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[1984-1994: Ten years of skin flaps. Prefabricated flaps].

The term prefabrication of flaps corresponds to completely different technical modalities, often complementary and associated, which share the common feature of extending the indications and potential of pedicle or free flaps. Current methods of prefabrication of flaps can be considered to be based on one or several basic principles of reconstructive surgery. The authors discuss and analyse various modalities: a free flap can be made autonomous or can be expanded prior to transfer. A transfer can be initially prefabricated at its donor site by performing several operative steps in situ. A free transfer can be performed on the main vascular axis of a flap which is subsequently transferred, for example: free scalp transfer to reconstruct an eyebrow on a donor site reconstructing half of the face, but the first in situ operative phase usually consists of performing cutaneous, bone, cartilaginous or even alloplastic material transplants. The transfer is only performed after a sufficiently satisfactory complex anatomical, functional or esthetic unit has been achieved, in order to avoid difficult or dangerous remodeling operations after transfer. The most revolutionary appearance in the area of prefabrications is certainly induction of a pedicle or free neoflap in a so-called random territory. The addition of an arteriovenous pedicle associated with fascia underneath a muscle, underneath a skin cover, in contact with an osteoperiosteal segment allows a perfectly transferable neovascularized unit to be obtained after several weeks. All of the procedures described: autonomization before transfer, expansion before transfer, in situ prefabrication of a complex unit by addition of several tissue units (autologous or alloplastic) in one or several stages and finally vascular induction of a muscular, cutaneous or bone unit, etc. by transfer of a vascular axis in contact with this anatomical structure and combinations of these various modalities obviously open up a new approach which will considerably extend the already remarkable possibilities offered by free tissue transfers.

Adult↗

The Current Status of Thoracoscopic Surgery.

Video-assisted thoracic surgery is increasingly being applied to treat a variety of intrathoracic disease processes. Numerous pleural, pulmonary, esophageal, autonomic nervous system, spinal, and even cardiac procedures are now being performed using this minimally invasive approach. An overview of these thoracoscopic interventions is the focus of this review. It must be realized that although the technical feasibility of these operations has been demonstrated, their role in the practice of general thoracic surgery remains to be defined by critical scientific comparisons with established standards.

Journal Article↗

Optimizing the medical management of diabetic patients undergoing surgery.

Patients with diabetes are prone to metabolic derangements because of their lack of effective insulin. Comorbid conditions, such as coronary artery disease, nephropathy, and autonomic neuropathy warrant preoperative assessment to ensure safety in the perioperative period. Preoperative evaluation must include assessment of chronic complications of diabetes. A thorough history and physical should guide preoperative testing which should be aimed at detecting correctable abnormalities and assessing the extent of end-organ disease. Surgery poses special challenges to patients with diabetes because the stress response, interruption of food intake, altered consciousness, and circulatory alterations all lead to unpredictable glucose and electrolyte levels. The management of insulin perioperatively depends on the preparation normally taken by the patient, and the glucose level on the morning of surgery. The goal is to avoid hypoglycemia and extreme hyperglycemia. Oral hypoglycemic agents should be held on the morning of surgery. Metformin should be discontinued 48 hours prior to and subsequent to surgery in order to reduce the risk of lactic acidosis. The avoidance of hypoglycemia and excessive hyperglycemia intraoperatively is best achieved with frequent monitoring of blood glucose and treating abnormalities according to patients' preoperative regimen and current condition. Maintaining blood glucose levels below 110 mg/dL reduces morbidity and mortality in critically ill patients. Measure blood glucose immediately following surgery because progression of the stress response postoperatively, in addition to possible nausea and vomiting, can complicate the patient's management. Precautions should be taken to prevent damage to peripheral nerves while diabetics are on the operating table because their nerves and limbs are already vulnerable to pressure and stretch injuries secondary to neurologic and vascular disease. With thorough and careful management, metabolic control in the perioperative period is a goal that is attainable for most patients.

Diabetes Complications↗

[Heart rate variability preceding the onset of atrial fibrillation].

BACKGROUND: The occurrence of paroxysmal atrial fibrillation is related to changes in autonomic tone. Vagally mediated atrial fibrillation predominantly occurs at night in young male patients without history of structural heart disease. In contrast, sympathetically mediated atrial fibrillation is typically triggered by stress. ANALYSIS OF HEART RATE VARIABILITY: Heart rate variability usually measured by Holter monitoring can determine changes in autonomic tone immediately preceding the onset of atrial fibrillation. Studies on this topic found divergent results on the incidence of atrial fibrillation mediated by changes in autonomic tone. Dependent on the results of different studies, night-time episodes of idiopathic atrial fibrillation either are vagally or sympathetically mediated. A sympathetic predominance is found in patients after coronary bypass surgery, concordantly. The inconsistency of these findings points to the fact that not only one mechanism, but more complex changes in autonomic tone are responsible for the occurrence of atrial fibrillation in many cases. In modern pacemakers and implantable cardioverter-defibrillators, PP or RR intervals can be stored automatically before the onset of an arrhythmia. By use of these stored intervals, time-domain parameters of heart rate variability can be calculated. We determined changes in short-term heart rate variability (10-second intervals) by analyzing 26 episodes of PP intervals sampled over the last 2 minutes before onset of atrial fibrillation by a modern dual chamber pacemaker. We observed a significant increase of the standard deviation of PP intervals (SDNN10s) as well as of the mean square route of the squared PP intervals (rMSSD10s) within the last 10-second interval before onset of atrial fibrillation (p < 0.05). This finding points to changes in autonomic tone-immediately preceding the onset of atrial fibrillation. CONCLUSION: The preliminarity of these findings and the use of yet not validated short intervals for determination of heart rate variability does not allow to draw pathogenetic or even therapeutic conclusions from these findings.

Adult↗

An artificial somatic-autonomic reflex pathway procedure for bladder control in children with spina bifida.

PURPOSE: Neurogenic bladder is a major problem for children with spina bifida. Despite rigorous pharmacological and surgical treatment, incontinence, urinary tract infections and upper tract deterioration remain problematic. We have previously demonstrated the ability to establish surgically a skin-central nervous system-bladder reflex pathway in patients with spinal cord injury with restoration of bladder storage and emptying. We report our experience with this procedure in 20 children with spina bifida. MATERIALS AND METHODS: All children with spina bifida and neurogenic bladder underwent limited laminectomy and a lumbar ventral root (VR) to S3 VR microanastomosis. The L5 dorsal root was left intact as the afferent branch of the somatic-autonomic reflex pathway after axonal regeneration. All patients underwent urodynamic evaluation before and after surgery. RESULTS: Preoperative urodynamic studies revealed 2 types of bladder dysfunction- areflexic bladder (14 patients) and hyperreflexic bladder with detrusor external sphincter dyssynergia (6). All children were incontinent. Of the 20 patients 17 gained satisfactory bladder control and continence within 8 to 12 months after VR microanastomosis. Of the 14 patients with areflexic bladder 12 (86%) showed improvement. In these cases bladder capacity increased from 117.28 to 208.71 ml, and mean maximum detrusor pressure increased from 18.35 to 32.57 cm H2O. Five of the 6 patients with hyperreflexic bladder demonstrated improvement, with resolution of incontinence. Urodynamic studies in these cases revealed a change from detrusor hyperreflexia with detrusor external sphincter dyssynergia and high detrusor pressure to nearly normal storage and synergic voiding. In these cases mean bladder capacity increased from 94.33 to 177.83 ml, and post-void residual urine decreased from 70.17 to 23.67 ml. Overall, 3 patients failed to exhibit any improvement. CONCLUSIONS: The artificial somatic-autonomic reflex arc procedure is an effective and safe treatment to restore bladder continence and reverse bladder dysfunction for patients with spina bifida.

Adolescent↗

Friction of the gliding surface. Implications for tendon surgery and rehabilitation.

Finger flexor tendon rehabilitation has come a long way, but further advances are possible. Ideally, a healing tendon should move, but under the minimum load necessary to achieve motion. It is possible to design suture repairs that minimize the friction between tendon and sheath while simultaneously maintaining adequate strength to provide a wide margin of safety during therapy. A looped, four-strand modified Kessler repair is a good example of this type of high-strength, low-friction repair. At the same time, rehabilitation methods can also be optimized. A new modified synergistic motion protocol is described in which wrist flexion and finger extension is alternated with wrist and metacarpophalangeal joint extension and finger interphalangeal joint flexion. Based on evidence from basic science studies, the authors hypothesize that this new protocol will deliver more effective proximal tension on the tendon repair than either passive flexion/active extension or synergistic protocols, and may be useful in patients who are not ready for, or are not reliable with, active motion or place and hold protocols. The scientific basis for these new methods is reviewed, and the concept of the "safe zone" for tendon loading, in which tendon motion occurs without gapping of the repair site, is developed.

Biomechanical Phenomena↗

Adrenal medulla grafts produce blood-brain barrier dysfunction.

The results of this study show that grafts of adrenal medulla into the rat brain parenchyma or ventricle produced significant blood-brain barrier dysfunction. Systemically administered protein rapidly entered either the grafts, the surrounding brain tissue or the cerebrospinal fluid. The grafted chromaffin cells avidly took up blood-borne radiolabelled amine. Thus, autonomic tissue transplants prevented normal reconstruction of the blood-brain barrier after surgery and indefinitely exposed host brain tissue to blood-borne compounds.

Adrenal Medulla↗

Adrenal vein sampling: how to make it quick, easy, and successful.

Adrenal vein sampling has a reputation as a difficult procedure. However, it is being performed more frequently at some institutions due to the realization that primary aldosteronism is more common than previously believed. At the author's institution, adrenal vein sampling with computed tomographic (CT) and laboratory correlation has been performed more than 800 times in the past 10 years. Adrenal vein sampling is used to determine whether autonomous hormone production is unilateral or bilateral; unilateral secretion can be treated with surgery. The venous drainage of each adrenal gland is predominantly via a central vein. Recognition of the right adrenal vein is the crux of adrenal vein sampling. CT is useful in planning adrenal vein sampling by demonstrating the anatomy and positions of the adrenal veins. A small amount of contrast material is injected gently and slowly into the adrenal vein; it is not necessary to perform formal venography to outline the entire gland. To confirm that the vein is draining the majority of adrenal cortical blood, the adrenal vein sample should have a significantly higher level of cortisol than a peripheral sample. Adrenal glands that are producing aldosterone demonstrate an aldosterone-cortisol ratio that is higher than the peripheral value.

Adrenal Glands↗

Disability evaluation in children with hemidecorticectomy: use of the activity scales for kids and the pediatric evaluation disability inventory.

The purpose of this study is to investigate the level of disability of children who are either candidates for or have undergone a hemidecorticectomy. The Activity Scales for Kids and the Pediatric Evaluation Disability Inventory were demonstrated to be useful measurement tools yielding comparative results between subgroups. Overall, children with congenital disease seemed less autonomous postoperatively than were preoperative patients or children with acquired disease. Age at surgery and the interval between seizure onset and surgery are potentially important predictors of disability. This could reflect the importance of timing of surgery, development, environment, and possibly brain plasticity processes in this population.

Adolescent↗

Angiotensin and baroreflex control of the circulation.

There is a close association between the location of angiotensin (Ang) receptors and many important brain nuclei involved in the regulation of the cardiovascular system. The present review encompasses the physiological role of Ang II in the brainstem, particularly in relation to its influence on baroreflex control of the heart and kidney. Activation of AT1 receptors in the brainstem by fourth ventricle (4V) administration to conscious rabbits or local administration of Ang II into the rostral ventrolateral medulla (RVLM) of anesthetized rabbits acutely increases renal sympathetic nerve activity (RSNA) and RSNA baroreflex responses. Administration of the Ang antagonist Sarile into the RVLM of anesthetized rabbits blocked the effects of Ang II on the RSNA baroreflex, indicating that the RVLM is the major site of sympathoexcitatory action of Ang II given into the cerebrospinal fluid surrounding the brainstem. However, in conscious animals, blockade of endogenous Ang receptors in the brainstem by the 4V AT1 receptor antagonist losartan resulted in sympathoexcitation, suggesting an overall greater activity of endogenous Ang II within the sympathoinhibitory pathways. However, the RSNA response to airjet stress in conscious rabbits was markedly attenuated. While we found no effect of acute central Ang on heart rate baroreflexes, chronic 4V infusion inhibited the baroreflex and chronic losartan increased baroreflex gain. Thus, brainstem Ang II acutely alters sympathetic responses to specific afferent inputs thus forming part of a potentially important mechanism for the integration of autonomic response patterns. The sympathoexcitatory AT1 receptors appear to be activated during stress, surgery and anesthesia.

Angiotensin II↗

[Controlled pathological study and preoperative MRI evaluation of the consistency of pituitary adenomas].

BACKGROUND & OBJECTIVE: Consistency of pituitary adenoma may influence surgical remote of the tumor. Preoperative evaluation of tumor consistency will be useful in guiding the operative approach. This study was designed to investigate the relationship among pituitary adenoma consistency, collagen type I and MRI signal intensity. METHODS: Twenty pituitary adenoma patients received transsphenoidal surgery. Preoperative MRI, H-E stains and collagen type I immunohistochemistry(IHC)-autonomic image analysis for tumor specimens were performed RESULTS: Ten tumors were soft, mean T2WI tumor/while matter signal intensity ratio (TWSIR) is 17.38%; six were moderate, mean T2WI TWSIR was 2.01; and 4 were firm, mean T2WI TWSIR was 1.56. Mean collagen type I positive area ratio(CIPAR) of soft, moderate, and firm tumors was 17.38%, 27.30%, and 40.31%, respectively. Both C1PAR and T2WI TWSIR were significantly different among three types (P < 0.01) C1PAR was negatively correlated to T2WI TWSIR(P < 0.01). CONCLUSION: Collagen type I content relates with the consistency of pituitary adenomas. MRI can predict of pituitary consistency adenoma; and those show hypointensity in T2WI are firm.

Adenoma↗

[Disorders of stomach emptying].

During the course of viral infections, acute delays in gastric emptying are common. Usually, dietary measures suffice, but treatment with dopamine antagonists with their additional antiemetic effect, may be beneficial. The major causes of chronic delayed emptying are diabetes mellitus with autonomic neuropathy, connective tissue diseases such as systemic sclerosis, and gastroparesis following gastric surgery. Diet alone is rarely effective, and prokinetic drugs should be prescribed. The new compound cisapride seems to be particularly effective. Abnormally rapid emptying occurs exclusively following surgical destruction of the gastric outlet and may lead to the dumping syndrome. In general this can be adequately controlled by dietary measures.

Diagnosis, Differential↗

[Regional technics for postoperative analgesia].

Postoperative analgesia has been neglected for a long time, whereas postoperative pain has been considered inevitable cost of operations. Postoperative pain causes not only subjective difficulties, but as a stress factor affects functions of the autonomous and endocrine system, which may cause a number of disorders after the surgery. Advances in anesthesiology have contributed to increased role of anesthesiologists in application of regional techniques for postoperative pain. This paper describes regional techniques for postoperative analgesia: epidural, spinal analgesia, intercostal, paravertebral, interpleural, plexus blockade, peripheral nerve blockade and infiltrative local analgesia. Advantages and disadvantages of these techniques in regard to traditional method of parenteral analgesia in the postoperative period have been pointed out. Application of regional analgesia is recommended before the surgery, because it prolongs the time when analgesia is needed for the first time and decreases both pain and postoperative analgesia.

Analgesia↗

[Two cases of adult tethered cord syndrome with surgical treatment].

We report two cases of adult tethered cord syndrome alleviated by untethering surgery. Case 1 was a 35 year-old female who complained of incontinence while exercising. Radiograph revealed spinal disraphism below the L5 level. In addition, magnetic resonance imaging (MRI) showed low placed conus medullaris at the levels of S2 and sacral intradural lipoma. Further urodynamic studies demonstrated normal sphincteric function and autonomous bladder. Diagnosis resulted in the decision to perform an untethering operation. The patient had increased bladder compliance after surgery for untethering and has continued to be continent 16 months post-operatively. Case 2 was a 27-year old female who complained of apprehension to void and straining during urination. Radiograph demonstrated spinal disraphism below the S2 level and MRI revealed low placed conus medullaris at the level of S5 and sacral intradural lipoma. Urodynamic examination verified normal sphincteric function and autonomous bladder. After complete diagnosis, an untethering operation was performed. Post-operatively, bladder compliance and urinary sensation normalized. Furthermore, the patient spontaneously delivered a baby 3 years after having the untethering operation.

Adult↗

Occult respiratory and autonomic dysfunction in craniovertebral anomalies and upper cervical spinal disease.

Sudden unexplained death may be seen with treatment of craniovertebral anomalies and surgery of the upper cervical spine. Death is due to sleep-induced apnea, premonitored by periods of confusion, lethargy, and asthenia. There may be associated hypotension, bradycardia, hyponatremia, hypothermia, inappropriate antidiuretic hormone secretion, and difficulty in micturition. The potential for respiratory failure may be predicted if a CO2 response test demonstrates an attenuated or abnormal response. Apnea during sleep may be reversed by arousal or may require ventilatory support for a period of time. The condition is self-limiting, but remains the major life-threatening complication. Both apnea and autonomic dysfunction are treatable and curable with appropriate diagnosis and management.

Asthenia↗