Warner, Nafisseh S.

OBJECTIVES: To assess disparities in hypoxemia detection by pulse oximetry across self-identified racial groups and associations with clinical outcomes. DESIGN: Observational cohort study from May 5, 2018, to December 31, 2020. SETTING: Three academic medical centers in the United States. PATIENTS: Adults greater than or equal to 18 years who self-identified as White, Black, Asian, or American Indian admitted to the ICU or undergoing surgery during inpatient hospitalization with simultaneous measurements of pulse oximetry-estimated oxygen saturation and arterial blood gas-derived oxygen saturation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Multivariable models were employed to assess the relationships between race, occult hypoxemia (i.e., arterial blood gas-derived oxygen saturation < 88% despite pulse oximetry-estimated oxygen saturation ≥ 92%), and clinical outcomes of hospital mortality and hospital-free days. One-hundred twenty-eight–thousand two-hundred eighty-five paired pulse oximetry-estimated oxygen saturation–arterial blood gas-derived oxygen saturation measurements were included from 26,603 patients. Pulse oximetry-estimated oxygen saturation on average overestimated arterial blood gas-derived oxygen saturation by 1.57% (1.54–1.61%). Black, Asian, and American Indian patients were more likely to experience occult hypoxemia during hospitalization (estimated probability 6.2% [5.1–7.6%], 6.6% [4.9–8.8%], and 6.6% [4.4–10.0%], respectively) compared with White patients (3.6% [3.4–3.8%]). Black patients had increased odds of occult hypoxemia compared with White patients after adjustment (odds ratio, 1.65; 1.28–2.14; p < 0.001). Differences in occult hypoxemia between Asian and American Indian patients compared with White patients were not significant after adjustment (odds ratio, 1.53; 0.95–2.47; p = 0.077 and odds ratio, 1.31; 0.80–2.16; p = 0.288, respectively). Occult hypoxemia was associated with increased odds of mortality in surgical (odds ratio, 2.96; 1.20–7.28; p = 0.019) and ICU patients (1.36; 1.03–1.80; p = 0.033). Occult hypoxemia was associated with fewer hospital-free days in surgical (–2.5 d [–3.9 to –1.2 d]; p < 0.001) but not ICU patients (0.4 d [–0.7 to 1.4 d]; p = 0.500). CONCLUSIONS: Occult hypoxemia is more common in Black patients compared with White patients and is associated with increased mortality, suggesting potentially important outcome implications for undetected hypoxemia. It is imperative to validate pulse oximetry with expanded racial inclusion.

Abstract Purpose Peripheral nerve stimulation (PNS) is a rapidly expanding field within neuromodulation; however, there is limited data on therapeutic efficacy. This study describes the indications and clinical outcomes for patients undergoing PNS for chronic pain states. Patients and Methods This is a retrospective case series of adults undergoing PNS implantation from 2004 to 2017 at an academic medical center. The primary outcomes were changes in numeric rating scale (NRS) pain scores, opioid utilization in oral morphine milligram equivalent (MME), and self‐reported patient functioning at 6 months postoperatively. Infectious and device‐related complications were also assessed. Results A total of 72 patients underwent PNS implantation, including 59 patients that received a preceding PNS trial (59/78; 76% progression rate) and 13 that did not receive a PNS trial. The most common indication for stimulation was occipital neuralgia (47%) followed by lower‐extremity neuropathies (17%). PNS implantation was associated with 6‐month reductions in pain scores (7 [6, 8] baseline vs. 4 [2, 5] 6 months; P < 0.001) and opioid utilization (eg, median 60 [31, 104] vs. 18 [0, 52] MME among those with baseline opioid use; P < 0.001). Median functional improvement was 73% (50%, 88%). Seven patients (10%) suffered a postoperative surgical site infection at a median of 50 (30, 124) days, of which five devices were removed. Conclusion Peripheral nerve stimulation was associated with reduced pain scores, lower opioid utilization, and improved patient function at 6 months. These data support PNS as a potentially effective nonopioid analgesic modality in chronic pain, though prospective multicenter evaluation is warranted to evaluate longer‐term outcomes.

AbstractBackground and ObjectivesOptimizing perioperative analgesia for patients undergoing major lower‐extremity amputation remains a considerable challenge. The utility of liposomal bupivacaine as a component of peripheral nerve blockade for lower‐extremity amputation is unknown.MethodsWe conducted an observational study comparing three different perioperative analgesic techniques for adults undergoing major lower‐extremity amputation under general anesthesia between 2012 and 2017 at an academic medical center: (1) no regional anesthesia, (2) peripheral nerve blockade with standard bupivacaine, and (3) peripheral nerve blockade with a mixture of standard and liposomal bupivacaine. The primary outcome of cumulative opioid oral morphine milligram equivalent utilization in the first 72 hours postoperatively was compared across groups utilizing multivariable linear regression.ResultsA total of 631 unique anesthetics were included for 578 unique patients, including 416 (66%) without regional anesthesia, 131 (21%) with peripheral nerve blockade with a mixture of standard and liposomal bupivacaine, and 84 (13%) with peripheral nerve blockade with standard bupivacaine alone. Cumulative morphine equivalents were lower in those receiving peripheral nerve blockade with combined standard and liposomal bupivacaine compared with those not receiving regional anesthesia (multiplicative increase 0.67; 95% CI 0.50 to 0.90; P = 0.007). There were no significant differences in opioid utilization between peripheral nerve blockade groups (P = 0.59).ConclusionsPeripheral nerve blockade is associated with reduced opioid requirements after lower‐extremity amputation compared with general anesthesia alone. However, the incorporation of liposomal bupivacaine is not significantly different to blockade employing only standard bupivacaine.

Background Women are entering medical school in record numbers, but multiple male-dominated medical specialties still exist, including pain medicine. It is not well-understood how gender diversity in academic pain medicine faculty affects fellow matriculation between female and male applicants. Objective We conducted a survey to ascertain whether gender diversity of those in leadership roles in pain medicine programs impacts the gender diversity of fellows in those programs. Methods A questionnaire was delivered to all Accreditation Council for Graduate Medical Education-accredited pain medicine fellowships to assess their demographic data in 2018. Program characteristics are summarized using median (25th, 75th) for continuous variables and frequency counts and percentages for categorical variables. Analyses were then performed using a generalized linear mixed model with a logit link function and fellowship program included as a random effect. The gender of the fellow was the dependent variable and the program characteristics were the explanatory variables. Results Data from 45 of 104 fellowship programs (43% response rate) are included. From univariate analysis, the odds of a fellow being female were higher in programs with a female program director (OR=2.17, 95% CI 1.29 to 3.65, p=0.004) and in programs with a higher percentage of female faculty (OR=1.02, 95% CI 1.00 to 1.04, p=0.027). From multivariable analysis, having a female program director was the only program characteristic found to be significantly associated with female fellows (OR=2.07, 95% CI 1.05 to 4.11, p=0.037). Conclusions Pain medicine fellowship programs with a female program director were significantly more likely to have female fellows.

Celiac plexus neurolysis has been shown to be an effective analgesic option for patients with visceral pain related to intraabdominal malignancies. In the setting of significant tumor burden, the celiac plexus may be inaccessible, limiting the efficacy of the transcrural approach. This case report describes a novel single-needle approach to retrocrural celiac plexus blockade, allowing for rapid blockade with a needle trajectory contralateral to the aorta in a 73-year-old woman with altered anatomy secondary to advanced metastatic colorectal cancer.

BACKGROUND: Noncardiac surgery (NCS) following percutaneous coronary intervention (PCI) with stenting is sometimes associated with major adverse cardiac events (MACEs). Second-generation drug-eluting stents (DES) were developed to decrease the incidence of MACE seen with bare metal and first-generation DES. METHODS: The medical records of all adult patients who underwent second-generation DES placement between July 29, 2008 and July 28, 2011 followed by NCS between September 22, 2008 and July 1, 2013 were reviewed. All episodes of MACE following surgery were recorded. RESULTS: A total of 282 patients (74.8% male) were identified who underwent NCS after PCI with second-generation DES. MACE occurred in 15 patients (5.3%), including 11 deaths. The incidence of MACE changed significantly with time from PCI to NCS: 17.1%, 10.0%, 0.0%, and 3.1% for patients undergoing NCS at 0–90, 91–180, 181–365, and ≥366 days, respectively. Compared with those having NCS ≥366 days after PCI, the odds ratio for MACE (95% confidence interval) was 6.4 (1.9 to 21.3) at 0–90 days and 3.4 (0.8 to 15.3) at 91–180 days. Seven days prior to NCS, 146 (52%) patients were on dual antiplatelet therapy (DAPT), 106 (38%) were on aspirin, and 30 (11%) did not receive antiplatelet therapy. Excessive surgical bleeding occurred in 19 cases (6.7%). While observed bleeding rates were lowest in those not receiving antiplatelet therapy, there were no statistically significant differences based on the presence or absence of antiplatelet therapy (3% [1/30] for no antiplatelet therapy compared to 6% [6/106] for aspirin monotherapy and 8% [12/146] for DAPT; Fisher exact test: P = .655). CONCLUSIONS: The incidence of MACE in patients with second-generation DES undergoing NCS was 5.3% and was highest in the first 180 days following DES implantation. The rate of excessive surgical bleeding was 6.7% with the highest observed rate in those on DAPT. However, differences by the presence or absence of antiplatelet therapy were not significant, and future large observational studies will be necessary to further define bleeding risk with continued DAPT.