Consumptive coagulopathy complicating juvenile angiofibroma

OBJECTIVE: To investigate the incidence and clinical significance of deranged clotting results among patients with juvenile (nasopharyngeal) angiofibroma. METHODS: Twenty consecutive patients treated for juvenile angiofibroma between March 1998 and July 2002 in whom preoperative coagulation tests were performed were selected. Results were compared with normal laboratory values, and clinical and histological records were retrospectively analysed. RESULTS: Four out of 20 patients were found to have abnormal tests, consistent with concurrent consumptive coagulopathies. One patient was found to have a raised D-dimer level. This resolved following removal of the lesion. CONCLUSIONS: The association between larger arterio-venous malformations and disseminated intravascular coagulopathy is well described (Kasabach-Merritt syndrome). Our findings suggest that low-grade consumptive coagulopathies may also complicate smaller juvenile angiofibromas, implying that preoperative coagulation screening tests may have a role in ensuring optimal perioperative haemostasis.     

Assessment of individual quality of life using the SEIQoL-DW in older medical patients

BACKGROUND: Many hospital admissions aim to optimize quality of life (QoL). However, the standard medical clerking does not systematically record QoL items. AIM: To examine whether the current disease-based clerking could be supplemented in older people with QoL information. DESIGN: Survey of non-elective admissions aged > or = 65 years. METHODS: Participants (n = 60) were interviewed on day 3-5 of their admission. QoL was measured using the SEIQoL-DW and the SF36 (version 2). Cognitive and physical function were also assessed. Aspects of feasibility and acceptability were explored, and the potential clinical benefits of the information investigated. RESULTS: Mean patient age was 81 years; 36 (60%) were female. Forty-five completed the SEIQoL-DW, (mean time 37.7 min), of whom 17 experienced practical difficulties drawing the cue levels, and 25 had difficulty manipulating the direct weighting device of the SEIQoL-DW. However, the assessment process was judged as acceptable, and elicited more subjective information than was recorded in medical and nursing notes. Doctors considered the individual QoL information potentially useful for planning discharge and follow-up. DISCUSSION: The SEIQoL-DW is probably too time-consuming for standard medical clerking. However, as it was judged acceptable by patients, and according to medical staff, gives potentially valuable information, there may be circumstances in which its use is worthwhile.     

The effect of mechanically-induced cricoid force on lower oesophageal sphincter pressure in anaesthetised patients

In the United Kingdom, cricoid force is central to upper airway management in obstetric and emergency anaesthesia. A reduction in oesophageal barrier pressure (OBP) in these patients may increase regurgitation risk. This study investigated whether the application of cricoid force to anaesthetised patients reduced lower oesophageal sphincter pressure (LOSP) and consequently OBP. Anaesthesia was induced in 29 patients using a standard protocol. An oesophageal balloon catheter was inserted and gastric trace identified. The catheter was withdrawn incrementally and pressure readings recorded at each position before and during the application of 30 N cricoid force, with a sudden rise in pressure indicating lower oesophageal sphincter position. Oesophageal barrier pressure was calculated as the difference between LOSP and gastric pressure. Application of cricoid force significantly reduced OBP without influencing gastric pressure (p < 0.001). The use of cricoid force may increase the risk of gastroesophageal reflux in anaesthetised patients.     

Experimental pain models reveal no sex differences in pentazocine analgesia in humans

BACKGROUND: Accumulating evidence suggests that there are sex differences in analgesic responses to opioid agonists. Several studies using an oral surgery pain model have reported more robust analgesia to kappa-agonist-antagonists (e.g., pentazocine, nalbuphine, butorphanol) among women than among men. However, evidence of sex differences in kappa-agonist-antagonist effects from studies of experimentally induced pain in humans is lacking. METHODS: Therefore, the analgesic effects of intravenous pentazocine (0.5 mg/kg) were determined in healthy women (n = 41) and men (n = 38) using three experimental pain models: heat pain, pressure pain, and ischemic pain. Each pain procedure was conducted before and after double-blind administration of both pentazocine and saline, which occurred on separate days in counterbalanced order. RESULTS: Compared with saline, pentazocine produced significant analgesic responses for all pain stimuli. However, no sex differences in pentazocine analgesia emerged. Effect sizes for the sex differences were computed; the magnitude of effects was small, and an equal number of measures showed greater analgesia in men than in women. Also, analgesic responses were not highly correlated across pain modalities, suggesting that different mechanisms may underlie analgesia for disparate types of pain. CONCLUSIONS: These findings indicate significant analgesic responses to pentazocine in both men and women across multiple experimental pain assays, and the absence of sex differences contrasts with previous data from the oral surgery model. The most likely explanation for the discrepancy in results is that of differences in the pain assays. These findings are important because they suggest that sex differences in opioid analgesia may be specific to certain types of pain.     

Maternal insufflation during the second trimester equivalent produces hypercapnia, acidosis, and prolonged hypoxia in fetal sheep

BACKGROUND: Anecdotal reports suggest that the second trimester is the safest time to conduct a laparoscopic procedure on a pregnant patient, but this supposition has not been tested empirically. METHODS: Previously instrumented preterm sheep (total n = 8) at gestational day 90 (term, 145 days) were anesthetized and then insufflated with carbon dioxide for 60 min at a pressure of 15 mmHg. Cardiovascular parameters were continuously recorded while blood gas status was determined before and at 15-min intervals during and up to 2 h after insufflation. RESULTS: Insufflation produced minimal maternal blood gas or cardiovascular changes except for a significant reduction in uterine blood flow. The decrease in perfusion increased fetal arterial blood partial pressure of carbon dioxide and decreased fetal pH, oxygen saturation, and oxygen content; there was also progressive fetal hypotension and bradycardia. After manually deflating the ewe, uterine blood flow returned to normal, and the fetal partial pressure of carbon dioxide and pH changes resolved within 1 h. However, fetal oxygen saturation and content remained depressed, and fetal cardiovascular status continued to decline during the 2-h postinsufflation monitoring period. CONCLUSION: Previous studies with near-term sheep determined that carbon dioxide pneumoperitoneum produces respiratory acidosis but does not decrease fetal oxygenation. In contrast, the current findings indicate that in the preterm fetus, insufflation-induced hypercapnia and acidosis are accompanied by prolonged fetal hypoxia and cardiovascular depression. This result suggests that additional work should be conducted to confirm the presumed safety of conducting minimally invasive procedures during the second trimester.     

Endotoxin has an indirect vasodilatory effect on isolated human skeletal muscle arterioles

BACKGROUND: Septic shock and its effects are a major cause of mortality in the intensive care environment. The exact effect and mechanism of endotoxin has yet to be fully described. With a better understanding of this process, better clinical tools could be developed to treat these patients. HYPOTHESIS: Endotoxin has no direct effect on human skeletal muscle microvasculature and requires the release of an endothelial-derived factor to produce the vasodilation seen in gram-negative sepsis. DESIGN: Benchtop research using an isolated arteriole model with controlled exposure to endotoxin. SETTING: University medical center. METHODS: First-order arterioles (approximately 150- micro m diameter) were isolated from human cremasteric muscles and pressurized to physiologic levels before exposure to an endotoxin-rich effluent with and without an upstream conduit vessel (superficial epigastric vein). The vasodilatory effect was measured with videomicroscopy and compared with control samples. MAIN OUTCOME MEASURES: Mean vessel diameter and percentage of loss in tone. RESULTS: When compared with controls, the isolated arteriole had no significant response when exposed to endotoxin alone (3.5% change in basal tone). When the endotoxin was allowed to pass over an upstream conduit vessel, the arteriole showed marked dilation (14.2% loss of basal tone). CONCLUSIONS: This study demonstrates that endotoxin has no direct vasodilatory effect on human skeletal muscle arterioles, but it is the release of an endothelial factor from the upstream conduit vessels that produces the loss of tone in the microvasculature. Further research is ongoing to characterize the factors involved (nuclear factor-kappaB, tumor necrosis factor alpha, and interleuklin 6) for possible clinical intervention (antioxidants, cyclosporine, and nitric oxdide synthase inhibitors).     

Survival of patients with periampullary carcinoma is predicted by lymph node 8a but not by lymph node 16b1 status

BACKGROUND: The aim of this study was to assess the impact of metastatic disease in lymph nodes 8a and 16b1 (as defined by the Japanese Pancreas Society) on survival in patients with periampullary malignancy. METHODS: Patients undergoing resection for primary pancreatic ductal adenocarcinoma or intrapancreatic bile duct adenocarcinoma were identified from a prospective database (September 1997-May 2003). RESULTS: Thirteen of 54 and ten of 44 evaluable patients had metastatic involvement of lymph nodes 8a and 16b1 respectively. Metastatic involvement of lymph node 8a was associated with a significantly shorter median survival (197 versus 470 days; P = 0.003) but metastatic involvement of lymph node 16b1 did not affect survival (457 versus 503 days; P = 0.185). Multivariate analysis showed lymph node 8a status to be the strongest predictor of outcome (P = 0.006). Median survival of those with metastatic lymph node 8a was not significantly different from that of 81 patients with overt metastatic periampullary cancer at the time of diagnosis (98 days; P = 0.072) CONCLUSION: Lymph node 8a was an independent prognostic factor in patients with periampullary malignancy, but lymph node 16b1 was not. Survival in those with metastatic lymph node 8a was not significantly different from that in patients with metastatic disease at presentation. Preoperative determination of lymph node 8a status may have important implications in selecting patients for treatment.     

Oxidative stress in hypertension and chronic kidney disease: role of angiotensin II

Angiotensin II, via the type 1 (AT1) receptor, stimulates oxidative stress. The vasculature, interstitium, juxtaglomerular apparatus, and the distal nephron in the kidney express nicotinamide adenine dinucleotide phosphate (NADPH) oxidase that generates superoxide anion, which is an important component of angiotensin II-induced oxidative stress. The angiotensinogen gene is stimulated by NF-kappaB activation, which is sensitive to the redox ratio, providing a positive feedback loop that can upregulate angiotensin II production. Oxidative stress can accompany hypertension in many models, including the spontaneously hypertensive rat (SHR), angiotensin II-infused rats, renovascular hypertension, and the deoxycorticosterone acetate (DOCA) salt model of hypertension. AT1 receptor antagonists can abrogate the effects of angiotensin II on oxidative stress, thus providing an important mechanistic insight onto the renal protective effects of these agents in conditions associated with angiotensin II excess.