Anteia Paraskeva

Postoperative Pain and Analgesic Requirements After Anesthesia with Sevoflurane, Desflurane or Propofol

BACKGROUND: General anesthetics may have nociceptive actions that affect postoperative pain. In studies evaluating postoperative pain, the effect of general anesthetics on analgesic requirements has not been considered except for one recent study suggesting that propofol anesthesia provides better analgesia after surgery than isoflurane. METHODS: In this prospective, blind, randomized trial we recorded postoperative analgesic requirements (mg of morphine) and pain scores (visual analog scale in mm) 2, 4, 8, and 24 h postoperatively in patients undergoing abdominal hysterectomy or myomectomy under sevoflurane, desflurane or propofol anesthesia, titrated to maintain Bispectral Index values between 35 and 45. Pain scores were also recorded immediately after transfer to the postanesthesia care unit. RESULTS: Cumulative morphine consumption did not differ among the three groups 2, 4, 8, or 24 h postoperatively (P = 0.50). The morphine consumed within 24 h postoperatively was 28 ± 13.8 mg in the sevoflurane group, 25 ± 11.7 mg in the desflurane group and 27 ± 16.1 mg in the propofol group. The visual analog scale values at rest or after cough immediately after patient transport to the postanesthesia care unit and 2, 4, 8, and 24 h after surgery did not differ among the three groups (P = 0.40, 0.39, 0.50, 0.47, 0.06 at rest and P = 0.67, 0.45, 0.22, 0.26, 0.29 after cough respectively). CONCLUSION: Morphine consumption and pain 24 h postoperatively did not differ among the sevoflurane, desflurane, and propofol groups.

Perioperative pregabalin for acute and chronic pain after abdominal hysterectomy or myomectomy: a randomised controlled trial.

Context The antiepileptics gabapentin and pregabalin are used as adjuvants to control postoperative pain. Objective The aim of the present study was to investigate the effect of perioperative administration of pregabalin on postoperative acute and chronic pain and analgesic requirements. Setting Department of Anaesthesiology, Aretaieio University Hospital, Athens, Greece. Patients Eighty patients scheduled for abdominal hysterectomy or myomectomy were randomly assigned to the pregabalin or to the control group. Intervention The pregabalin group received 150 mg of pregabalin 8-hourly, starting on the afternoon before surgery and continued until the fifth postoperative day. The control group was similarly treated, but received placebo capsules instead. Measurements Postoperative intravenous morphine and Lonalgal (30 mg codeine with 500 mg paracetamol) tablet consumption, visual analogue pain scores at rest and on coughing, sedation, anxiety, dizziness, ataxia, blurred vision and diplopia were recorded. One and 3 months postoperatively patients were interviewed for the presence of pain and analgesic needs due to surgery. Results The pregabalin-treated patients consumed less morphine during the first 48 h postoperatively (P = 0.0001). However, consumption of Lonalgal tablets and visual analogue scores for pain at rest and on coughing did not differ between the groups. No difference was found in sedation and anxiety scores between the patients who received placebo or pregabalin. Patients in the control group had lower incidences of dizziness (29 versus 58%, P = 0.015), ataxia (0 versus 18%, P = 0.011), blurred vision (6 versus 26%, P = 0.028) and diplopia (0 versus 16%, P = 0.023). Presence of pain, analgesic intake due to surgery and decreased or absent sensation around the wound did not differ between the groups 1 and 3 months postoperatively. Conclusion Pregabalin in the doses given decreased morphine requirements for the first 48 h postoperatively, but neither altered the analgesic requirements beyond 48 h nor had any effect on acute, late or chronic pain.

Acupressure on the Extra 1 Acupoint: The Effect on Bispectral Index, Serum Melatonin, Plasma β-endorphin, and Stress

BACKGROUND: Acupressure on the “extra 1” point decreases bispectral index (BIS) values and stress. METHODS: We investigated the BIS, melatonin, β-endorphin, and verbal stress score values before, after 10 min of acupressure application on the extra 1 point, on a sham point, after no acupressure, and 1 h after completion of each intervention in 12 volunteers. RESULTS: The BIS and verbal stress score values were decreased after acupressure on the extra 1 point (P = 0.0001 and P = 0.008, respectively), but melatonin and β-endorphin did not change. CONCLUSION: Acupressure on the extra 1 point has no effect on melatonin and β-endorphin levels.

Impact of Graded Hypothermia on Coagulation and Fibrinolysis

BACKGROUND Hypothermia has a detrimental effect on hemostatic mechanism. The purpose of this experimental study was to investigate the effect of graded hypothermia on markers of the anticoagulant system (antithrombin III and protein C) and fibrinolytic system (plasminogen, α(2)-antiplasmin), and on vascular wall and other tissue specimens. MATERIALS AND METHODS Ten New Zealand rabbits were subjected to mild and then moderate core hypothermia of 32 °C for 60 min. Blood samples were obtained at normothermic (T(1)), mild (T(2)), and moderate (T(3)) hypothermic conditions. Chromogenic assay methods were used to determine quantitatively (%) the activity of antithrombin III, protein C, plasminogen, and α(2)-antiplasmin. Hypothermic values were compared with the normothermic values. Tissue and vessel wall specimens were examined under light microscope. RESULTS Reduction of activity (%) from normothermia (T(1)) to mild (T(2)) and moderate (T(3)) hypothermia was found for antithrombin III (103.40 ± 12.54, 87.40 ± 13.50, and 82.70 ± 20.78, respectively, with statistically significant difference between T(1)-T(3): P = 0.03), for protein C (70.1 ± 7.51, 56.30 ± 8.34, and 53.1 ± 7.34, with statistically significant difference between T(1)-T(2) and T(1)-T(3): P = 0.015 for both comparisons) and α(2)-antiplasmin (97 ± 9.63, 80.60 ± 11.73, and 83.70 ± 13.94, with statistically significant difference between T(1)-T(2): P = 0.006). Plasminogen activity was increased (14.50 ± 0.52, 16.30 ± 1.63, and 17.30 ± 2.45, with statistically significant difference between T(1)-T(2) and T(1)-T(3): P = 0.033 for both comparisons). Histologic examination revealed no significant lesions on tissue and vessel wall specimens. CONCLUSIONS The results of our study suggest that even though the hypothermia period was relatively short, the processes of coagulation and fibrinolysis were altered with simultaneous changes.

Intravenous lidocaine does not affect the anesthetic depth during rapid sequence induction and intubation as assessed by Bispectral Index monitoring: a randomized double blind study.

Introduction We investigated the impact of intravenous lidocaine on anesthetic depth, as assessed by Bispectral Index score (BIS), and hemodynamic responses to rapid sequence induction/intubation. Material and methods Eighty-four surgical patients with risk factors for regurgitation/aspiration were randomized to receive either lidocaine 1.5 mg/kg or normal saline in a double-blind fashion. Propofol 2 mg/kg, lidocaine or normal saline, followed by rocuronium 1 mg/kg were administered intravenously and trachea was intubated under cricoid pressure application. The BIS scores were recorded before induction of anesthesia, immediately after, at 30 s and 1 min after rocuronium injection and every 30 s after intubation, for 10 min. Systolic/diastolic blood pressure and heart rate were measured before induction, immediately after and at 1 min following rocuronium administration, and every minute for 10 min after intubation. Results Data from 78 patients were analyzed. Demograpic characteristics did not differ between the study groups. A total of 24 BIS scores were recorded for each patient. No difference was found in BIS values between lidocaine and control groups at any time point (F = 2.936, p = 0.91). Also no difference was detected in heart rate, systolic and diastolic blood pressure at any time point of the study period between the two groups (F = 0.063, p = 0.80, F = 0.007, p = 0.93, F = 0.435, p = 0.51 respectively). No episodes of significant bradycardia occurred and none of the patients reported awareness/recall of the procedure. Conclusions Lidocaine 1.5 mg/kg given intravenously during rapid sequence induction does not affect BIS values, or blunt the hemodymanic response to laryngoscopy and intubation.

Postoperative analgesic requirements after subarachnoid or epidural anesthesia with ropivacaine 0.75% in cesarean section. A double-blind randomized trial

Abstract Objective: Postoperative analgesic requirements and pain scores were compared after subarachnoid versus epidural anesthesia with plain ropivacaine 0.75% for elective cesarean section. Study design: Ropivacaine 0.75% was randomly administered for subarachnoid or epidural anesthesia in 108 parturients, scheduled for cesarean section. Times for the sensory block to reach T4 level and to regress to T6 level were recorded. At 2, 4, 8 and 24 h postoperatively, pain scores at rest and cough, morphine consumption as well as patient satisfaction, incidence of headache, nausea and/or vomiting were measured. Results: Median (min–max) time for the sensory block to reach T4 was 7 (3–0) min versus 24 (16–73) min and to regress to T6 was 126 (70–332) min versus 200 (98–439) min in the subarachnoid and epidural groups, respectively (p = 0.001). Although the subarachnoid had more analgesic consumption than the epidural group at 2 and 4 h postoperatively (7.3 ± 4.7 vs. 1.8 ± 2.4 mg, p = 0.001 and 9 ± 5.7 vs. 3.3 ± 3.8 mg, p = 0.001, respectively) no difference was observed at 8 or 24 h postoperatively (p = 0.14 and p = 0.38, respectively). VAS scores at rest and after cough (p = 0.56, p = 0.35, respectively), patient satisfaction (p = 0.61), incidence of headache (p = 1.0), nausea and/or vomiting (p = 0.78) did not differ between the two groups. Conclusions: Postoperative pain, analgesic requirements, patient satisfaction and adverse effects did not differ when subarachnoid or epidural anesthesia with ropivacaine 0.75% was used for elective cesarean section. Nevertheless, subarachnoid provides faster onset and offset of the block, compared to epidural anesthesia. The key limitation of this study is the lack of postoperative serum ropivacaine measurements taken with concurrent pain score measurements.

Ropivacaine spinal anesthesia is not antagonized by ondansetron pretreatment.

BACKGROUND: We investigated a possible effect of ondansetron on the duration of sensory and motor block produced by ropivacaine. METHODS: Fifty male patients undergoing transurethral surgery received either 8 mg oral ondansetron the evening before surgery plus IV 8 mg ondansetron 15 min before subarachnoid anesthesia or placebo. All patients received 2.2 mL of 0.75% plain ropivacaine intrathecally. Sensory and motor block were assessed 30 min after the intrathecal injection and every 30 min thereafter until recovery from the motor block. RESULTS: Thirty minutes after spinal injection of ropivacaine, we first measured, in both groups, the time to maximum block for both sensory and motor modalities. The maximum level of the sensory block, defined as decreased sensation, was T8 in the control and T6 in the ondansetron group, and absence of sensation was defined as T11 and T9 for the control and the ondansetron groups, respectively. Regarding block duration, 180 min after spinal injection, sensory block was detected in 11 of 22 and 16 of 24 patients and motor block in 1 of 22 and 0 of 24 in the control and ondansetron groups, respectively. Sensory and motor block did not differ between groups at any measured time point. CONCLUSIONS: Ondansetron had no effect on the subarachnoid sensory or motor block produced by ropivacaine.

Cesarean delivery under spinal anesthesia is associated with decreases in cerebral oxygen saturation as assessed by NIRS: an observational study

Abstract Objectives: To investigate the effect of spinal anesthesia on cerebral rSO2 during elective cesarean delivery (CD). Methods: Thirty-four women scheduled for elective CD under spinal anesthesia were recruited. In the operating room rSO2 of the left and right frontal area and right thigh was recorded using three disposable sensors. A combination of 1.8–2.0 ml of 0.75% ropivacaine plus 10 μg of fentanyl were injected intrathecally. Systolic and diastolic blood pressure, heart rate, SpO2 as well as rSO2 of the left and right forehead areas and right thigh were recorded before, 5, 10, and 25 to 50 minutes after spinal injection, after uterine incision and placenta delivery, and analyzed with ANOVA repeated measures. The study was approved by the Aretaieio Hospital Institutional Review Board and registered with ClinicalTrials.gov (ID: NCT01669135). Results: The rSO2 left and right frontal area values decreased significantly from baseline (p = 0.0001 and p = 0.0001 respectively), with most remarkable decreases 5 and 10 minutes after spinal injection, from 65 (SD 8.7) % to 56 (SD 9.3) % and 56 (SD 9.5) % (p = 0.0001 and p = 0.0001) for the left and from 63 (SD 7.7) % to 55 (SD 9.3) % and 56 (SD 8.9) % (p = 0,0001 and p = 0.0001) for the right frontal area respectively. The rSO2 right thigh values increased significantly during the study period (p = 0.0001). Key limitations: Contribution of extracranial circulation to the rSO2, lack of PaCO2 and cardiac output measurements. Conclusions: Women undergoing CD under spinal anesthesia may present decreases in cerebral rSO2. The clinical impact of these results remains to be determined. Trial registration: ClinicalTrials.gov identifier: NCT01669135.

An assessment of subarachnoid block: a survey of 175 articles and recommendations for improvement.

BACKGROUND: Assessment of subarachnoid block, particularly the sensory component, may be incomplete and influence the conclusions of studies involving subarachnoid anesthesia, as well as their application in routine clinical practice. METHODS: We manually searched 175 articles concerning subarachnoid block published from 2006 to 2009 in 8 anesthesia journals to determine the components of the subarachnoid anesthetic procedure recorded as well as the extent of sympathetic and motor block. RESULTS: The level of subarachnoid injection was reported in 86% of the articles, baricity in 84%, concentration of local anesthetic in 77%, patients position in 75%, needle size in 77%, and needle type in 71%. The stimulus used for assessing sensory block was reported in 69% of the articles; 17% described the block as unilateral or bilateral, and 11% described the lines along which the stimulus was applied. Motor and sympathetic block were assessed in 40% and 18% of studies, respectively. CONCLUSIONS: These results suggest incomplete description of tools and assessment of sensory block in studies involving subarachnoid anesthesia. We propose a checklist to facilitate a more standardized evaluation of the extent of subarachnoid anesthesia.

Intravenous morphine and droperidol after caesarean delivery under subarachnoid anaesthesia has no effect on postoperative pain or analgesic requirements.

Background and objective Opioids are routinely administered to obtain a better control of postoperative pain. The aim of the present study was to assess the intravenous morphine effect after caesarean delivery on the postoperative morphine requirements and pain. Methods Sixty-two parturients undergoing elective caesarean section under subarachnoid anaesthesia were randomly assigned in a double-blinded manner to the morphine or to the control group, to receive intraoperatively 0.15 mg kg−1 morphine in 100 ml of isotonic saline or equal volume of normal saline. Postoperative analgesia was ensured with patient-controlled analgesia morphine. Postoperative pain at rest and after cough was assessed using the visual analogue scale (VAS) 2, 4, 8, and 24 h. Morphine consumption was recorded at the same time points. Results Cumulative morphine consumption 2, 4, 8, and 24 h postoperatively was 6 ± 4.8, 14 ± 6.6, 22 ± 9.6, and 42 ± 15.7 mg in the morphine and 8 ± 5.1, 18 ± 7.7, 28 ± 9.4, and 43 ± 17.4 mg in the control group (F = 2.70, DF = 1, and P = 0.105 for intergroup comparisons). The VAS scores at rest did not differ between the two groups, being 28 ± 22.3, 40 ± 21.4, 28 ± 18.5, and 28 ± 22.2 mm in the morphine group and 28 ± 21.5, 43 ± 23.5, 29 ± 24.2, and 19 ± 24.8 mm in the controls (F = 0.37, DF = 1, P = 0.848). Similar results apply to the VAS scores recorded after cough. VAS values were 35 ± 20.6, 51 ± 22.5, 42 ± 18.2, and 46 ± 23.6 mm in the morphine and 40 ± 22.1, 54 ± 28.9, 47 ± 26.5, and 38 ± 26.9 mm in the control group, respectively. Conclusion Morphine given after caesarean delivery under subarachnoid anaesthesia has no effect on analgesic requirements or acute postoperative pain.