[Lung transplantation in cystic fibrosis: perioperative mortality]

OBJECTIVE

To determine the incidence and causes of perioperative mortality following lung transplant for cystic fibrosis.

PATIENTS AND METHODS

We analyzed the cases of 57 patients. Fifty-five patients received double lung transplants, 1 received a heart-double lung transplant, and 1 received a combined double lung and liver transplant. Information related to the organ donor, recipient, lung graft, and early postoperative period was gathered. Perioperative mortality was defined as death resulting from anesthesia or surgery regardless of how many days had passed. The Kaplan-Meier method was used to analyze survival. A Cox logistic regression model was used to determine variables affecting mortality.

RESULTS

Survival was 83.7% at 1 year after transplantation, 77.3% at 2 years, and 66.9% at 5 years. Five (8.7%) patients died as a result of anesthesia or surgery. A ratio of PaO2 to inspired oxygen fraction (FiO2) less than 200 mm Hg in the early postoperative period was observed in 8 (14%) patients. Primary graft failure occurred in 4 patients, due to pneumonia in 2 and to biventricular dysfunction in 2. Three of those patients died. Two patients with PaO2/FiO2 greater than 200 mm Hg died after surgery, one from septic shock due to Pseudomonas cepacia and the other from massive cerebral infarction. PaO2/FiO2 upon admission to the recovery care unit was the only variable significantly associated with perioperative mortality in the logistic regression model (P=.0034).

CONCLUSIONS

The only factor significantly related to perioperative mortality in patients receiving transplants for cystic fibrosis was PaO2/FiO2 upon admission to the recovery unit.

Assessment of a platelet function analyser in horses: reference range and influence of a platelet aggregation inhibitor

The objective of this study was to assess whether a new human platelet function analyser (the PFA-100) could be used to evaluate platelet function in horses and detect acetylsalicylic acid (ASA)-induced platelet dysfunctions. Citrated blood samples from 40 healthy horses were processed to obtain reference values for closure time (CT) using cartridges with collagen-ADP (CT-ADP) and collagen-epinephrine (CT-EPI) as platelet agonists. In addition, CT-ADP and CT-EPI were also measured before and 24 h after oral ASA administration in another 12 healthy horses. The sensitivity and specificity of the test were also determined. In normal horses, means+/-SD value for CT-ADP was 85.1+/-13.1 s (median, 82 s), and CT-EPI ranged from 158 to >300 s (median 291 s). Calculated reference ranges were 60.5-115.9 s and 158.5->300 s for CT-ADP and CT-EPI, respectively. Administration of ASA significantly (P<0.001) prolonged CT-ADP values from 91.0+/-13 to 113.5+/-14.4 s, and CT-EPI values were also significantly (P<0.008) prolonged after ASA administration. Sensitivity and specificity results for ADP cartridges showed that a prolonged CT value would be highly suggestive of a platelet aggregation inhibition. In conclusion, ADP cartridges can be used in horses to assess primary haemostasis and may be a valuable test for the detection of platelet aggregation inhibition.

[T2N1M0 non-small cell lung cancer: surgery and prognostic factors]

OBJECTIVE

To determine the prognostic factors for the survival in a group of patients operated on for a non-small cell lung cancer classified as T2N1M0.

PATIENTS AND METHODS

Two hundred sixteen patients treated exclusively with surgery were studied. Kaplan-Meier survival and Cox multivariable regression analyses were used.

RESULTS

The overall survival rate was 39.8% at 5 years and 29.9% at 10 years. Sex, age, presence or absence of symptoms, type of resection, number, and location of affected lymph nodes had no effect on survival. Tumor size (P=.04) and histologic type (P=.03) did significantly affect prognosis. Both variables entered into the Cox multivariable regression model.

CONCLUSIONS

Patients operated on for non-small cell lung cancer classified as T2N1M0 have an overall probability of 5-year survival of approximately 40%. However, the prognosis for this group of patients is heterogeneous: in our study it was affected by the histologic type (45.5% for squamous cell and 25% for non-squamous cell cancers) and tumor size (53% for tumors with a diameter of <or=3 cm, 45% for tumors between 3.1 and 5 cm, and 29% for a tumor diameter >5 cm).

[Pharmacoresistant temporal-lobe epilepsy. Exploration with foramen ovale electrodes and surgical outcomes]

AIM

To report our experience in the surgical treatment of temporal-lobe epilepsy.

PATIENTS AND METHODS

An analysis was performed of the outcomes of 137 patients submitted to surgery between 1990 and 2001, with a follow-up of more than two years. A study was conducted of the percentages of successful detection by the different complementary tests--MRI, EEG, interictal SPECT, video-EEG with foramen ovale electrodes (FOE), neuropsychological study (NPS)--and the precision with which they reported the epileptogenic focus.

RESULTS AND CONCLUSIONS

Successful surgical outcomes (Engel grades I-II): 73.4%. No surgical mortality occurred, although some mild, reversible morbidity was observed. Surgical outcomes were not affected by sex, age, age of onset and the length of time the patient had had the disease, or the frequency of the seizures. No association was found between seizures in the immediate post-operative period and a poorer long term control of the epilepsy. MR images were normal in 25% of patients; in these cases the surgical outcomes (Engel grades I-II at two years: 62%) were significantly poorer than in cases of tumours/cavernomas (86%); RMI studies of other types of lesions gave intermediate results (72%). With respect to the capacity of the different tests to lateralise/locate the epileptogenic focus, video-EEG-FOE proved to be the best, followed by MRI, SPECT, EEG and NPS.

[Non-small cell bronchogenic cancer in stage IA: mortality patterns after surgery]

OBJECTIVE

To determine the causes of death in patients treated surgically for nonsmall cell lung cancer (NSCLC) in stage IA and to evaluate the impact on survival of not performing systematic lymph node dissection and of the number of nodes resected.

PATIENTS AND METHODS

The study sample consisted of 156 patients operated on for NSCLC and classified in stage IA according to TNM staging. Only palpable or visible lymph nodes were dissected. Kaplan-Meier survival curves were compared using a log-rank test.

RESULTS

At the end of the study, 85 (54.5%) patients had died, 67 (42.9%) were alive, and 4 (2.5%) were lost to follow up. Twenty-three (14.7%) died from a recurrence of NSCLC: 2 with local tumors (1.2%), 2 with mediastinal node involvement (1.2%), and 19 (12.1%) with distant metastasis. The cause of death was unrelated to NSCLC in 62 (39.7%) cases: 33 (21.1%) had a new tumor, 18 of which were bronchogenic, and 29 (18.5%) had nonmalignant disease. The 5-year survival rate was 81.4%. The rate was 88.9% among patients from whom no lymph nodes were excised and 79.9% among those with node excision, although the difference was not statistically significant (P=.4073).

CONCLUSIONS

Our experience suggests that neither the fact of not performing systematic lymph node dissection nor the number of nodes resected has an impact on survival. A substantial number of patients died of causes unrelated to the NSCLC for which they had been treated.

Jamming during the discharge of granular matter from a silo

In this work, we present an experimental study of the jamming that stops the free flow of grains from a silo discharging by gravity. When the outlet size is not much bigger than the beads, granular material jams the outlet of the container due to the formation of an arch. Statistical data from the number of grains fallen between consecutive jams are presented. The information that they provide can help one to understand the jamming phenomenon. As the ratio between the size of the orifice and the size of the beads is increased, the probability that an arch blocks the outlet decreases. We show here that there is a power-law divergence of the mean avalanche size for a finite critical radius. Beyond this critical radius, no jamming can occur and the flow is never stopped. The dependence of the arch formation on the shape and the material of the grains has been explored. It has been found that the material properties of the grains do not affect the arch formation probability. On the contrary, the shape of the grains deeply influences it. A simple model to interpret the results is also discussed.

Implementation of a strategy to prevent TRALI in a regional blood centre

Transfusion-related acute lung injury (TRALI) can be a life-threatening complication of transfusion and it is probably underdiagnosed. Human leucocyte antigen (HLA) and granulocyte antibodies are thought to play a major role, but preventive measures are difficult to implement. In our regional blood centre, we implemented a preventive strategy avoiding donor deferral. Previously, pregnant apheresis donors were screened for HLA antibodies, and those with positive results were assigned to a plasma-only protocol. Plasma from these donors and from all previously pregnant whole blood donors was diverted for protein fractionation. Plasma-poor red blood cells (in additive solution, buffy coat removed) and platelets (pools with additive solution) were prepared. Prestorage leucodepletion was also applied. We found HLA antibodies in 18.1% of previously pregnant apheresis donors, and our strategy caused a 6.0% loss of apheresis platelets, a 4.8% increase of apheresis fresh frozen plasma (FFP) and a 7.8% loss of transfusable apheresis FFP. The effect on FFP from whole blood donors could be compensated. The platelet preparation method reduced the mean volume of plasma from each donor to 24.4 mL. Fifteen months after the start of our strategy, no cases of TRALI have been reported. Our experience shows that a practical strategy to prevent TRALI is feasible.

Microanatomy of the dysplastic neocortex from epileptic patients

Focal cortical dysplasia (FCD) is a pathology that is characterized by the abnormal development of the neocortex. Indeed, a wide range of abnormalities in the cortical mantle have been associated with this pathology, including cytoarchitectonic alterations and the presence of dysmorphic neurons, balloon cells and ectopic neurons in the white matter. FCD is commonly associated with epilepsy, and hence we have studied the ultrastructure of cortical tissue resected from three subjects with intractable epilepsy secondary to cortical dysplasia to identify possible alterations in synaptic circuitry, using correlative light and electron microscopic methods. While the balloon cells found in this tissue do not appear to receive synaptic contacts, the ectopic neurons in the white matter were abnormally large and were surrounded by hypertrophic basket formations immunoreactive for the calcium-binding protein parvalbumin. Furthermore, these basket formations formed symmetrical (inhibitory) synapses with both the somata and the proximal portion of the dendrites of these giant ectopic neurons. A quantitative analysis revealed that in the dysplastic tissue, the density of excitatory and inhibitory synapses was different from that of the normal adjacent cortex. Both increases and decreases in synaptic density were observed, as well as changes in the proportion of excitatory and inhibitory synapses. However, we could not establish a common pattern of changes, either in the same patients or between different patients. These results suggest that cortical dysplasia leads to multiple changes in excitatory and inhibitory synaptic circuits. We discuss the possible relationship between these alterations and epilepsy, bearing in mind the possible limitations that preclude the extrapolation of the results to the whole population of epileptic patients with dysplastic neocortex.

Management of leishmanial osteolytic lesions in a hypothyroid dog by partial tarsal arthrodesis

A five-year-old male boxer, previously diagnosed with leishmaniasis and hypothyroidism, had gradually become unable to bear weight on its left hindlimb. Physical examination revealed a left popliteal lymphadenopathy, mild crepitus, and severe swelling of the left tarsal joint, a radiographic examination of which revealed severe bone destruction of the talus and a periosteal reaction of the calcaneus. Laboratory findings and serological tests suggested an active leishmanial infection, and a Leishmania species was identified by direct cytology of a sample from the osteolytic area and by indirect immunohistochemistry of a bone biopsy. The dog's condition improved when it was treated with meglumine antimonate and allopurinol. Because of the large osteolytic area and the increased use of the affected leg, a partial tarsal arthrodesis was performed to prevent a fracture. Five months after the surgery, the osteolytic area had healed completely and the calcaneus periosteal reaction had disappeared.

Comparative haematology and chemistry of endangered lizards (Gallotia species) in the Canary Islands

Blood samples were taken from the ventral coccygeal vein of 15 El Hierro giant lizards (Gallotia simonyi) (seven females and eight males), six La Gomera giant lizards (Gallotia bravoana) (four males and two females) and four Tenerife giant lizards (Gallotia intermedia) (two males and two females), and 31 blood parameters were measured. Among the haematological parameters there were significant differences between the three species in heterophils, azurophils and lymphocytes, but no significant differences in red blood cell count, white blood cell count, haemoglobin, packed-cell volume, monocytes, eosinophils and basophils. In terms of blood chemistry there were significant differences between the three species in cholesterol, triglycerides, glucose, sodium, chloride, urea, uric acid, total proteins, prealbumin, albumin and gamma globulins, but no significant differences in calcium, potassium, aspartate aminotransferase, alanine aminotransferase, creatine kinase, bile acids, alpha-1 and alpha-2 globulins and beta globulins.

[The natural history of sperm cleareance after vasectomy]

OBJECTIVE

To study the time required to obtain a negative sperm analysis after vasectomy.

MATERIAL AND METHODS

We reviewed 239 consecutive vasectomies performed between september 1998 and september 1999. All of them were done in an ambulatory basis. Follow up interval was 41-853 days (mean 144, median 104). The first semen analysis was requested between 1 and 6 months after the surgical procedure. If the sample still showed spermatozoa, then a new one was requested every two months. Probability of becoming azoospermic was studied with Kaplan-Meier curves.

RESULTS

Persistent spermatozoa could be found in 31 patients (13%) at the end of follow-up. Despite having a positive semen analysis, 10 patients (4.2%) discontinued medical visits. Time required to obtain a negative sperm count ranged from 58 to 362 days (mean 133, median 99). The probability of being azoospermic 200 and 260 days after vasectomy was 80-90% respectively. A total of 328 semen analysis were requested (range 1-4, mean 1.37, median 1)

CONCLUSIONS

A minimum of 200 days (6.6 months) are needed to clear all the spermatozoa in semen after vasectomy in 80% of our patients. Requesting the first semen sample 7 months after vasectomy is cost-effective, reducing unnecesary medical visits and increasing the rentability of this test.

[Stage I nonsmall cell lung cancer up to 3 cm in diameter. Prognostic factors]

OBJECTIVE

To assess the prognostic value of a series of clinicopathological variables in stage I nonsmall cell lung cancer, for tumors up to 3 cm in diameter.

PATIENTS AND METHOD

The study included 271 patients. Survival was analyzed with the Kaplan-Meier method. The Cox model was used for multivariate analysis.

RESULTS

Five- and ten-year survival were 78.63% and 67.59%, respectively. Survival did not significantly depend on sex, age, extent of resection, histology, visceral pleural invasion, level of bronchial invasion or T1 versus T2. The decade in which resection was performed did affect survival (P=.0037). Five-year survival was 58% for operations between 1970 and 1980, 77% for operations between 1981 and 1990, and 84% for operations between 1991 and 2000. Tumor size also affected survival (P=.0046), which was 86% for patients with tumors of less than or equal to 2 cm in diameter and 73% for those with tumors of more than 2 cm in diameter. In the multivariate analysis both variables entered into regression, remaining predictive of survival.

CONCLUSION

We found evidence for a prognostic stage migration (Will Rogers phenomenon) according to the decade in which resection was performed and that tumor size affected survival in our population. Finally, the current system of TNM staging fails in conforming groups of patients with a homogenous prognosis.

[Psychosurgery and the neurosurgical treatment of pain: a systematic review of the experience gained in these kinds of treatment]

INTRODUCTION

Psychosurgery and the neurochemical treatment of pain (NTP) are therapeutic options restricted to patients who show resistance to medical treatments. Surgical techniques have been perfected over the last few decades.

AIMS

Our aim was to conduct a systematic review of the studies dealing with psychosurgery and NTP reported in the literature, based on the standards of quality used in evidence-based medicine.

DEVELOPMENT

Following screening and selection, nine of the 178 papers found (MEDLINE, 1990-2002) were selected for the study: three referring to the treatment of neuropathic pain and six about the treatment of obsessive-compulsive disorder (OCD). The objectives were the therapeutic results in all cases, the study of the anatomical-functional bases in three of them and the description of side effects in five. After adapting the standards of quality used in evidence-based medicine (there are no standards for papers about surgery), one was classified in group B, six in group C and two as C-D. The three papers about the treatment of pain reported a significant improvement in the pain scales in 40-77% of patients. As regards the treatment of OCD, results showed an overall improvement of the scales in 20.4-70% of the patients with an improvement above 50%. The side effects are also described.

CONCLUSIONS

Data published support the indication of psychosurgery and NTP for selected patients with neuropathic pain and OCD. The methodological limitations of the papers prevent us from drawing conclusions about the other diseases for which these techniques have been indicated.

[Treatment of a case of essential tremor with subthalamic stimulation]

INTRODUCTION

Chronic stimulation of the subthalamic nucleus (STN) has proved itself to be useful in treating Parkinson's disease and especially in dealing with the tremor suffered by patients. Yet there is very little experience to support the use of STN as an alternative therapy in non Parkinsonian tremors.

CASE REPORT

Our study considered the case of a patient who had been diagnosed as suffering from drug resistant essential tremor which was predominant in the distal region of the upper right limb and was treated by unilateral stimulation of the STN.

RESULTS

The patient's clinical state improved significantly from the first weeks onwards. After a year and a half of therapy, the patient had achieved a stable improvement of 82.4% on the tremor scale and medication was reduced by 41.7%.

CONCLUSIONS

SNT stimulation appears as a suitable target for the treatment of drug resistant essential tremor.

[Voltage sources analysis in studies with foramen ovale electrodes]

INTRODUCTION

Paroxysmal activity in medial temporal lobe epilepsy is originated in either hippocampal or parahippocampal regions. This activity can be directly recorded by foramen ovale electrodes. That paroxysmal activity will start from irritative or ictal areas. However, anatomo-functional relations between both regions are still debated.

OBJECTIVE

We describe a new physical very simple model which allows to directly analysis the anatomo-physiological relations between sources for interictal and ictal areas.

RESULTS

1) The mathematical model allows to fit with minimum error and great precision the voltage sources originated from monopoles. 2) We can obtain this degree of precision with a matrix using an internodal distance of 0.1 mm (300x200 nodes) 3) Triplets of potentials with double sources with equal or specially with inverse charges have bigger error than monopolar charges. 4) Fitting real data obtained from a patient shows an error of 0.29 +/- 0.17% for interictal and 0.54 +/- 1.22% and 2.84 +/- 3.00% for two seizures (mean +/- SD).

CONCLUSIONS

This model allows directly to know the relative anatomo-physiological relations between interictal and ictal sources in MTLE, which have a very important implications so for patho-physiological as therapeutics and outcome implications.