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Robertson CS, Chung SC, Bouchier-Hayes D, Cockram CS, Li AK. Laparoscopic left adrenalectomy: a new approach. THE AUSTRALIAN AND NEW ZEALAND JOURNAL OF SURGERY 1995; 65:619-20. [PMID: 7661812 DOI: 10.1111/j.1445-2197.1995.tb01713.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Left adrenalectomy has been performed previously via anterior, posterior, loin or thoracoabdominal approaches. In the classical transabdominal approach the left adrenal gland is resected following either mobilization of the spleen with the tail of the pancreas or after entering the lesser sac, mobilizing the inferior border of the pancreas off the adrenal gland. This report describes laparoscopic left adrenalectomy, in a patient with Conn's syndrome, performed by a new approach via the root of the left transverse mesocolon.
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Robertson CS, Gopinath SP, Chance B. A new application for near-infrared spectroscopy: detection of delayed intracranial hematomas after head injury. J Neurotrauma 1995; 12:591-600. [PMID: 8683610 DOI: 10.1089/neu.1995.12.591] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Clinical studies have documented the importance of secondary brain insults in determining neurologic outcome after head injury. Delayed intracranial hematomas are one of the most easily remediable causes of secondary injury if identified early, but can cause significant disability or death if not promptly recognized and treated. Early identification and treatment of these lesions that appear or enlarge after the initial CT scan may improve neurological outcome. Serial examinations using near-infrared spectroscopy (NIRS) to detect the development of delayed hematomas were obtained in 167 patients. The difference in absorbance of light (deltaOD) at 760 nm between the normal and the hematoma side was measured serially during the first 3 days after injury. Twenty-seven (16%) of the patients developed some type of late hematoma: an intracerebral hematoma in 8 patients, an extracerebral hematoma in 6 patients, and a postoperative hematoma in 13 patients. Eighteen of the delayed hematomas caused significant mass effect and required surgical evacuation. The hematomas appeared between 2 and 72 h after admission. In 24 of the 27 patients, a significant increase (>0.3) in the deltaOD occurred prior to an increase in intracranial pressure or a change in the neurological examination, or a change on CT scan. Early diagnosis using MRS may allow early treatment and reduce secondary injury caused by delayed hematomas.
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Gurtner GC, Robertson CS, Chung SC, Ling TK, Ip SM, Li AK. Effect of carbon dioxide pneumoperitoneum on bacteraemia and endotoxaemia in an animal model of peritonitis. Br J Surg 1995; 82:844-8. [PMID: 7627528 DOI: 10.1002/bjs.1800820639] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Laparoscopy is increasingly used in conditions complicated by peritonitis. A theoretical concern is that carbon dioxide pneumoperitoneum may increase bacteraemia. This study examines the effect of carbon dioxide pneumoperitoneum on bacteraemia, endotoxaemia and physiological correlates of sepsis in an animal model of peritonitis. New Zealand white rabbits were assigned to three groups of six animals. Group 1 received an intraperitoneal inoculation of 10(9) colony-forming units of Escherichia coli followed by a 10-cm midline laparotomy. Group 2 received an identical bacterial inoculum followed by a 12-mmHg carbon dioxide pneumoperitoneum for 1 h. Group 3 received no bacteria but had a 12-mmHg carbon dioxide pneumoperitoneum for 1 h. Groups 1 and 2 had significantly higher levels of bacteraemia (P < 0.01) and endotoxaemia (P < 0.01) accompanied by significantly lower mean arterial pressures (P < 0.05) and higher heart rates (P < 0.05) compared with group 3. After 6 h groups 1 and 2 were significantly hypocarbic (P < 0.01), leucopenic (P < 0.01) and thrombocytopenic (P < 0.01). There was no difference between group 1 and group 2. A carbon dioxide pneumoperitoneum of 12 mmHg does not increase bacteraemia or endotoxaemia, nor does it adversely affect physiological or laboratory correlates of sepsis compared with laparotomy in this animal model of peritonitis.
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Gopinath SP, Robertson CS, Contant CF, Narayan RK, Grossman RG. Clinical evaluation of a miniature strain-gauge transducer for monitoring intracranial pressure. Neurosurgery 1995; 36:1137-40; discussion 1140-1. [PMID: 7643993 DOI: 10.1227/00006123-199506000-00011] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In 25 patients, we evaluated the accuracy of a new miniature strain-gauge transducer developed for the measurement of intracranial pressure (ICP). The ICP in each patient was measured with the intraventricular, miniature strain-gauge transducer, and that value was compared with the ICP measured with a ventriculostomy catheter coupled to an external strain-gauge transducer. From the two monitors, 2218 simultaneous measurements of ICP were obtained. The average ICP measured with the miniature strain-gauge transducer was 15.9 +/- 10.0 mm Hg (range, -3 to 104 mm Hg). The ICP measured with the ventriculostomy-catheter transducer averaged 15.4 +/- 10.1 mm Hg (range, -9 to 104 mm Hg). A highly significant correlation was found over the wide range of pressures observed (n = 2218, r = 0.97, P < 0.001). The average difference between the two measurements of the ICP was 0.5 +/- 2.6 mm Hg, and the differences were equally positive and negative, demonstrating no consistent bias. The two values for the ICP were within 2 mm Hg of each other on 63% of the measurements and within 4 mm Hg of each other on 89% of the measurements. The average zero drift of the miniature strain-gauge transducer, measured at ambient pressure after removal of the catheter, was 0.2 +/- 0.5 mm Hg. The results indicate that this miniature strain-gauge transducer is highly accurate and stable and that it is a reliable alternative to a ventriculostomy for monitoring the ICP.
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Contant CF, Robertson CS, Crouch J, Gopinath SP, Narayan RK, Grossman RG. Intracranial pressure waveform indices in transient and refractory intracranial hypertension. J Neurosci Methods 1995; 57:15-25. [PMID: 7791362 DOI: 10.1016/0165-0270(94)00106-q] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Analysis of data obtained by continuous computerized monitoring of intracranial pressure (ICP) in 109 adult patients with severe head trauma was performed to examine the pattern of change in indices of the ICP waveform. Indices derived from direct measurement of the ICP wave and obtained from a Fast Fourier Transform (FFT) were examined. Concurrent physiologic measurements were made. Two types of intracranial hypertension (ICH) were defined for comparison. 'Transient intracranial hypertension' occurred when an abrupt rise in ICP was followed by a return to below 25 mm Hg (n = 63). Increases in ICP that were progressive and led to neurologic deterioration and death were termed 'refractory intracranial hypertension' (n = 18). During transient ICH heart rate, arterial pressure, end-tidal carbon dioxide and jugular venous oxygen saturation all increased, while these measures either were unchanged or decreased during refractory ICH. The pulse amplitude of the ICP wave increased in both types of ICHtn. Other changes in the waveform indices were consistent with this change in pulse amplitude. HFC responded differently to the two types of changes, with an increase during the transient changes and a decrease during the refractory changes. The differences in changes in physiologic measurements as ICH occurred in the 2 groups suggest that in refractory ICH cerebral blood flow is maintained against the mounting ICP, while in transient ICH the hypertension is caused by an increase in cerebral blood flow. The waveform indices do not discriminate between the two types of changes.
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Abstract
Between 1984 and 1992, 131 patients underwent two-team synchronous oesophagectomy for carcinoma. Some 95 per cent of tumours were successfully resected by this technique. In 5 per cent of patients the tumour was found to be irresectable at operation and gastric bypass was performed. The overall operative mortality rate was 8 per cent and the pulmonary complication rate 10 per cent. The actuarial survival rate was 55 per cent at 1 year, 22 per cent at 3 years and 16 per cent at 5 years. When compared with the traditional two-stage Lewis approach, two-team synchronous oesophagectomy was significantly faster (mean 222 versus 282 min), but was not significantly different with respect to blood loss, transfusion requirement, pulmonary complications or operative mortality rate. Patients undergoing two-team oesophagectomy had a significantly shorter hospital stay than those receiving the two-stage procedure (mean 16 versus 24 days).
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Cherian L, Peek K, Robertson CS, Goodman JC, Grossman RG. Calorie sources and recovery from central nervous system ischemia. Crit Care Med 1994; 22:1841-50. [PMID: 7956290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVES Glucose is the primary substrate for the energy requirements of the nervous system. Nevertheless, administration of glucose to critically ill patients with central nervous system trauma may have adverse effects on their neurologic recovery. The purpose of this study was to evaluate the effects of other sources of nonprotein calories on spinal cord lactate accumulation and on electrophysiologic recovery after a period of severe spinal cord ischemia. DESIGN Two randomized, blinded studies were performed: one of glycolytic energy substrates (fructose, xylitol, sorbitol, glycerol) and one of ketogenic energy substrates (beta-hydroxybutyrate, acetate, butyrate). SETTING College teaching hospital laboratory. SUBJECTS New Zealand albino rabbits (weight 3.5 to 4.5 kg). INTERVENTIONS After infusion of the randomly assigned treatment, temporary ischemia was produced in the lumbosacral spinal cord by occluding the abdominal aorta with a balloon catheter. MEASUREMENTS AND MAIN RESULTS Blood concentrations of glucose, lactate, pyruvate, and ketone bodies and spinal cord dialysate concentration of lactate were measured before and after infusion of the assigned treatment, and during ischemia and during the first 2 hrs after reperfusion. Spinal somatosensory evoked potentials were recorded during ischemia to assure a similar severity of ischemia in all animals and during the first 2 hrs after reperfusion as a measure of electrophysiologic recovery. Infusion of the glycolytic nutrients xylitol and fructose increased blood glucose and lactate concentrations, and resulted in increased lactate accumulation in the spinal cord during ischemia and resulted in a significantly poorer recovery of the spinal somatosensory evoked potential than infusion of saline. Infusion of sorbitol and glycerol did not have these adverse effects in the doses administered. None of the ketogenic nutrients increased blood glucose concentration or increased lactate accumulation in the spinal cord during ischemia when compared with infusion of saline. Infusion of butyrate and acetate caused arterial hypotension and resulted in a poorer recovery of the spinal somatosensory evoked potential than saline. Infusion of beta-hydroxybutyrate did not have an adverse effect on blood pressure or on evoked potential recovery. CONCLUSIONS Glycerol, sorbitol, and beta-hydroxybutyrate deserve further evaluation as potential nonprotein calorie sources in patients with neurologic injury. Xylitol and fructose are not suitable since these substrates resulted in hyperglycemia and increased lactate accumulation in the central nervous system, and had detrimental effects on electrophysiologic recovery after ischemia. The short-chain fatty acids (acetate and butyrate) also had adverse effects on electrophysiologic recovery after ischemia, probably because of their hypotensive effects when given intravenously, rather than from the effects of their metabolism.
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208
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Ritter AM, Robertson CS. Cerebral metabolism. Neurosurg Clin N Am 1994; 5:633-45. [PMID: 7827475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
An intricate relationship normally exists between cerebral metabolism and energy substrate supply because of the brain's high substrate demand and limited storage capacity. In head-injured patients, this balance can be disrupted. The brain parenchyma directly involved by the injury is hypometabolic in respect to glucose and oxygen, whereas peri-injury tissue may have an elevated metabolic rate.
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Cherian L, Robertson CS, Contant CF, Bryan RM. Lateral cortical impact injury in rats: cerebrovascular effects of varying depth of cortical deformation and impact velocity. J Neurotrauma 1994; 11:573-85. [PMID: 7861449 DOI: 10.1089/neu.1994.11.573] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Intracranial pressure (ICP), blood pressure (BP), cerebral perfusion pressure (CPP), and cortical perfusion (LDF) of the contralateral parietal cortex were measured after cortical impact injury in 36 rats. Changes in these physiologic parameters were compared using analysis of variance to a group of 11 rats who received a sham impact. In one series of experiments, the velocity and duration of the impact injury were kept constant, and the severity of the injury was determined by varying the depth of cortical deformation from 2 to 3 mm. The peak pressure inside the skull was directly related to the depth of cortical deformation, and was 93 +/- 16, 182 +/- 18, and 268 +/- 57 mm Hg with the 2, 2.5, and 3 mm deformation, respectively, when the impact velocity was 5 m/sec. With the 2 mm depth injury, there was a transient decrease in BP (p < 0.05) and a 12% decrease in LDF after the impact. With the 2.5 mm depth injury, a small transient increase in ICP and decrease in BP and a 30% decrease in LDF occurred (p < 0.05). ICP then gradually increased throughout the 8 h experiment, becoming significantly greater than the sham-injured animals by 5 h after the impact. LDF gradually returned toward normal throughout the experiment. With the 3 mm depth injury, a marked transient increase in ICP (p < 0.05) and BP (p < 0.05) occurred immediately after the impact. The increase in BP lasted < 5 min, and subsequently the BP decreased to approximately 50 mm Hg for the rest of the experiment. The initial marked increase in ICP lasted 15 min and then remained 5-10 mm Hg higher (p < 0.05) than in the sham-injured animals for the rest of the experiment. LDF decreased by an average of 50% (p < 0.05) immediately after the impact and remained lower than that of the sham-injured animals for the rest of the experiment. In another series of experiments, the depth of cortical deformation was kept constant at 2.5 mm, and the severity of the injury was determined by varying the velocity from 1 to 5 m/sec. The peak ICP was significantly related to the impact velocity, averaging 45 +/- 12, 66 +/- 9, and 182 +/- 18 mm Hg with the 1, 3, and 5 m/sec impact injuries, respectively. The 1 m/sec impact had no effect on ICP and only a transient decrease in BP.(ABSTRACT TRUNCATED AT 400 WORDS)
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Goodman JC, Cherian L, Bryan RM, Robertson CS. Lateral cortical impact injury in rats: pathologic effects of varying cortical compression and impact velocity. J Neurotrauma 1994; 11:587-97. [PMID: 7861450 DOI: 10.1089/neu.1994.11.587] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Direct lateral cortical impact through the intact leptomeninges using a pneumatically driven piston produces increasingly severe pathophysiologic derangements with increasing cortical deformation. We studied the histopathologic correlates of cortical impact injury produced by 2 mm, 2.5 mm, and 3 mm deformation in the rat at 5 m/sec. Additionally, the effect of impact velocity at a 2.5 mm deformation was assessed at 1 m/sec, 3 m/sec, and 5 m/sec. The brains were examined 14 days after injury. Cortical contusion maximum cross-sectional area, volume, and the percentage CA1 and CA3 hippocampal neuronal loss correlate with cortical deformation and impactor velocity. Contusion volume increased with increasing cortical deformation. Deformations of 2, 2.5, and 3 mm at 5 m/sec produced contusion volumes of 4.59, 8.9, and 21.68 mm3, respectively. At a fixed cortical deformation of 2.5 mm, contusion volume increased with increasing impact velocity. Impact velocities of 1, 3, and 5 m/sec produced contusion volumes of 5.79, 7.42, and 8.9 mm3, respectively. Hippocampal CA3 neuronal loss increased with increasing cortical deformation. Deformations of 2, 2.5, and 3 mm at 5 m/sec produced neuronal loss of 29%, 48.3%, and 79.5%, respectively. At a fixed cortical deformation of 2.5 mm, hippocampal CA3 neuronal loss increased with increasing impact velocity. Impact velocities of 1, 3, and 5 m/sec produced neuronal loss of 18.25%, 33.75%, and 48.3%, respectively. Hippocampal CA1 neuronal loss was also seen and paralleled cortical deformation and impact velocity. Cortical deformation and impact velocity are critical parameters in producing cortical contusion and must be considered when comparing results using this model.
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211
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Robertson CS, Chung SC, Woods SD, Griffin SM, Raimes SA, Lau JT, Li AK. A prospective randomized trial comparing R1 subtotal gastrectomy with R3 total gastrectomy for antral cancer. Ann Surg 1994; 220:176-82. [PMID: 8053740 PMCID: PMC1234357 DOI: 10.1097/00000658-199408000-00009] [Citation(s) in RCA: 247] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The authors determined if more radical surgery with extended lymphadenectomy improves the results of gastrectomy in patients with adenocarcinoma of the gastric antrum. SUMMARY BACKGROUND DATA The overall survival in patients with gastric cancer is disappointing. Improved survival has been reported by Japanese authors. Whether this is because of a higher number of early gastric cancers in the Japanese series, different biologic behavior in Asians, or the adoption of radical surgery with lymphadenectomy remains unclear. METHODS R1 subtotal gastrectomy with omentectomy and R3 total gastrectomy (omentectomy, splenectomy, distal pancreatectomy, lymphatic clearance of the celiac axis, and skeletonization of vessels in the porta hepatis) were evaluated in a prospective, randomized comparison. RESULTS Fifty-five patients were randomized--25 to the R1 group and 30 to the R3 group. The two groups were comparable for age, sex, tumor size, TNM stage, and length of follow-up. The R3 group had a longer operating time (140 vs. 260 min; p < 0.05), a greater transfusion requirement (0 vs. 2 units, p < 0.05) and a longer hospital stay (8 vs. 16 days; p < 0.05) (medians; Mann-Whitney U test). The only postoperative death was in the R3 group and was caused by intra-abdominal sepsis. Fourteen patients in the R3 group developed left subphrenic abscesses. There were no major complications in the R1 group. Overall survival was significantly better in the R1 group (median survival estimated by Kaplan-Meier method, 1511 vs. 922 days, p < 0.05, log-rank test). CONCLUSIONS R3 total gastrectomy can be performed with a low mortality, but it has a high morbidity because of intra-abdominal sepsis. The data do not support the routine use of R3 total gastrectomy for treatment of patients with antral cancer.
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Chiou-Tan FY, Lenz ML, Robertson CS, Grabois M. Pharmacologic treatment of autonomic dysreflexia in the rat. Am J Phys Med Rehabil 1994; 73:251-5. [PMID: 7913819 DOI: 10.1097/00002060-199407000-00005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Autonomic dysreflexic hypertension occurs in up to 80% of spinal cord injury patients with lesions thoracic level 6 or higher. Pharmacologic agents directed at each part of the autonomic dysreflexic circuit were tested for efficacy in a rat model. Guanethidine (15 mg/kg intraperitoneally), alpha-methyl-paratyrosine (20 mg/kg intraperitonally), propranolol (3 mg/kg intraperitonally) and control were each tested on groups of three rats with intrinsic control blood pressure measurements. Results show an increase of 15 +/- 5 mm Hg diastolic pressure in control animals compared with no detectable increase with guanethidine or alpha-methyl-paratyrosine. There was an 11 +/- 2 mm Hg increase in diastolic pressure with propranolol. In conclusion, screening drug trials show that the ganglionic blocking agent, guanethidine, and competitive tyrosine uptake precursor, alpha-methyl-paratyrosine, effectively blocked dysreflexic hypertension, whereas the beta-blocker, propranolol, did not.
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213
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Gopinath SP, Robertson CS, Contant CF, Hayes C, Feldman Z, Narayan RK, Grossman RG. Jugular venous desaturation and outcome after head injury. J Neurol Neurosurg Psychiatry 1994; 57:717-23. [PMID: 8006653 PMCID: PMC1072976 DOI: 10.1136/jnnp.57.6.717] [Citation(s) in RCA: 345] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Early experience with continuous monitoring of jugular venous oxygen saturation (SjvO2) suggested that this technology might allow early identification of global cerebral ischaemia in patients with severe head injury. The purpose of the present study was to examine the relationship between episodes of jugular venous desaturation and neurological outcome. One hundred and sixteen severely head-injured patients had continuous monitoring of SjvO2 during days 1-5 after injury. Episodes of jugular venous desaturation (SjvO2 < 50% for more than 10 minutes) were prospectively identified, and the incidence of desaturation was correlated with neurological outcome: 77 episodes of desaturation occurred in 46 of the 116 patients; 27 had one episode and 19 had multiple episodes of desaturation. The causes of these episodes were systemic (n = 36), cerebral (n = 35), or both (n = 6). Most of the episodes were less than 1 hour in duration, and it is probable that many of them would not have been detected without continuous measurement of SjvO2. Episodes of desaturation were most common on day 1 after injury, and were twice as common in patients with a reduced cerebral blood flow as in patients with a normal or elevated cerebral blood flow. The occurrence of jugular venous desaturation was strongly associated with a poor neurological outcome. The percentage of patients with a poor neurological outcome was 90% with multiple episodes of desaturation and 74% in patients with one desaturation, compared to 55% in patients with no episodes of desaturation. When adjusted for all co-variates that were found to be significant, including age, Glasgow coma score, papillary reactivity, type of injury, lowest recorded cerebral perfusion pressure, and highest recorded temperature, the incidence of desaturation remained significantly associated with a poor outcome. Although a cause and effect relationship with outcome cannot be established in this study, the data suggest that monitoring SvO2 might allow early identification and therefore treatment of many types of secondary injury to the brain.
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214
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Simpson RK, Contant CF, Robertson CS, Goodman JC. Spectral analysis of corticomotor evoked potentials in spinal cord injury. Part 2. Chronic studies. Neurol Res 1993; 15:373-8. [PMID: 7907403 DOI: 10.1080/01616412.1993.11740166] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Corticomotor evoked potentials (CMEPs) have been suggested to accurately reflect neurological function, particularly with regard to the integrity of the spinal cord. However, the utility of these potentials to evaluate graded, chronic injury has received little attention. Frequency analysis has been suggested by the authors to be a method of simplifying interpretation of these complex signals. Ischaemic spinal cord injuries were produced in rabbits causing mild, moderate, or severe neurological deficits. CMEPs were recorded before, during, immediately following, and three days after injury. Alterations in the features of the power spectra reflected the degree of neurological injury. CMEP power spectra may predict neurological outcome and augment currently used electrodiagnostic tests.
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Simpson RK, Contant CF, Robertson CS, Goodman JC. Spectral analysis of corticomotor evoked potentials in spinal cord injury. Part 1. Acute studies. Neurol Res 1993; 15:367-72. [PMID: 7907402 DOI: 10.1080/01616412.1993.11740165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A model of graded spinal cord injury using ischaemia has been developed by using balloon occlusion of the abdominal aorta in rabbits. This model has been used to test pharmacological agents thought to provide protection against spinal cord injury based on changes in corticomotor evoked potentials (CMEPs). These highly reproducible signals are percutaneously recorded from the spinal cord in response to cortical stimulation and accurately reflect the degree of residual spinal cord function. The present study focused on the power spectra of CMEPs to clarify alterations in post-injury signals. This added dimension of previously unreported CMEP analysis will augment future applications of the current model.
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216
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Muszynski CA, Robertson CS, Goodman JC, Henley CM. DFMO reduces cortical infarct volume after middle cerebral artery occlusion in the rat. J Cereb Blood Flow Metab 1993; 13:1033-7. [PMID: 8408313 DOI: 10.1038/jcbfm.1993.131] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Ornithine decarboxylase (ODC), a key enzyme in polyamine biosynthesis, is induced in ischemic tissue and may mediate vasogenic edema and delayed neuronal death. We determined the effects of alpha-difluoromethylornithine (DFMO), a specific inhibitor of ODC, on infarct size and ODC activity in a rat model of transient focal ischemia. DFMO blocked the ischemia-induced increase in ODC and significantly reduced infarct volumes by 57-45%, depending upon the treatment regimen. These studies suggest that polyamine metabolism plays a role in the development of cerebral infarction after focal ischemia and that DFMO may be useful in limiting injury after a stroke.
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Abstract
Ciliated metaplasia (CM) of gastric mucosa is common in Japanese individuals but rare in whites. We studied 36 consecutive gastrectomies from Chinese individuals for the presence of CM. The gastrectomies were performed for adenocarcinoma (n = 22), benign ulcer (n = 13), and malignant lymphoma (n = 1). Ciliated metaplasia was found in 16 (44.4%) of the stomachs, with equal distribution between male and female patients. Ciliated metaplasia was present in 11 cases (50%) of adenocarcinoma and in five cases (38.5%) of benign ulcer, the difference being statistically insignificant. Contrary to previous studies, there was no increased frequency of CM in gastric mucosa harboring an intestinal-type adenocarcinoma compared with those with non-intestinal-type tumors. Ciliated metaplasia always co-existed with intestinal metaplasia. Colonization by Helicobacter pylori was not associated with an increased incidence of CM. In five cases (22.7%) of adenocarcinoma ciliated tumor cells were found, and all of these cases showed CM in the gastric mucosa. In one of these cases the whole tumor was composed of glands formed by ciliated cells. In the other cases there was a morphologically different nonciliated component. The cilia in the tumor cells showed light microscopic and ultrastructural changes identical to those of the cilia seen in CM affecting the nonneoplastic gastric mucosa. This study documents for the first time the co-existence of CM and ciliated adenocarcinoma in the same stomach. It is concluded that in the Hong Kong Chinese population CM is commonly present in gastric mucosa harboring an adenocarcinoma or benign ulcer. Adenocarcinomas with ciliated cells are strongly associated with CM.
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218
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Gopinath SP, Cherian L, Robertson CS, Narayan RK, Grossman RG. Evaluation of a microsensor intracranial pressure transducer. J Neurosci Methods 1993; 49:11-5. [PMID: 8271823 DOI: 10.1016/0165-0270(93)90104-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This report describes the results of a laboratory evaluation of a new device for monitoring intracranial pressure (ICP), consisting of a miniature pressure transducer mounted on a pressure sensing diaphragm. In in vitro tests, 6 microsensor transducers were monitored for drift at pressures of 10 mmHg and 20 mmHg. The maximal drift of any of the transducers was 1 mmHg over 9 days. In in vivo tests, the ICP measurement obtained with the microsensor transducer correlated well with pressures recorded from a catheter in the cisternal magna with a Statham transducer over a wide range of ICP values (n = 511, r = 0.998, P < 0.001). If these laboratory findings can be duplicated in clinical studies, this microsensor transducer may be a useful alternative to the ventriculostomy catheter and other currently used devices for monitoring ICP.
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219
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Simpson RK, Robertson CS, Goodman JC. Glycine: an important potential component of spinal shock. Neurochem Res 1993; 18:887-92. [PMID: 8103919 DOI: 10.1007/bf00998273] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Amino acid neurotransmitters (AANTs) play a major role in maintenance of muscle tone. Abnormal AANT concentrations are associated with hyper- or hypotonic states. Flaccidity from spinal shock commonly occurs after spinal cord injury (SCI) and may be associated with changes in AANT concentrations. Ischemic SCIs created in the lumbar region of rabbits by intraaortic balloon occlusion produced spastic or flaccid injuries. Microdialysis sampling of AANTs from the injured segmental structures was done 3 days after SCI. Evoked potentials were used to monitor spinal cord stability. No significant changes in AANT levels occurred in the spastic or flaccid group after 4 hour sampling. However, flaccid animals had baseline glycine levels 2-3 times higher (p < 0.001) than spastic animals or controls. High concentrations of the inhibitory AANT glycine is associated with flaccidity following SCI, or spinal shock, but not spasticity. Glycinergic compounds directed toward suppression of excess muscle tone deserve further study.
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Gopinath SP, Robertson CS, Grossman RG, Chance B. Near-infrared spectroscopic localization of intracranial hematomas. J Neurosurg 1993; 79:43-7. [PMID: 8315468 DOI: 10.3171/jns.1993.79.1.0043] [Citation(s) in RCA: 120] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Near-infrared spectroscopy (NIRS) of the cerebral hemispheres, applied transcranially through the intact scalp and skull, was evaluated for its ability to detect the presence of an intracranial hematoma in 46 head-injured patients. In 40 patients intracranial hematomas (22 subdural, 10 epidural, eight intracerebral) were identified on computerized tomography (CT); in all 40 cases, NIRS demonstrated greater absorption of light at 760 nm on the side of the hematoma. The mean difference in optical density (OD) between the hemisphere with the hematoma and the normal hemisphere was 0.99 +/- 0.30 for epidural hematomas, 0.87 +/- 0.31 for subdural hematomas, but only 0.41 +/- 0.11 for intracerebral hematomas. In 36 patients, the asymmetry in OD resolved after surgical evacuation of the hematoma or with spontaneous resorption of the hematoma. Four patients who developed postoperative or delayed hematomas exhibited persistence of the asymmetry in OD. Six patients had only diffuse injuries and exhibited only minor differences in OD between the hemispheres, similar to 10 patients in the control group with no head injury. It appears that NIRS is useful in the initial examination of the head-injured patient, as an adjunct to CT, and in following patients postoperatively in the intensive care unit.
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Evans JD, Robertson CS, Clague MB, Snow MH, Booth H. Severe lower gastrointestinal haemorrhage from cytomegalovirus ulceration of the terminal ileum in a patient with AIDS. THE EUROPEAN JOURNAL OF SURGERY = ACTA CHIRURGICA 1993; 159:373-5. [PMID: 8104501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Feldman Z, Contant CF, Pahwa R, Goodman JC, Robertson CS, Narayan RK, Grossman RG. The relationship between hormonal mediators and systemic hypermetabolism after severe head injury. THE JOURNAL OF TRAUMA 1993; 34:806-16. [PMID: 8315675 DOI: 10.1097/00005373-199306000-00010] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The relationships of hormonal mediators to the systemic hypermetabolism and catabolism of head injury were studied in 15 patients with severe head injuries. Resting energy expenditure (REE), urinary nitrogen balance, and plasma glucose concentration were measured daily for the first 2 weeks after injury as the major indicators of hypermetabolism. These dependent variables were correlated with daily measurements of urinary epinephrine, norepinephrine, metanephrine, normetanephrine, dopamine, and cortisol, and with plasma levels of insulin, glucagon, and C-reactive protein. Urinary catecholamine and cortisol excretion were markedly elevated in these patients throughout the 2 weeks of study. Catecholamine excretion peaked between days 7 and 10, whereas cortisol excretion tended to be highest on day 5 after injury. Urinary levels of norepinephrine, normetanephrine, and cortisol were highest in the two patients with Glasgow Coma Scale scores of 4. Plasma insulin and glucagon concentrations were elevated on day 1 after injury and tended to increase throughout the 2-week period of study. The variables significantly associated with REE were the severity of injury, reflected by the GCS score, the urinary excretion of norepinephrine during the first 2 days after injury, and the urinary excretion of epinephrine and norepinephrine during days 3 to 7 after injury. A negative nitrogen balance was associated with the urinary excretion of epinephrine and norepinephrine, with caloric balance, and with plasma C-reactive protein during days 1 and 2 after injury. During days 3 to 7, a negative nitrogen balance was associated with the urinary excretion of epinephrine and norepinephrine and with caloric balance, and during days 8 to 14, a negative nitrogen balance was associated primarily with urinary cortisol excretion.
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Simpson RK, Robertson CS, Goodman JC. Spinal epidural corticomotor evoked potentials as a predictor of outcome from ischaemic myelopathy. Neurol Res 1993; 15:104-8. [PMID: 8099203 DOI: 10.1080/01616412.1993.11740118] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Corticomotor evoked potentials have been suggested to accurately reflect neurological function, particularly with regard to the integrity of the spinal cord. However, the utility of these potentials to evaluate graded, chronic injury has received little attention. Using a rabbit model of ischaemic spinal cord injury we recorded corticomotor evoked potentials before, during, immediately after, and three days after producing an ischaemic spinal cord injury by inflating an intraaortic balloon. The animals sustained a stable mild, moderate, or severe neurological deficit. All ischaemic injured animals demonstrated near loss of the corticomotor evoked potential after the timed balloon occlusion period. Mildly injured animals did not demonstrate significant differences in corticomotor evoked potentials at reperfusion of three days post injury, when compared to controls. However, moderate and severely injured animals revealed significant reduction in late latency component amplitudes by > 50% and > 90%, respectively, when compared to controls. Changes in corticomotor evoked potential features are associated with altered neurological function after graded spinal cord injury.
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Robertson CS, Evans DF, Ledingham SJ, Atkinson M. Cisapride in the treatment of gastro-oesophageal reflux disease. Aliment Pharmacol Ther 1993; 7:181-90. [PMID: 8485271 DOI: 10.1111/j.1365-2036.1993.tb00088.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Prokinetic agents are being used increasingly in medical therapy for gastro-oesophageal reflux disease (GERD). This study examined the effect of 10 mg q.d.s., oral cisapride, or placebo, taken for 12 weeks, on 48 patients with symptoms and endoscopic evidence of GERD. Objective evaluation of benefit was obtained by endoscopy and biopsy, oesophageal manometry, acid reflux provocation test and 24-h oesophageal pH monitoring. Cisapride significantly increased lower oesophageal sphincter pressure (P = 0.003) against baseline and also against placebo, in patients (n = 9) with an hypotensive lower oesophageal sphincter pressure (P < 0.01). The frequency of dyspeptic symptoms was significantly improved in the cisapride group (P = 0.03). Antacid intake, global evaluation of symptoms and a VAS score for symptoms were all better than placebo but failed to reach significance (global evaluation by patients, P = 0.07). Overall, there was no significant improvement in oesophagitis at either 6 weeks (P < 0.05 > 0.3) or 12 weeks (P = 0.07). However, if patients with grades I and II oesophagitis at entry were excluded, cisapride had a significantly greater effect than placebo, 6 weeks (P = 0.05), 12 weeks (P = 0.04). In those with oesophageal ulceration, cisapride was significantly more effective than placebo in inducing healing. Gastro-oesophageal reflux was very variable on both 24-h pH monitoring and acid reflux provocation test. In spite of a 50% decrease in acid exposure on 24-h pH monitoring (cisapride group, mean % pH < 4 day: entry 18.9%, 12 weeks 9.6%), there were no significant intra- or intergroup differences for percentage of time < pH 4, or frequency and duration of episodes, neither pre- or post-prandially, day or night, except for the number of post-prandial episodes during acid reflux provocation tests, which decreased significantly more with cisapride than with placebo (P < 0.05). Thus, oral cisapride when taken for 12 weeks promoted healing of oesophagitis and improved symptoms in patients with GERD; although an increase in lower oesophageal sphincter pressure was observed and a reduction in acid reflux was measured, no significant decrease of acid exposure was seen.
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Abstract
In a search for past or present infection with herpes viruses, serum antibody titres to herpes simplex type 1 virus, cytomegalovirus, and varicella-zoster virus were measured by complement fixation test in 58 patients with achalasia. Serum was also taken from 40 age and sex matched patients without oesophageal symptoms who formed a control group. All titres were low, and those for herpes simplex type 1 virus and cytomegalovirus did not differ in the achalasia patients and the controls. However, the incidence of varicella-zoster virus antibodies was significantly greater in the achalasia than in the control group (p < 0.05). Using oesophageal tissue containing myenteric plexus removed at the time of cardiomyotomy in nine patients with achalasia, in situ DNA hybridisation showed evidence of varicella-zoster virus in three, but all were negative for the other two viruses. No positive results were obtained for herpes simplex type 1 virus, cytomegalovirus, or varicella-zoster virus in oesophageal tissue from 20 patients undergoing oesophageal resection for diseases other than achalasia. The incidence of positivity for varicella-zoster virus was significantly increased in the achalasia group compared with the controls (p < 0.02). The findings indicate that varicella-zoster virus DNA may persist in the oesophageal myenteric plexus in some patients with achalasia and raise the possibility that this virus is of aetiological importance in achalasia.
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Simpson RK, Robertson CS, Goodman JC. Segmental recovery of amino acid neurotransmitters during posterior epidural stimulation after spinal cord injury. THE JOURNAL OF THE AMERICAN PARAPLEGIA SOCIETY 1993; 16:34-41. [PMID: 8093898 DOI: 10.1080/01952307.1993.11735882] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Epidural spinal cord stimulation (SCS) has been used as an effective method for managing pain and spasticity for over two decades. However, the mechanisms of these beneficial effects are largely unknown. Since neurotransmitters are likely to be involved, we examined the relationship between SCS and local segmental amino acid release into the spinal cord extracellular space. Microdialysis was performed during continuous epidural SCS in animals subjected to ischemic spinal cord injury. Recovery of amino acid neurotransmitters from stimulated, injured animals was compared to that from a control group. Evoked potentials from the cortex and spinal cord were recorded to insure adequate stimulation and stable cord function. A significant increase in the concentrations of glycine and taurine was seen before, during, and after 90 minutes of continuous stimulation and was independent of the degree of injury. Levels of the other putative amino acid neurotransmitters were not significantly elevated. These results suggest that amelioration of pain or spasticity by epidural SCS may result from maintenance of post-injury elevation in baseline glycine and taurine levels.
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Oliver SE, Robertson CS, Logan RF. Oesophageal cancer: a population-based study of survival after treatment. Br J Surg 1992; 79:1321-5. [PMID: 1283106 DOI: 10.1002/bjs.1800791226] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The survival of patients with oesophageal cancer diagnosed during the period 1982-1985 in Nottingham has been studied. Of 496 patients identified from endoscopy, histopathology and hospital activity analysis records, 268 (171 men) lived in the catchment area and had primary oesophageal cancer. Compared with previous studies the proportion of adenocarcinoma (35 per cent) was twice that expected, although survival was similar (hazard rate ratio at 2 years 1.0 (95 per cent confidence interval (c.i.) 0.8-1.4)) whether a squamous cell carcinoma or adenocarcinoma was present. Based on the original treatment intention, surgery was attempted in 34 per cent of cases and was associated with a median survival from diagnosis of 293 (95 per cent c.i. 232-367) days, with 41, 19 and 11 per cent surviving 1, 2 and 3 years respectively. Radical radiotherapy was attempted in 13 per cent of patients and was associated with a median survival of 190 (95 per cent c.i. 136-253) days, with 14, 6 and 6 per cent surviving 1, 2 and 3 years. Intubation alone was performed in 40 per cent of patients, of whom 44 per cent were aged over 75 years and 29 per cent had evidence of metastases, compared with 13 and 11 per cent respectively of those undergoing surgery or radical radiotherapy. The median survival for intubation alone was 100 (95 per cent c.i. 81-122) days, with 6, 3 and 0 per cent of patients surviving 1, 2 and 3 years respectively. Although patients treated surgically had the longest survival, these data indicate that overall survival after any active intervention is modest. Intubation alone is a reasonable option in those not suitable for surgery; randomized trials are needed to compare intubation with new methods of palliation.
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Robertson CS, Contant CF, Gokaslan ZL, Narayan RK, Grossman RG. Cerebral blood flow, arteriovenous oxygen difference, and outcome in head injured patients. J Neurol Neurosurg Psychiatry 1992; 55:594-603. [PMID: 1640238 PMCID: PMC489173 DOI: 10.1136/jnnp.55.7.594] [Citation(s) in RCA: 137] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cerebral blood flow (CBF) and other physiological variables were measured repeatedly for up to 10 days after severe head injury in 102 patients, and CBF levels were related to outcome. Twenty five of the patients had a reduced CBF [mean (SD) 0.29 (0.05) ml/g/min]; 47 had a normal CBF, (0.41 (0.10) ml/g/min); and 30 had a raised CBF (0.62 (0.14) ml/g/min). Cerebral arteriovenous oxygen differences were inversely related to CBF and averaged 2.1 (0.7) mumol/ml in the group with reduced CBF, 1.9 (0.5) mumol/ml in the group with normal CBF, and 1.6 (0.4) mumol/ml in the group with raised CBF. Patients with a reduced CBF had a poorer outcome than patients with a normal or raised CBF. Mortality was highest in patients with a reduced CBF, and was 32% at three months after injury, whereas only 21% of the patients with a normal CBF and 20% of the patients with a raised CBF died. There were no differences in the type of injury, initial score on the Glasgow Coma Scale, mean intracranial pressure (ICP), highest ICP, or the amount of medical treatment required to keep the ICP less than 20 mm Hg in each group. Systemic factors did not significantly contribute to the differences in CBF among the three groups. A logistic regression model of the effect of CBF on neurological outcome was developed. When adjusted for variables which were found to be significant confounders, including age, initial Glasgow Coma Score, haemoglobin concentration, cerebral perfusion pressure and cerebral metabolic rate of oxygen, a reduced CBF remained significantly associated with an unfavourable neurological outcome.
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Atkinson M, Iftikhar SY, James PD, Robertson CS, Steele RJ. The early diagnosis of oesophageal adenocarcinoma by endoscopic screening. Eur J Cancer Prev 1992; 1:327-30. [PMID: 1467783 DOI: 10.1097/00008469-199206000-00009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Oesophageal carcinoma has a very poor prognosis unless detected at a pre-symptomatic stage. This can only be done by screening and patients with Barrett's columnar lined epithelium of the oesophagus (CLO) are high risk candidates for an endoscopic screening programme. Surveillance studies in CLO patients, when reviewed, showed that the incidence of adenocarcinoma was between 1 in 52 and 1 in 81 patient years, with a mean of 1 in 76. This paper describes the Nottingham experience with an endoscopic screening programme that was established in 1976. To date it has detected four adenocarcinomas at a mean cost similar to that of detecting breast cancer by screening.
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Robertson CS, Goodman JC, Grossman RG. Blood flow and metabolic therapy in CNS injury. J Neurotrauma 1992; 9 Suppl 2:S579-94. [PMID: 1613815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A hypermetabolic state, consisting of increased resting energy expenditure, excessive protein wasting, and hyperglycemia, occurs in patients with a severe head injury. The hypermetabolism can affect survival by rapidly resulting in protein-calorie malnutrition (increased energy expenditure and protein wasting) and may adversely affect neurological recovery by altering the microenvironment of the injured brain (hyperglycemia).
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Robertson CS, Contant CF, Narayan RK, Grossman RG. Cerebral blood flow, AVDO2, and neurologic outcome in head-injured patients. J Neurotrauma 1992; 9 Suppl 1:S349-58. [PMID: 1588626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A reduced cerebral blood flow (CBF) and a widened arteriovenous oxygen difference (AVDO2) almost always have been associated with a poor neurologic outcome. The literature on this relationship is reviewed. A logistic regression analysis model of the effect of CBF on neurologic outcome was developed, which was adjusted for various confounding factors. CBF remained significantly associated with neurologic outcome-despite these adjustments.
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Sheinberg M, Kanter MJ, Robertson CS, Contant CF, Narayan RK, Grossman RG. Continuous monitoring of jugular venous oxygen saturation in head-injured patients. J Neurosurg 1992; 76:212-7. [PMID: 1472169 DOI: 10.3171/jns.1992.76.2.0212] [Citation(s) in RCA: 350] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The continuous measurement of jugular venous oxygen saturation (SjvO2) with a fiberoptic catheter is evaluated as a method of detecting cerebral ischemia after head injury. Forty-five patients admitted to the hospital in coma after severe head injury had continuous and simultaneous monitoring of SjvO2, intracranial pressure, arterial oxygen saturation, and end-tidal CO2. Cerebral blood flow, cerebral metabolic rates of oxygen and lactate, arterial and jugular venous blood gas levels, and hemoglobin concentration were measured every 8 hours for 1 to 11 days. Whenever SjvO2 dropped to less than 50%, a standardized protocol was followed to confirm the validity of the desaturation and to establish its cause. Correlation of SjvO2 values obtained by catheter and with direct measurement of O2 saturation by a co-oximeter on venous blood withdrawn through the catheter was excellent after in vivo calibration when there was adequate light intensity at the catheter tip (176 measurements: r = 0.87, p less than 0.01). A total of 60 episodes of jugular venous oxygen desaturation occurred in 45 patients. In 20 patients the desaturation value was confirmed by the co-oximeter. There were 33 episodes of desaturation in these 20 patients, due to the following causes: intracranial hypertension in 12 episodes, hypocarbia in 10, arterial hypoxia in six, combinations of the above in three, systemic hypotension in one, and cerebral vasospasm in one. The incidence of jugular venous oxygen desaturations found in this study suggests that continuous monitoring of SjvO2 may be of clinical value in patients with head injury.
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Feldman Z, Kanter MJ, Robertson CS, Contant CF, Hayes C, Sheinberg MA, Villareal CA, Narayan RK, Grossman RG. Effect of head elevation on intracranial pressure, cerebral perfusion pressure, and cerebral blood flow in head-injured patients. J Neurosurg 1992; 76:207-11. [PMID: 1730949 DOI: 10.3171/jns.1992.76.2.0207] [Citation(s) in RCA: 172] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The traditional practice of elevating the head in order to lower intracranial pressure (ICP) in head-injured patients has been challenged in recent years. Some investigators argue that patients with intracranial hypertension should be placed in a horizontal position, the rationale being that this will increase the cerebral perfusion pressure (CPP) and thereby improve cerebral blood flow (CBF). However, ICP is generally significantly higher when the patient is in the horizontal position. This study was undertaken to clarify the issue of optimal head position in the care of head-injured patients. The effect of 0 degree and 30 degrees head elevation on ICP, CPP, CBF, mean carotid pressure, and other cerebral and systemic physiological parameters was studied in 22 head-injured patients. The mean carotid pressure was significantly lower when the patient's head was elevated at 30 degrees than at 0 degrees (84.3 +/- 14.5 mm Hg vs. 89.5 +/- 14.6 mm Hg), as was the mean ICP (14.1 +/- 6.7 mm Hg vs. 19.7 +/- 8.3 mm Hg). There was no statistically significant change in CPP, CBF, cerebral metabolic rate of oxygen, arteriovenous difference of lactate, or cerebrovascular resistance associated with the change in head position. The data indicate that head elevation to 30 degrees significantly reduced ICP in the majority of the 22 patients without reducing CPP or CBF.
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Wilding IR, Davis SS, Hardy JG, Robertson CS, John VA, Powell ML, Leal M, Lloyd P, Walker SM. Relationship between systemic drug absorption and gastrointestinal transit after the simultaneous oral administration of carbamazepine as a controlled-release system and as a suspension of 15N-labelled drug to healthy volunteers. Br J Clin Pharmacol 1991; 32:573-9. [PMID: 1954073 PMCID: PMC1368633 DOI: 10.1111/j.1365-2125.1991.tb03954.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
1. Plasma drug concentrations after a single oral administration of a suspension of carbamazepine (CBZ) and a 20/200 CBZ Oros osmotic pump system were measured in eight healthy male volunteers. The oral suspension contained 100 mg CBZ labelled with the stable isotope nitrogen-15, whilst the Oros contained 200 mg unlabelled CBZ. Plasma concentrations of [15N]-CBZ and CBZ were measured simultaneously by gas chromatography-mass spectrometry. 2. The position of the CBZ Oros (labelled with indium-111) in the gastrointestinal tract was followed by gamma scintigraphy. Plasma drug concentrations after the two treatments were used to relate pharmacokinetic with transit data. 3. The Oros was taken after breakfast and gastric emptying occurred between 1.1- greater than h post-dosing (median, 5.3 h). Small intestinal transit times ranged from 1.5- greater than 3.6 h, with a median of 2.2 h. There were wide individual variations in colonic transit, and the total transit time ranged from 10-60 h (median, 22 h). 4. Relative systemic bioavailability of CBZ from the Oros was reduced compared with that from the suspension (mean dose normalised AUC ratio = 0.69 +/- 0.17; mean dose-normalised AUC ratio = 0.85 +/- 0.13, allowing for actual release from the Oros system). 5. The in vivo absorption of drug into the systemic circulation from the Oros was estimated using the Wagner-Nelson method. This showed that absorption of CBZ was rapid when the Oros was present in the stomach and small intestine, the rate being determined by the release of drug from the system.(ABSTRACT TRUNCATED AT 250 WORDS)
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Evans DF, Robertson CS, Morris DL, Ledingham SJ, Doran J, Hardcastle JD. An objective long-term evaluation of the Angelchik antireflux prosthesis. Ann R Coll Surg Engl 1991; 73:355-60. [PMID: 1759764 PMCID: PMC2499447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
This paper reports the long-term results of the Angelchik antireflux prosthesis (ACP) in Nottingham from October 1981 to December 1989 in 42 patients with gastrooesophageal reflux disease (GORD). Pre- and postoperative oesophagoscopy, pH monitoring, acid reflux provocation test (ARPT), manometry and symptom evaluation were documented to assess the benefits of the procedure. There were no operative complications, dysphagia was the commonest postoperative problem and necessitated the removal of four ACPs. In most patients, dysphagia resolved within 1 year of surgery. Recurrence of reflux symptoms resulted in revision surgery in two patients. In general, reflux control was good. We believe that the ACP is a good antireflux operation which gives good long-term reflux and symptom control in the majority of patients. The removal rate of 15% in our series is of some concern but may be due in part to operator skills. The long-term objective follow-up has shown a trend towards a return of GOR and this and the unknown long-term effects of implanted silicone may limit the use of this procedure to the more elderly patient.
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Robertson CS. Inflammatory cells and the hypermetabolism of head injury. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1991; 118:205. [PMID: 1919292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Feldman Z, Contant CF, Robertson CS, Narayan RK, Grossman RG. Evaluation of the Leeds prognostic score for severe head injury. Lancet 1991; 337:1451-3. [PMID: 1675328 DOI: 10.1016/0140-6736(91)93137-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
According to the Leeds scale for identifying severely head injured patients, death can be predicted with certainty within 12 hours of admission if a patient has a score higher than 13. The withdrawal of treatment from such patients has considerable moral and legal implications. Therefore, to test the reliability of the Leeds scale, it was applied to two patient populations with severe head injuries (479 retrospectively, 131 prospectively). In both groups the scale failed to predict mortality with 100% accuracy: in the first group, 16 of 23 (69.6%) of the patients with a score of more than 13 (and therefore predicted to die) died, and 380 (83.3%) of 456 patients with scores of 13 or less survived; the data for the second group are 6/10 (60%) and 98/121 (81%), respectively. The findings suggest that the Leeds prediction model is not infallible and should be applied cautiously when making decisions about the early termination of care in severely head injured patients.
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Evans DF, Robertson CS, Ledingham SJ, Kapila L. Esophageal pH monitoring for gastroesophageal reflux: a United Kingdom study. J Pediatr Surg 1991; 26:682-5. [PMID: 1941457 DOI: 10.1016/0022-3468(91)90010-q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Esophageal pH monitoring is the accepted standard for the investigation of gastroesophageal reflux (GER) in adults. A postal questionnaire was sent to 912 United Kingdom paediatric physicians & surgeons. Five hundred forty-seven (61%) replied, with 124 (22.7%) currently using the technique, mostly in conjunction with barium swallow and/or esophagoscopy. The use of pH monitoring to quantify GER was also accepted in principal as being the best determinant of reflux by a further 186 (34%), but as yet was unavailable in their hospitals. Pediatricians were also questioned as to their management of children with GER. The majority were treated medically with a variety of antireflux medication, with only 237 (42%) referring cases for surgery.
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Robertson CS, Simpson RK. Neurophysiologic monitoring of patients with head injuries. Neurosurg Clin N Am 1991; 2:285-99. [PMID: 1821742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Despite new technologic developments designed to analyze the brain's electrical activity, monitoring the electroencephalogram or evoked potentials has not yet provided important information with regard to acute management of patients with head injury. Measurement of cerebral blood flow as well as jugular oxygen saturation is of more practical importance. Particularly when monitored continuously, these measures can provide useful information about the use of hyperventilation and control of elevated systemic arterial pressure.
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Simpson RK, Contant CF, Fischer DK, Cech DA, Robertson CS, Narayan RK. The influence of diabetes mellitus on outcome from subarachnoid hemorrhage. DIABETES RESEARCH (EDINBURGH, SCOTLAND) 1991; 16:165-9. [PMID: 1802482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Diabetes mellitus (DM) has been shown to be a risk factor for subarachnoid hemorrhage (SAH). However, the influence of this disease on outcome from SAH has not been adequately studied. We retrospectively reviewed 150 patients with SAH, including 22 with and 128 without DM. Our results indicate that pre-existing DM does not significantly influence outcome from SAH when examined in conjunction with other chronic diseases and epidemiological factors.
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Simpson RK, Robertson CS, Goodman JC, Halter JA. Recovery of amino acid neurotransmitters from the spinal cord during posterior epidural stimulation: a preliminary study. THE JOURNAL OF THE AMERICAN PARAPLEGIA SOCIETY 1991; 14:3-8. [PMID: 1673708 DOI: 10.1080/01952307.1991.11735828] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Continuous posterior epidural spinal cord stimulation (SCS) has been an effective method for treating spasticity. The mechanisms of SCS include activation of inhibitory segmental neuronal systems and suprasegmental structures that produce inhibitory descending control. The neurochemical correlates of the mechanism of action have not been clearly defined. Microdialysis of the spinal cord extracellular space in an in vivo preparation during continuous epidural SCS was performed. The recovery of amino acid neurotransmitters, aspartate, glutamate, gamma-aminobutyric acid (GABA), glycine, and taurine from stimulated animals was compared to non-stimulated animals. Evoked potentials from the cortex and spinal cord of the stimulated animals were recorded to insure that there had been adequate epidural stimulation and normal segmental cord function. A significant increase in the concentration of glycine was seen after 90 minutes of continuous stimulation. The levels of the other amino acids were not significantly elevated. These results suggest that amelioration of spasticity with epidural SCS may involve enhanced glycine release, the major inhibitory neurotransmitter of the spinal cord.
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Simpson RK, Robertson CS, Goodman JC. Release of segmental amino acid neurotransmitters in response to peripheral afferent and motor cortex stimulation: a pilot study. Life Sci 1991; 49:PL113-8. [PMID: 1682779 DOI: 10.1016/0024-3205(91)90140-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The role of amino acid (AA) neurotransmitters in the spinal cord has been primarily studied using in vitro preparations and histochemical methods. The technology necessary to estimate AA levels in an intact animal has only recently become available. Such an investigation could yield valuable information regarding the segmental neurochemical environment. We measured the release of AAs into the rabbit lumbar spinal cord in response to sciatic nerve and transcranial stimulation with stereotaxically placed microdialysis catheters. Samples were obtained periodically during 90 minutes of continuous stimulation of either the left or right sciatic nerve, or motor cortex. Quantification of gamma-amino butyric acid (GABA), aspartate, glutamate, glycine, and taurine was performed using high pressure liquid chromatography (HPLC). Adequate neural excitation was verified by recording somatosensory evoked potentials (SSEPs) or corticomotor evoked potentials (CMEPs). Sensory activation at intensities sufficient to activate small and large diameter peripheral fibers of the ipsilateral (to the microdialysis probe) sciatic nerve produced a significant change only in segmental glycine levels. Contralateral sciatic nerve stimulation failed to evoke a significant elevation of AAs. In addition, a significant increase in the release of glycine and taurine was measured after 90 minutes of transcranial stimulation. SSEP and CMEP components repeatedly showed adequate activation of primary afferent, descending motor fiber pathways, and segmental interneuron pools during dialysis sampling. Our data are consistent with the hypothesis that suprasegmental influence over peripheral afferent and motor activity may be, in part, through these amino acid neurotransmitters in the rabbit lumbar spinal cord.
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Simpson RK, Robertson CS, Goodman JC. Segmental release of amino acid neurotransmitters from transcranial stimulation. Neurochem Res 1991; 16:89-94. [PMID: 1675777 DOI: 10.1007/bf00965834] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The present study used microdialysis techniques in an intact rabbit model to measure the release of amino acids within the lumbar spinal cord in response to transcranial electrical stimulation. Dialysis samples from the extracellular space were obtained over a stimulation period of 90 minutes and were examined using high pressure liquid chromatography. Neuronal excitation was verified by recording corticomotor evoked potentials (CMEPs) from the spinal cord. A significant increase in the release of glycine and taurine compared to sham animals was measured after 90 minutes of transcranial stimulation. Glutamate and aspartate release was not significantly elevated. GABA concentrations were consistently low. CMEP components repeatedly showed adequate activation of descending fiber pathways and segmental interneuron pools during dialysis sampling. Since glycine, and to a lesser extent taurine, have been shown to inhibit motor neuron activity and are closely associated with segmental interneuron pools, suprasegmental modulation of motor activity may be, in part, through these inhibitory amino acid neurotransmitters in the rabbit lumbar spinal cord.
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Robertson CS, Goodman JC, Narayan RK, Contant CF, Grossman RG. The effect of glucose administration on carbohydrate metabolism after head injury. J Neurosurg 1991; 74:43-50. [PMID: 1984505 DOI: 10.3171/jns.1991.74.1.0043] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The role of intravenous infusion of glucose in limiting ketogenesis and the effect of glucose on cerebral metabolism following severe head injury were studied in 21 comatose patients. The patients were randomly assigned to alimentation with or without glucose. Systemic protein wasting, arterial concentrations of energy substrates, and cerebral metabolism of these energy substrates were monitored for 5 days postinjury. Both groups were in negative nitrogen balance, and had wasting of systemic proteins despite substantial protein intake. Blood and cerebrospinal fluid (CSF) glucose concentrations were highest on Day 1, but remained higher than normal fasting levels on all days of study, even in the patients who received no exogenous glucose. Although there were no differences in blood or CSF glucose concentrations in the two groups of patients, the glucose group had higher plasma insulin levels, with a mean +/- standard deviation of 14.8 +/- 7.3 microU/ml compared to 10.3 +/- 4.2 microU/ml in the saline group. The blood concentrations of beta-hydroxybutyrate, acetoacetate, pyruvate, glycerol, and the free fatty acids were higher in the saline group than in the glucose group. Cerebral oxygen consumption was similar in the two groups, while the cerebral metabolism of glucose and of the ketone bodies was dependent on whether glucose was administered. In the glucose group, glucose was the only energy substrate utilized by the brain. In the saline group, the ketone bodies beta-hydroxybutyrate and acetoacetate replaced glucose to the extent of 16% of the brain's total energy production. Cerebral lactate production and CSF lactate concentration were lower in the saline group. These studies suggest that administration of glucose during the early recovery period of severe head injury is a major cause of suppressed ketogenesis, and may increase production of lactic acid by the traumatized brain by limiting the availability of nonglycolytic energy substrates.
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Simpson RK, Contant CF, Fischer DK, Cech DA, Robertson CS, Narayan RK. Epidemiological characteristics of subarachnoid hemorrhage in an urban population. J Clin Epidemiol 1991; 44:641-8. [PMID: 2066744 DOI: 10.1016/0895-4356(91)90025-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Several risk factors for unfavorable outcome from subarachnoid hemorrhage (SAH) have been identified. The prevalence of such risk factors varies among ethnic groups and among men and women. The influence of ethnic background and gender as factors in the outcome after SAH has not been adequately studied and is the focus of the present investigation. Outcome in 145 consecutive patients was dichotomized as good and moderately disabled vs severely disabled, vegetative, and dead. A multiple logistic regression model was used to examine the factors of gender, ethnic group (white and non-white), age, admission neurological grade, pre-existing hypertension, and intravenous drug abuse. Our data reveal that hypertensive, white males, with a history of intravenous drug abuse, have a high risk of unfavorable outcome following SAH. These observations are important for the design and interpretation of future studies relating to SAH.
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Abstract
Tumor necrosis factor (TNF) is a cytokine which mediates protein wasting in pathological states by promoting the catabolism of visceral tissues and skeletal muscle. The role that TNF plays in nitrogen wasting following head injury was studied by measuring TNF in the serum of 21 patients with severe head injury. Parallel measurements of TNF and urinary nitrogen excretion were performed on days 1, 3, and 5 after head injury. TNF values after head injury ranged from 65 pg/ml to 7500 pg/ml, with a mean of 1147 pg/ml, compared to control values of serum TNF of less than 38 pg/ml. The mean daily urinary nitrogen loss was 13 g/day with a range of 2.8 to 27.6 g/day, and the mean nitrogen balance was -5.8 g with a range of +4.6 to -19.1 g. While both serum TNF levels and nitrogen loss were increased after head injury, the elevation of TNF did not correlate strongly with nitrogen wasting.
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Rowles JM, Robertson CS, Roberts SN. General surgical injuries in survivors of the M1 Kegworth air crash. Nottingham, Leicester, Derby, Belfast Study Group. Ann R Coll Surg Engl 1990; 72:378-81. [PMID: 2241058 PMCID: PMC2499276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The general surgical consequences of the M1 Kegworth air crash are described. Considering the severe nature of the injuries sustained by the survivors, surprisingly few required general surgical intervention. Intra-abdominal injuries were rare despite the abdomen's apparent vulnerability to injury; only five laparotomies were performed. However, 30 (34%) of survivors demonstrated significant bruising from lap belts and 13 patients had haematuria. The majority of operations carried out were orthopaedic related.
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Oliver SE, Robertson CS, Logan RF, Sokal M, Pearson JC, Atkinson M. What does radiotherapy add to survival over endoscopic intubation alone in inoperable squamous cell oesophageal cancer? Gut 1990; 31:750-2. [PMID: 2370011 PMCID: PMC1378528 DOI: 10.1136/gut.31.7.750] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The place of radiotherapy in the management of squamous cell oesophageal cancer remains uncertain. Survival of oesophageal cancer patients from the Nottingham area in the years 1982-5 was reviewed. Surgical resection was attempted in 44 of 131 patients with squamous cell oesophageal cancer. Among the remainder 32 had endoscopic intubation alone, 27 had radical radiotherapy alone (six) or combined with endoscopic intubation (21), and 28 had other treatment combinations including surgical intubation and palliative radiotherapy. Patients treated by intubation alone had a mean age of 75 years. They were significantly older and metastases were more common (31%) in this group than in patients treated with radiotherapy (mean age 69 years), of whom 11% had metastases. Some 34% (11 of 32) of patients treated by intubation alone died within 30 days of diagnosis and were therefore not eligible for radiotherapy. Beyond 30 days, survival in the radiotherapy group (median survival 188 days; 95% confidence limits 133-253) was not significantly greater than that for the group treated by intubation alone (median survival 98 days (73-154)). The radiotherapy patients had a median hospital stay of 46 days compared with 23 days for the patients treated by intubation alone. In patients with squamous cell oesophageal cancer unsuitable for surgery, the survival advantage associated with radiotherapy and intubation is small and does not compensate for the extra morbidity and prolonged hospital stay. A controlled trial of radiotherapy in these patients is now needed.
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