Evacuación aeromédica de pacientes COVID-19. Reporte de casos / Case reports: Aeromedical evacuation of patients COVID-19

BACKGROUND: The aeromedical evacuation in the Chilean Air Force has had an important development in the last 15 years. The coronavirus disease declared as a global pandemic by the WHO has generated the challenge of transferring highly infectious patients to centers of greater complexity. The objective of this article is to report our experience in the transfer of COVID ­ 19 patients in constant attention and medical monitoring. CLINICAL CASE REPORTS: The aeromedical evacuation of 2 COVID-19 patients was performed from the Hanga Roa Hospital, Rapa Nui, to the National Thorax Institute, Metropolitan Region, in a Lockheed Hercules C-130, which corresponds to a pressurized fixed-wing airplane. The transfer was carried out with the corresponding personal protection elements and in individual isolation capsules with advanced negative pressure life support (ISO ­ POD), in order to reduce the level of contagion to the aero sanitary crew and minimize the impact on the flight material used. DISCUSSION: The transfer was carried out achieving all the objectives set out under a strict security protocol and the two COVID-19 patients were transferred successfully. The negative pressure isolation capsule system was safe and reliable, since no crew member presented symptoms or was infected by COVID -19, and also allowed the transfer of highly contagious patients during an 8-hour flight operation.

INTRODUCCIÓN: La evacuación aeromédica en la Fuerza Aérea de Chile ha tenido un importante desarrollo en los últimos 15 años. La enfermedad por coronavirus declarada como pandemia mundial por la OMS ha generado el desafío de trasladar pacientes altamente infecciosos a centros de mayor complejidad. El objetivo de este artículo es reportar nuestra experiencia en el traslado de pacientes COVID ­ 19 en constante atención y monitorización médica. REPORTE DE CASOS CLÍNICOS: Se realizó la evacuación aeromédica de 2 pacientes COVID ­ 19 desde el Hospital de Hanga Roa, Rapa Nui, hacía el Instituto Nacional del Tórax, Región Metropolitana, en un Lockheed Hércules C-130, que corresponde a un avión de ala fija presurizado. El traslado se realizó con los elementos de protección personal correspondientes y en capsulas de aislamiento individual con soporte vital avanzado a presión negativa (ISO ­ POD), con la finalidad de reducir el nivel de contagio a la tripulación aero sanitaria y minimizar el impacto en el material de vuelo utilizado. DISCUSIÓN: El traslado se desarrolló logrando todos los objetivos planteados bajo un estricto protocolo de seguridad y los dos enfermos COVID-19 fueron trasladados de manera exitosa. El sistema de cápsulas de aislamiento a presión negativa fue seguro y confiable, ya que ningún miembro de la tripulación presento sintomatología o resultó contagiado por COVID -19, y además permitió trasladar pacientes altamente contagiosos durante una operación de vuelo de 8 horas.

Complicaciones de la pancreatoduodenectomía, diagnóstico y manejo / Diagnosis and management of pancreatoduodenectomy complications

Pancreatoduodenectomy continues to have a high rate of complications. The most common and severe complications are intra or postoperative bleeding, pancreatic fistulae and derangements of gastric emptying. Each of these requires a great deal of clinical suspicion and an multidisciplinary management. This is a review of these complications, their clinical manifestations and their management.

A pesar de la disminución observada en las cifras de mortalidad de la pancreatoduodenectomía, continúa siendo una intervención asociada a una alta tasa de complicaciones. Las más comunes y asociadas a una mayor morbimortalidad son: el sangrado intra y post operatorio, la fístula pancreática y trastornos asociados al vaciamiento gástrico. Cada una de los eventos anteriores, requiere de un alto grado de sospecha clínica y de un manejo de tipo multidisciplinario. En este reporte se analizan las complicaciones anteriormente descritas, sus manifestaciones clínicas y los principios de su manejo.

Gastrectomía vertical posterior a retiro de banda gástrica / Sleeve gastrectomy performed simultaneously to extraction of a gastric band: experience in 10 patients

Background: Sleeve gastrectomy is replacing gastric banding in the management of morbid obesity. Aim: To report the results of sleeve gastrectomy performed simultaneously with the extraction of a gastric band. Material and Methods: We report ten patients aged 34 to 53 years (nine women) operated between 2008 and 2009. Results: The main indication for sleeve gastrectomy was the failure of the gastric band. No complications were recorded and patients were discharged 72 hours after the procedure. Conclusions: Sleeve gastrectomy can be carried out simultaneously with the extraction of a gastric band, without increasing operative complications.

Introducción: La Gastrectomía Vertical ha reemplazado a la banda gástrica en el manejo de un importante número de pacientes portadores de obesidad. El objetivo de este trabajo es mostrar los resultados de una serie de pacientes, en los que se realizó una Gastrectomía Vertical posterior a la extracción de una banda gástrica en un mismo tiempo operatorio. Método: La serie incluye a 10 pacientes operados entre Mayo de 2008 y Noviembre de 2009. La principal indicación de la Gastrectomía Vertical fue el fracaso de la banda como tratamiento de la obesidad. Resultados: En los 10 pacientes estudiados, la gastrectomía se pudo efectuar sin mayores dificultades ni diferencias con respecto al procedimiento habitual. No existieron complicaciones post operatorias, siendo la totalidad de los pacientes dados de alta dentro de las 72 horas. Conclusión: La Gastrectomía Vertical representa una alternativa de manejo en pacientes portadores de una banda gástrica con indicación de extracción de esta, ya sea por fracaso o por síntomas asociados a su presencia. El procedimiento puede efectuarse de manera segura en el mismo acto operatorio y sus resultados son comparables a los observados cuando la técnica se efectúa en pacientes que no han sido intervenidos previamente.

Colesterolosis y cáncer de la vesícula biliar / Association between cholesterolosis and gallbladder cancer

Background: Cholesterolosis is frequently observed in cholecystectomies performed for lithiasis or chronic cholecystitis. Aim: To determine the degree of association between cholesterolosis and gallbladder cancer. Material and Methods: In a prospective study of gallbladder cancer, all gallbladders obtained during cholecystectomies were processed for pathological study, following a special protocol. As part of this study, 23304 surgical samples obtained between 1993 and 2002 were studied, looking for a relationship between cholesterolosis and chronic cholecystitis, adenomas, dysplasia and gallbladder cancer. Results: Seventy nine percent of patients were women. Cholesterolosis was observed in 3,123 cases (13.4 percent). Cholesterolosis was more common in women (14.2 percent) than in men (10.2 percent) (p < 0.001). In the same period, 29 patients were diagnosed with adenomas (0.12 percent), 179 cases with dysplasia not associated with gallbladder cancer (0.8 percent) and 739 gallbladder cancer (3.2 percent). The frequency of cholesterolosis was 13.8 percent in chronic cholecystitis, 13.7 percent in adenomas, 12.1 percent in dysplasias and 1.35 percent in patients with gallbladder cancer (p < 0.01). Of the thirteen cases with gallbladder cancer and cholesterolosis, 10 were early gallbladder carcinomas. Patients with cholesterolosis were 9.2 times less likely to have cancer than those who did not have cholesterolosis. Conclusions: Cholesterolosis has a strong negative association with gallbladder cancer.

[p53 and p27 gene expression in subserosal gallbladder carcinoma]. / Carcinoma subseroso de la vesícula biliar (pT2): valor pronóstico de la expresión de los genes supresores de tumores p53 y p27 en matrices de tejidos.

BACKGROUND: Subserosal carcinoma is the stage that presents the greatest difficulty in the diagnosis therapeutic handling and prognosis evaluation. AIM: To study the expression of p53 and p27 genes in subserosal gallbladder cancer. MATERIAL AND METHODS: One hundred twenty seven tissue samples of subserosal gallbladder cancer (coming from 112 females aged 62+/-13 years and 15 men aged 67+/-17 years) and 50 control samples were selected to construct tissue arrays. p53 and p27 genes were determined by immunohistochemistry. RESULTS: Thirty eight percent of tumors were not detected at the macroscopic examination, 52% and 17% had lymph node and blood vessel involvement, respectively. Fifty six and 46% were positive for p53 and p27, respectively. No association between the expression of both genes and gender, degree of differentiation, lymph node or blood vessel involvement, was observed. Overall five years actuarial survival was 32%. Patients with positive or negative p53 expression had a 22% and 53% survival, respectively (p=0.05). No association between survival and p27 expression was observed. CONCLUSIONS: p53 gene expression is a prognostic factor for subserosal gallbladder cancer.

Carcinoma subseroso de la vesícula biliar (pT2): valor pronóstico de la expresión de los genes supresores de tumores p53 y p27 en matrices de tejidos / p53 and p27 gene expression in subserosal gallbladder carcinoma

Background: Subserosal carcinoma is the stage that presents the greatest difficulty in the diagnosis therapeutic handling and prognosis evaluation. Aim To study the expression of p53 and p27 genes in subserosal gallbladder cancer. Material and methods: One hundred twenty seven tissue samples of subserosal gallbladder cancer (coming from 112 females aged 62 ± 13years and 15 men aged 67 ± 17years) and 50 control samples were selected to construct tissue arrays. p53 andp27genes were determined by immunohistochemistry. Results: Thirty eight percent of tumors were not detected at the macroscopic examination, 52 percent and 17 percent had lymph node and blood vessel involvement, respectively. Fifty six and 46 percent were positive for p53 and p27, respectively. No association between the expression of both genes and gender, degree of differentiation, lymph node or blood vessel involvement, was observed. Overall five years actuarial survival was 32 percent. Patients with positive or negative p53 expression had a 22 percent and 53 percent survival, respectively (p =0.05). No association between survival and p27 expression was observed. Conclusions: p53 gene expression is a prognostic factor for subserosal gallbladder cancer.

Desde la displasia hasta el cáncer de la vesícula biliar / Natural history of gallbladder cancer Analysis of biopsy specimens

Background: There is scarcity of knowledge about the development of gallbladder cancer. Aim: To study the features of development and progression of gallbladder cancer. Material and methods: Review of histopathological studies of gallbladder obtained in 25,971 cholecytectomies performed in patients aged 45± 16 years, 79 percent females, between 1993 and 2004. Among these, 210 had a dysplasia not associated to cancer and 1,039 had a gallbladder cancer Clinical and morphological parameters of preneoplastic and neoplastic lesions were analyzed. Ninety five percent of patients were followed. Results: All cases of dysplasia were incidental findings. Metaplasia, dysplasia and carcinoma in situ were present in the adjacent mucosa in 66 percent, 81 percent y 69 percent of gallbladder carcinomas, respectively. Twenty five percent of gallbladders studied were carcinomas (mucous carcinoma in 18 percent and muscular carcinoma in 7 percent). Ninety two percent of cases had chronic inflammation in the gallbladder wall. Seventy two percent of mucous carcinomas were not detected macroscopically Five years survival of mucous carcinoma was 92 percent. There was an association between the intensity of the lesion and the age of the patients. The age difference between chronic cholecystitis and gallbladder cancer was 11 years for women and nine for men. Conclusions: From a morphological standpoint, the period in which a dysplasia becomes a carcinoma is approximately 10 years.

Proliferación celular en la mucosa de la vesícula biliar no tumoral en colecistitis crónicas litiásicas. Expresión de Ki-67 en matrices de tejidos / Immunohistochemical expression of Ki-67 as a marker of proliferation in gallbladder mucosa samples with or without cancer

Background: There is paucity of knowledge on the proliferative features of normal or chronically inflamed gallbladder and the mechanisms of development of gallbladder cancer. Aim: To study the proliferation features of non tumoral gallbladder mucosa through the expression of Ki-67 antigen in tissue micro array analysis. Material and methods: The immunohystochemical expression of Ki-67 in tissue micro array was studied in 96 samples of non tumoral gallbladder mucosa (coming from 74 females aged 45±16 years and 22 males aged 53±16 years) and 102 samples of gallbladder cancer (coming from 84 females aged 62± 14 years and 18 males aged 70± 13 years). Results: The staining index of Ki-67 expression was 19±25 percent (range 096-8996) in samples of non tumoral mucosa and 46±29 percent (range 396-9896) in gallbladder cancer (p <0.01). Ki-67 was expressed in less than 10 percent of epithelial cells in 55 percent of non tumoral mucosa samples and 6 percent of gallbladder cancer samples. Seventy five percent of gallbladder cancer samples had a staining index of more than 20 percent. An expression of Ki-67 over 20 percent or 50 percent was observed in 25 percent and 15 percent of non tumoral mucosa samples, respectively Conclusions: Non tumoral gallbladder mucosa samples have a high proliferation index, measured using Ki-67 immunohystochemical expression. There is a group of samples with cellular hyper-proliferation that maybe related to the pathogenesis of gallbladder cancer.

[Detection of gastric preneoplastic lesions with serum levels of pepsinogen in Chilean subjects]. / Detección de lesiones preneoplásicas gástricas mediante niveles séricos de pepsinógeno en población chilena.

BACKGROUND: Gastric cancer has a direct relation with chronic atrophic gastritis (AG) and intestinal metaplasia (IM), considered as preneoplastic lesions. Determination of serum pepsinogen llevéis (PGI) and pepsinogen I / pepsinogen II ratio (PGI/PGII) can detect this conditions; achieving 70-90% of gastric cancer detection in early stages. AIM: To determine the cut-off values for serum PGI and PGI/PGII in Chilean subjects, for the detection of gastric preneoplastic lesions, establishing their sensitivity, specificity, positive (PPV) and negative (NPV) predictive values. PATIENTS AND METHODS: Prospective study of patients subjected to upper gastrointestinal endoscopy and determination of serum pepsinogen levels. The presence and severity of preneoplastic lesions were compared with serum levels of PGI and PGI/PGII. RESULTS: A total of 56 men and 44 women were studied, with a mean age of 43 (14-77) years. There was a significant association (p <0.001) of PGI and PGI/PGII with AG and IM. We obtained a cut-off value of 2.3 for PGI/PGII (sensitivity =70%>, specificity =92%>, PPV =60%>, NPV =95%) and 36 ng/ml for PGI (sensitivity =62%o specificity =64%o, PPV =20%o, NPV =91%), for detection of moderate to severe AG. No patient with normal mucosa had a PGI <20 ng/ml. The combined criteria of PGI/II < or = 2.3 and/or PGI < or 20 ng/ml, obtained a sensitivity of 85%o, specificity of 92%>, PPV of 65%o, and NPV of 97%o. CONCLUSIONS: We confirmed a strict relation ofPGIand PGI/PGIIwith the presence of preneoplastic gastric lesions in Chilean patients.

Mutación del gen K-ras en tumores pancreático-biliares / Frequency of K-ras mutation in biliary and pancreatic tumors

Background: The ras gene family (H-ras, N-ras and K-ras) are oncogenes that mutate frequently in human cancer, specially in tumors of the biliary tract and pancreas. Aim: To determine the frequency of K-ras gene codon 12 mutation in pancreatic and biliary tumors. Material and Methods: Samples of 35 gallbladder, 15 ampulla of Vater, 10 biliary tract and 9 pancreatic tumors, were analyzed. The tumor tissue was microdissected from paraffin embedded biopsies. The mutation was detected by a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results: Overall, 46% of samples had K-ras gene mutations. Mutation frequency was 80, 56, 50 and 29% for ampulla of Vater, pancreatic, biliary tract and gallbladder tumors, respectively. When compared with the rest, gallbladder tumors had a significantly lower frequency of the mutation. Median survival for biliary tract tumors was 6 months, compared with 65 months for gallbladder tumors (p <0.05). Conclusions: Gallbladder carcinoma had the lower frequency of K-ras mutation, when compared with pancreatic, biliary tract and ampulla of Vater tumors.

Detección de micrometástasis en médula ósea de pacientes con cáncer de vesícula biliar / Detection of bone marrow micrometastases in patients with gallbladder cancer

Background: There is a very strong documented correlation between the appearance of cancer cells in blood and occurrence of metastasis in gastrointestinal cancer. Aim: To determine MUC1, CK19, CK20 and CEA mRNA expression in bone marrow of patients with gallbladder cancer and evaluate its clinical significance. Material and methods: Sixty eight samples were analyzed, 38 bone marrow samples of gallbladder cancer patients, 20 healthy donors, and 10 frozen samples of gallbladder cancer. Nested reverse transcriptase-polymerase chain reaction (nested RT-PCR) was used to analyze mRNA expression. Results: All frozen tumors were positive for CEA, CK19, and MUC1 mRNA and 70 percent were positive for CK20. Seventeen of 20 donor samples were positive for MUC1 and only one sample from donors was positive for both CK20 and CK19 mRNA. Among the 38 blood and bone marrow samples of gallbladder cancer patients, the expression of MUC1, CK19, CK20, and CEA, mRNA was 60.5 percent (23/38), 31.6 percent (12/38), 7.9 percent (3/38), and 7.9 percent (3/38), respectively. Disregarding the MUC1 results. 37 percent (14/38), 13 percent (5/38) and 5 percent (2/38) were positive for one, two and three markers respectively. Not significant differences were found in survival with a follow up to 12 months. Conclusion: Our results indicate that the molecular detection of tumor cells in bone marrow in patients with gallbladder carcinoma is technically possible, being CEA, CK19 and CK20 gene expression the best markers. The MUC1 gene expression marker was highly unspecific and it should not been considered. The detection of bone marrow micrometastasis might be helpful in prognosis and the selection of clinical treatment but a larger series with a longer follow-up should be studied.

Inactivación del gen CDKN2A (p16) en cáncer de la vesícula biliar / Inactivation of CDKN2A gene (p16) in gallbladder carcinoma

Background: The CDKN2A gene encodes a cyclin dependent kinase inhibitor, p16, which promotes cell cycle arrest. Methylation of the promoter region trans-criptionally inactivates the gene. Aim: To study the relationship between methylation status of the prometer region of p16 gene, the immunohistochemical expression of p16 and clinical and morphological features of gallbladder carcinoma. Material and methods: We analyzed the methylation status of the promoter region of the CDKN2A gene in gallbladder adenocarcinomas using methylation specific PCR (MSP). We also used microsatellite markers near the CDKN2A gene to detect allelic imbalance (AI) and examined the tumors by immunohistochemistry (IHC) for p16 expression. Results: Of 38 gallbladder adenocarcinomas analyzed by IHC, 11 cases (29%) were negative for p16 protein. Nine (24%) had methylation of the promoter region of the CDKN2A gene. Twenty nine cases were negative for methylation, but four (14%) of these 29 exhibited AI at one or more of the microsatellite markers. CDKN2A promoter methylation was not associated with microsatellite instability (MSI-H). Conclusions: The inactivation of CDKN2A by methylation and/or deletion might play an important role in gallbladder carcinogenesis.

Cáncer de la vesícula biliar: manejo de pacientes con invasión de la túnica muscular / Management of gallbladder cancer with invasion of the muscular layer

Background: Gallbladder cancer is the leading cause of death of cancer among women in Chile. Detection of early forms of the disease during the pathological study of the cholecystectomy specimen is common. The management of these cases, specially those with invasion of the muscular layer is under discussion. Aim: To analyze the clinical features of patients with gallbladder cancer and muscular layer invasion and their prognosis after a simple cholecystectomy. Patients and methods: We studied a series of 46 patients with gallbladder cancer and invasion of the muscular layer. In the majority of cases diagnosis was performed at the moment of specimen study. Eleven patients underwent reoperation. Of these, ten underwent lymphadenectomy and liver resection while one patient underwent resection of the cystic duct stump. Results: During follow up, five patients died as a consequence of gallbladder cancer. Overall survival was 78 percent, with no differences between patients subjected or not a new operation. Conclusions: Gallbladder cancer with muscular infiltration has a good prognosis, independent of the type of therapy.

Cancer de vesícula biliar en la IX región de Chile: impacto del estudio anatomopatológico en 474 casos / Gallbladder cancer in the IX region of Chile: importance of anatomopathological study in 474 cases

We studied prospectively 474 cases (83 percent female with a female: male ratio of 5:1) of gallbladder carcinoma diagnosed in a period of 7 years. 22 percent of patients were younger than 50 years old. Ninety percent of tumors were adenocarcinomas in 1987, 45 percent of cases were diagnosed in metastases compared to 1993, when only 10 percent of tumors were diagnosed in such histological material. Thirty four percent of tumors were not macroscopically identified; all these inapparent tumors were advanced in 1987, whereas 53 percent were incipient in 1993. Moreover, inapparent tumors had a significantly lower degree of gallbladder wall infiltration and higher degree of differentiation. Well differentiated tumors had a lesser degree of wall infiltration. It is concluded that the careful histopathological study of gallbladder cancer has allowed a thorough knowledge of the natural history and clinical presentation of gallbladder carcinoma

Cáncer de la vesícula biliar: evaluación prospectiva de 100 casos potencialmente curativos / Gallblader cancer: prospective evaluation of 110 cases potentially curables

Se analizan en forma prospectiva 100 pacientes portadores de un cáncer de la vesícula potencialmente curativo. De los pacientes, 17 tenían una infiltración localizada a la mucosa, 12 a la muscular, 41 a la subserosa, 12 al tejido adiposo y 18 tenían invasión de la serosa. El diagnóstico fue sospechado en el preoperatorio en sólo 5 pacientes. Los pacientes con invasión de sólo la túnica mucosa fueron solamente seguidos luego de la colecistectomía. En los restantes casos, se les ofreció a los pacientes la posibilidad de efectuar una segunda operación consistente en la resección del lecho de la vesícula biliar y una linfadenectomía del pedículo hepático. Del total de pacientes, 54 fueron reintervenidos de los cuales 41 pudiendo ser resecados. En general, los pacientes reintervenidos tuvieron una mejor sobrevida, aun cuando esta diferencia no fue observada cuando los pacientes fueron agrupados de acuerdo al nivel de infiltración en la pared. Por otro lado, la única diferencia importante fue observada entre los pacientes en quienes se efectuó cirugía curativa y aquéllos no reoperados cuando la infiltración fue limitada a la subserosa. Los resultados de este estudio indican que la reintervención en pacientes con tumores potencialmente curativos puede ser de utilidad. Sin embargo, deben hacerse esfuerzos para aumentar el diagnóstico preoperatorio y aplicar otras formas terapéuticas

La colecistectomía laparoscópica dificulta el análisis de la mucosa vesicular: estudio morfométrico / Laparoscopic cholecystectomy hampers the gallbladder mucosa analysis: morphometric study

Laparoscopic gallbladder surgery damages gallbladder mucosa, impeding an adequate histological examination. We studied gallbladder samples coming from 56 conventional and 44 laparoscopic cholecystecxtomies performed in patients with chronic cholecystitis without signs of acute inflammation. The length of each examined sample and the length of the portion where superficial epithelia was not found was measured. No differences in sample length was found between both types of cholecystectomy. However, the segment with superficila mucosa was significantly shorter in the samples coming from laparoscopic surgery. Seventeen samples did not contain mucosa at all and 14 of these (82 percent) came from laparoscopic procedures. 86 percent of samples coming from laparoscopic surgery were considered inadequate for histological study compared to 36 percent of samples coming from conventional cholecystectomy. It is concluded that laparoscopic cholecystectomy hampers the study of gallbladder mucosa and may have an impact on the diagnosis of neoplastic gallbladder lesions

Carcinoma de la vesícula biliar: expresión de productos de los oncogenes C-MYC y RAS-P-21 / Carcinoma of gallblader: expression of products of C-MYC and RAS-P-21 oncogene

The expression of c-myc and p-ras-21 oncogenes was studied using an immunohistochemical method with monoclonal antibodies in 126 samples of gallbladder carcinoma (103 primary tumors and 23 metastatic lesions). Twenty five gallbladder samples without tumor evidence were used as controls. C-myc oncoprotein was positive in one control sample and p-ras-21 oncoprotein was negative in all. Among primary carcinomas c-myc was positive in 9 (9 per cent) and 4 (4 per cent); among metastatic carcinomas c-myc was positive in 6 (26 per cent, p=0.03 vs primary carcinoma) and p-ras-21 in 11 (48 per cent, p <0.001 vs primary carcinoma). There was a non significant association between c-myc and p-ras-21 expression and degree of histological differentiation and levelñ of tumoral infiltration. It is concliuded that c-myc and p-ras-21 oncoprotein expression is observed in less than 10 per cent of primary gallbladder carcinomas and that this expression is significantly higher in metastatic cells