Preoperative Quadratus Lumborum Block Reduces Opioid Requirements in the Immediate Postoperative Period Following Hip Arthroscopy: A Randomized, Blinded Clinical Trial

PURPOSE

To examine acute postoperative opioid consumption in patients undergoing hip arthroscopy and randomized to either receive a preoperative lateral quadratus lumborum block or sham injection.

METHODS

This trial randomized 46 subjects undergoing hip arthroscopy with a single surgeon to receive a preoperative lateral quadratus lumborum block (40 mL, ropivacaine 0.25%) or sham injection. The primary outcome was postoperative opioid consumption in patients with and without a block. All opioid medications were converted to morphine milligram equivalents for comparisons. Categorical data were compared with χ² tests and Fisher exact tests where appropriate. Continuous data were compared with 2-sided t-test and Wilcoxon rank-sum tests.

RESULTS

Forty-six subjects scheduled for elective hip arthroscopy were successfully consented and randomized. Demographic and clinical characteristics did not differ. Postoperative opioid consumption decreased 28.3% in patients who received a preoperative lateral quadratus lumborum block (P = .04). Total perioperative opioid consumption (intraoperative and postoperative combined) was reduced 20% in the block group; however, this did not achieve statistical significance (P = .05). Three subjects in the sham group (12.5%) required unblinding for a rescue block in the postoperative anesthetic care unit (PACU) for uncontrolled pain despite systemic analgesics. While cold sensation was decreased postoperatively over the abdomen (P < .001) and anterior thigh (P = .03) in the block group, other PACU variables did not differ, including VAS pain scores, motor function, side effects, PACU duration, and patient satisfaction.

CONCLUSIONS

Opioid consumption was reduced in patients who received a preoperative lateral quadratus lumborum block combined with a standardized, multimodal protocol as compared with patients who did not receive a block. Our findings support the growing evidence that quadratus lumborum blocks are an effective component of multimodal analgesia options for patients undergoing elective hip arthroscopy.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Hot-melt extrudability of amorphous solid dispersions of flubendazole-copovidone: An exploratory study of the effect of drug loading and the balance of adjuvants on extrudability and dissolution

The FDA-approved anthelmintic flubendazole has shown potential to be repositioned to treat cancer and dry macular degeneration; however, its poor water solubility limits its use. Amorphous solid dispersions may overcome this challenge, but the balance of excipients may impact the preparation method and drug release. The purpose of this study was to evaluate the influence of adjuvants and drug loading on the development of an amorphous solid dispersion of flubendazole-copovidone by hot-melt extrusion. The drug, copovidone, and adjuvants (magnesium stearate and hydroxypropyl cellulose) mixtures were statistically designed, and the process was performed in a twin-screw extruder. The study showed that flubendazole and copovidone mixtures were highly extrudable, except when drug loading was high (>40%). Furthermore, magnesium stearate positively impacted the extrusion and was more effective than hydroxypropyl cellulose. The extruded materials were evaluated by modulated differential scanning calorimetry and X-ray powder diffraction, obtaining positive amorphization and physical stability results. Pair distribution function analysis indicated the presence of drug-rich domains with medium-range order structure and no evidence of polymer-drug interaction. All extrudates presented faster dissolution (HCl, pH 1.2) than pure flubendazole, and both adjuvants had a notable influence on the dissolution rate. In conclusion, hot-melt extrusion may be a viable option to obtain stable flubendazole:copovidone amorphous dispersions.

Anesthetic Management of Severe Pulmonary Hypertension in Pregnancy

Pregnancy entails significant changes in maternal physiology that are not well-tolerated in patients with pulmonary arterial hypertension. The profound changes in plasma volume, cardiac output, and systemic vascular resistance can lead to increased strain placed on the right ventricle, leading to right-heart failure and cardiovascular collapse. Given the complex and sometimes opposing physiologic changes, managing these patients can be challenging. As such, these patients have a significantly increased reported maternal mortality rate. This report describes a parturient with newly diagnosed severe pulmonary arterial hypertension and her anesthetic management.

Impact of Tb3+ ion concentration on the morphology, structure and photoluminescence of Gd2 O2 SO4 :Tb3+ phosphor obtained using thermal decomposition of sulfate hydrate

Gadolinium oxysulfate doped with terbium (Gd₂ O₂ SO₄ :Tb³⁺ ; 0.1, 1.0, and 10.0 mol%) materials were obtained using thermal decomposition from sulfate hydrate under a dynamic air atmosphere and between 1320-1400 K. The materials were characterized using Fourier transform infrared spectroscopy, thermogravimetric/derivative thermogravimetric investigations and X-ray powder diffraction patterns. The Tb₂ O₂ SO₄ compound was obtained at 1300 K and was used to compare thermal stability and photoluminescence behaviour with that of Gd₂ O₂ SO₄ :Tb³⁺ (0.1, 1.0, and 10.0 mol%). Magnetic susceptibility measurements indicated the presence of 15% Tb⁴⁺ phases within Tb₂ O₂ SO₄ . The materials were excited at 377 nm and displayed green narrow lines with the strongest emission peak at 545.5 nm due to the ⁵ D₄ →⁷ F₅ transition of Tb³⁺ ions. Brightness of terbium-activated gadolinium oxysulfate phosphors was enhanced with increase in the concentration of Tb³⁺ . Detailed analysis of spectroscopic properties of materials under investigations revealed efficient Gd₂ O₂ SO₄ to Tb³⁺ and Tb³⁺ to Tb³⁺ energy transfers. Increase in dopant concentration led to the enhancement of ⁵ D₄ →⁷ F_J emission intensity and reduction of ⁵ D₃ →⁷ F_J emission intensity via cross-relaxation mechanisms. Distribution of particle size was increased by controlling dopant concentration in the host lattice. Obtained results confirmed that these materials could be applied potentially in field emission display devices and light-emitting diodes.

A Challenging Cesarean Delivery and Perioperative Course in a Former Polysubstance Abuser Without the Use of Traditional Opioids

Substance abuse is a major challenge in the United States. According to the Human Resources and Services Administration, we are in an opioid crisis with over 130 people a day dying from opioid-related drug overdoses. As awareness of this epidemic has grown, there has been an increase in patients coming in for surgery requesting a narcotic-free anesthetic. This presents both a challenge and an opportunity for the anesthesiologist who has a duty to respect the patient’s autonomy while simultaneously achieving the appropriate perioperative outcome. The considerations are especially important in the vulnerable population of pregnant women.

It Is Not Always the Epidural: A Case Report of Anterior Spinal Artery Ischemia in a Trauma Patient

Motor vehicle collisions impact millions of people annually resulting in multiinjury trauma. Anesthesiologists are consulted for rib fracture analgesia to improve respiratory mechanics and prevent intubation. This report describes a trauma patient who developed hypotension and lower extremity weakness after epidural placement for multiple rib fractures. Initially, hypotension was attributed to neuraxial sympathectomy. However, physical examination also indicated anterior spinal artery ischemia. Regional anesthesia and acute pain teams must be able to both identify contraindications and complications of regional techniques and discern when complications are not a result of regional interventions to initiate prompt management and definitive care.

Examination of intra-operative core temperature in joint arthroplasty: a single-institution prospective observational study

PURPOSE

Peri-operative hypothermia is associated with increased blood loss, delayed wound healing, and surgical site infections. However, it is not known when or how rapidly hypothermia develops during arthroplasty. This study observed patients undergoing lower extremity arthroplasty to identify the times of greatest heat loss or gain.

METHODS

This single-institution prospective observational study enrolled 120 patients undergoing elective knee or hip arthroplasty for peri-operative temporal temperature measurements at ten prespecified intervals. Incidence of hypothermia was the primary outcome. A secondary aim was to identify patient and operative factors associated with hypothermia. Descriptive statistics were calculated for fixed time variables. Associations for the occurrence of hypothermia over time were conducted using generalized linear mixed models with a logit link and a random subject effect to account for repeated measures on the same individual over time.

RESULTS

Most patients, 72.6%, experienced hypothermia with 20.6% hypothermic for over one hour and 47.1% hypothermic after surgery. In the multivariable model, increased odds of hypothermia were associated with female gender (P = 0.017), knee arthroplasty (P < 0.001), neuraxial anaesthesia (P < 0.001), lower patient pre-operative temperature (P < 0.001), and lower operating room temperature (P = 0.042). A 0.5 °C decrease in patient pre-operative temperature or operating room temperature was associated with a 97 and 11% increase in the odds of hypothermia, respectively, controlling for other factors.

CONCLUSION

In our series, peri-operative hypothermia remains common for patients undergoing arthroplasty. Female gender, low pre-operative temperature, knee arthroplasty, and neuraxial anesthesia were associated with hypothermia. Further preventative strategies and studies on interventions to reduce hypothermia are needed.

Hip Hemiarthroplasty in Two Patients with Severe Aortic Stenosis: Ethical Questions from an Anesthesiologist's Perspective

As the population ages, geriatric patients with preexisting cardiac disease are presenting for noncardiac surgery in escalating numbers. The decision to proceed with surgery in such patients often is multifactorial. With this in mind, we describe 2 patients with severe aortic stenosis who required hip operations: one urgent and one elective. Both patients had different anesthetic plans and did well intraoperatively. However, both patients died postoperatively because of their comorbidities. Although published guidelines are sparse, we hope this report will increase awareness and discussion about caring for geriatric patients with severe aortic stenosis.

Simultaneous pollinator occurence (Hymenoptera, Agaoninae) in a threatened species: Ficus mexiae Standley (Moraceae)

In Brazil, Ficus mexiae is classified as Vulnerable under IUCN criteria, and to date there is only one report on pollinator activity for this species. Is not unusual to find cases where more than one species of wasp simultaneously occurs on and pollinates the same fig. In this study we present evidence that two Pegoscapus wasp species contribute to the pollination of F. mexiae and relationship between pollinators maybe competitive. These results indicate that the F. mexiae population represent an important element in the complex dynamics of maintaining diversity in neotropical Ficus spp.

S-adenosylmethionine: studies on chemical and enzymatic synthesis

Several methods for the chemical and enzymatic synthesis of (-)-S-adenosylmethionine (AdoMet) are described and compared. Studies on the effects of solvents, pH, methylating reagents, and KI on the coupling of sodium homocysteine thiolate and 5'-chloro-5'-deoxyadenosine led to an improved procedure for the synthesis of (+/-)-AdoMet. The use of trimethylsulfonium iodide as a methylating agent under acidic conditions results in a higher content of the desired (-)-epimer than does the use of CH3I. The enzymatic synthesis of (-)-AdoMet using AdoMet synthetase from an over-producing strain of Escherichia coli is demonstrated and the effect of product inhibition on preparative-scale synthesis is illustrated. A new HPLC technique for separation of the epimeric mixture of AdoMet, which allows small-scale preparation of optically pure AdoMet from the enzyme product, has been developed. With this HPLC technique, evidence that (-)-AdoMet is the sole epimer formed by the enzyme has been shown.