Paul N. Rogers

Cardiopulmonary responses to treadmill and cycle ergometry exercise in patients with peripheral vascular disease

BACKGROUND Peripheral arterial disease (PAD) presenting as intermittent claudication (IC) is routinely assessed as the distance or time walked to the onset of pain, which often occurs before significant cardiopulmonary stress and is subject to confounding factors such as increased body mass and altered gait. Thus, where exercise-induced cardiovascular stress is desirable, such as in cardiac stress testing or clinical trials, an alternative modality of exercise is required. Cycling will circumvent several of the associated problems of treadmill walking and may provide an alternative preferable method of exercise, although there is limited information on the physiologic response of patients with PAD to cycling. This study compared the peak cardiorespiratory responses and the repeatability of cycling and treadmill exercise in patients with PAD. METHODS Ten men (mean age, 54 +/- 10 years) with stable IC completed two incremental exercise tests to the limit of tolerance on a treadmill and a cycle ergometer after familiarization with the outcome measures of exercise duration, work performed, respiratory gas exchange variables using continuous breath-by-breath measurement, heart rate, and ratings of perceived pain. RESULTS Both methods of exercise assessment revealed high reproducibility in terms of absolute claudication time (treadmill, r = 0.95; cycle, r = 0.91), time to volitional fatigue (treadmill, r = 0.96; cycle, r = 0.91), and cardiopulmonary exercise responses such as the lactate threshold (treadmill, r = 0.95; cycle, r = 0.94), peak heart rate (treadmill, r = 0.94; cycle, r = 0.96), and peak oxygen uptake (treadmill, r = 0.98; cycle, r = 0.87). Cycling induced significantly higher cardiopulmonary responses (peak heart rate, peak carbon dioxide output, peak minute ventilation, and respiratory exchange ratio) than treadmill exercise. There was no difference in time to volitional fatigue or in absolute claudication time between exercise modalities. CONCLUSION These results demonstrate that exercise testing using cycling offers an alternative method of cardiopulmonary testing for patients with IC that is equally reliable and reproducible to treadmill walking. Cycling may be preferable to treadmill exercise because it induces greater cardiopulmonary and metabolic responses and is better tolerated by patients.

Common iliac artery access during endovascular thoracic aortic repair facilitated by a transabdominal wall tunnel.

Purpose: To describe a technique for common iliac artery (CIA) access during endovascular aortic aneurysm repair when unfavorable angulation between the CIA and the delivery sheath precludes direct arterial access. Technique: After retroperitoneal exposure of the CIA, a puncture site is chosen inferolateral to the surgical incision, and an 18-G trocar/cannula is advanced in alignment with the CIA through the anterior abdominal wall or skin of the upper thigh into the retroperitoneal space. Serial dilatation is performed over a guidewire placed through the cannula to create the subcutaneous tract. The trocar/cannula is replaced over the wire, and the CIA is punctured under direct vision. The guidewire is then advanced into the proximal aorta. A CIA arteriotomy is performed and the delivery system introduced over the guidewire through the tunnel into the iliac artery. Conclusions: Retroperitoneal exposure of the CIA with tunneled transabdominal wall delivery of the stent-graft avoids both external iliac artery injury and creation of a temporary access conduit in patients with iliac tortuosity and/or occlusive disease.

Safety in Surgery: Is Selection the Missing Link?

In this article by Paice et al. [1], the authors make a case for using the lessons learned in the selection of air crew to improve the quality of surgical trainees. This comparison of surgery to aviation has been increasingly discussed in health-care circles worldwide. At best, the analogy is only partially correct and I believe we have now reached the limit of its usefulness. The most apparent limitation is that while flying an advanced aircraft can be compared to the performance of a complex surgical procedure, there is much more to being a surgeon than operating. Remember that most patients seen by most surgeons do not have operations. I have two main problems with the ideas expressed in this article. The first is that it assumes that correcting the ‘‘problem’’ of incorrect selection for surgical training will reduce surgical error. So what evidence is there that such alleged faulty selection is responsible for these errors? Will a change in selection policy reduce the subsequent error rate? Or is error a systemic problem? We live in an era of team work (although the team seems to be less important as soon as something goes wrong), so do we believe that altering the selection process for one team member will have a measurable effect on the error rate? In general terms, the incidence of surgical error can presumably be reduced by fostering a risk-averse culture, e.g., if everything is not OK in the preflight check, the aircraft does not fly. In emergency situations, the surgeon often does not have this option, and indeed surgeons currently are the medical individuals who take ‘‘risks’’ out of necessity. Decision-making with incomplete information is what we do. If we extirpate risk-taking, do we promote dithering? The second problem is that the authors suggest moving to different methods of surgical selection without deciding precisely what it is that we are looking for. It is said that a surgeon is an internist (a physician) who operates. The diagnostic, empathetic skills of a medical specialist should also be present in competent surgeons. In addition, the ability to care for postoperative patients and manage their complications and other disappointments in an objective but sympathetic manner is a crucial quality. It is not clear to me that selection of surgeons primarily on the basis of their visual-spatial ability or their coping strategies in a crisis will improve overall surgical care. The ‘‘ideal’’ surgeon is a multiskilled individual, but we have not yet decided what weight to allocate to each of the component abilities of this ideal individual, or how to assess many of them. I agree with the authors that it is likely that each surgical specialty would weight each characteristic differently. A breast surgeon, for example, would need exceptional empathetic skills, while technical ability would be more important in a cardiac or vascular surgeon. I suppose that some relatively simple tests eventually may have a role in excluding some candidates early in training, thus saving time, but comprehensive aptitude testing is a far distant prospect. Finally, the authors seem to assert that academic ability alone is currently the criterion by which career progression is judged. This is manifestly not so. There is still (in the UK at least) an apprenticeship-type assessment that prevents progression if operative technique, or other abilities, are deficient. In any event, it is clear that we should not allow progression if academic ability is below standard; tests of knowledge, however unfashionable, are still necessary and already have the advantage of being objective. Sooner or later, robots will fly airplanes. Robots are already used to perform operations. However, do we want P. N. Rogers (&) Gartnavel General Hospital, Glasgow G12 0YN, Scotland, UK e-mail: pn.rogers@btinternet.com

Does an Information Leaflet About Surgical Site Infection (SSI) Improve Recollection of Information and Satisfaction of Patients? A Randomized Trial in Patients Scheduled for Digestive Surgery

Merle et al. of Rouen, France, report a study from a department of digestive diseases on the value of written patient information, in addition to oral information, on surgical site infection (SSI). They provide thought-provoking findings [1]. The study was designed initially to investigate whether patients’ lack of knowledge of SSI reflected a deficiency in the provision of information or, rather, a failure of recall on the part of the patient. It further attempted to ascertain whether the provision of additional written information on SSI might lead to a better understanding of the problem and might thus improve patient satisfaction. The hope was that a reduction in the likelihood of legal action after any incident of SSI might then follow. The main finding—that satisfaction about information received is improved but with no evidence of improved recall of knowledge about SSI—is difficult to explain. That this improved satisfaction about information received is associated with an increased belief that SSI is always preventable and therefore subsequent legal action is more likely is counterintuitive. As a real-life study reflecting ‘‘normal’’ surgical practice, this study has several useful lessons. The first is that the provision of information to patients is a complex matter that can have unexpected and sometimes deleterious consequences for both patient and surgeon. It is possible to regard the provision of information as having two main purposes: The first is to inform and thus empower the patient; and the second is to protect the surgeon and his or her employing institution from the consequences of a less than perfect outcome. Ideally, these two purposes should be served by a similar approach to information. Sadly, this is often not so. In the sphere of research ethics, for example, we have seen patient information sheets grow to become complex (legal) documents designed more to protect the study sponsors than to inform the participants. In consequence, the value of such a document as a source of information for the study subject is greatly diminished, sometimes to the point of near uselessness. The important matters that should be emphasized become lost in a sea of minor points, included only so the sponsors can say ‘‘you were warned.’’ Information overload is sometimes as bad as no information. In this study, we see that the provision of information has had the opposite effect. The patient has been better informed—although cannot remember it—and is more satisfied but more inclined to sue. This last finding may not, of course, translate into actual legal activity. Examination of the material provided to the patients may give a clue to the reasons for this paradoxical finding. Although the investigators state that one intention was to make it clear that SSI is not always preventable, nowhere in the leaflet do they make that or any similar statement. It seems that we may conclude that it is not sufficient to allow patients to draw their own conclusions. In retrospect, it might have been an improvement to design the leaflet under the following headings.

Vascular Surgery: Linda Hands, Michael Murphy, Michael Sharp, Simon Ray-Chaudhuri. 480 pp, Oxford University Press, 2007, paperback,

This is the first edition of the Vascular Surgery title that forms part of the Oxford Specialist Handbooks in Surgery series. The authors are led by Linda Hands who is Reader in Surgery at the Nuffield Department of Surgery in Oxford. The ‘‘Handbook’’ series of publications from Oxford are a popular format familiar to U.K. doctors. They were initially established as pocket books for training grade doctors to carry around in lab coats in the wards and clinics for easy reference. The range of topics covered has grown is size over the years, and this book is the latest in the Specialist Surgery line. This book is designed for trainee vascular specialists (residents) who need a rapid overview of the subject in a format that is easily accessible and portable (the book measures 105 9 185 9 17 mm and weighs 280 g). The authors suggest that it also might be useful for trainees in other disciplines, including anesthesia, vascular radiology, vascular nursing, and vascular technology. This seems to be a rather hopeful notion. The book attempts to cover the whole of vascular surgery in a very small space. The chapters are written in large part in a lecture note style with lots of bullet points and many subheadings and line drawings. The range of topics extends from an undergraduate description of atheroma and its risk factors to fairly detailed management of aortoenteric fistula and IVC trauma. As might be expected, coverage of this range of subjects is somewhat patchy, but overall the authors have produced a comprehensive work that will help the trainee vascular surgeon in his first few months in post. The style is rather didactic, but this is probably determined by the format of the book. There is little space to debate competing philosophies in a work of this size. The book is clearly the work of enthusiasts for vascular intervention. They have a tendency to quote figures for risk that are at the lower end of the accepted range. Sometimes the necessarily didactic style produces statements that will cause many colleagues to bridle. The book is clearly aimed at the U.K. market and this impression is reinforced by the rather unnecessary use of trade names for sutures. The authors also seem obsessed by providing OPCS4 codes for all the procedures that they describe. Presumably many trainees in the U.K. now have detailed coding duties as part of their routine workload, and this book is designed to lighten that burden. Marketing of this series of ‘‘Handbooks’’ is predicated on the notion that a comprehensive guide that can be carried in the pocket is a valuable tool for the trainee doctor. There are now better options. An electronic version of Rutherford can now be carried on a PDA much smaller and lighter than this book (Oxford University Press now recognizes this in the provision of PDA versions of some handbooks). The authors have generally succeeded in creating a work that is comprehensive, accessible, and portable but unfortunately in this electronic age, it could be a book whose time has gone.

68.50 (amazon.com)

L’ischemia intestinale acuta coinvolge, naturalmente, la regione irrorata dal-l’arteria mesenterica superiore (AMS). L’organo prevalentemente coinvolto e quin-di l’intestino tenue, ma anche il colon destro puo essere interessato– in quanto sempre vascolarizzato dalla AMS. Dell’ischemia del colon, che e molto meno frequente, discuteremo in un capitolo a parte (vedi colite ischemica, Cap. 24).

Ischemia Intestinale acuta

Di solito non e difficile diagnosticare un aneurisma dell’aorta addominale (AAA) fissurato. E tipico in questi pazienti un esordio acuto con dolore lombare, dolore addominale e collasso associato ad ipotensione. All’esame clinico la presenza di una massa addominale puisante conferma la diagnosi. In questo caso, il paziente e portato direttamente in sala operatoria: l’unico ritardo e dovuto alle prove crociate di compatibilita trasfusionale che pero si fa solo in pazienti stabili.

Urgenze dell’aorta addominale

Attualmente, nel mondo occidentale vengono trattate in eiezione moite piu ernie che in passato e, malgrado cio, i chirurghi si trovano spesso a dover trattare ernie inguinali complicate: e importante sapere quindi come agire.