Tracheal tube biofilm removal through a novel closed-suctioning system: an experimental study.

BACKGROUND: Tracheal tube biofilm develops during mechanical ventilation. We compared a novel closed-suctioning system vs standard closed-suctioning system in the prevention of tracheal tube biofilm. METHODS: Eighteen pigs, on mechanical ventilation for 76 h, with P. aeruginosa pneumonia were randomized to be tracheally suctioned via the KIMVENT* closed-suctioning system (control group) or a novel closed-suctioning system (treatment group), designed to remove tracheal tube biofilm through saline jets and an inflatable balloon. Upon autopsy, two tracheal tube hemi-sections were dissected for confocal and scanning electron microscopy. Biofilm area, maximal and minimal thickness were computed. Biofilm stage was assessed. RESULTS: Sixteen animals were included in the final analysis. In the treatment and control group, the mean (sd) pulmonary burden was 3.34 (1.28) and 4.17 (1.09) log cfu gr(-1), respectively (P=0.18). Tracheal tube P. aeruginosa colonization was 5.6 (4.9-6.3) and 6.2 (5.6-6.9) cfu ml(-1) (median and interquartile range) in the treatment and control group, respectively (P=0.23). In the treatment group, median biofilm area was 3.65 (3.22-4.21) log10 µm2 compared with 4.49 (4.27-4.52) log10 µm2 in the control group (P=0.031). In the treatment and control groups, the maximal biofilm thickness was 48.3 (26.7-71.2) µm (median and interquartile range) and 88.8 (43.8-125.7) µm, respectively. The minimal thickness in the treatment and control group was 0.6 (0-4.0) µm and 23.7 (5.3-27.8) µm (P=0.040) (P=0.017). Earlier stages of biofilm development were found in the treatment group (P<0.001). CONCLUSIONS: The novel CSS reduces biofilm accumulation within the tracheal tube. A clinical trial is required to confirm these findings and the impact on major outcomes.

Chest physiotherapy for the prevention of ventilator-associated pneumonia.

OBJECTIVE: Pneumonia is an important complication in patients who are intubated and mechanically ventilated, when it is commonly referred to as ventilator-associated pneumonia (VAP). Since VAP may be contributed to by impaired sputum clearance, we studied whether chest physiotherapy designed to enhance sputum clearance decreases the occurrence of VAP. DESIGN: Prospective controlled systematic allocation trial. SETTING: Tertiary teaching hospital ICU. PATIENTS AND PARTICIPANTS: Sixty adult patients intubated and mechanically ventilated for at least 48 h. INTERVENTIONS: Chest physiotherapy (intervention group) or sham physiotherapy (control group). MEASUREMENTS AND RESULTS: Control and intervention groups were well matched for age, sex, and admission PaO(2)/FiO(2) ratio, APACHE II score, and Glasgow Coma Score. There were no differences in the duration of mechanical ventilation, length of stay in ICU or mortality. VAP was assessed daily by combined clinical assessment and the clinical pulmonary infection score (CPIS). VAP occurred in 39% (14/36) of the control group and 8% (2/24) of the intervention group (OR = 0.14, 95% CI 0.03 to 0.56, P = 0.02). After adjustment was made by logistic regression for other important variables (APACHE II score, duration of mechanical ventilation, presence of tracheostomy, and GCS score), chest physiotherapy was independently associated with a reduced occurrence of VAP (adjusted OR = 0.16, 95% CI 0.03 to 0.94, P = 0.02). CONCLUSIONS: In this small trial, chest physiotherapy in ventilated patients was independently associated with a reduction in VAP. This suggested benefit of physiotherapy in prevention of VAP requires confirmation with a larger randomised controlled trial.

Variation in the provision of cardiothoracic physiotherapy in Australian hospitals.

The chief physiotherapists of 47 Australian metropolitan public hospitals were asked about the hours of provision and organisation of cardiothoracic physiotherapy services. Forty three per cent provided physiotherapy services only during the day, 12 per cent during the day and evening, and 45 per cent provided 24-hour coverage. Variation among the states was found in the provision of cardiothoracic physiotherapy. Most hospitals which provided 24-hour coverage used on-call. Thirty three per cent of hospitals rostered staff to work during the evening and only 7 per cent had rostered night shifts. Differences could not be attributed to variations in hospital size. The implications of these findings for the physiotherapy profession and patient care are discussed and the need for further research highlighted.

A randomized controlled trial comparing periodic mask CPAP with physiotherapy after abdominal surgery.

BACKGROUND AND PURPOSE: Physiotherapists use a variety of techniques aimed at improving lung volumes and secretion clearance in patients after surgery. Periodic continuous positive airway pressure (PCPAP) is used to treat patients following elective upper abdominal surgery. However, the optimal method of application has not been identified, more specifically, the dosage of application of PCPAP. The present randomized controlled trial compared the effects of two dosages of PCPAP application and 'traditional' physiotherapy upon functional residual capacity (FRC), vital capacity (VC), oxyhaemoglobin saturation (SpO2), incidence of post-operative pulmonary complications and length of stay with a control group receiving 'traditional' physiotherapy only. METHOD: Fifty-seven subjects were randomly allocated to one of three groups. All groups received 'traditional' physiotherapy twice daily for a minimum of three post-operative days. In addition, two groups received PCPAP for 15 or 30 minutes, four times per day, for three days. RESULTS: Fifty subjects (39 male; 11 female) completed the study. There were no significant differences in any variables between the three groups. The overall incidence of post-operative pulmonary complications was 22% in the control group, 11% and 6% in the PCPAP 15-minute and PCPAP 30-minute groups, respectively. Length of hospital stay was not significantly different between the groups but for subjects who developed post-operative pulmonary complications, the length of stay was significantly greater (Z = -2.32; p = 0.021). CONCLUSIONS: The addition of PCPAP to a traditional physiotherapy post-operative treatment regimen after upper abdominal surgery did not significantly affect physiological or clinical outcomes.

Justification for chest physiotherapy during ultra-protective lung ventilation and extra-corporeal membrane oxygenation: a case study.

BACKGROUND AND PURPOSE: This case report describes the chest physiotherapy (CPT) intervention provided to a 32-year old man with severe respiratory failure undergoing extra-corporeal membrane oxygenation (ECMO) support and ultra-protective ventilatory strategy. Low tidal volume ventilation when used in patients with extremely low dynamic respiratory compliance may predispose the patient to secretion retention, and the role of CPT in this setting is unclear. METHOD: The method used is a single subject case report. Written consent obtained from patient's representative. SUMMARY: Secretion clearance in this patient was initially limited to suctioning; however, after developing major airway occlusion secondary to impacted secretions, he received intensive CPT consisting of positioning, ventilator hyperinflation, expiratory chest wall shaking and suctioning. After 13 days of two to three times daily CPT, the patient weaned from ECMO support. DISCUSSION: Regular CPT may have facilitated secretion clearance and lung recovery in this patient. Future research should investigate the optimal CPT techniques for patients with sub-dead space tidal ventilation and extremely low dynamic respiratory compliance during ECMO with ultra-protective ventilatory strategy (UPVS).

Computerised lung sound monitoring to assess effectiveness of chest physiotherapy and secretion removal: a feasibility study.

OBJECTIVES: To explore the feasibility of computerised lung sound monitoring to evaluate secretion removal in intubated and mechanically ventilated adult patients. DESIGN: Before and after observational investigation. SETTING: Intensive care unit. PARTICIPANTS: Fifteen intubated and mechanically ventilated adult patients receiving chest physiotherapy. INTERVENTIONS: Chest physiotherapy included combinations of standard closed airway suctioning, saline lavage, postural drainage, chest wall vibrations, manual-assisted cough and/or lung hyperinflation, dependent upon clinical indications. MAIN OUTCOME MEASURES: Lung sound amplitude at peak inspiration was assessed using computerised lung sound monitoring. Measurements were performed immediately before and after chest physiotherapy. Data are reported as mean [standard deviation (SD)], mean difference and 95% confidence intervals (CI). Significance testing was not performed due to the small sample size and the exploratory nature of the study. RESULTS: Fifteen patients were included in the study [11 males, four females, mean age 65 (SD 14) years]. The mean total lung sound amplitude at peak inspiration decreased two-fold from 38 (SD 59) units before treatment to 17 (SD 19) units after treatment (mean difference 22, 95% CI of difference -3 to 46). The mean total lung sound amplitude from the lungs of patients with a large amount of secretions (n=9) was over four times 'louder' than the lungs of patients with a moderate or small amount of secretions (n=6) [56 (SD 72) units vs 12 (13) units, respectively; mean difference -44, 95% CI of difference -100 to 11]. The mean total lung sound amplitude decreased in the group of 'loud' right and left lungs (n=15) from 37 (SD 36) units before treatment to 15 (SD 13) units after treatment (mean difference 22, 95% CI of difference 6 to 38). CONCLUSION: Computerised lung sound monitoring in this small group of patients demonstrated a two-fold decrease in lung sound amplitude following chest physiotherapy. Subgroup analysis also demonstrated decreasing trends in lung sound amplitude in the group of 'loud' lungs following chest physiotherapy. Due to the small sample size and large SDs with high variability in the lung sound amplitude measurements, significance testing was not reported. Further investigation is needed in a larger sample of patients with more accurate measurement of sputum wet weight in order to distinguish between secretion-related effects and changes due to other factors such as airflow rate and pattern.

Indications for manual lung hyperinflation (MHI) in the mechanically ventilated patient with chronic obstructive pulmonary disease.

Manual lung hyperinflation (MHI) can enhance secretion clearance, improve total lung/thorax compliance and assist in the resolution of acute atelectasis. To enhance secretion clearance in the intubated patient, the evidence highlights the need to maximize expiratory flow. Chronic pulmonary diseases such as chronic obstructive pulmonary disease (COPD) have often been cited as potential precautions and/or contra-indications to the use of manual lung hyperinflation (MHI). There is an absence of evidence on the effects of MHI in the patient with COPD. Research on the effects of mechanical ventilation in the patient with COPD provides a useful clinical examination of the effect of positive pressure on cardiac and pulmonary function. The potential effects of MHI in the COPD patient group were extrapolated on the basis of the MHI and mechanical ventilation literature. There is the potential for MHI to have both detrimental and beneficial effects on cardiac and pulmonary function in patients with COPD. The potential detrimental effects of MHI may include either, increased intrinsic peep through inadequate time for expiration by the breath delivery rate, tidal volume delivered or through the removal of applied external PEEP thereby causing more dynamic airway compression compromising downward expiratory flow, which may also retard bronchial mucus transport. MHI may also increase right ventricular after load through raised intrathoracic pressures with lung hyperinflation, and may therefore impair right ventricular function in patients with evidence of cor pulmonale. There is the potential for beneficial effects from MHI in the intubated COPD patient group (i.e., secretion clearance), but further research is required, especially on the effect of MHI on inspiratory and expiratory flow rate profiles in this patient group. The more controlled delivery of lung hyperinflation through the use of the mechanical ventilator may be a more optimal means of providing lung hyperinflation and should be further investigated.

The effect of manual lung hyperinflation and postural drainage on pulmonary complications in mechanically ventilated trauma patients.

This study questioned whether manual lung hyperinflation (MHI) and postural drainage reduced the incidence of nosocomial pneumonia or improved other outcome variables in mechanically ventilated trauma patients. Patients were withdrawn from the study if they developed nosocomial pneumonia according to a predetermined definition or on the clinical suspicion of nosocomial pneumonia by the attending intensivist. Of the 46 patients who fulfilled all the inclusion criteria and were enrolled into the study, 22 patients were randomized to group A (physiotherapy) and 24 patients to group B (control group). Twice as many patients were withdrawn in group B (8/24) compared with group A (4/22), although the differences were not statistically significant, [X2(1, 1) = 1.36, P = 0.24]. The length of time receiving mechanical ventilation and in the ICU was similar between the two groups and there were no differences in pulmonary dysfunction ("worst" daily PaO2/FiO2 ratio) between the two groups. There were no ICU deaths in either group. Physiotherapy as used in this study was not associated with a reduced incidence of nosocomial pneumonia based on standard clinical criteria. Nevertheless the trend to more frequent nosocomial pneumonia in the control patients suggests that a larger study in more severely injured patients with stricter clinical criteria for the definition of nosocomial pneumonia is indicated.

Non-invasive ventilation assists chest physiotherapy in adults with acute exacerbations of cystic fibrosis.

BACKGROUND: Chest physiotherapy is essential to the management of cystic fibrosis (CF). However, respiratory muscle fatigue and oxygen desaturation during treatment have been reported. The aim of this study was to determine whether non-invasive ventilation (NIV) during chest physiotherapy could prevent these adverse effects in adults with exacerbations of CF. METHODS: Twenty six patients of mean (SD) age 27 (6) years and forced expiratory volume in 1 second (FEV1) 34 (12)% predicted completed a randomised crossover trial comparing standard treatment (active cycle of breathing technique, ACBT) with ACBT + NIV. Respiratory muscle strength (PImax, PEmax), spirometric parameters, and dyspnoea were measured before and after treatment. Pulse oximetry (SpO2) was recorded during treatment. Sputum production during treatment and 4 and 24 hours after treatment was evaluated. RESULTS: There was a significant reduction in PImax following standard treatment that was correlated with baseline PImax (r=0.73, p<0.001). PImax was maintained following NIV (mean difference from standard treatment 9.04 cm H2O, 95% confidence interval (CI) 4.25 to 13.83 cm H2O, p=0.006). A significant increase in PEmax was observed following the NIV session (8.04 cm H2O, 95% CI 0.61 to 15.46 cm H2O, p=0.02). The proportion of treatment time with SpO2 < or =90% was correlated with FEV1 (r=-0.65, p<0.001). NIV improved mean SpO2 (p<0.001) and reduced dyspnoea (p=0.02). There were no differences in FEV1, forced vital capacity (FVC) or sputum weight, but FEF(25-75) increased following NIV (p=0.006). CONCLUSION: Reduced inspiratory muscle strength and oxygen desaturation during chest physiotherapy are associated with inspiratory muscle weakness and severity of lung disease in adults with exacerbations of CF. Addition of NIV improves inspiratory muscle function, oxygen saturation and small airway function and reduces dyspnoea.

An investigation of the early effects of manual lung hyperinflation in critically ill patients.

This prospective within-group multicentre study was designed to assess the safety and short-term effectiveness of manual lung hyperinflation in mechanically ventilated patients. Eighteen patients from the intensive care units of two tertiary institutions were included and acted as their own control. Manual lung hyperinflation treatment involved patient positioning (side-lying), suctioning and manual lung hyperinflation. Side-lying treatment involved patient positioning and suctioning alone. Patients received both treatments on the day of data collection. Results demonstrated significant improvement for static respiratory system compliance (P = 0.001) with manual lung hyperinflation treatment compared to side-lying treatment. Manual lung hyperinflation treatment also cleared a significantly greater wet weight of sputum (P = 0.039). There were no differences between manual lung hyperinflation and side-lying treatment for gas exchange (PaO2/FIO2 and PaCO2), mean arterial pressure or heart rate. In conclusion, total static respiratory system compliance and sputum clearance were improved by the addition of manual hyperinflation to a physiotherapy treatment of positioning and suctioning in mechanically ventilated patients without compromise to cardiovascular stability or gas exchange.