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At least 379 records · Page 21Linked to original sources

Complications in spondylolisthesis surgery.

STUDY DESIGN: Selected references are cited to illustrate the current status of approaches to surgical complications in isthmic spondylolisthesis surgery. OBJECTIVE: To minimize untoward events and outcomes in the surgical treatment of spondylolisthesis, an awareness of complications and pitfalls specific to spondylolisthesis surgery is necessary. SUMMARY OF BACKGROUND DATA: Pseudarthrosis is the most common complication, and factors that contribute are vertebral geometry, bone grafting options and technique, and immobilization with instrumentation constructs or an orthosis. There has been an increase in neurologic deficits associated with spondylolisthesis surgery during the period of 1996 to 2002. Neurologic sequelae can include cauda equina syndrome, root lesions, autonomic dysfunction, and chronic pain. These can result from reduction maneuvers, instrumentation, and after surgery, although neurologic deficit can occur without identifiable causes. Restoring or maintaining the physiologic sagittal contour of the lumbar spine is a necessary component of surgical planning. METHODS: Literature review. RESULTS: Problems and complications associated with the surgical treatment of spondylolisthesis are well documented in the medical literature. CONCLUSIONS: The occurrence of pseudarthrosis, neurologic deficits, and transition syndromes such as spondylolisthesis acquisita, S1-S2 deformity, and adjacent segment syndrome can be minimized with proper planning and attention to surgical technique.

Humans↗

Treatment of hyperfunctioning thyroid nodules by percutaneous ethanol injection.

BACKGROUND: Autonomous thyroid nodules can be treated by a variety of methods. We assessed the efficacy of percutaneous ethanol injection in treating autonomous thyroid nodules. METHODS: 35 patients diagnosed by technetium-99 scanning with hyperfunctioning nodules and suppressed sensitive TSH (sTSH) were given sterile ethanol injections under ultrasound guidance. 29 patients had clinical and biochemical hyperthyroidism. The other 6 had sub-clinical hyperthyroidism with suppressed sTSH levels (<0.24 &mgr;IU/ml) and normal thyroid hormone levels. Ethanol injections were performed once every 1-4 weeks. Ethanol injections were stopped when serum T3, T4 and sTSH levels had returned to normal, or else injections could no longer be performed because significant side effects. Patients were followed up at 3, 6 and, in 15 patients, 24 months after the last injection. RESULTS: Average pre-treatment nodule volume [18.2 PlusMinus; 12.7 ml] decreased to 5.7 PlusMinus; 4.6 ml at 6 months follow-up [P < 0.001]. All patients had normal thyroid hormone levels at 3 and 6 months follow-up [P < 0.001 relative to baseline]. sTSH levels increased from 0.09 PlusMinus; 0.02 &mgr;IU/ml to 0.65 PlusMinus; 0.8 &mgr;IU/ml at the end of therapy [P < 0.05]. Only 3 patients had persistent sTSH suppression at 6 months post-therapy. T4 and sTSH did not change significantly between 6 months and 2 years [P > 0.05]. Ethanol injections were well tolerated by the patients, with only 2 cases of transient dysphonia. CONCLUSION: Our findings indicate that ethanol injection is an alternative to surgery or radioactive iodine in the treatment of autonomous thyroid nodules.

Journal Article↗

Anaesthesia for chronic spinal cord lesions.

Increasing numbers of patients with spinal cord injury present for surgery or obstetric care. Spinal cord injury causes unique pathophysiological changes. The most important peri-operative dangers are autonomic dysreflexia, bradycardia, hypotension, respiratory inadequacy and muscle spasms. Autonomic dysreflexia is suggested by headache, sweating, bradycardia and severe hypertension and may be precipitated by surgery, especially bladder distension. Patients with low, complete lesions, undergoing surgery below the level of injury, may safely do so without anaesthesia provided there is no history of autonomic dysreflexia or troublesome spasms. An anaesthetist should be present to monitor the patient in this situation. General anaesthesia of sufficient depth is effective at controlling spasms and autonomic dysreflexia but hypotension and respiratory dysfunction are risks. There is a growing consensus that spinal anaesthesia is safe, effective and technically simple to perform in this group of patients. We present a survey of 515 consecutive anaesthetics in cord-injured patients and a review of the current literature on anaesthesia for patients with chronic spinal cord lesions.

Analgesia, Obstetrical↗

Trigeminocardiac reflex during surgery in the cerebellopontine angle.

OBJECT: In different experimental studies authors have analyzed the autonomic responses elicited by the electrical, mechanical, or chemical stimulation of the trigeminal nerve system. The trigeminocardiac reflex (TCR) is a well-recognized phenomenon that consists of bradycardia, arterial hypotension, apnea, and gastric hypermotility. It occurs during ocular surgery and during other manipulations in and around the orbit. Thus far, it has not been shown that central stimulation of the trigeminal nerve can also cause this reflex. METHODS: The TCR was defined as clinical hypotension with a drop in mean arterial blood pressure (MABP) of more than 20% and bradycardia lower than 60 beats/minute. Pre-, intra-, and postoperative heart rate (HR) and MABP were reviewed retrospectively in 125 patients who underwent surgery for tumors of the cerebellopontine angle (CPA), and they were divided into two groups on the basis of the occurrence of the TCR during surgery. Of the 125 patients, 14 (11%) showed evidence of the TCR during dissection of the tumor near the trigeminal nerve at the brainstem. Their HRs fell 38% and their MABPs fell 48% during operative procedures as compared with preoperative levels. After cessation of manipulation, the HRs and the MABPs returned to preoperative levels. Risk factors for the occurrence of the TCR were compared with results from the literature. CONCLUSIONS: The authors' results show the possibility of occurrence of a TCR during manipulation of the central part of the trigeminal nerve when performing surgery in the CPA.

Adolescent↗

Essential role of gamma interferon in survival of colon ascendens stent peritonitis, a novel murine model of abdominal sepsis.

Despite considerable progress, peritonitis and sepsis remain life-threatening conditions. To improve the understanding of the pathophysiology encountered in sepsis, a new standardized and highly reproducible murine model of abdominal sepsis termed colon ascendens stent peritonitis (CASP) was developed. In CASP, a stent is inserted into the ascending colon, which generates a septic focus. CASP employing a stent of 14-gauge diameter (14G stent) results in a mortality of 100% within 18 to 48 h after surgery. By inserting stents of small diameters, mortality can be exactly controlled. Thus, CASP surgery with insertion of a 22G or 18G stent (22G or 18G CASP surgery) results in 38 or 68% mortality, respectively. 14G CASP surgery leads to a rapid invasion of bacteria into the peritoneum and the blood. As a consequence, endotoxemia occurs, inflammatory cells are recruited, and a systemic inflammatory response syndrome develops. Interestingly, the most pronounced upregulation of inflammatory cytokines (gamma interferon [IFN-gamma], tumor necrosis factor alpha [TNF-alpha] and interleukin-12) is observed in spleen and lungs. CASP surgery followed by stent removal at specific time intervals revealed that all animals survived if intervention was performed after 3 h, whereas removal of the septic focus after 9 h did not prevent death, suggesting induction of autonomous mechanisms of a lethal inflammatory response syndrome. 18G CASP surgery in IFN-gamma receptor-deficient (IFNgammaR-/-) mice revealed an essential role of IFN-gamma in survival of sepsis, whereas TNF receptor p55-deficient (TNFRp55-/-) mice did not show altered survival rates. In summary, this study describes a novel animal model that closely mimics human sepsis and appears to be highly suitable for the study of the pathophysiology of abdominal sepsis. Importantly, this model demonstrates a protective role of IFN-gamma in survival of bacterial sepsis.

Abdomen↗

Coronary artery bypass surgery in heart failure patients with chronic reversible and irreversible myocardial dysfunction: effect on heart rate variability.

It is unknown whether surgical revascularization of viable and chronic reversibly dysfunctional myocardium in patients with heart failure is associated with a favorable effect on the autonomic control of heart rate. We studied 38 coronary artery bypass surgery (CABG) patients with an ejection fraction of 36 +/- 7%. Before CABG, the patients underwent 48-hour ambulatory electrocardiographic monitoring to measure heart rate variability (HRV), echocardiography to assess left ventricular function, and positron emission tomography and low-dose dobutamine echocardiography to assess viability. Six months after CABG, ambulatory electrocardiographic monitoring and echocardiography were repeated to assess HRV and recovery of left ventricular function. In spite of viable myocardium and recovery of left ventricular function following CABG, HRV indices were reduced 6 months postoperatively. A potential prognostic benefit gained by revascularizing patients with viability may occur in spite of deteriorated autonomic control of heart rate.

Aged↗

Gaze-contingent soft tissue deformation tracking for minimally invasive robotic surgery.

The introduction of surgical robots in Minimally Invasive Surgery (MIS) has allowed enhanced manual dexterity through the use of microprocessor controlled mechanical wrists. Although fully autonomous robots are attractive, both ethical and legal barriers can prohibit their practical use in surgery. The purpose of this paper is to demonstrate that it is possible to use real-time binocular eye tracking for empowering robots with human vision by using knowledge acquired in situ. By utilizing the close relationship between the horizontal disparity and the depth perception varying with the viewing distance, it is possible to use ocular vergence for recovering 3D motion and deformation of the soft tissue during MIS procedures. Both phantom and in vivo experiments were carried out to assess the potential frequency limit of the system and its intrinsic depth recovery accuracy. The potential applications of the technique include motion stabilization and intra-operative planning in the presence of large tissue deformation.

Artificial Intelligence↗

[Atrial fibrillation after coronary artery bypass surgery. The significance of preoperative vagus modulation and ectopic atrial activity].

To investigate the impact of pre-operative autonomic balance and atrial ectopic activity on the risk of atrial fibrillation or flutter after aorto-coronary artery bypass surgery 24-hour Holter monitoring was analyzed in 102 patients before coronary artery bypass grafting. Index for vagal tone was calculated as % successive RR-interval differences > 6%. Twenty-nine (28%) of the 102 patients developed atrial fibrillation or flutter. Independent predictors (90% confidence interval) of postoperative atrial fibrillation or flutter were identified by logistic regression analysis: the independent predictors were older age, relative risk 1.07/year (1.02-1.12), vagal index < 10%, relative risk 4.50 (1.40-14.5), > or= 10 ectopic supraventricular beats/24 hour, relative risk 3.03 (1.05-8.72), and one or more event of non-sustained supraventricular tachycardia, relative risk 3.02 (1.11-8.22). Thus, age of the patient, attenuated preoperative cardiac vagal modulation, ectopic supraventricular beats, and paroxysmal non-sustained supraventricular tachycardia are independent risk factors for the development of atrial fibrillation or flutter after coronary artery bypass surgery.

Atrial Fibrillation↗

Treatment of gustatory sweating with botulinum toxin.

Gustatory sweating is an autonomic disorder that frequently occurs after parotid gland surgery. We investigated the action of intracutaneous injections of botulinum toxin (BTX) (1.0-2.0 mouse units/2.25-cm2 skin area) in 45 patients (mean age, 52 years) with gustatory sweating. The area of hyperhidrosis was determined by Minor's iodine test before and up to 24 weeks after the injection. The effect of BTX was assessed by measuring the hyperhidrotic area. The maximum BTX-induced reduction of gustatory sweating was seen at 7.4 +/- 4.5 days after injection. The area of sweating decreased from 17.6 +/- 8.6 cm2 before BTX to 1.3 +/- 1.6 cm2 after BTX (p < 0.0001). Half the patients rated gustatory sweating subjectively as completely abolished, and the remainder felt pronounced improvement. No toxic effects were observed. In none of the patients did hyperhidrosis recur over a 6-month follow-up. We conclude that BTX is a safe and effective treatment that can be recommended as the therapy of choice in gustatory sweating.

Adult↗

A modern rationale for the use of phenoxybenzamine in urinary tract disorders and other conditions.

BACKGROUND: Phenoxybenzamine (PBZ) is a nonselective, irreversible alpha-adrenergic receptor antagonist that is approved for the treatment of diaphoresis and hypertension associated with pheochromocytoma. It may also be useful in several chronic conditions whose pathogenesis is mediated or affected by alpha-adrenergic stimulation, such as lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH) and neurogenic bladder (eg, secondary to myelomeningocele and in sphincter dyssynergia and autonomic dysreflexia); in an adjunctive role after urogenital surgery or brachytherapy by relieving symptoms associated with increased alpha-adrenergic tone; and in the treatment of complex regional pain syndrome (CRPS) and prostatitis. However, carcinogenic concerns may have limited its potential application. OBJECTIVE: The purpose of this article is to reassess the usefulness and contemporary application of PBZ for the control of urinary tract symptoms associated with BPH and neurogenic bladder, after urogenital surgery and brachytherapy, and in certain other conditions (eg, CRPS, prostatitis). METHODS: A search of literature published from 1966 to 2002 was performed on MEDLINE using the search terms phenoxybenzamine, alpha-adrenergic blockers, benign prostatic hyperplasia, neurogenic bladder, urinary retention, and complex regional pain RESULTS: Despite concerns about possible carcinogenicity, no reports of drug-related tumors have been made since PBZ's introduction in 1953. Investigators have used PBZ in off-label trials to alleviate symptoms of a variety of conditions that cause urinary retention. In adult male patients with retention due to inguinal hernioplasty and female patients with retention caused by vaginal repair, as well as in pediatric patients with myelomeningocele, treatment with PBZ improved bladder function and, in the patients with myelomeningocele, was associated with reduced incidence of urinary tract infection. Larger tri- als of PBZ in men with BPH produced significant urinary symptom relief (P < 0.05 in 2 studies). Moreover, studies suggest that PBZ may be useful in alleviating pain due to trauma and CRPS. The most common adverse events appear to be dizziness, impotence and ejaculatory dysfunction, and nasal stuffiness. CONCLUSIONS: No drug-related tumors in humans have been reported after -50 years of clinical experience with PBZ. Clinical trials have demonstrated that it can relieve symptoms in patients with BPH and other urologic and pain-related conditions.

Adrenergic alpha-Antagonists↗

Comparison of the haemodynamic actions of desflurane/N2O and isoflurane/N2O anaesthesia in vascular surgical patients.

BACKGROUND: The purpose of this study was to compare heart rate and arterial blood pressure response to desflurane/N2O vs isoflurane/N2O anaesthesia in a randomized clinical trial performed in patients before vascular surgery. METHODS: To evaluate associated changes in the autonomic nervous system with maintenance of anaesthesia, we used power spectral analysis (PSA) of heart rate and blood pressure and measured plasma catecholamine concentrations. Twenty-five patients whose trachea had been intubated after propofol induction were given either desflurane or isoflurane at 1 and 1.5 MAC in N2O (60%) in a random manner. RESULTS: At an anaesthetic depth of up to 1.5 MAC, arterial blood pressure, indices of sympathetic activity derived from PSA, decreased with both anaesthetics, while heart rate and plasma catecholamine concentrations did not significantly change. Plasma renin activity significantly increased at 1.5 MAC anaesthesia in both groups. CONCLUSIONS: We conclude that sympathetic hyperactivity previously reported during desflurane anaesthesia in healthy volunteers is not frequent in clinical practice in elderly vascular surgical patients under desflurane/N2O anaesthesia, since it occurs at an anaesthetic depth which cannot be reached in these patients because of the lowering arterial blood pressure effects of desflurane, which are similar to those of isoflurane.

Adult↗

High prevalence of occult papillary thyroid carcinoma in a surgical series for benign thyroid disease.

In a surgical series of 277 consecutive patients operated on the thyroid for benign diseases, a high prevalence rate (10.5%) of occult papillary carcinoma was found by means of an accurate histologic examination. Indications for surgery were euthyroid multinodular goiter in 25 patients, autonomously hyperfunctioning adenoma in 2 and Graves' disease in 2 patients. Neoplastic foci were unilaterally found in 25 cases but multifocally in 6 and bilaterally in 4 cases: the diameters ranged from 2-10 mm. After operation (14 subtotal and 15 total thyroidectomies), all patients received TSH-suppressive doses of T4. At a mean follow-up of 5.6 years, neither local recurrences nor lymph node or distant metastases had occurred; no patient died of the tumor. In keeping with other surgical and autopsy series, the prevalence of occult thyroid carcinoma in a normal population is calculated to be about 5-10%, whereas it is known that the prevalence of clinically evident thyroid cancer is only 0.05%. This means that only 1-2% of occult carcinomas may evolve in an overt tumor during life. In view of such an epidemiologic difference and the favorable course of our patients, although the mean follow-up is rather short, we suggest that lobectomy plus T4 treatment may be considered an adequate therapeutic approach in patients with occult papillary thyroid carcinoma.

Adolescent↗

[Perioperative blood glucose levels in children].

The perioperative blood glucose (BG) level may represent autonomic responses to various stresses by anesthesia and surgery. We studied the effects of regional blocks combined with general anesthesia on the BG response in pediatric patients. We could not find any significant differences in BG levels between blocked and non-blocked patients. However, BG levels of the children who had been hysterical or crying during the induction of anesthesia were significantly higher than those of the children who had been calm or sleeping. Forty healthy children, aged 1-3 yrs who were scheduled for elective urological surgery were studied. Anesthesia was induced with halothane in oxygen. The anesthesiologist recorded the children's attitude before and during the induction of anesthesia, and described as "calm or asleep (Calm-group), and hysterical or crying (Crying-group)". Patients were assigned randomly to two groups as follow; Group A (n = 20): receiving nerve blocks, Group B (n = 20): without the blocks. The anesthesia was maintained with 1-2.5% halothane in oxygen required to maintain the hemodynamic parameters within 10% of baseline value before surgery. Both groups received lactated-Ringer's solution during the study period. The venous BG levels were determined 5 times, i.e. immediately after asleep, 5, 15, 30 minutes after skin incision and at the conclusion of surgery. BG levels were compared between groups using Mann-Whitney Test. There was no significant difference in BG levels between Group A and B throughout the study period. But BG values of Crying-group (n = 9) were significantly higher than those of Calm-group (n = 31) during perioperative period.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Inhalation↗

[Surgical preparation in hyperthyroidism and therapy of thyrotoxic crisis].

Any type of hyperthyroidism with an indication for surgical treatment requires adequate medical preparation. A major reason for this postulate is avoidance of hyperthyroid crisis. Medical control of severe hyperthyoidism is best achieved by antithyroid drugs, mild cases of thyroid autonomy maybe sufficiently pretreated by beta-adrenergic blockers. Hyperthyroid crisis due to iodine contamination of a goiter with a considerable mass of autonomously functioning tissue may require acute and early surgery if medical control fails or does not show improvement within a few days.

Humans↗