Effect of general and epidural anaesthesia on thyroid hormones and immunity in neonates.

BACKGROUND: The aim of this study was to verify if variations of thyroid hormones related to circumstances of delivery and mode of maternal anaesthesia can contribute to neonatal neutrophil respiratory burst and natural killer cell activity. METHODS: We evaluated 10 infants born by vaginal delivery (group A), 10 infants born by caesarean section after epidural anaesthesia with lidocaine (group B) and 10 infants born by caesarean section after general anaesthesia with sevoflurane (group C). RESULTS: A significant reduction of neutrophil respiratory burst test was found in groups A and C compared with group B. Natural killer cell (NK) activity with an effector : target ratio of 30 : 1 (NK30) and 10 : 1 (NK10) was significantly higher in group A compared with the B and C groups. In addition, thyroid stimulating hormone (TSH) concentration was significantly reduced in group A compared with the B and C groups. A significant negative correlation was found between TSH and NK30 or NK10. CONCLUSIONS: Our results suggest that the mode of delivery and anaesthesia can significantly modify the endocrine-immune system in the newborn. Caesarean section delivery with regional anaesthesia seems to produce fewer modifications of neonatal immune function compared with general anaesthesia.

[Single lung transplantation retrospective analysis of intraoperative cardiovascular problems]. / Trapianto di polmone singolo. Analisi retrospettiva delle problematiche cardiovascolari intraoperatorie.

BACKGROUND: Analysis of haemodynamic problems during single-lung transplantation and of methodologies employed for their treatment. DESIGN OF THE STUDY: clinical retrospective study. SETTING: General University Hospital. PATIENTS: patients with irreversible lung disease, either parenchymal or vascular, undergoing single lung transplantation. INTERVENTIONS: recording of circulatory failure episodes and treatment with pharmacologic support or cardiopulmonary bypass. Modifications occurring during the study period with respect to drugs administered. Evaluation of the consequences of cardiopulmonary bypass on the postoperative outcome, namely on the duration of mechanical ventilation and length of stay in the intensive care unit. RESULTS: During the last 9 years 69 single-lung transplantations have been performed. In 50% of cases a pharmacologic support has been employed; the drug association dobutamine/nitroprusside has been gradually replaced by the association norepinephrine/nitric oxide for the treatment of right ventricular failure. Twenty patients required cardiopulmonary bypass and this caused a significant increase of the duration of mechanical ventilation and length of stay in the intensive care unit. CONCLUSIONS: Hemodynamic changes during lung transplantation are complex and often severe, leading to a clinical status of right ventricular failure, that sometime requires a mechanical circulatory support. The introduction of nitric oxide in clinical practice significantly contributed to the optimization of intraoperative cardiocirculatory profile of patients, leading to a reduction in the use of vasoactive drugs and cardiopulmonary bypass.

Can anesthesiologic strategies for caesarean section influence newborn jaundice? A retrospective and prospective study.

RATIONALE AND OBJECTIVES: Neonatal jaundice is a frequent problem in neonatology and can be influenced by many factors. Our study arose from the clinical observation that among all newborns delivered by caesarean section in our center, some had a more intense physiological jaundice. We began by reviewing clinical anesthesiological case-sheets to ascertain whether this difference was linked to the use of different anesthesiologic strategies. We then performed a prospective study on healthy preterm and term newborns to verify this hypothesis. STUDY DESIGN: We retrospectively considered all healthy term newborns with weight > 2,400 g delivered by caesarean section from January 1998 to May 1999. In the prospective studies we included healthy term and preterm newborns consecutively delivered by caesarean section from May 1999 to December 1999. We excluded preterm newborns with gestational age < 31 weeks and with weight < 1,400 g. RESULTS: Both in retrospective and in prospective studies anesthetic agents employed were isoflurane (A), sevoflurane (B), or bupivacaine (C). The statistical comparison of the three groups in retrospective study confirmed the clinical observation: the total bilirubin levels were significantly higher in the isoflurane group than in the sevoflurane group (p = 0.0000) and bupivacaine group (p = 0.0002). Analysis of data from the prospective study on term newborns confirmed our previous results. In preterm infants total bilirubin is statistically higher in group A starting from 96 h postdelivery. CONCLUSIONS: It is likely that anesthetic technique can be included among factors with possible influence on neonatal jaundice.

Does ethnicity predict lactation? A study of four ethnic communities.

Human lactation is influenced by a variety of interrelated factors. The purpose of the study was to see whether the racial/ethnic factor is predictive of the onset of lactation and of the volume of breast milk. We planned a prospective study enrolling 269 women who were classified into four ethnic groups: Group 1 Arabs, Group 2 Africans, Group 3 Eastern Europeans, Group 4 Italians. Data regarding the women's habits, medical history and pregnancy were collected. After delivery we recorded the onset of lactogenesis and volume of milk output up until the fifth post-delivery day. A Cox model was fitted in order to assess the independent role that ethnicity has on the time to lactation; a general linear model was used to relate ethnicity to the overall amount of milk produced. Mean age was 27 years and was similar in all groups; half of the women were primiparae. All babies were exclusively breast-fed. Median time to lactation was 36 hours (20-36) and the median daily amount of milk produced was 173.5 ml (119-215). The earliest onset of lactation and the highest milk output was registered among Arab and Eastern European women. On Cox regression analysis ethnicity appeared to be an independent predictor of earlier lactogenesis: breast milk output occurred significantly earlier in the immigrant population than it did in the Italian population. No difference was observed among the immigrants. The multiple regression model showed that ethnicity independently predicts the overall amount of milk production: the Immigrant population produced a significantly higher milk output than the Italian population. No differences were observed within the immigrant groups. Ethnicity has been shown to be associated with the characteristics of breast-feeding. Further research is needed to understand the underlying mechanism.

Case reports in anesthesiology: their trend through 17 years.

UNLABELLED: The study objective was to delineate the trend of case reports (the simplest of the descriptive forms of study) in the anesthesiological literature by analyzing the frequency of publication, and citation, and especially of the place of citation of a sample of published case reports. It is our opinion that case report in anesthesia is particularly suitable for this specialty rather than for others and is often the first signal of a complication, an adverse event, an anesthetic problem in rare disease and alerts other anesthesiologists to the possibility of unexpected events. METHODS: We analyzed the case reports published on an Anesthesiological journal placed in the middle in term of Impact Factor, from January 1980 to December 1997. Citations of each case report were obtained using computer searches of the Science Citation Index (SCI). For each of these case reports we collected in a custom-designed data base the following data: year of publication, number of authors, number of citations per year, place of citation, type of article quoting the case report, number of self-citations, year of first citation. MAIN RESULTS: We identified 637 case reports and 1946 citations. The number of case reports increased through the years up to a peak in 1994-95 and the same trend was observed for citations and self-citations, the number of authors per case report was < or = 4 in 90.4%; 74.2% of total case reports cited were first cited within two years of publication, while 34.7% were never cited. The type of article quoting the case reports has been, in the majority of cases, an original article. CONCLUSIONS: The analysed case reports and the number of citations can give us information about the importance of a clinical situation at a particular time.

Impact of the Hawthorne effect in a longitudinal clinical study: the case of anesthesia.

Clinical research can be influenced by many factors that are capable of invalidating results, and one of these factors is known as the Hawthorne effect: the mere awareness of being under observation can alter the way in which a person behaves. In experimental research this effect can be the undesired effect of the experiments themselves, and the stronger its presence, the greater it can influence the results. In anesthesia practice, owing to the particular emotional condition of a patient facing a surgical operation, the Hawthorne effect could be especially strong. The aim of our study was to show the impact that the knowledge of being included in a study has (Hawthorne effect), by comparing the postoperative changes in psychological well-being in two groups of patients undergoing knee arthroscopy and receiving different information about the study from the anesthetist during the preoperative interview. Other signs and symptoms such as postoperative knee pain, nausea, vomiting (the most feared occurrences), headache, return of spontaneous diuresis, analgesic request, anesthesia complications, as well as the intensity of anxiety were also assessed as secondary endpoints. Our results show that subjects who were aware that they were part of a study scored significantly better on postoperative measures of psychological well-being and postoperative knee pain, compared to subjects who were unaware. The size of the effect, as measured by the odds ratio, remains unchanged when controlling for potential confounding factors. The study has enabled us to demonstrate the presence of the Hawthorne effect in clinical research. Therefore, the Hawthorne effect should be acknowledged and accounted for in the design of a study and in the interpretation of results.

Natural killer cell activity and delivery: possible influence of cortisol and anesthetic agents. A study on newborn cord blood.

The aim of this study was to evaluate the influence of the method of delivery, the level of cord blood lidocaine, and the cortisol concentration on the cord blood natural killer (NK) activity in the full-term healthy newborn. We studied healthy newborns delivered by elective cesarean section without labor under general anesthesia (n = 24), delivered by cesarean section under epidural anesthesia (n = 21), and delivered vaginally with uncomplicated labor (n = 19). The NK cell activity was significantly lower in newborns delivered by cesarean section under epidural anesthesia than it was in the general anesthesia group, while it was similar to the levels found in vaginally delivered newborns. The cortisol concentration was highest in the vaginal delivery group (589.2 +/- 200 mmol/l) and lowest in the general anesthesia group (199.2 +/- 81.9 mmol/l). The mean serum lidocaine concentration was 414.1 +/- 370 microgram/l in the epidural anesthesia group and undetectable in the other groups. In conclusion, our data suggest that the cord blood NK activity was significantly influenced by the method of delivery. This effect could be related to anesthetics given to the mother for general or epidural anesthesia or to the endocrine-metabolic variations observed after different degrees of delivery-related stress. The NK cells being a first-line defense mechanism against viral infections, the results of this study suggest an association with the occurrence of early perinatal infections, especially in preterm infants.

Anesthesia with sevoflurane in bariatric surgery.

BACKGROUND: Sevoflurane is a good halogen agent for bariatric surgery anesthesia because of its physical and chemical characteristics and its repartition coefficient (blood/gas = 0.65). METHOD: From November 1997 to April 1998, 98 bariatric surgery procedures with sevoflurane anesthesia were done: 17 lipectomies, 71 vertical gastroplasties, and 10 biliopancreatic diversions in 71 women and 27 men, average age 30.3+/-8.3 years, with body mass index 43.9+/-5.7. The average operating time was 50+/-15 minutes for vertical gastroplasty, 160+/-20 minutes for biliopancreatic diversion, and 80+/-12 minutes for lipectomy. The technique of anesthesia was as follows: preanesthesia with atropine sulfate 0.01 mg/kg (dosage refers to ideal weight), ranitidine 50 mg, fentanyl 0.1 mg, ketorolac 60 mg; induction with propofol 0.5-1 mg/kg, succinylcholine 1 mg/kg; orotracheal intubation; maintenance with O2-N2O 50%, sevoflurane 1% to 1.5%, actracurium 0.5 mg/kg (dosage refers to ideal weight); awakening and decurarization with atropine sulfate 1 mg and prostigmine 2 mg. RESULTS: This method permitted correct control of the anesthesia, a quick awakening with a low incidence of nausea and vomiting, a prompt regain of physical and psychological functioning, an early discharge from the hospital, and a larger turnover of patients with lower costs. CONCLUSION: Sevoflurane balanced anesthesia seems to be the best anesthesiologic method for bariatric surgery.

Unexpected finding of barium sulphate on the surface of a microspinal catheter.

During a study with a scanning electron microscope to evaluate the structure of microspinal catheter after its removal from subarachnoid space, we found an unusual case. The observation with the microscope of the tip of a catheter removed at the end of an operation for hip replacement in a old female showed the presence of grounded particles with a crystal shape covering the outer surface. Further analysis of this material with an Energy-Dispersive Spectrometer (EDS) showed that it was barium. The patient performed a large bowel barium enema 8 months earlier for a painful syndrome to the lower abdomen. Authors rule out the contamination from the skin and suggest two possible mechanisms of passage of barium from blood to cerebrospinal fluid (CSF) and so to the surface of the catheter.

Is there a bilateral block of the thoracic sympathetic chain after unilateral intrapleural analgesia?

UNLABELLED: This study was designed to ascertain, by telethermography and clinical observation, the effect of injecting anesthetic solutions into the intrapleural space on thoracic sympathetic chains and splanchnic nerves. We studied 15 patients with neoplastic (n = 8) or benign (n = 7) pain, divided into three groups of 5 patients each. The first group received 20 mL of bupivacaine 0.25% in the intrapleural space, the second received 20 mL of bupivacaine 0.5%, and the third received 20 mL of isotonic sodium chloride solution. Each patient was examined telethermographically 30, 60, 90, and 120 min after the blockade. Visceral pain intensity was measured in eight patients using a visual analog scale. Patients receiving bupivacaine had a uniform bilateral increase of cutaneous temperature (+2 degrees C). In those with diffuse visceral pain, the mean value of the pain score decreased from 82 +/- 10 mm at the time of injection to 16 +/- 5 at 120 min. We conclude that intrapleural bupivacaine 0.25% and 0.5% results in bilateral blockade of the thoracic sympathetic chain and also of the splanchnic nerves, which pass in front of the spinal column between the two thoracic sympathetic chains. Our data indicate that intrapleural analgesia can be used in the treatment of not only unilateral visceral and somatic pain, but also diffuse abdominal visceral pain. The bilateral increase of the cutaneous temperature of the trunk (measured telethermographically) and the reduction of the diffuse visceral pain suggest a bilateral block of the sympathetic chain and of the splanchnic nerves. IMPLICATIONS: We subjected 10 patients to monolateral intrapleural analgesia. Five other patients served as controls. The bilateral increase of the cutaneous temperature of the trunk (measured telethermographically) and the reduction of the diffuse visceral pain suggest a bilateral block of the sympathetic chain and of the splanchnic nerves. Our data indicate that intrapleural analgesia can be used in the treatment of not only unilateral visceral and somatic pain, but also diffuse abdominal visceral pain.

The influence of race on breast feeding.

We evaluated the beginning of lactogenesis and the milk quantity until the fifth post-delivery day, before discharge, in 10 primiparae and 11 pluriparae Gypsies, as compared to 12 primiparae and 11 pluriparae Italian women. The results showed that both in primiparae and in pluriparae Gypsies, the lactogenesis started significantly earlier and the milk quantity was significantly greater than in Italian women.

[A method for the evaluation of resource use in cardiac surgery: application of the ICR beta in an Italian reality]. / Un metodo per la valutazione del consumo di risorse in cardiochirurgia: applicabilità dell'IRC beta in una realtàa italiana.

The decreased availability of economic resources requires the use of methods to assess hospital efficiency. The aim of our study was to retrospectively evaluate the applicability to the Italian reality of a catalogue of medical acts (CdAM-champs beta) set up for the French Health System. We wanted to evaluate the amount of resource utilization of a Cardiothoracic Operating Room of a IRCCS regional general hospital. The study included 83 admissions, occurring in October 1996, to the cardiac surgery department. Medical acts were recorded for all admissions taking into account both the number of acts and the weight of acts expressed as standard cost index or ICR. This takes into account the use of human (medical and nursing staff) and technical resources. Calculation of ICR beta scores was achieved by means of two different expressions. We observed a lack of correlation between the two values of each ICR. The previous formula (1991) gives more emphasis on the different conditions in which the operation was carried out (American Society of Anesthesiology score), duration of anesthesia and patients disease with a statistical significant difference. The last formula (1995) only evaluate patients' disease. None of the two formula of ICR beta turns out to be completely appropriate index of resource utilization during anesthesia; therefore this analysis still remains a difficult problem. Yet it must be recognized that this system deserves the merit of having evaluated the anesthesiological duties, by separating them from the surgical ones.

Aortic arch surgery: retrospective analysis of outcome and neuroprotective strategies.

OBJECTIVE: To review intra- and postoperative data regarding surgical reconstruction of the aortic arch performed at our cardiosurgical centre during the past four years, and thus to deepen understanding of neurologic morbidity and of what constitutes the most effective neuroprotection. EXPERIMENTAL DESIGN: Retrospective study. SETTING: Regional University Hospital. PATIENTS: 29 patients who underwent reconstruction of aneurysm or dissection of the aortic arch. Intervention. Surgical replacement of the diseased aorta during deep hypothermia, alone or with selective cerebral perfusion (antegrade or retrograde). MEASURES: Overall mortality rate, neurologic morbidity rate, duration of extracorporeal circulation, of hypothermic circulatory arrest or of selective cerebral perfusion. Evaluation of the importance to neurological outcome of age, modality of operation (emergency or routine), biochemical parameters (glycemia, hematocrit) and perfusion technique. Recording of postoperative time of arousal, and possible correlation with length of selective cerebral perfusion. RESULTS: We observed a mortality rate of 39% (11 deaths) and a neurologic morbidity rate of 34%. Hypothermic circulatory arrest alone did not assure valid neuroprotection (5 cases, all with severe neurologic impairment), while better results were obtained with selective cerebral perfusion, especially antegrade (14 cases, with only 7% of neurologic morbidity rate). Hyperglycemia (>250 mg%) proved to be significantly associated (p=0.002) with increased incidence of adverse neurologic outcome, and the same association was observed between emergency status and adverse neurologic outcome (p=0.002). Moreover, we found an unexpected linear correlation between time of selective cerebral perfusion and postoperative time of arousal (r=0.728, p=0.000). CONCLUSIONS: Deep hypothermic circulatory arrest with selective cerebral perfusion currently represent a valid therapeutic option for brain preservation during reconstruction of the aortic arch in adults. It is mandatory to carry out a tight control of perfusion parameters (flow, pressures and temperature gradients) and biochemical variables (avoidance of hyperglycemia and modified ultrafiltration for fluid balance).

Effect of lidocaine on neutrophil chemotaxis in newborn infants.

Anesthetic drugs can influence the immune system, particularly granulocyte function. The goal of the present study was to evaluate if lidocaine used for epidural anesthesia during cesarean section can influence neonatal neutrophil chemotaxis. We measured chemotaxis and plasma cord lidocaine and cortisol levels in (A) 15 infants born by cesarean section with epidural anesthesia, (B) 15 infants born by vaginal delivery, and (C) 20 infants born by cesarean section with general anesthesia. Chemotaxis levels were significantly lower in group A infants (35.5 +/- 16.1 microns) compared to groups B (54.6 +/- 10.5 microns) and C (71.4 +/- 23 microns). The highest cortisol levels were observed in vaginally delivered infants. A significant inverse relationship was observed between chemotaxis and lidocaine levels (r = -0.6, P = 0.016) in infants born by cesarean section after epidural anesthesia, while no significant correlation was observed between chemotaxis and cortisol level. In conclusion, lidocaine, transferred through the placenta to the fetus during epidural anesthesia, may have an inhibitory effect on chemotaxis.