Corrigendum to "Pregabalin Effect on Acute and Chronic Pain after Cardiac Surgery".

[This corrects the article DOI: 10.1155/2017/2753962.].

Do Difficult Airway Techniques Predispose Obese Patients to Bronchospasm?

OBJECTIVE: The existing evidence separately correlates morbid obesity with difficult intubation and bronchospasm. However, there is a lack of data on whether anaesthesia provider manipulations during difficult intubation contribute to an increased ratio of bronchospasm in these patients. METHODS: This is a retrospective analysis of data prospectively taken from 50 morbidly obese patients involved in a previously published study. A possible difficult intubation was preoperatively investigated by recording the following specific physical examination indices: Mallampati and Cormack-Lehane (CL) classifications, cervical spine mobility (CSM), thyromental distance (Td) and patients' ability to open their mouth (mouth opening). Bronchospasm was clinically detected by auscultation and confirmed by measuring peak airway pressures during mechanical ventilation. The Kruskal-Wallis H test was used for data analysis, followed by the Mann-Whitney U test as applicable. RESULTS: Different physical examination prognostic indices, including Mallampati and CL scales (p<0.001; the CSM excluded -p=0.790), showed that they are related to difficult intubation. Bronchospasm not attributable to difficult intubation was observed in six obese patients. CONCLUSION: Patients with morbid obesity constitute an increased relative risk group as far as difficult intubation is concerned, particularly if preoperative findings support a relationship between the two variables examined. In our study, difficult intubation and the concomitant use of special equipment and manipulations did not contribute to an increased rate of bronchospasm in obese patients, but in view of the lack of data, a large number of more sophisticated studies are required to elucidate such an assumption.

Superior perioperative analgesia with combined femoral-obturator-sciatic nerve block in comparison with posterior lumbar plexus and sciatic nerve block for ACL reconstructive surgery.

PURPOSE: The purpose of this randomized controlled study is to compare and evaluate the intraoperative and post-operative outcome of PLPS nerve block and that of femoral, obturator and sciatic (FOS) nerve block as a method of anaesthesia, in performing ACL reconstruction. METHODS: Patients referred for elective arthroscopic ACL reconstruction using hamstring autograft were divided in two groups. The first group received combined femoral-obturator-sciatic nerve block (FOS Group) under dual guidance, whereas the second group received posterior lumbar plexus block under neurostimulation and sciatic nerve block (PLPS Group) under dual guidance. RESULTS: The two groups were comparable in terms of age, sex, BMI and athletic activity. The time needed to perform the nerve blocks was significantly shorter for the FOS group (p < 0.005). Similarly, VAS scores during tourniquet inflation and autograft harvesting were significantly higher (p < 0.005) in the PLPS group and this is also reflected in the intraoperative fentanyl consumption and conversion to general anaesthesia. Finally, patients in this group also reported higher post-operative VAS scores and consumed more morphine. CONCLUSIONS: Peripheral nerve blockade of FOS nerve block under dual guidance for arthroscopic ACL reconstructive surgery is a safe and tempting anaesthetic choice. The success rate of this technique is higher in comparison with PLPS and results in less peri- and post-operative pain with less opioid consumption. This study provides support for the use of peripheral nerve blocks as an exclusive method for ACL reconstructive surgery in an ambulatory setting with almost no complications. LEVEL OF EVIDENCE: I.

Pregabalin Effect on Acute and Chronic Pain after Cardiac Surgery.

Introduction. Pain after cardiac surgery affects long-term patient wellness. This study investigated the effect of preoperative pregabalin on acute and chronic pain after elective cardiac surgery with median sternotomy. Methods. Prospective double blind study. 93 cardiac surgery patients were randomly assigned into three groups: Group 1 received placebo, Group 2 received oral pregabalin 75 mg, and Group 3 received oral pregabalin 150 mg. Data were collected 8 hours, 24 hours, and 3 months postoperatively. Results. Patients receiving pregabalin required fewer morphine boluses (10 in controls versus 6 in Group 1 versus 4 in Group 2, p = 0.000) and had lower pain scores at 8 hours (4 versus 3 versus 3, p = 0.001) and 3 months (3 versus 2 versus 2, p = 0.000) and lower morphine consumption at 8 hours (14 versus 13 versus 12 mg, p = 0.000) and 24 hours (19.5 versus 16 versus 15 mg, p = 0.000). Percentage of patients with sleep disturbances or requiring analgesics was lower in the pregabalin group and even lower with higher pregabalin dose (16/31 versus 5/31 versus 3/31, p = 0.000, and 26/31 versus 16/31 versus 10/31, p = 0.000, resp.) 3 months after surgery. Conclusion. Preoperative oral pregabalin 75 or 150 mg reduces postoperative morphine requirements and acute and chronic pain after cardiac surgery.

Spinal versus general anesthesia for transabdominal preperitoneal (TAPP) repair of inguinal hernia: Interim analysis of a controlled randomized trial.

BACKGROUND: General anesthesia has been used as standard for laparoscopic hernia repair by the transabdominal preperitoneal (TAPP) approach. Regional anesthesia has been occasionally applied in high risk patients where general anesthesia is contraindicated. This randomized clinical trial compares spinal anesthesia with general anesthesia for TAPP inguinal hernia repair in non-high risk patients. METHODS: Seventy adult American Society of Anesthesiologists I, II and III patients undergoing elective TAPP inguinal hernia repair were randomized to either general or spinal anesthesia. RESULTS: Postoperative morphine consumption was significantly less immediately postoperatively (p < 0.001) in the spinal anesthesia group. Postoperative pain was also significantly decreased within the first 8 h postoperatively (p < 0.05) in the spinal anesthesia group. CONCLUSIONS: Spinal anesthesia offers some advantages in patient analgesia during the early postoperative period after TAPP inguinal hernia repair and can be proposed as an effective alternative method of anesthesia for TAPP repair.

Bronchospasm in obese patients undergoing elective laparoscopic surgery under general anesthesia.

BACKGROUND: Existing data suggest that obesity correlates with airway hyper-reactivity. However, the incidence of bronchospasm during bariatric surgery in obese patients has not been well studied. METHODS: This was a prospective observational study comparing 50 obese versus 50 non obese patients undergoing elective laparoscopic surgery over a 2 year period. Bronchospasm was detected clinically by auscultation and was confirmed by measuring peak airway pressure during mechanical ventilation. Blood gases were measured at predetermined time intervals intraoperatively. Categorical variables were analyzed using Fisher's exact test, while numerical variables within and between groups were compared using repeated measures general linear model. RESULTS: The incidence of bronchospasm was significantly higher in obese compared to non obese patients (P = 0.027). Peak airway pressures and blood gases differed significantly when comparing non obese patients versus obese patients without bronchospasm versus obese patients with bronchospasm. Hypoventilation resulting in gradual increase of arterial PaCO2 was noted in all groups during surgery. CONCLUSION: The incidence of bronchospasm is higher in obese patients compared to non obese patients undergoing elective laparoscopic surgery. Airway pressures and blood gas values in obese patients are somewhere between values in non obese patients and values in patients with bronchospasm, thereby implying that obesity is associated with a state where bronchial smooth muscles are not fully relaxed. Consideration of increased airway reactivity in obese patients undergoing laparoscopic surgery is important for improved patient care and uneventful anesthetic course.

Depth of Anesthesia as a Risk Factor for Perioperative Morbidity.

Introduction. The prognostic value of age, physical status, and duration of surgery on perioperative course has been extensively studied. However, the impact of deep hypnotic time (time when Bispectral Index values are less than 40) has not been well evaluated. Methods. We designed an observational study to clarify the relative influence of deep hypnotic time (DHT) on outcome. Eligible participants were mentally stable patients over 18 years old scheduled for elective major abdominal surgery. In total, 248 patients enrolled. Data were analyzed using Fisher's exact test and multiple logistic regression. Results. Five variables (DHT, hypotension, age, comorbidity, and duration of surgery) showed statistically significant association with complications, when examined independently. However, when all variables were examined together in a multiple logistic regression model, age and comorbidity were no longer associated with outcome. DHT, hypotension, and duration of surgery were significant predictors of "complications," and "hypotension" was a significant predictor of prolonged hospital stay (P < 0.001). Conclusion. Deep hypnotic time emerged as a new factor associated with outcome, and its impact compared to other factors such as age, surgery duration, hypotension, and comorbidity is redefined. Monitoring and managing depth of anesthesia during surgery are important and should be part of careful operation planning.

Epithelial-myoepithelial carcinoma of the trachea-a rare entity case report.

Epithelial-myoepithelial tumors of the lung are rare neoplasms whose biological behavior and clinical course still remain to be defined. Epithelial-myoepithelial carcinoma (EMCa) is a low-grade malignant tumour. According to literature, most commonly occurs in salivary glands, particularly in parotic gland, but it can also occur in unusual locations such as breast, lachrymal gland, nose, paranasal sinus, lung, bronchus and, as in our case, trachea. There are no many documented case reports of a primary myoepithelial carcinoma in the trachea. We report a case of a 34-year-old man diagnosed with this unusual location of an epithelial-myoepithelial tumor. The tumour was removed by segmental tracheal resection and end-to-end anastomosis.

Cerebral oximetry in cardiac anesthesia.

Cerebral oximetry based on near-infrared spectroscopy (NIRS) is increasingly used during the perioperative period of cardiovascular operations. It is a noninvasive technology that can monitor the regional oxygen saturation of the frontal cortex. Current literature indicates that it can stratify patients preoperatively according their risk. Intraoperatively, it provides continuous information about brain oxygenation and allows the use of brain as sentinel organ indexing overall organ perfusion and injury. This review focuses on the clinical validity and applicability of this monitor for cardiac surgical patients.

Regional anesthesia for laparoscopic surgery: a narrative review.

Laparoscopic surgery has advanced remarkably in recent years, resulting in reduced morbidity and shorter hospital stay compared with open surgery. Despite challenges from the expanding array of laparoscopic procedures performed with the use of pneumoperitoneum on increasingly sick patients, anesthesia has remained largely unchanged. At present, most laparoscopic operations are usually performed under general anesthesia, except for patients deemed "too sick" for general anesthesia. Recently, however, several large, retrospective studies questioned the widely held belief that general anesthesia is the best anesthetic method for laparoscopic surgery and suggested that regional anesthesia could also be a reasonable choice in certain settings. This narrative review is an attempt to critically summarize current evidence on regional anesthesia for laparoscopic surgery. Because most available data come from large, retrospective studies, large, rigorous, prospective clinical trials comparing regional vs. general anesthesia are needed to evaluate the true value of regional anesthesia in laparoscopic surgery.

Peripheral nerve blockade as an exclusive approach to obturator nerve block in anterior cruciate ligament reconstructive surgery.

BACKGROUND: Obturator nerve block plays an additive role on the quality of analgesia for knee surgery. Since the use of dual guidance increases the success rate of nerve blocks, we investigated the feasibility of performing anterior cruciate ligament reconstruction under dual-guided blockade of obturator with femoral and sciatic nerves. Furthermore, we propose a novel method for the assessment of obturator nerve block. METHODS: Fifty-seven patients undergoing anterior cruciate ligament repair were studied. Neurostimulating needles were guided out-of-plane by ultrasound. To induce the obturator nerve block, 10 ml of ropivacaine 0.5% were injected after eliciting contractions of adductor longus, brevis and magnus followed by block assessment for 30 minutes by examining the patient lift and left down the leg. RESULTS: The sonographic recognition of obturator nerve was easy and quick in all cases. Time for applying the block was 119.9 ± 79.2 sec. Assessing this block with lifting-leaving down the leg gave satisfactory results in 24.0 ± 5.07 min. After performing femoral-sciatic blocks, the inflation of tourniquet resulted in VAS score of > 0 in 2/57 patients and operation in 12/57. Total dose of fentanyl was 120.1 ± 64.6 µg and of midazolam 1.86 ± 0.8 mg. In 6 patients propofol was administered for sedation and 1 of them required ventilation with laryngeal mask airway, converting the anesthesia technique to general anesthesia. CONCLUSIONS: Our data suggest that anterior cruciate ligament reconstruction can be performed under obturator-femoral-sciatic blocks. Identification of obturator nerve with ultrasound is easy and the block can be assessed by observing how the patient lifts and leaves down the leg.

Supraventricular arrhythmias after thoracotomy: is there a role for autonomic imbalance?

Supraventricular arrhythmias are common rhythm disturbances following pulmonary surgery. The overall incidence varies between 3.2% and 30% in the literature, while atrial fibrillation is the most common form. These arrhythmias usually have an uneventful clinical course and revert to normal sinus rhythm, usually before patent's discharge from hospital. Their importance lies in the immediate hemodynamic consequences, the potential for systemic embolization and the consequent long-term need for prophylactic drug administration, and the increased cost of hospitalization. Their incidence is probably related to the magnitude of the performed operative procedure, occurring more frequently after pneumonectomy than after lobectomy. Investigators believe that surgical factors (irritation of the atria per se or on the ground of chronic inflammation of aged atria), direct injury to the anatomic structure of the autonomic nervous system in the thoracic cavity, and postthoracotomy pain may contribute independently or in association with each other to the development of these arrhythmias. This review discusses currently available information about the potential mechanisms and risk factors for these rhythm disturbances. The discussion is in particular focused on the role of postoperative pain and its relation to the autonomic imbalance, in an attempt to avoid or minimize discomfort with proper analgesia utilization.

Monitoring of brain oxygen saturation (INVOS) in a protocol to direct blood transfusions during cardiac surgery: a prospective randomized clinical trial.

BACKGROUND: Blood transfusions are common in cardiac surgery, but have been associated with increased morbidity and long-term mortality. Efforts to reduce blood product use during cardiac surgery include fluid restriction to minimize hemodilution, and protocols to guide transfusion decisions. INVOS is a modality that monitors brain tissue oxygen saturation, and could be useful in guiding decisions to transfuse. However, the role of INVOS (brain tissue oxygen saturation) as part of an algorithm to direct blood transfusions during cardiac surgery has not been evaluated. This study was conducted to investigate the value of INVOS as part of a protocol for blood transfusions during cardiac surgery. METHODS: Prospective, randomized, blinded clinical trial, on 150 (75 per group) elective cardiac surgery patients. The study was approved by the Institution Ethics committee and all patients gave written informed consent. Data were initially analyzed based on "intention to treat", but subsequently were also analyzed "per protocol". RESULTS: When protocol was strictly followed ("per protocol analysis"), compared to the control group, significantly fewer patients monitored with INVOS received any blood transfusions (46 of 70 patients in INVOS group vs. 55 of 67 patients in the control group, p = 0.029). Similarly, patients monitored with INVOS received significantly fewer units of red blood cell transfusions intraoperatively (0.20 ± 0.50 vs. 0.52 ± 0.88, p = 0.008) and overall during hospital stay (1.31 ± 1.20 vs. 1.82 ± 1.46, p = 0.024). When data from all patients (including patient with protocol violation) were analyzed together ("intention to treat analysis"), the observed reduction of blood transfusions in the INVOS group was still significant (51 of 75 patients transfused in the INVOS group vs. 63 of 75 patients transfused in the control group, p = 0.021), but the overall number of units transfused per patient did not differ significantly between the groups (1.55 ± 1.97 vs. 1.84 ± 1.41, p = 0.288). CONCLUSIONS: Our data suggest that INVOS could be a useful tool as part of an algorithm to guide decisions for blood transfusion in cardiac surgery. Additional data from rigorous, well designed studies are needed to further evaluate the role of INVOS in guiding blood transfusions in cardiac surgery, and circumvent the limitations of this study.

Effect of interscalene brachial plexus block on heart rate variability.

BACKGROUND: Interscalene brachial plexus block (ISB) may be followed by cardiovascular instability. Until date, there is no clear picture available about the underlying mechanisms of ISB. In this study, we aimed to determine the changes in heart rate variability (HRV) parameters after ISB and the differences between right- and left-sided ISBs. METHODS: We prospectively studied 24 patients operated for shoulder surgery in sitting position and divided them into two respective groups: R (right-sided block = 14 pts) and L (left-sided block = 10 pts). HRV data were taken before and 30 min after the block. Ropivacaine without ephedrine was used for the ISB through an insulated block needle connected to a nerve stimulator. Statistical analysis implemented chi-square, Student's and t-paired tests. Skewed distributions were analyzed after logarithmic transformation. RESULTS: All the studied patients had successful blocks. Horner's syndrome signs were observed in 33.3% of the patients (R = 5/14, L = 3/10; [P = 0.769]). There were no significant differences in pre-block HRV between the groups. The application of ISB had differential effect on HRV variables: R-blocks increased QRS and QTc durations and InPNN50, while a statistical decrease was seen in InLF. L-blocks did not show any significant changes. These changes indicate a reduced sympathetic and an increased parasympathetic influence on the heart's autonomic flow after R-block. CONCLUSIONS: Based on the obtained results we conclude that ISB, possibly through extension of block to the ipsilateral stellate ganglion, alters the autonomic outflow to the central circulatory system in a way depending on the block's side.

Impact of intraoperative hypotension on hospital stay in major abdominal surgery.

PURPOSE: Although the relationship between preoperative risk factors and outcomes has been extensively studied, the effect of intraoperative hemodynamic changes in a patient's postoperative course has been less well defined. METHODS: We designed a prospective observational study to assess the impact of several variables, and especially hypotension, on postoperative outcome. Patients considered eligible for the study, all more than 18 years old, were mentally stable patients scheduled for major abdominal surgery with an expected duration of more than 2 h. Total hypotension time (THT), with other variables that possibly influence the outcome, was analyzed using multivariate logistic regression analysis in 100 consecutive patients. RESULTS: Total hypotension time was isolated as a factor significantly associated with morbidity [odds ratio, 5.1 (1.95-13.35)] and significantly prolonged hospital stay [odds ratio, 4.56 (1.85-10.96)]. Patients who had prolonged THT presented more complications (50 vs. 30), especially of the cardiovascular, pulmonary, and gastrointestinal systems. These complications led to delayed hospital discharge in a significant number of patients (36 with THT vs. 17 others). Finally, duration of surgery was associated with postoperative complications [odds ratio, 3.1 (1.2-8.0)]. CONCLUSION: Persistent hypotension during elective major abdominal surgery is a significant risk factor for postoperative complications and may prolong hospitalization and affect patient outcomes. Anesthetic management for the avoidance of hypotension, as much as possible, during major abdominal surgery may positively affect outcomes.

Management of intraoperative fluid balance and blood conservation techniques in adult cardiac surgery.

Blood transfusions are associated with adverse physiologic effects and increased cost, and therefore reduction of blood product use during surgery is a desirable goal for all patients. Cardiac surgery is a major consumer of donor blood products, especially when cardiopulmonary bypass (CPB) is used, because hematocrit drops precipitously during CPB due to blood loss and blood cell dilution. Advanced age, low preoperative red blood cell volume (preoperative anemia or small body size), preoperative antiplatelet or antithrombotic drugs, complex or re-operative procedures or emergency operations, and patient comorbidities were identified as important transfusion risk indicators in a report recently published by the Society of Cardiovascular Anesthesiologists. This report also identified several pre- and intraoperative interventions that may help reduce blood transfusions, including off-pump procedures, preoperative autologous blood donation, normovolemic hemodilution, and routine cell saver use.A multimodal approach to blood conservation, with high-risk patients receiving all available interventions, may help preserve vital organ perfusion and reduce blood product utilization. In addition, because positive intravenous fluid balance is a significant factor affecting hemodilution during cardiac surgery, especially when CPB is used, strategies aimed at limiting intraoperative fluid balance positiveness may also lead to reduced blood product utilization.This review discusses currently available techniques that can be used intraoperatively in an attempt to avoid or minimize fluid balance positiveness, to preserve the patient's own red blood cells, and to decrease blood product utilization during cardiac surgery.

Thoracic epidural analgesia with levobupivacaine for 6 postoperative days attenuates sympathetic activation after thoracic surgery.

OBJECTIVE: To investigate the impact of 2 postoperative analgesic regimens on heart rate variability in patients who underwent thoracotomy. DESIGN: A prospective, randomized trial. SETTING: A single-institutional study in a university hospital. PARTICIPANTS: Fifty patients who underwent thoracotomy under combined general anesthesia and thoracic epidural analgesia divided by a number generator into 2 equal groups (A and B). INTERVENTIONS: In group A, postoperative analgesia consisted of thoracic epidural analgesia with levobupivacaine for 6 postoperative days. In group B, on the 3rd postoperative day this regimen was changed to patient-controlled intravenous morphine. Heart rate variability recordings were performed on the day before surgery, after the epidural, after operation, and on every postoperative day. Statistical analysis used chi-square and Student t tests (Bonferroni correction). MEASUREMENTS AND MAIN RESULTS: In both groups, the low-frequency component of the analyzed recordings declined after epidural and after surgery. In group A, the low-frequency component was significantly lower compared with baseline from the 2nd postoperative day onward, whereas in group B it was significantly higher compared with A on the 4th and 6th postoperative days. In both groups, the changes in high frequency were statistically insignificant. Intergroup comparisons of the low-/high-frequency ratio showed statistical difference on the last day of observation. There was no difference between the groups in hemodynamic variables and visual analog scale/10 scores. CONCLUSIONS: Postoperatively decreased cardiac sympathetic outflow continues with epidural analgesia, whereas it is abolished by the change to intravenous patient-controlled morphine.

Intra-operative intravenous fluid restriction reduces perioperative red blood cell transfusion in elective cardiac surgery, especially in transfusion-prone patients: a prospective, randomized controlled trial.

BACKGROUND: Cardiac surgery is a major consumer of blood products, and hemodilution increases transfusion requirements during cardiac surgery under CPB. As intraoperative parenteral fluids contribute to hemodilution, we evaluated the hypothesis that intraoperative fluid restriction reduces packed red-cell (PRC) use, especially in transfusion-prone adults undergoing elective cardiac surgery. METHODS: 192 patients were randomly assigned to restrictive (group A, 100 pts), or liberal (group B, 92 pts) intraoperative intravenous fluid administration. All operations were conducted by the same team (same surgeon and perfusionist). After anesthesia induction, intravenous fluids were turned off in Group A (fluid restriction) patients, who only received fluids if directed by protocol. In contrast, intravenous fluid administration was unrestricted in group B. Transfusion decisions were made by the attending anesthesiologist, based on identical transfusion guidelines for both groups. RESULTS: 137 of 192 patients received 289 PRC units in total. Age, sex, weight, height, BMI, BSA, LVEF, CPB duration and surgery duration did not differ between groups. Fluid balance was less positive in Group A. Fewer group A patients (62/100) required transfusion compared to group B (75/92, p < 0.04). Group A patients received fewer PRC units (113) compared to group B (176; p < 0.0001). Intraoperatively, the number of transfused units and transfused patients was lower in group A (31 u in 19 pts vs. 111 u in 62 pts; p < 0.001). Transfusions in ICU did not differ significantly between groups. Transfused patients had higher age, lower weight, height, BSA and preoperative hematocrit, but no difference in BMI or discharge hematocrit. Group B (p < 0.005) and female gender (p < 0.001) were associated with higher transfusion probability. Logistic regression identified group and preoperative hematocrit as significant predictors of transfusion. CONCLUSIONS: Our data suggest that fluid restriction reduces intraoperative PRC transfusions without significantly increasing postoperative transfusions in cardiac surgery; this effect is more pronounced in transfusion-prone patients. TRIAL REGISTRATION: NCT00600704, at the United States National Institutes of Health.

Endobrochial blockade through a tracheostomy tube for lung isolation.

We present an alternative technique for one-lung ventilation as safe way of treating patients with tracheostomy using a fiberoptic bronchoscope and a Fogarty catheter.