Physiotherapist administered, non-invasive ventilation to reduce postoperative pulmonary complications in high-risk patients following elective upper abdominal surgery; a before-and-after cohort implementation study.

OBJECTIVES: To (1) determine whether short, 30-minute sessions of non-invasive ventilation (NIV) is associated with fewer postoperative pulmonary complications (PPC) following elective high-risk upper abdominal surgery and (2) measure feasibility and safety of this intervention when delivered by physiotherapists. DESIGN: Prospective, pre post cohort, observational, single-centre study. SETTING: Primary referral hospital in Australia. PARTICIPANTS: A total of 182 consecutive high-risk elective upper abdominal surgery patients consisting of 101 pre cohort participants compared to 81 post cohort participants. INTERVENTIONS: Both groups received standardised preoperative physiotherapy and early postoperative mobilisation. The post cohort group received five additional 30-minute NIV sessions in the first two postoperative days. MAIN OUTCOME MEASURE: Primary outcome measure was PPC incidence within the first seven postoperative days. Secondary outcomes included feasibility and safety of physiotherapy-led NIV. RESULTS: Incidence of PPC (7% vs 18%, adjusted relative risk 0.24; 95% CI 0.10 to 0.59, p=0.002) was less in the NIV group compared to those who received no NIV. Mean time to first NIV session was 18.6 (SD 11.0) hours with 74% of participants receiving NIV within 24-hours of surgery. There were no major adverse events. CONCLUSION: These findings suggest PPC reduction may be possible with postoperative NIV following high-risk elective upper abdominal surgery. Results should be seen as hypothesis-generating associations only considering the significant limitations to this study. Physiotherapy-led NIV was delivered safely to ICU and ward patients. However, the planned protocol was not feasible and appropriate physiotherapy staffing and/or a multidisciplinary approach may be required to provide this service successfully. TRIAL REGISTRATION: LIPPSMAck POP (Lung Infection Prevention Post Surgery - Major Abdominal - with Pre Operative Physiotherapy) ANZCTR-12613000664741 (for pre cohort group only).

Development of a physiotherapy-led bronchoscopy service: a regional hospital perspective.

Extended scope of practice (ESoP) and advanced scope of practice (ASoP) physiotherapy roles have been in place in the UK for over 20 years. However, interest in these types of services appears to be only just evolving within Australia. Although ESoP and/or ASoP cardiorespiratory roles in intensive care units (ICU) may be perceived to be more achievable in large metropolitan teaching hospitals, at least 67% of Australian ICUs provide physiotherapy services. Very little has been published on the practicalities (e.g. training pathways, evidence for use and guidelines) of developing advanced or extended scope cardiorespiratory physiotherapy services within Australian ICUs. This report describes the development and implementation of a physiotherapy-led bronchoscopy service from a regional hospital perspective.

Magnesium flux during continuous venovenous haemodiafiltration with heparin and citrate anticoagulation.

OBJECTIVE: To describe magnesium flux and serum concentrations in ICU patients receiving continuous venovenous haemodiafiltration (CVVHDF). DESIGN: Samples were collected from 22 CVVHDF circuits using citrate anticoagulation solutions (Prismocitrate 10/2 and Prism0cal) and from 26 circuits using Hemosol B0 and heparin anticoagulation. CVVHDF prescription, magnesium supplementation and anticoagulation choice was by the treating intensivist. We analysed 334 sample sets consisting of arterial, prefilter and postfilter blood and effluent. Magnesium loss was calculated from an equation for conservation of mass, and arterial magnesium concentration was described by an equation for exponential decay. RESULTS: Using flow rates typical of adults receiving CVVHDF, we determined a median half-life for arterial magnesium concentration to decay to a new steady state of 4.73 hours (interquartile range [IQR], 3.73-7.32 hours). Median arterial magnesium concentration was 0.88mmol/L (IQR, 0.83-0.97mmol/L) in the heparin group and 0.79mmol/L (IQR, 0.69-0.91mmol/L) in the citrate group. Arterial magnesium concentrations fell below the reference range regularly in the citrate group and, when low, there was magnesium flux from dialysate to patient. Magnesium loss was greater in patients receiving citrate. CONCLUSIONS: Exponential decline in magnesium concentrations was sufficiently rapid that subtherapeutic serum magnesium concentrations may occur well before detection when once-daily sampling was used. Measurements should be interpreted with regard to timing of magnesium infusions. We suggest that continuous renal replacement therapy fluids with higher magnesium concentrations be introduced in the critical care setting.

Calcium flux in continuous venovenous haemodiafiltration with heparin and citrate anticoagulation.

BACKGROUND: Calcium chelation with citrate is an effective alternative to heparin for anticoagulation of the extracorporeal circuit during continuous venovenous haemodiafiltration (CVVHD-F). Calcium release occurs upon citrate metabolism; however, ultrafiltration of citrate-bound and free ions also occurs. OBJECTIVE: To quantify calcium loss and improve understanding of calcium homeostasis in CVVHD-F. METHODS: Calcium loss was prospectively quantified from heparinised and citrated circuits in consecutive intensive care patients requiring CVVHD-F. CVVHD-F prescription and anticoagulation choice was by the treating intensivist using commercial solutions (Gambro, Lundia, Sweden). Sample sets comprising arterial, prefilter and postfilter blood and an effluent sample were analysed for ionised total calcium (iCa(2+)) and magnesium levels. Flow rates were then used to calculate calcium flux. Citrate dose (predilution rate) and calcium replacement followed unit protocols to maintain a circuit iCa(2+) concentration of 0.3-0.5 mmol/L and an arterial iCa(2+) concentration of 0.8-1.1 mmol/L. RESULTS: 26 heparinised circuits and 22 citrated circuits in 13 patients were included; 334 sample sets were tested. For target extracorporeal blood flows of 200 mL/min, mean predilution Prismocitrate 10/2 flows were 1660 mL/h, delivering 2.42 mmol citrate per litre of blood. For heparin, mean predilution flows of Hemosol B0 were 2058mL/h. Mean calcium loss was 4.01 mmol/h from citrate anticoagulated circuits versus a gain of 0.24mmol/h from heparinised circuits (P < 0.001). Despite calcium replacement, citrate patients experienced a mean calcium loss of 1.12 mmol/h (SD, 0.70; 95% CI 1.0-1.22mmol/h; P < 0.001). Calculated effective diffusion volume (Q(E)) for calcium was closer to total blood water volume in heparin circuits and closer to plasma water volume in citrate circuits. CONCLUSIONS: Despite supplementation to maintain arterial iCa(2+) levels, citrate anticoagulation results in a net calcium deficit. An equation for estimating required citrate dose may allow revision of citrate dosing protocols.

Influence of insertion site on central venous catheter colonization and bloodstream infection rates.

OBJECTIVE: To compare colonization and catheter-related bloodstream infection (CR-BSI) rates among three insertion sites (subclavian, internal jugular, femoral) used for central venous catheter (CVC) placement. DESIGN: Twenty-four-month prospective study, with relative effects analyzed by Cox proportional hazards regression. SETTING: Eight-bed intensive care unit. PATIENTS: Four hundred and ten critically ill patients requiring CVC placement. MEASUREMENTS AND RESULTS: All short-term multi-lumen CVCs, including antimicrobial-coated devices, were studied with management standardized. Six hundred and five CVCs (4,040 catheter days) were analyzed. Colonization and CR-BSI incidence were, respectively, 15.1 (95% CI 13.5-21.0) and 1.8 (95% CI 1.2-4.2) per 1,000 catheter-days. Colonization was higher at the internal jugular (HR 3.64; 95% CI 1.32-10.00; p=0.01) and femoral (HR 5.15; 95% CI 1.82-14.51; p=0.004) sites than at the subclavian site. The femoral site carried a greater risk of being colonized by non-S. epidermidis species than the subclavian and internal jugular sites combined (HR 4.15; 95% CI 1.79-9.61; p=0.001). CVCs inserted in the Department of Emergency Medicine were more colonized than those inserted in the ICU or operating room (HR 2.66; 95% CI 1.27-5.56; p=0.01), and CVCs were less colonized in females than in males (HR 0.49; 95% CI 0.26-0.89; p=0.02). No difference in CR-BSI rates was noted between the three sites. CONCLUSIONS: Colonization was lowest at the subclavian site. Regional differences exist with respect to type of pathogen isolated. Colonization was influenced by insertion location and gender. The incidence of CR-BSI was not different.