Non-invasive hemoglobin estimation for preoperative anemia screening.

BACKGROUND: Preoperative anemia is common and associated with adverse postoperative outcomes. Assessment of hemoglobin concentrations may facilitate optimization prior to surgery. However, phlebotomy-based hemoglobin measurement may contribute to patient discomfort and iatrogenic blood loss, which makes non-invasive hemoglobin estimation attractive in this setting. STUDY DESIGN AND METHODS: This is a prospective study of adult patients presenting for preoperative evaluation before elective surgery at a tertiary care medical center. The Masimo Pronto Pulse CO-Oximeter was utilized to estimate blood hemoglobin concentrations (SpHb), which were then compared with hemoglobin concentrations obtained via complete blood count. Receiver operating curves were used to identify SpHb values maximizing specificity for anemia detection while meeting a minimum sensitivity of 80%. RESULTS: A total of 122 patients were recruited with a median (interquartile range) age of 66 (58, 72) years. SpHb measurements were obtained in 112 patients (92%). SpHb generally overestimated hemoglobin with a mean (± 1.96 × standard deviation) difference of 0.8 (-2.2, 3.9) g/dL. Preoperative anemia, defined by hemoglobin <12.0 g/dL in accordance with institutional protocol, was present in 22 patients (20%). The optimal SpHb cut-point to identify anemia was 13.5 g/dL: sensitivity 86%, specificity 81%, negative predictive value 96%, and positive predictive value 53%. Utilizing this cut-point, 60% (73/122) of patients could have avoided phlebotomy-based hemoglobin assessment, while an anemia diagnosis would have been missed in <3% (3/122). CONCLUSION: The use of SpHb devices for anemia screening in surgical patients is feasible with the potential to reliably rule-out anemia despite limited accuracy.

Intraoperative Fluid Management a Modifiable Risk Factor for Surgical Quality - Improving Standardized Practice.

OBJECTIVE: We aimed to determine a safe zone of intraoperative fluid management associated with the lowest postoperative complication rates without increased acute kidney injury (AKi) risk for elective colorectal surgery patients. BACKGROUND: To date, standard practice within institutions, let alone national expectations related to fluid administration, are limited. This fact has perpetuated a quality gap. METHODS: Elective colorectal surgeries between 2018 and 2020 were included. Unadjusted odds ratios (ORs) for postoperative ileus, prolonged LOS, and AKi were plotted against the rate of intraoperative RL infusion (mL/ kg/h) and total intraoperative volume. Binary logistic regression analysis, including fluid volumes as a confounder, was used to identify risk factors for postoperative complications. RESULTS: A total of 2900 patients were identified. Of them, 503 (17.3%) patients had ileus, 772 (26.6%) patients had prolonged LOS, and 240 (8.3%) patients had AKI. The intraoperative fluid resuscitation rate (mg/kg/h) was less impactful on postoperative ileus, LOS, and AKI than the total amount of intraoperative fluid. A total fluid administration range between 300 mL and 2.7 L was associated with the lowest complication rate. Total intraoperative RL ≥2.7 L was independently associated with a higher risk of ileus (adjusted OR 1.465; 95% confidence interval 1.154-1.858) and prolonged LOS (adjusted OR 1.300; 95% confidence interval 1.047-1.613), but not AKI. Intraoperative RL ≤300 mL was not associated with an increased risk of AKI. CONCLUSION: Total intraoperative RL ≥2.7 L was independently associated with postoperative ileus and prolonged LOS in elective colorectal surgery patients. A new potential standard for intraoperative fluids will require anesthesia case planning (complexity and duration) to ensure total fluid volume meets this new opportunity to improve care.

Obstetric Anesthetic Management for Parturients with Hereditary Angioedema: A Case Report and Suggested Protocol.

Hereditary angioedema (HAE) is a disease manifested by repeated episodes of localized submucosal or subcutaneous edematous episodes, potentially triggered by emotional stress, mechanical trauma, or intake of estrogens. We present our experience managing two parturients with HAE. Multidisciplinary care is essential for planning and executing the specialized care of these patients, and management included extensive planning among obstetric, anesthesiology, and allergy and immunology teams. Pregnancy has been shown to have a variable effect on triggering HAE episodes. First-line treatment includes C1 esterase inhibitor concentrate, which can also be used for prophylaxis in high-risk patients. Neuraxial analgesia is recommended to avoid general anesthesia and was established early in both individuals. Vaginal delivery was well tolerated without need for emergent treatment for angioedema symptoms.

Intrathecal Morphine versus Intrathecal Hydromorphone for Analgesia after Cesarean Delivery: A Randomized Clinical Trial.

BACKGROUND: Intrathecal opioids are routinely administered during spinal anesthesia for postcesarean analgesia. The effectiveness of intrathecal morphine for postcesarean analgesia is well established, and the use of intrathecal hydromorphone is growing. No prospective studies have compared the effectiveness of equipotent doses of intrathecal morphine versus intrathecal hydromorphone as part of a multimodal analgesic regimen for postcesarean analgesia. The authors hypothesized that intrathecal morphine would result in superior analgesia compared with intrathecal hydromorphone 24 h after delivery. METHODS: In this single-center, double-blinded, randomized trial, 138 parturients undergoing scheduled cesarean delivery were randomized to receive 150 µg of intrathecal morphine or 75 µg of intrathecal hydromorphone as part of a primary spinal anesthetic and multimodal analgesic regimen; 134 parturients were included in the analysis. The primary outcome was the numerical rating scale score for pain with movement 24 h after delivery. Static and dynamic pain scores, nausea, pruritus, degree of sedation, and patient satisfaction were assessed every 6 h for 36 h postpartum. Total opioid consumption was recorded. RESULTS: There was no significant difference in pain scores with movement at 24 h (intrathecal hydromorphone median [25th, 75th] 4 [3, 5] and intrathecal morphine 3 [2, 4.5]) or at any time point (estimated difference, 0.5; 95% CI, 0 to 1; P = 0.139). Opioid received in the first 24 h did not differ between groups (median [25th, 75th] oral morphine milligram equivalents for intrathecal hydromorphone 30 [7.5, 45.06] vs. intrathecal morphine 22.5 [14.0, 37.5], P = 0.769). From Kaplan-Meier analysis, the median time to first opioid request was 5.4 h for hydromorphone and 12.1 h for morphine (log-rank test P = 0.200). CONCLUSIONS: Although the hypothesis was that intrathecal morphine would provide superior analgesia to intrathecal hydromorphone, the results did not confirm this. At the doses studied, both intrathecal morphine and intrathecal hydromorphone provide effective postcesarean analgesia when combined with a multimodal analgesia regimen.

Interspace between Popliteal Artery and posterior Capsule of the Knee (IPACK) Injectate Spread: A Cadaver Study.

OBJECTIVES: Local anesthetic injection into the interspace between the popliteal artery and the posterior capsule of the knee (IPACK) has the potential to provide motor-sparing analgesia to the posterior knee after total knee arthroplasty. The primary objective of this cadaveric study was to evaluate injectate spread to relevant anatomic structures with IPACK injection. METHODS: After receipt of Institutional Review Board Biospecimen Subcommittee approval, IPACK injection was performed on fresh-frozen cadavers. The popliteal fossa in each specimen was dissected and examined for injectate spread. RESULTS: Ten fresh-frozen cadaver knees were included in the study. Injectate was observed to spread in the popliteal fossa at a mean ± SD of 6.1 ± 0.7 cm in the medial-lateral dimension and 10.1 ± 3.2 cm in the proximal-distal dimension. No injectate was noted to be in contact with the proximal segment of the sciatic nerve, but 3 specimens showed injectate spread to the tibial nerve. In 3 specimens, the injectate showed possible contact with the common peroneal nerve. The middle genicular artery was consistently surrounded by injectate. CONCLUSIONS: This cadaver study of IPACK injection demonstrated spread throughout the popliteal fossa without proximal sciatic involvement. However, the potential for injectate to spread to the tibial or common peroneal nerve was demonstrated. Consistent surrounding of the middle genicular artery with injectate suggests a potential mechanism of analgesia for the IPACK block, due to the predictable relationship between articular sensory nerves and this artery. Further study is needed to determine the ideal site of IPACK injection.

A 3-arm randomized clinical trial comparing interscalene blockade techniques with local infiltration analgesia for total shoulder arthroplasty.

BACKGROUND: The ideal analgesic modality for total shoulder arthroplasty (TSA) remains controversial. We hypothesized that a multimodal analgesic pathway incorporating continuous interscalene blockade (ISB) provides better analgesic efficacy than both single-injection ISB and local infiltration analgesia. METHODS: This single-center, parallel, unblinded, randomized clinical trial evaluated 129 adults undergoing primary TSA. Patients were allocated to single-injection ISB, continuous ISB, or local infiltration analgesia. The primary outcome was the Overall Benefit of Analgesia Score (range, 0 [best] to 28 [worst]) on postoperative day 1. Additional outcomes included pain scores, opioid consumption, quality of life, and postoperative complications in the first 24 hours, at 3 months, and at 1 year. RESULTS: We analyzed 125 patients (42 with single-injection ISB, 41 with continuous ISB, and 42 with local infiltration analgesia). The Overall Benefit of Analgesia Score was significantly improved in the continuous group (median [25th percentile, 75th percentile], 0 [0, 2]) compared with the single-injection group (2 [1, 4]; P = .002) and local infiltration analgesia group (3 [2, 4]; P < .001). Pain scores were significantly lower in the continuous group compared with the local infiltration analgesia group (P < .001 for all time points) and after 12 hours from ward arrival compared with the single-injection group (median [25th percentile, 75th percentile], 1.0 [0.0, 2.8] vs. 2.5 [0.0, 4.0]; P = .016). After postanesthesia recovery discharge, opioid consumption (oral morphine equivalents) was significantly lower in the continuous group (median [25th percentile, 75th percentile], 7.5 mg [0.0, 25.0 mg]) than in the local infiltration analgesia group (30 mg [15.0, 52.5 mg]; P < .001) and single-injection group (17.6 mg [7.5, 45.5 mg]; P = .010). No differences were found across groups for complications, 3-month outcomes, and 1-year outcomes. CONCLUSION: Continuous ISB provides superior analgesia compared with single-injection ISB and local infiltration analgesia in the first 24 hours after TSA.

Early Diuresis After Colon and Rectal Surgery Does Not Reduce Length of Hospital Stay: Results of a Randomized Trial.

BACKGROUND: Excessive perioperative fluid administration likely increases postoperative cardiovascular, infectious, and GI complications. Early administration of diuretics after elective surgery facilitates rapid mobilization of excess fluid, potentially leading to decreased bowel edema, more rapid return of bowel function, and reduced length of hospital stay. OBJECTIVE: This study aimed to evaluate the benefit of early diuresis after elective colon and rectal surgery in the setting of an enhanced recovery after surgery practice. DESIGN: This was a prospective study. SETTINGS: The study was conducted at a quaternary referral center. PATIENTS: A randomized, open-label, parallel-group trial was conducted in patients undergoing elective colon and rectal surgery at a single quaternary referral center. INTERVENTION: The primary intervention was administration of intravenous furosemide plus enhanced recovery after surgery on postoperative day 1 and 2 versus enhanced recovery after surgery alone. MAIN OUTCOME MEASURES: The primary outcome was length of hospital stay. Secondary outcomes included 30-day readmission rate, time to stool output during hospitalization after surgery, and incidence of various complications within the first 48 hours of hospital stay. RESULTS: In total, 123 patients were randomly assigned to receive either furosemide plus enhanced recovery after surgery (n = 62) or enhanced recovery after surgery alone (n = 61). Groups were evenly matched at baseline. At interim analysis, length of hospital stay was not superior in the intervention group (80.6 vs 99.6 hours, p = 0.564). No significant difference was identified in the rates of nasogastric tube replacement (1.6% vs 9.7%, p = 0.125). Time to return of bowel function was significantly longer in the intervention group (45.4 vs 48.8 hours, p = 0.048). The decision was made to end the study early because the conditional power of the study favored futility. LIMITATIONS: This was a single-center study. CONCLUSIONS: Early administration of furosemide does not significantly reduce the length of hospital stay after elective colon and rectal surgery in the setting of enhanced recovery after surgery practice. See Video Abstract at http://links.lww.com/DCR/A714.

Intrathecal Hydromorphone and Morphine for Postcesarean Delivery Analgesia: Determination of the ED90 Using a Sequential Allocation Biased-Coin Method.

BACKGROUND: Intrathecal (IT) morphine is considered the "gold standard" for analgesia after cesarean delivery under spinal anesthesia, most commonly administered at a dose of 100 to 200 µg. There is less experience with IT hydromorphone for postcesarean analgesia and limited information on its optimal analgesic dose. We conducted this study to determine the effective analgesic dose for 90% patients (ED90) of IT hydromorphone that provides effective analgesia for women undergoing elective cesarean delivery and its potency ratio to IT morphine. METHODS: In this dose-finding trial, 80 patients received spinal anesthesia for cesarean delivery. Participants were randomized to receive IT morphine or IT hydromorphone at a dose determined using up-down sequential allocation with a biased-coin design to determine ED90. All patients received standardized multimodal analgesia postoperatively in addition to IT opioid. An effective dose was defined as a numeric response score for pain of ≤3 (scale 0-10) 12 hours after spinal injection. RESULTS: The ED90 was 75 µg (95% confidence interval [CI], 46-93 µg) for IT hydromorphone and 150 µg (95% CI, 145-185 µg) for IT morphine. At these doses, the 95% CI for the percentage of patients with effective analgesia (numeric rating scale ≤3) was 64% to 100% for hydromorphone and 68% to 100% for morphine. Exploratory findings showed that the incidence of nausea and pruritus was not different among the most commonly used doses of IT hydromorphone (P = 0.44 and P = 0.74) or IT morphine (P = 0.67 and P = 0.38, respectively). When administering IT opioids at ED90 doses or higher, 100% (21/21) of IT hydromorphone and 95% (37/39) of IT morphine patients were satisfied with their analgesia. CONCLUSIONS: The ratio of IT morphine to IT hydromorphone for effective postcesarean analgesia is 2:1. Patient satisfaction was high with both medications.

Current tobacco use is associated with higher rates of implant revision and deep infection after total hip or knee arthroplasty: a prospective cohort study.

BACKGROUND: Tobacco smoking is a risk factor for several adverse post-operative outcomes. We aimed to compare the rates of complications in current tobacco users and non-users who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA). METHODS: All patients who underwent primary THA or TKA at the Mayo Clinic from 2010-2013 were included in the study. Current tobacco use was defined as the use of cigarettes, cigars, pipes, or smokeless tobacco reported at the time of index THA or TKA; current non-users were former users or never users. We used Cox proportional hazards regression to assess the association of current tobacco use status with each post-THA/TKA complication, using hazard ratios and 95% confidence intervals (CI). RESULTS: Tobacco use status was available for 7926 patients (95%) and not available for 446 patients (5%); 565 (7%) were current tobacco users. Compared to non-users, current tobacco users were more likely to be male (p < 0.001), and less likely to be obese (p ≤ 0.008), be older than 60 years, have Charlson score >0 or have undergone TKA rather than THA (p < 0.001 each). The hazard ratios for deep infection (2.37; 95% CI 1.19, 4.72; p = 0.01) and implant revision (1.78; 95% CI 1.01, 3.13; p = 0.04) were higher in current tobacco users than in non-users. No significant differences were noted for periprosthetic fractures or superficial infections. CONCLUSIONS: We noted that current tobacco use was associated with high risk of deep infection and implant revision after primary THA or TKA. Future studies should determine the optimal time for tobacco use cessation before elective surgeries such as THA and TKA to improve short-term and long-term arthroplasty outcomes.

Does Intravenous Midazolam Dose Influence the Duration of Recovery Room Stay Following Outpatient Third Molar Surgery?

PURPOSE: To evaluate the impact of intravenous midazolam dose on the duration of recovery room stay for patients undergoing outpatient third molar surgery. MATERIALS AND METHODS: Using a retrospective cohort study design, a sample of patients undergoing outpatient third molar surgery under intravenous sedation at Mayo Clinic from 2010 to 2014 was identified. All patients underwent extraction of all 4 third molars during a single operative procedure and the age range was limited to 14 to 29 years. The primary predictor variable was the total dose of intravenous midazolam administered during sedation. The primary outcome variable was recovery room length of stay (LOS) after completion of surgery. Multiple covariates also abstracted included patient age, gender, American Society of Anesthesiologists (ASA) score, duration of surgical procedure, complexity of surgical procedure, types and dosages of all intravenous medications administered during sedation, and volume of crystalloid fluid administered perioperatively. Univariable and multivariable models were developed to evaluate associations between the primary predictor variable and covariates relative to the primary outcome variable. RESULTS: The study sample was composed of 2,610 patients. Mean age was 18.3 years (SD, 3.0 yr; range, 14 to 29 yr) and gender distribution was 52% female. Mean dosage of midazolam administered was 4.1 mg (SD, 1.1 mg; range, 0.5 to 10.0 mg). Variables predicting shorter LOS at multivariable analysis included older age (P < .001), male gender (P = .004), and administration of larger crystalloid fluid volumes (P < .001). Variables predicting longer LOS included higher ASA score (P < .001), administration of ketamine (P < .001), and administration of ketorolac (P < .001). The dose of midazolam administered during sedation was not found to be significantly associated with prolonged recovery room LOS in univariable or multivariable settings. CONCLUSION: Dosage of intravenous midazolam does not appear to significantly impact the duration of recovery room stay in the prototypical patients undergoing sedation for outpatient third molar surgery.

Venous thromboembolism and mortality associated with tranexamic acid use during total hip and knee arthroplasty.

TKA and THA are associated with blood transfusion and risk for postoperative venothromboembolism (VTE). Reports show that tranexamic acid (TA) may be safe to use in high-risk orthopedic patients, but further data are needed to substantiate its use. All patients who underwent primary or revision TKA or THA in a five year period were retrospectively identified. In 13,262 elective TKA or THA procedures, neither the odds of VTE (OR=0.98; 95% CI 0.67-1.45; P=0.939) or adjusted odds of death (OR=0.26; 95% CI 0.04-1.80; P=0.171) were significant with TA administration. The major findings of this large, single center, retrospective cohort study show the odds of postoperative VTE and 30-day mortality were unchanged with TA administration.

Continuing clopidogrel during elective total hip and knee arthroplasty: assessment of bleeding risk and adverse outcomes.

Limited research assessing risks of continued clopidogrel perioperatively in patients undergoing elective orthopedic procedures exists. Patients that underwent elective primary or revision total knee arthroplasty (TKA) or total hip arthroplasty (THA) from 2007 to 2012 while taking clopidogrel at the time of surgical evaluation were retrospectively identified. Patient demographics, last dose of clopidogrel, intraoperative blood loss, blood transfusion, and presence of 30-day adverse cardiac events (ACE) were collected. Of 142 patients meeting criteria, 24 (16.9%) patients remained on clopidogrel perioperatively. Patients that continued clopidogrel were more likely to receive a blood transfusion within 24 hours of surgery (31.8% vs. 7.7%; P=0.004) and during hospitalization (37.5% vs. 15.3%; P=0.02), but the incidence of 30-day ACE was not significantly different. Continuation of clopidogrel perioperatively for elective THA or TKA should be carefully considered.

Peer Support and Second Victim Programs for Anesthesia Professionals Involved in Stressful or Traumatic Clinical Events.

Modern anesthetic care is very safe, but stressful and traumatic clinical events may occur. When they occur, anesthesia professionals are vulnerable to second victim experiences, resulting in significant and long-lasting psychological and emotional consequences if not addressed. Peer support can help anesthesia professionals cope with the negative effects of second victim experiences.

Preoperative Evaluation and Management of Patients With Select Chronic Gastrointestinal, Liver, and Renal Diseases.

Patients with chronic gastrointestinal, hepatic, and renal disease are frequently encountered in clinical practice. This is due in part to the rising prevalence of risk factors associated with these conditions. These patients are increasingly being considered for surgical intervention and are at higher risk for multiple perioperative complications. Many are able to safely undergo surgery but require unique considerations to ensure optimal perioperative care. In this review, we highlight relevant perioperative physiology and outline our approach to the evaluation and management of patients with select chronic gastrointestinal, hepatic, and renal diseases. A comprehensive preoperative evaluation with a multidisciplinary approach is often beneficial, and specialist involvement should be considered. Intraoperative and postoperative plans should be individualized based on the unique medical and surgical characteristics of each patient.

Perioperative nerve injury after total knee arthroplasty: regional anesthesia risk during a 20-year cohort study.

BACKGROUND: Perioperative nerve injury (PNI) is one of the most debilitating complications after total knee arthroplasty (TKA). Although regional anesthesia (RA) techniques reduce pain and improve functional outcomes after TKA, they may also contribute to PNI. The objective of this study was to test the hypothesis that PNI risk differs among patients according to RA use during TKA. METHODS: All patients aged at least 18 yr who underwent elective TKA from January 1988 to July 2007 were retrospectively identified. The primary outcome variable was the presence of a new PNI documented within 3 months of the procedural date. Age, sex, body mass index, type of procedure, tourniquet time, type of anesthesia, and use of peripheral nerve blockade were evaluated as potential risk factors for PNI using multivariable logistic regression. RESULTS: Ninety-seven cases of PNI were identified among 12,329 patients. Overall incidence of PNI was 0.79% (95% CI, 0.64-0.96%). PNI was not associated with peripheral nerve blockade (odds ratio [OR], 0.97) or type of anesthesia (OR, 1.10 [neuraxial vs. general]; OR, 1.82 [combined vs. general]). Risk for PNI decreased with age (OR, 0.68 [per decade]; P < 0.001) but increased with tourniquet time (OR, 1.28 [per 30-min increase]; P = 0.003) and bilateral procedures (OR, 2.51; P < 0.001). Patients with PNI who underwent peripheral nerve blockade were less likely to have complete neurologic recovery (OR, 0.37; P = 0.03). CONCLUSIONS: Risk for PNI after TKA was unchanged by the use of RA techniques. This finding supports the notion that the known benefits of RA for patients undergoing TKA can be achieved without increasing risk of neurologic injury. However, in rare situations when PNI occurs, complete recovery may be less likely if it develops after peripheral nerve blockade.

Perioperative nerve injury after total hip arthroplasty: regional anesthesia risk during a 20-year cohort study.

BACKGROUND: Perioperative nerve injury (PNI) is a recognized complication of total hip arthroplasty (THA). Regional anesthesia (RA) techniques may increase the risk of neurologic injury. Using a retrospective cohort study, the authors tested the hypothesis that use of RA increases the risk for PNI after elective THA. METHODS: All adult patients who underwent elective THA at Mayo Clinic during a 20-yr period were included. The primary outcome was the presence of a new PNI within 3 months of surgery. Multivariable logistic regression was used to evaluate patient, surgical, and anesthetic risk factors for PNI. RESULTS: Of 12,998 patients undergoing THA, 93 experienced PNI (incidence = 0.72%; 95% CI 0.58-0.88%). PNI was not associated with type of anesthesia (OR = 0.72 for neuraxial-combined vs. general; 95% CI 0.46-1.14) or peripheral nerve blockade (OR = 0.65; 95% CI 0.34-1.21). The risk for PNI was associated with younger age (OR = 0.79 per 10-yr increase; 95% CI 0.69-0.90), female gender (OR = 1.72; 95% CI 1.12-2.64), longer operations (OR = 1.10 per 30-min increase; 95% CI 1.03-1.18) or posterior surgical approach (OR = 1.91 vs. anterior approach; 95% CI 1.22-2.99). Neurologic recovery was not influenced by the use of RA techniques in patients with PNI. CONCLUSIONS: The risk for PNI after THA was not increased with the use of neuraxial anesthesia or peripheral nerve blockade. Neurologic recovery in patients who experienced PNI was not affected by the use of RA. These results support the use of RA techniques in patients undergoing elective THA given their known functional and clinical benefits.