12 Robieux I, Kumar R, Radhakrishnan S, Koren G. Assessing pain and
`analgesia with a lidocaine-prilocaine emulsion in infants and toddlers
`during venipuncture. J Pediatr 1991; 118: 971-73.
`13 Puglisi CV, Pao J, Ferrara FJ, de Silva JAF. Determination of
`midazolam (Versed R) and its metabolites in plasma by high-
`performance liquid chromatography. J Chromatogr 1985; 344: 199-209.
`14 Burtin P, Daoud P, Jacqz-Aigrain E, Mussat P, Moriette G.
`Hypotension with midazolam and fentanyl in the newborn. Lancet
`1991; 337: 1545-46.
`15 Heikkila J, Arola M, Kanto J, Laaksonen V. Midazolam as adjunct to
`high dose fentanyl anaesthesia for coronary artery bypass grafting
`operation. Acta Anaesthesiol Scand 1984; 28: 683-89.
`16 Ben-Shlomo I, Abd-El-Khalim H, Ezry J, Zohar S, Tverskoy M.
`Midazolam acts synergistically with fentanyl for induction of
`anaesthesia. Br J Anaesth 1990; 64: 45-47.
`17 Crevoisier CH, Ziegler WH, Eckert M, Heizmann P. Relationship
`between plasma concentration and effect of midazolam after oral and
`intravenous administration. Br J Clin Pharmacol 1983; 16: 51-61.
`18 Persson MP, Nilsson A, Hartvig P. Relation of sedation and amnesia to
`plasma concentrations of midazolam in surgical patients. Clin
`Pharmacol Ther 1988; 43: 324-31.
`19 Tolia V, Brennan S, Aravind MK, Kauffman RE. Pharmacokinetic
`and pharmacodynamic study of midazolam in children during
`esophagogastroduodenoscopy. J Pediatr 1991; 119: 467-71.
`
`20 Hartwig S, Roth B, Theisohn M. Clinical experience with continuous
`intravenous sedation using midazolam and fentanyl in the paediatric
`intensive care unit. Eur J Pediatr 1991; 150: 784-88.
`21 Booker PD, Beechey A, Lloyd-Thomas AR. Sedation of children
`requiring ventilation using an infusion of midazolam. Br J Anaesth
`1986; 58: 1104-08.
`22 Shelly MP, Sultan MA, Bodenham A, Park GR. Midazolam infusions
`in critically ill patients. Eur J Anaesthesiol 1991; 8: 21-27.
`23 Reves JG, Samuelson PN, Lewis S. Midazolam maleate induction in
`patients with ischemic heart disease: haemodynamic observations. Can
`Anesth Soc J 1979; 26: 402-09.
`24 Fragen RJ, Meyers SN, Barresi V, Caldweel NJ. Hemodynamic effects
`of midazolam in cardiac patients. Anesthesiology 1979; 51: 172-76.
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`318-20.
`27 Kuban KCK, Epi SM, Volpe JJ. Intraventricular hemorrhage: an
`update. J Intensive Care Med 1993; 8: 157-76.
`28 Vacanti JP, Crone RK, Murphy JD, et al. The pulmonary
`hemodynamic response to perioperative anesthesia in the treatment of
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`1984; 19: 672-78.
`
`Short reports
`
`Transfemoral endoluminal repair of
`abdominal aortic aneurysm with
`bifurcated graft
`
`Traditional open repair of abdominal aortic aneurysm has
`disadvantages. We present our experience of transfemoral
`endoluminal repair with a bifurcated graft system. 29 patients
`with aortic aneurysm over 5·5 cm in diameter and 1 with a
`3·2 cm aneurysm and bilateral iliac stenosis were assessed;
`5 were suitable for the procedure. The operation was
`all the patients, without haemodynamic
`successful
`in
`compromise or major complications. This technique has the
`potential to reduce morbidity and mortality from abdominal
`aortic aneurysm. Further modifications are required to make it
`applicable to most aneurysms.
`
`Endoluminal repair of abdominal aortic aneurysm is a new
`technique for transfemoral graft placement and aneurysm
`exclusion. This minimally invasive approach avoids
`laparotomy, retroperitoneal dissection, and clamping of the
`aorta required for open repair. Instead of being sutured to
`the aorta, the graft is secured by self-expanding metal stents
`deployed under angiographic control. We report use of
`a bifurcated endoluminal graft for abdominal aortic
`aneurysm.
`29 consecutive patients with abdominal aortic aneurysm greater
`than 5cm in diameter and 1 with a 32 cm aneurysm and bilateral
`iliac stenosis were assessed with ultrasound, contrast-enhanced
`computed
`tomography,
`transfemoral
`and
`aortogram.
`Measurements included the distance from the lowest renal artery to
`the neck of aneurysm and to the aortic bifurcation, distance from
`aortic to iliac bifurcation, diameter of aneurysm neck, and
`minimum and maximum diameters ofthe iliac arteries (table). The
`
`650
`
`system we used is suitable for an aneurysm neck up to 25 cm in
`diameter with a minimum neck length of 1cm. The right iliac
`artery has to be straight and open to allow passage of the delivery
`system and the maximum diameter of the iliac limb of the graft
`cannot exceed 1 -5 cm. None of our patients had a non-aneurysmal
`segment of aorta between the aneurysm and aortic bifurcation to
`allow deployment of a straight graft and only 5 (17%) patents were
`found suitable for the bifurcated system. The major reasons for
`unsuitability were short neck (8), wide neck (7), iliac aneurysms (6),
`and wide (2) and too tortuous (2) an iliac artery.
`Modified Gianturco-z-stents (Cook) were used to secure the top
`end of the soft-dacron bifurcated graft (Meadox) in the non-
`aneurysmal infrarenal aorta and the bottom end of the two limbs
`into the common iliac artery. Siremobil 2000 (Siemens) C-armwas
`used for angiographic imaging. The procedure was under general
`anaesthesia in the operating theatre. Both the common femoral
`arteries were exposed and 10 000 U heparin was administered in an
`intravenous bolus before arteriotomy. A transfemoral catheter was
`introduced from the left femoral artery and passed over the aortic
`bifurcation and pulled out of the right common femoral
`arteriotomy with a stone-retrieval basket. The delivery system (an
`inner shaft and an outer sheath containing the graft and stent) was
`introduced through the right common femoral arteriotomy. Care
`was required in deployment of the top stent between the renal
`artery and the aneurysm, by withdrawing the outer sheath with the
`inner shaft stabilised in the correct position by angiographic
`screening. Complete withdrawal of the outer sheath exposed the
`catheter between the left limb of the graft and the inner shaft at the
`right femoral arteriotomy. This catheter was disconnected from
`the inner shaft and sutured to the transfemoral catheter. The left
`graft limb was guided into the left iliac artery as the transfemoral
`catheter was withdrawn from the left femoral arteriotomy. After
`the deployment of both limbs of the grafts, Wallstents (Schneider)
`were used for additional support.
`Bifurcated aorto-iliac grafts were successfully inserted in
`all patients (table). All remained haemodynamically stable
`during operation. 2 patients required extraperitoneal
`exposure of the common iliac on one side to assist accurate
`deployment of the bottom stent. All resumed normal diet
`within 24 hours of the procedure and were mobile within 48
`hours. All remained well at 1-4 months’ follow-up. In 1
`patient the left limb of the graft occluded at 3 months and
`was successfully treated by a femoro-femoral bypass graft.
`The incidence of abdominal aortic aneurysm has
`increased over the past three decades.Nearly 23% of men
`between the ages of 65 and 75 years have abdominal aortic
`
`MEDTRONIC 1021
`
`- 1 -
`
`

`

`*Symptomatic bilateral ostial iliac stenotic disease with coexisting small aneurysm.
`Table: Patients’ details
`
`aneurysm greater than 4 cm in diameter. The overall
`mortality rate of patients in the community with rupture of
`an aortic aneurysm is 85-95 %.3 Although screening is being
`used to detect symptom-less aneurysms before they
`rupture, most surgeons operate only on aneurysms over
`55 cm in diameter; the management of smaller aneurysms
`remains controversia1.4 The reluctance to operate on
`smaller aneurysm is mainly due to the high risk of
`postoperative morbidity and mortality. Patients with aortic
`aneurysm often have generalised arterial disease and
`angiography shows a 47-65% frequency of coronary artery
`disease.5 During open repair, infrarenal abdominal aortic
`cross-clamping increases systemic vascular resistance by
`about 40% and decreases stroke volume and cardiac output
`by 15-35%, with renal hypoperfusion and subsequent
`hypotension during declamping.6 Less invasive techniques
`with lower morbidity and mortality would therefore be of
`value; transfemoral endovascular aneurysm repair is thus
`an important development.
`Parodi et al’ reported the successful use of endoluminal
`transfemoral repair with non-bifurcated grafts in patients
`with abdominal aortic aneurysm. A limitation of their
`technique is that deployment of a straight aorto-aortic graft
`requires a segment of non-aneurysmal aorta above and
`below the aneurysm. Most substantial aneurysms do not
`have such a segment because the aneurysm usually extends
`to the aortic bifurcation. None of our patients was suitable
`for a straight graft. A bifurcated graft can be used in such a
`situation because the limbs of the graft are deployed in
`the unaffected common iliac arteries. The endoluminal
`placement of bifurcated graft used in this study has been
`developed by Chuter8 and its successful clinical use has
`been reported.99
`Endoluminal aortic aneurysm repair takes no longer than
`traditional open repair and experience may shorten the
`procedure.
`require
`postoperative
`Patients
`do
`not
`management in the intensive-care unit. Shorter hospital
`stay and early resumption of normal activities add to the
`potential economic benefit. Transfemoral endoluminal
`aneurysm repair with a bifurcated graft could reduce
`morbidity and mortality from surgery for abdominal aortic
`aneurysm and allow treatment of patients who would not
`tolerate the open procedure.
`However, only limited follow-up is available on our
`patients and it remains to be seen whether this technique
`can prevent rupture of the aneurysm. Further refinement
`involving development of thinner grafts is in progress to
`allow packing of wider grafts into the sheath, to enable
`inclusion of patients with aneurysm neck over 2-5 cm in
`diameter. Also, with further experience, it may be possible
`to deploy the top stent in necks under 1 -5 cm in length. With
`these two improvements, it would be possible to treat most
`patients.
`We acknowledge the contributions made to this study by Dr R H S Gregson
`and Mr G S Makin, University Hospital, Nottingham.
`
`2
`
`3
`
`4
`
`References
`Fowkes FGC, MacIntyre CCA, Ruckley CV. Increasing incidence of
`1
`aortic aneurysms in England and Wales. BMJ 1989; 298: 33-35.
`Collin J, Araujo L, Walton L, Lindsell D. Oxford screening
`programme for abdominal aortic aneurysm in men aged 65 to 74 years.
`Lancet 1988; ii: 613-15.
`Johansson G, Sedenberg J. Ruptured aortic aneurysms: a study of
`incidence and mortality. Br J Surg 1986; 73: 101-03.
`Greenhalgh RM. Prognosis of abdominal aortic aneurysms. BMJ 1990;
`301: 136.
`Hertzer NR. Basic data concerning associated coronary artery disease
`in peripheral vascular patients. Ann Vasc Surg 1987; 1: 616-20.
`Clark NJ, Stanley TH. Anaesthesia for vascular surgery. In:
`Miller RD, ed. Anaesthesia. 4th ed. New York: Churchill Livingstone,
`1994: 1851-95.
`Parodi JC, Plamaz JC, Burone TD. Transfemoral intraluminal graft
`implantation for abdominal aortic aneurysms. Ann Vasc Surg 1991; 5:
`491-99.
`Chuter TAM. Transfemoral aneurysm repair (DM thesis).
`Nottingham: University of Nottingham, 1994.
`Scott RAP, Chuter TAM. Clinical endovascular placement of
`bifurcated graft in abdominal aortic aneurysm without laparotomy.
`Lancet 1994; 343: 413.
`
`5
`
`6
`
`7
`
`8
`
`9
`
`Vascular Surgery, University Hospital, Nottingham, Nottinghamshire
`NG7 2UH, UK (S W Yusuf FRCS, D M Baker FRCS, S C Whitaker FRCR,
`P W Wenham FRCS, B R Hopkinson FRCS); and Department of Surgery,
`Columbia University College of Physicians and Surgeons, New York,
`USA (T A M Chuter DM)
`Correspondence to: Mr S W Yusuf
`
`Smoking and growth rate of small
`abdominal aortic aneurysms
`
`Smoking is an important risk factor for abdominal aortic
`aneurysm. Limiting the growth rate of small aneurysms has the
`potential to prevent them reaching a size at which surgical
`repair is considered. In 43 patients, with small aneurysms,
`growth rates were studied by serial ultrasound over 3 years.
`The median expansion rate of these small aneurysms was
`0·13 cm per year. Growth rates were higher in those who
`continued to smoke (0·16 vs 0·09 cm per year in those who no
`longer smoked, p=0·038).
`Higher growth
`rates were
`significantly correlated with the concentration of serum
`cotinine. Stopping smoking could reduce the growth rate of
`small abdominal aortic aneurysms.
`
`Abdominal aortic aneurysm is common in the elderly.
`Rupture may be the first sign, and that disaster carries a
`fatality rate of over 90% . Many die before admission and of
`those who undergo emergency repair, mortality is over
`40%. Ultrasound screening has been advocated to allow
`elective repair before rupture. It would be better to prevent
`small aneurysms enlarging to a dangerous size. Most
`aneurysms detected by screening are small,4 which provides
`the opportunity to modify risk factors to reduce aneurysm
`growth.
`We have reported the high yield of aneurysms detected by
`ultrasound in patients with peripheral arterial disease.5 43 of these
`patients (median age 72, range 68-78; 33 men) were available for
`serial follow-up of aneurysm size. The median follow-up was 2
`years (range 1-4). The initial aneurysm diameter was under 5 cm in
`
`651
`
`- 2 -
`
`