Intraoperative Fascial Plane Blocks Facilitate Earlier Tracheal Extubation and Intensive Care Unit Discharge After Cardiac Surgery: A Retrospective Cohort Analysis.

OBJECTIVES: Novel fascial plane blocks may allow early tracheal extubation and discharge from the intensive care unit (ICU). The present study primarily aimed to determine whether fascial plane blocks, in comparison with intravenous analgesia alone, significantly shortened tracheal extubation times in patients undergoing cardiac surgery. The secondary objectives were to compare each block's performance with that of intravenous analgesia alone in terms of the individual tracheal extubation time and length of ICU stay. DESIGN: Retrospective observational study. SETTING: Single-center study. PARTICIPANTS: Patients who underwent cardiac surgery between 2018 and 2019 were identified from a prospective clinical registry. After obtaining ethics approval, the clinical and electronic records of patients undergoing cardiac surgery in 2018 were analyzed. Data of patients receiving fascial plane blocks (erector spinae plane [ESP], pectoral plane I and II [PECs], and serratus anterior plane [SAP] blocks) with intravenous analgesia were compared with those of patients receiving only intravenous analgesia. A propensity score (PS) model was used to control for differences in the baseline characteristics. Adjusted p < 0.05 was considered statistically significant. MEASUREMENTS AND MAIN RESULTS: Of the 589 patients screened, 532 met the inclusion criteria; 404 received a fascial plane block. After PS matching, weighted linear regression revealed that by receiving a block, the predicted extubation time difference was 9.29 hours (b coefficient; 95% CI: -11.98, -6.60; p = 0.022). Similar results were obtained using PS weighting, with a reduction of 7.82 hours (b coefficient; 95% CI: -11.89, -3.75; p < 0.001) in favor of the block. In the fascial-plane-block group, ESP block achieved the best performance. The length of ICU stay decreased by 1.1 days (b coefficient; 95% CI: -1.43, -0.79; p = 0.0001) in the block group. No complications were reported. CONCLUSIONS: Fascial plane block is associated with reduced extubation times and lengths of ICU stay. ESP block achieved the best performance, followed by PECs and SAP blocks. After PS matching, only ESP block reduced the extubation time.

Efecto del fentanilo intratecal en hiperlagesia secundaria posoperatoria de cirugía ligamento cruzado anterior de rodilla / Effect of Intrathecal fentanyl on secondary hyperalgesia, in patients undergoing anterior cruciate ligament repair

BACKGROUND AND OBJECTIVES: Fentanyl addition is a common practice when administering spinal anesthesia. Intrathecal fentanyl has been associated to increased postoperative pain and increase morphine consumption, but considered to be related to acute opioid tolerance. This prospective, randomized, blind study evaluates the effect of intrathecal fentanyl in the development of secondary hyperalgesia, measured with Von Frey filaments, in patients undergoing anterior cruciate ligament repair. METHODS: 46 patients having anterior cruciate ligament repair, received intrathecal hyperbaric bupivacaine 13.5 mg with fentanyl 20 mcg or no fentanyl addition. Light touch pain threshold was measured with von Frey filaments before anesthesia, at 6 and 24 hours post anesthesia in the non-operated thigh and in the forearm. Visual analogue pain scores and morphine consumption were also measured at the same time. RESULTS: Baseline thresholds to mechanical stimuli were similar in both groups. In the forearm, analysis showed a decreased threshold for the non-fentanyl group at 24 h p = 0.036. In the lower extremity, control and treatment group showed lower thresholds (secondary hyperalgesia) p = 0.002 but no difference between them p = 0.795. VAS score and morphine consumption did not differ among groups. CONCLUSIONS: Spinal fentanyl added to hyperbaric bupivacaine showed no evidence of an augmented state of hyperalgesia after ACL repair, neither by pain threshold modification nor clinical outcomes. On the contrary, at 24 h, fentanyl may have a protective effect at levels above the spinal block.

ANTECEDENTES Y OBJETIVOS: El uso de fentanilo es una práctica común en la administración de anestesia espinal. Su aplicación se ha asociado a un aumento del dolor post operatorio y a un aumento en el uso de morfina; por otro lado, se ha vinculado a una tolerancia aguda a opioides. El siguiente estudio prospectivo, randomizado y ciego, evalúa los efectos del fentanilo intratecal en la aparición de hiperalgesia secundaria, medida a través de filamentos Von Frey, en pacientes operados de ligamento cruzado anterior. METODOLOGÍA: Se incluyeron a 46 pacientes operados de ligamento cruzado anterior (LCA) con una dosis intratecal de bupivacaína hiperbárica de 13,5 mg; con y sin la adición de fentanilo de 20 mcg. Se midió el umbral del dolor mecánico, a través de filamentos Von Frey, antes de la anestesia, a las 6 y 24 horas postanestesia en el muslo no operado y en el antebrazo. Al mismo tiempo, se midió la puntuación del dolor en la escala verbal numérica (EVN) y el consumo de morfina. RESULTADOS: Los umbrales basales ante la estimulación mecánica resultaron similares en ambos grupos. En el antebrazo, el análisis mostró una disminución del umbral en el grupo de pacientes sin fentanilo, a las 24 h, p = 0,036 comparado con uso de fentanilo. En el muslo, el grupo control y tratamiento mostró umbrales más bajos (hiperalgesia secundaria) p = 0,002; no obstante, no se mostraron diferencias entre ellos. No se mostraron diferencias entre las puntuaciones de la EVN y el consumo de morfina en los dos grupos. CONCLUSIÓN: No hay evidencia que la adición de fentanilo espinal, a la dosis de bupivacaína hiperbárica, haya contribuido a un aumento en la hiperalgesia tras la reparación del LCA, medido por la modificación del umbral del dolor, ni en los resultados clínicos. Al contrario a las 24 h fentanilo puede tener un efecto protector de la hiperalgesia secundaria sobre el nivel del bloqueo espinal.

Perioperative lumbar plexus block and cardiac ischemia in patients with hip fracture: randomized clinical trial / Bloqueio perioperatório do plexo lombar e isquemia cardíaca em pacientes com fratura de quadril: ensaio clínico randomizado

Abstract Background Perioperative myocardial ischemia is common among patients undergoing hip fracture surgery. Our aim is to evaluate the efficacy of perioperative continuous lumbar plexus block in reducing the risk of cardiac ischemic events of elderly patients undergoing surgery for hip fractures, expressed as a reduction of ischemic events per subject. Methods Patients older than 60 years, ASA II-III, with risk factors for or known coronary artery disease were enrolled in this randomized controlled study. Patients were randomized to conventional analgesia using opioid intravenous patient-controlled analgesia or continuous lumbar plexus block analgesia, both started preoperatively and maintained until postoperative day three. Continuous electrocardiogram monitoring with ST segment analysis was recorded. Serial cardiac enzymes and pain scores were registered during the entire period. We measured the incidence of ischemic events per subject registered by a continuous ST-segment Holter monitoring. Results Thirty-one patients (intravenous patient-controlled analgesia 14, lumbar plexus 17) were enrolled. There were no major cardiac events during the observation period. The number of ischemic events recorded by subject during the observation period was 6 in the lumbar plexus group and 3 in the intravenous patient-controlled analgesia group. This difference was not statistically significant (p = 0.618). There were no statistically significant differences in the number of cases with increased perioperative troponin values (3 cases in the lumbar plexus group and 1 case in the intravenous patient-controlled analgesia group) or in terms of pain scores. Conclusions Using continuous perineural analgesia, compared with conventional systemic analgesia, does not modify the incidence of perioperative cardiac ischemic events of elderly patients with hip fracture.

Resumo Justificativa A isquemia miocárdica perioperatória é comum em pacientes submetidos à cirurgia de fratura de quadril. Nosso objetivo foi avaliar a eficácia do bloqueio perioperatório contínuo do plexo lombar na redução do risco de eventos cardíacos isquêmicos em pacientes idosos submetidos à cirurgia para fraturas de quadril, expresso como uma redução de eventos isquêmicos por indivíduo. Métodos Pacientes com mais de 60 anos de idade, ASA II-III com fatores de risco para ou com doença coronariana conhecida foram incluídos neste estudo controlado e randomizado. Os pacientes foram aleatorizados para analgesia convencional usando analgésicos opioides para administração de analgesia intravenosa controlada pelo paciente (Intravenous Patient-Controlled Analgesia - IVPCA) ou analgesia contínua com o bloqueio do Plexo Lombar (PL), ambas iniciadas no pré-operatório e mantidas até o terceiro dia de pós-operatório. Monitoração contínua de ECG com análise do segmento ST foi registrada. Enzimas cardíacas seriadas e escores de dor foram registrados durante todo o período. Medimos a incidência de eventos isquêmicos por indivíduo registrados com monitoração contínua do segmento ST via Holter. Resultados Trinta e um pacientes (IVPCA 14, PL 17) foram incluídos. Não houve eventos cardíacos sérios durante o período de observação. O número de eventos isquêmicos registrados por sujeito durante o período de observação foi de seis no grupo PL e três no grupo IVPCA. Essa diferença não foi estatisticamente significativa (p = 0,618). Não houve diferenças estatisticamente significativas no número de casos com aumento dos valores de troponina no perioperatório (três casos no grupo LP e um caso no grupo IVPCA) ou em termos de escores de dor. Conclusões O uso da analgesia perineural contínua comparado ao da analgesia sistêmica convencional não modifica a incidência de eventos isquêmicos cardíacos no período perioperatório de pacientes idosos com fratura de quadril.

[Perioperative lumbar plexus block and cardiac ischemia in patients with hip fracture: randomized clinical trial]. / Bloqueio perioperatório do plexo lombar e isquemia cardíaca em pacientes com fratura de quadril: ensaio clínico randomizado.

BACKGROUND: Perioperative myocardial ischemia is common among patients undergoing hip fracture surgery. Our aim is to evaluate the efficacy of perioperative continuous lumbar plexus block in reducing the risk of cardiac ischemic events of elderly patients undergoing surgery for hip fractures, expressed as a reduction of ischemic events per subject. METHODS: Patients older than 60 years, ASA II-III, with risk factors for or known coronary artery disease were enrolled in this randomized controlled study. Patients were randomized to conventional analgesia using opioid intravenous patient-controlled analgesia or continuous lumbar plexus block analgesia, both started preoperatively and maintained until postoperative day three. Continuous electrocardiogram monitoring with ST segment analysis was recorded. Serial cardiac enzymes and pain scores were registered during the entire period. We measured the incidence of ischemic events per subject registered by a continuous ST-segment Holter monitoring. RESULTS: Thirty-one patients (intravenous patient-controlled analgesia 14, lumbar plexus 17) were enrolled. There were no major cardiac events during the observation period. The number of ischemic events recorded by subject during the observation period was 6 in the lumbar plexus group and 3 in the intravenous patient-controlled analgesia group. This difference was not statistically significant (p=0.618). There were no statistically significant differences in the number of cases with increased perioperative troponin values (3 cases in the lumbar plexus group and 1 case in the intravenous patient-controlled analgesia group) or in terms of pain scores. CONCLUSIONS: Using continuous perineural analgesia, compared with conventional systemic analgesia, does not modify the incidence of perioperative cardiac ischemic events of elderly patients with hip fracture.

World Health Organization (WHO) surgical safety checklist implementation and its impact on perioperative morbidity and mortality in an academic medical center in Chile.

Health care organizations are unsafe. Numerous centers have incorporated the WHO Surgical Safety Checklist in their processes with good results; however, only limited information is available about its effectiveness in Latin America. We aimed to evaluate the impact of the checklist implementation on the in-hospital morbidity and mortality rate in a tertiary health care center. After Institutional review board approval, and using data from our hospital administrative records, we conducted a retrospective analysis of all surgical encounters (n = 70,639) over the period from January 2005 to December 2012. Propensity scoring (PS) methods (matching and inverse weighting) were used to compare the pre and postintervention period, after controlling for selection bias. After PS matching (n = 29,250 matched pairs), the in-hospital mortality rate was 0.82% [95% confidence interval (CI), 0.73-0.92] before and 0.65% (95% CI, 0.57-0.74) after checklist implementation [odds ratio (OR) 0.73; 95% CI, 0.61-0.89]. The median length of stay was 3 days [interquartile range (IQR), 1-5] and 2 days (IQR, 1-4) for the pre and postchecklist period, respectively (P < 0.01).This is the first Latin American study reporting a decrease in mortality after the implementation of the WHO Surgical Checklist in adult surgical patients. This is a strong and simple tool to make health care safer, especially in developing countries.

Which types of peripheral nerve blocks should be included in residency training programs?

BACKGROUND: Despite the increasing use of regional anesthesia, specific recommendations regarding the type of procedures to be included in residency training programs are not currently available. We aimed to determine the nerve block techniques that practicing Chilean anesthesiologists perceived as essential to master during residency training. METHODS: After institutional ethics committee approval, an online survey was sent to 154 anesthesiologists that graduated between 2005-2012, from the two largest university residency programs in Chile. Multiple-choice questions elicited responses concerning the use of regional anesthesia. RESULTS: A total of 109 questionnaires were completed, which corresponded to a response rate of 70.8%. Almost all (98.2%) of the respondents used regional anesthesia in their clinical practice, 86.7% regularly performed peripheral nerve blocks (PNBs) and 51% used continuous PNB techniques. Residency programs represented their primary source of training. The most common PNB techniques performed were interscalene (100%), femoral (98%), popliteal sciatic (93%), and Bier block (90%). Respondents indicated that they were most confident performing femoral (98%), Bier block (90%), interscalene (90%), and popliteal sciatic (85%) blocks. The PNBs perceived as essential for their actual clinical practice were femoral (81%), interscalene (80%), popliteal sciatic (76%), and Bier blocks (62%). CONCLUSIONS: Requesting information from former anesthesiology residents may be a source of information, guiding the specific types of PNBs that should be included in residency training. Other groups can easily replicate this methodology to create their own evidence and clinical practice based guidelines for residency training programs.

The relationship between neuraxial anesthesia and advanced ovarian cancer-related outcomes in the Chilean population.

BACKGROUND: Mixed evidence has been published relating the use of regional anesthesia during oncologic surgery to a decrease in time to cancer recurrence and improvement in overall survival. We investigated whether the use of epidural anesthesia, in addition to general analgesia during and/or after surgical removal of advanced ovarian cancer, has an impact on time to recurrence and overall survival. METHODS: Patients were identified from a prospective clinical registry. Eighty patients with advanced ovarian cancer (International Federation of Gynecologists and Obstetricians, stage IIIC and IV) undergoing surgery between January 2000 and March 2011 were studied. Propensity scoring (PS) methods (matching and inverse weighting) were used to compare the time to recurrence and overall survival of patients who did and did not receive epidural anesthesia and/or analgesia (EA), after controlling for selection bias. RESULTS: The median time to recurrence was 1.6 and 0.9 years for the EA and no EA groups, respectively (P = 0.02). After PS matching, the median time to recurrence was 1.6 and 1.4 years for the EA and no EA groups, respectively (P = 0.30). Similarly, PS weighting did not demonstrate an improvement in time to recurrence with the use of EA. Using a Cox proportional hazards model in the PS-matched sample, the estimated hazard ratio for EA exposure (0.72; 95% confidence interval [CI], 0.40-1.33) did not change substantially after adjusting for chemotherapy (0.73; 95% CI, 0.40-1.31). Similar results were obtained using PS weighting. The median survival time was 3.3 and 1.9 years for the EA and no EA groups, respectively (P = 0.01). After PS matching, the median survival time was 3.3 and 2.7 years for the EA and no EA groups, respectively (P = 0.37). Similarly, PS weighting did not demonstrate an improved survival with the use of EA. The estimated hazard ratio (0.74; 95% CI, 0.36-1.49) in the PS matched sample did not change substantially after adjusting for chemotherapy, with similar results when PS weighting was applied. CONCLUSIONS: After PS matching and weighting, we found no benefit in overall survival or time to recurrence in patients with advanced stages (International Federation of Gynecologists and Obstetricians IIIC and IV) of ovarian cancer after the use of EA during and after tumor debulking surgery.

Comparison of plasma concentrations of levobupivacaine with and without epinephrine for transversus abdominis plane block.

BACKGROUND AND OBJECTIVES: The pharmacokinetics for levobupivacaine in transversus abdominis plane (TAP) blocks has not been previously reported. We aimed to determine the extent of the block and the effect on plasma concentrations of levobupivacaine with the addition of epinephrine. METHODS: We enrolled 11 healthy volunteers in this double-blind, 2-intervention, 2-period crossover study. The intervention periods were defined as a unilateral left TAP block with 20 mL of 0.25% levobupivacaine with (E) or without (no E) 5 µg/mL epinephrine. Subjects were randomized to E, followed by no E or no E followed by E, with 2-week washout period. Sensory dermatomal anesthesia was recorded. Blood samples were obtained for the measurement of plasma levobupivacaine levels. RESULTS: The median cranial-to-caudal spread of sensory blockade for sharp touch was T9 (interquartile range [IQR], T7-T10) to L1 (IQR, T12-L1) with epinephrine and T9 (IQR, T8-T10) to T12 (IQR, T11-L1) without epinephrine (P > 0.05). The mean maximum arterial levobupivacaine concentrations with epinephrine were 0.36 (95% bootstrap confidence interval [95% CI], 0.30-0.42) µg/mL and 0.63 (95% CI, 0.49-0.85) µg/mL without epinephrine (P = 0.014, difference in means of 0.27 [95% CI, 0.12-0.46]). The mean maximal venous levobupivacaine concentration was 0.32 (95% CI, 0.28-0.39) µg/mL and 0.49 (95% CI, 0.37-0.68) µg/mL, with and without epinephrine, respectively (P = 0.006, difference in means of 0.17 [95% CI, 0.08-0.33]). The mean duration of the blockade was 10.2 hours (95% CI, 8.5-12.5 hours) with epinephrine and 10.3 hours (95% CI, 8.7-12.4 hours) without epinephrine (P = 1.000). CONCLUSIONS: Adding epinephrine to levobupivacaine reduces its peak plasma concentration after unilateral TAP blocks, with no remarkable effects on block characteristics or duration.

The effective effect-site propofol concentration for induction and intubation with two pharmacokinetic models in morbidly obese patients using total body weight.

BACKGROUND: Most pharmacokinetic (PK) models used for propofol administration are based on studies in normal-weight patients. Extrapolation of these models for morbidly obese patients is controversial. Using 2 PK models and a target-controlled infusion system, we determined the predicted propofol effect-site concentration (Ce) needed for induction of anesthesia in morbidly obese subjects using total body weight. METHODS: Sixty-six morbidly obese subjects from 18 to 50 years of age were randomized to receive propofol to reach and maintain a predetermined propofol Ce, based on the PK models of either Marsh or Schnider. All patients were monitored with a Bispectral Index electroencephalographic monitor. Fentanyl 3 µg/kg total body weight was administered before starting the propofol infusion. After loss of consciousness, vecuronium was administered to facilitate endotracheal intubation. Groups of 6 patients each received propofol at a different, predetermined target propofol Ce. An "effective Ce" (ECe) was defined as the propofol Ce that provided adequate hypnosis (Bispectral Index <60) during the complete induction period (45 seconds after reaching the predetermined target Ce until 5 minutes after tracheal intubation). Heart rate and arterial blood pressure were measured every 1 minute throughout the study period. Probit regression analysis was performed to calculate the effective propofol Ce values to induce hypnosis in 50% (ECe(50)) and 95% (ECe(95)) of patients with 95% confidence intervals (CIs). RESULTS: Patient characteristics were similar between models and across the propofol target concentration groups. The ECe(50) of propofol was 3.4 µg/mL (95% CI: 2.9, 3.7 µg/mL) with the Marsh model and 4.5 µg/mL (95% CI: 4.1, 4.8 µg/mL) with the Schnider model (P < 0.001). The ECe(95) values were 4.2 µg/mL (95% CI: 3.8, 6.2 µg/mL) and 5.5 µg/mL (95% CI: 5.0, 7.2 µg/mL) with Marsh and Schnider models, respectively. At the ECe(95), hemodynamic effects were similar with the 2 PK models. CONCLUSION: Different propofol target concentrations for each PK model must be used for induction when using total body weight in morbidly obese patients.

[Effects on blood glucose of prophylactic dexamethasone for postoperative nausea and vomiting in diabetics and non-diabetics]. / Dexametasona para profilaxis de náuseas y vómitos postoperatorios: efecto sobre la glicemia en pacientes con diabetes mellitus tipo 2 y en no diabéticos sometidos a cirugía laparoscópica.

BACKGROUND: Postoperative nausea and vomiting (PONV) prophylaxis with dexamethasone may produce significant hyperglycemia in the postoperative period. AIM: To evaluate if this effect is of greater severity in type 2 diabetics compared with non-diabetic patients. MATERIAL AND METHODS: Forty non-diabetic and thirty type 2 diabetic patients undergoing laparoscopic cholecystectomy were studied in a prospective and double-blind fashion manner. Patients were randomly distributed into 4 groups: Group I, non-diabetics control (n = 20), Group II, non-diabetics dexamethasone (n = 20), Group III, type 2 diabetics control (n = 15), and Group IV, type 2 diabetics dexamethasone (n = 15). Immediately after induction, patients in groups I and III received isotonic saline and patients in the dexamethasone groups received 8 mg i.v. of the steroid. Capillary blood glucose concentrations were measured at baseline and every 2 hours during the first 12 hours since the start of surgery. A linear mixed effect model, adjusted for baseline capillary glucose concentration, age and duration of surgery was used to analyze the data. RESULTS: No effect of the presence of diabetes mellitus was observed in the evolution of glucose concentrations. There was a difference in capillary glucose concentrations between patients who received dexamethasone and placebo that started 2 hours post-intervention, reaching a mean maximum difference of 34 mg/dl (adjusted model, p < 0.001) at 10 hours post-intervention. CONCLUSIONS: In this study, Type 2 diabetic patients did not show a higher susceptibility than non-diabetics to develop postoperative hyperglycemia after the use of prophylactic dexamethasone for PONV.

Dexametasona para profilaxis de náuseas y vómitos postoperatorios: efecto sobre la glicemia en pacientes con diabetes mellitus tipo 2 y en no diabéticos sometidos a cirugía laparoscópica / Effects on blood glucose of prophylactic dexamethasone for postoperative nausea and vomiting in diabetics and non-diabetics

Background: Postoperative nausea and vomiting (PONV) prophylaxis with dexamethasone may produce significant hyperglycemia in the postoperative period. Aim: To evaluate if this effect is of greater severity in type 2 diabetics compared with non-diabetic patients. Material and Methods: Forty non-diabetic and thirty type 2 diabetic patients undergoing laparoscopic cholecystectomy were studied in a prospective and double-blind fashion manner. Patients were randomly distributed into 4 groups: Group I, non-diabetics control (n = 20), Group II, non-diabetics dexamethasone (n = 20), Group III, type 2 diabetics control (n = 15), and Group I V, type 2 diabetics dexamethasone (n = 15). Immediately after induction, patients in groups I and III received isotonic saline and patients in the dexamethasone groups received 8 mg iv of the steroid. Capillary blood glucose concentrations were measured at baseline and every 2 hours during the first 12 hours since the start of surgery. A linear mixed effect model, adjusted for baseline capillary glucose concentration, age and duration of surgery was used to analyze the data. Results: No effect of the presence of diabetes mellitus was observed in the evolution of glucose concentrations. There was a difference in capillary glucose concentrations between patients who received dexamethasone and placebo that started 2 hours post-intervention, reaching a mean maximum difference of 34 mg/dl (adjusted model, p < 0.001) at 10 hours post-intervention. Conclusions: In this study, Type 2 diabetic patients did not show a higher susceptibility than non-diabetics to develop postoperative hyperglycemia after the use of prophylactic dexamethasone for PONV.