Perioperative pain management in fast-track knee arthroplasty

An alternative method for personalized tourniquet pressure in total knee arthroplasty: a prospective randomized and controlled study

Tourniquet use always carries potential risks, which can range from mild transient functional impairments of thigh pain, skin blisters to severe permanent dysfunction of limb paralysis, nerve injuries or compartment syndrome. The ideal method for minimizing intraoperative tourniquet pressure (TP) for reducing postoperative complications remains controversial. In this prospective, randomized and controlled study, we reinvestigated an estimation formula for TP based on thigh circumferences and systolic blood pressure (SBP) with two traditional methods for TP determination in total knee arthroplasty (TKA): SBP plus 100 mmHg and a fixed value of 300 mmHg. TP values and postoperative thigh pain scores were compared among three groups. The intraoperative TP value of the formula-calculated group was lower than that of the traditional groups (14.7 mmHg, P = 0.3475 and 94.7 mmHg, P < 0.0001, respectively), while no differences of hemostatic effect at the surgical fields and wound complications were detected among groups. The thigh pain scores at the tourniquet site decreased gradually over time and the estimation group had the lowest scores at each timepoint after surgery. Estimation method for TP was easy and rapid, without relying on specific equipment. It could provide a practical low TP and comparable hemostatic effect in TKA using an inflating tourniquet.

Effects of intraarticular ketamine combined with periarticular bupivacaine on postoperative pain after arthroscopic meniscectomy

OBJECTIVES

This study aims to evaluate the effects of two different doses of intraarticular ketamine on visual analog scale (VAS) scores at rest and movement, time to first analgesic requirement, and 24-h morphine consumption in patients undergoing arthroscopic meniscectomy as well as to assess the frequency of postoperative nausea&vomiting, respiratory depression, pruritus, urinary retention, and constipation and to compare the time to discharge.

PATIENTS AND METHODS

This prospective randomized double-blind study was performed between August 2013 and August 2014 on 75 patients (32 males, 43 females; mean age 46.7±13 years; range, 18 to 75 years) with American Society of Anesthesiologists scores of I-II scheduled for unilateral meniscectomy. Patients were randomized to receive 0.5 mg.kg^-1 ketamine (group K1), 1 mg.kg^-1 ketamine (group K2) or saline (group S) to a total volume of 20 mL intraarticularly at the end of the surgery. All patients were performed periarticular 10 mL 0.5% bupivacaine infiltration. Visual analog scale at rest and during passive knee movement was used to evaluate pain both preoperatively and at postoperative 0, 30 min, and 1, 2, 4, 6, 12, and 24 h. Time to first analgesic requirement and morphine consumption were recorded.

RESULTS

Visual analog scale scores at rest and during movement at postoperative 0 were significantly reduced in group K2 compared with group S (p<0.05). The first analgesic requirement time was significantly longer in group K1 (76.9±25.2 min) and group K2 (93.4±26.1 min) than group S (29.3±7.1 min). Morphine consumption was lower in group K2 compared to group K1 and group S at postoperative 30 min, and 1 and 2 h. However, 24-h morphine consumption was similar in all groups.

CONCLUSION

Intraarticular injection of 0.5 mg.kg^-1 and 1 mg.kg^-1 ketamine for postoperative pain management provided similar analgesic efficacy. However, high dose ketamine more noticeably decreased opioid requirement in the early postoperative period.