Difficult mask ventilation in obese patients: analysis of predictive factors.

BACKGROUND: This study aimed to determine the accuracy of commonly used preoperative difficult airway indices as predictors of difficult mask ventilation (DMV) in obese patients (BMI >30 kg/m2). METHODS: In 309 consecutive obese patients undergoing general surgery, the modified Mallampati test, patient's Height/Thyromental distance ratio, Inter-Incisor Distance, Protruding Mandible (PM), history of Obstructive Sleep Apnea and Neck Circumference (NC) were recorded preoperatively. DMV was defined as Grade 3 mask ventilation (MV) by the Han's scale (MV inadequate, unstable or requiring two practitioners). Data are shown as means±SD or number and proportions. Independent DMV predictors were identified by multivariate analysis. The discriminating capacity of the model (ROC curve area) and adjusted weights for the risk factors (odds ratios) were also determined. RESULTS: BMI averaged 42.5±8.3 kg/m2. DMV was reported in 27 out of 309 patients (8.8%; 95%CI 5.6-11.9%). The multivariate analysis retained NC (OR 1.17; P<0.0001), limited PM (1.99; P=0.046) and Mallampati test (OR 2.12; P=0.009) as risk predictors for DMV. Male gender was also included in the final model (OR 1.87; P=0.06) as biologically important variable albeit the borderline statistical significance. The model yielded a good discriminating capacity (ROC curve 0.85). The four parameters were used to create an unweighted prediction score (ROC curve 0.84) with >2 associated factors as the best discriminating point for DMV. CONCLUSION: Obese patients show increased incidence of DMV with respect to the undifferentiated surgical population. Limited PM, Mallampati test and NC are important DMV predictors.

Regional anesthesia for carotid endarterectomy: a comparison between ropivacaine and levobupivacaine.

BACKGROUND: This study compares ropivacaine and levobupivacaine when administered for cervical plexus block. The authors therefore compared the arterial pressure profile and the incidence of hypotension between drugs. METHODS: Forty-eight patients scheduled for carotid artery surgery (American Society of Anesthesiologists [ASA] 2-3) were randomly assigned to receive levobupivacaine or ropivacaine (24 patients each). Neurological status, arterial pressure profile and control of postoperative pain were the main observed parameters. All patients had severe carotid stenosis (>80%) and/or had suffered transient ischemic attacks (TIAs) or preoperative strokes. The same team performed anesthesia and surgery for carotid endarterectomy; the cervical block was performed according to Moore's technique.Arterial pressure, heart rate and S(a)O(2p) were monitored continuously with particular regard to T0 (baseline), T1 (immediately before carotid clamping), T2 (immediately before declamping) and T3 (at the end of the procedure). Hypotension was defined as the fall of arterial systolic pressure 30% below baseline or less than 100 mmHg. RESULTS: Arterial pressure fell significantly in both groups at T1 with respect to T0 (P<0.0001). Levobupivacaine patients showed higher mean arterial pressure on T0 (112+/-12 mmHg versus 103+/-7 mmHg; P<0.05), thus suggesting a more pronounced vasodilator effect, as confirmed by the larger drop of arterial diastolic pressure (P=0.007). An absolute 6% difference of hypotension-related drug was recorded with levobupivacaine (19%) as compared with ropivacaine (13%) (P=0.28). CONCLUSIONS: Levobupivacaine has a greater vasodilatory effect than ropivacaine. Its higher incidence of hypotension, although not statistically significant, suggests ropivacaine as the drug of choice for cervical plexus block.

Decreased fluid volume to reduce organ damage: a new approach to burn shock resuscitation? A preliminary study.

OBJECTIVE: To evaluate the impact of decreased fluid resuscitation on multiple-organ dysfunction after severe burns. This approach was referred to as "permissive hypovolaemia". METHODS: Two cohorts of patients with burns>20% BSA without associated injuries and admitted to ICU within 6 h from the thermal injury were compared. Patients were matched for both age and burn severity. The multiple-organ dysfunction score (MODS) by Marshall was calculated for 10 days after ICU admission. Permissive hypovolaemia was administered by a haemodynamic-oriented approach throughout the first 24-h period. Haemodynamic variables, arterial blood lactates and net fluid balance were obtained throughout the first 48 h. RESULTS: Twenty-four patients were enrolled: twelve of them received the Parkland Formula while twelve were resuscitated according to the permissive hypovolaemic approach. Permissive hypovolaemia allowed for less volume infusion (3.2+/-0.7 ml/kg/% burn versus 4.6+/-0.3 ml/kg/% burn; P<0.001), a reduced positive fluid balance (+7.5+/-5.4 l/day versus +12+/-4.7 l/day; P<0.05) and significantly lesser MODS Score values (P=0.003) than the Parkland Formula. Both haemodynamic variables and arterial blood lactate levels were comparable between the patient cohorts throughout the resuscitation period. CONCLUSIONS: Permissive hypovolaemia seems safe and well tolerated by burn patients. Moreover, it seems effective in reducing multiple-organ dysfunction as induced by oedema fluid accumulation and inadequate O2 tissue utilization.

Myocardial necrosis in ICU patients with acute non-cardiac disease: a prospective study.

OBJECTIVE: To ascertain if, after an episode of hypotension, unnoticed myocardial necrosis could occur in critical care patients with acute non-cardiac illness and to search for signs of cardiac necrosis. DESIGN: A prospective observational study. SETTING: General intensive care unit (ICU) at a tertiary level hospital. PATIENTS: Thirty-one patients in two groups. Group 1 included 19 patients with severe sepsis/septic shock (ACCP/SCCM Consensus Conference). Group 2 included 12 patients with hypovolemic shock. INTERVENTIONS: Biochemical markers of myocardial necrosis (cardiac troponin I (cTnI), creatine kinase (CK), creatine kinase MB mass (CKMB) and myoglobin) were measured at 12 h (T1), 24 h (T2) and 48 h (T3) after enrollment. A standard 12-lead ECG was recorded upon enrollment (T0) and at T2. Anomalous Q-waves or ST segment depression or elevation was considered diagnostic for acute myocardial infarction (AMI). A hypotensive episode (arterial systolic pressure < 90 mmHg at heart rate > 100 bpm) was considered moderate if it lasted 30-60 min or severe if longer than 60 min. MEASUREMENTS AND RESULTS: At T0 none of the patients had AMI on ECG. At T2 a non-Q AMI developed in five patients. Increased levels of troponin I, myoglobin, CK and CKMB were found in 74.2 %, 96.8 %, 74.2 % and 67.7 % of the patients, respectively. Cardiac troponin I increased in 11 out of 19 septic patients and in all hypovolemic patients. There was a significant difference between the groups (p < 0.05). All biochemical markers increased in relationship to the degree of hypotension with cTnI again showing a significant difference. The longer the hypotensive episode was, the greater was the increase (moderate hypotension: median 1.16; quartiles 0.55-3.44 ng/ml, severe hypotension: median 8.53; quartiles 1.1-20.7 ng/ml; p < 0.05). Abnormal levels of cTnI were more frequent in non-survivors than in survivors (p < 0.05). CONCLUSIONS: Hypotension may cause cardiac damage in critically ill patients with acute non-cardiac diseases as shown by abnormal levels of cTnI. It is likely that a high number of these myocardial necroses may go unnoticed on the ECG.

[Report of a case of celiac disease associated with transient erythroblastopenia in pediatric age]. / Descrizione di un caso di malattia celiaca associata ad eritroblastopenia transitoria in età pediatrica.

Authors reports a rare case of association between two pathologies that, even if apparently very different, are both immunologically determined: celiac disease (CD) and transient erythroblastopenia of childhood (TEC). Such an association may be less rare commonly thought and this may be true for other autoimmune diseases, too. Clinical and pathological observations, together with etio-pathogenetic hypotheses, are discussed.

Antithrombin III (ATIII) replacement therapy in patients with sepsis and/or postsurgical complications: a controlled double-blind, randomized, multicenter study.

BACKGROUND: ATIII is decreased in sepsis and/or shock and its baseline value correlates with mortality. The efficacy of ATIII therapy on mortality was assessed in a selected group of patients admitted to the intensive care unit (ICU) in a double-blind, randomized, multicenter study. METHODS: 120 patients admitted to the ICU with an ATIII concentration < 70% were randomized to receive ATIII (total dose 24000 units) or placebo treatment for 5 days; 56 patients had septic shock. RESULTS: ATIII concentrations in the treated group remained constant throughout the treatment period (range 97-102%). The Kaplan-Meier analysis showed no difference in overall survival between the two groups: 50 and 46% for ATIII and placebo, respectively. Septic shock and hemodynamic support were unbalanced in the two groups at admission. Therefore the Cox analysis was carried out after adjusting for these two variables. Treatment with ATIII decreases the risk of death with an odds ratio (OR) of 0.56. Of the covariates analyzed, septic shock and the baseline multiple organ failure score were negatively associated with survival and plasma activity level was positively associated with survival with an OR of 0.97 for each 1% increase in the ATIII plasma concentration at baseline. CONCLUSIONS: The results of ATIII treatment in this population of patients suggests that replacement therapy reduces mortality in the subgroup of septic shock patients only.

Sudden death in a child due to rare endocranial neoformation.

A case of unexpected death in a six-year-old child, who died after a period of non-specific symptoms and clinical signs, is described. The cause of death was a pilocytic astrocytoma of the pontocerebellar angle, rare with regard to location and histology. The authors have reviewed the literature, which was scanty.

[Group A beta-hemolytic streptococcus infection and varicella]. / Infezione da streptococco beta-emolitico di gruppo A e varicella.

The case of a 3-year-old boy affected with varicella associated to acute cellulitis by group A beta-hemolytic streptococci is reported. The causes of hospitalization were: high fever, decline of condition, onset of scarlet exanthema and a severe swelling in the inguinoscrotal area, during varicella. The diagnosis of streptococcal infection was confirmed by positive pharyngeal tampon, scarlet exanthema and following rise of ASLO. Since the association of these two infections is reported in literature more and more frequently, the possible causes and precautionary measures are analysed.

The influence of length of stay in the ICU on power of discrimination of a multipurpose severity score (SAPS). ARCHIDIA.

OBJECTIVE: To assess how the power of discrimination of a multipurpose severity score (Simplified Acute Physiology Score; SAPS) changes in relation to the length of stay (LOS) in the intensive care unit (ICU). DESIGN: In order to compute the SAPS probability, a model derived from logistic regression was developed in a cohort of 8059 patients. Measures of calibration (goodness-of-fit statistics) and discrimination [receiver operating characteristic (ROC) curve and relative area under the curve (AUC)] were adopted in a developmental set (5389 patients) and a validation set (2670 patients), both randomly selected. Once the logit was developed and the model validated, the whole database (8059 patients) was again assembled. To evaluate the accuracy of first-day SAPS probability over time, area under the ROC curve was computed for each of the initial 10 days of ICU care and for day 15. SETTING: 24 Italian ICUs. PATIENTS: A total of 8059 patients out of 10065 consecutive admissions over a period of 3 years (1990-1992) were included in this study. Patients whose SAPS was not correctly compiled (n = 687), patients younger than 18 years (n = 442), and patients whose LOS was less than 24 h (n = 877) were excluded from this analysis. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The logistic model gave good results in terms of calibration and discrimination, both in the developmental set (goodness-of-fit: chi 2 = 9.24, p = 0.32; AUC = 0.79 +/- 0.01) and in the validation set (goodness-of-fit: chi 2 = 8.95, p = 0.537; AUC = 0.78 +/- 0.01). The AUC for the whole database showed a loss in discrimination closely related to LOS: 0.79 +/- 0.01 at a day 1 and 0.59 +/- 0.02 at day 15. CONCLUSION: The logistic model that we developed meets high standards for discrimination and calibration. However, SAPS loses its discriminative power over time; accuracy of prediction is maintained at an acceptable level only in patients who stay in the ICU no longer than 5 days. The stay in the ICU represents a complex variable, which is not predictable, that influences the performance of SAPS on the first day.

Chromosome 22 marker in a child with Duane syndrome and urogenital abnormalities.

The nature and the origin of de novo small marker chromosome found at prenatal diagnosis were determined by fluorescence in situ hybridization (FISH) using chromosome centromere-specific probes and by chromosome in situ suppression (CISS) using chromosome specific libraries. The small marker was characterized as being derived from chromosome 22. The fetus which exhibited a minichromosome had kidney malformations and after birth showed clinical features consistent with the Duane anomaly. One previous case with Duane anomaly and abnormalities of urogenital tract associated to a bisatellitated marker derived from chromosome 22 was reported. These findings indicate that a gene or genes located in the region of chromosome 22pter-->q11 may be associated with the Duane anomaly and the development of the urogenital tract.

[Description of two cases of transient hyperphosphatasemia in infancy and childhood]. / Descrizione di due casi di iperfosfatasemia transitoria dell'infanzia.

The authors describe two cases of benign transient hyperphosphatesamia of infancy. This form is not so frequent in childhood and the following criteria must be present for a correct diagnosis: 1) Patient age of less than 5 years. 2) Variable symptoms. 3) No bone or liver disease noted on physical examination. 4) No other biochemical or laboratory evidence for bone or liver disease. 5) A return to normal serum alkaline phosphatase levels within 4 months with no sequelae. We want underline the uselessness of vitamin D therapy and the importance of a deepened study about biochemical and laboratory parameters in all patients affected by alkaline hyperphosphatesamia, to exclude a possible severe disease.

[Anemia and hepatosplenomegaly: search for the protozoon?]. / Anemia ed epatosplenomegalia: cercare il protozoo?

An eight-months-old infant presenting with anemia, hepatosplenomegaly, hypoalbuminemia and polyclonal hypergammaglobulinemia was finally found to be affected by visceral leishmaniasis, after having suspected oncohaematologic problems. Diagnosis was confirmed by bone marrow aspiration. Complete recovery was achieved with antimonial N-methylglucamine (Glucantim) administered IM.

Technical aspects of oxygen saving devices.

Oxygen economizing devices have been extensively studied, both at rest and during muscular exercise, in an attempt to increase the autonomy of a portable oxygen apparatus. The aim of this study is threefold: first, to suggest a simple method to verify in a simple way the technical accuracy of a demand flow oxygen delivery device; second, to suggest how we can monitor in a simple way the clinical efficacy of an economizer; and third, to remember that we can utilize an oxygen saving device to give a better protection than nasal prongs against the worsening of HbO2 desaturation induced by exercise.

A reservoir nasal cannula improves protection given by oxygen during muscular exercise in COPD.

We verified the utility of an oxygen economizer (Pendant Oxymizer) in assuring greater protection than nasal prongs against worsening of oxyhemoglobin resting desaturation (delta SaO2) induced by muscular exercise in 16 patients (ten with chronic obstructive pulmonary disease [COPD] and six with restrictive pulmonary disease). This worsening was quantified as desaturation surface accumulated within five minutes of exercise and was expressed in arbitrary units (au). Each patient carried out the same exercise three times, in a randomized fashion (breathing air or breathing supplemental oxygen [3 L/min] delivered by either nasal prongs or by oxygen economizer). In patients with obstructive disease, delta SaO2 was reduced from 38 +/- 12.0 au when they were breathing air to 18.1 +/- 11.7 au when breathing oxygen by nasal prongs (p less than 0.001) and to 10.1 +/- 9.5 au when breathing oxygen by economizer (p less than 0.001). In patients with restrictive disease, delta SaO2 was reduced from 35.6 +/- 9.9 au when breathing air to 14.9 +/- 10.2 au breathing oxygen by nasal prongs (p less than 0.01) and to 13.7 +/- 10.3 au breathing oxygen by economizer (p less than 0.01). The difference between breathing by economizer and nasal prongs was significant (paired t-test; p less than 0.01) only in patients with COPD. One explanation could lie in the different values of the respiratory rate, which was significantly greater in patients with restrictive disease (20.7 +/- 1.2 breaths per minute at rest and 25.8 +/- 1.5 with exercise) than in patients with obstructive disease (15.3 +/- 1.2 breaths per minute at rest and 20.8 +/- 1.4 with exercise).

Effect of taurine supplementation on fat and bile acid absorption in patients with cystic fibrosis.

Eleven children with cystic fibrosis (CF) and pancreatic insufficiency were given supplementation with taurine (30-40 mg/kg/day) for 2 months, while taking their usual dosage of enzymatic therapy. One patient dropped out of the study because she developed severe constipation. In the other 10 patients, urinary taurine excretion (88 +/- 30.1 mg/m2s.a./24 h) was similar to that of controls (86.2 +/- 6 mg/m2s.a./24 h) before taurine and increased markedly after supplementation (618.2 +/- 79.97 mg/m2s.a./24 h), indicating efficient intestinal absorption. Their coefficient of fat absorption was 81.2 +/- 2.3% and increased significantly after taurine (91.3 +/- 1.13%; p less than 0.01); the area under the curve of plasma triglyceride postprandial levels (1 +/- 0.1 mg X min/ml) also increased significantly after taurine (1.4 +/- 0.3 mg X min/ml; p less than 0.05), showing values very similar to those of controls. Conversely, no change was observed in the serum postprandial levels of glycocholic acid: the maximum postprandial peak before (1.2 +/- 0.3 mumol/l) and after taurine (1 +/- 0.1 mumol/l) remained significantly lower than in controls (2.4 +/- 0.3 mumol/l); p less than 0.01 and p less than 0.001, respectively. Mean total fecal bile acid (BA) excretion was 10.24 +/- 2.15 mg/kg/day before taurine and 12.8 +/- 4.27 mg/kg/day after taurine (normal pediatric values, 2.91 +/- 1.1 mg/kg/day); however, in the individual patients we found a variable trend, four of them showing a net increase in fecal BA excretion.(ABSTRACT TRUNCATED AT 250 WORDS)

A portable oxygen system corrects hypoxemia without significantly increasing metabolic demands.

Some patients with chronic cor pulmonale have hypoxemia only during normal daily activity. This can be corrected by portable oxygen. Whether or not the weight of the apparatus (4.2 kg) adds an additional metabolic demand of sufficient magnitude to cancel or outweigh the advantages of portable oxygen is the subject of this report in 6 patients with chronic obstructive pulmonary disease and 2 with kyphoscoliosis. All received standardized treadmill exercise while breathing room air, and the same exercise with a portable liquid oxygen system sitting on the floor or carried by the patients. The additional load created only a 6.7% increase in CO2 production and did not reverse the supplemental oxygen benefit to arterial oxygen saturation under the experimental conditions of the study.

Value of nocturnal monitoring of transcutaneous O2 and CO2 pressures in adults with respiratory failure.

We have evaluated the reliability of the transcutaneous (t.c.) method of measurement of arterial PO2 and PCO2 in adult man. In 33 simultaneous measurements of 9 normals and 12 patients with a wide range of hypoxemia, we found: t.c. PCO2 = 3.62 + 1.29 PaCO2 +/- 7.3 (r = 0.96) and t.c. PO2 = 11.14 + 0.86 PaO2 +/- 9.89 (r = 0.92). Recalculating t.c. PCO2 to 37 degrees C we can obtain: t.c. PCO2 = 2.7 + 0.97 X PaCO2, stating that there is no significant difference between t.c. PCO2 and PaCO2. The t.c. apparatus detects 10 and 90% O2 pressure changes with a delay of time of about 15 s and 1 min, respectively; the t.c. method is therefore not suitable for detecting changes in PaO2 caused by sleep apnea of short duration. On the contrary the t.c. method provided a useful monitoring of arterial PO2 and PCO2 changes during the night in chronic obstructive pulmonary disease (COPD) and non-COPD patients. A nocturnal monitoring of t.c. PO2 and PCO2 seems: (a) absolutely necessary in non-COPD hypoxemics, especially if total lung capacity (TLC) and/or residual volume (RV) are significantly reduced; (b) not absolutely necessary in COPD hypoxemics, provided they have an enlarged TLC and/or a very expanded RV; (c) advisable in intermediate situations, e.g., in COPD hypoxemics with an associated restrictive disorder caused by heart failure, congestion of pulmonary bed, parenchymal or rib cage disease, in order to establish the optimal concentration of oxygen for each patient and to avoid severe nocturnal hypoxemia without producing a dangerous rise in PaCO2.