Empirical guide to a safe thoracic paravertebral block based on dimensions of paravertebral space when ultrasound visualization is challenging

Although ultrasound (US) guidance is the mainstay technique for performing thoracic paravertebral blocks, situations arise when US imaging is limited due to subcutaneous emphysema or extremely deep structures. A detailed understanding of the anatomical structures of the paravertebral space can be strategic to safely and accurately perform a landmark-based or US-assisted approach. As such, we aimed to provide an anatomic roadmap to assist physicians. We examined 50 chest CT scans, measuring the distances of the bony structures and soft-tissue surrounding the thoracic paravertebral block at the 2nd/3rd (upper), 5th/6th (middle), and 9th/10th (lower) thoracic vertebral levels. This review of radiology records controlled for individual differences in body mass index, gender, and thoracic level. Midline to the lateral aspect of the transverse process (TP), the anterior-to-posterior distance of TP to pleura, and rib thickness range widely based on gender and thoracic level. The mean thickness of the TP is 0.9±0.1 cm in women and 1.1±0.2 cm in men. The best target for initial needle insertion from the midline (mean length of TP minus 2 SDs) distance would be 2.5 cm (upper thoracic)/2.2 cm (middle thoracic)/1.8 cm (lower thoracic) for females and 2.7 cm (upper)/2.5 cm (middle)/2.0 cm (lower thoracic) for males, with consideration that the lower thoracic region allows for a lower margin of error in the lateral dimension because of shorter TP. There are different dimensions for the key bony landmarks of a thoracic paravertebral block between males and females, which have not been previously described. These differences warrant adjustment of landmark-based or US-assisted approach to thoracic paravertebral space block for male and female patients.

Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of upper and lower limb nerve blocks

BACKGROUND

Inconsistent nomenclature and anatomical descriptions of regional anesthetic techniques hinder scientific communication and engender confusion; this in turn has implications for research, education and clinical implementation of regional anesthesia. Having produced standardized nomenclature for abdominal wall, paraspinal and chest wall regional anesthetic techniques, we aimed to similarly do so for upper and lower limb peripheral nerve blocks.

METHODS

We performed a three-round Delphi international consensus study to generate standardized names and anatomical descriptions of upper and lower limb regional anesthetic techniques. A long list of names and anatomical description of blocks of upper and lower extremities was produced by the members of the steering committee. Subsequently, two rounds of anonymized voting and commenting were followed by a third virtual round table to secure consensus for items that remained outstanding after the first and second rounds. As with previous methodology, strong consensus was defined as ≥75% agreement and weak consensus as 50%-74% agreement.

RESULTS

A total of 94, 91 and 65 collaborators participated in the first, second and third rounds, respectively. We achieved strong consensus for 38 names and 33 anatomical descriptions, and weak consensus for five anatomical descriptions. We agreed on a template for naming peripheral nerve blocks based on the name of the nerve and the anatomical location of the blockade and identified several areas for future research.

CONCLUSIONS

We achieved consensus on nomenclature and anatomical descriptions of regional anesthetic techniques for upper and lower limb nerve blocks, and recommend using this framework in clinical and academic practice. This should improve research, teaching and learning of regional anesthesia to eventually improve patient care.

Incidence of acute compartment syndrome with routine use of regional anesthesia for patients with long bone fractures: a large single-center retrospective review from a level I trauma tertiary academic institution

INTRODUCTION

Traditionally, using peripheral nerve blocks (PNBs) in patients with long bone fractures has been limited due to concerns that it may interfere with the timely diagnosis of acute compartment syndrome (ACS). However, our large academic institution and level I trauma center have been using regional anesthesia routinely for pain management of patients with long bone fractures for more than a decade, with strict adherence to a comprehensive management protocol. The aim of this retrospective review is to present our experience with this practice.

METHODS

Following Institutional Review Board approval, we performed a retrospective chart review of patients with long bone fractures and ACS over a 10-year period (2008-2018).

RESULTS

26 537 patients were included in the review. Approximately 20% of these patients required surgery, and 91.5% of surgically treated patients received regional anesthesia. The incidence of ACS in our cohort was 0.1% or 1.017 per 1000 patients with long bone fractures.

CONCLUSION

Current recommendations on using PNBs in patients at risk for ACS have been mainly based on expert opinion and dated case reports. Due to the nature of the condition, prospective data are lacking. Our large observational dataset evaluated the risk of missing or delaying ACS diagnosis when PNBs were offered for trauma patients and demonstrated a relatively low incidence of ACS despite the routine use of PNBs under strictly protocolized conditions when patients were managed by a dedicated multidisciplinary care team.

Comparing Spinal Chloroprocaine to Hyperbaric and Isobaric Bupivacaine for Total Hip and Knee Arthroplasties: A Retrospective Study

INTRODUCTION

Spinal anesthesia is commonly used for total knee and hip arthroplasties (TKA/THA). The rising popularity of ambulatory TKA and THAs require anesthetic techniques that provide rapid recovery of motor and sensory function while minimizing side effects like postoperative urinary retention. This single-center retrospective observational study compares the recovery profile of patients undergoing TKA and THA under chloroprocaine spinals compared to hyperbaric and isobaric bupivacaine spinals.

METHODS

One hundred and twelve patients undergoing primary TKA and THA under spinal anesthesia at University of Florida Health were identified between September 1, 2019 and February 21, 2020. Their electronic medical records were reviewed. Patients were categorized based on the local anesthetic used in the spinal. Various demographic, intraoperative, and postoperative data were compiled and compared, including duration of surgery, time to physical therapy, time to post-anesthesia care unit (PACU) discharge, and time to spontaneous micturition.

RESULTS

Time to spontaneous micturition and PACU discharge were significantly lower in the chloroprocaine spinal group compared to the hyperbaric bupivacaine group by 193 minutes and 42 minutes, respectively. Fewer patients receiving chloroprocaine spinals had their first physical therapy session limited by residual motor weakness compared to those in both bupivacaine groups. Additionally, mean duration of surgery was shorter in the chloroprocaine group compared to both bupivacaine groups (89 minutes compared to 111 minutes). Time to physical therapy completion was not different. All groups had <10% conversion to general anesthesia.

CONCLUSION

Chloroprocaine spinals can be feasible options for TKAs and THAs with improved postoperative recovery profiles compared to bupivacaine spinals.

Gastric Emptying of Orange Juice With and Without Pulp: A Point-of-Care Ultrasound Study

Purpose The American Society of Anesthesiologists (ASA) preoperative fasting recommendations regarding fruit juice with pulp is unclear. In addition, it is debatable whether orange juice without pulp should be treated as a clear liquid. Our objective is to determine the gastric emptying time of orange juice with and without pulp. Methods This is an observational study of gastric emptying time using point-of-care ultrasound (POCUS). Thirty-five adult volunteers were enrolled in this study. Exclusion criteria included pregnancy, diabetes, body mass index > 40 kg/m², previous lower esophageal or upper abdominal surgery, hiatal hernia, and upper gastrointestinal bleed. The study was carried out on three separate days for each volunteer. After fasting a minimum of 8 h, the volunteers were asked to drink 240 ml of water on day 1, orange juice without pulp on day 2, and orange juice with pulp on day 3. Gastric volumes were estimated using gastric antrum cross-sectional area at fasting state, and then 30, 60, 90 120, 180, and 240 min after drinking until the gastric volume returned to baseline. Results A gastric volume of 1.5 mL/kg was defined as a baseline. All subjects' gastric volume returned to baseline 90 min after drinking water. More than 97% of the subjects who drank orange juice without pulp and 93.9% of the subjects who drank orange juice with pulp reached a gastric volume of less than 1.5 mL/kg after 2 h. All subjects' gastric volume returned to baseline 3 h after drinking orange juice with pulp. Conclusions Orange juice without pulp can be treated as a clear liquid in a majority of patients who do not have conditions that would cause delayed gastric emptying. Orange juice with pulp required 3 h to empty.

Development of entrustable professional activities for regional anesthesia and pain medicine fellowship training

INTRODUCTION

The Accreditation Council for Graduate Medical Education (ACGME) offers descriptions of competencies and milestones but does not provide standardized assessments to track trainee competency. Entrustable professional activities (EPAs) and special assessments (SAs) are emerging methods to assess the level of competency obtained by regional anesthesiology and acute pain medicine (RAAPM) fellows.

METHODS

A panel of RAAPM physicians with experience in education and competency assessment and one medical student were recruited to participate in a modified Delphi method with iterative rounds to reach consensus on: a list of EPAs, SAs, and procedural skills; detailed definitions for each EPA and SA; a mapping of the EPAs and SAs to the ACGME milestones; and a target level of entrustment for graduating US RAAPM fellows for each EPA and procedural skill. A gap analysis was performed and a heat map was created to cross-check the EPAs and SAs to the ACGME milestones.

RESULTS

Participants in EPA and SA development included 19 physicians and 1 medical student from 18 different programs. The Delphi rounds yielded a final list of 23 EPAs, a defined entrustment scale, mapping of the EPAs to ACGME milestones, and graduation targets. A list of 73 procedural skills and 7 SAs were similarly developed.

DISCUSSION

A list of 23 RAAPM EPAs, 73 procedural skills, and 7 SAs were created using a rigorous methodology to reach consensus. This framework can be utilized to help assess RAAPM fellows in the USA for competency and allow for meaningful performance feedback.

Role of an Intercostobrachial Nerve Block in Alleviating Tourniquet Pain: A Randomized Clinical Trial

Introduction

Tourniquet pain may have cutaneous and ischemic components. It is questionable whether blockade of a sensory nerve will help reduce ischemic pain. In addition, complete anesthesia of the axilla in the intercostobrachial nerve (ICBN) distribution is challenging to execute, and ICBN blockade has an inherently higher failure rate because of its variable anatomic location and source of innervation. We sought to determine the utility of an ICBN block for the prevention of tourniquet pain.

Methods

We conducted a single-center randomized controlled trial at a major academic medical center involving patients scheduled to undergo distal upper extremity surgery under ultrasound-guided supraclavicular brachial plexus block. Forty patients were randomized to receive an additional ICBN block or no ICBN block, with 22 allocated to the intervention and 18 to control. We collected data on the incidence of tourniquet pain and systemic anesthetic requirements.

Results

Initial contingency analysis examining the relationship between ICBN block placement and the development of pain using the two-tailed Fisher exact test failed to show that the presence or absence of ICBN block was associated with the development of tourniquet pain. χ² analysis failed to show that tourniquet time was significantly related to the development of tourniquet pain.

Conclusions

The overall incidence of tourniquet pain in the setting of a dense supraclavicular brachial plexus block for surgical anesthesia was low even without an ICBN block and even with tourniquet times greater than 90 min. Tourniquet pain was easily managed with small amounts of systemic analgesics.

Efficacy of Phrenic Nerve Catheter in Ipsilateral Shoulder Pain After Thoracic Surgery

The mechanism of ipsilateral shoulder pain (ISP) after thoracic surgery remains unexplained definitively in the literature. Regional techniques targeting specific nerves more precisely will provide practitioners with a better understanding of the pain source. We report the case of a 51-year-old woman who underwent robotic-assisted plication of the right hemidiaphragm. ISP was adequately managed using a low-volume infusion through a continuous phrenic nerve block in addition to a thoracic epidural for her chest pain. ISP after thoracic surgery likely originates from diaphragm manipulation. Phrenic nerve blockade is a successful strategy that does not worsen subjective dyspnea in this setting.

Cancer Recurrence and Regional Anesthesia: The Theories, the Data, and the Future in Outcomes

OBJECTIVE

More than one million people each year in the United States are diagnosed with cancer. Surgery is considered curative, but the perioperative phase represents a vulnerable period for residual disease to spread. Regional anesthesia has been proposed to reduce the incidence of recurrence by attenuating the sympathetic nervous system's response during surgery, reducing opioid requirements thus diminishing their immunosuppressant effects, and providing antitumor and anti-inflammatory effects directly through systemic local anesthetic action. In this article, we present a description of the perioperative period, a summary of the proposed hypotheses and available literature on the effects of regional anesthesia on cancer recurrence, and put regional anesthesia in context in regard to its potential role in reducing cancer recurrence during the perioperative period.

METHODS

A literature review was conducted through PubMed by examining the following topics: effects of surgery on tumor progression, roles of multiple perioperative variables (analgesics, hypothermia, blood transfusion, beta-blockade) in cancer recurrence, and available in vitro, animal, and human studies regarding the effects of regional anesthesia on cancer recurrence.

RESULTS

in vitro, animal and human retrospective studies suppport the hypothesis that in certain types of cancer, regional anesthesia may be associated with lower recurrence rates. A few well-planned human randomized clinical trials are currently under way that may provide more solid evidence to substantiate or refute the benefits of regional anesthesia in reducing cancer recurrence.

CONCLUSIONS

The benefits of regional anesthesia in reducing cancer recurrence have a sound theoretical basis and, in certain cancers, are supported by the existing body of literature. This article outlines the current state of our knowledge on the relationship between cancer progression and regional analgesia.

Regional anesthesia as compared with general anesthesia for surgery in geriatric patients with hip fracture: does it decrease morbidity, mortality, and health care costs? Results of a single-centered study

INTRODUCTION

Hip fracture in geriatric patients has a substantial economic impact and represents a major cause of morbidity and mortality in this population. At our institution, a regional anesthesia program was instituted for patients undergoing surgery for hip fracture. This retrospective cohort review examines the effects of regional anesthesia (from mainly after July 2007) vs general anesthesia (mainly prior to July 2007) on morbidity, mortality and hospitalization costs.

METHODS

This retrospective cohort study involved data collection from electronic and paper charts of 308 patients who underwent surgery for hip fracture from September 2006 to December 2008. Data on postoperative morbidity, in-patient mortality, and cost of hospitalization (as estimated from data on hospital charges) were collected and analyzed. Seventy-three patients received regional anesthesia and 235 patients received general anesthesia. During July 2007, approximately halfway through the study period, a regional anesthesia and analgesia program was introduced.

RESULTS

The average cost of hospitalization in patients who received surgery for hip fracture was no different between patients who receive regional or general anesthesia ($16,789 + 631 vs $16,815 + 643, respectively, P = 0.9557). Delay in surgery and intensive care unit (ICU) admission resulted in significantly higher hospitalization costs. Age, male gender, African American race and ICU admission were associated with increased in-hospital mortality. In-hospital mortality and rates of readmission are not statistically different between the two anesthesia groups.

CONCLUSIONS

There is no difference in postoperative morbidity, rates of rehospitalization, in-patient mortality or hospitalization costs in geriatric patients undergoing regional or general anesthesia for repair of hip fracture. Delay in surgery beyond 3 days and ICU admission both increase cost of hospitalization.