Steroid modulation of cytokine release and desmosine levels in bilateral total knee replacement: a prospective, double-blind, randomized controlled trial.

BACKGROUND: The perioperative inflammatory response as measured by elevated levels of interleukin-6 (IL-6) has been linked to acute respiratory distress syndrome, postoperative confusion, and fever. Because of the extent of surgery,patients undergoing bilateral total knee arthroplasty may be at high risk of complications. We had found a significant decrease in IL-6 in patients having bilateral total knee replacement who received two doses of 100 mg of hydrocortisone eight hours apart; however, by twenty-four hours, IL-6 levels were equal to those in the group that received a placebo. In the present study, we investigated whether the administration of three doses would reduce IL-6 levels at twenty-four hours and affect other outcomes such as desmosine level, a marker of lung injury. METHODS: After institutional review board approval, a total of thirty-four patients (seventeen patients and seventeen control subjects) were enrolled in this double-blind, randomized, placebo-controlled study. Three doses of intravenous hydrocortisone (100 mg) or placebo were given eight hours apart. Urinary desmosine levels were obtained at baseline and at one and three days postoperatively. The level of IL-6 was measured at baseline and at six, ten, twenty-four, and forty-eight hours postoperatively. Pain scores, presence of fever, and functional outcomes were recorded. RESULTS: The level of IL-6 increased in both groups, but was significantly higher in the control group, peaking at twenty-four hours (mean and standard deviation, 623.74 ± 610.35 pg/mL versus 148.13 ± 119.35 pg/mL; p = 0.006). Urinary desmosine levels significantly increased by twenty-four hours in the control group, but remained unchanged in the study group (134.75 ± 67.88 pmol/mg and 79.45 ± 46.30 pmol/mg, respectively; p = 0.006). Pain scores at twenty-four hours were significantly lower in the study group (1.4 ± 0.9 versus 2.4 ± 1.2; p = 0.01) as was the presence of fever (11.8%versus 47.1%; p = 0.03). Range of motion at the knee was significantly greater in the study group (81.6 ± 11.6 versus 70.6 ± 14.0 in the right knee [p = 0.02] and 81.4 ± 11.3 versus 73.4 ± 9.4 in the left knee [p = 0.03]). CONCLUSIONS: Hydrocortisone (100 mg) given over three doses, each eight hours apart, decreased and maintained a lower degree of inflammation with bilateral total knee replacement as measured by IL-6 level. Corticosteroids decreased the prevalence of fever, lowered visual analog pain scores, and improved knee motion. The significantly lower values of desmosine in the study group suggest that this treatment may be protective against lung injury.

Cerebral oximetry desaturation during shoulder surgery performed in a sitting position under regional anesthesia.

PURPOSE: Hypotension in the sitting position may reduce cerebral perfusion and oxygenation. We prospectively determined the incidence of cerebral oximetry (rSO2) desaturation in seated patients undergoing ambulatory shoulder arthroscopy. METHODS: A cohort of 99 patients received regional anesthesia and intravenous sedation, and their blood pressure was recorded every five minutes. Hypotension was defined as the occurrence of any of the following: > 30% decline in mean arterial pressure (MAP), systolic blood pressure < 90 mmHg, or MAP <66 mmHg. Cerebral desaturation was defined as a > 20% decrease in rSO2 from baseline. The association of rSO2 desaturation with potential risk factors was examined by the generalized estimating equation to account for within patient correlation and multiple observations per patient. We fitted desaturation with three models: 1) unadjusted (i.e., hypotension as sole regressor); 2) time-trend adjusted; and 3) baseline-factors adjusted model. RESULTS: Hypotension occurred in 76% of observations (mean duration 4,261 sec), but cerebral desaturation was seen in only 0.77% of observations (mean duration 426 sec). Ninety-nine percent of patients experienced hypotension, but cerebral desaturation occurred in only 10%. By unadjusted modelling, hypotension was associated with cerebral desaturation (odds ratio = 3.21; P = 0.02). Once time-trend adjusted, cerebral desaturation was associated with time from baseline but not with hypotension (P = 0.14). When adjusted for baseline factors, the analysis demonstrated a non-significant association with hypotension (P = 0.34) but a significant association with the presence of risk factors for cerebrovascular disease (P = 0.01). CONCLUSIONS: Despite frequent hypotension in the sitting position, rSO2 desaturation was uncommon during shoulder arthroscopy performed in the sitting position with regional anesthesia.

Stroke, regional anesthesia in the sitting position, and hypotension: a review of 4169 ambulatory surgery patients.

BACKGROUND AND OBJECTIVE: Intraoperative hypotension is used to reduce surgical bleeding. Case reports of stroke after general anesthesia in the sitting position led us to collect data (patient demographics, medical risk factors for stroke, intraoperative hemodynamics) about the incidence of stroke after surgery in the sitting position. METHODS: This study reviewed 4169 (3000 retrospective, 1169 prospective) ambulatory shoulder surgeries in the sitting position. For the prospective cohort, patients were queried postoperatively regarding stroke, with corroboration from 4 databases (anesthesia department quality assurance, hospital case management, state-reportable events, and hospital information system diagnostic code databases). For the retrospective cohort, rate of stroke was determined via the same 4 databases. RESULTS: No patient had a stroke (95% confidence interval, 0%-0.07%). Risk factors for perioperative stroke were present in 40% of patients. Brachial plexus nerve block with intravenous sedation was used for 95.7% (retrospective) and 99.8% (prospective) of the cohorts. Many patients (47%) experienced intraoperative hypotension by at least one definition: 40% (retrospective) and 30% (prospective) had at least a 30% decrease in mean arterial pressure; 27% (retrospective) and 24% (prospective) had a mean pressure less than 66 mm Hg; and 13% (retrospective) and 12% (prospective) had a systolic blood pressure of less than 90 mm Hg. CONCLUSIONS: No strokes were observed in 4169 patients. The estimated upper limit of the 95% confidence interval for stroke after regional anesthesia for shoulder surgery in the seated position is 0.07%, despite frequent incidence of hypotension.

Use of low-dose steroids in decreasing cytokine release during bilateral total knee replacement.

BACKGROUND: Interleukin 6 (IL-6), a marker of inflammation, is one of the major cytokines released during joint replacement. In the orthopedic patient population, high levels have been linked to many adverse effects including acute respiratory distress syndrome, postoperative mental status changes, and fever. We looked to assess the efficacy of low-dose steroids on the postinflammatory response as measured by IL-6 in patients undergoing bilateral total knee replacement (BTKR). The role of steroids has never been evaluated before in that setting. METHODS: Double-blind, randomized, placebo-controlled study of 30 patients undergoing BTKR. The study was powered in order to detect at least a 25% decrease in IL-6 from control. Hydrocortisone (100 mg) or placebo was given at 2 doses 8 hrs apart to the study and control group respectively. Clinical outcome was assessed as well. RESULTS: Levels of IL-6 were 40% lower in the study group by 10 hrs (P = 0.0037) but were similar to the control group at 24 hrs. Greater hemodynamic stability was noted in the study group with fewer episodes of hypotension postoperatively (P = 0.031). Range of motion gained on discharge was also greatest in the study group (P = 0.049). Absence of infection and normal wound healing were noted in all patients. CONCLUSIONS: The use of hydrocortisone significantly decreased the inflammatory response in patients undergoing BTKR as measured by IL-6 production. Further studies looking at clinical implications of such findings in a larger patient population and with a longer course of steroids are warranted.