Importance Liquid-stored platelets have a shelf-life of 5 to 7 days, limiting availability and resulting in wastage. Objective To assess the effectiveness and safety of dimethyl sulfoxide–cryopreserved platelets, which have a shelf-life of 2 years, as a treatment for cardiac surgery bleeding. Design, Setting, and Participants The Cryopreserved vs Liquid Platelets II (CLIP-II) trial was a multicenter, randomized, double-blind, parallel-group noninferiority trial, which enrolled patients between August 2021 and April 2024 at 11 Australian tertiary hospitals, with follow-up completed in July 2024. Patients at high risk of platelet transfusion were eligible. Patients were excluded if they had a history of deep vein thrombosis or pulmonary embolism, were coagulopathic, or were females aged 18 to 55 years who were rhesus D (RhD) negative or of unknown RhD status. Of 879 patients meeting inclusion criteria, 182 were excluded and 285 did not consent, leaving 412. Of these, 388 were randomized and 202 received study platelets. Interventions Patients received up to 3 units of either group O cryopreserved platelets or conventional liquid-stored platelets, commencing intraoperatively or in the first 24 postoperative hours. Main Outcomes and Measures The primary outcome was postsurgical chest drain bleeding within the first 24 hours following intensive care unit admission. Noninferiority was defined prospectively as less than 20% greater bleeding in this period. Five secondary and 42 tertiary outcomes were defined a priori. Results Of the 202 transfused patients (mean [SD] age, 64.4 [13] years; 75.7% male), 61 (30.2%) underwent nonelective surgery. The primary outcome did not differ between groups (605 mL in cryopreserved platelet group vs 535 mL in liquid-stored platelet group; ratio of geometric means [cryopreserved to liquid ratio], 1.13 [95% CI, 0.96-1.34]; P = .07). As the confidence interval includes bleeding exceeding the noninferiority margin, noninferiority was not established. Cryopreserved platelet transfusion was associated with higher intraoperative and total perioperative blood loss (ratio of geometric means [cryopreserved to liquid ratio], 1.42 [95% CI, 1.12-1.80]; 1.31 [95% CI, 1.07-1.60], respectively), and increased red cell, plasma, and cryoprecipitate transfusion. While there were no differences in the incidence of prespecified adverse events, patients receiving cryopreserved platelets experienced longer times to extubation and intensive care unit/hospital discharge (median [IQR] duration of ventilation, 25.5 hours [16.1-77.3] vs 23.6 hours [13.1-52.8]; median [IQR] intensive care unit length of stay, 3.8 days [2.0-6.0] vs 3.0 days [1.9-4.9]; median hospital length of stay, 10.9 days [7.87-17.0] vs 9.1 [6.9-14.9]). Conclusions and Relevance Cryopreserved platelets did not meet the predefined threshold for noninferiority in hemostatic effectiveness at 24 hours after ICU admission. Additional predefined end points consistently indicated diminished hemostatic effectiveness, although prespecified adverse events were comparable. Trial Registration ClinicalTrials.gov Identifier: NCT03991481

In this issue of Heart, Lung and Circulation, Rajagopalan et al. provide evidence that a lower pre-operative mean perfusion pressure was associated with decreased post-operative survival in patients undergoing heart transplantation [1]. Further, their study carefully teased out the contributions of high venous pressure, arterial elastance (Ea) and body surface area (BSA) on the relationship between mean perfusion pressure and survival. This work provides further evidence for individualising therapies—suggesting a need to aim for higher mean perfusion pressure, particularly in those with pre-existing high venous pressure and high BSA, and prudence in quantifying Ea to avoid excessively low Ea.

PURPOSE:This prospective observational study aimed to establish the frequency of postoperative nocturnal respiratory abnormalities among patients undergoing major surgery who received ward-level care. These abnormalities may have implications for postoperative pulmonary complications (PPCs). METHODS:Eligible patients underwent blinded noninvasive continuous capnography with pulse oximetry using the Capnostream™ 20p monitor over the first postoperative night. All patients received oxygen supplementation and patient-controlled opioid analgesia. The primary outcome was the number of prolonged apnea events (PAEs), defined as end-tidal carbon dioxide (EtCO2) ≤5 mmHg for 30-120 seconds or EtCO2 ≤5 mmHg for >120 seconds with oxygen saturation (SpO2) <85%. Secondary outcomes were the proportion of recorded time that physiological indices were aberrant, including the apnea index (AI), oxygen desaturation index (ODI), integrated pulmonary index (IPI), and SpO2. Exploratory analysis was conducted to assess the associations between PAEs, PPCs, and pre-defined factors. RESULTS:Among 125 patients who had sufficient data for analysis, a total of 1800 PAEs occurred in 67 (53.4%) patients. The highest quartile accounted for 89.1% of all events. Amongst patients who experienced any PAEs, the median (IQR) number of PAE/patient was four (2-12). As proportions of recorded time (median (IQR)), AI, ODI, and IPI were aberrant for 12.4% (0-43.2%), 19.1% (2.0-57.1%), and 11.5% (3.1-33.3%) respectively. Only age, ARISCAT, and opioid consumption/kg were associated with PPCs. CONCLUSIONS:PAE and aberrant indices were frequently detected on the first postoperative night. However, they did not correlate with PPCs. Future research should investigate the significance of detected aberrations.

Abstract Background We recently reported the results for a large randomized controlled trial of low tidal volume ventilation (LTVV) versus conventional tidal volume (CTVV) during major surgery when positive end expiratory pressure (PEEP) was equal between groups. We found no difference in postoperative pulmonary complications (PPCs) in patients who received LTVV. However, in the subgroup of patients undergoing laparoscopic surgery, LTVV was associated with a numerically lower rate of PPCs after surgery. We aimed to further assess the relationship between LTVV versus CTVV during laparoscopic surgery. Methods We conducted a post-hoc analysis of this pre-specified subgroup. All patients received volume-controlled ventilation with an applied PEEP of 5 cmH2O and either LTVV (6 mL/kg predicted body weight [PBW]) or CTVV (10 mL/kg PBW). The primary outcome was the incidence of a composite of PPCs within seven days. Results Three hundred twenty-eight patients (27.2%) underwent laparoscopic surgeries, with 158 (48.2%) randomised to LTVV. Fifty two of 157 patients (33.1%) assigned to LTVV and 72 of 169 (42.6%) assigned to conventional tidal volume developed PPCs within 7 days (unadjusted absolute difference, − 9.48 [95% CI, − 19.86 to 1.05]; p = 0.076). After adjusting for pre-specified confounders, the LTVV group had a lower incidence of the primary outcome than patients receiving CTVV (adjusted absolute difference, − 10.36 [95% CI, − 20.52 to − 0.20]; p = 0.046). Conclusion In this post-hoc analysis of a large, randomised trial of LTVV we found that during laparoscopic surgeries, LTVV was associated with a significantly reduced PPCs compared to CTVV when PEEP was applied equally between both groups. Trial registration Australian and New Zealand Clinical Trials Registry no: 12614000790640.

INTRODUCTION:The optimal analgesic modality for patients undergoing hepato-pancreato-biliary (HPB) surgery remains unknown. The analgesic effects of a multimodal intrathecal analgesia (MITA) technique of intrathecal morphine (ITM) in combination with clonidine and bupivacaine compared to ITM alone have not been investigated in these patients.METHODS:We performed a multicenter retrospective study of patients undergoing complex HPB surgery who received ITM, bupivacaine, and clonidine (MITA group) or ITM-only (ITM group) as part of their perioperative analgesia strategy. The primary outcome was the unadjusted oral morphine equivalent daily dose (oMEDD) in milligrams on postoperative day 1. After adjusting for age, body mass index, hospital allocation, type of surgery, operation length, and intraoperative opioid use, postoperative oMEDD use was investigated using a bootstrapped quantile regression model. Other prespecified outcomes included postoperative pain scores, opioid-related adverse events, major complications, and length of hospital stay.RESULTS:In total, 118 patients received MITA and 155 patients received ITM-only. The median (IQR) cumulative oMEDD use on postoperative day 1 was 20.5 mg (8.6:31.0) in the MITA group and 52.1 mg (18.0:107.0) in the ITM group (P < 0.001). There was a variation in the magnitude of the difference in oMEDD use between the groups for different quartiles. For the MITA group, on postoperative day 1, patients in the 25th percentile required 14.0 mg less oMEDD (95% CI: -25.9 to -2.2; P = 0.025), patients in the 50th percentile required 27.8 mg less oMEDD (95% CI: -49.7 to -6.0; P = 0.005), and patients in the 75th percentile required 38.7 mg less oMEDD (95% CI: -72.2 to -5.1; P = 0.041) compared to patients in the same percentile of the ITM group. Patients in the MITA group had significantly lower pain scores in the postoperative recovery unit and on postoperative days 1 to 3. The incidence of postoperative respiratory depression was low (<1.5%) and similar between groups. Patients in the MITA group had a significantly higher incidence of postoperative hypotension requiring vasopressor support. However, no significant differences were observed in major postoperative complications, or the length of hospital stay.CONCLUSION:In patients undergoing complex HPB surgery, the use of MITA, consisting of ITM in combination with intrathecal clonidine and bupivacaine, was associated with reduced postoperative opioid use and resulted in superior postoperative analgesia without risk of respiratory depression when compared to patients who received ITM alone. A randomized prospective clinical trial investigating these two intrathecal analgesic techniques is justified.

BACKGROUND Studies in critically ill patients suggest a relationship between mechanical power (an index of the energy delivered by the ventilator, which includes driving pressure, respiratory rate, tidal volume and inspiratory pressure) and complications. OBJECTIVE We aimed to assess the association between intra-operative mechanical power and postoperative pulmonary complications (PPCs). DESIGN Post hoc analysis of a large randomised clinical trial. SETTING University-affiliated academic tertiary hospital in Melbourne, Australia, from February 2015 to February 2019. PATIENTS Adult patients undergoing major noncardiothoracic, nonintracranial surgery. INTERVENTION Dynamic mechanical power was calculated using the power equation adjusted by the respiratory system compliance (C-RS). Multivariable models were used to assess the independent association between mechanical power and outcomes. MAIN OUTCOME MEASURES The primary outcome was the incidence of PPCs within the first seven postoperative days. The secondary outcome was the incidence of acute respiratory failure. RESULTS We studied 1156 patients (median age [IQR]: 64 [55 to 72] years, 59.5% men). Median mechanical power adjusted by C-RS was 0.32 [0.22 to 0.51] (J min(-1))/(ml cmH(2)O(-1)). A higher mechanical power was also independently associated with increased risk of PPCs [odds ratio (OR 1.34, 95% CI, 1.17 to 1.52); P < 0.001) and acute respiratory failure (OR 1.40, 95% CI, 1.21 to 1.61; P < 0.001). CONCLUSION In patients receiving ventilation during major noncardiothoracic, nonintracranial surgery, exposure to a higher mechanical power was independently associated with an increased risk of PPCs and acute respiratory failure.

Acute kidney injury (AKI) is common in the critically ill. Inadequate renal medullary tissue oxygenation has been linked to its pathogenesis. Moreover, renal medullary tissue hypoxia can be detected before biochemical evidence of AKI in large mammalian models of critical illness. This justifies medullary hypoxia as a pathophysiological biomarker for early detection of impending AKI, thereby providing an opportunity to avert its evolution. Evidence from both animal and human studies supports the view that non-invasively measured bladder urinary oxygen tension (PuO2) can provide a reliable estimate of renal medullary tissue oxygen tension (tPO2), which can only be measured invasively. Furthermore, therapies that modify medullary tPO2 produce corresponding changes in bladder PuO2. Clinical studies have shown that bladder PuO2 correlates with cardiac output, and that it increases in response to elevated cardiopulmonary bypass (CPB) flow and mean arterial pressure. Clinical observational studies in patients undergoing cardiac surgery involving CPB have shown that bladder PuO2 has prognostic value for subsequent AKI. Thus, continuous bladder PuO2 holds promise as a new clinical tool for monitoring the adequacy of renal medullary oxygenation, with its implications for the recognition and prevention of medullary hypoxia and thus AKI.

Objectives Poor medullary oxygenation is implicated in the evolution of acute kidney injury. The authors sought to determine if increasing systemic flow and mean arterial pressure could improve urine oxygen tension (PuO2) measured in the bladder, a surrogate of kidney medullary oxygenation, in patients undergoing on-pump cardiac surgery. Design Randomized crossover study. Setting University-affiliated hospital. Participants Twenty adult patients undergoing cardiopulmonary bypass (CPB) with expected cross-clamp time of >60 minutes and estimated glomerular filtration rate of >30 mL/min/1.73m2. Interventions Sequential 20-minute periods of 2 interventions: Intervention H ("High") or Intervention N ("Normal"). The order of interventions was determined by randomization. Intervention H: targeted CPB flow 3.0 L/min/m2 and mean arterial pressure (MAP) 80 mmHg. Intervention N: targeted CPB flow 2.4 L/min/m2 and MAP 65 mmHg. Measurements and Main Results PuO2 was measured by an oxygen sensor introduced into the bladder via a urinary catheter. Clear separation was achieved in CPB flow and MAP between intervention periods (p < 0.001 for group-time interaction). PuO2 during Intervention H was higher than during Intervention N (p < 0.001 for group-time interaction). After 17 minutes, PuO2 was statistically higher in Intervention H at each time point. There were no differences in markers of hemolysis between interventions. Conclusions PuO2 was higher when systemic flow and MAP were increased during CPB. These findings suggest that PuO2 is responsive to changes in hemodynamics and that higher flow and pressure may improve medullary oxygenation.

Background: The use of sublingual buprenorphine (SLBup) for acute pain after major abdominal surgery may offer the potential advantages of unique analgesic properties and more reliable absorption during resolving ileus. We hypothesized that complete opioid transition to SLBup rather than oral oxycodone (OOxy) in the early postoperative period after major abdominal surgery would reduce hospital length of stay, and acute pain and total OMEDD (Oral Morphine Equivalent Daily Dose) requirements in the first 24 h from post-parenteral opioid transition. Methods: We reviewed 146 patients who had undergone elective and emergency abdominal surgery under our quaternary referral centre's Upper Gastro-Intestinal and Colo-Rectal Surgical Units 6 months before and after the introduction of complete postoperative transition to sublingual buprenorphine, rather than oral oxycodone, in July 2017. Our primary endpoint was 24-hourly post-transition OMEDDs; secondary endpoints were 24-hourly post-transition Mean NRS-11 pain scores on movement (POM) and length of hospital stay (LOS). Univariate analysis and linear multivariate regression analyses were used to quantify effect size and identify surgical, patient & other analgesic factors associated with these outcome measures. Results: Patients transitioning to SLBup had reduced 24-hourly post-transition OMEDD requirements on postoperative day 2 (POD) (26 mg less, p = 0.04) and NRS-11 POM at POD1 (0.7 NRS-11 units less, p = 0.01). When adjusting for patient, surgical and special analgesic factors, SLBup was associated with a similar reduction in OMEDDs (Unstandardised beta-coefficient -26 mg, p = 0.0001), but not NRS-11 POM (p = 0.47) or hospital LOS (p = 0.16). Conclusions: Our change of practice from use of OOxy to SLBup as primary transition opioid from patient-controlled analgesia delivered full opioid agonists was associated with a clinically significant decrease in 24-hourly post-parenteral opioid transition OMEDDs and improved NRS-11 POM, but without an association with hospital LOS after major abdominal surgery. Further prospective randomized work is required to confirm these observed associations and impact on other important patient-centred outcomes.

Transfusion Requirements in Cardiac Surgery III (TRICS III), a multi‐center randomized controlled trial, demonstrated clinical non‐inferiority for restrictive versus liberal RBC transfusion for patients undergoing cardiac surgery. However, it is uncertain if transfusion strategy affects long‐term health‐related quality of life (HRQOL).

Introduction:The opioid tolerant patient requiring surgery is highly likely to be discharged on high Oral Morphine Equivalent Daily Dosages (OMEDDs), with concomitant risk of increased morbidity and mortality. Objectives:We proposed that a single anaesthesiologist-led POPPMED (Peri-Operative Pain Management, Education & De-escalation) service could reduce both short and long-term postoperative patient OMEDDs. Methods:From April 2017, our anaesthesiologist-led POPPMED service, engaged 102 perioperative patients treated with >50mg preoperative OMEDDs. We utilized behavioural interventions; acute opioid reduction and/ or rotation; and regional, multimodal and ketamine analgesia to achieve lowest possible hospital discharge and long term OMEDDs. Results:Patients' preoperative OMEDDs were [median (IQR): 115mg (114mg)], and were representative of an older [age 62 (15) years], high-risk [89% ASA status 3 or 4] patient population. 46% of patients received an acute opioid rotation; 70% received ketamine infusions; and 44% regional analgesia. OMEDDs on discharge [-25mg (82mg), p=0.003] and at 6-12 months [-55mg (105mg ), p<0.0001] were significantly reduced; 84% and 87% of patients achieved OMEDD reduction on discharge and at 6-12 months. Patients with >90mg preoperative OMEDDs achieved greater reductions [discharge: 71% of patients, -52 mg (118 mg) p<0.0001; 6-12 months: 90% of patients, -90mg (115mg), p<0.0001]. On comparison with a pre-POPPMED surgical cohort, Postoperative Day 1-3 11-point Numerical Rating Scale (NRS-11) area under the curve (AUC) measurements at rest and on movement were not significantly different (largest NRS-11:hours AUC difference [median(IQR)] 22 [13], p= 0.24). Hospital length of stay was variably increased. Conclusions:POPPMED achieved sustained OMEDD reductions safely in an older, high-risk opioid tolerant population, with analgesia comparable to a non-POPPMED cohort, and surgery specific effects on length of stay.

The aim of this study is to ascertain the analgesic efficacy and total oral morphine equivalent daily dose (OMEDD) effect of a buprenorphine-based analgesic protocol in the treatment of severe Oral Mucositis (OM). This is a retrospective cohort study. This study was done in a single Quaternary Referral Centre, Haematology Unit. Fifty-four stem cell transplant patients suffering at least grade 3 oral mucositis (OM), 24 prior to [Pr-I] and 30 subsequent to [Po-I] a buprenorphine-based OM analgesic protocol. We analysed data from the above subjects with the primary outcome measure of difference in total OMEDDs from all opioid types and administration routes, and secondary outcome measures of area under the curve (AUC) of 11-point Numerical Rating Scale (NRS-11) pain assessments, sedation scores and respiratory rate. Post-protocol patients’ total OMEDD requirements were significantly reduced [Pr-I: 1961 (1365)mg; Po-I: 928 (625)mg, p = 0.02], as were total NRS-11:hours AUC on swallowing [Pr-I: 54(24) score-hours; Po-I: 41(18) score-hours, p < 0.001]. There were no significant differences in objective measures of OM severity between groups (Number of Grade 3 or 4 OM severity assessments [mean (SD)] Pr-I: 5 (6.2); Po-I: 7 (5.1) or number of days Neutrophil count 0.0 or 0.1 × 109/L; Pr-I: 13 (5.4); Po-I: 15 (4.7)). 5 Pr-I and 4 Po-I patients required ketamine infusions, with 1 Pr-I patient also requiring IV lignocaine. Use of Buprenorphine via transdermal, sublingual and intravenous Patient Controlled Analgesia (PCA) delivery as part of an analgesic protocol for severe post stem cell transplant oral mucositis in adult patients appears to significantly reduce opioid requirements and pain on swallowing. Further randomised prospective work is required to confirm these associations.

Abstract Background Low tidal volume (VT) ventilation and its associated increase in arterial carbon dioxide (PaCO2) may affect postoperative neurologic function. We aimed to test the hypothesis that intraoperative low VT ventilation affect the incidence of postoperative ICD-10 coded delirium and/or the need for antipsychotic medications. Methods This is a post-hoc analysis of a large randomized controlled trial evaluating low vs. conventional VT ventilation during major non-cardiothoracic, non-intracranial surgery. The primary outcome was the incidence of ICD-10 delirium and/or the use of antipsychotic medications during hospital stay, and the absolute difference with its 95% confidence interval (CI) was calculated. Results We studied 1206 patients (median age of 64 [55–72] years, 59.0% males, median ARISCAT of 26 [19–37], and 47.6% of ASA 3). ICD-10 coded delirium and /or antipsychotic medication use was diagnosed in 11.2% with similar incidence between low and conventional VT ventilation (11.1% vs. 11.3%; absolute difference, -0.24 [95%CI, -3.82 to 3.32]; p = 0.894). There was no interaction between allocation group and type of surgery. Conclusion In adult patients undergoing major surgery, low VT ventilation was not associated with increased risk of ICD-10 delirium and/or the use of antipsychotic medications during hospital stay. Trial registration ANZCTR Identifier: ACTRN12614000790640.

Clinicians may wish to assess differences in diaphragmatic excursion between the right and left lung at the point of care, in order to exclude diaphragmatic pathology (e.g. phrenic nerve palsy), particularly if a chest X-ray is not available. We conducted an exploratory study comparing the accuracy of lung auscultation against lung ultrasound for point-of-care assessment of the extent of basal lung excursion during maximal inspiration (Austin Human Research Ethics Committee approval LNR/21/Austin/19). A height difference of more than one intercostal space (ICS) between diaphragmatic domes during maximal inspiration on chest X-ray is a commonly used ‘rule of thumb’ suggesting reduced basal lung ventilation on the affected side. 1 We compared the most caudad point of audible breath sounds by stethoscope auscultation to the most caudad point of visible ‘sliding lung’ sign using B-mode ultrasound (US) at the bases of both lungs on 25 healthy consenting volunteers at maximal inspiration, along bilateral parallel lines drawn on the skin at 5 cm from the line of the spinous processes (Figure 1). This most caudad point of visible ‘sliding lung’ sign is known as the ‘lung point’ when used to diagnose pneumothorax, defining an interface at which mobile apposition of the parietal and visceral pleura is lost. US was considered the reference standard for data analysis. Anecdotally, we had previously observed that US detected reduced basal lung expansion by loss of lung point descent and a more cranial lung point at maximal inspiration in two patients scanned pre and post interscalene block. To identify a reference height difference comparable to measurements using a chest X-ray, we measured the perpendicular

Inadequate analgesia after thoracic surgery has been associated with postoperative pulmonary complications and prolonged hospital stay.[1][1] Regional anesthesia provides effective opioid-sparing analgesia and has been recommended during enhanced recovery after lung surgery.[2][2] Surgically placed

To characterize the association between diabetes and transfusion and clinical outcomes in cardiac surgery, and to evaluate whether restrictive transfusion thresholds are harmful in these patients.

# 01. Design and validation of a unique endoscopy simulator using a commercial video game {#article-title-2} Procedural simulation has been shown to enhance early endoscopy training. In this proof of concept study, we aimed to show that a first-person shooter (FPS) video game with a novel in-house

Acute Kidney Injury (AKI) is one of the most frequent adverse consequences of cardiopulmonary bypass (CPB). Mean Arterial Pressure over time has been previously described by our group as a contributor. Other mechanisms and risk factors may exacerbate the risk. We used an artificial intelligence (AI) based approach to build a predictive model.