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PURPOSE: Thoracic trauma causes pain and hospitalisation. Middle- and high-income countries have different trauma contexts and populations. To report patients' clinical presentation (pain and shortness of breath) and its influence on hospital length of stay (LOS), acute care management, and discharge destinations in South Africa (SA) and Sweden.

METHODS: Prospective observational multicenter study by means of clinical record review. Two centers in SA and four centers in Sweden participated. One thousand nine hundred and eighteen adults with thoracic trauma were screened over the 20 months period. Study objectives guided information retrieved from clinical records. Statistical analysis was done with significance at p-value < 0.05.

RESULTS: Three-hundred-sixty-four participants were recruited with most being male (n = 170/179 (95%) SA; n = 125/185 (68%) Sweden). Type and mechanism of injury differed (SA penetrating (82%) versus Sweden blunt (95%); SA assaults (90%) versus Sweden falls (44%)). Unilateral haemopneumothorax was common (SA 68%, Sweden 35%) and managed with intercostal drainage. Rib cage injuries were common in the Swedish cohort with rib fixation surgery for 17%. Physiotherapy treatment frequency was mostly daily. Blunt injury resulted in higher pain levels during deep breathing (day 1: p = 0.014; day 2: p < 0.001; day 3: p < 0.001) and shortness of breath during activity (day 1: p = 0.036; day 2: p = 0.003; day 3: p < 0.001). LOS was shorter for SA cohort (5 (± 4) versus 7 (± 5) days; p = 0.024). Age influenced LOS in the blunt injury group. Discharge destination was mostly home (99% SA, 56% Sweden).

CONCLUSION: Priority care is indicated for those who are older and have blunt thoracic injury to prevent pulmonary complications and prolonged hospitalisation.

Objectives: The study aimed to describe and compare the clinical physiotherapy management of patients hospitalised due to chest trauma in South Africa (SA) and Sweden.

Design: A prospective observational multicentre international study.

Setting: Two university-Affiliated public sector hospitals in SA and four university-Affiliated public sector hospitals in Sweden.

Participants: In total, 364 adults, hospitalised due to chest trauma were consecutively recruited of which 179 were from SA and 185 were from Sweden.

Outcome measures: Physiotherapy practice was recorded in parallel with standard care. In addition, pulmonary complications and length of hospital stay were collected.

Results: Despite differences in the type of trauma between the national cohorts (83% penetrating traumas in SA and 95% blunt traumas in Sweden), most patients received physiotherapy treatment during the first 3 days in hospital. Physiotherapy interventions such as mobilisation (day 1: sit on edge of bed; days 1-3: walking) and exercises to maintain range of motion (days 1-3: shoulder; day 3: trunk) were initiated earlier in SA (p<0.05). Treatment with the active cycle of breathing technique was more used in SA while deep breathing exercises were more common in Sweden and positive expiratory pressure was common in both countries. Length of stay was in mean 5.4 (95% CI 4.8, 6.0) days in SA and 6.6 (5.8, 7.4) days in Sweden (p=0.024).

Conclusions: Despite differences in trauma panoramas and the national cohorts there seem to be similarities in clinical physiotherapy practices between the two countries.

Objectives: To describe the timing and type of the first targeted breathing exercises after abdominal and cardiothoracic surgery, and to identify factors associated with early initiation (Commencement within three hours after arriival to a postoperative ward).

Design: Multicentre observational study.

Methods: In 18 hospitals in Sweden, the start time and type of targeted breathing exercises were recorded in consecutive series of patients who underwent abdominal or cardiothoracic surgery. Demographic data were retrieved from hospital records. Patients were divided into seven groups based on the category of surgery.

Results: In total, 1492 patients were included in this study; of these, 1128 (76%) performed some form of targeted breathing exercise after surgery. Targeted breathing exercises commenced a median of 3.63 hours (interquartile range 1.58 to 11.75 hours) after arrival on a postoperative ward, with earlier commencement after minor abdominal surgery and later commencement after major abdominal surgery (P < 0.001). Most patients who performed targeted breathing exercises used positive expiratory pressure (n = 968/1492, 65%) or deep breathing without any devices (n = 207/1492, 14%). The odds of initiating breathing exercises within the first 3 hours after arrival on a postoperative ward were higher if a patient underwent pulmonary or abdominal surgery [odds ratio (OR) > 2.04; P < 0.001], or had intravenous analgesia (OR 1.50, 95% CI 1.05 to 2.14; P = 0.026). The odds were lower (OR 0.43, 95% CI 0.21 to 0.88; P = 0.021) for patients who arrived on the postoperative ward in the evening/night or for patients who had undergone laparoscopic surgery (OR 0.63, 0.43-0.92, p=0.018).

Conclusion: The majority (76%) of patients undergoing abdominal or cardiothoracic surgery performed some form of targeted breathing exercise, starting a median of 3.63 hours after arrival on a postoperative ward.

BACKGROUND: Cardiac surgery is associated with a period of postoperative bed rest. Although early mobilization is a vital component of postoperative care, for preventing complications and enhancing physical recovery, there is limited data on routine practices and optimal strategies for early mobilization after cardiac surgery. The aim of the study was to define the timing for the first initiation of out of bed mobilization after cardiac surgery and to describe the type of mobilization performed.

METHODS: In this observational study, the first mobilization out of bed was studied in a subset of adult cardiac surgery patients (n = 290) from five of the eight university hospitals performing cardiothoracic surgery in Sweden. Over a five-week period, patients were evaluated for mobilization routines within the initial 24 h after cardiac surgery. Data on the timing of the first mobilization after the end of surgery, as well as the duration and type of mobilization, were documented. Additionally, information on patient characteristics, anesthesia, and surgery was collected.

RESULTS: A total of 277 patients (96%) were mobilized out of bed within the first 24 h, and 39% of these patients were mobilized within 6 h after surgery. The time to first mobilization after the end of surgery was 8.7 ± 5.5 h; median of 7.1 [4.5-13.1] hours, with no significant differences between coronary artery bypass grafting, valve surgery, aortic surgery or other procedures (p = 0.156). First mobilization session lasted 20 ± 41 min with median of 10 [1-11]. Various kinds of first-time mobilization, including sitting on the edge of the bed, standing, and sitting in a chair, were revealed. A moderate association was found between longer intubation time and later first mobilization (ρ = 0.487, p < 0.001). Additionally, there was a moderate correlation between the first timing of mobilization duration of the first mobilization session (ρ = 0.315, p < 0.001).

CONCLUSIONS: This study demonstrates a median time to first mobilization out of bed of 7 h after cardiac surgery. A moderate correlation was observed between earlier timing of mobilization and shorter duration of the mobilization session. Future research should explore reasons for delayed mobilization and investigate whether earlier mobilization correlates with clinical benefits.

TRIAL REGISTRATION: FoU in VGR (Id 275,357) and Clinical Trials (NCT04729634).

Objectives: Knowledge of clinical practice regarding mobilisation after surgery is lacking. This study therefore aimed to reveal current mobilisation routines after abdominal and cardiothoracic surgery and to identify factors associated with mobilisation within 6 hours postoperatively.

Design: A prospective observational national multicentre study.

Setting: 18 different hospitals in Sweden.

Participants: 1492 adult patients undergoing abdominal and cardiothoracic surgery with duration of anaesthesia>2 hours.

Primary and secondary outcomes: Primary outcome was time to first postoperative mobilisation. Secondary outcomes were the type and duration of the first mobilisation. Data were analysed using multivariate logistic regression and general structural equation modelling, and data are presented as ORs with 95% CIs.

Results: Among the included patients, 52% were mobilised to at least sitting on the edge of the bed within 6 hours, 70% within 12 hours and 96% within 24 hours. Besides sitting on the edge of the bed, 76% stood up by the bed and 22% were walking away from the bedside the first time they were mobilised. Patients undergoing major upper abdominal surgery required the longest time before mobilisation with an average time of 11 hours post surgery. Factors associated with increased likelihood of mobilisation within 6 hours of surgery were daytime arrival at the postoperative recovery unit (OR: 5.13, 95% CI: 2.16 to 12.18), anaesthesia <4 hours (OR: 1.68, 95% CI: 1.17 to 2.40) and American Society of Anaesthesiologists (ASA) classification 1-2, (OR: 1.63, 95% CI: 1.13 to 2.36).

Conclusions: In total, 96% if the patients were mobilised within 24 hours after surgery and 52% within 6 hours. Daytime arrival at the postoperative recovery unit, low ASA classification and shorter duration of anaesthesia were associated with a shorter time to mobilisation.

Trial registration number: FoU, Forskning och Utveckling in VGR, Vastra Gotaland Region (Id:275357) and Clinical Trials (NCT04729634).

BACKGROUND: Positive expiratory pressure (PEP) and CPAP are used to enhance breathing parameters such as functional residual capacity (FRC) in patients. Studies comparing effects of PEP and CPAP on FRC are few and variable. One reason for this may be that sophisticated equipment, not suitable in the clinical setting, is required. Because total lung capacity (TLC) consists of inspiratory capacity (IC) and FRC, a change in IC should result in a corresponding change in FRC given constant TLC. We aimed to evaluate the effects of different PEP and CPAP devices on IC as an indirect measure of induced changes in FRC from these devices in healthy subjects. METHODS: Twenty healthy subjects breathed with 2 PEP devices, a PEP mask (flow resistor) and a PEP bottle (threshold resistor), and 2 CPAP devices, a flow resistor and a threshold resistor, in a randomized order. The measurement sequence consisted of 30 breaths with an IC measurement performed before and immediately after the 30th breath while the subjects were still connected to the breathing device. Perceived exertion of the 30 breaths was measured with the Borg category ratio 10 scale. RESULTS: Three of the 4 breathing devices, the PEP mask and the 2 CPAP devices, significantly decreased IC (P <.001). Median perceived exertion was quite low for all 4 breathing devices, but the difference in perceived exertion among the different breathing devices was large. CONCLUSIONS: Provided that TLC is constant, we found that measurements of changes in IC could be used as an indirect measure of changes in FRC in healthy subjects. All investigated breathing devices except the PEP bottle decreased IC, as an indirect measure of increased FRC.

Background: Positive expiratory pressure (PEP) and continuous positive airway pressure (CPAP) are two forms of resistance breathing used in spontaneously breathing patients. With a threshold resistor or a flow resistor, both PEP and CPAP provide a positive (elevated) pressure level during the expiratory phase. With PEP, inspiratory pressure is negative, i.e. lower than ambient air pressure, as during a normal inspiration, but with CPAP, the inspiratory pressure is positive, i.e. higher than ambient air pressure.

Methods: This thesis is based on four separate studies in which four different breathing devices, a PEP-bottle (threshold resistor device), a PEP-mask (flow resistor device), a threshold resistor CPAP and a flow resistor device were investigated. Paper I, II and III are based on studies in healthy volunteers. Paper IV is a bench study performed in a hypobaric chamber. Paper I examined differences between two PEP devices, the PEP-bottle and the PEP-mask. Paper II evaluated the performance of a flow resistor CPAP device, (Boussignac CPAP). Paper III investigated the effect of two PEP-devices, a PEP-bottle and a PEP-mask and two CPAP devices, a threshold resistor CPAP and a flow resistor CPAP, on inspiratory capacity (IC). In paper IV, the effect of changes in ambient pressure on preset CPAP levels in two different CPAP devices was compared.

Results: With the PEP bottle, both expiration and inspiration began with a zero-flow period during which airway pressure changed rapidly. With the PEP-mask, the zero-flow period was very short and the change in airway pressure almost non-existent (paper I). During normal breathing with the Boussignac CPAP, changes in airway pressure were never large enough to reduce airway pressure below zero. During forced breathing, as airflow increased, both the drop in inspiratory airway pressure and the increase in expiratory airway pressure were potentiated (paper II). IC decreased significantly with three of the breathing devices, the PEP-mask and the two CPAP devices (paper III). With the threshold resistor CPAP, measured pressure levels were close to the preset CPAP level. With the flow resistor CPAP, as the altitude increased CPAP produced pressure levels increased (paper IV).

Conclusion: The effect on airway pressure, airflow, IC and the effect of changes in ambient air pressure differ between different kinds of resistance breathing devices. These differences in device performance should be taken into consideration when choosing the optimal resistance breathing device for each patient.

INTRODUCTION: Continuous positive airway pressure (CPAP) is used in air ambulances to treat patients with impaired oxygenation. Differences in mechanical principles between CPAP devices may affect their performance at different ambient air pressures as will occur in an air ambulance during flight. METHODS: Two different CPAP systems, a threshold resistor device and a flow resistor device, at settings 5 and 10 cm H₂O were examined. Static pressure, static airflow and pressure during simulated breathing were measured at ground level and at three different altitudes (2400 m (8 kft), 3000 m (10 kft) and 10700 m (35 kft)). RESULTS: When altitude increased, the performance of the two CPAP systems differed during both static and simulated breathing pressure measurements. With the threshold resistor CPAP, measured pressure levels were close to the preset CPAP level. Static pressure decreased 0.71 ± 0.35 cm H₂O, at CPAP 10 cm H₂O, comparing ground level and 35 kft. With the flow resistor CPAP, as the altitude increased CPAP produced pressure levels increased. At 35 kft, the increase was 5.13 ± 0.33 cm H₂O at CPAP 10 cm H₂O. DISCUSSION: The velocity of airflow through the flow resistor CPAP device is strongly influenced by reduced ambient air pressure leading to a higher delivered CPAP effect than the preset CPAP level. Threshold resistor CPAP devices seem to have robust performance regardless of altitude. Thus, the threshold resistor CPAP device is probably more appropriate for CPAP treatment in an air ambulance cabin, where ambient pressure will vary during patient transport.

BACKGROUND: The Boussignac CPAP has been found to effectively treat acute pulmonary oedema. However, data on airway pressure in association with the Boussignac CPAP are sparse. We therefore designed this study to evaluate the stability of the Boussignac CPAP in terms of maintaining adequate inspiratory and expiratory pressure levels. We also wanted to evaluate the perceived exertion when breathing with the Boussignac CPAP.

METHODS: Continuous recordings of airway pressure and airflow were made in 18 healthy volunteers during breathing with the Boussignac CPAP at 5, 7.5 and 10 cm H₂O for three sessions of 10 minutes at each CPAP level. Participants were blinded for the sequential order of the investigated CPAP levels. They terminated each session, at the respective CPAP level, by taking 10 forced breaths.

RESULTS: During 10 minutes normal breathing periods, when participants breathed at 20 % of their VC with a peak expiratory airflow of 14 % of FEV₁, the maximal pressure difference was 4.0 cm H₂O between inspiration and expiration at CPAP 10 cm H₂O. Changes in airway pressure were never large enough to reduce airway pressure below zero. When taking forced breaths, expiratory volume was 38-42 % of VC and peak expiratory airflow was 49-56 % of FEV ₁. As airflow increased, both the drop in inspiratory airway pressure and the increase in expiratory airway pressure were enhanced.

CONCLUSIONS: Pressure changes during breathing with CPAP are considered to be associated with increased work of breathing. The pneumatic performance of the Boussignac CPAP is adequate during normal breathing with low airflow. However, during forced breathing resulting in increased airflow, the Boussignac CPAP is unable to maintain stable airway pressure levels, possibly resulting in increased work of breathing and respiratory fatigue. Thus, the Boussignac CPAP system might be less suitable for patients breathing at a higher frequency.

BACKGROUND: In the intensive care unit we have observed that patients have different adherence to 2 commonly used positive-expiratory-pressure (PEP) therapy devices: the PEP bottle and the PEP mask. The reason for this difference is not clear. METHODS: In a randomized prospective study, we made continuous recordings of airway pressure and airflow, with 20 healthy volunteers, with the PEP bottle and the PEP mask. The measurement sequence consisted of 3 sessions of 10 breaths with the PEP bottle and the PEP mask, in a randomized crossover design. A rest period of 15 min separated the PEP bottle and PEP mask measurements. RESULTS: With the PEP bottle the expiratory phase began with a zero-flow period of 0.39 s, during which airway pressure rose 11.9 cm H2O. With the PEP bottle the mean expiratory pressure was 11.7 cm H2O, and end-expiratory pressure was 9.5 cm H2O. With the PEP mask the initial expiratory zero-flow period was almost nonexistent (0.04 s) and without any change in airway pressure. With the PEP mask the shape of the expiratory pressure curve was different; mean expiratory pressure was 8.6 cm H2O, and end-expiratory pressure was zero. With the PEP bottle the inspiration also began with a zero-flow period of 0.43 s, during which airway pressure decreased 9.6 cm H2O from the end-expiratory airway pressure. With the PEP mask the initial inspiratory zero-flow period was only 0.01 s and there was no concomitant change in airway pressure. CONCLUSIONS: The PEP bottle and the PEP mask showed major differences in the relationship between airflow and airway pressure. These findings might explain the observed differences in patient adherence to these therapies.