The Effect of Regional Analgesia on Vascular Tone in Hip Arthroplasty Patients

Background: While it is assumed that neuraxial analgesia and pain management may beneficially influence perioperative hemodynamics, few studies provided data quantifying such effects and none have assessed the potential contribution of the addition of a nerve block. Questions/purposes: This clinical trial compared the visual analog scale (VAS) scores and measurement of arterial tone using augmentation index of patients who received combined spinal-epidural (CSE) only to patients who received both CSE and lumbar plexus block. Methods: After obtaining written consent, 92 patients undergoing total hip arthroplasty were randomized to receive either CSE or CSE with lumbar plexus block (LPB). Perioperative pain and arterial tone were measured using VAS scores and augmentation index (AI) respectively, at baseline and at various times postoperatively. Results: After the exclusion of 2 patients, 44 patients received CSE alone and 46 patients received CSE and LPB. Patient demographics and perioperative characteristics were similar in both groups. AI continuously decreased after placement of a CSE with or without LBP, beyond full resolution of neuraxial and peripheral blockade. Although the LPB group demonstrated a statistically significant reduction of VAS pain scores in the postanesthesia care unit (PACU; P \u3c 0.05), overall, the addition of a LPB did not significantly reduce the AI when compared to the control group. Conclusion: The addition of a LPB provided better pain control in the PACU but did not reduce the AI, compared to the control group. We conclude that the addition of a LPB may have limited ability to affect arterial tone in the presence of a continuous infusion of epidural analgesics. In summary, the addition of a LPB in patients undergoing total hip arthroplasty is clinically effective and provided better pain control, especially in the immediate postoperative period. The continuous decrease on the AI in both groups beyond the full resolution of the neuroaxial and LPB will require further studies

Microvascular response to transfusion in elective spine surgery

AIM: To investigate the microvascular (skeletal muscle tissue oxygenation; SmO2) response to transfusion in patients undergoing elective complex spine surgery. METHODS: After IRB approval and written informed consent, 20 patients aged 18 to 85 years of age undergoing \u3e 3 level anterior and posterior spine fusion surgery were enrolled in the study. Patients were followed throughout the operative procedure, and for 12 h postoperatively. In addition to standard American Society of Anesthesiologists monitors, invasive measurements including central venous pressure, continual analysis of stroke volume (SV), cardiac output (CO), cardiac index (CI), and stroke volume variability (SVV) was performed. To measure skeletal muscle oxygen saturation (SmO2) during the study period, a non-invasive adhesive skin sensor based on Near Infrared Spectroscopy was placed over the deltoid muscle for continuous recording of optical spectra. All administration of fluids and blood products followed standard procedures at the Hospital for Special Surgery, without deviation from usual standards of care at the discretion of the Attending Anesthesiologist based on individual patient comorbidities, hemodynamic status, and laboratory data. Time stamps were collected for administration of colloids and blood products, to allow for analysis of SmO2 immediately before, during, and after administration of these fluids, and to allow for analysis of hemodynamic data around the same time points. Hemodynamic and oxygenation variables were collected continuously throughout the surgery, including heart rate, blood pressure, mean arterial pressure, SV, CO, CI, SVV, and SmO2. Bivariate analyses were conducted to examine the potential associations between the outcome of interest, SmO2, and each hemodynamic parameter measured using Pearson\u27s correlation coefficient, both for the overall cohort and within-patients individually. The association between receipt of packed red blood cells and SmO2 was performed by running an interrupted time series model, with SmO2 as our outcome, controlling for the amount of time spent in surgery before and after receipt of PRBC and for the inherent correlation between observations. Our model was fit using PROC AUTOREG in SAS version 9.2. All other analyses were also conducted in SAS version 9.2 (SAS Institute Inc., Cary, NC, United States). RESULTS: Pearson correlation coefficients varied widely between SmO2 and each hemodynamic parameter examined. The strongest positive correlations existed between ScvO2 (P = 0.41) and SV (P = 0.31) and SmO2; the strongest negative correlations were seen between albumin (P = -0.43) and cell saver (P = -0.37) and SmO2. Correlations for other laboratory parameters studied were weak and only based on a few observations. In the final model we found a small, but significant increase in SmO2 at the time of PRBC administration by 1.29 units (P = 0.0002). SmO2 values did not change over time prior to PRBC administration (P = 0.6658) but following PRBC administration, SmO2 values declined significantly by 0.015 units (P \u3c 0.0001). CONCLUSION: Intra-operative measurement of SmO2 during large volume, yet controlled hemorrhage, does not show a statistically significant correlation with either invasive hemodynamic, or laboratory parameters in patients undergoing elective complex spine surgery

Blood Transfusions in Total Hip and Knee Arthroplasty: An Analysis of Outcomes

Background. Various studies have raised concern of worse outcomes in patients receiving blood transfusions perioperatively compared to those who do not. In this study we attempted to determine the proportion of perioperative complications in the orthopedic population attributable to the use of a blood transfusion. Methods. Data from 400 hospitals in the United States were used to identify patients undergoing total hip or knee arthroplasty (THA and TKA) from 2006 to 2010. Patient and health care demographics, as well as comorbidities and perioperative outcomes were compared. Multivariable logistic regression models were fitted to determine associations between transfusion, age, and comorbidities and various perioperative outcomes. Population attributable fraction (PAF) was determined to measure the proportion of outcome attributable to transfusion and other risk factors. Results. Of 530,089 patients, 18.93% received a blood transfusion during their hospitalization. Patients requiring blood transfusion were significantly older and showed a higher comorbidity burden. In addition, these patients had significantly higher rates of major complications and a longer length of hospitalization. The logistic regression models showed that transfused patients were more likely to have adverse health outcomes than nontransfused patients. However, patients who were older or had preexisting diseases carried a higher risk than use of a transfusion for these outcomes. The need for a blood transfusion explained 9.51% (95% CI 9.12–9.90) of all major complications. Conclusions. Advanced age and high comorbidity may be responsible for a higher proportion of adverse outcomes in THA and TKA patients than blood transfusions

Patient, Surgery, and Hospital Related Risk Factors for Surgical Site Infections following Total Hip Arthroplasty

Surgical site infections (SSI) following total hip arthroplasty (THA) have a significantly adverse impact on patient outcomes and pose a great challenge to the treating surgeon. Therefore, timely recognition of those patients at risk for this complication is very important, as it allows for adopting measures to reduce this risk. This review discusses literature reported risk factors for SSI after THA. These can be classified into patient-related factors (age, gender, obesity, comorbidities, history of infection, primary diagnosis, and socioeconomic profile), surgery-related factors (allogeneic blood transfusion, DVT prophylaxis and coagulopathy, duration of surgery, antibiotic prophylaxis, bearing surface and fixation, bilateral procedures, NNIS index score, and anesthesia type), and hospital-related factors (duration of hospitalization, institution and surgeon volume, and admission from a healthcare facility). All these factors are discussed with respect to potential measures that can be taken to reduce their effect and consequently the overall risk for infection

Peripheral Regional Anesthesia Using Local Anesthetics: Old Wine in New Bottles?

During the past decade, numerous efforts were undertaken aiming at prolonging the analgesic effect of regional anesthesia. With the development of extended-release formulations and enhanced selectivity for nociceptive sensory neurons, a very promising contribution to the development of pain medications has been achieved. At present, liposomal bupivacaine is the most popular, non-opioid, controlled drug delivery system, but its duration of action, which is still controversially discussed, and its expensiveness have decreased initial enthusiasm. Continuous techniques can be seen as an elegant alternative for providing a prolonged duration of analgesia, but for logistic or anatomical reasons, they are not always the best choice. Therefore, focus has been directed towards the perineural and/or intravenous addition of old and established substances. As for perineural application, most of these so-called ‘adjuvants’ are used outside their indication, and their pharmacological efficacy is often not or only poorly understood. This review aims to summarize the recent developments for prolonging the duration of regional anesthesia. It will also discuss the potential harmful interactions and side effects of frequently used analgesic mixtures

The impact of PECS II blockade in patients undergoing minimally invasive cardiac surgery—a prospective, randomized, controlled, and triple-blinded trial

Abstract Background Classic neuraxial techniques, such as thoracic epidural anesthesia, or alternative approaches like the paravertebral block, are not indicated in cardiac surgery due to increased bleeding risk. To provide satisfactory analgesia without the need for excessive opioid use, novel ultrasound techniques gained popularity and are of growing interest. The pectoralis nerve block II (PECS II) has been shown to provide good postoperative analgesia in modified radical mastectomy and might also be suitable for minimally invasive cardiac surgery. Methods In a single center, prospective, triple-blinded, two-group randomized trial, 60 patients undergoing elective, unilateral minimal invasive cardiac surgery will be randomized to receive a PECS II with 30 ml of ropivacaine 0.5% (intervention group) or sodium chloride 0.9% (placebo group). The primary outcome parameter is the overall opioid demand given as intravenous morphine milligram equivalents (MME) during the first 24 h after extubation. Secondary endpoints are the visual analog scale (VAS) 2, 4, 6, 8, 12, and 24 h after extubation, the Overall Benefit of Analgesia Score (OBAS) after 24 h, the interval until extubation, and intensive care unit (ICU) discharge within 24 h, as well as the length of hospital stay (LOS). Discussion This prospective randomized, controlled, and triple-blinded trial aims to assess if a PECS II with ropivacaine 0.5% helps to decrease the opioid demand in the first 24 h and increases postoperative pain control after minimally invasive cardiac surgery. Trial registration www.clinicaltrialsregister.eu ; EudraCT Nr: 2021–005452-11; Lukas Gasteiger MD, November 18, 2021

Critical care in patients undergoing lumbar spine fusion: a population-based study

BACKGROUND: Data on the utilization of critical care services (CCSs) among patients who underwent spine fusion are rare. Given the increasing popularity of this procedure, information regarding demographics and risk factors for the use of these advanced services is needed in order to appropriately allocate resources, educate clinical staff, and identify targets for future research. METHODS: We analyzed hospital discharge data of patients who underwent lumbar spine fusion in approximately 400 US hospitals between 2006 and 2010. Patient, procedure, and health care system-related demographics for those requiring CCS were compared to those who did not. Outcomes such as mortality, complications, disposition status, and hospital charges were compared among groups and risk factors for the utilization of CCS identified. RESULTS: A total of 95 434 entries of patients who underwent posterior lumbar spine fusion surgery between 2006 and 2010 were identified. Approximately 10% of the patients required CCS. On average, patients requiring CCS were older and had a higher comorbidity burden, developed more complications, had longer hospital stays and higher costs, and were less likely to be discharged home compared to non-CCS patients. Risk factors with increased odds for requiring CCS included advanced age, increasing comorbidity burden, increasing surgical invasiveness, and presence of postoperative complications, especially pulmonary. CONCLUSIONS: Approximately, 10% of the patients undergoing lumbar spine surgery require CCS. Utilizing the present data, critical care physicians and administrators can identify patients at risk, educate clinical staff, identify targets for intervention, and allocate resources to meet the needs of this particular patient population

Blood Transfusions May Have Limited Effect on Muscle Oxygenation After Total Knee Arthroplasty

BACKGROUND: Traditionally, blood transfusions in the perioperative setting are used to maintain adequate delivery of nutrients and oxygen to organs. However, the effect of blood administration on tissue oxygenation in the perioperative setting remains poorly understood. QUESTIONS/PURPOSES: The aim of this study was to determine changes in muscle tissue oxygenation saturation (SmO2) in response to perioperative blood transfusions. PATIENTS AND METHODS: Patients undergoing total knee arthroplasty were enrolled. SmO2, continuous hemoglobin (SpHb), stroke volume (SV), cardiac index, and standard hemodynamic parameters including heart rate (HR), mean arterial blood pressure (MAP), and arterial oxygen saturation (SO2) were recorded. To assess fluid responsiveness, a passive leg raise (PLR) test was performed before the transfusions were started. RESULTS: Twenty-eight patients were included in the analysis. Mean (+/-SD) SmO2 before transfusion was 63.18 +/- 10.04%, SpHb was 9.27 +/- 1.16 g/dl, and cardiac index was 2.62 +/- 0.75 L/min/m(2). A significant increase during the course of blood transfusion was found for SmO2 (+3.44 +/- 5.81% [95% confidence interval (CI) 1.04 to 5.84], p = 0.007), SpHb (0.74 +/- 0.92 g/dl [95% CI 0.35 to 1.12], p \u3c 0.001), and cardiac index (0.38 +/- 0.51 L/min/m2 [95% CI 0.15 to 0.60], p = 0.002), respectively. However, the correlation between SmO2 and SpHb over the course of the transfusion was negligible (rho = 0.25 [95% CI -0.03 to 0.48]). A similar lack of correlation was found when analyzing data of those patients who showed a positive leg raise test before the start of the transfusion (rho = 0.37 [95% CI -0.11 to 0.84]). CONCLUSION: We detected a statistically significant increase in SmO2 during the course of a single unit blood transfusion compared to baseline. However, there was no evidence of a correlation between longitudinal SmO2 and SpHb measurements