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At least 181 records · Page 10Linked to original sources
PubMed1994

A case of localised ureteric amyloidosis.

We describe a case of localised amyloidosis of the distal ureter in a 66-year-old lady who presented with intermittent haematuria. Ureteric transitional cell carcinoma was strongly suspected from the clinical and radiological features, and subsequent nephroureterectomy was performed. Histology revealed nodular eosinophilic deposits in the ureteric wall, with the staining characteristics of amyloid. The literature is reviewed, and conservative surgery is advocated, based on a greater awareness together with improved intraoperative diagnosis of this rare lesion.

Aged↗
PubMed2006

Challenging the advanced: cardiac surgery without awareness of a pheochromocytoma.

We report the case of a 75-year-old male patient who underwent bypass surgery. Intraoperatively unstable hemodynamics with excessive arterial blood pressure was observed. This resulted in the tearing of an anastomosis, which subsequently required hemostasis for repeated bleeding. Postoperatively, laboratory findings and diagnostic imaging confirmed the diagnosis made intraoperatively of a pheochromocytoma. Any surgery without awareness of the possibility of a pheochromocytoma will dramatically increase intraoperative and postoperative morbidity and mortality, especially in cardiac surgery. The uncontrolled release of catecholamines raises arterial blood pressure which can become life-threatening and lead to serious intraoperative complications, as well as cerebrovascular and cardiac comorbidity.

Aged↗
PubMed2000

Accuracy of gamma probes in localizing radioactivity: in-vitro assessment and clinical implications.

BACKGROUND: Radioguided surgery (RGS) uses gamma probes to localize radioactive targets. We examined the in-vitro localizing properties of commercially available gamma probes for three common RGS radioisotopes: technetium-99m (99mTc), indium-111 (111In), and iodine-125 (125I). METHODS: The linear and angular localizing properties of five gamma probes were assessed. Radioactive counts in air were obtained at multiple energy threshold settings for each radioisotope. The full width half maximum (FWHM) and angular half maximum (AHM) were calculated to determine localizing accuracy. RESULTS: The FWHM of the five probes ranged from 1.2 to 3.4 cm for 99mTc, 1.8 to 2.7 cm for 111In and 1.6 to 2.8 cm for 125I. AHM of the probes ranged from 20 to 49 degrees for 99mTc, 14 to 35 degrees for 111In, and 18 to 47 degrees for 125I. The ranking of probe accuracy depended on the radioisotope studied. Absolute count rates varied with energy threshold settings for each probe and radioisotope. Probes required individualized energy threshold settings for optimal performance. CONCLUSIONS: The five probes varied in their characteristics for localizing the three radioisotopes. Each probe has particular detection characteristics that may change with different radioisotopes. Differences in radioisotope detection may explain intraoperative variation in localization during lymphatic mapping and sentinel lymph node dissection (LM/SL). Surgeons should be aware of probe performance characteristics before intraoperative use.

Gamma Rays↗
PubMedDate not supplied

Intravascular lymphomatosis of the brain. Report of a case using an intraoperative cytologic preparation.

BACKGROUND: Intravascular lymphomatosis (IVL) of the brain is a rare non-Hodgkin's lymphoma characterized by proliferation of tumor cells in the lumina of blood vessels. Although an intraoperative cytologic examination of the brain is routinely done, the cytologic features of IVL are rarely encountered by pathologists. We report a case of IVL diagnosed by an intraoperative cytology preparation. CASE: A 62-year-old woman presented with a seizure and fever. Computed tomography and magnetic resonance imaging of the brain were insufficient to establish a diagnosis but suggested a cerebral infarction, so a stereotactic brain biopsy was performed. On an intraoperative cytologic examination, a few small and medium-sized vessels were filled with tumor cells showing atypical, pleomorphic, large nuclei. Immunohistochemical staining using paraffin-embedded tissue revealed intraluminal tumor cells expressing leukocyte common antigen and CD20 but not CD3. CONCLUSION: This disease must be considered one of the diagnostic possibilities in any patient with rapidly progressive dementia and cerebral infarction. Increased awareness of this disease and intraoperative early diagnosis are important for its successful management.

Antigens, CD20↗
PubMed1991

Intraoperative cardiovascular collapse secondary to latex allergy.

An apparent allergic reaction has been noted in children undergoing open urological surgery. This condition is characterized by precipitous hypotension, tachycardia and upper body flushing, and it often causes termination of the procedure. Latex allergy has been identified as the possible inciting event. Contact of latex rubber gloves with intra-abdominal structures (handling bowel) appears to be the most dramatic trigger mechanism for this reaction. We report on 10 patients with latex allergy, 6 of whom have myelomeningocele, who have undergone reconstructive surgery. Severe anaphylactic shock developed intraoperatively in 5 patients and during a barium enema performed with a latex catheter in 1 patient. These 6 patients had previous allergic reactions to latex material, which was not detected preoperatively. In the remaining 4 patients latex allergy was diagnosed preoperatively. A total of 6 patients agreed to a skin prick test to liquid latex. Three patients reacted with a wheal size greater than or equal to a histamine control at a dilution of 1:1,000 and 3 patients at 1:100. In contrast, none of the 5 normal controls reacted to any of the concentrations including full strength latex. A history of exposure to latex products (balloons, surgical gloves, catheters, condoms and so forth) with allergic reactions should heighten surgeon awareness of a potentially severe intraoperative reaction. Furthermore, a skin prick test may be used to screen high risk patients such as those with myelomeningocele. A protocol involving preoperative corticosteroid and antihistamine therapy is recommended.

Adolescent↗
PubMed2005

Cerebral monitoring in the operating room and the intensive care unit - an introductory for the clinician and a guide for the novice wanting to open a window to the brain. Part II: Sensory-evoked potentials (SSEP, AEP, VEP).

An evoked potential differs from the EEG mainly in two ways: 1. The EEG is a random, continuous signal, which arises from the ongoing activity of the outer layers of the cortex. An evoked potential is the brain's response to a repetitive stimulus along a specific nerve pathway. 2.EEG signals range from 10-200 milliVolt (mV). Evoked potentials are smaller in amplitude (1-5-20 microVolt requiring precise electrode positioning and special techniques (signal averaging) to extract the specific response from the underlying EEG "noise". The technique of signal averaging, as originally described by Dawson in 1954 [69J, has been further developed in computer processing. The technique is now used by applying a stimulus repeatedly--preferably at randomized intervals--and to record the evoked response over the corresponding area of the brain, averaging out mathematically the change over the number of stimuli. Rationale for the use of EPs in the OR and the ICU. Evoked potentials (EPs) serve the following major purposes: 1. Monitoring of the functional integrity of neural structures that may be at risk during, for instance, ECC (extracorporeal circulation) or endarterectomy indicating cerebral hypoxia. 2. Monitoring of the effects of anesthetic agents and other centrally active drugs, which, besides the cortex, affect deeper neuronal structures. 3. Orthopedic cases where the spinal cord is at risk such as Harrington rod insertion and removal. 4. Clamping of the abdominal aortic artery during aneurysmectomy resulting in a potential damage of the lower parts of the spinal cord. 5. Clipping of an intracerebral aneurysm, which may be impeding blood flow to vital cerebral textures. 6. An indicator of cerebral hypoxia when the blood pressure is deliberately lowered. 7. Operation on peripheral nerves and nerve roots to identify early trauma. 8. Monitoring the cerebral function during controlled hypothermia when the EEG becomes flat. 9. Monitoring of the pathophysiological conditions after severe head trauma and the effects of therapy. 10. An intraoperative warning device of unsuspected awareness during light anesthesia when movement is abolished by muscle relaxants and cardiovascular responses are modified by vasoactive drugs. In case of the latter the stimulus is a small electrical potential applied to the skin of the hand. Thereafter, the stimulus travels along the specific nervous pathways inducing (= generating) potential activation at various sites. The generation of potential changes at various sites along the pathway is an index for the integrity of the nerve. Thus, the evoked potential can be considered a neurophysiological response (usually of the cortex) to impulses originating from some externally stimulated sensory nerve. They provide a physiological measure of the functional integrity of the sensory nerve pathway, which can be used as a clinical diagnostic tool as well as for intraoperative monitoring. The evoked potential usually is recorded from the specific cortical area corresponding to the stimulus input. The classification of evoked potentials. Stimulating a sensory nervous pathway induces evoked potentials. If the auditory nerve is stimulated by "clicks" from headphones, it is called the auditory evoked potential (AEP). The early part of the AEP waveform (less than 10 msec) is called the Brainstem Auditory Evoked Potential (BAEP) since it reflects the passing of the impulse through the brainstem. If a nerve on the arm or the leg is stimulated by a small electrical current applied to the overlying skin, it is called the Somatosensory Evoked Potential (SSEP). If, however, the retina is stimulated by means of flicker light or a sudden change in a checkerboard pattern, the evoked potential thus recorded over the corresponding cortical area is called the Visual Evoked Potential (VEP). Evoked potentials are used both as a diagnostic tool and as a monitoring technique. As diagnostic tests, evoked potentials are useful to evaluate neurologic disorders such as: a) multiple sclerosis, b) acoustic nerve tumors, and c) optic neuritis. As a monitoring modality, evoked potentials are used during all surgical procedures, which might compromise part of the brain or the spinal cord.

Brain↗
PubMed1995

Safety issues regarding early extubation after coronary artery bypass surgery.

Potential safety issues related to early extubation include the effect of changes in anesthetic management on intraoperative hemodynamics, stress responses and awareness, altered management in the control of pain, shivering and ischemia in the early postoperative period, and the risks of reintubation in patients who might require reoperation for bleeding. The literature does not implicate any technique necessary to facilitate early extubation as being associated with adverse outcome. Definitive outcome studies are only beginning to be presented, but the data so far suggest that early extubation is not associated with any increase risk of mortality or morbidity, including, specifically, myocardial ischemia or infarction. These studies of early extubation have involved selected patients, and it is unknown but unlikely that early extubation can be recommended for all patients, particularly those who might be at risk for perioperative ischemia as the result of inadequate myocardial protection, unsatisfactory surgery, or other factors yet to be identified. In the absence of definitive studies, it may be prudent to manage high-risk patients with a more conservative approach. Complications such as low cardiac output, arrhythmias, stroke, and perioperative myocardial infarction have not increased with early extubation, at least in patients selected for early extubation on the basis of preoperative characteristics. In summary, available evidence suggests that early extubation, applied to many but probably not all patients, can be accomplished without demonstrable patient harm. A coordinated approach involving anesthesia, surgery, nursing, respiratory therapy, and other support services is essential, and constant reevaluation as events unfold, rather than rigid protocols, allows care to be individualized to the specific needs of each patient.

Anesthesia, General↗
PubMed1991

Atrial fibrillation during a subarachnoid block in a patient with undiagnosed mitral valve prolapse.

Mitral valve prolapse (MVP) is a common cardiac abnormality, and there are numerous documented cases of intraoperative dysrhythmias. However, the authors describe what is believed to be the first case of atrial fibrillation in a patient with an undiagnosed MVP who was given a subarachnoid block. A possible clinical sequencing for the subarachnoid block is offered. The differential diagnosis, etiology, pathology, and pathophysiology of MVP are discussed. Also detailed are the management of intraoperative dysrhythmias. Physicians should be aware, as in the case reported, that a new-onset atrial fibrillation can occur, even without previously diagnosed MVP.

Aged↗
PubMed1988

Complications of retroperitoneal lymph node dissection.

In summary, the complications of retroperitoneal lymph node dissection for low-stage testis cancer appear to be minimal, especially with the advent of nerve sparing techniques. However, the approximate 30 per cent of patients who require primary chemotherapy and do not attain a complete remission are candiates for postchemotherapy retroperitoneal lymphadenectomy, and these patients are subject to a higher risk of intraoperative and postoperative complications. Maintaining awareness of these potential complications may aid in preventing morbidity in this group of patients.

Humans↗
PubMed1996

Therapeutic suggestion has not effect on postoperative morphine requirements.

This study was designed to confirm the effect of therapeutic intraoperative auditory suggestion on recovery from anesthesia, to establish the effect of preoperative suggestion, and to assess implicit memory for intraoperative information using an indirect memory task. Sixty consenting unpremedicated patients scheduled for elective gynecologic surgery were randomly divided into three equal groups: Group 1 received a tape of therapeutic suggestions preoperatively, and the story of Robinson Crusoe intraoperatively; Group 2 heard the story of Peter Pan preoperatively and therapeutic suggestions intraoperatively; Group 3 heard the Crusoe story preoperatively and the Peter Pan story intraoperatively. A standardized anesthetic technique was used with fentanyl, propofol, isoflurane, and nitrous oxide. After surgery, all patients received patient-controlled analgesia (PCA) with a standardized regimen. In the 24 h postsurgery, morphine use was recorded every 6 h and at 24 h an indirect memory test (free association) was used to test for memory of the stories. Anxiety scores were measured before surgery and at 6 and 24 h postsurgery. There were no significant differences between groups for postoperative morphine use, pain or nausea scores, anxiety scores, or days spent in hospital after surgery. Seven of 20 patients who heard the Pan story intraoperative gave a positive association with the word "Hook," whereas 2 of 20 who did not hear the story gave such an association. Indirect memory for the Pan story was established using confidence interval (CI) analysis. (The 95% CI for difference in proportion did not include zero). No indirect memory for the Crusoe story could be demonstrated. This study did not confirm previous work which suggested that positive therapeutic auditory suggestions, played intraoperatively, reduced PCA morphine requirements. In contrast, a positive implicit memory effect was found for a story presented intraoperatively.

Adult↗
PubMed2002

Bispectral index in assessment of adequacy of general anaesthesia for lower segment caesarean section.

Awareness among parturients during general anaesthesia for caesarean section, though now uncommon, remains a concern for obstetric anaesthetists. We examined the adequacy of our general anaesthetic technique for avoiding explicit awareness by determining the depth of anaesthesia using Bispectral Index (BIS) monitoring. Twenty ASA1 parturients having general anaesthesia for lower segment caesarean section were studied. The drugs and doses used for each anaesthetic were similar Intraoperative Bispectral Index, haemodynamic parameters, end-tidal isoflurane concentration and inspired nitrous oxide fraction were measured and the postoperative incidence of explicit awareness was assessed. All anaesthetists were blinded to the Bispectral Index value throughout the operation. The depth of anaesthesia at various stages of the operation was evaluated by recording the Bispectral Index. Patients were interviewed for any intraoperative recall or awareness at the end of operation. A median BIS of 70 or below was recorded on most occasions during surgery. The range was 52 to 70, with values reaching 60 and below at intubation, uterine incision and delivery. Haemodynamic stability was satisfactory and there was no case of uterine atony, fetal compromise or postpartum haemorrhage. No patient experienced intraoperative dreams, recall or awareness. Our current general anaesthetic technique appeared inadequate to reliably produce BIS values of less than 60 that are associated with a low risk of awareness. However, no patients experienced explicit awareness.

Adult↗
PubMed2004

Unconscious auditory priming during surgery with propofol and nitrous oxide anaesthesia: a replication.

BACKGROUND: Priming during anaesthesia has been hard to replicate and the conditions under which it occurs remain poorly understood. We replicated and extended a recent study to determine whether intraoperative priming during propofol and nitrous oxide anaesthesia is a reliable phenomenon, whether it occurs due to awareness during word presentation and whether it is suppressed by a dose of fentanyl at induction. METHODS: Words were played through headphones during surgery to 62 patients receiving propofol and nitrous oxide anaesthesia. Thirty-two patients received fentanyl 1.5 microg kg(-1) at induction and 30 received no fentanyl. Neuromuscular blocking drugs were not used. Depth of anaesthesia was measured using the bispectral index (BIS). Anaesthetic variables were recorded at 1 min intervals during word presentation. On recovery, implicit and explicit memory were assessed using an auditory word-stem completion test and a yes-no word-recognition test, respectively. RESULTS: BIS, blood pressure, end-tidal carbon dioxide and heart rate during word presentation did not differ between the study groups. The infusion rate of propofol and the patients' ventilatory frequency were significantly higher in the group not receiving fentanyl. No patient had unprompted explicit recall of surgery, although there was above-zero performance in six patients on the yes-no recognition task (P<0.05). There was no physiological evidence of awareness during anaesthesia (median mean-BIS=38 in the no-fentanyl group and 42 in the fentanyl group). There was evidence for priming (mean priming score=0.09, P<0.05 in the no-fentanyl study group; mean priming score=0.07, P<0.05 in the fentanyl group) even when patients with momentary light anaesthesia (maximum recorded BIS> or =60) and/or positive recognition scores were excluded from the analysis. CONCLUSIONS: Existing knowledge can be primed by information presented during propofol and nitrous oxide anaesthesia. This priming is evidence of unconscious information processing and not the result of moments of awareness.

Acoustic Stimulation↗
PubMed1983

Diverticulitis of the cecum.

Ten patients with diverticulitis of the cecum are reported upon herein. The disease is difficult to distinguish preoperatively from that of appendicitis and may be difficult to distinguish intraoperatively from carcinoma of the cecum. The diverticula are usually solitary and may be of the true or false variety. A review of the literature is presented, and the difficulties of diagnosis and treatment are discussed. We advocate local resection of the diverticulum, when possible, and a right hemicolectomy when the diagnosis is in doubt or when local resection or invagination would jeopardize the ileocecal valve or the blood supply to the intestine. With more awareness of diverticulitis of the cecum, intraoperative diagnosis may be made easier and the treatment simplified.

Adult↗
PubMed1999

Cauda equina compression due to a laminar hook: A late complication of posterior instrumentation in scoliosis surgery.

Whilst neurologic injury following correction of scoliosis with CD-instrumentation is generally known to be an early complication, any late occurrence of cauda compression secondary to employment of a laminar hook-rod construct is exceptional. We report on such a rare case of late occurrence of cauda equina syndrome, when a laminar hook at level L2 became symptomatic causing compression of the cauda equina almost a decade after spine surgery. This case demonstrates that one should not only be aware of a potential neural injury at intraoperative placement of laminar hooks, but also one is reminded that a laminar hook poses the threat of late neurologic injury years after successful osseous spinal fusion. The surgeon treating patients with scoliosis must be aware of the possible complication described in our patient in addition to those that have already been well documented.

Adult↗
PubMed1988

Localization of pancreatic insulinoma: comparison of pre- and intraoperative US with CT and angiography.

Methods of preoperative radiologic localization of insulinoma were compared in 52 patients, 44 of whom had solitary tumors. Examinations performed in these 44 patients were preoperative ultrasonography (US) in 28, angiography in 26, and computed tomography in 23. Prospective sensitivities were 61%, 54%, and 30%, respectively. Imaging sensitivities were lower for the eight patients with multiple insulinomas. In 28 of the 44 patients, intraoperative US was performed without the examiner being aware of the surgical findings. The sensitivity was 84%. Four insulinomas were not palpable but were visualized sonographically. The combined sensitivity of intraoperative US and surgical palpation for detecting solitary insulinomas was 100%. High-frequency intraoperative US is valuable for detecting occult solitary insulinomas and considerably useful for determining the proximity of insulinomas to the pancreatic and bile ducts.

Adenoma, Islet Cell↗