Pregabalin effect on acute and chronic pain after cardiac surgery

Introduction. Pain after cardiac surgery affects long-term patient wellness. This study investigated the effect of preoperative pregabalin on acute and chronic pain after elective cardiac surgery with median sternotomy. Methods. Prospective double blind study. 93 cardiac surgery patients were randomly assigned into three groups: Group 1 received placebo, Group 2 received oral pregabalin 75 mg, and Group 3 received oral pregabalin 150 mg. Data were collected 8 hours, 24 hours, and 3 months postoperatively. Results. Patients receiving pregabalin required fewer morphine boluses (10 in controls versus 6 in Group 1 versus 4 in Group 2, p=0.000) and had lower pain scores at 8 hours (4 versus 3 versus 3, p=0.001) and 3 months (3 versus 2 versus 2, p=0.000) and lower morphine consumption at 8 hours (14 versus 13 versus 12 mg, p=0.000) and 24 hours (19.5 versus 16 versus 15 mg, p=0.000). Percentage of patients with sleep disturbances or requiring analgesics was lower in the pregabalin group and even lower with higher pregabalin dose (16/31 versus 5/31 versus 3/31, p=0.000, and 26/31 versus 16/31 versus 10/31, p=0.000, resp.) 3 months after surgery. Conclusion. Preoperative oral pregabalin 75 or 150 mg reduces postoperative morphine requirements and acute and chronic pain after cardiac surgery

Bronchospasm in obese patients undergoing elective laparoscopic surgery under general anesthesia

BACKGROUND: Existing data suggest that obesity correlates with airway hyper-reactivity. However, the incidence of bronchospasm during bariatric surgery in obese patients has not been well studied. METHODS: This was a prospective observational study comparing 50 obese versus 50 non obese patients undergoing elective laparoscopic surgery over a 2 year period. Bronchospasm was detected clinically by auscultation and was confirmed by measuring peak airway pressure during mechanical ventilation. Blood gases were measured at predetermined time intervals intraoperatively. Categorical variables were analyzed using Fisher’s exact test, while numerical variables within and between groups were compared using repeated measures general linear model. RESULTS: The incidence of bronchospasm was significantly higher in obese compared to non obese patients (P = 0.027). Peak airway pressures and blood gases differed significantly when comparing non obese patients versus obese patients without bronchospasm versus obese patients with bronchospasm. Hypoventilation resulting in gradual increase of arterial PaCO(2) was noted in all groups during surgery. CONCLUSION: The incidence of bronchospasm is higher in obese patients compared to non obese patients undergoing elective laparoscopic surgery. Airway pressures and blood gas values in obese patients are somewhere between values in non obese patients and values in patients with bronchospasm, thereby implying that obesity is associated with a state where bronchial smooth muscles are not fully relaxed. Consideration of increased airway reactivity in obese patients undergoing laparoscopic surgery is important for improved patient care and uneventful anesthetic course

Prospective study of the impact of hypotension during anesthesia in patient postoperative outcome

Purpose: Although the relationship between preoperative risk factors and outcomes has been extensively studied, the effect of intraoperative hemodynamic changes in patient’s postoperative course has been less well defined. Methods: We designed a prospective observational study with a view to assess the impact of several variables and especially hypotension on postoperative outcome. Patients considered eligible for the study were all >18yrs old, mentally stable patients scheduled for major abdominal surgery with an expected duration of more than two hours. Total Hypotension Time (THT) along with other variables that possibly influence the outcome was analyzed by using multivariate logistic regression analysis in 100 consecutive patients. Results: Total hypotension time was isolated as a factor significantly associated with morbidity, odds ratio 5.1 (1.95-13.35), and significantly prolonged hospital stay odds ratio 4.56 (1.85-10.96). The patients who had prolonged THT presented more complications (50 vs 30) compared with the others, especially from the cardiovascular, pulmonary and gastrointestinal system. In a significant number, these complications led to delayed hospital discharge (36 to the patients with THT vs 17 to the others). Finally, duration of surgery was associated with postoperative complications, odds ratio 3.1 (1.2-8.0). Conclusion: Persistent hypotension during elective major abdominal surgery is a significant risk factor for postoperative complications and may prolong hospitalization and affect outcomes. Anesthetic management aiming at the avoidance of hypotension during major abdominal surgery, as much as possible, may positively affect outcomes.Η γενική κατάσταση της υγείας του ασθενούς τη χρονική στιγμή που προσέρχεται στο Νοσοκομείο και διάφοροι άλλοι περιεγχειρητικοί παράγοντες (πχ: είδος και βαρύτητα επέμβασης) θεωρείται ότι σχετίζονται με την πρόγνωση της περιεγχειρητικής νοσηρότητας και θνητότητας Σκοπό της μελέτης αποτελεί η διακρίβωση του ρόλου της διεγχειρητικής υπότασης επί ορισμένων χαρακτηριστικών έκβασης, όπως ο χρόνος νοσηλείας, και ο αριθμός και η βαρύτητα των επιπλοκών. ΥΛΙΚΟ ΚΑΙ ΜΕΘΟΔΟΙ Μελετήσαμε προοπτικά πληθυσμό ασθενών που υποβλήθηκαν σε τακτικές, άνω των δύο ωρών, μέσης και μεγάλης χρονικής διάρκειας επεμβάσεις υπό συνδυασμένη (γενική και επισκληρίδιο) αναισθησία. Η περίοδος παρατήρησης περιορίστηκε έως την έξοδο του ασθενούς από το Νοσοκομείο. Ο ορισμός της υπότασης ήταν: ή MAP<60mmHg ή MAP<70mmHg και συγχρόνως μέση πίεση κάτω του 30% της βασικής τιμής Ως επιπλοκή ορίστηκε οποιοδήποτε μετεγχειρητικό σύμπτωμα που δεν εμφανιζόταν στην κανονική ζωή του ασθενούς ή/ και παράλληλα δεν μπορούσε να αντιμετωπιστεί παρά μόνο τη χρήση άμεσης ιατρικής βοήθειας. Ο χρόνος νοσηλείας ορίσθηκε ως φυσιολογικός (ως 9 ημέρες) ή παρατεταμένος (πάνω από 9 ημέρες), ενώ οι ασθενείς χωρίσθηκαν ανάλογα με το αν εμφάνιζαν επιπλοκές ή όχι. Οι ασθενείς χωρίσθηκαν επίσης ανάλογα με την ηλικία, σε άνω και κάτω των 65 ετών και με βάση το Charlson Score (λιγότερο ή περισσότερο του 2). Τέλος, οι ασθενείς χωρίσθηκαν σε 2 ομάδες ανάλογα με το χρόνο διάρκειας του χειρουργείου, 120-180 λεπτά η πρώτη ομάδα, ενώ η δεύτερη με χρόνο διάρκειας πάνω από 180 λεπτά. Η στατιστική ανάλυση έγινε επί 100 ασθενών χρησιμοποιώντας το Pearson chi-square test ή το Fisher’s exact test για άμεσους συσχετισμούς ποιοτικών στοιχείων και τη multivariate logistic regression (binary) για την σύγκριση όλων μαζί των ποιοτικών παραμέτρων. Σε περίπτωση εξέτασης μόνο μιας ποσοτικής μεταβλητής με μια άλλη χρησιμοποιήθηκε η univariate logistic regression ενώ ως επίπεδο σημαντικότητας θεωρήθηκε το P<5%. ΑΠΟΤΕΛΕΣΜΑΤΑ-ΣΥΜΠΕΡΑΣΜΑ Οι επιπλοκές που παρατηρήθηκαν ήταν από το έντερο, όπως η απόσχιση του τραύματος, ειλεός, και επιπλοκές πνευμόνων, καρδιάς και θάνατος. Αποδείχτηκε ότι ασθενείς οι οποίοι διεγχειρητικά παραμένουν σε υπόταση για χρονικό διάστημα πέραν του συνήθους, έχουν στατιστικά σημαντικά αυξημένο κίνδυνο να παρουσιάσουν αυξημένο χρόνο νοσηλείας και αυξημένη μετεγχειρητική νοσηρότητα και θνητότητα. Οι άλλες παράμετροι που μελετήθηκαν (ηλικία, διάρκεια επέμβασης, προεγχειρητική κατάσταση ασθενούς) δεν έδειξαν στατιστικά σημαντική συσχέτιση με το χρόνο νοσηλείας και τις επιπλοκές. Παίρνοντας υπόψη τα παραπάνω, θεωρούμε ότι η υπόταση και η υποάρδευση που ακολουθεί προκαλεί βλάβες σε σημεία μακρινά σε σχέση με το σημείο τραύματος που έχει γίνει από το χειρουργείο και ιδιαίτερα βλάπτει ευαίσθητα όργανα όπως η καρδιά και το έντερο. Συμπερασματικά, η διεγχειρητική υπόταση είναι σημαντικός παράγοντας κινδύνου για τις μετεγχειρητικές επιπλοκές. Οι αναισθητικές παρεμβάσεις που στοχεύουν στην αποφυγή ή στην κατά το πρωϊμότερο διόρθωση υπότασης μπορούν να ευνοήσουν την έκβαση των ασθενών

Depth of Anesthesia as a Risk Factor for Perioperative Morbidity

Introduction. The prognostic value of age, physical status, and duration of surgery on perioperative course has been extensively studied. However, the impact of deep hypnotic time (time when Bispectral Index values are less than 40) has not been well evaluated. Methods. We designed an observational study to clarify the relative influence of deep hypnotic time (DHT) on outcome. Eligible participants were mentally stable patients over 18 years old scheduled for elective major abdominal surgery. In total, 248 patients enrolled. Data were analyzed using Fisher’s exact test and multiple logistic regression. Results. Five variables (DHT, hypotension, age, comorbidity, and duration of surgery) showed statistically significant association with complications, when examined independently. However, when all variables were examined together in a multiple logistic regression model, age and comorbidity were no longer associated with outcome. DHT, hypotension, and duration of surgery were significant predictors of “complications,” and “hypotension” was a significant predictor of prolonged hospital stay (P<0.001).  Conclusion. Deep hypnotic time emerged as a new factor associated with outcome, and its impact compared to other factors such as age, surgery duration, hypotension, and comorbidity is redefined. Monitoring and managing depth of anesthesia during surgery are important and should be part of careful operation planning

Monitoring of brain oxygen saturation (INVOS) in a protocol to direct blood transfusions during cardiac surgery: a prospective randomized clinical trial

Background: Blood transfusions are common in cardiac surgery, but have been associated with increased morbidity and long-term mortality. Efforts to reduce blood product use during cardiac surgery include fluid restriction to minimize hemodilution, and protocols to guide transfusion decisions. INVOS is a modality that monitors brain tissue oxygen saturation, and could be useful in guiding decisions to transfuse. However, the role of INVOS (brain tissue oxygen saturation) as part of an algorithm to direct blood transfusions during cardiac surgery has not been evaluated. This study was conducted to investigate the value of INVOS as part of a protocol for blood transfusions during cardiac surgery. Methods: Prospective, randomized, blinded clinical trial, on 150 (75 per group) elective cardiac surgery patients. The study was approved by the Institution Ethics committee and all patients gave written informed consent. Data were initially analyzed based on "intention to treat", but subsequently were also analyzed "per protocol". Results: When protocol was strictly followed ("per protocol analysis"), compared to the control group, significantly fewer patients monitored with INVOS received any blood transfusions (46 of 70 patients in INVOS group vs. 55 of 67 patients in the control group, p = 0.029). Similarly, patients monitored with INVOS received significantly fewer units of red blood cell transfusions intraoperatively (0.20 +/- 0.50 vs. 0.52 +/- 0.88, p = 0.008) and overall during hospital stay (1.31 +/- 1.20 vs. 1.82 +/- 1.46, p = 0.024). When data from all patients (including patient with protocol violation) were analyzed together ("intention to treat analysis"), the observed reduction of blood transfusions in the INVOS group was still significant (51 of 75 patients transfused in the INVOS group vs. 63 of 75 patients transfused in the control group, p = 0.021), but the overall number of units transfused per patient did not differ significantly between the groups (1.55 +/- 1.97 vs. 1.84 +/- 1.41, p = 0.288). Conclusions: Our data suggest that INVOS could be a useful tool as part of an algorithm to guide decisions for blood transfusion in cardiac surgery. Additional data from rigorous, well designed studies are needed to further evaluate the role of INVOS in guiding blood transfusions in cardiac surgery, and circumvent the limitations of this study