A year in review in Minerva Anestesiologica 2013.

BACKGROUND: We organized a training program for oral fiber optic intubation (FOI) under conscious sedation. The efficacy of the program was evaluated by comparing the performances of experts and novices. METHODS: The training procedure was divided into two sessions: a theoretical session on difficult airways, the fiber optic bronchoscope (FOB), remifentanil, topical anesthesia and patient interactions; and a session involving simulations of the FOI technique on dummies. For in vivo FOI, we enrolled patients requiring orotracheal intubation for elective surgery. Electrocardiograms, mean arterial pressure was railroaded over the fiberscope, and tracheal intubati6 and 7) FOIs, respectively, joined the study. To reach ±23 bpm, P=0.02), and RR was decreased (from 16±3 to 12±4 bpm, P<0.05). No differences were recorded between the experts and less-experienced anesthesiologists. The average duration of FOI was 3.3±2.0 min for experts and 4.2±2.4 min for novices (P=0.03). Procedures were successful in both groups, with patients in each group being equally satisfied with the procedures. CONCLUSION: This study highlights the importance of a structured FOI training program, demonstrating that it is possible to learn to perform FOI proficiently by practicing on dummies.

New drugs for epidural analgesia.

In recent years there has been a wide use of the epidural technique not only during surgery to provide anesthesia and analgesia, but also for obstetric and trauma as well as acute, chronic and cancer pain states. Nowadays there is an increase in the number of the epidural drugs. Local anesthetics and opioids are still the pharmacological agents more widely used epidurally, nevertheless other drugs from different pharmacological classes are administered as adjuvant to local anesthetics and opioids or are in various early stages of investigation. Regarding to local anesthetics, the most recent literature focuses on the new enantiomers, ropivacaine and levobupivacaine, the efficacy of which is similar to that of bupivacaine with a reduced risk of cardiotoxicity. About opioids, the other class of drugs mainly used, the debate, in the last years, concerned the physicochemical properties of morphine and of the more recent lipophilic agents, fentanyl and sufentanil, in order to explain the main differences in efficacy and safety. Other categories of agents have been investigated for epidural administration, such as alpha(2)-adrenergic agonists clonidine and dexmedetomidine. They are being used increasingly as adjuvants to local anesthetics and opioids. Ketamine and neostigmine, the more recent studied drugs for epidural use, are still under investigation and are not part of routine clinical practice.

Analgesia in thoracic surgery: review.

Post-thoracotomy pain is one of the most severe types of postoperative pain. It can last up to 2 months and can become chronic in 30% of patients. Pain relief after thoracic surgery is of particular significance, not only for ethical considerations but also for reduction of postoperative pulmonary and cardiac complications. Because of the difficulty in pain control, many approaches have been suggested, but a multimodal therapeutic strategy that provides a central or peripheral block associated with nonsteroidal anti-inflammatory (NSAID) and adjuvant drugs is now the cornerstone of treatment, offering the possibility of reducing opioid requirements and side effects. Thoracic epidural analgesia with local anesthetics and opioids is regarded as the gold standard treatment for post-thoracotomy pain management because it results in early extubation, better ventilatory mechanisms and gas exchange, decreased incidence of atelectasis, pneumonia and chronic postoperative pain. When epidural analgesia is contraindicated or cannot be performed, other regional techniques of analgesia can be used. An alternative method of providing adequate pain relief is a thoracic paravertebral block: continuous paravertebral infusion of local anesthetic via a catheter placed percutaneously or under direct vision during thoracotomy. This is effective in controlling postoperative pain and in preserving pulmonary function. Other techniques, such as intercostal and interpleural blocks, are rarely utilized, whereas a single shot of intrathecal injection of a hydrophilic opioid, such as morphine, appears to be effective. Cryoanalgesia, which is successful in the immediate postoperative period, has been abandoned for its brief duration and increased incidence of chronic pain.

Ropivacaine vs. levobupivacaine combined with sufentanil for epidural analgesia after lung surgery.

BACKGROUND AND OBJECTIVES: There are no clinical studies that compare epidural infusion of ropivacaine and levobupivacaine in patients undergoing lung surgery. The aim of this prospective, randomized double-blind study was to evaluate the efficacy and safety of two commercially available solutions of ropivacaine (0.2% w/v) and levobupivacaine (0.125% w/v) when administered by continuous epidural infusion together with sufentanil in patients undergoing lung surgery. METHODS: After obtaining informed consent, 54 patients, ASA physical status I-III undergoing lung resection, were enrolled. Patients were randomly assigned to two groups in which analgesia was performed by continuous thoracic epidural infusion of ropivacaine 0.2% w/v (Group R) or levobupivacaine 0.125% w/v (Group L) with or without sufentanil 1 microg mL(-1). After a test and a loading dose of each drug for the respective group, continuous epidural infusion, set at 5 mL h(-1), began. General anaesthesia was standardized. In the recovery room, patients were provided with intravenous morphine patient-controlled analgesia. Visual analogue scale at rest and when coughing, rescue patient-controlled analgesia morphine amount, haemodynamics, sensory and motor block, sedation, nausea and vomiting, patient satisfaction score, were evaluated within 48 h. RESULTS: The two groups were similar regarding patient characteristics, quality of analgesia, level of sensory block, morphine consumption and satisfaction score. Postoperative haemodynamic profile was stable in all the patients. Minor side-effects occurred with a similar incidence. Motor block was not seen. CONCLUSIONS: Equivalent volumes of ropivacaine (0.2% w/v) and levobupivacaine (0.125% w/v) provided similar static and dynamic analgesia with similar incidence of minor side-effects after thoracotomy.

Epidural infusion of levobupivacaine and sufentanil following thoracotomy.

A prospective, randomised, double-blind study was conducted to compare the efficacy of two doses of levobupivacaine combined with sufentanil for continuous epidural infusion following thoractomy. A total of 72 patients undergoing lobectomy or pneumonectomy were enrolled. An epidural catheter was inserted between the levels of T4 and T6 before induction of anaesthesia and a loading dose of levobupivacaine and sufentanil was administered. At the end of surgery an epidural infusion was commenced at 5 mlxh(-1) and continued for 48 h. Patients were randomly allocated to receive either levobupivacaine 0.125% (group A) or 0.0625% (group B) and all patients also received sufentanil (1 microgxml(-1)). Visual analogue pain scores after coughing (VASi) were always higher in group B (p < 0.05); VAS pain scores at rest were higher for the first 4 h and at 16 and 28 h in group B (p < 0.05). Total morphine consumption and requests number was lower in group A (p < 0.05). Better pain relief was achieved using epidural 0.125% levobupivacaine.

Use of levobupivacaine for the treatment of postoperative pain after thoracotomies.

Continuous thoracic epidural analgesia with an opiod-local anaesthetic mixture is the most appropriate strategy to control postoperative pain in thoracic surgery. Levobupivacaine, the pure S(-) enantiomer of racemic bupivacaine, has less cardiotoxic and neurotoxic potential but similar anaesthetic properties of its native agent. There are no studies in thoracic surgery that had established the minimal efficient concentration of this anaesthetic when used with an epidural opioid. The advantages of administering opioids in addition to local anaesthetics in the epidural space are the possibility to decrease dose and consequently side-effects of each drug and to exploit the documented synergy between these different categories of drugs in producing segmental epidural analgesia. In our departmental study (unpublished data), 2 different concentration of levobupivacaine (Group A: 0.125% and Group B: 0.0625%) combined with sufentanil (1 mg/mL) were administered in continuous epidural post-thoracotomy infusion to investigate quality of analgesia, motor block and side-effects. An intravenous PCA system has been used in the postoperative period to evaluate rescue morphine consumption. Preliminary results showed that patients of each group reported similar VAS at rest although a better pain control during cough resulted in group A. Patients receiving levobupivacaine at 0.125% presented low incidence of nausea, vomiting and pruritus probably because of the smaller amount of rescue morphine administered. At the concentration of 0.125% epidural levobupivacaine in combination with sufentanil allowed to obtain a good pain control with no adverse effects and motor block at all.

Epidural analgesia in abdominal surgery: 0.2% ropivacaine with sufentanil.

AIM: Combining an opioid with peridural local analgesia is an excellent technique to control post-operative pain. Sufentanil is a widely used opioid agent, but its optimal dosage has not yet been defined. In this study we wanted to determine the best dose of epidural sufentanil in major surgery. METHODS: Before the operation, 45 major abdominal surgery patients received blended anesthesia through an epidural chest catheter. The patients were randomized into 3 groups of 15 subjects according to different sufentanil doses [0.2% ropivacaine combined with sufentanil at a dose of 0.5 microg/ml(-1), 0.75 microg/ml(-1), or 1 microg/ml(-1) (groups A, B and C, respectively)] administered through an epidural chest catheter connected to an elastometric pump (5 ml/h) for the first 36 postoperative hours. The level of postoperative analgesia in motion and at rest was measured using an analog visual scale (VAS-R, VAS-I). RESULTS: Analgesia was best in group A, and similar in groups B and C; 2 cases of pruritus were noted in group C. The VAS-I scores were <3 across all 3 patient groups. CONCLUSION: Epidural analgesia is an efficacious and reliable technique. The combination of 0.2% ropivacaine and 0.75 microg/ml(-1) sufentanil was found to be the optimum choice between analgesic efficacy and minor side effects, which correlated with the higher dose of sufentanil given to group C.

[Anesthesia and concomitant pathologies: anesthesia in the elderly patient]. / Anestesia e patologie concomitanti: l'anestesia nell'anziano.

With the increase in the average age of the population, more and more older persons undergo surgery. Major surgery, cardiovascular, orthopaedic and abdominal interventions expose the elderly patient to a significant risk for postoperative morbidity and mortality. This is not only related to the advanced age of these subjects, which is a recognized independent risk factor, but also to the aging process itself and to the greater prevalence of heart and lung diseases affecting this population segment. An important role is also played by the so-called physiologic modification found in subjects without recognized illnesses. Reduced organ function reserve requires accurate preoperative assessment that takes into account cardiovascular reserve and physiologic and pathologic alterations in the respiratory system that may predispose the patient to hypoxemia and favour the development of postoperative infection. Moreover, alterations in pharmacokinetics and pharmacodynamics require individualized drug dosing. Particular attention should also be directed at the prevention of postoperative cognitive disorders that favour the development of complications and negatively affect postoperative recovery of body function.

Auditory evoked potentials.

Auditory evoked potentials (AEPs) are an electrical manifestation of the brain response to an auditory stimulus. Mid-latency auditory evoked potentials (MLAEPs) and the coherent frequency of the AEP are the most promising for monitoring depth of anaesthesia. MLAEPs show graded changes with increasing anaesthetic concentration over the clinical concentration range. The latencies of Pa and Nb lengthen and their amplitudes reduce. These changes in features of waveform are similar with both inhaled and intravenous anaesthetics. Changes in latency of Pa and Nb waves are highly correlated to a transition from awake to loss of consciousness. MLAEPs recording may also provide information about cerebral processing of the auditory input, probably because it reflects activity in the temporal lobe/primary cortex, sites involved in sounds elaboration and in a complex mechanism of implicit (non declarative) memory processing. The coherent frequency has found to be disrupted by the anaesthetics as well as to be implicated in attentional mechanism. These results support the concept that the AEPs reflects the balance between the arousal effects of surgical stimulation and the depressant effects of anaesthetics. However, AEPs aren't a perfect measure of anaesthesia depth. They can't predict patients movements during surgery and the signal may be affected by muscle artefacts, diathermy and other electrical operating theatre interferences. In conclusion, once reliability of the AEPs recording became proved and the signal acquisition improved it is likely to became a routine feature of clinical anaesthetic practice.

Interleukin-6 release in the hepatic blood outflow during normothermic liver ischaemia in humans.

BACKGROUND: Liver surgery techniques have consistently improved and normothermic ischaemia of the liver is considered to be a safe procedure to reduce intraoperative haemorrhage. Hepatic failure, however, remains a significant complication. In liver ischaemia-reperfusion injury, cytokines play a key proinflammatory role. Cytokines may be part of the intercellular signalling that leads to recovery or to failure after major surgery. Moreover, they could be potential predictors of the outcome. Modulation of the pattern of cytokine response in the early postsurgery period could represent a new approach to minimise the impact of these procedures. AIMS: The aim of our study was to analyse the cytokine pattern in the hepatic blood outflow in patients undergoing surgical intervention of partial liver resection with clamping of the hepatic pedicle and liver ischaemia, and to correlate the cytokine behaviour with clinical parameters. PATIENTS: We studied eight patients (mean age 55 years) who underwent surgical intervention of liver resection during vascular exclusion of the hepatic pedicle. Patients were monitored for haemodynamic and haematological parameters during the pre-, infra- and postoperative period. METHODS: IL-I alpha, IL-6, TNF-alpha and IFN-gamma were assayed from peripheral and central vein blood at different times. Blood samples for cytokine assays were also drawn from the supra-hepatic veins after clamping of the porta hepatis. RESULTS: We found a significant increase of the IL-6 levels in the supra-hepatic samples during liver ischaemia, while the trend with IL-1alpha was less clear; IFN-gamma and TNF-alpha were undetectable with the methods used. IL-6 levels appeared to correlate positively with bilirubin and gamma-GT levels and negatively with the degree of acidosis. CONCLUSIONS: Our study confirms that during surgical ischaemic stress there is an increase of IL-6 serum levels more relevant in supra-hepatic vein blood. Cytokines could contribute to modulate the inflammatory response to liver ischaemia.

[Gas embolism during hysteroscopy. A case report]. / Embolia gassosa durante isteroscopia.

A case of gas embolism during hysteroscopy in a young woman suffering from sterility is reported. Although this surgical procedure is considered safe, however, when complications do occur, they can be severe and rapidly fatal. The importance of an accurate intraoperative monitoring for a rapid diagnosis and treatment remarkably improve the clinical picture of the patient.

Liver resections with or without pedicle clamping.

BACKGROUND: Decreasing operative bleeding during liver resection, and thus extent of transfusions, has become a main criterion to evaluate operative results of hepatectomies. Hepatic pedicle clamping (HPC) is widely used for this purpose. The aim of the study was to evaluate safety, efficacy, technique, and contraindications of HPC during liver resections, comparing results of resections performed with or without HPC. METHODS: Data from 245 liver resections were analyzed. In all, 125 resections were performed with HPC (group A), continuous in 100 cases and intermittent in 25 cases. The average duration of ischemia in group A was 39 +/- 20 minutes (range 7 to 107). In 20 cases (16%) ischemia was prolonged for 60 minutes or more. A total of 120 resections were performed without HPC (group B). Major resections were 53.6% in group A (67 cases) and 38.3% in group B (46 cases). Cirrhosis was present in 36 cases, 19 in group A and 17 in group B. RESULTS: Operative mortality was nil. Postoperative mortality was 2.9%, morbidity 22.4%. Percentage of transfused cases (34.4% versus 60.0%; P <0.001) and number of blood units per transfused case (2 +/- 1 versus 4 +/- 3; P <0.001) were lower in group A versus group B. Similar figures were found by considering only major resections. Postoperative blood chemistries did not show important differences between the two groups, and postoperative alterations were related more to extent and complexity of the operation than to length of HPC. CONCLUSIONS: HPC during liver resection is a safe and effective technique. This is demonstrated in a context where HPC is used continuously in most cases, intermittently in cases with impaired liver function and for more prolonged ischemia, and avoided in cases with limited bleeding, jaundice, and simultaneous bowel anastomoses.

Haemodynamic and metabolic changes during major liver resection with use of hepatic total vascular exclusion.

We evaluated haemodynamic changes during major liver resection that involved total hepatic vascular exclusion (HVE) carried out through clamping hepatic pedicle and inferior caval vein upper and above the liver. Fourteen patients, undergoing different procedures of major liver resection, were enrolled in this study which used complete cardiovascular monitoring. Haemodynamic parameters were measured and calculated at five different times during the operation. Changes such as reduction in cardiac output and increase in systemic vascular resistance, though significant, were well tolerated in all patients, allowing the execution of major liver surgery. HVE offers a significant reduction in haemorrhagic and air embolus risk, but it requires the use of complete haemodynamic monitoring to evaluate tolerance to clamping and correction of unavoidable cardiovascular changes.

Changes in cerebral hemodynamics during laparoscopic cholecystectomy.

Laparoscopic surgery requires a series of procedures, including intraperitoneal CO2 insufflation, which can cause cardiovascular and hemogasanalytic modifications, potentially able to impair cerebral perfusion. The aim of this study was to evaluate changes in cerebral blood flow velocity during laparoscopic cholecystectomy. Eighteen patients undergoing laparoscopic cholecystectomy were studied. Middle cerebral artery blood flow velocity was monitored using transcranial Doppler ultrasonography. Electrical bioimpedance was employed to measure cardiac output, stroke volume and to calculate derived parameters. End-tidal CO2, mean arterial blood pressure, end expiratory anesthetic concentration and O2 saturation were monitored non-invasively. Cerebral artery blood flow velocity increased significantly after CO2 insufflation (p < 0.05) and remained stable. The highest values were reached after CO2 desufflation. A significant reduction in stroke volume and cardiac output (p < 0.05) associated with increased vascular systemic resistances (p < 0.001) was observed soon after CO2 insufflation. The decrease in cardiac output and the increase in vascular systemic resistances remained significant throughout abdominal insufflation. Heart rate and mean arterial pressure remained substantially unchanged with the exception of a significant decrease (p < 0.001) before CO2 insufflation. There was no significant change in end-tidal CO2 during abdominal insufflation. These findings suggest that the cerebrovascular system can undergo adaptive changes during all phases of laparoscopic surgery. However, the extent of cardio- and cerebrovascular variation indicates the need for careful preliminary evaluation of cerebral hemodynamics in patients with vascular disorders before laparoscopic surgery.

[Target controlled infusion (TCI): applications of the "TCI visual" program in anesthesia and sedation with propofol]. / Target controlled infusion (TCI): applicazione del programma "visual TCI" all'anestesia ed alla sedazione col propofol.

BACKGROUND: Systems for Target Controlled Infusion accepting not only patient' data, like Diprifusor, but also a pharmacokinetic model have not been available in Italy in the last years. Therefore a program which controls a Pilot Anesthesia Vial pump and accepts any pharmacokinetic model was developed and applied to propofol infusion for anaesthesia and sedation. METHODS: Two versions of the Visual TCI program have been developed. The first, at intervals, supplies the anaesthetist with the values for the pump; the second directly interacts with the pump. The program also supplies the anaesthetist with the current amount of drug in each compartment and with the estimated awakening time. DESIGN: preliminary prospective study. SETTING: operatory theatre and Intensive Care Unit in a University Hospital. PATIENTS: 6 patients undergoing total intravenous anaesthesia with propofol and fentanyl for abdominal surgery; 6 patients undergoing sedation with propofol in an Intensive Care Unit (the first 4-hour period was taken into account). INTERVENTIONS: propofol infusion was regulated by the Visual TCI program. The first version was employed in three patients of each group and the second one in the others. Hypo- and hypertensive episodes (systolic pressure less than 80 mmHg or higher than basal value plus 25%) were recorded during anaesthesia and sedation. Propofol concentration was measured in plasma three times at defined intervals and per cent differences between measured and computer-calculated values (Predictive error, PE) were calculated. RESULTS: No hypo- or hypertensive episodes were recorded. PE was 27.4 +/- 17.9%. CONCLUSIONS: The program was easily employed, caused no inconvenience, and its use was associated with a remarkable cardiovascular stability. PE distribution was acceptable on the ground of the criteria reported in the literature. The program can be applied to drugs other than propofol, with both two and three compartment pharmacokinetic models and the anaesthetist can choose the most suitable model for the patient.

Assessment of risk factors for pancreatic resection for cancer.

A series of 101 consecutive patients undergoing pancreatic resection for cancer was retrospectively analyzed to define factors that may affect the immediate postoperative outcome. Overall morbidity and mortality were 28.7% and 10.9%, respectively, although these figures were greatly reduced during the last years; the complication rate dropped from 55.6% (1981-1987) to 20.0% (1993-1995) and the mortality from 16.7% to 6.7%. At univariate statistical analysis the patient characteristics (sex, age, American Society of Anesthesiologists [ASA] class, nutritional status, jaundice), tumor characteristics (site, size, TNM stage, and grading), and type of surgery were found not to affect postoperative morbidity and mortality. In contrast, a significantly lower rate of complications was observed in patients not undergoing gastric resection, in those who received 3 units or less of blood intraoperatively, and in subjects operated more recently (after 1990). At multivariate analysis the period when the operation was performed was the only independent variable that affected the immediate postoperative outcome. Among the examined factors, only the experience acquired over time regarding the intra- and perioperative treatment of these patients seems able to lower the rate of postoperative complications.

Hepatic resections in normothermic ischemia.

BACKGROUND: Reduction of operative blood transfusions is a primary goal in resective surgery of the liver. Temporary vascular inflow occlusion is an effective method to decrease hemorrhage during hepatic resection. This study was performed to assess the impact of normothermic ischemia on intraoperative bleeding and outcome after hepatic resection. METHODS: Sixty-one hepatic resections were performed by using pedicle clamping alone or associated with total vascular exclusion of the liver. The mean duration of normothermic ischemia was 40 +/- 18 minutes (range, 7 to 98 minutes). Major resections were performed in 32 cases (52.5%). RESULTS: Operative mortality was nil. Major complications occurred in 11.5% of cases. Twenty-five patients (41%) received intraoperative blood transfusions; mean +/- SD of transfused blood units was 2.4 +/- 1.3. Twelve major resections (37.5%) did not require any transfusion. Postoperative changes in liver function test results were moderate and transient. CONCLUSIONS: The results of this study confirm the benefit of vascular occlusion techniques in reducing intraoperative bleeding and postoperative complications. The routine use of these techniques during hepatic resections, if applied properly and with the necessary precautions, is not associated with severe adverse effects on liver function.

[Anesthesia in the elderly patient. Our experience]. / L'anestesia nel paziente anziano. Nostra esperienza.

A study has been carried out in 435 patients over 80 years old underwent elective or emergency general surgical operations with general or loco-regional anaesthesia in order to evaluate possible risk factors. Preoperative evaluation has shown coexisting cardiovascular and respiratory diseases in 68% of patients. Treatment of functional decline of organ malnutrition and dehydration and use of adequate anaesthesiology management contributed to contain postoperative morbidity and mortality compared with other analogue experiences. The authors conclude that elderly age, although is a risk factor, cannot be considered an absolute contraindication to major surgery. However physiopathological modification of the elderly must be evaluate.

[The use of subarachnoid bupivacaine analgesia in malignant hyperthermia-susceptible subjects. A clinical case report]. / Impiego dell'analgesia subaracnoidea con bupivacaina in soggetti suscettibili di ipertermia maligna. Descrizione di un caso clinico.

The authors report a case of malignant hyperthermia in susceptible woman undergoing safenectomy. Spinal anesthesia with bupivacaine was performed after dantrolene prophylaxis per os. No complications occurred during and after surgery. This case confirms the safety of local anesthetics and it suggests that anaesthesia should not be refused to caffeine halothane contracture test positive patients.