Dan Benhamou

Major complications of regional anesthesia in France: The SOS Regional Anesthesia Hotline Service.

Background Several previous surveys have estimated the rate of major complications that occur after regional anesthesia. However, because of the increase in the use of regional anesthesia in recent years and because of the introduction of new techniques, reappraisal of the incidence and the characteristics of major complications is useful. Methods All French anesthesiologists were invited to participate in this 10-month prospective survey based on (1) voluntary reporting of major complications related to regional anesthesia occurring during the study period using a telephone hotline service available 24 h a day and managed by three experts, and (2) voluntary reporting of the number and type of regional anesthesia procedures performed using pocket booklets. The service was free of charge for participants. Results The participants (n = 487) reported 56 major complications in 158,083 regional anesthesia procedures performed (3.5/10,000). Four deaths were reported. Cardiac arrest occurred after spinal anesthesia (n = 10; 2.7/10,000) and posterior lumbar plexus block (n = 1; 80/10,000). Systemic local anesthetic toxicity consisted of seizures only, without cardiac toxicity. Lidocaine spinal anesthesia was associated with more neurologic complications than bupivacaine spinal anesthesia (14.4/10,000 vs. 2.2/10,000). Most neurologic complications were transient. Among 12 that occurred after peripheral nerve blocks, 9 occurred in patients in whom a nerve stimulator had been used. Conclusion This prospective survey based on a free hotline permanent telephone service allowed us to estimate the incidence of major complications related to regional anesthesia and to provide a detailed analysis of these complications.

Survey of Anesthesia-related Mortality in France

Background:This study describes a nationwide survey that estimates the number and characteristics of anesthesia-related deaths for the year 1999. Methods:Death certificates from the French national mortality database were selected from the International Classification of Diseases, Ninth Revision codes using a variable sampling fraction. Medical certifiers were sent a questionnaire (response rate, 97%), and the anesthesiologist in charge was offered a peer review (acceptance rate, 97%). Files were reviewed to determine the mechanism of each perioperative death and its relation to anesthesia. Mortality rates were calculated using the number of anesthetic procedures estimated from a national 1996 survey and compared with a previous (1978–1982) nationwide study. Results:Among the 4,200 certificates analyzed, 256 led to a detailed evaluation. The death rates totally or partially related to anesthesia for 1999 were 0.69 in 100,000 (95% confidence interval, 0.22–1.2 in 100,000) and 4.7 in 100,000 (3.1–6.3 in 100,000), respectively. The death rate increased from 0.4 to 55 in 100,000 for American Society of Anesthesiologists physical status I and IV patients, respectively. Rates increased with increasing age. Although concerns regarding aspiration of gastric contents remain, intraoperative hypotension and anemia associated with postoperative ischemic complications were the associated factors most often encountered. Deviations from standard practice and organizational failure were often found to be associated with death. Conclusion:In comparison with data from a previous nationwide study (1978–1982), the anesthesia-related mortality rate in France seems to be reduced 10-fold in 1999. Much remains to be done to improve compliance of physicians to standard practice and to improve the anesthetic system process.

Postoperative Analgesic THerapy Observational Survey (PATHOS): a practice pattern study in 7 central/southern European countries.

&NA; Surveys evaluating pain in hospitals keep on showing that postoperative pain (POP) remains undertreated. At the time when guidelines are edited and organisational changes are implemented, more recent data are necessary to check the impact of these measures on daily practice and needs for improvement. This prospective, cross‐sectional, observational, multi‐centre practice survey was performed in 2004–2005 in 7 European countries. It was conducted in surgical wards of a randomised sample of hospitals. Data on POP management practices following surgery in adult in‐patients were collected anonymously via a standardised multiple choice questionnaire. Among 1558 questionnaires received from 746 European hospitals, 59% were provided by anaesthetists and 41% by surgeons. There are no regular on‐site staff training programmes on POP management in the institution for 34% of the respondents, patients are systematically provided with POP information before surgery for 48% of respondents; balanced analgesia following major surgery and regular administration of analgesics are largely used; 25% of respondents have specific written POP management protocols for all patients in their ward; 34% of respondents say that pain is not assessed and 44% say that pain scores are documented in the patient’s chart. This largest ever performed survey confirms the extensive body of evidence that current POP management remains suboptimal and identifies needs for improvement on European surgical wards. However, the wide use of balanced analgesia and the regular administration of analgesics are indicators of ongoing change.

Difficult endotracheal intubation in patients with sleep apnea syndrome.

Although sleep apnea syndrome (SAS) is common, studies assessing the anesthetic management of these patients are rare and consist mainly of case studies. We performed a retrospective case-control study to determine the incidence of difficult intubation in SAS patients and to determine the relationship between the severity of SAS and the occurrence of difficult intubation. Among 113 patients included (36 and 77 in the SAS and control groups, respectively), difficult intubation occurred more often in SAS patients than in controls (21.9% versus 2.6%, respectively;P < 0.05). No relationship was found between the severity of SAS and the occurrence of difficult intubation. Disappointingly, no single factor was associated with the occurrence of difficult intubation in SAS patients. We conclude that SAS is a risk factor for difficult intubation.

Binding of Long-lasting Local Anesthetics to Lipid Emulsions

Background:Rapid infusion of lipid emulsion has been proposed to treat local anesthetic toxicity. The authors wanted to test the buffering properties of two commercially available emulsions made of long- and of long- and medium-chain triglycerides. Methods:Using the shake-flask method, the authors measured the solubility and binding of racemic bupivacaine, levobupivacaine, and ropivacaine to diluted Intralipid (Fresenius Kabi, Paris, France) and Medialipide (B-Braun, Boulogne, France). Results:The apparent distribution coefficient expressed as the ratio of mole fraction was 823 ± 198 and 320 ± 65 for racemic bupivacaine and levobupivacaine, and ropivacaine, respectively, at 500 mg in the Medialipide/buffer emulsion; and 1,870 ± 92 and 1,240 ± 14 for racemic bupivacaine and levobupivacaine, and ropivacaine, respectively, in the Intralipid/buffer emulsion. Decreasing the pH from 7.40 to 7.00 of the Medialipide/buffer emulsion led to a decrease in ratio of molar concentration from 121 ± 3.8 to 46 ± 2.8 for bupivacaine, and to a lesser extent from 51 ± 4.0 to 31 ± 1.6 for ropivacaine. The capacity of the 1% emulsions was 871 and 2,200 &mgr;m for the 1% Medialipide and Intralipid emulsions, respectively. The dissociation constant was 818 and 2,120 &mgr;m for racemic bupivacaine and levobupivacaine, and ropivacaine, respectively. Increasing the temperature from 20 to 37°C led to a greater increase in affinity for ropivacaine (55%) than for bupivacaine (27%). When the pH of the buffer was decreased from 7.40 to 7.00, the affinity was decreased by a factor of 1.68, similar for both anesthetics. Conclusions:The solubility of long-acting local anesthetics in lipid emulsions and the high capacity of binding of these emulsions most probably explain their clinical efficacy in case of toxicity. The long-chain triglyceride emulsion Intralipid appears to be about 2.5 times more efficacious than the 50/50 medium-chain/long-chain Medialipide emulsion. Also, because of their higher hydrophobicity, racemic bupivacaine and levobupivacaine seem to clear more rapidly than ropivacaine.

Early embolization and vasopressor administration for management of life-threatening hemorrhage from pelvic fracture.

BACKGROUND In this retrospective study, we reviewed our protocol for management of hemodynamically unstable patients with pelvic injury. METHODS We managed the patients with the same predetermined plan including controlled hemodynamic resuscitation with early use of vasopressors and pelvic angiography as a first-line treatment. RESULTS Of 311 patients with pelvic fracture, 32 hemodynamically unstable patients (10.3%) underwent pelvic angiography, which was followed by embolization in 25 cases. Angiography was successful for 24 patients (96%) and extrapelvic bleeding was diagnosed in 5 patients (15%). Three of six laparotomies performed before angiography were nontherapeutic. One of seven laparotomies performed after angiography was negative. CONCLUSION A protocol for management of patients with pelvic injury and hemodynamic instability that is associated with controlled resuscitation including vasopressor and early pelvic angioembolization is effective for treating pelvic hemorrhage and diagnosing extrapelvic hemorrhage. Further studies are needed to confirm the respective place of angiographic and surgical control of bleeding.

Clinical Assessment of the Ultrasonographic Measurement of Antral Area for Estimating Preoperative Gastric Content and Volume

BACKGROUND This prospective observational study aimed to assess the feasibility and performance of the ultrasonographic measurement of antral cross-sectional area (CSA) for the preoperative assessment of gastric contents and volume in adult patients and for the diagnosis of risk stomach (defined by the presence of solid particles and/or gastric fluid volume >0.8 ml/kg). METHODS A preoperative ultrasonographic measurement of the antral CSA was performed for each patient by a physician (L.B.) blinded to the history of the patient. Immediately after tracheal intubation, an 18-French multiorifice Salem tube was inserted and gastric contents were aspirated in five different patient positions; during this time, the patients epigastrium was massaged and the tube was moved backward and forward in the stomach. The relationship between the antral area and the volume of aspirated gastric contents was analyzed, as was the performance of ultrasonographic measurement of antral area for the diagnosis of risk stomach. RESULTS The measurement of antral CSA was performed on 180 of 183 patients. A significant positive relationship between antral CSA and aspirated fluid volume was found. The cutoff value of antral CSA of 340 mm(2) for the diagnosis of risk stomach was associated with a sensitivity of 91% and a specificity of 71%. The area under the receiver operating characteristic curve for the diagnosis of risk stomach was 90%. CONCLUSIONS The ultrasonographic measurement of antral CSA could be an important help for the anesthesiologist in minimizing the risk of pulmonary aspiration of gastric contents due to general anesthesia.

Ultrasound Guidance for Axillary Plexus Block Does Not Prevent Intravascular Injection

DIRECT visualization of anatomy by ultrasound during regional anesthesia was considered to likely minimize the incidence of complications of regional anesthesia due to needle misplacement. Neural impalements have been reported under direct vision of the brachial plexus. We report a case of inadvertent vascular puncture leading to a seizure during an ultrasound-guided axillary block.

The lateral approach to the sciatic nerve at the popliteal fossa: one or two injections?

UNLABELLED It has not been proven whether one or multiple nerve stimulations and injections provide a higher rate of complete sensory block in both major sciatic nerve sensory distributions below the knee when a popliteal sciatic nerve block is performed using the lateral approach. This prospective, randomized, single-blinded study compared the success rate of the sciatic nerve block using this approach when one or both major components of this nerve (i.e., tibial nerve and common peroneal nerves) are stimulated in 50 patients undergoing foot or ankle surgery. In Group 1 STIM, 24 patients received a single injection of 20 mL of a mixture of 2% lidocaine and 0.5% bupivacaine with 1:200,000 epinephrine after foot inversion had been elicited. In Group 2 STIM (n = 26), 10 mL of the same solution was injected after stimulation of each sciatic nerve component. For patients with complete sensory motor block, there was no difference in onset between groups. However, Group 2 STIM showed a greater success rate compared with the Group 1 STIM (2 STIM: 88% vs 1 STIM :54%; P = 0.007). When two stimulations were used, the onset time of anesthesia in the cutaneous distribution of the common peroneal nerves was shorter than in the tibial nerve (17.5 vs 30 min; P < 0.0001). We conclude that a two-stimulation technique provides a better success rate than a single-injection technique when a popliteal sciatic nerve block is performed using the lateral approach with 20 mL of local anesthetic. IMPLICATIONS A better success rate is achieved with a double stimulation technique than with a single injection for the sciatic nerve block via the lateral approach at the popliteal fossa when 20 mL of local anesthetics is used.

The clinical efficacy and pharmacokinetics of intraperitoneal ropivacaine for laparoscopic cholecystectomy.

Postoperative pain after laparoscopic surgery is less than after laparotomy, and patients may benefit from an intraperitoneal injection of local anesthetic. Thirty-seven ASA physical status I or II patients received in double-blinded fashion 20 mL of 0.9% saline solution (placebo), ropivacaine 0.25% (Rop 0.25%), or ropivacaine 0.75% (Rop 0.75%) immediately after trocar placement and at the end of surgery. We measured pain and morphine consumption until 20 h after surgery. Plasma ropivacaine concentrations were measured. The three groups were comparable for shoulder pain, parietal pain, and incidence of side effects. Visceral pain at rest, during cough, and on movement and total consumption of morphine were significantly smaller in Groups Rop 0.25% and Rop 0.75% when compared with Placebo. Although no adverse effect occurred in any patient, the largest dose led to large plasma concentrations of ropivacaine (2.93 ± 2.46 &mgr;g/mL and 3.76 ± 3.01 &mgr;g/mL after the first and second injection, respectively). We conclude that intraperitoneal administration of ropivacaine before and after surgery significantly decreases postoperative pain. Because the smaller dosage (2 × 50 mg) provided similar analgesia and was associated with significantly smaller plasma concentrations than the larger dosage (2 × 150 mg), this smaller dosage seems more appropriate.