Extended Perineural Analgesia After Hip and Knee Replacement When Buprenorphine-Clonidine-Dexamethasone Is Added to Bupivacaine: Preliminary Report from a Randomized Clinical Trial.

OBJECTIVE: We tested the hypothesis that buprenorphine-clonidine-dexamethasone (BCD) extends perineural analgesia compared with plain bupivacaine (BPV) nerve blocks used for hip and knee replacement surgery. DESIGN: Prospective, parallel-arms, randomized, double-blind trial. SETTING: A single veterans' hospital. SUBJECTS: Seventy-eight veterans scheduled for total hip or knee replacement with plans for spinal as the primary anesthetic. METHODS: Participants underwent nerve/plexus blocks at L2-L4 and L4-S3 in advance of hip or knee joint replacement surgery. Patients were randomized to receive BPV-BCD or plain BPV in a 4:1 allocation ratio. Patients answered four block duration questions (listed below). Time differences between treatments were analyzed using the t test. RESULTS: Significant (P < 0.001) prolongation of the time parameters was reported by patients after the BPV-BCD blocks (N = 62) vs plain BPV (N = 16). The time until start of postoperative pain was 26 vs 11 hours (mean difference = 15 hours, 95% CI = 8 to 21). The time until no pain relief from the blocks was 32 vs 15 hours (mean difference = 17 hours, 95% CI = 10 to 24). The time until the numbness wore off was 37 vs 21 hours (mean difference = 16 hours, 95% CI = 8 to 23). The time until the worst postoperative pain was 39 vs 20 hours (mean difference = 19 hours, 95% CI = 11 to 27). CONCLUSIONS: BPV-BCD provided 26-39 hours of perineural analgesia in the L2-L4 and L4-S3 nerve distributions after hip/knee replacement surgery, compared with 11-21 hours for plain BPV.

Perioperative clinical utility of myocardial deformation imaging: a narrative review.

Preoperative cardiac function is an important predictor of postoperative outcomes. Patients with heart failure are at higher risk of perioperative morbidity and mortality. Left ventricular ejection fraction, derived by standard echocardiography, is most frequently used to assess cardiac function in the intraoperative and postoperative periods. Myocardial strain analysis, a measurement of myocardial deformation, can provide additional information to left venricular eject fraction estimation. Here, we provide an overview of myocardial strain and different methods used to evaluate strain, including speckle tracking echocardiography. Speckle tracking echocardiography is an imaging modality that can analyse and track small segments of the myocardium, which provides greater detail for assessing global and regional cardiac motion and function. We further review the literature to illustrate the value of speckle tracking echocardiography-derived myocardial strain in describing cardiac function and its association with adverse surgical outcomes in the perioperative period, including low cardiac output states, need for inotropic support, postoperative arrhythmias, subclinical myocardial ischaemia, and length of hospital stay.