Premature newborn positionings and physiologic parameters - a randomized clinical study / Posicionamentos de recém-nascidos prematuros e parâmetros fisiológicos - um estudo clínico randomizado

Abstract Introduction Multiple studies have shown the effects of prone (PP), supine (SP) and kangaroo (KP) positions on clinical and physiological outcomes in preterm newborns, but none compared these three types of positioning between them. Objective To investigate the influence of these positionings on heart rate, respiratory rate, peripheral oxygen saturation (SpO2) and alertness status in clinically stable preterm newborns (NBs) admitted to a neonatal intensive care unit. Methods In a randomized clinical trial, clinically stable NBs with gestational ages from 30 to 37 weeks who were breathing spontaneously were allocated in three positioning groups: PP, SP and KP. Heart rate, breathing frequency, SpO2 and alertness status were evaluated immediately before and after 30 minutes of positioning. Results In all, 66 NBs were assessed (corrected age: 35.48 ± 1.94 weeks; weight: 1840.14 ± 361.09 g), (PP: n = 22; SP: n = 23; KP: n = 21). NBs in the PP group showed a significant improvement in peripheral SpO2 (97.18 ± 2.16 vs 95.47 ± 2.93 vs 95.57 ± 2.95, p = 0.03) compared with the SP and KP groups. Conclusion In clinically stable preterm NBs, the PP was associated with better peripheral oxygen saturation than the SP or KP. In addition, there was a reduction in heart rate within prone position group and in the KP group there was an increase in the number of NBs in the deep sleep classification.

Resumo Introdução Vários estudos têm demonstrado os efeitos das posições prona (PP), supina (SP) e canguru (KP) sobre os resul-tados clínicos e fisiológicos em recém-nascidos prematuros, mas nenhum comparou esses três tipos de posicionamento. Objetivo Investigar a influência desses posicionamentos na frequência cardíaca, frequência respiratória, saturação periférica de oxigênio (SpO2) e estado de alerta em recém-nascidos pré-termo (RN) clinicamente estáveis internados em uma unidade de terapia intensiva neonatal. Métodos Em um ensaio clínico randomizado, RN clinicamente estáveis com idade gestacional de 30 a 37 semanas e respirando espontaneamente foram alocados em três grupos de posicionamento: PP, SP e KP. Frequência cardíaca e respiratória, SpO2 e estado de alerta foram avaliados imediatamente antes e após 30 minutos de posicionamento. Resultados Ao todo, foram avaliados 66 RNs (idade corrigida: 35,48 ± 1,94 semanas; peso: 1840,14 ± 361,09 g), (PP: n = 22; SP: n = 23; KP: n = 21). Os RNs do grupo PP apresentaram melhora significativa na SpO2 periférica (97,18 ± 2,16 vs 95,47 ± 2,93 vs 95,57 ± 2,95, p = 0,03) em comparação aos grupos SP e KP. Conclusão Em RN prematuros clinicamente estáveis, o PP foi associado à melhor saturação periférica de oxigênio do que o SP ou KP. Além disso, houve redução da frequência cardíaca no grupo de posição prona e no grupo KP houve aumento do número de RNs na classificação sono profundo.

Comparison of the effects of voluntary and involuntary breath stacking techniques on respiratory mechanics and lung function patterns in tracheostomized patients: a randomized crossover clinical trial / Comparação dos efeitos das técnicas breath stacking e air stacking sobre a mecânica respiratória e o padrão ventilatório em pacientes traqueostomizados: ensaio clínico cruzado randomizado

ABSTRACT Objective: To compare the effects of voluntary breath stacking (VBS) and involuntary breath stacking (IBS) techniques on respiratory mechanics, lung function patterns, and inspiratory capacity in tracheostomized patients. Methods: This was a randomized crossover clinical trial involving 20 tracheostomized patients admitted to the ICU and submitted to the VBS and IBS techniques, in random order, with an interval of 5 h between each. Ten cycles of each technique were performed with an interval of 30 s between each cycle. In VBS, patients performed successive inspirations for up to 30 s through a one-way valve, whereas in IBS, successive slow insufflations were performed with a resuscitator bag until the pressure reached 40 cmH2O. Respiratory mechanics, inspiratory capacity, and the lung function pattern were evaluated before and after the interventions. Results: After IBS, there was an increase in static compliance (p = 0.007), which was also higher after IBS than after VBS (p = 0.03). There was no significant difference between the pre-VBS and post-VBS evaluations in terms of static compliance (p = 0.42). Inspiratory capacity was also greater after IBS than after VBS (2,420.7 ± 480.9 mL vs. 1,211.3 ± 562.8 mL; p < 0.001), as was airway pressure (38.3 ± 2.6 cmH2O vs. 25.8 ± 5.5 cmH2O; p < 0.001). There were no changes in resistance or lung function pattern after the application of either technique. Conclusions: In comparison with VBS, IBS promoted greater inspiratory capacity and higher airway pressure, resulting in an increase in static compliance.

RESUMO Objetivo: Comparar os efeitos das técnicas breath stacking (BS) e air stacking (AS) sobre a mecânica respiratória, o padrão ventilatório e a capacidade inspiratória em pacientes traqueostomizados. Métodos: Ensaio clínico cruzado randomizado envolvendo 20 pacientes traqueostomizados internados em UTI e submetidos a ambas as técnicas, com intervalo de 5 h entre si, de acordo com a randomização. Foram realizados dez ciclos de cada técnica com intervalos de 30 segundos entre si. No BS, os pacientes realizaram inspirações sucessivas por até 30 s por meio de uma válvula unidirecional, enquanto no AS foram realizadas insuflações lentas sucessivas através de um ressuscitador manual até que a pressão atingisse 40 cmH2O. Os pacientes foram avaliados quanto a mecânica respiratória, capacidade inspiratória e padrão ventilatório antes e depois da realização das intervenções. Resultados: Com relação à mecânica respiratória no AS, houve aumento da complacência estática na comparação pré- e pós-intervenção (p = 0,007), assim como entre os momentos pós-AS e pós-BS (p = 0,03). Não houve diferença significativa da complacência estática na realização do BS (p = 0,42). A capacidade inspiratória foi maior após o AS que após o BS (2.420,7 ± 480,9 mL vs. 1.211,3 ± 562,8 mL; p < 0,001), bem como em relação à pressão nas vias aéreas (38,3 ± 2,6 cmH2O vs. 25,8 ± 5,5 cmH2O; p < 0,001). Não foram observadas alterações na resistência ou no padrão ventilatório em ambas as técnicas. Conclusões: Na presente amostra, o AS promoveu maior capacidade inspiratória e maior pressão nas vias aéreas que as observadas após o BS, com consequente aumento da complacência estática.

Efeitos agudos da hiperinsuflação com o ventilador com aumento do tempo inspiratório sobre a mecânica respiratória: ensaio clínico cruzado randomizado / Acute effects of ventilator hyperinflation with increased inspiratory time on respiratory mechanics: randomized crossover clinical trial

RESUMO Objetivo: Avaliar os efeitos da hiperinsuflação com o ventilador sobre a mecânica respiratória. Métodos: Foi realizado ensaio clínico cruzado randomizado com 38 pacientes ventilados mecanicamente com infecção pulmonar. A ordem da hiperinsuflação ou controle (sem alterações nos parâmetros) foi randomizada. A hiperinsuflação foi realizada por 5 minutos no modo ventilação com pressão controlada, com aumentos progressivos de 5cmH2O até atingir pressão máxima de 35cmH2O, mantendo-se a pressão positiva expiratória final. Após atingir 35cmH2O, o tempo inspiratório e a frequência respiratória foram ajustados para que os fluxos inspiratório e expiratório atingissem a linha de base, respectivamente. As medidas de complacência estática, resistências total e de vias aéreas e pico de fluxo expiratório foram avaliadas antes, imediatamente após a manobra e após aspiração. Foi utilizada a análise de variância two-way para medidas repetidas com pós-teste de Tukey, considerando significativo p < 0,05. Resultados: A hiperinsuflação com o ventilador aumentou a complacência estática, mantendo-se após aspiração (46,2 ± 14,8 versus 52,0 ± 14,9 versus 52,3 ± 16,0mL/cmH2O; p < 0,001). Houve aumento transitório da resistência de vias aéreas (6,6 ± 3,6 versus 8,0 ± 5,5 versus 6,6 ± 3,5cmH2O/L.s-1; p < 0,001) e redução transitória do pico de fluxo expiratório (32,0 ± 16,0 versus 29,8 ± 14,8 versus 32,1 ± 15,3Lpm; p < 0,05) imediatamente após a manobra, com redução após aspiração traqueal. Não foram observadas modificações no controle e nem alterações hemodinâmicas. Conclusão: A hiperinsuflação com o ventilador promoveu aumento da complacência associado ao aumento transitório da resistência de vias aéreas e do pico de fluxo expiratório, com redução após aspiração.

ABSTRACT Objective: To evaluate the effects of ventilator hyperinflation on respiratory mechanics. Methods: A randomized crossover clinical trial was conducted with 38 mechanically ventilated patients with pulmonary infection. The order of the hyperinflation and control (without changes in the parameters) conditions was randomized. Hyperinflation was performed for 5 minutes in pressure-controlled ventilation mode, with progressive increases of 5cmH2O until a maximum pressure of 35cmH2O was reached, maintaining positive end expiratory pressure. After 35cmH2O was reached, the inspiratory time and respiratory rate were adjusted so that the inspiratory and expiratory flows reached baseline levels. Measurements of static compliance, total resistance and airway resistance, and peak expiratory flow were evaluated before the technique, immediately after the technique and after aspiration. Two-way analysis of variance for repeated measures was used with Tukey's post hoc test, and p < 0.05 was considered significant. Results: Ventilator hyperinflation increased static compliance, which remained at the same level after aspiration (46.2 ± 14.8 versus 52.0 ± 14.9 versus 52.3 ± 16.0mL/cmH2O; p < 0.001). There was a transient increase in airway resistance (6.6 ± 3.6 versus 8.0 ± 5.5 versus 6.6 ± 3.5cmH2O/Ls-1; p < 0.001) and a transient reduction in peak expiratory flow (32.0 ± 16.0 versus 29.8 ± 14.8 versus 32.1 ± 15.3Lpm; p <0.05) immediately after the technique; these values returned to pretechnique levels after tracheal aspiration. There were no changes in the control condition, nor were hemodynamic alterations observed. Conclusion: Ventilator hyperinflation promoted increased compliance associated with a transient increase in airway resistance and peak expiratory flow, with reduction after aspiration.

Death patterns of patients in Department of Respiratory Care Unit of General Hospi-tal of PLA / 军事医学

Objective To analyze retrospectively the death pattern, risk factors, and death time of 253 patients at the Respiratory Care Unit of General Hospital of PLA in order to improve care quality and reduce mortality.Methods The information of patients was extracted from the hospital information system ( HIS) , and then classified and calculated accord-ing to different time points.Results Between November and next March,the mortality rate was higher than in other months (P<0.05), accounting for 19.5%.Mortality of those admitted between 8∶01 and 9∶00 or between 23∶01 and 24∶00 was higher than at other times(P<0.05), accounting for 41.7%and 50.0%, respectively.There was statistically significant difference(P<0.01) in mortality between days of the week,with the highest on Saturday, accounting for 43.1%.Mortality on non-work days was higher than on workday(P<0.01), accounting for 38.3% and 13.2%, respectively.Mortality at off-hour was higher than at office time(8∶00-11∶30 and 14∶30-18∶00 on workday) (P<0.01), accounting for 31.3%and 5.2%, respectively.Logistic regression analysis showed that age, month of admission, and the hour of discharge were associated with the outcome.Conclusion The high mortality between November and next March may be related to the higher incidence of respiratory diseases in winter, air pollution and cold weather.High mortality is also significantly associ-ated with the care quality of the medical staff.

Clinical and microbiological characterization of pneumonia in mechanically ventilated patients

OBJECTIVE: To characterize mechanical ventilation-associated pneumonia (MVAP). METHOD: This is an observational descriptive study to characterize MVAP in 61 ventilated patients admitted in the intensive care units of the Hermanos Ameijeiras hospital during 2011. This study also aimed to isolate the bacteria causing MVAP and characterize their resistance to antibiotics. RESULTS: 51 (83.60%) patients presented pulmonary infiltrates and 35 (50.81%) presented a clinical score > 6 according to the Clinical Pulmonary Infection Score. Acinetobacter baumannii and Pseudomonas aeruginosa were the most frequently isolated microorganisms from patients with MVAP. Both microorganisms showed a high resistance to antibiotics. Carbapenems were the most frequent used antimicrobial therapeutic agents; elective antibiotic combinations were directed against both bacterial wall structure and nucleic acid synthesis. CONCLUSION: Patients with MVAP identified during the studied period showed similar frequency to those reported in medical literature. Thus, this study corroborated that this is still a relevant medical problem in this hospital. Acinetobacter baumannii and Pseudomonas aeruginosa were the most frequently isolated microorganisms from patients with MVAP. Antimicrobial treatment, empirical or not, are still the main risk factors for the development of multidrug-resistant strains of bacteria. The rate of resistance to antibiotics of Acinetobacter baumannii and Pseudomonas aeruginosa strains isolated from patients with MVAP was higher than those isolated from infected patients without MAVP. Tigecycline and colistin were the only antibiotics fully effective against Acinetobacter baumannii strains isolated in 2011 from patients with MVAP; against Pseudomonas aeruginosa strains, only colistin was fully effective.

Characterization and sensitivity to antibiotics of bacteria isolated from the lower respiratory tract of ventilated patients hospitalized in intensive care units

OBJECTIVE: This observational study described the characterization of bacteria isolated from the lower respiratory tract of ventilated patients hospitalized in intensive care units. The demonstration of isolated microorganism resistance to antibiotics and a time-trend analysis of infection comparing a 48-month period were also other objectives. METHOD: Semi-quantitative assays of 1254 samples taken from 741 ventilated patients were performed, while pathogens were identified using the Enterotube II assay and VITEK 2 Compact equipment. Bacterial resistance to antibiotics was assessed by the Kirby-Bauer disc diffusion method and time-trend analysis of infection was based on data recorded by hospital microbiology laboratories. RESULTS: The most prevalent isolated bacteria from the patient's lower respiratory tract were with Gram-negative bacteria (67.8 percent) mostly represented by: Acinetobacter spp. (25.2 percent), Pseudomonas spp. (18.3 percent) and Klebsiellas spp. (9.4 percent). Acinetobacter spp. showed moderate high to very high resistance to ceftriaxone (CRO), gentamicin (CN), amikacin (AK), meropenem (MRP), aztreonam (ATM) and piperacillin/tazobactam (TZP). Some isolates of Acinetobacter spp. resistant to colistin (CS) were identified in this patient population. Pseudomonas spp. and Klebsiella spp. were very highly resistant to ampicillin/sublactam (AMS) and with moderate or low resistance to CRO, ATM, MRP, AK, CN and TZP. A decrease in the Pseudomonas spp. prevalence rate was observed, whereas an increase in Acinetobacter spp. and Klebsiella spp. prevalence rates were observed in a 48-month period. CONCLUSION: This research corroborated that these nosocomial infections are a relevant medical problem in our context. The most prevalent bacterial infections in the lower respiratory tract of ventilated patients were by Acinetobacter spp., Pseudomonas spp. and Klebsiella spp. The panel of antibiotics used as preventive therapy was not the solution of infections and probably induced drug-resistance mechanisms in these isolated microorganisms.