Granulation tissue formation -The effect of hydroxyapatite coating of cellulose on cellular differentiation

Haavan jyväiskudoksen muodostuminen – Hydroksiapatiittipinnoi-tetun selluloosasienen vaikutus solujen erilaistumiseen paranemisprosessin aikana Etsittäessä uusia luun bioyhteensopivia täytemateriaaleja selluloosasieni päällystettiin luun koostumusta muistuttavalla runsaasti piitä sisältävällä hydroksiapatiittikerroksella. Vastoin odotuksia hydroksiapatiittipinnoitettu selluloosa ei parantanut luun kasvua, vaan päinvastoin ylläpiti tulehdusta ja sidekudossolujen hakeutumista vamma-alueelle. Ihon alle implantoituna sama sienimateriaali edisti merkittävästi haavan verekkään jyväiskudoksen kasvua. Tämän löydöksen perusteella hydroksiapatiittipinnoitetun selluloosasienen vaikutusta haavan soluihin paranemisprosessin aikana tutkittiin tarkemmin ja havaittiin, että tulehdussolujen lisäksi sieniin kertyi tavallista enemmän sekä hematopoieettisia että mesenkymaalisia kantasoluja. Hematopoieettiset kantasolut sijaitsevat luuytimessä lähellä luun sisäpintaa. Luun hydroksiapatiitista vapautuu kalsiumioneja luun jatkuvan fysiologisen uudismuodostuksen ja hajottamisen yhteydessä. Kantasolut etsiytyvät luuytimeen kalsiumia aistivien reseptorien välityksellä. Koska luun pintakerrosta muistuttavasta hydroksiapatiittipinnoitteesta vapautuu kalsiumia, tämän ajateltiin toimivan selityksenä sille, että hematopoieettiset kantasolut hakeutuvat runsaslukuisesti juuri hydroksiapatiittipinnoitettuihin selluloosasieniin. Tämän hypoteesin mukaisesti hydroksiapatiittipinnoitettujen selluloosapalkkien läheisyydestä löydettiin suuria määriä kalsiumreseptoreja sisältäviä soluja. Jatkotutkimuksissa todettiin lisäksi, että hematopoieettiset kantasolut pystyivät sienissä erilaistumaan hemoglobiinia tuottaviksi soluiksi. Havaittujen punasolulinjan merkkiaineiden perusteella näyttäisikin siltä, että haavan paranemiskudoksessa tapahtuu paranemisen aikana ekstramedullaarista erytropoieesia. Nämä soluja ohjaavat vaikutukset saattavat olla hyödyllisiä vaikeasti paranevien haavojen hoidossa.Cellulose was coated with a silica-rich hydroxyapatite layer resembling the mineral composition of bone in search for a possible bone filler material. The hydroxyapatite-coated cellulose did not, however, promote bone repair but instead favored inflammation and fibroplasia. When implanted subcutaneously, these sponges rapidly generated a highly vascular granulation tissue. Further investigation revealed that hydroxyapatite-coated cellulose attracted not only inflammatory cells but also stem cells of both hematopoietic and mesenchymal origin. In the bone marrow, the hematopoietic stem cells reside near the endosteal surface of bone, where the calcium concentration is more than 20-fold of that observed in serum due to bone remodeling by osteoclasts. The hematopoietic stem cells are known to attach to their niche via calcium sensing receptors. The presence and release of calcium ions from the hydroxyapatite layer of the coated sponges might offer an explanation for more abundant accumulation of hematopoietic stem cells to the hydroxyapatite coated implants. Indeed, calcium sensing receptor-positive cells were found especially near the apatite-coated cellulose fibers in the implants. Further analyses indicated that the hematopoietic stem cells were able to differentiate into hemoglobin expressing cells. The presence of erythroid cell markers in the sponges suggests that granulation tissue is capable of extramedullary erythropoiesis. These cell-guiding properties of HA coated cellulose might be utilized in impaired wound healing situations.Siirretty Doriast

The accuracy of preliminary diagnoses made by paramedics - a cross-sectional comparative study

Background Clinical decision-making skills of paramedics have been emphasized because of the growing complexity of emergency medicine nursing. A preliminary diagnosis made by a paramedic has an essential role in directing the subsequent care. An accurate preliminary diagnosis improves the patient's outcome. The research in this area is relatively scarce and there are no previous studies in Finland describing the accuracy of preliminary diagnoses made by paramedics. The aim of this study was to evaluate whether paramedics are making accurate preliminary diagnoses for the patients they are transporting to hospital. In addition, the aim was to describe the variables related to an accurate preliminary diagnosis. Methods A cross-sectional comparative approach was used and conducted through a questionnaire to gather data from the paramedics. A total of 71 paramedics participated in the study and 378 patient cases were included. The paramedics were asked to describe the basic information of a case, to state their preliminary diagnosis, and give their own educational background. The accuracy of the paramedic's preliminary diagnosis was compared with the discharge diagnosis of the ED physicians retrieved from hospital's patient records. Logistic regression analysis and a binomial test were used to test the statistical significance. Results The agreement between the paramedics' preliminary diagnosis vs. hospital diagnosis was 70% (n = 261). Diagnostic accuracy varied according to the medical condition from mental diseases and intoxication (86%, p = 0,000), cerebral strokes(81%, p = 0,007)to infections (31% p = 0,029). The educational background of a bachelor-degree-level paramedic (p = 0,016, 95% Cl 1,7-139,6) and a good self-assessment value (p = 0,003, 95% Cl 1,2-2,7) were related to making a correct diagnosis. Conclusions Paramedics are able to determine preliminary diagnoses at satisfactory level. The relationship between educational background and diagnostic accuracy suggests that there is a definitive need for a specific pre-hospital nursing education.</div

Two cases of low birth weight infant survival by prehospital emergency hysterotomy

Background: During maternal cardiac arrest, emergency hysterotomy (EH) is recommended after four minutes of resuscitation, if no signs of spontaneous circulation are detected. This extreme procedure is believed to be potentially beneficial for both the mother and the infant. Both maternal and neonatal survivals seem to be associated to the time delay between the cardiac arrest and the delivery and in-hospital resuscitation location. In addition to this, gestational age is an important determinant to neonatal outcome. Case presentation: We report two emergency hysterotomies executed in an out-of-hospital location. The infants delivered by EH were low birth weight infants and born 20-23 min after maternal cardiac arrest. Both infants survived and had normal physical and neurological growth at the age of two years. Unfortunately, mothers in these both cases died in the field. Conclusion: Contrary to earlier beliefs, it is possible to perform a successful EH also in out-of-hospital setting, even with incomplete surgical skills. However, training and preparation are extremely important for achieving the highest possible readiness to treat maternal cardiac arrest situations also prehospitally.Peer reviewe

Intubation first-pass success in a high performing pre-hospital critical care system is not associated with 30-day mortality : a registry study of 4496 intubation attempts

Peer reviewe

Exploring unsupervised query paraphrasing to identify relevant search phrases for a literature review

Literature databases have multifaceted search options, but emerging research areas do not have an established terminology and therefore it is difficult to find relevant literature when conducting a review. This study aimed to explore if an unsupervised paraphrasing approach is useful in identifying relevant search phrases for a literature review on an emerging research topic – situational leadership in critical care. Using an initial set of 12 search phrases, the system was used to propose additional phrases, which were manually classified and further used in an expanded PubMed database search. Finally, we assessed the papers found with the expanded search and compared this to the initial search results. As a result, the expanded search more than tripled the search results, from 182 to 673 papers. The expanded search also more than tripled the number of relevant papers, from 12 in the original search to 39 in the expanded search.</p

Accuracy of prehospital clinicians' perceived prognostication of long-term survival in critically ill patients : a nationwide retrospective cohort study on helicopter emergency service patients

Objectives Prehospital critical care physicians regularly attend to patients with poor prognosis and may limit the advanced therapies. The aim of this study was to evaluate the accuracy of poor prognosis given by prehospital critical care clinicians. Design Cohort study. Setting We performed a retrospective cohort study using the national helicopter emergency medical services (HEMS) quality database. Participants Patients classified by the HEMS clinician to have survived until hospital admission solely because of prehospital interventions but evaluated as having no long-term survival by prehospital clinician, were included. Primary and secondary outcome The survival of the study patients was examined at 30 days, 1 year and 3 years. Results Of 36 715 patients encountered by the HEMS during the study period, 2053 patients were classified as having no long-term survival and included. At 30 days, 713 (35%, 95% CI 33% to 37%) were still alive and 69 were lost to follow-up. Furthermore, at 1 year 524 (26%) and at 3 years 267 (13%) of the patients were still alive. The deceased patients received more often prehospital rapid sequence intubation and vasoactives, compared with patients alive at 30 days. Patients deceased at 30 days were older and had lower initial Glasgow Coma Scores. Otherwise, no clinically relevant difference was found in the prehospital vital parameters between the survivors and non-survivors. Conclusions The prognostication of long-term survival for critically ill patients by a prehospital critical care clinician seems to fulfil only moderately. A prognosis based on clinical judgement must be handled with a great degree of caution and decision on limitation of advanced care should be made cautiously.Peer reviewe

Standardised data collection in prehospital critical care : a comparison of medical problem categories and discharge diagnoses

Background Prehospital medical problem reporting is essential in the management of helicopter emergency medical services (HEMS) operations. The consensus-based template for reporting and documenting in physician-staffed prehospital services exists and the classification of medical problems presented in the template is widely used in research and quality improvement. However, validation of the reported prehospital medical problem is lacking. This study aimed to describe the in-hospital diagnoses, patient characteristics and medical interventions in different categories of medical problems. Methods This retrospective, observational registry study examined the 10 most common in-hospital International Statistical Classification of Disease (ICD-10) diagnoseswithin different prehospital medical problem categories, defined by the HEMS physician/paramedic immediately after the mission was completed. Data were gathered from a national HEMS quality registry and a national hospital discharge registry. Patient characteristics and medical interventions related to different medical problem categories are also described. Results A total of 33,844 patients were included in the analyses. All the medical problem categories included a broad spectrum of ICD-10 diagnoses (the number of diagnosis classes per medical problem category ranged from 73 to 403). The most frequent diagnoses were mainly consistent with the reported medical problems. Overlapping of ICD-10 diagnoses was mostly seen in two medical problem categories: stroke and acute neurology excluding stroke. Additionally, typical patient characteristics and disturbances in vital signs were related to adequate medical problem categories. Conclusions Medical problems reported by HEMS personnel have adequate correspondence to hospital discharge diagnoses. However, the classification of cerebrovascular accidents remains challenging.Peer reviewe

Two cases of low birth weight infant survival by prehospital emergency hysterotomy

Background: During maternal cardiac arrest, emergency hysterotomy (EH) is recommended after four minutes of resuscitation, if no signs of spontaneous circulation are detected. This extreme procedure is believed to be potentially beneficial for both the mother and the infant. Both maternal and neonatal survivals seem to be associated to the time delay between the cardiac arrest and the delivery and in-hospital resuscitation location. In addition to this, gestational age is an important determinant to neonatal outcome.Case presentation: We report two emergency hysterotomies executed in an out-of-hospital location. The infants delivered by EH were low birth weight infants and born 20-23 min after maternal cardiac arrest. Both infants survived and had normal physical and neurological growth at the age of two years. Unfortunately, mothers in these both cases died in the field.Conclusion: Contrary to earlier beliefs, it is possible to perform a successful EH also in out-of-hospital setting, even with incomplete surgical skills. However, training and preparation are extremely important for achieving the highest possible readiness to treat maternal cardiac arrest situations also prehospitally

Accuracy of prehospital clinicians' perceived prognostication of long-term survival in critically ill patients: a nationwide retrospective cohort study on helicopter emergency service patients

Objectives Prehospital critical care physicians regularly attend to patients with poor prognosis and may limit the advanced therapies. The aim of this study was to evaluate the accuracy of poor prognosis given by prehospital critical care clinicians.Design Cohort study.Setting We performed a retrospective cohort study using the national helicopter emergency medical services (HEMS) quality database.Participants Patients classified by the HEMS clinician to have survived until hospital admission solely because of prehospital interventions but evaluated as having no long-term survival by prehospital clinician, were included.Primary and secondary outcome The survival of the study patients was examined at 30 days, 1 year and 3 years.Results Of 36 715 patients encountered by the HEMS during the study period, 2053 patients were classified as having no long-term survival and included. At 30 days, 713 (35%, 95% CI 33% to 37%) were still alive and 69 were lost to follow-up. Furthermore, at 1 year 524 (26%) and at 3 years 267 (13%) of the patients were still alive. The deceased patients received more often prehospital rapid sequence intubation and vasoactives, compared with patients alive at 30 days. Patients deceased at 30 days were older and had lower initial Glasgow Coma Scores. Otherwise, no clinically relevant difference was found in the prehospital vital parameters between the survivors and non-survivors.Conclusions The prognostication of long-term survival for critically ill patients by a prehospital critical care clinician seems to fulfil only moderately. A prognosis based on clinical judgement must be handled with a great degree of caution and decision on limitation of advanced care should be made cautiously.</p