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Background: Obesity is a risk factor for surgical site infection after cesarean delivery. There is inadequate pharmacokinetic data available regarding prophylactic cefazolin dosing in obese pregnant women. We aimed to describe the plasma and interstitial fluid (ISF) pharmacokinetics of cefazolin in obese women undergoing elective cesarean delivery and use dosing simulations to predict optimal dosing regimens., Methods: Eligible women were scheduled for elective cesarean delivery at term, with a body mass index (BMI) of >35 kg·m. Plasma and ISF samples were collected following 2 g of intravenous cefazolin. Concentrations were determined using liquid chromatography-mass spectrometry. Population pharmacokinetic modeling and Monte Carlo dosing simulations were performed using Pmetrics. Total and unbound cefazolin concentrations in plasma and ISF were compared with the minimum inhibitory concentration at which 90% of isolates are inhibited (MIC90) of cefazolin for Staphylococcus aureus, 2 mg·L. The fractional target attainment (FTA) of dosing regimens to achieve a pre-established target of 95% unbound ISF concentrations >2 mg·L throughout a 3-hour duration of the surgery was calculated., Results: The 12 women recruited had a median (interquartile range [IQR]) BMI of 41.5 (39.7-46.6) kg·m and a median (IQR) gestation of 38.7 weeks (37.9-39.0). For each timepoint up to 180 minutes, the median across subjects of total and unbound plasma concentration of cefazolin remained above 2 mg·L. The minimum observed total plasma concentration was 31.7 mg·L and plasma unbound concentration was 7.7 mg·L (observed in the same participant). For each timepoint up to 150 minutes, the median across subjects of unbound ISF concentrations remained above 2 mg·L. The minimum observed unbound ISF concentration was 0.7 mg·L (observed in 1 participant). In 2 participants, the ISF concentration of cefazolin was not maintained above 2 mg·L. The mean (± standard error [SE]) penetration of cefazolin (calculated as area under the concentration-time curve for the unbound fraction of drug [fAUC]tissue/fAUCplasma) into the ISF was 0.884 ± 1.11. Simulations demonstrated that FTA >95% was achieved in patients weighing 90-150 kg by an initial 2 g dose with redosing of 2 g at 2 hours. FTA was improved to >99% when an initial 3 g dose was repeated at 2 hours., Conclusions: To maintain adequate ISF antibiotic concentrations in obese pregnant women, our results suggest that redosing of cefazolin may be required. When wound closure has not occurred within 2 hours, redosing is suggested, following either a 2 or 3 g initial bolus. These preliminary results require validation in a larger population.

Background: In the armamentarium of an anesthesiologist, videolaryngoscopy is a valuable addition to secure the airway. However, when the videolaryngoscope (VLS) offers no solution, few options remain. Earlier, we presented an intubation technique combining Macintosh blade VLS and Bonfils intubation endoscope (BIE) for a patient with a history of very difficult intubation. In the present study, we evaluated this technique to establish whether it is a valuable alternative., Methods: In this single-blinded nonrandomized study, 38 patients with a history of difficult intubation or 1 or more predictors of difficult intubation, scoring a Cormack & Lehane (C&L) grade III or IV using Macintosh blade VLS, were included. Patients were intubated combining the VLS with the BIE. The C&L grade was scored 3 times during (1) direct laryngoscopy; (2) indirect videolaryngoscopy; and (3) using the combined technique (VLS + BIE). Afterward, 2 blinded anesthesiologists assessed the C&L grade using the pictures taken during the procedure., Results: Data of 38 patients were analyzed. An improvement of the C&L grade with the combined technique occurred in 33 of 38 patients (86.8%; 95% confidence interval, 71.9%-95.6%). Reviewer 1 reported an improvement of the C&L grade with the combined technique in 37 of 38 patients. Reviewer 2 reported improvement in 33 and deterioration in 2 of the patients. No complications occurred., Conclusions: The combined use of a VLS with Macintosh blade and BIE gives the anesthesiologist a valuable alternative intubation option in patients with extremely difficult airways.

Background: The retention of nurse anesthetists is of paramount importance, particularly in view of the fact that the health care workforce is shrinking. Although many health care providers find their work satisfying, they often consider leaving their jobs because of the stress. Are there ways to improve this situation?, Purpose: This study investigated how work environment characteristics and personality dimensions relate to burnout and job satisfaction and ultimately to turnover intention among Dutch nurse anesthetists., Methodology: An online self-reporting questionnaire survey was performed among Dutch nurse anesthetists. The questionnaire included scales to assess personality dimensions, work climate, work context factors, burnout, job satisfaction, and turnover intention. The research model stated that personality dimensions, work climate, and work context factors, mediated by burnout and job satisfaction, predict turnover intention. Structural equation modeling was used to test the research model., Findings: Nine hundred twenty-three questionnaires were completed (46% response rate). Burnout mediated the relationship between personality dimensions and turnover intention; job satisfaction mediated the relationship of work climate and work context factors to turnover intention., Practice Implications: To retain nursing staff and to maintain adequate staff strength, it is important to improve job satisfaction by creating a positive work climate and work context and to prevent burnout by selecting the most suitable employees through personality assessment.

Background: Modern, video laryngoscopes provide an easier view of the glottis, possibly facilitating easier intubations. We describe an objective method for evaluating the benefits of video-assisted laryngoscopy, compared with standard techniques using force measurements., Method: Macintosh and video laryngoscopes (both Karl Storz, Tuttlingen, Germany) were used on the patients until the anesthesiologist was convinced he or she had the best possible view of the glottis. Actual intubation was only performed with the second of the laryngoscopes. Sensors measured the forces directly applied to the patients' maxillary incisors. Additionally, common subjective pre- (e.g., Mallampati) and intraintubation (e.g., Cormack-Lehane [C&L]) metrics of intubation difficulty were evaluated by the anesthesiologists., Results: All patients (24 female, [50 +/- 16 yr], 20 male [56 +/- 13 yr]) included in the study were successfully intubated with both the classic and video laryngoscopes. The forces recorded for the classic Macintosh blade ranged from 0 to 87.4 N with a median of 15.3 N, whereas the video laryngoscope forces ranged from 0 to 45.2 N, with a median of 2.1 N. The only factor determined to be significantly influential on the associated forces applied to the maxillary incisors was the laryngoscope type (P < 0.01). Video-assisted laryngoscopes reduced the applied forces over standard blades. Mallampati and C&L grade were not predictive of the forces applied., Conclusions: Video-assisted laryngoscopes seem beneficial when considering forces applied to the maxillary incisors as an objective metric of intubation difficulty. In this study, we could not support that Mallampati and C&L grades predict the forces that are applied to the maxillary incisors.

Purpose of Review: In today's anesthesia practice, provision of neuraxial anesthesia and analgesia is increasing. Along with the patient's fear of paralysis that accompanies placement of a needle near the spinal cord, any subsequent nerve deficit is usually blamed on the neuraxial block provided. Knowing the side effects from labor, neuraxial anesthesia or both is important as anesthesiologists are the first consultants to evaluate whenever a complication arises in these patients if there is a sensory or motor deficit in the lower extremities., Recent Findings: Neuraxial anesthesia may be associated with complaints of back pain, postdural puncture headache and severe complications (e.g., hematoma, abscess), but most complications following neuraxial blocks are associated with pregnancy and delivery, not the anesthetic. Signs and symptoms of the most common neurologic complications are described so that the clinician can promptly diagnose and treat these patients and seek appropriate consultation., Summary: Even though the incidence of true neurologic complications arising from neuraxial anesthesia is not known, they appear to be very rare. As anesthesiologists, providing care encompasses knowing the side effects and complications of the anesthetic we provide. Many of the nerve palsies that present in the postpartum patient may be of an obstetric origin, but anesthesiologists should be aware of anesthetic-related complications.

Purpose of Review: During the last few years, drug abuse has risen to the point that almost 20 million Americans are current abusers of illicit substances. These patients present to us as anesthesiologists in a variety of circumstances: in obstetrics for labor and emergencies, in trauma for emergency surgeries or life-saving (resuscitative) situations and in everyday elective surgeries. Therefore it is important for anesthesiologists to know about the most common illicit drugs being used, to know their side effects and clinical presentation if abused or intoxicated, and to know what anesthetic options would be beneficial or detrimental., Recent Findings: In this article we will review some of the most commonly used illicit drugs, their effects on the organ systems and some tips to take into consideration when providing anesthesia for these patients. We will discuss marijuana, cocaine, opioids, hallucinogens, solvents and the newer so-called rave or club drugs. Newer treatment options for opioid detoxification will also be discussed., Summary: Illicit substance abuse is a major health concern in the United States. Drug use, either acute or chronic, has potentially grave consequences which include changes affecting the pulmonary, cardiovascular, nervous, renal and hepatic systems. Anesthesiologists come into contact with these patients in emergency and everyday situations. Due to the diverse clinical presentations that may arise from single substance or polysubstance abuse, anesthetic management should be tailored to each individual and universal precautions should always be followed when providing care.

Background: The laryngeal mask airway LMA-Classic has been used widely in clinical practice. A new disposable supraglottic airway device, the Soft Seal LM, has been introduced recently. In a randomized study, the authors compared the LMA-Classic and the disposable Soft Seal LM in terms of their clinical performance, cuff pressures during nitrous oxide anesthesia, position of the laryngeal mask in situ by fiberoptic evaluation, and morbidity in a wide range of routine general surgery procedures., Methods: A total of 200 adult patients were randomly assigned to a size 4 laryngeal mask in two equal-sized groups for airway management during surgery: (1) LMA-Classic (Intavent Orthofix Ltd., Maidenhead, Berkshire, United Kingdom); or (2) Soft Seal LM (Portex Ltd., Hythe, Kent, United Kingdom). Anesthesia was administered with fentanyl, propofol, nitrous oxide, oxygen, and sevoflurane. The variables studied were ease of insertion, fiberoptic view, time in situ, incidence of blood on the laryngeal mask at the time of removal, and the incidence of postoperative sore throat at 2 and 24 h. The laryngeal mask cuff pressures were measured continuously. Intracuff pressure limitation was not attempted., Results: The LMA-Classic and the Soft Seal LM showed similar clinical performances, as shown by their insertion time (successful insertion at first attempt was achieved within 20 s in 97% with LMA-Classic trade mark vs. 95% with Soft Seal LM), fiberoptic evaluation of the anatomic position of the laryngeal mask, and satisfactory anesthesia conditions. Laryngeal mask cuff pressures increased from 45 to 100.3 mmHg in the LMA-Classic and from 45 to 46.8 mmHg in the Soft Seal LM (P < 0.001). Macroscopic blood was seen on only four occasions in the LMA-Classic group. The incidence of sore throat was significantly increased at 2 h postoperatively when using the LMA-Classic, although there was no difference at 24 h after surgery., Conclusions: In spontaneously breathing adult patients requiring a size 4 laryngeal mask airway, the new disposable Soft Seal LM device is an acceptable alternative to the reusable LMA-Classic trade mark, resulting in a good laryngeal seal and offering similar clinical performance. Cuff pressures increase substantially when the LMA-Classic is used but not when using the Soft Seal LM. There was less trauma to patients using the Soft Seal LM, as assessed by the incidence of sore throat in the early postoperative period.

An aqueous suspension of n-butyl-p-aminobenzoate (BAB), a highly lipid-soluble congener of benzocaine, was applied epidurally in terminally ill cancer patients with intractable pain. The suspension consisted of 10% BAB and 0.025% of the nonionic surfactant polysorbate 80 in 0.9% sodium chloride. Twelve consecutive patients received epidural BAB because pain was uncontrollable either by palliative radiotherapy or oral or epidural administrations of analgesics. The catheter or injecting needle was positioned at the segmental level of the pain. Repeated epidural injections were administered. In all patients, long-lasting sensory blockade (segmental analgesia) occurred, accompanied by a marked reduction or even absence of pain. In all patients, treatment with epidural opioids, alone or combined with local anesthetics, was no longer necessary. Five of the 12 patients did not require further administration of oral opioids. Motor, bowel, and bladder function were well preserved. In 6 patients, extensive necropsy of the spinal cord and spinal nerves did not reveal pathomorphologic changes. The outer aspect of the dura showed signs of focal necrosis on microscopy, yet its collagen structure and thickness were unchanged. Epidurally, focal infiltrative reactions were seen. The epidural use of an extremely lipid-soluble--hence hydrophobic--local anesthetic, with an exceptionally low pKa (2.3), formulated in suspension of the base, is conceptually innovative and needs further investigation. The authors conclude that the epidural administration of a BAB suspension may be an effective alternative to the neurolytic agents alcohol and phenol and may replace procedures such as cordotomy. Further investigation to determine the safety of BAB in this patient group appears warranted.

An aqueous suspension of n-butyl p-aminobenzoate (BAB), a highly lipid-soluble congener of benzocaine, was applied epidurally and around ulnar nerves in dogs. The suspension consisted of 10% BAB and 0.025% polysorbate in 0.9% NaCl. Sensory effects were tested by electrical stimulation. Three epidural injections were given, and the dogs were killed after 21 days. The increase in stimulation threshold was comparable to the effect of lidocaine in a concentration between 0.5% and 1%. Increased sensory threshold lasted for days, whereas no long-lasting motor effects were observed. Pathomorphologic changes were found primarily in the dorsal spinal nerve roots, although slight changes were also found in the ventral spinal roots. White matter degeneration was found only in the lumbar dorsal columns. This result suggested Wallerian degeneration in the dorsal spinal nerves and was at variance with recently published data on epidural BAB. No changes were observed in the ulnar nerves. The authors demonstrated that the pathomorphologic changes were induced by the BAB suspension and not by the suspending additive polysorbate 80. It was postulated that the suspension of BAB, which contains particles of a median size of 15 microns, was mainly confined to the dorsal epidural space where neurolytic changes in axons of the dorsal spinal nerve roots and dorsal columns are induced. This may explain the long-lasting sensory effects seen in intractable cancer pain patients after epidural BAB administration. More research is necessary to define the distribution of BAB in nervous tissue after its epidural administration and to better characterize toxicity, neurolytic effects, and regeneration of nervous tissue after BAB administrations.