Assessment of recovery, dreaming, hemodynamics, and satisfaction in postcardiac surgery patients receiving supplementary propofol sedation with S(+)-ketamine

BACKGROUND

S(+)-ketamine is an analgesic and sedative drug with dissociative attributes. When it is used without sedatives, nightmares have been described. The aim of this study was to assess the effects of postoperative analgosedation with propofol and S(+)-ketamine when compared to standard propofol analgosedation in terms of recovery, dreaming, hemodynamics, and patient satisfaction.

METHODS

Forty-eight patients were sedated with propofol (1-3 mg/kg/h) after coronary artery bypass grafting and allocated randomly on admission to the intensive care unit to receive either S(+)ketamine (2 mg mg/kg/h; group A) or 0.9% saline as a placebo (group B) in a double-blind fashion. If necessary, boli of 3.75 mg piritramide (an opioid) were given in both groups.

RESULTS

Patients receiving S(+)-ketamine had significantly higher satisfaction for pain management (Visual Analog Scale [VAS] = group A: median 10 [range 9-10]; group B: median 9 [range 6-10]) despite their lower piritramide consumption. Patients receiving S(+)ketamine showed significantly faster eye opening (82+/-51 vs 156+/-110 min) but dreamed significantly more often (at 2 h, 67% in group A vs 29% in group B; at 24 h, 43% in group A vs 10% in group B), whereas no significant differences were detected in the incidence of nightmares at 2 h, 14% in group A vs 10% in group B; at 24 h, 5% in group A vs 5% in group B.

CONCLUSIONS

Patients receiving S(+)-ketamine showed higher satisfaction for pain management and dreamed more often, but they did not have more nightmares.

RETRACTED: Inspired oxygen fraction of 0.8 compared with 0.4 does not further reduce postoperative nausea and vomiting in dolasetron-treated patients undergoing laparoscopic cholecystectomy

BACKGROUND

Postoperative nausea and vomiting (PONV) is one of the most frequent complications after general anaesthesia. Single-dose antiemetic prophylaxis has limited efficacy in high-risk patients. Adding a simple potential antiemetic approach, such as increasing the inspired oxygen fraction, to the antiemetic portfolio would preserve pharmacological interventions for treatment of symptoms in the postoperative period. However, the antiemetic effect of a high inspired oxygen fraction is still discussed controversially. The aim of the study was to evaluate whether an inspired oxygen fraction of 0.8 decreases PONV in patients receiving the 5-HT3-antagonist dolasetron.

METHODS

In a randomized, placebo-controlled, double-blinded trial we studied 377 patients (ASA I-III) undergoing elective laparoscopic cholecystectomy. Induction of anaesthesia was standardized, including thiopental fentanyl and cis-atracurium. For all patients the individual risk for PONV was calculated using the Koivuranta score and all patients received 12.5 mg dolasetron i.v. before surgery. Patients were allocated randomly to one of three groups: Group A (n=125) received 80% oxygen in air, Group B (n=125) 40% oxygen in air and Group C (n=127) 40% oxygen in nitrous oxide. Postoperative nausea, postoperative vomiting (PV), or nausea, vomiting, or both (PONV) was assessed in the early (0-4 h) and overall postoperative period (0-24 h) by an anaesthesiologist unaware of patient allocation.

RESULTS

There was a significantly lower incidence of PONV and PV in Groups A (PONV: 11.2%; PV: 3.2%) and B (PONV: 10.4%; PV: 3.2%) compared with Group C (PONV: 26.7%; PV: 13.3%), but there were no significant differences between Groups A and B.

CONCLUSIONS

An inspired oxygen fraction of 0.8 does not further decrease PONV or vomiting in dolasetron-treated patients undergoing laparoscopic cholecystectomy. The lower incidence of PONV in Groups A and B compared with Group C is most likely caused by the omission of nitrous oxide.

A comparison of nefopam and clonidine for the prevention of postanaesthetic shivering: a comparative, double-blind and placebo-controlled dose-ranging study

Postanaesthetic shivering is a frequent complication following general anaesthesia. The aim of this study was to compare the effectiveness of three doses of nefopam with clonidine and placebo in the prevention of postanaesthetic shivering. We studied 371 patients undergoing abdominal or orthopaedic surgery. Patients were allocated to one of five groups: Group A (n = 73) received 0.2 mg x kg(-1) nefopam, Group B (n = 75) 0.1 mg x kg(-1) nefopam, Group C (n = 76) 0.05 mg x kg(-1) nefopam, Group D (n = 73) 1.5 microg x kg(-1) clonidine, and Group E (n = 74) saline 0.9% as placebo. We found a significant reduction in the incidence of shivering in Group A compared to Group C and clonidine as well as to the placebo group. All active treatments reduced the incidence and the severity of shivering compared to placebo. At 5 min postoperatively clonidine-treated patients showed a significant decrease in MAP and a significantly lower Aldrete score compared to all other groups. No haemodynamic or sedative adverse events were observed in the nefopam-treated patients. The results of our study indicate that nefopam (0.2 mg x kg(-1)) is superior to clonidine (1.5 microg x kg(-1)) in the prophylaxis of postanaesthetic shivering and not accompanied by sedative or haemodynamic side-effects.

Do we necessarily need local anaesthetics for venous cannulation? A comparison of different cannula sizes

BACKGROUND AND OBJECTIVE

This randomized, prospective study was performed to evaluate the efficacy of a subcutaneous local anaesthetic infiltration prior to venepuncture using different cannula sizes.

METHODS

Three-hundred-and-one patients were included in the study, 150 received mepivacaine 1% (0.25 mL) subcutaneously, 151 were cannulated without local analgesia. Patients were further allocated to one of five cannula size groups (standard wire gauge (G)): 20-, 18-, 17-, 16- and 14-G. They were asked to quantify the pain experienced using a four-point rating scale.

RESULTS

In the group without local anaesthetics, 28.8% complained about pain compared to 12% receiving local analgesia. The incidence of pain for 14-G (10%) and 16-G (12.9%) cannulae was significantly reduced in the local analgesia group (P < 0.01) compared to no local analgesia (77.4% and 45.1%). Other cannula sizes showed no difference in pain whether using local analgesia or not.

CONCLUSIONS

Patients profit from a subcutaneous infiltration with mepivacaine 1% prior to intravenous cathetherization only when cannulae of size > or = 16-G are inserted.

Ein Vergleich der ProSeal®-Larynxmaske mit der konventionellen endotrachealen Intubation bei Laparoskopien in der Gynäkologie

BACKGROUND

The aim of this study was to assess the practicality of the ProSeal laryngeal mask (PS-LMA) airway during laparoscopic surgery with capnoperitoneum compared to endotracheal intubation (ET).

METHODS

Prospective, randomized study. 104 patients undergoing gynaecologic, laparoscopic surgery were allocated randomly to two groups: 1. ET-group (n = 50). 2. PS-LMA-group (n = 54). Total intravenous anaesthesia was performed by the same anaesthesiologist.

MEASUREMENTS

Mean arterial pressure, heart rate, at 4 and circuit pressure at 2 measurement points, and the incidences of coughing and sore throat. Insertion of the ET and the PS-LMA was scored by using a four-point scale. Ease of placing the gastric tube was judged by measuring the number of attempts at insertion and the insertion times. A p-value of < 0.05 was considered as significant.

RESULTS

There were no differences between PS-LMA and ET concerning circuit pressure at any measurement point. At the end of anaesthesia, mean arterial pressure (92 +/- 13 vs. 100 +/- 14 mmHg; p < 0.01) and heart rate (66 +/- 13 vs. 76 +/- 14 beats/min; p < 0.01) were lower in the PS-LMA-group compared to the ET-group. At the end of anaesthesia 25 patients of the ET-group coughed but nobody in the PS-LMA-group (p < 0.00001). There was no difference with regard to postoperative sore throat. The insertion of the PS-LMA was easier compared to ET (p < 0.05), but we found no significant difference concerning insertion times. Fewer attempts at insertion of the gastric tube were necessary in the PS-LMA-group than in the ET-group (p < 0.01), whereas insertion times did not differ.

CONCLUSION

The PS-LMA is a convenient and practicable approach for anaesthesia in patients undergoing laparoscopic surgery.

Injektionsschmerz unter Propofol-MCT/LCT und Propofol-LCT - Vergleich einer Prophylaxe mit Lidocain

OBJECTIVE

Pain on injection is one of the most described side-effects of the intravenous application of propofol. This study was designed to assess the efficacy of lidocaine 40 mg in preventing incidence and severity of injection pain for two different propofol solvents.

METHODS

In a double-blind and prospective study 202 patients were enrolled and randomized to 4 different groups: group A receiving 2 ml NaCl 0.9 % and propofol-LCT (Disoprivan; AstraZeneca), group B 40 mg lidocaine and propofol-LCT, group C received 2 ml NaCl 0.9 % and propofol-MCT/LCT (Propofol-Lipuro, B. Braun Melsungen AG) and group D 40 mg lidocaine and propofol-MCT/LCT. According to the protocol, all patients were cannulated with a 18-G venous cannula at the dorsum of the hand and no other medicament was injected before the study drug. Time interval between test agents and propofol application in a dosage of 2 mg/kg was one minute. Severity of pain was evaluated during propofol injection over 30 seconds until loss of consciousness using a 4-point rating scale.

RESULTS

The incidence of injection pain did not differ between propofol-LCT and propofol-MCT/LCT (64 % and 53 %). Propofol-MCT/LCT significantly reduced the severity of pain compared to propofol-LCT (p < 0.05). The application of lidocaine resulted in a significant reduction in incidence (Propofol-MCT/LCT: 16 %; Propofol-LCT: 31 %) and severity of injection pain compared to placebo.

CONCLUSION

Propofol-MCT/LCT showed a significant advantage compared to propofol-LCT considering the severity of injection pain, but not in reducing the incidence of pain. The use of lidocaine resulted in a significant reduction of incidence and severity of injection pain for both propofol solvents.

[Prevention of post-operative nausea and vomiting. Randomised comparison of dolasetron versus dolasetron plus dexamethasone]

BACKGROUND

Postoperative nausea and vomiting (PONV) are frequent complications after operations. The aim of this study was to assess the efficacy of combined dolasetron plus dexamethasone versus dolasetron alone with respect to the incidence and severity of emetic symptoms and patients satisfaction.

METHODS

In a prospective, randomised, double-blind study, 150 patients scheduled for hysterectomy or breast surgery were allocated to one of the following two groups: group A received 50 mg dolasetron orally and group B 50 mg dolasetron orally plus 8 mg dexamethasone intravenously. The follow-up was for 24 h after surgery.

RESULTS

In group A PONV was significantly more frequent (28%) compared to group B (12.0%). The incidence of vomiting was significantly lower in patients receiving dolasetron plus dexamethasone (0%) in comparison to patients receiving dolasetron (8.0%). Furthermore,patients satisfaction was significantly higher in group B compared to group A. About 6 or 7 patients need to be treated with additional dexamethasone instead of a placebo for one patient to benefit from this intervention (i.e. to stay free from PONV) who otherwise would have suffered from PONV.

CONCLUSIONS

Combining oral dolasetron with intravenous dexamethasone further improves the antiemetic efficacy of dolasetron. With a number-needed-to-treat of about 6 the additional benefit might be considered clinically relevant.

Prevention of propofol-induced injection pain by remifentanil: a placebo-controlled comparison with lidocaine

In a randomised, double-blind study we compared the efficacy of continuous remifentanil infusion (0.25 microg x kg(-1) x min(-1) with 40 mg lidocaine and placebo in the prevention of injection pain due to intravenous propofol administration (1.5-2 mg x kg(-1)) in 155 patients scheduled for elective surgery. Pain severity was evaluated using a four-point scale. The incidence of injection pain was 62% in the placebo group and could be reduced significantly by using remifentanil (30%; p < 0.0015) or lidocaine (33%; p < 0.005). Analysis of the pain scores showed a significant difference between remifentanil and placebo (p < 0.00005) as well as between lidocaine and placebo (p < 0.0002). There was no significant difference between remifentanil and lidocaine. Remifentanil provided effective pain relief, comparable with lidocaine, and is an alternative as part of an intravenous anaesthesia regimen to using another concomitant drug.

[Dolasetron reduces pain on injection of propofol]

OBJECTIVE

Pain on injection is a well known side-effect of propofol. The present study was designed to assess the efficacy of dolasetron, a 5-HT 3 -antagonist, in prophylaxis of pain on injection of propofol compared with lidocaine and placebo.

METHODS

Prospective, randomised, double-blinded study including 150 patients randomly assigned to one of three groups: Group A received 12.5 mg dolasetron, group B 40 mg lidocaine and group C saline 0.9 % as placebo. After occluding the venous drainage the test medication was given. The occlusion was released after 1 min and 2.0 mg/kg Propofol was administered over a period of 30 sec. The patients were asked whether they felt any pain during the administration. Pain on injection was judged by using a four-point scale.

RESULTS

Incidence of pain on injection as well as the severity of pain was significantly reduced by lidocaine (62 % pain free) compared with placebo (28 %). Severity, but not incidence of pain on injection was significantly reduced by dolasetron (50 %) compared with placebo. There was no significant difference between dolasetron and lidocaine.

CONCLUSION

Dolasetron and lidocaine were effective in preventing pain of injection secondary to propofol.

Effects of sodium nitroprusside-induced controlled hypotension on pancreatic function assessed by pancreatitis-associated protein in patients undergoing radical prostatectomy

BACKGROUND AND OBJECTIVE

Controlled hypotension may alter organ blood flow and tissue oxygenation. The aim of the study was to investigate whether induced hypotension using sodium nitroprusside alters pancreatic function assessed by pancreatitis-associated protein concentrations in the blood.

METHODS

Thirty patients undergoing elective radical prostatectomy were allocated randomly into two groups: (a) hypotension group: sodium nitroprusside was administered to lower mean arterial pressure to approximately 50 mmHg; (b) control group: no hypotension was used, mean arterial pressure was kept > 70 mmHg. Pancreatitis-associated protein and lipase were measured in arterial blood samples: after induction of anaesthesia (T1), at the end of surgery (T2), 2 h (T3) and 24 h (T4) postoperatively.

RESULTS

Pancreatitis-associated protein plasma concentrations increased significantly in patients in the hypotensive group (from 2.8 +/- 1.1 to 5.5 +/- 2.0 micrograms L-1 at T4) and pancreatitis-associated protein plasma concentrations were significantly higher in comparison with controls (5.5 +/- 2.0 versus 3.5 +/- 2.4 micrograms L-1) at T4. Lipase concentrations showed a similar course in both groups. None of the patients showed clinical signs of pancreatitis.

CONCLUSIONS

Controlled hypotension during surgery was associated with a small but significant increase in pancreatitis-associated protein compared with controls. The absence of concomitant elevation in lipase concentrations and a lack of clinical evidence of pancreatitis damage suggest that hypotension induces mild pancreatic stress.

Urapidil does not prevent postanesthetic shivering: a dose-ranging study

PURPOSE

To investigate the effect of 0.2 mg x kg(-1), 0.3 mg x kg(-1) and 0.4 mg x kg(-1) urapidil on the incidence and severity of postanesthetic shivering.

METHODS

One hundred and fifty patients (ASA I-III) scheduled for elective abdominal, urologic or orthopedic surgery under standardized general anesthesia were randomly allocated to one of five groups (each group n=30) using a double-blind protocol: group A received 0.2 mg x kg(-1) urapidil, group B: 0.3 mg x kg(-1) urapidil, group C: 0.4 mg x kg(-1) urapidil, group D: 3 microg x kg(-1) clonidine (positive control group), and group E: saline 0.9% as placebo (negative control group). Postanesthetic shivering was scored using a five-point scale.

RESULTS

Twelve patients of group A, 11 of group B, nine of group C, three of group D and 14 of group E showed signs of postanesthetic shivering. Postanesthetic shivering was significantly decreased in the clonidine group compared to the three urapidil groups and the placebo group. Significantly less patients treated with clonidine needed anti-shivering therapy. There were no significant differences between the urapidil and placebo groups. Therapeutic interventions for hemodynamic effects were not required in any group. Time to extubation, but not time to discharge, was prolonged in the clonidine group.

CONCLUSION

Urapidil showed no beneficial effect on shivering in any of the doses evaluated, whereas prophylactic administration of clonidine was effective in preventing postanesthetic shivering.

Effects of postoperative sedation with propofol and midazolam on pancreatic function assessed by pancreatitis-associated protein

This prospective randomised controlled study evaluated the effects of postoperative sedation with propofol and midazolam on pancreatic function. We studied 42 intensive care unit patients undergoing elective major surgery who were expected to be sedated postoperatively. Patients were randomly assigned to a propofol group (n = 21) or a midazolam group (n = 21). To assess pancreatic function, the following parameters were measured: pancreatitis-associated protein, amylase, lipase, cholesterol and triglyceride prior to start of sedation on the intensive care unit, 4 h after the sedation was started and at the first postoperative day. Patients in the propofol group received on average (SD) 1292 (430) mg propofol and were sedated for 9.03 (4.26) h. The midazolam group received 92 (36) mg midazolam and were sedated for 8.81 (4.68) h. Plasma cholesterol concentrations did not differ significantly between groups. Triglyceride plasma levels 4 h after the start of infusion were significantly higher in the propofol group (140 (54) mg.dl(-1)) than the midazolam-treated patients (81 (29) mg.dl(-1)), but were within normal limits. There were no significant differences between the two groups regarding amylase, lipase and pancreatitis-associated protein plasma concentrations at any time. No markers of pancreatic dysfunction were outside the normal range. We conclude that postoperative sedation with propofol induced a significant increase of serum triglyceride levels but that pancreatic function is unchanged with standard doses of propofol.

Placebo-controlled comparison of dolasetron and metoclopramide in preventing postoperative nausea and vomiting in patients undergoing hysterectomy

BACKGROUND AND OBJECTIVE

In a randomized, placebo-controlled, double-blind trial, we compared the efficacy of dolasetron and metoclopramide in preventing postoperative nausea and vomiting in women undergoing hysterectomy.

METHODS

Patients were allocated randomly to one of three groups: group A (n = 50) received 50 mg dolasetron orally, group B (n = 50) received 20 mg metoclopramide intravenously and placebo orally, group C (n = 50) received placebo orally. If patients complained of retching or vomiting, or if patients demanded an antiemetic, 1.25 mg droperidol was administrated intravenously. To quantify postoperative nausea and vomiting the following score was used: 0 = no nausea, 1 = nausea, 2 = retching, 3 = single vomiting, 4 = multiple vomiting. The Raatz test was used to analyse postoperative nausea and vomiting (PONV) scores.

RESULTS

Dolasetron reduced the postoperative nausea and vomiting score significantly (P < 0.02 vs. metoclopramide; P < 0.0001 vs. placebo). Metoclopramide also reduced the postoperative nausea and vomiting score (P < 0.02 vs. placebo). Fisher's exact test showed a significant reduction of vomiting in the dolasetron group compared with metoclopramide-treated patients (P < 0.007) and placebo-treated patients (P < 0.000006) and a significantly lower rate of nausea in comparison to the placebo group (P < 0.009). There were no significant differences between the metoclopramide and the placebo groups (in Fisher's exact test). The use of postoperative droperidol per patient was significantly lower in the dolasetron group (P < 0.04 vs. metoclopramide; P < 0.0001 vs. placebo) than in the metoclopramide (P < 0.02 vs. placebo) and in the placebo groups.

CONCLUSIONS

Oral dolasetron is more effective than either metoclopramide given intravenously or placebo for preventing vomiting after hysterectomy. It also was significantly superior to either metoclopramide or placebo concerning the PONV score and the need for droperidol rescue.

Retracted: Price development in important anesthesia and critical care medicine journals in comparison to journals of other disciplines

BACKGROUND

In today's climate of financial restrictions, libraries and individual subscribers complain about the price increase of scientific journals. The development in prices of anesthesia/critical care journals was analysed over the past 6 years and compared to prices of some journals of other disciplines.

METHODS

Important journals in the categories Anesthesiology, Emergency Medicine & Critical Care, Surgery, Medicine (General), and Cardiac & Cardiovascular Systems listed in the 1999 Science Citation Index of Journal Citation Report were included and prices for the years 1995 to 2000 were analysed.

RESULTS

Increase in prices ranged from +13% to +199%. The mean increase in journal prices was lowest in the category Anesthesiology (+61%), higher in the category Critical Care (+73%), and highest in the category Medicine, General (+101%). Changes in the impact factor (IF) varied widely, ranging from a decrease (Lancet: -43%; J Neurosurg Anesth: -44%) to a tremendous increase (e.g. Reg Anesth +165%; Ann Emerg Med +149%). The journals' size (number of articles or pages) did not increase proportionally with the increase in prices.

CONCLUSION

A disproportionate rise in journal prices was seen over the past 6 years. The large increase in cost may have multiple reasons. The rapidly increasing cost of research journals may affect research quality because economic pressure may result in reduction in availibility of information due to cancellation of subscriptions to journals.

[German publications in leading English language journals]

BACKGROUND AND OBJECTIVE

The per capita publication output of German medical research is low compared not only to the English-speaking nations but also to Austria and Switzerland. We assessed the publications from German universities in the leading English language general medical journals: New England Journal of Medicine (NEJM), Lancet, Journal of the American Medical Association (JAMA), and British Medical Journal (BMJ).

METHODS

Medline (1988-5/2000) was searched for journal-articles with German origin published in the above journals and manually classified as to institution and speciality.

RESULTS

372 publications from Germany were found. 216 had been published in Lancet, 87 in NEJM, 52 in BMJ, and 17 in JAMA. 58 were excluded (2 from British military hospitals in Germany, 2 from pharmaceutical companies, 2 from physician associations, 18 from non-university basic research institutions or government agencies, 3 from non-medical university departments, 30 from non-university hospitals, 1 from a transfusion service of the German Red Cross). The remaining 314 publications were from 34 universities. The most speciality was internal Medicine with 140 university publications, the most represented university was the Ludwig-Maximilians-University in Munich with 43 publications. 5 universities had no publications in the analysed journals.

CONCLUSION

Large differences were found between the German universities with respect to publications in the leading English Language general medical journals.

[German language publications of German university departments of anesthesiology]

OBJECTIVE

To evaluate contributions of German university departments of anesthesiology to the German language literature.

METHODS

Using Medline (Silverplatter, volumes 1988-1997 of the 1999 edition) we searched for (journal-article IN SO) AND ((anesth* OR anasth* OR anaesth*) in AD) AND (LA-German). The publications found were manually evaluated for address. The "Jahrbuch der Anästhesiologie und Intensivmedizin" (1992-1995) was evaluated for the number of staff members (anaesthesiologists, residents and non-physician scientists).

RESULTS

The total number of publications was about 200/year. Individual departments contributed very differently (range: 0.6 publications/year to 14.8 publications/year). The department with the highest per capita output had about 0.4 Medline-indexed papers per scientist and year, the department with the lowest per capita output had about 0.02 papers per scientist and year.

CONCLUSION

There is a great difference with respect to total publication count. The differences in total publication count can only in part be explained by different size of the departments. Even the leading department had far less than 1 paper per scientist and year.

Retracted: Changes in the impact factor of anesthesia/critical care journals within the past 10 years

BACKGROUND

The impact factor (IF) is published by the Institute for Scientific Information (ISI). There is a tendency to assess quality of scientific journals with the help of the IE An analysis of the changes in the IF over time in the different specialities may help to further enlighten the worth and problems of the IE METHODS: The IFs listed under the subheadings Anesthesiology and Emergency Medicine & Critical Care in the Science Citation Index - Journal Citation Report were descriptively analysed over the past 10 years. Additionally, IFs of some other important journals (subheadings Surgery, Cardiovascular, General Medicine) were analysed.

RESULTS

The IF of most of the journals showed a constant increase over the years (average in Anesthesiology: +65%; average in Emergency Medicine & Critical Care: +145%). IFs of the highest ranked journals of other specialities showed a similar increase over the years (average in surgical journals: +56%; average in cardiac journals: +59%; average in general journals: +40%). More Anesthesiology and Emergency Medicine & Critical Care journals originated from the USA show an IF >2.0 over the past 10 years than do European journals.

CONCLUSION

Although the value of the IF is highly controversial, it is a frequently used tool to assess rating of a medical journal. Anesthesiology and Emergency Medicine & Critical Care journals showed a continuous increase in the IF over the past 10 years.

Hemodynamics, intramucosal pH and regulators of circulation during perioperative epidural analgesia

PURPOSE

To evaluate the effects of perioperative epidural analgesia on hemodynamics, splanchnic perfusion and regulators of circulation.

METHODS

Twenty patients undergoing aortic surgery were randomised into two groups: epidural analgesia group (EAG): epidural analgesia with bupivacaine (15 ml, 0.125%) was started before surgery. Eight and 16 hr postoperatively 10 ml bupivacaine 0.125% and 1 mg morphine were given. Control group (COG): patients received no epidural catheter. Monitoring included pulmonary artery catheter and gastric tonometer. Norepinephrine, epinephrine, renin, ADH, ANP and endothelin were measured: before epidural analgesia (T0), before aortic clamping (T1), 20 min after aortic clamping (T2), after declamping the first leg (T3), at end of surgery (T4), one hour (T5) and 24 hr postoperatively (T6).

RESULTS

At T5 mean arterial blood pressure decreased in EAG compared with baseline (86 +/- 16 to 75 +/- 8 mmHg) and compared with COG (75 +/- 8 vs 84 +/- 11 mmHg). At T2 pulmonary capillary wedge pressure and cardiac index increased and at T6 decreased in both groups. Systemic vascular resistance decreased at T I and at T3-T5 in EAG compared with COG and at T1 and T3-T6 to baseline (1472 +/- 448 to 1027 +/- 184 dyn x sec x cm(-5) x m(-2)). In EAG and in COG, pHi decreased compared with baseline but without group differences. In both groups, epinephrine, norepinephrine, renin, and ADH levels increased from baseline. Endothelin and ANP levels showed no changes.

CONCLUSIONS

Perioperatively administrated epidural bupivacaine has no beneficially effects on hemodynamics, pHi or release of regulators of circulation.

Influence of dopexamine on hemodynamics, intramucosal pH, and regulators of the macrocirculation and microcirculation in patients undergoing abdominal aortic surgery

OBJECTIVE

To investigate whether dopexamine hydrochloride beneficially influences splanchnic perfusion and regulators of the macrocirculation and microcirculation in patients undergoing surgery of the abdominal aorta.

DESIGN

Prospective, blinded, and randomized study.

SETTING

University-affiliated hospital.

PARTICIPANTS

Twenty patients undergoing elective abdominal aortic surgery.

INTERVENTIONS

The patients were randomized to one of two groups. In the dopexamine group (DOP, n = 10), dopexamine, 1 microg/kg/min, was started before surgery and continued for 24 hours. In the control group (COG, n = 10), patients received saline solution as placebo. Extensive hemodynamic monitoring was carried out using a pulmonary artery catheter, and intramucosal pH was measured using a gastric tonometer. From arterial blood samples, important regulators of the circulation were measured before dopexamine was administered (T0), before aortic clamping (T1), 20 minutes after aortic clamping (T2), after declamping the first leg (T3), at the end of surgery (T4), 1 hour postoperatively (T5), and 24 hours postoperatively (T6).

MEASUREMENTS AND MAIN RESULTS

Heart rate increased significantly in DOP (63+/-16 to 84+/-18 beats/min). At T5, mean pulmonary artery pressure was significantly lower in DOP (15+/-6 mmHg) than in COG (22+/-6 mmHg). During aortic clamping, pulmonary capillary wedge pressure increased significantly in both groups. Cardiac index increased significantly from baseline only in the dopexamine patients. No significant differences between the groups were seen with regard to oxygenation parameters and intramucosal pH. Renin plasma levels increased significantly only in COG (46+/-32 to 99+/-55 microU/mL). Endothelin and atrial natriuretic peptide plasma levels showed no significant differences between the two groups. Atrial natriuretic peptide increased significantly only in DOP (366+/-171 pg/mL; COG, 159+/-71 pg/mL). Antidiuretic hormone, norepinephrine, and epinephrine plasma levels increased significantly from baseline in both groups, without showing significant differences between the groups.

CONCLUSIONS

In patients undergoing abdominal aortic surgery, prophylactic perioperative administration of dopexamine hydrochloride produced effects on hemodynamics but without improving oxygenation and intramucosal pH. From the measured regulators of the circulation, only renin was beneficially affected.

A simple "new" method to accelerate clearance of carbon monoxide

The currently recommended prehospital treatment for carbon monoxide (CO) poisoning is administration of 100% O(2). We have shown in dogs that normocapnic hyperpnea with O(2) further accelerates CO elimination. The purpose of this study was to examine the relation between minute ventilation (V E) and the rate of elimination of CO in humans. Seven healthy male volunteers were exposed to CO (400 to 1,000 ppm) in air until their carboxyhemoglobin (COHb) levels reached 10 to 12%. They then breathed either 100% O(2) at resting V E (4.3 to 9.0 L min) for 60 min or O(2) containing 4.5 to 4.8% CO(2) (to maintain normocapnia) at two to six times resting V E for 90 min. The half-time of the decrease in COHb fell from 78 +/- 24 min (mean +/- SD) during resting V E with 100% O(2) to 31 +/- 6 min (p < 0. 001) during normocapnic hyperpnea with O(2). The relation between V E and the half-time of COHb reduction approximated a rectangular hyperbola. Because both the method and circuit are simple, this approach may enhance the first-aid treatment of CO poisoning.

The effect of In vitro hemodilution with gelatin, dextran, hydroxyethyl starch, or Ringer's solution on Thrombelastograph

To determine the effects of progressive in vitro hemodilution with various plasma substitutes on whole blood coagulation, blood was obtained from six healthy volunteers. The Thrombelastograph((R)) (TEG; Haemoscope Corp., Morton Grove, IL) variables of reaction time, coagulation time, maximum amplitude, and growth angle were determined. The following plasma substitutes were tested: two gelatin solutions (4% gelatin polysuccinate and 5.5% oxypolygelatin); two dextrans (10% dextran 40 and 6% dextran 60); and five hydroxyethyl starch (HES) preparations (6% HES 70/0.5-0.55, 3% HES 200/0.5, 6% HES 200/0.5, 10% HES 200/0.5, and 6% HES 450/0.7). Ringer's solution was also tested to assist analyzing the intrinsic effect of colloid molecules on blood coagulation. The dilution ratios of citrated blood volume to plasma substitute volume were 10:2, 10:4, and 10:10. Blood coagulation was affected by plasma substitutes when the dilution ratios of citrated blood volume to colloid solution volume were 10:4 and 10:10. TEG variables did not change significantly after in vitro hemodilution with lactated Ringer's solution. The tested gelatin solutions showed less intrinsic effect on blood coagulation than other plasma substitutes. All HES preparations showed similar intrinsic effects as 6% dextran 60. The plasma substitute of 10% dextran 40 had the strongest effect on coagulation. Coagulation time was the most markedly affected TEG variable. Blood coagulation may be compromised when the dilution ratio of blood volume to colloid solution volume is >10:4. Whereas gelatin solutions have less intrinsic effect on blood coagulation, 10% dextran 40 has the strongest effect on coagulation.

IMPLICATIONS

Blood coagulation may be compromised when the dilution ratio of blood volume to colloid solution volume is >10:4. Whereas gelatin solutions have less intrinsic effect on blood coagulation than hydroxyethyl starch or dextran, 10% dextran 40 has the strongest effect on coagulation.

A comparison of urapidil, clonidine, meperidine and placebo in preventing postanesthetic shivering

This placebo-controlled study was performed to evaluate the efficacy of urapidil compared with clonidine and meperidine in preventing postanesthetic shivering, which is common after anesthesia administration and may be very distressing. We studied 120 patients undergoing elective abdominal or orthopedic surgery under standardized general anesthesia. After surgery, patients were randomly assigned to one of four groups (each group n = 30) using a double-blinded protocol: Group A received 0.2 mg/kg urapidil; Group B, 3 microg/kg clonidine; Group C, 0.4 mg/kg meperidine; and Group D, saline 0.9% as placebo. Postanesthetic shivering was scored by using a five-point scale. Clonidine and meperidine significantly reduced the incidence and the severity of shivering in comparison with placebo, whereas there were no significant differences between the urapidil and placebo groups. Both clonidine and meperidine caused a significantly prolonged emergence time (13.4 +/- 5.8 and 13. 3 +/- 5.0 min, respectively) compared with placebo (10.4 +/- 5.3 min) and urapidil (11.4 +/- 2.9 min). We confirmed that both clonidine and meperidine are effective in preventing postanesthetic shivering, whereas urapidil, in our setting and dosage, was not effective. Patients who received clonidine or meperidine had a prolonged emergence time. In the dosage used, urapidil seems to be unable to prevent postanesthetic shivering.

IMPLICATIONS

Shivering (irregular muscle activity) is common after surgery and anesthesia. This study compared urapidil (an antihypertensive drug) as a prophylaxis with two established antishivering drugs (meperidine and clonidine) and placebo. In the dosage used, we were unable to show a significant benefit of urapidil.

Acute phase response to nitroprusside-induced controlled hypotension in patients undergoing radical prostatectomy

This study evaluated the effects of sodium nitroprusside-induced controlled hypotension on the acute phase response in patients undergoing radical prostatectomy. Thirty patients were randomly allocated to two groups, a hypotension group (mean arterial blood pressure was adjusted to 50 mmHg) and a control group (mean arterial blood pressure > 70 mmHg). C-reactive protein increased significantly in the hypotension group from 0.13 (0.23) to 9.85 (2.84) microg x ml-1 and in the control group from 0.15 (0.27) to 7.38 (3.02) microg x ml-1. In both groups, serum amyloid A increased significantly, but levels were higher in the hypotension group [585 (125) microg x l-1] than in the control group [460 (187) microg x l-1]. Interleukin-6 increased significantly in both groups, but was higher in the hypotension group [139 (124) pg x ml-1] than the control group [56 (27) pg x ml-1]. Elastase showed no significant changes in the control group but in the hypotension group there was a significant increase from 65 (51) to 122 (75) ng x ml-1. Sodium nitroprusside-induced hypotension was associated with a more pronounced acute phase reaction.

Massive postoperative swelling of the tongue: manual decompression and tactile intubation as a life-saving measure

Massive swelling of the tongue due to haemorrhage is a rare but potentially fatal complication secondary to trauma, surgery, tumour invasion or uncontrolled anticoagulant therapy. This article presents a report of bleeding from the left lingual artery secondary to elective excision of a lipoma of the floor of the mouth and subsequent life-threatening upper airway obstruction. In this case, the upper airway obstruction was managed by manual decompression of the tongue and tactile nasal intubation. To our knowledge this case provides the first description of using this method in life-threatening upper airway obstruction caused by massive haemorrhagic swelling of the tongue.

A randomised comparison of three laryngoscopes with the Macintosh

The Macintosh laryngoscope blade was compared with three modified blades--the Bizzarri-Giuffrida, the 'Improved Vision' Macintosh, and the Wiemers blade. Before and after a training session 24 participants intubated a Laerdal Airway Management Trainer with the four blades in random order. Intubation time was measured, oesophageal malpositions and 'clicks' indicating possible teeth damage, were counted. Each participant scored the handling of each blade on a 6-point scale (1 = very good, 6 = very poor). Intubation times before training were 10.6 +/- 5.3 s for the Macintosh, 16.7 +/- 9.2 s for the Bizzarri-Giuffrida, 13.3 +/- 9.0 s for the 'Improved Vision' Macintosh and 11.7 +/- 6.1 s for the Wiemers. Intubation times after training were 7.1 +/- 2.5 s for the Macintosh, 10.6 +/- 5.4 s for the Bizzarri-Giuffrida, 8.1 +/- 3.4 s for the 'Improved Vision' Macintosh and 7.6 +/- 2.5 s for the Wiemers. The handling scores were: 2.0 +/- 0.8 for the Macintosh, 3.9 +/- 1.2 for the Bizzarri-Giuffrida, 2.1 +/- 0.8 for the 'Improved Vision' and 2.3 +/- 0.8 for the Wiemers. In regard to the intubation time before training (P < 0.02), the intubation time after training (P < 0.003), and handling (P < 0.0005), the Bizzarri-Giuffrida was significantly inferior to the Macintosh. The 'Improved Vision' Macintosh and the Wiemers were not significantly different to the Macintosh. No significant difference was seen for oesophageal malpositioning and 'clicks' between any of the blades.

Nefopam and clonidine in the prevention of postanaesthetic shivering

Postanaesthetic shivering affects up to 70% of patients after general anaesthesia, and may be very distressing. Various drugs have been used to treat or prevent postanaesthetic shivering, but the ideal one has not yet been found. Sixty patients undergoing elective abdominal or orthopaedic surgery under general anaesthesia were included in a randomised, double-blind study. Patients received clonidine (3 microgram.kg-1), nefopam (0.15 mg.kg-1) or saline 0.9% as a placebo at the end of surgery, prior to extubation. Nefopam and clonidine significantly reduced the incidence and severity of shivering in comparison with the placebo. The recovery time, between the end of anaesthesia and extubation, was significantly longer in the clonidine-treated patients [13.6 (5.2) min] than in either the nefopam [9.6 (2.8) min] or the placebo [10.0 (5.4) min] groups. Mean arterial blood pressure and heart rate were significantly lower in the clonidine group compared with both other groups. Our results suggest that nefopam and clonidine are effective in the prevention of postanaesthetic shivering. However, following clonidine administration the recovery time was prolonged and hypotension was significantly greater than after nefopam.

[Rudolf Eisenmenger's biomotor--predecessor of active compression-decompression cardiopulmonary resuscitation]

Lerman mentioned in 1994 Eisenmenger's Biomotor as a precursor of Active Compression-Decompression Cardiopulmonary Resuscitation (ACD-CPR). We attempted to find additional information. We checked Medline 1966-1998, Quarterly Cumulative Index 1916-1926, Quarterly Cumulative Index Medicus 1927-1950 for publications of Eisenmenger and the secondary literature thereof. Rudolf Eisenmenger (1871-1946) published in 1903 a "Device for Artificial Respiration" consisting of an air-tight thoraco-abdominal shield and a foot-operated bellows for generation of alternating pressure and vacuum on the abdomen and lower thorax. He proposed use of the device for patients in cardiopulmonary arrest caused by drowning or intoxication. The device was patented and in 1904 made commercially available. In 1911 he published a successful resuscitation with his device after one hour of "Vacuum and Pressure Massage of the Abdomen" in a case of attempted suicide by hanging. The foot-operated bellows was replaced by an electromotor (hence "Biomotor") in 1924. Experiments on dogs in cardiac arrest were published in 1929. With the methods available not only "normal" tidal volumes and blood pressure, but also carbon dioxide exhalation and transport of intravenous dye to all parts of the body were shown. In 1939 an eight part series was published, describing use of the device as a respirator in several hospitals. Eisenmenger was the first to propose ACD-CPR, to build a device to perform ACD-CPR and to use it successfully in a patient. Furthermore, he was the first to propose the "cardiac pump theory" and the first to recognize the connection of carbon dioxide exhalation, cardiac output and prognosis of cardiac arrest.

[Prevention of postoperative nausea and vomiting after hysterectomy with oral dolasetron, intravenous dehydrobenzperidol or a combination of both substances]

OBJECTIVE

PONV is a frequent postoperative complication. The aim of this study was to assess the efficacy of oral dolasetron in comparison to intravenous droperidol (DHB) and to a combination of both drugs for prophylaxis of PONV.

METHODS

80 patients (ASA I-III) were randomly allocated to one of four groups and received the following medication: group A: 50 mg dolasetron was given orally 45-60 minutes before anaesthesia was induced, group B: 2.5 mg i.v. DHB + placebo p.o. was administered while inducing anaesthesia (positive control group), group C: 50 mg dolasetron was given 45-60 minutes before anaesthesia was induced and 2.5 mg i.v. DHB was given while inducing anaesthesia, group D: placebo tablet was administered 45-60 minutes before anaesthesia was induced (negative control group). PONV was assessed using a 5-point score: 0 = no symptoms, 1 = nausea, 2 = retching, 3 = vomiting, 4 = multiple vomiting. Metoclopramid was given as antiemetic if a patient reached two or more score points.

RESULTS

PONV scores were significantly lower in group A and C (p < 0.001) compared to the control group. Patients treated with DHB showed a significantly lower PONV score in comparison to the placebo treated patients (p < 0.05). Between the groups A, B and C we found no significantly different PONV scores. Postoperative consumption of metoclopramid was significantly lower in the groups A (2.4 +/- 5.2 mg) and C (1.0 +/- 3.1 mg) than in the placebo group (6.0 +/- 6.8 mg), whereas between group B (3.0 +/- 5.7 mg) and D we found no significant differences.

CONCLUSIONS

Single dose of oral dolasetron and single dose of intravenous DHB reduced PONV effectively, in patients undergoing gynaecologic surgery. A combination of dolasetron and DHB has no better effect than a single dose of oral dolasetron. Contrary to DHB the application of dolasetron decreased the postoperative antiemetic requirement significantly.

Intubation with transillumination: nasal or oral?

Transillumination-guided intubation is a useful back-up method when laryngoscopic intubation proves to be difficult or impossible. The Trachlight (Laerdal, N-4001 Stavanger, Norway) is suited for both nasal and oral use. Intubation times (IT) and success rates (SR) for nasal and oral intubation with the Trachlight were compared. Twenty-four medical students, inexperienced in intubation were instructed in the use of the Trachlight. A demonstration also was performed. Subsequently, they were asked to intubate a Laerdal Airway Management Trainer (Laerdal, Stavanger, Norway) using the Trachlight. Each student intubated 10 times orally and 10 times nasally (five times through the right and five times through the left nostril). The succession of the students was randomized. The intubation times were measured and the position of the tube noted. Nasal and oral intubation times for the tenth trial (steady state conditions) were compared using the rank-order test for paired observations. Oral and nasal success rates were compared using the sign test for paired observations. The differences between nasal and oral intubation concerning intubation time and the success rates were not significant. Nasal intubation with the Trachlight seems to be more difficult than the oral intubation.

Meconium and amniotic fluid embolism: effects on coagulation in pregnant mini-pigs

OBJECTIVE

A hallmark of amniotic fluid embolism is the induction of coagulation defects. Little is known about the nature of these defects or the causative agent or agents. The purpose of this study was to assess the effects of meconium containing (native) meconium-amniotic-fluid infusion (MAFI) and meconium-free (centrifuged) amniotic-fluid infusion (AFI) on the coagulation system in the mini-pig model.

DESIGN

Laboratory study.

SETTING

University institute animal laboratory.

SUBJECTS

Near-term pregnant Göttingen bred mini-pigs in three groups (control, MAFI, AFI) of six animals each.

INTERVENTIONS

After induction of anesthesia, amniotic fluid was collected by cesarean section in all animals. Depending on the group, animals received either Ringer's solution (control), native amniotic fluid (MAFI), or centrifuged amniotic fluid (AFI) via an ear vein.

MEASUREMENTS AND MAIN RESULTS

Blood samples were taken from a central vein before infusion (baseline), immediately after infusion, every 10 mins until 90 mins after infusion, and finally, every 20 mins until 150 mins after infusion. The following parameters were measured: Platelets, partial thromboplastin time, prothrombin time, fibrinogen, factors V, VII, VIII, antithrombin III, and protein C. The values relative to baseline in the MAFI and AFI groups were compared with control by rank order test. A p<.05 was considered statistically significant. Compared with the control group, platelets were lower in the MAFI group (p<.005), PTT was prolonged in both the MAFI and AFI groups (p<.005), fibrinogen was lower in both the MAFI and AFI groups (p<.05), prothrombin index was lower (i.e., prothrombin time was prolonged) in the MAFI group (p<.05), and protein C was lower in the MAFI group (p<.005).

CONCLUSIONS

Both MAFI and, to a much lesser extent, AFI cause an activation of coagulation in mini-pigs. The changes induced by meconium-free AFI are probably not sufficient to explain the high mortality of the condition.

[Prophylactic nefopam administration for post-anesthetic shivering]

PURPOSE

Shivering is a frequent postanaesthetic complication. Its definite reason is unknown. Patients with cardiovascular or pulmonary diseases are endangered by postanaesthetic shivering. The aim of this study was to assess the efficacy of nefopam in prophylaxis of shivering. Additionally we investigated the influence of nefopam on haemodynamic parameters and on the time until extubation.

METHODS

30 patients (ASA I-II) were randomly allocated in a double-blind fashion to one of two groups to receive directly after the end of isoflurane application either nefopam (0.15 mg/kg) or placebo (0.9% saline). The period of anaesthesia had to be longer than 60 minutes. All patients received a premedication with lorazepam (0.02 mg/kg) 30-45 minutes prior to surgery. Induction of anaesthesia was standardised: fentanyl (3 micrograms/kg), thiopentone (5 mg/kg), atracurium (0.4 mg/kg). Intraoperatively a mixture of isoflurane, nitrous oxide (60%) and oxygen was used to maintain anaesthesia. The following parameters were evaluated: Age, sex, duration of operation and anaesthesia and the time between the end of application of volatiles and extubation. Heart rate (HR), mean arterial blood pressure (MAP), rectal temperature and O2-saturation were measured at predefined data points. Postoperatively the consumption of analgesic was documented. The severity of shivering was classified in five grades.

RESULTS

In the control-group nine patients shivered (60%), whereas in the nefopam group only one patient (6.6%) shivered (p < 0.05). In comparison to the placebo group we observed in the nefopam group a significantly decreased HR 30 and 60 minutes postoperatively (p < or = 0.007 and p < or = 0.002). We did not observe prolonged awakening in the nefopam-treated patients. MAP and O2-saturation showed similar reactions in both groups.

CONCLUSION

The data indicate that prophylactic administration of nefopam can suppress postanaesthetic shivering. Prolonged awakening was not observed.

Preliminary observations on the Colibri CO2-indicator

The performance of a new colorimetric CO2-indicator (Colibri) was assessed in mini-pigs. It performed well during 8-hour procedures. Neither nitrous oxide, nor halothane, nor carbon monoxide, nor intratracheal application of drugs (epinephrine, atropine, lidocaine, and naloxone) interfered with its function. It gave a distinct color change at high ventilation frequencies up to 120/min. The only problem observed was difficulty in matching the colors displayed with the comparison color chart provided. The Colibri's performance seems at least equal to that of the EasyCAP detector, although both devices share some disadvantages (no alarms, semiquantitative, difficult reading in the dark). After initial control of endotracheal tube position by an esophageal detector device, both the Colibri and the EasyCAP seem suited for monitoring of ventilation and circulation if quantitative capnometry is unavailable.