Oxidative imbalance and muscular alterations in diverticular disease.

BACKGROUND: It is still a matter of debate if neuromuscular alterations reflect a primary event in diverticular disease (DD). AIMS: This study aimed to assess colonic wall layers from both stenotic and non-stenotic complicated DD, bio-phenotypic alterations, inflammatory and oxidative status. METHODS: A systematic analysis of colonic specimens obtained from stenotic and non-stenotic DD specimens was conducted and compared with controls. Biological activity and qPCR analysis were performed on longitudinal and circular muscles. Western blot analysis was performed throughout colonic wall layers to quantify oxidative and inflammatory markers. RESULTS: A homogenous increase in oxidative stress was observed through all the layers, which were more sharpened in the longitudinal muscle for a loss in antioxidant defenses. In both stenotic and non-stenotic colon, the longitudinal muscle presented an impaired relaxation and a cellular phenotypic switch driven by transforming growth factor-ß with an increase in mRNA expression of collagen Iα and a decrease in myosin heavy chain. The circular muscle, as the mucosa, was less affected by molecular alterations. No peculiar increase in inflammatory markers was observed. CONCLUSION: A longitudinal colonic myopathy is present in DD, independently from the disease stage associated with an oxidative imbalance that could suggest new therapeutic strategies.

Comparing the Occurrence of Healthcare-Associated Infections in Patients with and without COVID-19 Hospitalized during the Pandemic: A 16-Month Retrospective Cohort Study in a Hospital Intensive Care Unit.

The COVID-19 pandemic has increased the healthcare-associated infection (HAI) risk in intensive care unit (ICU) patients. However, a comparison between patients with and without COVID-19 in terms of HAI incidence has been rarely explored. In this study, we characterized the occurrence of HAI among patients with and without COVID-19 admitted to the ICU of the Umberto I hospital of Rome during the first 16 months of the pandemic and also identified risk factors for HAI acquisition. Patients were divided into four groups according to their ICU admission date. A multivariable conditional risk set regression model for multiple events was constructed for each admission period. Adjusted hazard ratios and 95% confidence intervals were calculated. Overall, 352 COVID-19 and 130 non-COVID-19 patients were included, and a total of 361 HAIs were recorded. We found small differences between patients with and without COVID-19 in the occurrence and type of HAI, but the infections in the two cohorts mostly involved different microorganisms. The results indicate that patient management was likely an important factor influencing the HAI occurrence during the pandemic. Effective prevention and control strategies to reduce HAI rates should be implemented.

Prior Antibiotic Therapy and the Onset of Healthcare-Associated Infections Sustained by Multidrug-Resistant Klebsiella pneumoniae in Intensive Care Unit Patients: A Nested Case-Control Study.

Epidemiological research has demonstrated direct relationships between antibiotic consumption and the emergence of multidrug-resistant (MDR) bacteria. In this nested case-control study, we assessed whether prior exposure to antibiotic therapy and its duration affect the onset of healthcare-associated infections (HAIs) sustained by MDR Klebsiella pneumoniae (MDR-Kp) in intensive care unit patients. Cases were defined as patients who developed an MDR-Kp HAI. Controls matched on sex and the length of intensive care unit (ICU) stay were randomly selected from the at-risk population. Any antibiotic agent received in systemic administration before the onset of infection was considered as antibiotic exposure. Multivariable conditional logistic regression analyses were performed to estimate the effect of prior exposure to each antibiotic class (Model 1) or its duration (Model 2) on the onset of HAIs sustained by MDR-Kp. Overall, 87 cases and 261 gender-matched controls were compared. In Model 1, aminoglycosides and linezolid independently increased the likelihood of developing an MDR-Kp HAI, whereas exposure to both linezolid and penicillins reduced the effect of linezolid alone. In Model 2, cumulative exposure to aminoglycosides increased the likelihood of the outcome, as well as cumulative exposures to penicillins and colistin, while a previous exposure to both penicillins and colistin reduced the influence of the two antibiotic classes alone. Our study confirms that aminoglycosides, penicillins, linezolid, and colistin may play a role in favoring the infections sustained by MDR-Kp. However, several double exposures in the time window before HAI onset seemed to hinder the selective pressure exerted by individual agents.

The role of damage control surgery in the treatment of perforated colonic diverticulitis: a systematic review and meta-analysis.

INTRODUCTION: Damage control surgery (DCS) is the classic approach to manage severe trauma and has recently also been considered an appropriate approach to the treatment of critically ill patients with severe intra-abdominal sepsis. The purpose of the present review is to evaluate the outcomes following DCS for Hinchey II-IV complicated acute diverticulitis (CAD). METHODS: A comprehensive systematic search was undertaken to identify all randomized clinical trials (RCTs) and observational studies, irrespectively of their size, publication status, and language. Adults who have undergone DCS for CAD Hinchey II, III, or IV were included in this review. DCS is compared with the immediate and definitive surgical treatment in the form of HP, colonic resection, and primary anastomosis (RPA) with or without covering stoma or laparoscopic lavage. We searched the following electronic databases: PubMed MEDLINE, Scopus, and ISI Web of Knowledge. The protocol of this systematic review and meta-analysis was published on Prospero (CRD42020144953). RESULTS: Nine studies with 318 patients, undergoing DCS, were included. The presence of septic shock at the presentation in the emergency department was heterogeneous, and the weighted mean rate of septic shock across the studies was shown to be 35.1% [95% CI 8.4 to 78.6%]. The majority of the patients had Hinchey III (68.3%) disease. The remainder had either Hinchey IV (28.9%) or Hinchey II (2.8%). Phase I is similarly described in most of the studies as lavage, limited resection with closed blind colonic ends. In a few studies, resection and anastomosis (9.1%) or suture of the perforation site (0.9%) were performed in phase I of DCS. In those patients who underwent DCS, the most common method of temporary abdominal closure (TAC) was the negative pressure wound therapy (NPWT) (97.8%). The RPA was performed in 62.1% [95% CI 40.8 to 83.3%] and the 22.7% [95% CI 15.1 to 30.3%]: 12.8% during phase I and 87.2% during phase III. A covering ileostomy was performed in 6.9% [95% CI 1.5 to 12.2%]. In patients with RPA, the overall leak was 7.3% [95% CI 4.3 to 10.4%] and the major anastomotic leaks were 4.7% [95% CI 2.0 to 7.4%]; the rate of postoperative mortality was estimated to be 9.2% [95% CI 6.0 to 12.4%]. CONCLUSIONS: The present meta-analysis revealed an approximately 62.1% weighted rate of achieving GI continuity with the DCS approach to generalized peritonitis in Hinchey III and IV with major leaks of 4.7% and overall mortality of 9.2%. Despite the promising results, we are aware of the limitations related to the significant heterogeneity of inclusion criteria. Importantly, the low rate of reported septic shock may point toward selection bias. Further studies are needed to evaluate the clinical advantages and cost-effectiveness of the DCS approach.

Dermatome Mapping Test in the analysis of anatomo-clinical correlations after inguinal hernia repair.

BACKGROUND: Nerve identification is recommended in inguinal hernia repair to reduce or avoid postoperative pain. The aim of this prospective observational study was to identify nerve prevalence and find a correlation between neuroanatomy and chronic neuropathic postoperative inguinal pain (CPIP) after 6 months. MATERIAL: A total of 115 patients, who underwent inguinal hernia mesh repair (Lichtenstein tension-free mesh repair) between July 2018 and January 2019, were included in this prospective observational study. The mean age and BMI respectively resulted 64 years and 25.8 with minimal inverse distribution of BMI with respect to age. Most of the hernias were direct (59.1%) and of medium dimension (47.8%). Furthermore, these patients were undergoing Dermatome Mapping Test in preoperatively and postoperatively 6 months evaluation. RESULTS: Identification rates of the iliohypogastric (IH), ilioinguinal (II) and genitofemoral (GF) nerves were 72.2%, 82.6% and 48.7% respectively. In the analysis of nerve prevalence according to BMI, the IH was statistically significant higher in patients with BMI < 25 than BMI ≥ 25 P (< 0.05). After inguinal hernia mesh repair, 8 patients (6.9%) had chronic postoperative neuropathic inguinal pain after 6 months. The CPIP prevailed at II/GF dermatome. The relation between the identification/neurectomy of the II nerve and chronic postoperative inguinal pain after 6 months was not significant (P = 0.542). CONCLUSION: The anatomy of inguinal nerve is very heterogeneous and for this reason an accurate knowledge of these variations is needed during the open mesh repair of inguinal hernias. The new results of our analysis is the statistically significant higher IH nerve prevalence in patients with BMI < 25; probably the identification of inguinal nerve is more complex in obese patients. In the chronic postoperative inguinal pain, the II nerve may have a predominant role in determining postoperative long-term symptoms. Dermatome Mapping Test in an easy and safe method for preoperative and postoperative 6 months evaluation of groin pain. The most important evidence of our analysis is that the prevalence of chronic pain is higher when the nerves were not identified.

Tailored Surgery in Inguinal Hernia Repair. The Role of Subarachnoid Anesthesia: A Retrospective Study.

Safety and effectiveness evaluation of subarachnoid anesthesia implemented with hyperbaric Prilocaine in reduced dose (30mg) in combination with Fentanyl (20mcg), for the purpose of ensuring an optimal analgesia in open inguinal hernia repair. Although the local anesthesia is the first line treatment for open inguinal hernia repair, a minority of patients is not eligible because of obesity or big groin hernia, requiring a high dose of local anesthetic. Subarachnoid anesthesia implemented with hyperbaric Prilocaine in reduced dose in combination with Fentanyl may be a good alternative. Thirty patients were treated with intrathecal association of Prilocaine 30 mg and Fentanyl 20 mcg (group PF); they were compared to a group of fifty three ones, previously treated with a classic procedure with intrathecal Prilocaine 60 mg (group P). The sensitive blockage remained within an higher limit at T12 level in the patients of PF group, and a lower limit at S1 level 50 minutes after the anesthesia, while in the P group the anesthetic tended to migrate (p<0.0001). In PF group 70 minutes after the anesthesia 21 patients had a Bromage score equal to 0 and 9 patients equal to 9 (in P group, 19 patients had a score equal to 3, 8 to 2 and 3 to 1, p<0.0001). Subarachnoid anesthesia using Prilocaine 30 mg + Fentanyl 20 mcg could be stated as a viable alternative to local anesthesia in selected patients.

Effectiveness over time of a multimodal intervention to improve compliance with standard hygiene precautions in an intensive care unit of a large teaching hospital.

Background: Standard hygiene precautions are an effective way of controlling healthcare-associated infections. Nevertheless, compliance with hand hygiene (HH) guidelines among healthcare workers (HCWs) is often poor, and evidence regarding appropriate use of gloves and gowns is limited and not encouraging. In this study, we evaluated the ability over time of a multimodal intervention to improve HCWs compliance with standard hygiene precautions. Methods: Trend analysis of direct observations of compliance with HH guidelines and proper glove or gown use was conducted in the medical/surgical intensive care unit (ICU) of Umberto I Teaching Hospital of Sapienza University of Rome. The study consisted of two phases: a six-month baseline phase and a 12-month post-intervention phase. The multimodal intervention was based on the World Health Organization strategy and included education and training of HCWs, together with performance feedback. Results: A total of 12,853 observations were collected from November 2016 to April 2018. Overall compliance significantly improved from 41.9% at baseline to 62.1% (p < 0.001) after the intervention and this improvement was sustained over the following trimesters. Despite variability across job categories and over the study period, a similar trend was observed for most investigations. The main determinants of compliance were job category (with nurses having the highest compliance rates), being a member of ICU staff and whether delivering routine, as opposed to emergency, care. HH compliance was modified by glove use; unnecessary gloving negatively affected HH behaviour while appropriate gloving positively influenced it. Conclusions: The multimodal intervention resulted in a significant improvement in compliance with standard hygiene precautions. However, regular educational reinforcement and feedback is essential to maintain a high and uniform level of compliance.

Postoperative nausea and vomiting (PONV) in outpatient repair of inguinal hernia.

PURPOSE: Nausea and vomiting are among the most frequent complications following anesthesia and surgery. Due to anesthesia seems to be primarily responsible for post operative nausea and vomiting (PONV) in Day Surgery facilities, the aim of the study is to evaluate how different methods of anesthesia could modify the onset of postoperative nausea and vomiting in a population of patients undergoing inguinal hernia repair. METHODS: Ninehundredten patients, aged between 18 and 87 years, underwent open inguinal hernia repair. The PONV risk has been assessed according to Apfel Score. Local anesthetic infiltration, performed by the surgeon in any cases, has been supported by and analgo-sedation with Remifentanil in 740 patients; Fentanyl was used in 96 cases and the last 74 underwent deep sedation with Propofol . RESULTS: Among the 910 patients who underwent inguinal hernia repair, PONV occurred in 68 patients (7.5%). Among patients presenting PONV, 29 received Remifentanil, whereas 39 received Fentanyl. In the group of patients receiving Propofol, no one presented PONV. This difference is statistically significant (p < .01). Moreover, only 50 patients of the total sample received antiemetic prophylaxis, and amongst these, PONV occurred in 3 subjects. CONCLUSIONS: Compared to Remifentanil, Fentanyl has a major influence in causing PONV. Nonetheless, an appropriate antiemetic prophylaxis can significantly reduce this undesirable complication. Key words: Day Surgery, Fentanyl, Inguinal, Hernia repair, Nausea, Vomiting.

Protective Role of Postbiotic Mediators Secreted by Lactobacillus rhamnosus GG Versus Lipopolysaccharide-induced Damage in Human Colonic Smooth Muscle Cells.

BACKGROUND: Some beneficial effects of probiotics may be due to secreted probiotic-derived factors, identified as "postbiotic" mediators. The aim of this study was to evaluate whether supernatants harvested from Lactobacillus rhamnosus GG (LGG) cultures (ATCC53103 strain) protect colonic human smooth muscle cells (HSMCs) from lipopolysaccharide (LPS)-induced myogenic damage. MATERIALS AND METHODS: LGG was grown in de Man, Rogosa, Share medium at 37°C and samples were collected in middle and late exponential, stationary, and overnight phases. Supernatants were recovered by centrifugation, filtered, and stored at -20°C. The primary HSMCs culture was exposed for 24 hours to purified LPS of a pathogen strain of Escherichia coli (O111:B4) (1 µg/mL) with and without supernatants. Postbiotic effects were evaluated on the basis of HSMCs morphofunctional alterations and interleukin-6 (IL-6) production. Data are expressed as mean±SE (P<0.05 significant). RESULTS: LPS induced persistent, significant, 20.5%±0.7% cell shortening and 34.5%±2.2% decrease in acetylcholine-induced contraction of human HSMCs. These morphofunctional alterations were paralleled to a 365.65%±203.13% increase in IL-6 production. All these effects were dose-dependently reduced by LGG supernatants. Supernatants of the middle exponential phase already partially restored LPS-induced cell shortening by 57.34%±12.7% and IL-6 increase by 145.8%±4.3% but had no effect on LPS-induced inhibition of contraction. Maximal protective effects were obtained with supernatants of the late stationary phase with LPS-induced cell shortening restored by 84.1%±4.7%, inhibition of contraction by 85.5%±6.4%, and IL-6 basal production by 92.7%±1.2%. CONCLUSIONS: LGG-derived products are able to protect human SMCs from LPS-induced myogenic damage. Novel insights have been provided for the possibility that LGG-derived products could reduce the risk of progression to postinfective motor disorders.

Outpatient treatment for liposarcoma of the spermatic cord.

Liposarcoma of the spermatic cord is a very rare neoplastic disease. In effect little more than two hundred cases are described in literature. Natural history of this tumour is characterized by high local recurrence rate although hematogenic and lymphatic spread is usually a late event and involves high-grade tumours. The clinical diagnosis of spermatic cord liposarcoma can be difficult particularly for non expert surgeons, and is often mistaken for different diagnoses. Radical orchiectomy with high cord ligation is the treatment of choice to prevent local recurrence. Otherwise than commonly advised, the treatment is suitable to be performed under local anaesthesia and the patient easily and safely discharged few hours after surgery.

Modified PADSS (Post Anaesthetic Discharge Scoring System) for monitoring outpatients discharge.

The decision to discharge a patient undergoing day surgery is a major step in the hospitalization pathway, because it must be achieved without compromising the quality of care, thus ensuring the same assistance and wellbeing as for a long-term stay. Therefore, the use of an objective assessment for the management of a fair and safe discharge is essential. The authors propose the Post Anaesthetic Discharge Scoring System (PADSS), which considers six criteria: vital signs, ambulation, nausea/vomiting, pain, bleeding and voiding. Each criterion is given a score ranging from 0 to 2. Only patients who achieve a score of 9 or more are considered ready for discharge. Furthermore, PADSS has been modified to ensure a higher level of safety, thus the "vital signs" criteria must never score lower than 2, and none of the other five criteria must ever be equal to 0, even if the total score reaches 9. The effectiveness of PADSS was analyzed on 2432 patients, by recording the incidence of postoperative complications and the readmission to hospital. So far PADDS has proved to be an efficient system that guarantees safe discharge.

NADPH oxidase-mediated platelet isoprostane over-production in cirrhotic patients: implication for platelet activation.

BACKGROUND: In patients with cirrhosis conflicting findings, inherent to platelet function and its clinical implication, are still matters of discussion. Cirrhosis is characterized by enhanced production of isoprostanes, index of oxidative stress in vivo, that is known to stem from nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2)-generating oxidative stress and elicit platelet activation. AIM: To analyse the relationship between oxidative stress and platelet activation in cirrhosis. METHODS: A cross-sectional study including 51 cirrhotic patients and sex- and age-matched control patients has been designed. Soluble NOX2-derived peptide (sNOX2-dp), a direct marker of NADPH oxidase activation, isoprostanes urinary excretion, platelet isoprostanes and two markers of in vivo platelet activation, i.e. soluble CD40 Ligand (sCD40L) and soluble P-selectin (sPs), were measured. RESULTS: Compared with controls, cirrhotic patients had higher levels of sPs (P = 0.034), sCD40L (P < 0.0001), sNOX2-dp (P = 0.0016), urinary excretion of isoprostanes (P < 0.0001) and arachidonic acid-induced platelet isoprostane formation (P < 0.0001). A significant correlation between sNOX2-dp and platelet (R(s) = 0.39, P = 0.0051) and urinary (R(s) = 0.67, P < 0.0001) isoprostanes was detected; also, sNOX2-dp and isoprostanes significantly correlated with sPs and sCD40L. A stepwise regression analysis revealed that sNOX2-dp was independently related to sCD40L plasma levels. CONCLUSIONS: This study provides evidence that in cirrhosis, platelet isoprostanes are over-produced and could be implicated in platelet activation.

[Carotid endarterectomy: evaluation of a "combined" technique of general anesthesia]. / Endoarterectomia carotidea: valutazione di una tecnica di anestesia generale "combinata".

INTRODUCTION: The literature suggests several techniques to ensure the optimal anesthetic procedure for carotid surgery. The aim of our study is to combine, in the carotid endarterectomy, a model of general anesthesia with the loco-regional anesthesia in order to test the safety of the method, the eventual brain damage and hemodynamic stability. We also wanted to test whether the immediate postoperative analgesia was adequate. MATERIAL AND METHODS: Seventy eight (78) patients were enrolled in the study (from 60 to 75 years), ASA II-III, candidates for unilateral carotid endarterectomy in a period from June 2008 to January 2009. During the procedure data about perioperative neurologic and hemodynamic complications were collected. At the end of the surgical treatment the pain at the awakening moment through verbal numerical scale VNS was estimated. Data are presented as mean values +/- sd and validated using the chi2 test, when required. Significance was accepted at a value of P < or = 0.05. RESULTS: 85% of patients reported a VNS between 1 and 2 and 10% equal to 3-5. In the study 95% of patients (P<0.05) appreciated the technique and only 3 patients reported their dissatisfaction. There was no mortality and in 5 patients a postoperative morbidity was registered. DISCUSSION: The study demonstrated the advantages in combining loco-regional anesthesia (valid monitoring of neurological and hemodynamic stability) with general anesthesia (complete airways control and patient comfort) during carotid surgery.

[Two strategies of morphine administration on the control of post-surgical pain after anesthesia with remifentanil]. / Due strategie di somministrazione della morfina per il controllo del dolore post-chirurgico dopo anestesia con remifentanil.

AIM: The post-operative pain (POP) is accompanied by autonomic, psychological and behavioural responses which can result in a significant increase in morbidity and mortality. The purpose of this study was to compare the efficacy and safety of intravenous bolus administration of morphine versus subcutaneous administration. MATERIAL OF STUDY: Fifty subjects scheduled for elective abdominal surgery were randomized into a group S (n = 26) and group E (n = 24). The first group was administered morphine (0.35 mg/kg) subcutaneously immediately after induction of anesthesia, while the second group the same drug at a dose of 0.25 mg/kg was administered intravenously 45' before the end of the intervention. All patients received intraoperative remifentanil (0.25-0.50 microg/kg/min), and at the end of surgery paracetameolo 1 g and ondansetron 4 mg. Upon awakening, the DPO has been reviewed by the NRS (numerical scale of pain) at time zero (TO), after 30' (t1), 1h (T2) and 24h (T3). Furthermore, it was annotated request for rescue doses of morphine and the collateral effects. RESULTS: The two study groups did not show significant differences related to the anthropometric characteristics, duration of surgery, type of surgery, ASA class. No difference between the two groups was highlighted during the evaluation of POP through NRS scale and quantity of "rescue" doses requested. In group E there was a single case of respiratory depression. CONCLUSIONS: Our study suggests that whether intravenous or subcutaneous administration of morphine, both simple and economical analgesic techniques, they are able to guarantee the same quality control of POP in patients undergoing abdominal surgery.

Increased HMGB1 expression and release by mononuclear cells following surgical/anesthesia trauma.

INTRODUCTION: High mobility group box 1 (HMGB1) is a key mediator of inflammation that is actively secreted by macrophages and/or passively released from damaged cells. The proinflammatory role of HMGB1 has been demonstrated in both animal models and humans, since the severity of inflammatory response is strictly related to serum HMGB1 levels in patients suffering from traumatic insult, including operative trauma. This study was undertaken to investigate HMGB1 production kinetics in patients undergoing major elective surgery and to address how circulating mononuclear cells are implicated in this setting. Moreover, we explored the possible relationship between HMGB1 and the proinflammatory cytokine interleukin-6 (IL-6). METHODS: Forty-seven subjects, American Society of Anesthesiologists physical status I and II, scheduled for major abdominal procedures, were enrolled. After intravenous medication with midazolam (0.025 mg/Kg), all patients received a standard general anesthesia protocol, by thiopentone sodium (5 mg/Kg) and fentanyl (1.4 µg/Kg), plus injected Vecuronium (0.08 mg/Kg). Venous peripheral blood was drawn from patients at three different times, t(0): before surgery, t(1): immediately after surgical procedure; t(2): at 24 hours following intervention. Monocytes were purified by incubation with anti-CD14-coated microbeads, followed by sorting with a magnetic device. Cellular localization of HMGB1 was investigated by flow cytometry assay; HMGB1 release in the serum by Western blot. Serum samples were tested for IL-6 levels by ELISA. A one-way repeated-measures analysis ANOVA was performed to assess differences in HMGB1 concentration over time, in monocytes and serum. RESULTS: We show that: a) cellular expression of HMGB1 in monocytes at t(1) was significantly higher as compared to t(0); b) at t(2), a significant increase of HMGB1 levels was found in the sera of patients. Such an increase was concomitant to a significant down-regulation of cellular HMGB1, suggesting that the release of HMGB1 might partially derive from mononuclear cells; c) treatment of monocytes with HMGB1 induced in vitro the release of IL-6; d) at t(2), high amounts of circulating IL-6 were detected as compared to t(0). CONCLUSIONS: This study demonstrates for the first time that surgical/anesthesia trauma is able to induce an early intracellular upregulation of HMGB1 in monocytes of surgical patients, suggesting that HMGB1 derives, at least partially, from monocytes.

[Acute pulmonary oedema associated with laryngospasm after thyroidectomy: a case report]. / Laringospasmo complicato da edema polmonare acuto: caso clinico post-tiroidectomia.

In this paper, a case report of acute pulmonary oedema following thyroidectomy in a 51-year-old male patient is reported. The aetiological factor was vigorous inspiratory effort against an obstruction of the upper airway occurring immediately after extubation. The patient was transferred to intensive care unit and treated with CPAP ventilation. He recovered completely after 48 hours. The pathogenesis of both laryngospasm and an unexpexted but potentially serious complication such as negative-pressure pulmonary oedema is discussed.

Hypotensive anesthesia with propofol and remifentanil: protective effect of alpha-tocopherol on renal function.

STUDY OBJECTIVE: To determine the effect of alpha-tocopherol in patients receiving hypotensive anesthesia with propofol-remifentanil. STUDY DESIGN: Prospective, randomized study. SETTING: University hospital. PATIENTS: 66 ASA physical status I and II patients, aged 32 to 56 years, scheduled for nasal polypectomy. INTERVENTIONS: Patients were allocated into two groups, the treatment and the control groups (T group and C group). T group received alpha-tocopherol 300 mg orally 5 to 6 hours before surgery. MEASUREMENTS: Sampling times and measurements were done before hypotension (t0), 45 minutes after starting hypotension (t1), 90 minutes after starting hypotension (t2), 45 minutes after recovery of normotension (t3), and 24 hours after surgery (t4). Renal function was assessed by testing glomerular and tubular functions: glomerular filtration rate, fractional excretion of sodium (FENA); fractional excretion of urea (FEUN); and urinary N-acetyl-1-beta-D-glucosoaminidase (NAG) index (NAGi). MAIN RESULTS: Glomerular filtration rate values remained unchanged in all patient populations. Fractional excretion of sodium was within reference ranges in both groups at times t0, t1, and t2. At time t3, a significant FE(NA) peak was observed. At this time, FENA was significantly higher in C group than T group (P < 0.001). FEUN time course was similar to the FENA trend. At time t4, FENA and FEUN returned to basal values. At time t3, NAGi was also increased without significant intergroup differences (P < 0.01, P < 0.001, and P < 0.01 vs times t0, t1, t2 in C group, respectively; P < 0.01, P < 0.01, and P < 0.001 vs times t0, t1, and t2 in T group, respectively). CONCLUSIONS: In patients without any renal disease, hypotensive anesthesia with propofol and remifentanil results in a transient tubular dysfunction, which appears to be minimized by the preoperative administration of alpha-tocopherol.

[Postoperative metabolic acidosis: use of three different fluid therapy models]. / L'acidosi metabolica postoperatoria: impiego di tre differenti modeli di fluido-terapia.

Intraoperative fluid administration is considered an important factor in the management of metabolic acidosis following surgical procedures. The aim of this study was to compare three types of intraoperative infusional models in order to evaluate their effect on acid-base changes in the immediate postoperative period as calculated by both the Henderson-Hasselbach equation and the Stewart approach. Forty-seven patients undergoing left hemicolectomy were enrolled in the study and assigned randomly to receiving 0.9% saline alone (Group A, n=16), lactated Ringer's solution alone (Group B, n=16) or 0.9% saline and Ringer's solution, 1:1 ratio (Group C, n=15). Arterial blood samples were taken before operation (t0) and 30 min after extubation (t1) in order to measure the acid-base balance. The results showed a metabolic acidosis status in Group A patients, whereas Group B exhibited metabolic alkalosis only by means of the Stewart method. No difference was found in Group C between the time points t0 and t1 when using either the Henderson-Hasselbach equation or using the Stewart model. We conclude that saline solution in association with Ringer's solution (1:1 ratio) appears to be the most suitable form of intraoperative fluid management in order to guarantee a stable acid-base balance in selected surgical patients during the immediate postoperative period.