Morphological variability of black bullhead Ameiurus melas in four non-native European populations

External morphology in black bullhead Ameiurus melas, a fish species considered to have high invasive potential, was studied in its four non-native European populations (British, French, Italian and Slovak). The aim of this study was to examine this species' variability in external morphology, including ontogenetic context, and to evaluate its invasive potential. Specimens from all non-native populations reached smaller body size compared to individuals from native populations. Juvenile A. melas were found to have a relatively uniform body shape regardless of the population's origin, whereas adults developed different phenotypes depending upon location. Specimens from the U.K., Slovak and French populations appeared to be rather similar to each other, whereas the Italian population showed the most distant phenotype. This probably results from the different thermal regime in the Italian habitat. Ameiurus melas from non-native European populations examined in this study showed some potential to alter the body shape both within and between populations. The phenotypic plasticity of A. melas, however, was not found to be as significant as in other invasive fish species. The results suggest that morphological variability itself is not necessarily essential for invasive success. The invasiveness of A. melas is therefore probably favoured by variations in its life-history traits and reproduction variables, together with some behavioural traits (e.g. voracious feeding and parental care) rather than by phenotypic plasticity expressed in external morphology.

Empirical standard mass equation for Salmo marmoratus

Total length (L(T)) (range 24-1000 mm; mean ±S.E. = 170.21 ± 0.36 mm) and mass (W) (range 0.10-9590 g; mean ±S.E. = 76.03 ± 0.87 g) of 36,460 specimens of marble trout Salmo marmoratus were used to compute a standard mass (W(s)) equation for this species by means of the empirical percentile (EmP) method. The EmP W(s) equation calculated was: log(10) W(s) = -5.208 + 3.202 log(10) L(T) - 0.046 (log(10) L(T))(2) (L(T) range 90-570 mm) and it is valid throughout the species' area of distribution across Europe.

Neuromuscular block in Italy: a survey of current management

BACKGROUND

Little is known about current use of neuromuscular blocking agents by Italian anesthetists. This paper reports the results of a survey conducted to obtain information about current management of neuromuscular block in Italy.

METHODS

A questionnaire was given to Italian Anesthetists attending the 64nd National Congress of the Italian Society of Anesthesia, Intensive Care, Analgesia and Intensive Therapy S.I.A.A.R.T.I. (Parma, 13th-16th October 2010). Collected data were stratified by age, geographical location, and the total number of surgical procedures performed in the hospitals concerned.

RESULTS

One thousand four hundred forty patients correctly compiled questionnaires were collected. 50% of respondents used clinical tests to monitor the level of neuromuscular blockade. The main clinical tests cited for the evaluation were: keeping the head lifted up for 5 seconds, protruding the tongue and opening the eyes. Train-of-four was used by 50% of respondents on a routine basis. Only 33% of anesthetists reply that a train-of-four ratio of 90% or more is the safe level prior to extubation.

CONCLUSION

Clinical signs are used by most of the Italian anesthetists to assess the recovery from neuromuscular blockade. There is poor awareness about their inability to indicate even a significant degree of residual neuromuscular block. A more extensive use of quantitative instrumental monitoring is required for the more rational use of neuromuscular blocking agents.

Goal-directed therapy in anesthesia: any clinical impact or just a fashion?

Goal-directed therapy (GDT) describes the protocolized use of cardiac output and related parameters as end-points for fluid and/or inotropic therapy administration. Identifying the patient who will benefit from it has implications throughout perioperative management. The fundamental principle behind GDT is optimizing tissue perfusion by manipulating heart rate, stroke volume, hemoglobin and arterial oxygen saturation to improve oxygen delivery by using fluids, inotropes, red blood cells and supplementary oxygen. Although cardiac output and SvO2 were previously measured using the pulmonary artery catheter, a number of less invasive methods are now available. For intraoperative GDT, the esophageal Doppler-derived Flow Time correct (FTc) is the parameter used most frequently, although other parameters such as stroke volume obtained from Vigileo, PICCO and/or LiDCO, mixed and/or central venous oxygen saturation (SvO2/ScvO2), oxygen delivery and global end diastolic volume (PiCCO system) may be applied in daily clinical practice. The correct target to be followed during the intraoperative period must be clearly established. Most parameters depend primarily on O2 consumption and are not reliable or useful during anesthesia. To date, the quantity and the type of fluids to administer during major elective surgery remain an object of continuing debate. In conclusion, in terms of evidence-based medicine, GDT during anesthesia has a clinical impact when performed using an FTc-based fluids algorithm protocol. In contrast, GDT can be considered unreliable if confusing targets such as SvO2 or ScvO2 higher than 70% during anesthesia are followed.

Knowledge of residual curarization: an Italian survey

BACKGROUND

The use of neuromuscular blocking agents (NMBAs) is widespread in anesthetic practice; little is known about the current use of these drugs in Italy. This survey was conducted to obtain information about the most commonly used clinical tests and the train-of-four (TOF) ratios that are considered as being reliable for assessing recovery from neuromuscular blockade at the end of anesthesia and the estimated occurrence rates of post-operative paralysis in Italian hospitals.

METHODS

The questionnaire was given to Italian anesthesiologists attending the 62nd National Congress of the Italian Society of Anesthesia, Analgesia and Intensive Therapy. Collected data were stratified by age and the total number of surgical procedures performed in the hospitals concerned.

RESULTS

Seven hundred and fifty-four correctly compiled questionnaires were collected (response rate 88.7%). Seventy three percent of the respondents only used clinical tests for monitoring the level of neuromuscular blockade. The main clinical tests cited for the evaluation of residual paralysis were keeping the head lifted up for 5 s, protruding the tongue and opening the eyes. TOF was used by 35% of the respondents on a routine basis. Only 24% of the interviewed anesthesiologists reported that before extubation, a TOF ratio of at least 0.9 should be reached.

CONCLUSIONS

Most Italian anesthetists assess the recovery from neuromuscular blockade only by clinical signs. There is poor awareness about the inability of such techniques to indicate even a significant amount of residual neuromuscular block. A more extensive use of quantitative instrumental monitoring is required for the more rational use of NMBAs.

Perioperative considerations in HIV-infected liver transplanted patients

The introduction of highly active antiretroviral therapy (HAART) has improved survival in HIV patients, allowing them to undergo liver transplantation (OLT) in cases of end-stage liver disease. HIV patients show a higher incidence of pulmonary hypertension. The aim of this study was to evaluate pulmonary and systemic hemodynamic changes in HIV-infected patients compared with a non-HIV-infected group of patients undergoing OLT.

METHODS

We analyzed 20 HIV-infected patients and 20 non-HIV-infected patients who underwent OLT. We analyzed preoperative cardiovascular status, as well as intra- and postoperative hemodynamic data. Hemodynamic data were recorded at 4 predefined phases during OLT and at 24, 48, and 72 hours after intensive care unit (ICU) admission. We also evaluated the following perioperative aspects: transfusion requirements, postoperative mechanical ventilation time, ventilation time, and length of ICU and of hospital stay.

RESULTS

HIV-positive patients were younger than controls with a greater incidence of coinfection with hepatotropic viruses. One HIV-infected patient died in the ICU. Hemodynamic data showed a higher cardiac index and higher pulmonary vascular resistance index among HIV-infected patients, but without any clinical impact. No significant difference in blood unit transfusions, postoperative time on mechanical ventilation, or length of ICU or hospital stay was observed between the groups.

CONCLUSIONS

Although the number of patients studied is limited, we concluded that HIV-infected patients undergoing OLT showed similar perioperative courses as non-HIV-infected patients.

A novel approach to reversal of neuromuscular blockade

Postoperative residual curarization is still a problem of the modern anesthesia. Neostigmine is not the safest drug that allows a safe decurarization, especially when neuromuscular transmission monitoring is not used. Sugammadex is a A-cyclodextrin designed to encapsulate rocuronium bromide, providing a rapid reversal of neuromuscular blockade. It has not cardiovascular, respiratory and cholinergic effects. It has been used in renally impaired patients with no neuromuscular blockade recurrence. Sugammadex reverses either a shallow or a deep neuromuscular block. Volatile agents such as sevoflurane seems not to influence the sugammadex ability to reverse the rocuronium neuromuscular blockade. There is no difference in the sugammadex pharmacokinetic in children and adults. Sugammadex would be able to have a role in the future in reversing a non depolarizing steroidal neuromuscular block.

Inhaled aerosolized prostaglandin E1, pulmonary hemodynamics, and oxygenation during lung transplantation

BACKGROUND

The use of inhaled aerosolized prostaglandin E(1) (aerPGE(1)), a pulmonary vasodilator, has not been widely analyzed. In contrast to prostacyclin, PGE(1) has a shorter lifetime and is metabolized in a greater amount from the lungs, lowering the risk of systemic effects. The aim of this study was to analyse the effects of aerPGE(1) administration on pulmonary hemodynamics and oxygenation during lung transplantation.

METHODS

Eighteen patients undergoing lung transplantation were enrolled in this study. During the first lung implantation, systemic and pulmonary hemodynamic and oxygenation data were evaluated in three phases: -- baseline in 100% O(2); during aerPGE(1) -- after 15 min of aerosolized prostaglandin E(1) administration in 100% O(2); after aerPGE(1) -- 15 min after the end of the prostaglandin E(1) administration in 100% O(2).

RESULTS

During aerPGE(1) a reduction in mPAP, PVRI, and Qs/Qt and an increase in PaO(2)/FiO(2) were observed. Soon after prostaglandin inhalation was ceased, the mPAP, the PVRI, and the Qs/Qt increased while PaO(2)/FiO(2) decreased. During the study, no significant difference in systemic pressure among the phases was noted. A high correlation between changes in mPAP, Qs/Qt and PaO(2)/FiO(2) after aerPGE(1) administration and baseline values was observed. ROC curve analysis showed that values of 40 mmHg of mPAP, 21.7% of the pulmonary shunt, and 364 mmHg for PaO(2)/FiO(2) predict a decrease in mean pulmonary arterial pressure and pulmonary shunt or an improvement in oxygenation of 10% with respect to baseline values.

CONCLUSION

A low dose of aerosolized prostaglandin E(1) decreases pulmonary arterial pressure and improves oxygenation without impairment on systemic hemodynamics, also during anesthesia for lung transplantation. The effect seems to depend on baseline values, which can be considered to be a predictor of the prostaglandin response.

The liver transplant recipient with cardiac disease

Liver transplantation is a stressful condition for the cardiovascular system of patients with advanced hepatic disease. The underlying hemodynamic and cardiac status of patients with cirrhosis is crucial to determine which patients should became recipients. Generally preoperative cardiovascular testing is performed on potential candidates who are more than 45 years old, or have diabetes mellitus, or peripheral vascular disease, or more than two standard cardiac risk factors. Recent data suggest that the prevalence of coronary artery disease among patients with cirrhosis is much greater than previously believed; it likely mirrors or exceeds the prevalence rate in the healthy population. The morbidity and mortality of patients with coronary artery disease who undergo orthotopic liver transplantation (OLT) without treatment are unacceptably high. In conclusion, accurate preoperative cardiac evaluation according to the new American Heart Association & American College of Cardiology should lead to detect and treat coronary artery disease before liver transplantation. In case of alcohol-related cardiomyopathy, portopulmonary hypertension, and hypertrophic cardiomyopathy, there should be a case-by-case discussion by the hepatologist and cardiologist to consider the patient for liver transplantation. No robust data are available on the impact of decompensated dilated heart failure in this setting. If a recipient with cardiac disease is scheduled for OLT, we strongly suggest advanced intra- and postoperative hemodynamic monitoring plus transesophageal echocardiography.

Fenoldopam mesylate and renal function in patients undergoing liver transplantation: a randomized, controlled pilot trial

To test the relative effects on serum creatinine (CRE), blood urea nitrogen (BUN), and urine output of small-dose dopamine and fenoldopam in patients undergoing liver transplantation, we randomized 43 patients to 1 of 2 continuous infusions over 48 h, starting with anesthesia induction: fenoldopam, 0.1 microg . kg(-1) . min(-1) or dopamine, 2 microg . kg(-1) . min(-1). We used predetermined hemodynamic and intravascular volume goals (intrathoracic blood volume index 800-1000 mL/m(2), extravascular lung water index <7 mL/kg) to manage patients with an algorithm for use of mannitol and furosemide to maintain urine output >1 mL . kg(-1) . h(-1). At postoperative day 3, the median CRE increase was 0.2 mg/dL (interquartile range [IQR] -0.2-0.5) with fenoldopam and 0.5 mg/dL (IQR 0.3-0.9, P = 0.004) in the dopamine group. The BUN increase was median 2 mg/dL (IQR -2-8) versus 8.5 mg/dL (IQR 5-12, P = 0.01), respectively, with fenoldopam versus dopamine. Urine output was similar; however, significantly fewer fenoldopam patients required furosemide compared with dopamine patients (median 1 [IQR 0-3] versus 3 [IQR 2-4], respectively, P = 0.003). The hemodynamic effects of dopamine and fenoldopam were similar. Compared with dopamine, in the setting of liver transplantation, fenoldopam is associated with better CRE and BUN values.

Atracurium, cisatracurium, vecuronium and rocuronium in patients with renal failure

AIM

The cumulative index, the recovery, the onset and the duration of action, of atracurium, cisatracurium, vecuronium and rocuronium in uremic patients undergoing kidney transplantation compared to healthy patients undergoing general surgery were studied.

METHODS

In all patients (64 uremic vs 62 "healthy" patients) after anesthesia induction, atracurium 0.5 mgxkg(-1) or cisatracurium 0.15 mgxkg(-1) or vecuronium 0.1 mgxkg(-1) or rocuronium 0.6 mgxkg(-1) were administered, and at the end of surgery when T1 reached 25% neostigmine 0.05 mgxkg(-1) was given. Neuro-muscu-lar transmission was monitored by accelerometry (TOF-GUARD, Organon).

RESULTS

Cumulative index of vecuronium (1.3+/-0.1 vs 1.06+/-0.11, p<0.001) and rocuronium (1.45+/-0.18 vs 1.04+/-0.16, p<0.001), recovery index (time of T1 25-75) of atracurium (14.2+/-5 vs 9+/-4, p<0.005), cisatracurium (18.7+/-3 vs 9.1, p<0.001), vecuronium (18.5+/-3 vs 12.5+/-3, p<0.001) and rocuronium (18+/-6 vs 11+/-4, p<0.001) and interval T1 25% to TOF 0.8 of cisatracurium (20.5+/-1.2 vs 16+/-2.1, p<0.001) and vecuronium (27+/-6.3 vs 20+/-3.3, p<0.001) were longer in uremic patients. The onset time and the duration of action of atracurium, cisatracurium, vecuronium and rocuronium were similar in all groups compared to controls one.

CONCLUSION

In patients with renal failure the use of atracurium, cisatracurium, vecuronium and rocuronium is suitable and predictable in terms of onset, and duration of action. Care has to be taken to vecuronium and rocuronium cumulative index. Neuromuscular trasmission has to be always monitored.

Preload and haemodynamic assessment during liver transplantation: a comparison between the pulmonary artery catheter and transpulmonary indicator dilution techniques

BACKGROUND AND OBJECTIVE

Liver transplantation is characterized by several changes in intravascular blood volume due to vasodilatation based on neurohumoral mediators, intraoperative bleeding and anaesthesia technique effects. Today, with the transpulmonary indicator dilution technique, cardiac index (CIart) can be evaluated and preload assessed in terms of the intrathoracic blood volume index (ITBVI). The aim was to analyse in patients undergoing liver transplantation two preload variables, pulmonary artery occlusion pressure (PAOP) and ITBVI with respect to cardiac index (CIpa) and stroke volume index (SVIpa), the correlation between ITBVI and PAOP, and secondary the relationship between the changes (delta) of ITBVI and PAOP and the changes of CIpa and SVIpa, and the relationships between deltaITBVI and deltaPAOP. The reproducibility and precision of all CIart and CIpa measurements were also evaluated.

METHODS

A prospective study was performed in 60 patients monitored with a pulmonary artery catheter and with the PiCCO system. The variables were evaluated with a linear regression model.

RESULTS

Linear regression analysis between ITBVI-CIpa and ITBVI-SVIpa were r2 = 0.47 (P < 0.0001) and r2 = 0.55 (P < 0.0001) respectively, while PAOP poorly correlated to CIpa (r2 = 0.02), SVIpa (r2 = 0.015) and ITBVI (r2 = 0.002). Only changes in ITBVI were correlated with changes in CIpa (delta1, r2 = 0.37; delta2, r2 = 0.32), and SVIpa (delta1, r2 = 0.60; delta2, r2 = 0.47). The mean bias between CIart and CIpa was 0.13 L min(-1) m(-2) (2 SD = 1.04L min(-1) m(-2)) (r2 = 0.86, P < 0.0001).

CONCLUSIONS

In comparison with PAOP, ITBVI seems a more reliable indicator of cardiac preload in patients undergoing liver transplantation.

Post-thoracotomy analgesia: epidural vs intravenous morphine continuous infusion

BACKGROUND

We compared thoracic morphine epidural analgesia (TEA) and I.V. analgesia (IVA) with morphine, in respect to the time to extubation, the quality of postoperative analgesia, side effects, complications, postoperative hospital length of stay in patients having thoracotomy lung resection.

METHODS

We prospectively studied 563 consecutive patients, undergoing thoracotomy (lobectomy, bilobectomy or pneumonectomy), randomized in two groups: TEA 286 patients and IVA 277 patients. In the epidural group, before the induction of anesthesia, continuous infusion of 15 mg of morphine in 250 mL of normal saline at 5 mL/h was started. In the IVA group a continuous infusion of 30 mg of morphine associated with 180 mg ketorolac in 250 mL of normal saline at 5 mL/h was started before the induction of anesthesia. The pain degree was evaluated on an analogic scale by Keele modified at 1 (end of anesthesia) 6, 12, 24, and 48 postoperative hours, at rest and after movements. Data obtained were analysed by means of the analysis of variance for repeated measures.

RESULTS

The time from the end of surgery to tracheal extubation was similar in both groups. Significantly lower numeric verbal pain scores at rest and after movements were found in the epidural group (p<0.001). Postop complications, nausea and vomiting were higher in the IVA group (p<0.05). Postoperative mean hospital length of stay was 9+/-4 days in TEA and 11+/-4 in the IVA group (p<0.05).

CONCLUSIONS

In our study the epidural root was superior in terms of analgesia, side effects, length of stay and postoperative complications after thoracotomy.

Continuous and intermittent cardiac output measurement: pulmonary artery catheter versus aortic transpulmonary technique

BACKGROUND

Cardiac output (CO) can be measured intermittently by bolus thermodilution methods in the pulmonary artery (COpa) or in the aorta (COart). A continuous thermodilution method (CCO) and a method for continuous estimation using the arterial pulse wave (PCCO) are also available.

METHODS

We compared two methods of intermittent CO measurements in patients during liver transplantation: COpa, regarded as the current clinical standard, and an aortic transpulmonary thermodilution technique (COart) performed with the PiCCO system. We also compared CCO and PCCO. Measurements were made in 62 patients at three stages: after the induction of anaesthesia, after caval clamping phase, and at the end of surgery. We used Bland-Altman and correlation analysis.

RESULTS

We found close agreement between the techniques. Mean bias between COart and COpa and PCCO and CCO was 0.15 (2SD of differences between methods=1.74) litre min(-1) and -0.03 (1.75) litre min(-1), respectively. Mean bias between CCO and COpa and PCCO and COpa was 0.02 (1.48) litre min(-1) and 0.04 (1.69) litre min(-1), respectively.

CONCLUSIONS

Measurement with the aortic transpulmonary thermodilution technique gives continuous and intermittent values that agree with the pulmonary thermodilution method.

[Anesthesia for lung volume reduction surgery]

BACKGROUND

Lung volume reduction surgery (LVRS) has become a novel palliative procedure for a subgroup of patients with advanced non-bullous emphysema.

METHODS

Seventy-six patients with severe emphysema were evaluated: ten patients were considered for lung transplantation and only 24 underwent LVRS. In all patients an epidural catheter was inserted between the T5-T9 space. During one lung ventilation (OLV), ventilatory setting was adjusted to avoid air trapping and/or dynamic hyperinflation and high frequency jet ventilation was used when PaO2/ FiO2 was lower than 60 mmHg in 5 patients. Permissive hypercapnia (PaCO2=53 mmHg) was allowed to avoid hyperinflation and reach hemodynamic stability.

RESULTS

During OLV PaO2/FiO2 was 148+/-80 mmHg, PaCO2 53+/-11 mmHg, mPA 27+/-2 mmHg and Qsp/Qt was 38+/-6%. Although the high risk patients, there were no complications due to hypercapnia during surgery. Twenty-three patients were extubated successfully at the end of the surgery (PaO2/FiO2 179+/-34 mmHg and PaCO2 59+/-11 mmHg) and only one patient was not extubated because of air leakage and died for postoperative respiratory failure after 20 days. Another patient died because of sepsis after 15 days. Numeric Ordinal Verbal Scale (by Keele modified) was used for postoperative pain degree at 0, 12th and 24th hours. No patients had pain>2.

CONCLUSIONS

In conclusion, a careful anesthesia technique with an accurate intraop monitoring associated with thoracic epidural analgesia even in Video Assisted Thoracic Surgery is suggested in LVRS patients; 12 months postoperative data confirm the validity of the procedure (FEV1 24 AE 36%, FVC 53 AE 70%, RV 265 AE 199% and 6MWT 213 AE 330 m).

Hemodynamic and oxygenation changes of combined therapy with inhaled nitric oxide and inhaled aerosolized prostacyclin

OBJECTIVE

To evaluate hemodynamic and oxygenation changes of combined therapy with inhaled nitric oxide (iNO) and inhaled aerosolized prostcyclin (IAP) during lung transplantation.

DESIGN

Prospective study.

SETTING

University hospital.

PARTICIPANTS

Ten patients scheduled for lung transplantation.

INTERVENTIONS

Ten patients, with a mean age of 38 years (range, 24 to 56 years), were scheduled for lung transplantation (2 single-lung transplantations and 8 double-lung transplantations). During first lung implantation with single-lung perfusion and ventilation, hemodynamic and oxygenation data were analyzed in 3 phases: (1) baseline, 5 minutes after pulmonary artery clamping; (2) inhaled NO phase, 15 minutes after inhaled NO administration (20 ppm) in 100% oxygen; and (3) IAP-inhaled NO phase, 15 minutes after combined administration of inhaled NO (20 ppm) and IAP (10 ng/kg/min) in 100% oxygen.

MEASUREMENTS AND MAIN RESULTS

During the inhaled NO phase, reductions of mean pulmonary arterial pressure (p < 0.05) and intrapulmonary shunt (p < 0.05) were noted. After the start of prostacyclin inhalation, a further decrease in mean pulmonary arterial pressure (p < 0.05) was observed. PaO2/FIO2 increased during the IAP-inhaled NO phase (p < 0.05), whereas intrapulmonary shunt decreased (p < 0.05).

CONCLUSION

This study confirms the action of inhaled NO as a selective pulmonary vasodilator during lung transplantation. Combined therapy with IAP and inhaled NO increases the effects on pulmonary arterial pressure and oxygenation compared with inhaled NO administered alone without any systemic changes.

Pediatric renal transplantation: anesthesia and perioperative complications

The appropriate choice of anesthesia for patients (pts) undergoing renal transplantation (Ktx) requires minimal toxicity and accurate monitoring for pts at high risk for metabolic, cardiovascular, and respiratory perioperative complications. We evaluated the anesthetic management and postoperative follow-up in pediatric Ktx performed in the last 12 years in our institution. From 1988 to 1999, 75 ASA class II-III pts (45 males, 22 females) younger than 18 years scheduled for Ktx were studied: 49 received a graft from a cadaveric donor (CD) and 26 from a living donor (LD). All pts were treated with dialysis within 24 h before the procedure. Standard monitoring consisted of an electrocardiogram, central venous pressure, non-invasive arterial pressure, pulse oximetry, and inspiratory and expiratory gas analysis. If necessary, an arterial cannula and pediatric pulmonary catheter were introduced. Anesthesia was induced with sodium thiopental, propofol, halothane, or sevoflurane and maintained with isoflurane and/or fentanyl and droperidol in O2:N2O (FiO2 0.4%). As muscle relaxants atracurium or cisatracurium besilate were used, except in allergic pts, in whom vecuronium or rocuronium bromide was administered. Dopamine, 20% mannitol, and furosemide were used to increase diuresis. Continuous morphine and ketoralac infusions were used for postoperative pain relief. The surgical technique was the same in all cases. Complications and renal-function (RF) recovery were evaluated relating to CD and LD using the chi-square test; differences in mean anesthesia and surgical time were evaluated by Student's t-test; survival curves were calculated from the day of Ktx to death or last follow-up and estimated by the Kaplan-Meier method. Values of P below 0.05 were considered significant. Postoperative immunosuppressive therapy was based on cyclosporine together with other conventional drugs. Mean anesthesia time was 228 +/- 65 min. Mean kidney ischemia time for CD was 16.5 +/- 4 h. Four pts (3 CD, 1 LD) died within 72 h postoperatively: 3 due to cardiac failure and 1 to metabolic coma. Six pts showed cardiovascular and 3 had infective complications, all successfully treated. Three pts (2 CD, 1 LD) died within 2 to 12 months after, surgery; 10 (6 CD, 4 LD) had graft failure and are still alive on dialysis; 58 (38 CD, 20 LD) are alive in good health after a mean follow-up of 57.6 +/- 36.6 months (range 12-120 months). Fifteen of 26 pts younger than 12 years (21 CD and 5 LD) recovered RF intraoperatively (10 CD, 5 LD); 1 with CD and 1 with LD showed postoperative graft failure and 2 with CD died within 72 h postoperatively, 22 (18 CD and 4 LD) are alive in good health. This group showed no statistical difference compared to pts older than 12 years. Of 16 pts (15 CD and 1 LD) with body weight (BW) less than 25 kg, 6 showed intraoperative (5 CD, 1 LD) recovery of RF. The 3 deaths were all in CD pts, 2 within 72 h and one 2 months after surgery; only 1 LD had postoperative graft failure. Twelve pts (75%) (12 CD, 80%) are alive in good health. Compared to pts with BW of 25 kg or more, this group showed lower intraoperative recovery of RF (P < or = 0.05). No peri- and postoperative complications occurred in all 26 LD pts (100%). Recent advances in surgery, anesthesia, immunosuppression, and antimicrobial prophylaxis have made Ktx a more predictable procedure even in pediatric pts. For high-risk pts, mortality and morbidity can be controlled by accurate surgical, anesthetic, and postoperative management. Pts younger than 12 years and with BW less than 25 kg are more likely to develop peri- and postoperative complications.

Localization of cerebral arterovenous malformations using digital angiography

Since 1989 we performed stereotactic radiotherapy treatments of cerebral arterovenous malformations (AVM), estimating three-dimensional (3-D) localization and shape of target volumes by the Leksell stereotactic helmet on two orthogonal radiographic projections. Due to the limitations of this method, we developed a new technique for the localization of the target volume using digital subtraction angiography (DSA) and digital image processing. To achieve this result we first developed a method to correct nonlinear distortion of DSA images using spatial relocation of image pixels based on a calibration grid. We then developed an algorithm for localization of the target volume using two independent DSA projections. Target volume coordinates in the helmet system are calculated using two DSA acquisitions taken with a free angle (approximately 90 degrees), one in the AP and the other in the LL direction. The helmet can be freely positioned between the x-ray source and the image plane. The projections of eight reference points inserted in the helmet at a known location, are used to calculate the transformation matrix between the two coordinate systems. We performed numerical and experimental validation of the system. A hypothetical random error (up to 2 mm) on image coordinates of the reference points allowed to determine that the error in target localization was less than 0.2 mm. Using DSA images of target points with a known location within a phantom, the error between calculated and actual location was, on average, 0.30+/-0.13 mm (mean+/-SD), with a maximum error of 0.49 mm. The results of numerical and experimental validations show that the system we have developed allows fast and accurate localization of the center of the target volume and it is suitable for efficient guiding during stereotactic radiosurgery of AVM.

[Anesthesia in single and bilateral sequential lung transplantation. Lung Transplantation Group]

BACKGROUND

Anesthesia for lung transplantation: intraoperative complications and long term results.

METHODS

52 patients were scheduled for 16 single lung transplantations (SLT) (9 fibrosis and 7 emphysema) and 36 bilateral sequential lung transplantations (DLT) (4 bronchiectasis, 6 emphysema, 3 fibrosis, 22 cystic fibrosis and 1 pulmonary hypertension). Anesthesia was induced with propofol or midazolam, and fentanyl or alfentanil. As muscle relaxant vecuronium bromide was used. Anesthesia was maintained with isoflurane, fentanyl in boluses or sufentanil continuous infusion in O2 100%. Prostaglandin E1 (20-300 ng/kg/min), inhaled nitric oxide (10-40 ppm), dobutamine (5-15 mcg/kg/min), norepinephrine (0.05-3 mcg/kg/min) and ephedrine (5-10 mg per bolus) were used for hemodynamic management. In 2 patients inhaled areosolized prostacyclin were administered.

RESULTS

Mean pulmonary arterial pressure (mPA) and pulmonary vascular resistance (PVRI) increased after pulmonary artery clamping during first lung (mPA: 3347 nel DLT, 3643 nel SLT; PVRI; 375488 nel DLT, 377420 nel SLT) and second lung implantation (mPA: 3746; PVRI: 263553) and decreased after reperfusion of the first (mPA: 4737 nel DLT, 4329 nel SLT; PVRI: 488263 nel DLT, 420233 nel SLT) and the second lung (mPA: 4629; PVRI: 553260). Only in 9 cases (7 DLT and 2 SLT) C-P bypass was used.

CONCLUSIONS

With a strong drug support with pulmonary vasodilators, positive inotropic and systemic vasoconstrictor drugs, in most patients we transplanted C-P bypass can be avoided. Intraoperative deaths were not observed. Two years actuarial survival is 65% for DLT and 60% for SLT.

[Hemodynamic changes during continuous infusion with dobutamine in candidates for lung transplantation. Lung Transplantation Group]

BACKGROUND

The aim of this study is to analyze the effects of dobutamine (DBT) on pulmonary and systemic hemodynamics and oxygenation in lung transplant candidates.

METHODS

Forty-five patients (21M, 24F) to be introduced in waiting list for lung transplantation were studied (14 pulmonary fibrosis, 15 COPD, and 16 cystic fibrosis). They were studied awake, while spontaneously breathing in two different phases: baseline--O2 100%; DBT phase--O2 100% after 10 minutes of DBT continuous infusion (10 mcg/Kg/min). Blood gas samples and hemodynamic data were collected during right heart catheterization. Data were statistically analyzed with Student's "t" test and values for p < 0.05 were considered as significant.

RESULTS

During DBT phase, a significant increase of cardiac output with a decreasing in systemic and pulmonary vascular resistance was observed. Since the fall in pulmonary vascular resistance (PVRI) was not proportional to the increase of cardiac output, mean pulmonary artery pressure and transpulmonary gradient increased. The prevalent role of vascular recruitment as mechanism in PVRI reduction during DBT is supported by the concomitant fall in PaO2/FiO2. This strongly suggests a worsening of regional Va/Qc due to an increased perfusion of poorly ventilated areas.

CONCLUSIONS

DBT reduces PVRI through a recruitment of vessels due to an increase of pulmonary flow. Dobutamine has a favorable hemodynamic effect in mild-to-moderate pulmonary hypertension in lung transplant candidates.

Anaesthesia for liver transplantation in cystic fibrosis patients

INTRODUCTION

Cystic fibrosis (CF) is a disease caused by an inherited genetic defect. While pulmonary and pancreatic abnormalities predominate the clinical spectrum, other organ involvement is common, including liver. The severity of liver disease does not appear to be related to the severity of exocrine pancreatic or lung function. We discuss anaesthesia in four CF patients undergoing liver transplantation.

METHODS

We studied haemodynamic and oxygenation modifications during anaesthesia in four patients affected by CF with end-stage liver disease and mild to moderate pulmonary abnormalities. The patients received pancreatic enzyme prior to transplantation and two had insulin-dependent diabetes mellitus. All patients were treated with broad-spectrum antibiotic therapy. After a waiting time ranging one week to three months, all patients were successfully transplanted. General anaesthesia was induced with fentanyl, thiopental and pancuronium, and maintained with isoflurane supplemented by fentanyl in O2:air. Haemodynamic and oxygenation evaluations were made during the main phases of the transplant. After the intubation and at the end of the procedure all patients received a broncho-alveolar toilet through fiberoptic bronchoscopy.

RESULTS

During anaesthesia for liver transplantation, PaO2 increased proportionally to the decreasing of Qs/Qt. In postoperative follow-up, Fev1 and FVC improved from preoperative time in all patients. In conclusion, even if cystic fibrosis is a multisystem disease, liver transplantation can be offered to CF patients with endstage liver disease and mild to moderate pulmonary function abnormalities. The four patients are still alive, enjoying good health. The improved respiratory function and quality of life of these children is remarkable.

Inhaled nitric oxide in patients with cystic fibrosis during preoperative evaluation and during anaesthesia for lung transplantation

INTRODUCTION

Inhaled nitric oxide (iNO) has been recently used as pulmonary vasodilator without any systemic effects because of a rapid inactivation by haemoglobin. We studied haemodynamic and oxygenation effects during iNO administration in cystic fibrotic patients during preoperative evaluation and during anaesthesia for lung transplantation.

METHODS

From March 1996 to November 1997, 35 patients received iNO (40 ppm) during preoperative evaluation in spontaneously breathing. 13 patients, who underwent double lung transplantation, received iNO (40 ppm) during the surgical procedures, after pulmonary artery clamping.

RESULTS

In the preoperative evaluation a significant decrease of mean pulmonary artery pressure, pulmonary vascular resistance index and intrapulmonary shunt, with an increase of PaO2/FiO2, were observed during iNO administration, compared to baseline in 100% O2. During lung transplantation a significant decrease in intrapulmonary shunt was noted. All the transplants were successfully performed without cardio-pulmonary bypass. In all procedures, after iNO administration, we observed no modification of systemic haemodynamics. In conclusion, our study confirms the pulmonary effects of iNO without any systemic effects in patients affected by cystic fibrosis during preoperative evaluation and during anaesthesia for lung transplantation.

[Surgical endoscopy of the airways]

METHODS

Between April 1993 and April 1996, 146 endoscopic procedures were performed in 128 patients (144 with Nd:YAG laser) with benign or malignant obstructions of the airway. Removal of foreign bodies are not included in this series. Twenty resections were performed with the flexible fiberoptic bronchoscope under local anesthesia and 126 with the rigid tube under general anesthesia. Power settings were always between 20 and 35 Watts. Eighteen procedures were performed in emergency. Fifteen patients had a benign postintubation tracheal stricture (20 treatments-11 Dumon stents and 1 Montgomery tube). Eighty-two patients (90 treatments-12 stents) had malignant lesions of the airways (trachea 11, carina 2, RMB 22, LMB 27, TI 11, LULB 3, RULB 2, LILB 4). Laryngeal, tracheal or bronchial granulations were present in 19 patients (21 treatments). Other lesions were present in 11 patients (14 treatments-6 stents).

RESULTS

Major complications occurring during laser resections were bleeding (2), hypoxia (1) and cardiac arrhythmia (2); 2 patients died 24 hours after the procedure for cardio-respiratory failure. The airway calibre was improved in 100% of patients with benign lesions and 82.4% of patients with malignancy. In the latter group the trachea, main stem bronchi and truncus intermedius calibre was improved better than the lobar bronchi. All patients with malignancy underwent chemo-radiotherapy without respiratory distress.

CONCLUSIONS

Nd:YAG laser therapy is a safe and effective mean of releasing airway obstructions; indwelling stents contribute to further improve the results.

Inhaled nitric oxide during anesthesia for bilateral single lung transplantation. Case report

Recently inhaled nitric oxide (iNO) has been used as pulmonary vasodilator without any effect on systemic hemodynamics. iNO has been also used in cardiac and thoracic surgery, involving lung transplantation. In this case report a patient, 41 years old female, affected by bronchiectasis, underwent bilateral sequential single lung transplantation and during one lung ventilation and pulmonary artery clamped iNO allowed to avoid cardiopulmonary bypass and to carry out the procedure successfully.

Hemodynamic and metabolic effects of transjugular intrahepatic portosystemic shunt (TIPS) during anesthesia for orthotopic liver transplantation

Recently, the transjugular intrahepatic portosystemic shunt (TIPS) has been advocated as a safe bridge to orthotopic liver transplantation (OLT). We retrospectively studied 53 consecutive cirrhotic patients who underwent OLT: 27 patients with TIPS were compared to 26 controls. Hemodynamic and oxyphoretic data (Fick method) were collected during six phases of OLT. There were no significant differences in demographic data and Child-Pugh class, nor in surgical time and blood product requirements before the anhepatic phase between TIPS patients and controls. In the TIPS group, we observed a marked hyperdynamic profile with a lower systemic vascular resistance index, higher cardiac index, and depressed oxygen consumption before native liver removal. During the same period, the TIPS group developed a greater acidosis and was treated with a larger amount of NaHCO3. Following the anhepatic phase, no differences between the two groups were detected. All transplantations were successful, and no complications related to TIPS were observed. These results seem to be the consequence of a reduced liver function reserve with a direct hemodynamic effect due to the TIPS.