Perioperative implications of sodium-glucose cotransporter-2 inhibitors: a case series of euglycemic diabetic ketoacidosis in three patients after cardiac surgery.

PURPOSE: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) comprise the newest class of oral hypoglycemic agents approved for treating type II diabetes mellitus (DM-II). Their use, however, has been associated with the rare development of euglycemic diabetic ketoacidosis (euDKA). We present three cases of euDKA that occurred following elective coronary artery bypass grafting surgery. The role of the anesthesiologist in the prevention, diagnosis, and management of this complication is also discussed. CLINICAL FEATURES: Three patients receiving chronic SGLT2i therapy for DM-II (discontinued one to two days preoperatively) underwent cardiac surgery. On the first postoperative day, each exhibited nausea, vomiting, and tachypnea. Although these nonspecific postoperative findings are common, our patients also exhibited anion gap metabolic acidosis (pH < 7.3, anion gap > 12 mmol·L-1) with lower than anticipated serum glucose levels of < 14 mmol·L-1. Serum and urine ketone analyses confirmed a diagnosis of euDKA. After insulin and dextrose infusions were initiated, rapid resolution of the metabolic abnormalities occured. CONCLUSIONS: Anesthesiologists should recognize that patients receiving SGLT2i preoperatively are at risk of developing euDKA. Hence, based on the pharmacokinetics of SGLT2i, discontinuing the medication at least two days prior to surgery should minimize the risk. Diagnosing euDKA is challenging and often delayed because of its nonspecific signs and symptoms. When suspected, serum and urine ketones should be monitored to reduce the time to diagnosis and treatment.

Effect of Dexamethasone in Peripheral Nerve Blocks on Recovery of Nerve Function.

BACKGROUND: Peripheral nerve blocks (PNBs) have revolutionized distal extremity surgery reducing pain and improving hospital efficiency. Perineural dexamethasone has been administered with PNBs to prolong their effects, although the safety of dexamethasone has not been established in the literature. This study aimed to determine if the addition of dexamethasone affected the postoperative neurological sensory status for foot and ankle surgeries and the recovery of nerve injuries. We hypothesized that the rate of persistent nerve injury would be higher in the dexamethasone group. METHODS: This is a retrospective observational cohort study of prospectively collected data of all patients from a single foot and ankle surgeon's practice. Perineural dexamethasone was routinely used as an adjunct by the regional anesthesia group until a clinical trend of increased paresthesia was found on short-term follow-up, which led to the discontinuation of its use. In this study, the cohort that received dexamethasone with ropivacaine was compared with the cohort that received ropivacaine alone. The primary outcome was a separate sensory nerve status sheet that was completed for every distal nerve territory for every patient at their follow-up visits at 2 weeks, 6 weeks, 3 months, and 6 months. Univariate analysis and a logistic regression model were used to determine the association between dexamethasone and delayed nerve recovery. A total of 250 patients were included in the study, with 117 patients in the dexamethasone group and 133 in the ropivacaine-only group. RESULTS: The rates of nerve injuries were not different between the groups (72 [62%] in the dexamethasone group vs 79 [59%] in the ropivacaine-only group). However, nerve injury symptoms were more likely to persist and not fully recover in the dexamethasone group (n = 47, 65%) compared with the ropivacaine-only group (n = 32, 41%) (OR, 2.12; P = .006). CONCLUSION: Perineural dexamethasone added to PNBs may be associated with delayed nerve recovery after foot and ankle surgery. It may be prudent to avoid its use until its full safety profile is established in larger prospective trials. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Accuracy of Physicians in Differentiating Type 1 and Type 2 Myocardial Infarction Based on Clinical Information.

BACKGROUND: Physicians commonly judge whether a myocardial infarction (MI) is type 1 (thrombotic) vs type 2 (supply/demand mismatch) based on clinical information. Little is known about the accuracy of physicians' clinical judgement in this regard. We aimed to determine the accuracy of physicians' judgement in the classification of type 1 vs type 2 MI in perioperative and nonoperative settings. METHODS: We performed an online survey using cases from the Optical Coherence Tomographic Imaging of Thrombus (OPTIMUS) Study, which investigated the prevalence of a culprit lesion thrombus based on intracoronary optical coherence tomography (OCT) in patients experiencing MI. Four MI cases, 2 perioperative and 2 nonoperative, were selected randomly, stratified by etiology. Physicians were provided with the patient's medical history, laboratory parameters, and electrocardiograms. Physicians did not have access to intracoronary OCT results. The primary outcome was the accuracy of physicians' judgement of MI etiology, measured as raw agreement between physicians and intracoronary OCT findings. Fleiss' kappa and Gwet's AC1 were calculated to correct for chance. RESULTS: The response rate was 57% (308 of 536). Respondents were 62% male; median age was 45 years (standard deviation ± 11); 45% had been in practice for > 15 years. Respondents' overall accuracy for MI etiology was 60% (95% confidence interval [CI] 57%-63%), including 63% (95% CI 60%-68%) for nonoperative cases, and 56% (95% CI 52%-60%) for perioperative cases. Overall chance-corrected agreement was poor (kappa = 0.05), consistent across specialties and clinical scenarios. CONCLUSIONS: Physician accuracy in determining MI etiology based on clinical information is poor. Physicians should consider results from other testing, such as invasive coronary angiography, when determining MI etiology.

CONTEXTE: Les médecins déterminent généralement s'ils sont en présence d'un infarctus du myocarde (IM) de type 1 (thrombotique) ou de type 2 (demande accrue ou apport réduit en oxygène) sur la base des renseignements cliniques. On en sait cependant très peu au sujet de la justesse du jugement clinique des médecins à cet égard. Nous avons donc cherché à déterminer si les médecins réussissent à distinguer correctement les IM de type 1 et de type 2 dans les contextes périopératoire et non opératoire. MÉTHODOLOGIE: Nous avons mené une enquête en ligne en utilisant les cas de l'étude OPTIMUS ( Op tical Coherence T omographic Im aging of Thromb us ), qui avait évalué la prévalence des lésions causant un thrombus au moyen de la tomographie par cohérence optique (TCO) endocoronaire chez les patients subissant un IM. Nous avons choisi au hasard quatre cas d'IM stratifiés en fonction de leur cause : deux cas en contexte périopératoire et deux cas en contexte non opératoire. Les médecins avaient accès aux antécédents médicaux, aux résultats des analyses de laboratoire et aux électrocardiogrammes des patients, mais pas aux résultats de la TCO endocoronaire. Le principal paramètre d'évaluation était la justesse du jugement du médecin concernant la cause de l'IM, mesurée en fonction de la concordance approximative entre le jugement du médecin et les observations à la TCO endocoronaire. Les coefficients de concordance kappa de Fleiss et AC1 de Gwet ont servi à corriger pour le hasard. RÉSULTATS: Le taux de réponse était de 57 % (308 sur 536). Des participants, 62 % étaient des hommes et 45 % exerçaient depuis plus de 15 ans; l'âge médian était de 45 ans (écart-type : ± 11). La justesse globale avec laquelle les répondants ont déterminé la cause des IM était de 60 % (intervalle de confiance [IC] à 95 % : 57-63 %) : 63 % (IC à 95 % : 60-68 %) dans le cas des IM en contexte non opératoire et 56 % (IC à 95 % : 52-60 %) dans le cas des IM en contexte périopératoire. La concordance globale corrigée pour le hasard était faible (kappa = 0,05) et demeurait constante, sans égard au domaine de spécialité ou au scénario clinique. CONCLUSIONS: La justesse du jugement des médecins évaluant la cause d'un IM en fonction des renseignements cliniques est faible. Les médecins devraient envisager de recourir à des tests additionnels, y compris la coronarographie invasive, avant de déterminer la cause d'un IM.

Short-term results of transapical transcatheter mitral valve implantation for mitral regurgitation.

BACKGROUND: Mitral regurgitation (MR) is the most common valvular heart disease, and mitral valve surgery is the gold standard therapy for severe MR. Many patients with severe MR are not referred for surgery because of old age, comorbidities, or severe left ventricular dysfunction. Transcatheter mitral valve implantation may be a better therapeutic option for these high-risk patients with severe symptomatic MR. OBJECTIVES: This study sought to describe the first-in-man series of transapical mitral valve implantation for mitral regurgitation with the TIARA device. METHODS: Extensive preclinical ex vivo and animal studies were conducted with the transapical mitral valve implantation of the Tiara system. The first 2 cases of human implantation were successfully performed in a 73-year-old man and a 61-year-old woman with severe functional MR. Both patients were in New York Heart Association class IV heart failure with depressed left ventricular ejection fraction, pulmonary hypertension, and additional comorbidities. RESULTS: The valve was implanted uneventfully in both patients. General anesthesia and transapical access were used. Patients were hemodynamically stable with no need for cardiopulmonary bypass. Immediately after implantation, systemic arterial pressure and stroke volume increased and pulmonary pressure decreased dramatically. There were no intraoperative complications, and both patients were extubated in the operating room. Post-procedural echocardiograms at 48 h, 1 month, and 2 months demonstrated excellent prosthetic valve function with a low transvalvular gradient and no left ventricular outflow tract obstruction. There was a trivial paravalvular leak in the first patient at 48 h, which was completely resolved at subsequent studies; no paravalvular leak occurred in the second patient. CONCLUSIONS: Transapical transcatheter mitral valve implantation is technically feasible and can be performed safely. Early hemodynamic performance of the prosthesis was excellent. Transcatheter mitral valve implantation may become an important treatment option for patients with severe MR who are at high operative risk.

Transcatheter aortic valve replacement.

Aortic stenosis is one of the most common valve pathologies found in adults. Aortic valve replacement via a sternotomy and cardiopulmonary bypass is the treatment of choice for patients with symptomatic aortic stenosis with very acceptable risk. However, patients with advanced age and multiple comorbidities carry significant operative risk; operative mortality as high as 25% was reported by many groups. Many of these patients are deemed nonsurgical for conventional aortic valve replacement by their cardiologists and surgeons. Novel surgical technique and valve technology offers an alternative treatment for aortic valve stenosis. Endovascular transcatheter aortic valve replacement is an emerging and promising technique, and may lower the risk in this subset of difficult patients.

Canadian pediatric anesthesiologists prefer inhalational anesthesia to manage difficult airways.

PURPOSE: To survey Canadian pediatric anesthesiologists to assess practice patterns in managing pediatric patients with difficult airways. METHODS: Canadian pediatric anesthesiologists were invited to complete a web survey. Respondents selected their preferred anesthetic and airway management techniques in six clinical scenarios. The clinical scenarios involved airway management for cases where the difficulty was in visualizing the airway, sharing the airway and accessing a compromised airway. RESULTS: General inhalational anesthesia with spontaneous respiration was the preferred technique for managing difficult intubation especially in infants (90%) and younger children (97%), however, iv anesthesia was chosen for the management of the shared airway in the older child (51%) where there was little concern regarding difficulty of intubation. Most respondents would initially attempt direct laryngoscopy for the two scenarios of anticipated difficult airway (73% and 98%). The laryngeal mask airway is commonly used to guide fibreoptic endoscopy. The potential for complete airway obstruction would encourage respondents to employ a rigid bronchoscope as an alternate technique (17% and 44%). CONCLUSION: Inhalational anesthesia remains the preferred technique for management of the difficult pediatric airway amongst Canadian pediatric anesthesiologists. Intravenous techniques are relatively more commonly chosen in cases where there is a shared airway but little concern regarding difficulty of intubation. In cases of anticipated difficult intubation, direct laryngoscopy remains the technique of choice and fibreoptic laryngoscopy makes a good alternate technique. The use of the laryngeal mask airway was preferred to facilitate fibreoptic intubation.