Reversible cerebral perfusion alterations in children with transient mutism after posterior fossa surgery

Mutism is an infrequent and transitory complication observed following posterior fossa surgery. Patients become mute in the immediate postoperative period, with restoration of speech within a few weeks in the absence of additional neurological alterations. The anatomical structures thought to be involved are the connections between the cerebellar dentate nucleus, the ventrolateral nucleus of the contralateral thalamus and the supplementary motor area. In an attempt to understand the pathophysiology of this syndrome, and to depict the perfusion of different brain areas semiquantitatively, in two children who had become mute after posterior fossa surgery we performed a Tc99M-HM-PAO SPECT study during the period of mutism and again when normal speech had returned. In one patient, who had a left cerebellar astrocytoma, the SPECT study showed a marked reduction of cerebral perfusion in the right fronto-parietal region, and in the other, who had a medulloblastoma, a left fronto-temporo-parietal perfusion alteration was observed. When the patients regained normal speech, the follow-up SPECT studies revealed normalization of the cerebral perfusion. This study demonstrates the occurrence of a focal dysfunction of cerebral perfusion in children with cerebellar mutism after posterior fossa surgery. These observations are useful in extending our understanding of the pathophysiology of this postoperative clinical syndrome. Received: 12 September 1997 Revised: 17 November 1997     

Presentation, treatment, and multivariate analysis of risk factors for obstructive and perforative colorectal carcinoma

BACKGROUND: It is known that emergency surgery for colorectal cancer is associated with high morbidity and mortality. The aim of this study was to assess the presentation, treatment, and outcome of patients with complicated colorectal cancer. Risk factors for morbidity and mortality were also evaluated. METHODS: From 1991 to 2002, the medical records of 107 consecutive patients undergoing emergency surgery for obstructing or perforating colorectal carcinoma were retrospectively reviewed. Information regarding patient and tumor characteristics, treatment, and outcome was recorded. Risk factors were assessed by multivariate analysis. RESULTS: Eighty-three patients (78%) had complete obstruction and 24 (22%) had perforation. Overall and major complications occurred in 70% and 34%, respectively. The mortality rate was 15%. Independent risk factors for major morbidity were perioperative blood transfusion and high American Society of Anesthesiologists (ASA) class, whereas those for mortality were older age and high Acute Physiology and Chronic Health Evaluation II (APACHE II) score. CONCLUSIONS: Emergency surgery for complicated colorectal carcinoma carries high rates of morbidity and mortality. To achieve improvements in outcome, intensive treatment after surgery in patients with risk factors is recommended.     

Low calorie commercial sugar is a sensitive marker of glomerular filtration rate

BACKGROUND: Glomerular filtration rate (GFR) in humans and animals might be determined with precision by measuring the clearance of an ideal marker, such as inulin. However, the use of inutest, an inulin analog, is limited by its cost and accessibility. The present study tested whether low calorie commercial sugar (LC sugar) can be used to measure GFR during normal and renal dysfunction. METHODS: Two groups of 6 male Wistar rats weighing 300 to 350 g were included. One group was treated with a daily dose of cyclosporine (CsA) 30 mg/kg subcutaneously for 7 days and the other group was formed by nontreated control rats. In one half of each group, GFR was evaluated by using inutest and in the other half by using LC sugar. GFR was also evaluated by using a wide LC sugar plasma concentration range in an additional group. RESULTS: In nontreated rats, the mean GFR evaluated with LC sugar was 2.2 +/- 0.1 mL/min. This value is equal to that obtained with inutest: 2.3 +/- 0.1 mL/min. CsA administration produced a significant reduction of renal blood flow and renal function. The GFR reduction induced by CsA was similarly determined by both LC sugar and inutest to be at 1.0 +/- 0.2 and 1.1 +/- 0.2 mL/min (P= NS), respectively. In addition, GFR did not change when LC sugar plasma concentration gradually increased. CONCLUSION: Our results show that in both normal and pathophysiologic conditions, LC sugar is a good marker of GFR similar to the gold standard inutest.     

Concordance between qualitative and quantitative cultures in burned patients. Analysis of 2886 cultures

OBJECTIVE: To determine the concordance between superficial cultures (SC) and quantitative cultures (QC) in the diagnosis of wound infection in burn patients. METHOD: Sample: All SC and QC taken from the same patient, site and during the same surgery were analysed. Variables: On the SC, the microorganism (MO) and its amount defined subjectively by the microbiologist was recorded (negative, very low, low, regular and abundant). On the QC, the MO and its amount were expressed as colony forming units per gram of tissue (CFUs/g). Statistics: Kappa index of agreement beyond chance; Wilcoxon and Kruskall-Wallis for continuous variables and chi(2) for categorical variables were used with a p<0.05 indicating statistical significance. RESULTS: One thousand four hundred and forty three pairs of cultures were analyzed. The concordance between SC and QC (Kappa index) was 52%. On the SC, only when the microbiologist subjectively informed "abundant" MOs there was a significant difference (p<0.0001). There were 6.1% of QCs with more than 10(5) CFUs/g and the most frequent MOs isolated were: S. aureus (27.9%), E. coli (11.6%), P. aeruginosa (11.6%), E. faecalis (11.6%) and S. epidermidis (7.0%). CONCLUSIONS: SC has a moderate concordance with the QC showing a low reliability between the two methods. The subjective information given by the microbiology technician in the SC is not precise. A study in which the two methods be compared blindly against the reference standard, in a prospective cohort of patients, it is needed to discriminate which of two methods it is the most accurate one determining sensitivity and specificity.     

Adequacy of laboratory simulation of in-line skater falls

PURPOSE: Currently most laboratory simulation of distal radius fractures and wrist injuries has been with axial limb loading or vertical drop technique. To better assess the contribution of horizontal velocity in momentum in the development of wrist injury and wrist fracture we have compared forces and fracture patterns for fall simulations involving strictly vertical impacts with those that incorporated horizontal momentum in fresh-frozen upper extremities. METHODS: The premise for testing was based on a forward fall onto the palmar surface of an outstretched arm. A 45 degrees-incline impact device was used to model the horizontal and vertical velocity components of a skater fall at a representative speed. Sled mass was 26.2 kg. A 45.5-kg vertical impact system furnished contrasting data and represented prior state-of-the-art technology. Drop heights were adjusted to compensate for discrepancy in sled mass. Measurements from either impact system included vertical and horizontal forces and kinetic energy at impact. Fracture patterns were assessed radiographically. Nine trials were conducted with the incline device and 11 trials were conducted with the vertical impact system. RESULTS: The fracture rate was substantially higher for vertical impacts versus incline impacts (82% vs 33%). The rate of carpal fractures also was higher. Vertical and horizontal forces were similar statistically although slightly greater for vertical impacts. Kinetic energy, however, was 3 times greater for incline impacts than for vertical impacts. These kinetic parameters support the argument that the incline impacts should have resulted in far greater injury. CONCLUSIONS: The data suggest horizontal momentum changes limb loading. We submit that published methods for modeling skater falls have failed to provide a true simulation of the event in question.     

Hand involvement in paraneoplastic syndrome: a case report

Cutaneous paraneoplastic syndromes are skin and mucous membrane changes that are associated with cancer. We report a previously healthy 76-year-old man who developed marked finger and thumb contracture, pain, and hypersensitivity of both hands who was diagnosed subsequently as having gastric carcinoma with colonic metastasis. After the gastrointestinal tumors were resected the finger and thumb contracture lessened and the pain eased. Both the temporal relationship between the changes in the hand and the neoplasm and the improvement after resection suggest a paraneoplastic syndrome.     

High correlation of human immunodeficiency virus type-1 viral load measured in dried-blood spot samples and in plasma under different storage conditions

BACKGROUND: To measure HIV-1 RNA concentration requires venous extraction of blood, use of RNAase-free materials, and transport in a cold chain, which makes difficult the management of samples in developing countries. We evaluated the utility of the determination of HIV-1 RNA concentration in blood samples dried on filter paper (DBS) and subjected to different conditions, as contrasted with determination in plasma. METHODS: HIV-1 RNA concentration was determined in HIV-infected patients in DBS and in plasma samples. Samples were subjected to the following: DBS were stored at 4, 22, and 37 degrees C for 1, 3, and 7 days; samples from patients from four regions of Mexico were mailed to a reference laboratory; DBS were sent under environmental conditions; and plasma samples were sent frozen. HIV-1 RNA concentrations were determined by NucliSens in DBS and by Amplicor test in plasma. RESULTS: HIV-1 RNA concentration determined in DBS subjected to different temperatures and times had a significant correlation (r=0.99) with those obtained in plasma. When compared with values in plasma, Kappa agreement coefficients of values in DBS stored for 7 days at 4, 22, and 37 degrees C were 0.98, 0.83, and 0.94, respectively. Quantification of HIV-1 RNA in 108 DBS mailed from remote areas with different climates demonstrated significant correlation with those obtained in plasma (r=0.95; p <0.001). CONCLUSIONS: DBS is a simple and reliable method to measure HIV-1 RNA concentration, especially when samples are mailed from remote areas to a reference center. This collection method is an economic and suitable alternative for use in developing countries.     

Supplemental perioperative oxygen and the risk of surgical wound infection: a randomized controlled trial

Context  Supplemental perioperative oxygen has been variously reported to halve or double the risk of surgical wound infection. Objective  To test the hypothesis that supplemental oxygen reduces infection risk in patients following colorectal surgery. Design, Setting, and Patients  A double-blind, randomized controlled trial of 300 patients aged 18 to 80 years who underwent elective colorectal surgery in 14 Spanish hospitals from March 1, 2003, to October 31, 2004. Wound infections were diagnosed by blinded investigators using Centers for Disease Control and Prevention criteria. Baseline patient characteristics, anesthetic treatment, and potential confounding factors were recorded. Interventions  Patients were randomly assigned to either 30% or 80% fraction of inspired oxygen (FIO₂) intraoperatively and for 6 hours after surgery. Anesthetic treatment and antibiotic administration were standardized. Main Outcome Measures  Any surgical site infection (SSI); secondary outcomes included return of bowel function and ability to tolerate solid food, ambulation, suture removal, and duration of hospitalization. Results  A total of 143 patients received 30% perioperative oxygen and 148 received 80% perioperative oxygen. Surgical site infection occurred in 35 patients (24.4%) administered 30% FIO₂ and in 22 patients (14.9%) administered 80% FIO₂ (P=.04). The risk of SSI was 39% lower in the 80% FIO₂ group (relative risk [RR], 0.61; 95% confidence interval [CI], 0.38-0.98) vs the 30% FIO₂ group. After adjustment for important covariates, the RR of infection in patients administered supplemental oxygen was 0.46 (95% CI, 0.22-0.95; P = .04). None of the secondary outcomes varied significantly between the 2 treatment groups. Conclusions  Patients receiving supplemental inspired oxygen had a significant reduction in the risk of wound infection. Supplemental oxygen appears to be an effective intervention to reduce SSI in patients undergoing colon or rectal surgery. Trial Registration  ClinicalTrials.gov Identifier: NCT00235456      

Perioperative enteral nutrition

Enteral nutrition, as demonstrated by the many published papers, is not only safer and cheaper than parenteral supply of nutrients, but modulates an exaggerated cytokine response related to surgical trauma that leads to an increase in intestinal permeability, bacterial translocation and infection. The aim of enteral nutrition is to reduce the impact of cytokines on surgical patients and the related infectious complications. Via the enteral route the nutrients can reach the bowel lumen where enterocytes draw upon their fuel, preserving the barrier effect and modulating the cytokine response. Parenteral supply does not achieve this target since the blood supply of nutrients is not as important as the luminal supply. It is only via the enteral supply route that we can preserve the barrier effect. Since the cytokine response sets in immediately after a trauma such as surgery, we implement uninterrupted enteral nutrition, which means before, during and after surgery, plus parenteral support till the full calorie intake is achieved. In a hepatic resection study, we have demonstrated that enteral nutrition modulates the interleukin-6 immunological response and shortens both the period to bowel movement resumption and the duration of hospital stay. Aggressive enteral nutrition has also been implemented in severe pancreatitis, allowing control of the disease without the onset of septic complications. The most important target is not to achieve full calorie intake rapidly, but to supply the enteric mucosa continuously with useful immuno-nutrients, such as glutamine and fibres, to preserve the barrier effect, the mucus layer, and immunological status of the mucosa. In this way we have obtained significant results in the surgical treatment of these patients, reducing the infection rate and hospital stay. New prospects may be,possible in the fight against surgical infections by adding probiotics to enteral nutrition in order to improve the microenvironment of the colon.     

Circumferential tracheal reconstruction for the functional treatment of airway compromise

OBJECTIVES/HYPOTHESIS: The objective was to describe a surgical technique for replacement of long tracheal defects with a totally autologous free prefabricated cutaneous chondromucosal forearm tubular flap, applied to humans. STUDY DESIGN: Surgical reconstruction of the trachea. METHODS: A three-stage surgery was performed in a 25-year-old patient who presented with a long tracheal defect not resolved by previous resection with primary anastomosis and laser surgery. RESULTS: The staged surgery has been well tolerated by the patient, and no problems at all were reported. The postoperative computed tomography scan and the bronchofibroscopy examination of the "neo-trachea" at 2 and 6 months revealed normal caliber, good healing of the suture lines, absence of crusts or granulation tissue, and a well-vascularized internal mucosal lining. CONCLUSION: The modified flap reconstruction technique has the potential to be considered reliable for the definitive circumferential reconstruction of extensive laryngotracheal defects not amenable to being cured by conventional techniques.