The power of mechanical ventilation may predict mortality in critically ill patients.

BACKGROUND: Mechanical power (MP) is the amount of energy transferred from the ventilator to the patient within a unit of time. It has been emphasized in ventilation-induced lung injury (VILI) and mortality. However, its measurement and use in clinical practice are challenging. "Electronic recording systems (ERS)" using mechanical ventilation parameters provided by the ventilator can be helpful to measure and record the MP. The MP (J/minutes) formula is 0.098 x tidal volume x respiratory rate x (Ppeak - ½ ∆P), in which ∆P is the driving pressure and Ppeak is the peak pressure. We aimed to define the association between MP values and ICU mortality, mechanical ventilation days, and intensive care unit length of stay (ICU-LOS). The secondary outcome was to determine the most potent or essential component of power in the equation that has a role in mortality. METHODS: This retrospective study was performed in two centers (VKV American Hospital and Bakirköy Sadi Konuk Hospital ICUs) that used ERS (Metavision IMDsoft) between 2014 and 2018. We uploaded the power formula (MP (J/minutes)=0.098×VT×RR×(Ppeak - ½ ∆P) to ERS (METAvision, iMDsoft, and Consult Orion Health) and calculated the MP value by using MV parameters automatically sent from the ventilator. (∆P; driving pressure, VT; tidal volume, RR; respiratory rate and Ppeak; peak pressure). RESULTS: A total of 3042 patients were included in the study. The median value of MP was 11.3 J/min. Mortality in MP<11.3 J/min was 35.4%, and 49.1% in MP>11.3J/min.; P<0.001. Mechanical ventilation days and ICU-LOS were also statistically longer in the MVP>11.3 J/min group. CONCLUSIONS: The first 24 h MP maybe a predictive value for the ICU patients' prognosis. This implies that MP may be used as a decision-making system to define the clinical approach and as a scoring system to predict patient prognosis.

The association between Acinetobacter baumannii infections and the COVID-19 pandemic in an intensive care unit.

We aimed to describe the increased rate of Acinetobacter baumannii infections during the COVID-19 pandemic and define its significance within the last five years. This study was performed in a tertiary hospital with 280 beds and included all patients infected with A. baumannii in the intensive care unit between January 1, 2018, and June 30, 2022. A. baumannii-infected patients in the intensive care unit 27 months before the pandemic and 27 months during the pandemic were included. Pulsed-field gel electrophoresis was performed to assess clonal relatedness. The infection control measures were specified based on the findings and targeted elimination. In total, 5718 patients were admitted to the intensive care unit from January 1st, 2018, to June 30th, 2022. A. baumannii infection was detected in 81 patients. Compared to the pre-pandemic era, the rate of A. baumannii infection during the pandemic was 1.90 times higher (OR: 1.90, 95% CI: [1.197, 3.033]). Clonality assessment of multidrug-resistant A. baumannii samples revealed eight clusters with one main cluster comprising 14/27 isolates between 2021 and 2022. The case fatality rate of the pre-pandemic and pandemic era was not different statistically (83.33% vs. 81.48%, p = 0.835). Univariate analysis revealed the association of mechanical ventilation (p = 0.002) and bacterial growth in tracheal aspirate (p = 0.001) with fatality. During the COVID-19 pandemic, potential deficits in infection control measures may lead to persistent nosocomial outbreaks. In this study, the introduction of enhanced and customized infection control measures has resulted in the containment of an A. baumannii outbreak.

Is Poliomyelitis Sequelae A Disadvantage for Recovery from Covid-19 ARDS: A Case Report.

We present a case with acute respiratory distress syndrome due to COVID-19 who had poliomyelitis sequelae. He was hospitalized in the intensive care unit and supported by non-invasive mechanical ventilation for 7 days. IL-6 inhibitor was administered due to cytokine storm. No steroid or sedative agents were administered. Early mobilization was performed in the intensive care unit. One month after discharge, physical examination revealed COVID-19 infection did not cause significant changes in muscle strength and physical performance in this patient with poliomyelitis sequelae. It is important to promote early mobilization in the intensive care unit to prevent post-intensive care syndrome in COVID-19 acute respiratory distress syndrome.

Effects of short-term hyperoxic ventilation on lung, kidney, heart, and liver in a rat model: A biochemical evaluation.

BACKGROUND: Despite studies on the adverse effects of hyperoxia, its use is still recommended by the World Health Organization. The aim of this study was to test the possible harmful effects of hyperoxia on the lung, kidney, heart, and liver in a rat mechanical ventilation model. METHODS: Male Wistar rats were randomly assigned into two groups (n=6/group): Normoxic (FiO2: 0.3) or hyperoxic (FiO2: 1.0) ventilation for 4 h. The injury was evaluated in bronchoalveolar lavage (BAL), blood, lung, liver, kidney, and heart was evaluated in terms of cell surface integrity, extracellular matrix (sialic acid, syndecan-1), osmotic stress (free hemoglobin), and redox homeostasis-lipid peroxidaation (malondialdehyde). BAL and wet/dry weight ratio were also evaluated for cellular permeability. RESULTS: Four hours of hyperoxic ventilation did not lead to significant changes in (1) sialic acid, syndecan-1, (2) malondialdehyde levels and wet/dry weight ratio in liver, kidney, heart, and lung compared to normoxic ventilation. CONCLUSION: Mechanical ventilation with hyperoxia seems to have almost similar effects compared to ventilation with normoxia. However, the long term effect of hyperoxia should be evaluated.

Physical rehabilitation in Intensive Care Unit in acute respiratory distress syndrome patients with COVID-19.

BACKGROUND: The risk of muscle weakness is high in the survivors of acute respiratory distress syndrome with COVID-19 following discharge from intensive care unit. AIM: To evaluate the effects of early rehabilitation program in intensive care unit in patients with acute respiratory distress syndrome secondary to COVID-19. DESIGN: The design of the study is observational. SETTING: The setting of the study is inpatient. POPULATION: Thirty-five patients with acute respiratory distress syndrome secondary to COVID-19 were enrolled. METHODS: This study was performed in an intensive care unit of a university hospital. Early rehabilitation program consisting of passive or active range of motion exercises and neuromuscular electrical stimulation in addition to standard intensive care (N.=18) compared to standard intensive care (N.=17). Primary outcome was hand grip strength following discharge. RESULTS: Rehab group had higher prevalence of chronic pulmonary diseases and neurologic diseases. There was no difference in hand grip or manual muscle strength following discharge between rehab and non-rehab groups. No adverse event was noted. CONCLUSIONS: The results did not support the beneficial effects of early rehabilitation in intensive care unit on improving muscle strength. More patients with pulmonary and neurologic diseases in rehab group might impede the impact of rehabilitation on outcomes. On the other hand, these comorbidities underline the role and need of rehabilitation. It is safe both for the patients and the health care workers when necessary precautions are taken. CLINICAL REHABILITATION IMPACT: This study guide how to rehabilitate patients with acute respiratory distress syndrome with COVID-19 during intensive care unit in a safe way.

Appropriate use of tocilizumab in COVID-19 infection.

OBJECTIVE: This study aimed to describe the effectiveness and optimum use of tocilizumab (TCZ) treatment by the support of clinical, laboratory and radiologic observations. METHODS: All patients were followed up in the hospital with daily interleukin-6 (IL-6), C-reactive protein (CRP), ferritin, d-dimer, full blood count, and procalcitonin. Thoracic computed tomography (CT) was performed on admission, when oxygen support was necessary, and seven days after TCZ started. Disease course of the patients was grouped as severe or critical, according to their clinical, laboratory and radiologic evaluations. RESULTS: Forty-three patients were included: 70% were male; the median age was 64 years (minimum-maximum: 27-94); and six (14%) patients died. The median duration of oxygen support before the onset of TCZ was shorter among the severe patient group than the critical patient group (1 vs. 4 days, p < 0.001). Three cases of 21 (14%) who received TCZ in the ward were transferred to ICU, and none of them died. The levels of IL-6, CRP, ferritin, d-dimer, and procalcitonin were significantly lower in the severe cases group than the critical cases group (p = 0.025, p = 0.002, p = 0.008, p = 0.002, and p = 0.001, respectively). Radiological improvement was observed in severe cases on the seventh day of TCZ. Secondary bacterial infection was detected in 41% of critical cases, but none of the severe ones. CONCLUSION: Earlier use of TCZ in COVID-19 infection was beneficial for survival, length of hospitalization and duration of oxygen support. The recommendation for administration of TCZ was based on an increase in requirement of oxygen support, progression in thoracic CT, and elevation of inflammation markers, including IL-6, CRP, ferritin, and d-dimer, and decrease in % lymphocytes.

The frequency, risk factors, and complications of gastrointestinal dysfunction during enteral nutrition in critically ill patients.

BACKGROUND: Gastrointestinal (GI) motility disorders in intensive care patients remain relatively unexplored. Nowadays, the frequency, risk factors and complications of GI dysfunction during enteral nutrition (EN) become more questionable. AIM: To evaluate the frequency, risk factors and complications of GI dysfunction during EN in the first 2 weeks of the intensive care unit (ICU) stay and to identify precautions to prevent the development of GI dysfunction and avoid complications. METHODS: In this prospective observational study, we deliberately targeted at-risk patients. A total of 137 patients who received nasogastric tube feeding in an ICU of a tertiary hospital were enrolled. RESULTS: The incidence of GI dysfunction that was found to be 63% which was associated mainly between MDR bacteria positivity and negative fluid balance. Diarrhea was observed in 36 patients (26%) and on 147 patient-days (incidence rate, 5.5 per 100 patient-days). The median day of diarrhea onset was 6 days after the initiation of EN. Forty patients (29%) presented with constipation (85% during the first week). Fifty patients (36%) exhibited upper digestive intolerance on 212 patient-days (incidence rate, 7.9 per 100 patient-days), after a median EN duration of 6 days (range, 2-14 days). Logistic regression analysis revealed MDR bacteria growth in the culture (OR, 1.75; 95% CI, 1.15-2.67; P=0.008) and negative fluid balance (OR, 0.57; 95% CI, 0.34-0.94; P=0.03) as the risk factors for GI dysfunction. We also showed that GI dysfunction was associated with high SOFA score, hypoalbuminemia, catecholamine use, and prolonged length of stay (LOS). GI dysfunction, on the other hand, can cause some complications including inadequate nutrition, and newly developed decubitus ulcers. CONCLUSION: GI dysfunction should be considered a clinical predictor of inadequate nutrition and prolonged LOS. In addition, the most dramatic risk for GI dysfunction was observed in patients with MDR bacteria growth in the culture and patients in negative fluid balance. Intensivists provide appropriate nutrition for patients, as well as prompt intervention and the development of treatment strategies in the event of GI dysfunction.

Neuroprotective effects of intravenous immunoglobulin are mediated through inhibition of complement activation and apoptosis in a rat model of sepsis.

BACKGROUND: Intravenous (IV) immunoglobulin (Ig) treatment is known to alleviate behavioral deficits and increase survival in the experimentally induced model of sepsis. To delineate the mechanisms by which IVIg treatment prevents neuronal dysfunction, an array of immunological and apoptosis markers was investigated. METHODS: Sepsis was induced by cecal ligation perforation (CLP) in rats. The animals were divided into five groups: sham, control, CLP + saline, CLP + immunoglobulin G (IgG) (250 mg/kg, iv), and CLP + immunoglobulins enriched with immunoglobulin M (IgGAM) (250 mg/kg, iv). Blood and brain samples were taken in two sets of experiments to see the early (24 h) and late (10 days) effects of treatment. Total complement activity, complement 3 (C3), and soluble complement C5b-9 levels were measured in the sera of rats using ELISA-based methods. Cerebral complement, complement receptor, NF-κB, Bax, and Bcl-2 expressions were analyzed by western blot and/or RT-PCR methods. Immune cell infiltration and gliosis were examined by immunohistochemistry using CD3, CD4, CD8, CD11b, CD19, and glial fibrillary acidic protein antibodies. Apoptotic neuronal death was investigated by TUNEL staining. RESULTS: IVIgG and IgGAM administration significantly reduced systemic complement activity and cerebral C5a and C5a receptor expression. Likewise, both treatment methods reduced proapoptotic NF-κB and Bax expressions in the brain. IVIgG and IgGAM treatment induced considerable amelioration in glial cell proliferation and neuronal apoptosis which were increased in non-treated septic rats. CONCLUSIONS: We suggest that IVIgG and IgGAM administration ameliorates neuronal dysfunction and behavioral deficits by reducing apoptotic cell death and glial cell proliferation. In both treatment methods, these beneficial effects might be mediated through reduction of anaphylatoxic C5a activity and subsequent inhibition of inflammation and apoptosis pathways.

A Case of Biotinidase Deficiency in an Adult with Respiratory Failure in the Intensive Care Unit.

BACKGROUND: Biotinidase deficiency (BD) is a rare, inherited autosomal recessive disorder that is treatable within childhood. We present a patient with pneumonia and respiratory acidosis who was not diagnosed with any systemic disorders; the patient was finally diagnosed as BD. CASE REPORT: A thirty-year-old woman was admitted to the emergency department with respiratory failure that had persisted for a few days and progressively weakening over the previous six months. Then, the patient was admitted to the intensive care unit with marked respiratory acidosis, respiratory failure and alterations in consciousness. At the follow-up, the patient was not diagnosed with a systematic disorder. Rather, the patient's historical clinical findings suggested a metabolic disorder. Finally, the patient was diagnosed with biotinidase deficiency. CONCLUSION: Even though biotinidase deficiency is not frequently seen in the intensive care unit, metabolic syndromes such as biotinidase deficiency should be considered. Patients should be evaluated holistically with attention to medical history, family history and clinical findings.

Effects of different recruitment maneuvers on bacterial translocation and ventilator- induced lung injury.

BACKGROUND: Investigated in the present study were the effects of various recruitment maneuvers (RMs) using the same inflation pressure-time product on bacterial translocation from lung to blood, and ventilator-induced lung injury (VILI). METHODS: Tracheotomy was performed on anesthetized rats, and ventilation was initiated using pressure-controlled mode. Subsequently, Pseudomonas aeruginosa was inoculated through the tracheotomy tube and ventilated for 30 minutes before rats were randomly separated into 4 groups. Group 1 underwent sustained inflation (SI), Group 2 underwent low-pressure SI, Group 3 underwent modified sigh, and Group 4 was a control group. Blood cultures were taken at baseline, 15 minutes after randomization (after each RM for the first hour), and finally at 75 minutes after the last RM. The rats were euthanized and the lungs were extirpated. The left lung was taken for measurement of wet:dry weight ratio, and the right lung was used for pathologic evaluation. RESULTS: Positive blood cultures were found to be higher in Group 3 at early study periods. Total pathological scores were also higher in Group 3. CONCLUSION: Higher severity of ventilator-induced lung injury occurred in the modified sigh group, evidenced by bacterial translocation and results of histopathological evaluation.

Effects of intravenous immunoglobulin therapy on behavior deficits and functions in sepsis model.

BACKGROUND: We aim to demonstrate behavioral alterations in a sepsis model using intravenous (IV) immunoglobulin G (IgG) and immunoglobulins enriched with IgA and IgM (IgGAM). METHODS: We divided 48 Wistar albino rats into five groups: control group, sham-operated group (only antibiotic treatment), cecal ligation and puncture (CLP) group (CLP plus antibiotic treatment), IgG group (250 mg/kg IV IgG) and IgGAM group (250 mg/kg IV IgGAM). Intravenous immunoglobulins were given 5 min after the CLP procedure. Experimental animals put into three behavioral tasks 10, 30 and 60 days after the surgery; to evaluate the locomotor activity, an open field test was performed, elevated plus maze test was used to measure anxiety levels, and depressive state was assessed by forced swimming test. The effects of therapy which were acquired from the results of these tests were used to estimate the behavioral changes after CLP. RESULTS: The mortality rate of 50% in the septic rats decreased to 30 and 20% with the administration of IgG and IgGAM, respectively. Significant changes on locomotor activity and depressive-like behavior were reported in the sepsis group; on the other hand, the treatment with immunoglobulins reduced the symptoms. Treatment with immunoglobulins attenuated the sepsis-related anxiogenic-like responses. Behavioral alterations returned to normal on day 60 in all groups. CONCLUSIONS: Sepsis caused deterioration on behavioral parameters. Immunoglobulin treatments alleviated the symptoms of functional disturbances and caused early reversal of behavioral deficits in septic animals.

The Comparison of Automatic Tube Compensation (ATC) and T-piece During Weaning.

OBJECTIVE: Automatic Tube Compensation (ATC) is a newly developed mechanical ventilatory support method. The aim of this study was to compare the ATC and the T-piece as a weaning method. METHODS: Patients who were treated in ICU with mechanical ventilation for longer than 24 hours were included in this prospective clinical study. Fifty patients were divided into two groups for weaning, ATC or T-piece group. Patients tolerating 30 minutes spontaneous breathing trial underwent immediate extubation. The following parameters were recorded just before the spontaneous breathing trial and every 5 minutes during the 30 minute period; PEEP, Pplt, Pmean, FiO2, heart rate, systolic blood pressure, diastolic blood pressure, respiratory rate, SaO2, ETCO2. The primary outcome of the study was successful extubation defined as the ability to maintain spontaneous breathing for 48 hours after extubation. RESULTS: The mean duration of weaning were 4.96 days and 7.42 days in the ATC and T-piece groups, respectively (p value 0.022). There were no significant differences between the groups with respect to the hemodynamic parameters, mechanical ventilation and gas exchange parameters. CONCLUSION: In terms of success for weaning, there was no superiority between the ATC and the T-Piece methods for spontaneous breathing and it was concluded that each of the methods can be used for weaning. The ATC group were compared in terms of successful weaning period but have shown no significant periods of time were found to be lower.

The Comparison of Pressure (PSV) and Volume Support Ventilation (VSV) as a 'Weaning' Mode.

OBJECTIVE: The purpose of our study is to compare two different ventilation modes-pressure support ventilation (PSV) and volume support ventilation (VSV)-as the means of weaning. METHODS: Sixty patients were enrolled in our study. Patients were randomized in to two groups. For the PSV group, FiO2 and airway pressure values were adjusted in order to sustain PaCO2: 35-45 mm Hg, pH>7.32, 6-8 mL kg(-1) TV (tidal volume), and saturation >92%. For the VSV group, FiO2, TV, respiration frequency (f), and peak pressure were adjusted to obtain PaCO2: 35-45 mm Hg, pH>7.32, 6-8 mL kg(-1) TV, saturation >92%, and PO2>60 mm Hg. Every morning, spontaneous breathing was tried in those patients. The patients were extubated after 2 hours of T-piece breathing. The patients who failed spontaneous respiration with the T-piece were returned to mechanical ventilation. Assisted ventilation time (ART), mechanical ventilation time (MRT), total T-piece time (TTT), total weaning time (TWT), and sedation need (SN) values were recorded. "T-test" and "Chi-square" methods were used for statistical analysis. RESULTS: In our study, the mean ART was 82.60 hours for the PSV group and 56.03 hours for the VSV group (p<0.041). TWT was 93.30 hours for the PSV group and 56.03 hours for the VSV group (p<0.035). The mean TTT was 7.67 hours for the PSV group and 3.83 hours for the VSV group (p<0.007). Nineteen patients in the PSV group and 9 patients in the VSV group required sedation during the weaning process (p<0.01). CONCLUSION: In the weaning period, VSV seems to be more advantageous than PSV.

Intravenous immunoglobulins prevent the breakdown of the blood-brain barrier in experimentally induced sepsis.

INTERVENTIONS: The effects of immunoglobulin G and immunoglobulins enriched with immunoglobulin A and immunoglobulin M on blood-brain barrier integrity and survival rates in septic rats were comparatively investigated. MEASUREMENTS: Sepsis was induced by cecal ligation and perforation in Sprague-Dawley rats. The animals were divided into the following groups: Sham, cecal ligation and perforation, cecal ligation and perforation plus immunoglobulin G (250 mg/kg, intravenous), and cecal ligation and perforation plus immunoglobulins enriched with immunoglobulin A and immunoglobulin M (250 mg/kg, intravenous). Immunoglobulins were administered 5 mins before cecal ligation and perforation and the animals were observed for behavioral changes for 24 hrs following cecal ligation and perforation. Blood-brain barrier permeability was functionally and structurally evaluated by determining the extravasation of Evans Blue and horseradish peroxidase tracers, respectively. Immunohistochemistry and Western blotting for occludin were performed. MAIN RESULTS: The high mortality rate (34%) noted in the septic rats was decreased to 15% and 3% by immunoglobulin G and immunoglobulins enriched with immunoglobulin A and immunoglobulin M, respectively (p < .01). Both immunoglobulin G and immunoglobulins enriched with immunoglobulin A and immunoglobulin M alleviated the symptoms of sickness behavior in the septic rats, with the animals becoming healthy and active. Increased extravasation of Evans Blue into the brain tissue of the septic rats was markedly decreased with the administration of both immunoglobulin G and immunoglobulins enriched with immunoglobulin A and immunoglobulin M (p < .01). Occludin expression remained essentially unchanged in all groups, including the cecal ligation and perforation group. In the cecal ligation and perforation group, increased luminal and abluminal vesicles containing electron-dense horseradish peroxidase-reaction product were noted in the cytoplasm of endothelial cells located in the hippocampus and the cerebral cortex. Tight junction was ultrastructurally intact, suggesting that the transcellular pathway is responsible for the blood-brain barrier breakdown in sepsis. Following immunoglobulin G or immunoglobulins enriched with immunoglobulin A and immunoglobulin M treatment, no ultrastructural evidence of leaky capillaries in the brain was observed in the septic rats, indicating the blockade of the transcellular pathway by immunoglobulins administration. CONCLUSIONS: Our study suggests that immunoglobulin G and immunoglobulins enriched with immunoglobulin A and immunoglobulin M improve the integrity of the blood-brain barrier and inhibits cecal ligation and perforation-induced symptoms of sickness behavior in rats.

The treatment of acute liver failure with fractionated plasma separation and adsorption system: Experience in 85 applications.

INTRODUCTION: Artificial liver support systems represent a potential useful option for the treatment of liver failure. The outcomes of patients treated with the fractionated plasma separation and adsorption (FPSA) system are presented. PATIENTS AND METHODS: FPSA was performed 85 times for 27 patients (median 3 treatments/patient) with liver failure [85.2% acute liver failure (ALF) and 14.8% acute-on-chronic liver failure] using the Prometheus 4008H (Fresenius Medical Care) unit. Citrate was used for anticoagulation. A variety of clinical and biochemical parameters were assessed. Comparisons between pretreatment and post-treatment data were performed using paired t-test. RESULTS: The 85 sessions had a mean duration of 6 h. There were significant decreases in total bilirubin (13.18 +/- 9.46 mg/dL vs. 9.76 +/- 7.05 mg/dL; P < 0.0001), ammonia (167.6 +/- 75 mg/dL vs. 120 +/- 43.8 mg/dL; P < 0.0001), blood urea nitrogen (BUN; 12.55 +/- 13.03 mg/dL vs. 8.18 +/- 8.15 mg/dL; P < 0.0001), creatinine (0.54 +/- 0.47 mg/dL vs. 0.46 +/- 0.37 mg/dL; P = 0.0022) levels, and in pH (7.48 +/- 0.05 vs. 7.44 +/- 0.08; P = 0.0045). Four patients (14.8%) received liver transplantation after the treatments; in nine patients, transplantation was not necessary anymore (33%); the remaining 14 patients did not receive a transplantation because they were either not appropriate candidates or no organ was available. Overall survival was 48.1% (4 transplanted and 9 treated patients). No hematological complications related to FPSA were observed. CONCLUSIONS: FPSA system is a safe and effective detoxification method for patients with liver dysfunction, including ALF. The system is useful as a symptomatic treatment before liver transplantation; in up to 1/3 of the cases, it can even be used as a sole method of treatment.

[Spinal anesthesia in cesarean section with different combinations of bupivacaine and fentanyl]. / Sezaryen operasyonlarinda farkli fentanil ve bupivakain kombinasyonlari ile spinal anestezi.

The use of opioids for spinal anesthesia increases the anesthetic quality, reduces side effects and also has advantages for the postoperative analgesia. The aim of this study was to evaluate the effects of subarachnoid %0.5 hyperbaric bupivacaine (B) alone or combined with 10 or 20 mg fentanyl (F) on the anesthetic properties for cesarean section and newborn. 45 patients were randomized to three groups to receive 1.8 ml anesthetic drug for spinal anesthesia. GI (n=15) received B, GII (n=15) 10 mg F+B, GIII (n=15) 20 mg F+B. The onset of sensory blok at T4 level, maximum anesthetic level and the onset time, the level of the motor block, duration of effective analgesia, use of total i.v. fluids and ephedrine, relaxation at the operative area, side effects, umblical cord blood gases, Apgar and neurological and adaptive capacity scores of the newborn were compared among the groups. We conclude that compared to control group, the addition of fentanyl to hyperbaric bupivacaine leads to a decrease in local anesthetic doses and so to a decrease in the incidence of side effects and postoperative analgesic consumption. 7 mg B+20 mg F seems to be the preferable combination for that reasons.

Effects of positive end-expiratory pressure on ventilatory and oxygenation parameters during pressure-controlled one-lung ventilation.

OBJECTIVES: The purpose of this study was to investigate the effects of PEEP on oxygenation and airway pressures during PCV-OLV. DESIGN: Randomized, crossover, clinical study. SETTING: University hospital. PARTICIPANTS: Twenty-five patients undergoing thoracotomy. INTERVENTIONS: During the first 5 minutes of OLV, all patients were ventilated with VCV (PEEP: 0) (VCV-ZEEP). Afterward, ventilation was changed to PCV with PEEP: 0 (PCV-ZEEP) or PEEP: 4 cmH2O (PCV-PEEP) for 20 minutes. In the following 20 minutes, PCV-PEEP and PCV-ZEEP were applied in reverse sequence. MEASUREMENTS AND MAIN RESULTS: At the end of VCV-ZEEP airway pressures (peak airway pressure, plateau airway pressure, mean airway pressure, and pause airway pressure) were recorded. At the end of PCV-PEEP and PCV-ZEEP airway pressures, PaO2 and Qs/Qt were recorded. Ppeak and Pplat were significantly lower with PCV-PEEP compared with VCV-ZEEP (eg, Ppeak: 33.4+/-4.2, 28.3+/-4.1, and 28.9+/-3.7 cmH2O in VCV-ZEEP, PCV-ZEEP, and PCV-PEEP, respectively; p<0.05 for PCV-ZEEP v VCV-ZEEP and PCV-PEEP v VCV-ZEEP). PCV-PEEP was associated with an increased PaO2 (230.3+/-69.8 v 189.0+/-54.8 mmHg, p<0.05) and decreased Qs/Qt (33.4%+/-7.3% v 38.4%+/-5.7%, p<0.05) compared with PCV-ZEEP (mean+/-SD). Eighty-eight percent of the patients have benefited from PEEP. CONCLUSION: During OLV, PCV with a low level of PEEP leads to improved oxygenation with lower airway pressures.