared to 13 of 20 by CT (sensitivity 65%). Overall, PET correctly staged 191 of 201 nodal stations (accuracy 95%) compared to 175 of 201 by CT (accuracy 87%). By the McNemar test, PET was significantly more specific than CT in excluding nodal tumour involvement (X2 = 5.5, P < 0.05).

CONCLUSIONS

FDG PET is more specific than computed tomography in the non-invasive mediastinal staging of non-small cell lung cancer and has an important clinical role in the pre-operative staging of lung cancer patients.

VATS plication of diaphragmatic eventration

Diaphragmatic eventration in the adult may be associated with dyspnoea. Video-assisted thoracoscopic surgery (VATS) techniques have been applied to the plication of diaphragmatic eventration in three adult patients. Symptoms and spirometry improved in all patients. Ventilation and perfusion of the affected lung was also improved.

The contribution of 18F-fluoro-2-deoxy-glucose positron emission tomographic imaging to radiotherapy planning in lung cancer

A retrospective analysis was performed to determine whether coronal thoracic [18F]fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) scans, if viewed at the time of radiotherapy (RT) planning, would have influenced the anterior-posterior (AP) RT volumes that were administered to a group of unoperated lung cancer patients. Viewing of PET and diagnostic images enabled a qualitative assessment of whether abnormal thoracic PET activity was present in areas regarded as normal by diagnostic imaging; this would, therefore, have influenced the RT volume if done prospectively. Additionally a method of graphical co-registration was devised to quantitate the adequacy of coverage of each patient's abnormal PET activity by his/her actual RT field. Of 15 patients analyzed, 26.7% (four patients) would have had their RT volume influenced by PET findings, highlighting the potential value of PET in treatment planning.

Respiratory responses to CO2 rebreathing in lung transplant recipients

To evaluate the respiratory responses after lung transplantation, we studied the hypercarbic ventilatory response in 20 patients with severe obstructive pulmonary disease and compared it with that of 10 normal subjects. Eleven patients underwent bilateral lung transplantation and 9 patients had single-lung transplantation. All patients had preoperative hypercapnia (51.3 +/- 9.7 mm Hg) and blunted slopes of CO2 rebreathing curves for minute ventilation (0.39 +/- 0.20 L.min-1.mm Hg-1) and inspiratory occlusion pressure (0.35 +/- 0.30 s-1). The hypercapnia and blunted ventilatory responses persisted at the initial postoperative test (5.8 +/- 2.0 days) despite improved pulmonary function (preoperative forced expiratory volume in 1 second [FEV1], 0.57 +/- 0.16 L; initial postoperative FEV1, 1.83 +/- 0.65 L; p < 0.001). By the 15th to 30th postoperative day (21.3 +/- 6.0 days), compared with preoperative and initial postoperative values, end-tidal CO2 had normalized (40.6 +/- 6.9 versus 51.3 +/- 9.7 and 49.6 +/- 10.3 mm Hg; p < 0.005) and was coupled with enhanced ventilatory responses for the rebreathing curve for minute ventilation (1.26 +/- 0.7 versus 0.39 +/- 0.20 and 0.32 +/- 0.32 L.min-1.mm Hg-1; p < 0.005) and the inspiratory occlusion pressure curve (0.98 +/- 7.4 versus 0.35 +/- 0.30 and 0.41 +/- 0.29 s-1; p < 0.005). These respiratory responses developed without a change in postoperative pulmonary function (initial postoperative FEV1, 1.83 +/- 0.65 L versus last postoperative FEV1, 1.96 +/- 0.66 L; p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Tidal volume and respiratory rate changes during CO2 rebreathing after lung transplantation

To evaluate the contribution of the respiratory pattern to the ventilatory response after lung transplantation, we studied the changes in minute ventilation, tidal volume, and respiratory rate during CO2 rebreathing in 14 patients with severe obstructive pulmonary disease, and compared them with 10 normal subjects. Seven patients underwent a bilateral lung transplantation and 7 patients had single-lung transplantation. Single-lung transplant recipients increased their respiratory rate by the last postoperative test compared with either preoperative or initial test periods (0.38 +/- 0.13 versus 0.027 +/- 0.24 or 0.12 +/- 0.08 breaths.min-1.mm Hg-1; p < 0.005). Bilateral lung transplant recipients showed a diminished ability to augment their respiratory rate by the last postoperative test compared with either preoperative or initial test periods (0.13 +/- 0.23 versus 0.54 +/- 0.25 or 0.25 +/- 0.29 breaths.min-1.mm Hg-1; p < 0.06). The restored ventilatory response by the fourth postoperative week was due to a statistically significant increase in tidal volume for both single and bilateral lung transplant recipients. This study demonstrates that when lung transplant recipients have an appropriate ventilatory response to CO2 rebreathing, single-lung transplant recipients have a respiratory pattern similar to normal; whereas the bilateral lung transplant recipients show the effects of total pulmonary denervation. We conclude that the preserved ventilatory response in lung transplant recipients is composed of a respiratory pattern that is influenced by the presence or absence of vagal inputs.

Management of dysfunction in the transplanted lung: experience with 7 clinical cases. Washington University Lung Transplant Group

In a series of 34 lung transplant patients, donor lung dysfunction occurred on 7 occasions. One patient underwent retransplantation and the remaining 6 were treated conservatively. Survival was 100% in the donor lung dysfunction group. Percent predicted forced expiratory volume in 1 second, carbon monoxide diffusion, room air oxygen tension, and distance walked in 6 minutes were all lower (p less than 0.05) at 1 month after transplantation in those patients with donor lung dysfunction as compared with those without. These differences were not significant at 3 months after transplantation. We conclude that donor lung dysfunction can usually be managed conservatively with satisfactory results. Longer follow-up of this group of patients will be necessary to determine the long-term consequences of early graft injury.

Lung transplantation. Analysis of thirty-six consecutive procedures performed over a twelve-month period. The Washington University Lung Transplant Group

A consecutive series of 36 lung transplant procedures in 35 patients, performed over a 12-month period, has been reviewed. There were 14 men and 21 women undergoing 23 single, 12 bilateral, and one en bloc double lung transplant. There were one hospital death and three late deaths in the series, giving a hospital survival rate of 97.2% and a 1-year actuarial survival figure of 91.7%. Airway complications occurred in six patients (17.2%), one of whom died. Cytomegalovirus infection was demonstrated in 18 patients (51%), but no deaths have resulted. The most common cardiac complication was an atrial tachyarrhythmia (nine patients, 25.7%) and three patients had a cardiac arrest, but all were successfully resuscitated. Twelve patients required a further 25 surgical procedures after transplantation; however, renal and hematologic complications were uncommon. The prevalence and management of the other associated complications is discussed.