Use of a buprenorphine-based pain management protocol is associated with reduced opioid requirements and pain on swallowing in oral mucositis: a retrospective cohort study.

OBJECTIVE: 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). DESIGN: This is a retrospective cohort study. SETTING: This study was done in a single Quaternary Referral Centre, Haematology Unit. SUBJECTS: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Complete opioid transition to sublingual Buprenorphine after abdominal surgery is associated with significant reductions in opioid requirements, but not reduction in hospital length of stay: a retrospective cohort study.

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.

Hemodynamic Response After Rapid Sequence Induction With Ketamine in Out-of-Hospital Patients at Risk of Shock as Defined by the Shock Index.

STUDY OBJECTIVE: Ketamine is considered a stable induction agent for rapid sequence induction; however, hypotension rates up to 24% are reported. The shock index (shock index=pulse rate/systolic blood pressure [SBP]) may identify patients at risk of adverse hemodynamic change. We investigate whether SBP and pulse rate response to ketamine induction differ when patients are classified as being at risk of shock by their shock index. METHODS: We conducted a prospective observational study of electronically collected vital sign data from patients undergoing rapid sequence induction with ketamine. Patients were grouped into low shock index (shock index <0.9) or high shock index (shock index ≥0.9) preinduction. Pulse rate and SBP were compared between 3 minutes preinduction and for 3 measurements postinduction (3-minute intervals) by repeated-measures ANOVA. Proportions of patients developing hypotension or hypertension are also reported. RESULTS: One hundred twelve patients were enrolled (81 low shock index, 31 high shock index). Low shock index patients had increased SBP after induction (16 mm Hg; 95% confidence interval [CI] 11 to 21 mm Hg), whereas high shock index patients did not (2 mm Hg; 95% CI -4 to 7 mm Hg). Pulse rate in low shock index patients increased after induction (20 beats/min; 95% CI 16 to 25 beats/min) and remained elevated, whereas in high shock index patients a difference occurred at the second postinduction measurement only (15 beats/min; 95% CI 11 to 18 beats/min). More high shock index patients became hypotensive (26%; 95% CI 12% to 45%) than low shock index ones (2%; 95% CI 0% to 9%), whereas more low shock index patients became hypertensive (40%; 95% CI 29% to 51%) than high shock index ones (13%; 95% CI 4% to 30%). CONCLUSION: After ketamine induction, high shock index patients exhibited blunted hypertensive responses and more frequent hypotension, whereas low shock index patients had sustained increases in pulse rate and SBP.

Peri-OPerative Pain Management, Education & De-escalation (POPPMED), a novel anaesthesiologist-led program, significantly reduces acute and long-term postoperative opioid requirements: a retrospective cohort study.

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.

Differential regulation of L1 and L2 beta-lactamase expression in Stenotrophomonas maltophilia.

It has been reported that Stenotrophomonas maltophilia L1 and L2 beta-lactamase expression is coordinated. We have isolated S. maltophilia mutants where (i) L1 is constitutively hyper-expressed and L2 is inducible; (ii) L2 is hyper-expressed and L1 is inducible; and (iii) L1 and L2 are constitutively hyper-expressed. The frequency of isolating type 1 and 2 mutants is c. 10(-7), indicating that promoter mutations are probably not involved and providing strong evidence that L1 and L2 expression is not, after all, coordinated. The frequency of isolating type 3 mutants is c. 10(-9), however, implying that there is a significant overlap between the regulatory mechanisms.