Association between anesthesiologist age and litigation.

BACKGROUND: : The threat of being sued is a concern for many anesthesiologists. This paper asks whether litigation brought against anesthesiologists is associated with the age of the anesthesiologist. METHODS: : Institutional research ethics approval was granted. We obtained billing data for all procedures performed by specialist anesthesiologists stratified into three age groups (less than 51, 51-64, and 65 and older) from British Columbia, Quebec, and Ontario for the 10-yr period from Jan. 1, 1993 to Dec. 31, 2002. We also obtained all litigations (including disability weighted claims) handled by the Canadian Medical Protective Association during the same time period in which the Canadian Medical Protective Association experts considered the anesthesiologist cited to be at least partially responsible for the adverse event leading to the complaint. RESULTS: : In univariate analysis with the less than 51 age group as the reference category, the litigation rate ratio for the 51-64 age group was 1.14 (95% CI: 0.99-1.32) and for the 65 and older age group was 1.50 (95% CI: 1.14-1.97). Our analyses using disability weighted claims showed the 51-64 group to have 1.31 (95% CI: 0.95-1.80) and 65 and older group to have 1.94 (95% CI: 1.41-2.67) relative increase in disability compared to the less than 51 age group. CONCLUSIONS: : We found a higher frequency of litigation and a greater severity of injury in patients treated by anesthesiologists in the 65 and older group. The reasons for these findings should become an active field of research.

Single-dose dexamethasone reduces dynamic pain after total hip arthroplasty.

BACKGROUND: Preoperative glucocorticoids reduce postoperative nausea but may also improve analgesia and decrease opioid consumption. METHODS: Fifty consecutive patients undergoing elective, unilateral, primary total hip arthroplasty under spinal anesthesia with propofol sedation received in a randomized, double-blind, placebo-controlled manner either 40 mg of dexamethasone or saline placebo i.v. before the start of surgery. I.v. patient-controlled analgesia morphine, ibuprofen 400 mg p.o. q6 h and acetaminophen 650 mg p.o. q6 h were given for 48 h. Pain (0-10 numeric rating scale, NRS) at rest, side effects, and total cumulative patient-controlled analgesia morphine consumption were recorded q4 h for 48 h. Dynamic pain NRS score was recorded at 24 h. C-reactive protein levels were measured in a subgroup of 25 patients at 48 h. RESULTS: The intraoperative sedation requirement with propofol was significantly increased in the dexamethasone group (234.6 +/- 160.1 vs 138.8 +/- 122.7 mg, P = 0.02). Dynamic pain was greatly reduced in the dexamethasone group (NRS score: 2.7, 95% CI: 2.2-3.1 vs 6.8, 6.4-7.2; P < 0.0001). There was no significant effect on pain at rest or cumulative morphine consumption at any time. C-reactive protein levels at 48 h were markedly reduced by dexamethasone (52.4 mg/mL, 28.2-76.6 vs 194.2, 168.9-219.4; P < 0.0001). Seven patients in the control group, but only one in the dexamethasone group, were treated for nausea (P = 0.05). CONCLUSIONS: A single, preoperative i.v. dose of dexamethasone 40 mg has a prolonged suppressive effect on the inflammatory response and decreases dynamic pain 24 h after total hip arthroplasty.

Obturator versus femoral nerve block for analgesia after total knee arthroplasty.

BACKGROUND: Both femoral and obturator nerve blocks have been suggested to be useful in relieving pain after total knee arthroplasty (TKA). We sought to compare their efficacy. METHODS: Sixty patients undergoing elective unilateral TKA under spinal anesthesia received in a randomized, double-blind manner a femoral, obturator, or sham nerve block at the end of surgery. Blocks were performed using nerve stimulation and 20 mL bupivacaine 0.5% containing epinephrine 5 microg/mL. Patient-controlled IV analgesia with fentanyl, celecoxib 100 mg PO bid, and acetaminophen 650 mg PO every 6 h were started on arrival in the recovery room. Pain (0-10 numeric rating scale, NRS) at rest and with movement, analgesic use, and side effects were recorded for 48 h. Maximum knee flexion and total days in hospital were recorded as functional outcomes. RESULTS: There were no significant differences in the obturator block group and the control group in any outcome variable. With baseline pain scores subtracted, femoral block resulted in less pain at rest compared with control (NRS difference from baseline 2.1 +/- 0.4 sem vs 3.4 +/- 0.4, respectively; P = 0.02) and less pain with movement (NRS difference 2.6 +/- 0.6, 4.3 +/- 0.6, P = 0.05) at recovery room discharge. Neither block had a significant effect on opioid use, functional outcome, or side effects. Only one (5%) patient with femoral block developed obturator motor block. CONCLUSION: Femoral nerve blocks rarely block the obturator nerve. Single-injection femoral nerve block improved multimodal analgesia after spinal anesthesia for TKA, but this effect did not persist beyond the day of surgery. Obturator nerve block alone was of no benefit.

Blood gas measurements using the Bayer Rapid Point 405: are we basing our decisions on accurate data?

OBJECTIVE: Therapeutic decisions in the Operating Room (OR) are often made based solely upon results obtained from arterial blood gas machines. We evaluated how precise and accurate the results obtained from Bayer Rapid Point 405 (RP405) were vis-à-vis those of our blood gas laboratory and if they met the standards of the members of the anesthesia department. METHODS: About 3 ml of blood from an indwelling arterial catheter were drawn into a heparinized syringe (FIMS Portex Inc.) from each of 90 patients and immediately analyzed by two RP405 and the hospital's main blood gas machines (Instrumentation Laboratories GEM 3000). The remaining 2.8 ml of blood was used to measure Hematocrit and sent to the hospital's main biochemistry laboratory for electrolyte measurement using an indirect ion selective method (Roche Diagnostics Modular ISE Module). A survey was distributed to each of the 19 anesthesiologists at the Sir Mortimer B Davis Jewish General Hospital (JGH). Their opinions for accuracy and treatment thresholds for each of the 12 variables measured by the RP405 were sought. RESULTS: For all measured variables, including pH, pCO2, pO2, potassium and Hematocrit, the correlation between the measurements from the RP405 and the gold standard were all above 95.5% with a p < 0.001. The survey results demonstrate that the machine gives results that are accurate within the acceptability frame expected by our staff anesthesiologists. CONCLUSION: Anesthesiologists must be confident that the information they receive is accurate in the context of rapidly changing clinical status. Our results show that the RP405 analyzers produce reliable measurements.

Documentation on the anesthetic record: Correlation with clinically important variables.

PURPOSE: A survey was undertaken at a single Academic Health Sciences Centre to document the opinions of anesthesiologists regarding what variables are important to document on the anesthetic record. A subsequent chart review of anesthetic records was undertaken to determine the extent to which these anesthesiologists record the variables they consider important. METHODS: A survey form was mailed to all practicing staff anesthesiologists at the four adult McGill University affiliated hospitals. Anesthesiologists were asked to rank 23 preoperative and 33 intraoperative variables on a scale from 1-5: (1 = essential; 2 = important; 3 = useful; 4 = not important; 5 = excessive information). All variables considered by consensus < or = 2 (important to essential) were then assessed as to whether they were recorded on 60 charts randomly selected from each of the four teaching hospitals. Only anesthetic records completed by staff anesthesiologists were evaluated. RESULTS: Ninety percent (47/52) of survey forms were completed and returned. Preoperative variables considered most important to document included examination of the patient's airway and allergy status. Intraoperative variables considered most important for documentation were the patient's vital signs. The only variable to have been recorded on all the anesthetic records was the anesthesiologist's name. The allergy status was the most recorded preoperative variable (84% of charts). The recording rates of intraoperative variables ranged from 100% (anesthesiologist's name, start time of anesthesia) to 24% (estimated blood loss). CONCLUSION: McGill anesthesiologists consider many preoperative and intraoperative variables to be important to document on the anesthetic record. However, subsequent chart review indicated that many of these variables are recorded inconsistently. The transmission of anesthesia-related medical information might be improved if anesthesiologists recorded more consistently information they consider to be important.

Documentation on the anesthetic record: correlation with clinically important variables : [Documentation sur le dossier anesthésique : corrélation avec les variables cliniques importantes].

PURPOSE: A survey was undertaken at a single Academic Health Sciences Centre to document the opinions of anesthesiologists regarding what variables are important to document on the anesthetic record. A subsequent chart review of anesthetic records was undertaken to determine the extent to which these anesthesiologists record the variables they consider important. METHODS: A survey form was mailed to all practicing staff anesthesiologists at the four adult McGill University affiliated hospitals. Anesthesiologists were asked to rank 23 preoperative and 33 intraoperative variables on a scale from 1-5: (1 = essential; 2 = important; 3 = useful; 4 = not important; 5 = excessive information). All variables considered by consensus ≤ 2 (important to essential) were then assessed as to whether they were recorded on 60 charts randomly selected from each of the four teaching hospitals. Only anesthetic records completed by staff anesthesiologists were evaluated. RESULTS: Ninety percent (47/52) of survey forms were completed and returned. Preoperative variables considered most important to document included examination of the patient's airway and allergy status. Intraoperative variables considered most important for documentation were the patient's vital signs. The only variable to have been recorded on all the anesthetic records was the anesthesiologist's name. The allergy status was the most recorded preoperative variable (84% of charts). The recording rates of intraoperative variables ranged from 100% (anesthesiologist's name, start time of anesthesia) to 24% (estimated blood loss). CONCLUSION: McGill anesthesiologists consider many preoperative and intraoperative variables to be important to document on the anesthetic record. However, subsequent chart review indicated that many of these variables are recorded inconsistently. The transmission of anesthesia-related medical information might be improved if anesthesiologists recorded more consistently information they consider to be important. OBJECTIF: Une enquête a été menée à un Centre universitaire de sciences de la santé pour connaître les opinions des anesthésiologistes sur les variables jugées importantes à inscrire au dossier anesthésique. Une revue subséquente des dossiers anesthésiques a été réalisée pour vérifier si les anesthésiologistes enregistrent les variables qu'ils considèrent importantes. MéTHODE: Un formulaire d'enquête a été posté à tous les anesthésiologistes en exercice dans les quatre hôpitaux pour adultes affiliés à l'université McGill. On leur a demandé de coter 23 variables préopératoires et 33 peropératoires sur une échelle de 1-5: (1 = essentielle, 2 = importante, 3 = utile, 4 = non importante et 5 = surinformation). Toutes les variables reconnues par la majorité ≤ 2 (importante à essentielle) ont été ensuite vérifiées pour savoir si elles étaient enregistrées dans 60 dossiers choisis au hasard dans chacun des quatre hôpitaux d'enseignement. Seuls les dossiers anesthésiques remplis par des spécialistes en service ont été évalués. RéSULTATS: Des formulaires envoyés 90 % (47/52) ont été remplis et retournés. Les variables préopératoires considérées importantes comprenaient l'examen des voies aériennes du patient et la présence d'allergie. Les variables peropératoires prioritaires ont été les signes vitaux des patients. La seule variable enregistrée dans tous les dossiers a été le nom de l'anesthésiologiste. La présence d'allergie a été la variable préopératoire la plus souvent enregistrée (84 % des dossiers). Les taux d'enregistrement des variables peropératoires allait de 100 % (nom de l'anesthésiologiste, heure du début de l'anesthésie) à 24 % (perte sanguine estimée). CONCLUSION: Les anesthésiologistes de McGill considèrent que de nombreuses variables préopératoires et peropératoires sont importantes à noter au dossier anesthésique. Une revue subséquente des dossiers a indiqué que beaucoup de ces variables ne sont pas constamment inscrites. La transmission des informations médicales liées à l'anesthésie serait améliorée si les anesthésiologistes notaient plus régulièrement les variables qu'ils jugent les plus importantes.

Audio spectrum and sound pressure levels vary between pulse oximeters.

PURPOSE: The variable-pitch pulse oximeter is an important intraoperative patient monitor. Our ability to hear its auditory signal depends on its acoustical properties and our hearing. This study quantitatively describes the audio spectrum and sound pressure levels of the monitoring tones produced by five variable-pitch pulse oximeters. METHODS: We compared the Datex-Ohmeda Capnomac Ultima, Hewlett-Packard M1166A, Datex-Engstrom AS/3, Ohmeda Biox 3700, and Datex-Ohmeda 3800 oximeters. Three machines of each of the five models were assessed for sound pressure levels (using a precision sound level meter) and audio spectrum (using a hanning windowed fast Fourier trans-form of three beats at saturations of 99%, 90%, and 85%). RESULTS: The widest range of sound pressure levels was produced by the Hewlett-Packard M1166A (46.5 +/- 1.74 dB to 76.9 +/- 2.77 dB). The loudest model was the Datex-Engstrom AS/3 (89.2 +/- 5.36 dB). Three oximeters, when set to the lower ranges of their volume settings, were indistinguishable from background operating room noise. Each model produced sounds with different audio spectra. Although each model produced a fundamental tone with multiple harmonic overtones, the number of harmonics varied with each model; from three harmonic tones on the Hewlett-Packard M1166A, to 12 on the Ohmeda Biox 3700. There were variations between models, and individual machines of the same model with respect to the fundamental tone associated with a given saturation. CONCLUSION: There is considerable variance in the sound pressure and audio spectrum of commercially-available pulse oximeters. Further studies are warranted in order to establish standards.

Ketorolac analgesia for inguinal hernia repair is not improved by peripheral administration.

PURPOSE: It has been suggested that ketorolac, a non-steroidal anti-inflammatory drug (NSAID) available for parenteral use, may result in prolonged (24 hr) postoperative analgesia through a peripheral mechanism when added to local anesthetic infiltration. Our objective was to assess this effect by controlling for systemic absorption of the drug. METHODS: This randomized, double-blind trial studied 40 men undergoing elective inguinal hernia repair under spinal anesthesia. All patients received 19 mL of lidocaine 1% infiltrated in the operative field before incision. Patients were randomized into two groups of 20. The surgical site group received ketorolac 30 mg added to the lidocaine infiltration. In the control group, ketorolac 30 mg was injected subcutaneously in the contralateral abdominal wall. Numeric rating scores (0-10) of pain at rest and with movement were recorded at the time of discharge from the recovery room and at 24 hr postoperatively. Time to first analgesia, postoperative iv morphine use, total time in the recovery room, and total oral analgesic use in the first 24 hr were also compared. RESULTS: There were no significant differences between groups with respect to any of the measured variables. In both groups, pain scores were low at rest (1.9 +/- 1.4 vs 2.2 +/- 1.8, surgical site and systemic groups, respectively) and moderate with movement (5.3 +/- 2.2, 5.0 +/- 1.8) after anesthetic recovery. Pain scores were similar at 24 hr (1.1 +/- 1.3, 1.9 +/- 1.6 at rest; 5.7 +/- 2.0, 6.2 +/- 2.2 with movement). CONCLUSION: Adding ketorolac to lidocaine infiltration for hernia repair does not improve or prolong postoperative analgesia compared to systemic administration.

Intrapartum temperature changes following the intravenous crystalloid bolus for epidural analgesia.

OBJECTIVE: To assess the effect of the intravenous crystalloid bolus given before epidural analgesia on maternal temperature during labour. Multiple studies have demonstrated a hyperthermic trend in parturient women receiving epidural analgesia. This temperature rise may be affected by the pre-epidural intravenous crystalloid bolus. METHODS: Intrapartum oral temperatures were recorded in 40 singleton parturient women immediately before and after an intravenous bolus of Ringer's lactate solution (1L at room temperature [21 degrees C]) and at one hour after standardized insertion of an epidural catheter for analgesia. Exclusion criteria included antibiotic administration, chorioamnionitis, and initial maternal temperature above 37.5 degrees C. Group means were compared using the 2-tailed paired Student t test. RESULTS: There was no significant trend towards a decrease in maternal temperature after the crystalloid bolus (mean change -0.07 degree C, P = 0.33). Similarly, there was no initial trend towards an increased maternal temperature after epidural insertion (mean change + 0.02 degrees C, P > 0.7). Separate analyses using parity, body mass index, and bolus duration as covariates showed that these variables did not affect maternal temperature changes (P > or = 0.2). CONCLUSION: Our study indicates that intravenous infusion of a crystalloid bolus at room temperature before induction of epidural analgesia does not significantly decrease parturient temperature.

Desflurane does not accelerate recovery from operations of short duration: a practice audit.

PURPOSE: Desflurane, a newer inhalation anesthetic agent, has been promoted as a superior drug because patients will awaken sooner after anesthesia. This has only been proven in operations of long duration (i.e., more than one hour). We assessed our experience using desflurane in short out-patient surgery with a retrospective analysis of a single surgeon's elective laparoscopic cholecystectomy patients. METHODS: With Institutional consent, we performed a retrospective comparison of the postoperative recovery of patients who received desflurane/air/oxygen to historical control patients who received isoflurane/N2O/oxygen. RESULTS: Patient preoperative characteristics were similar in the two groups. Duration of surgery and the time from the end of surgery to patient leaving the operating room for the desflurane and isoflurane/N2O groups were (in minutes) 42.7 +/- 13.5 and 9.6 +/- 4.6 vs 47.2 +/- 15.1 and 8.5 +/- 4.1 respectively (P = NS). Total Aldrete scores upon presentation to the postanesthesia care unit (PACU) were 8.1 +/- 1.4 and 7.9 +/- 1.8 for the two groups respectively (P = NS). The percentage of patients who arrived in the PACU with consciousness scores of 2, 1, 0 for the desflurane and isoflurane/N2O groups were 20.4, 75.5, and 4.1 vs 14.6, 73.2 and 12.2 respectively (P = NS). Mean length of stay in the PACU for the two groups was 160 +/- 111 and 156 +/- 114 min (P = NS). CONCLUSION: Our results show that in short procedures the use of desflurane does not necessarily result in faster patient recovery or discharge from the PACU.

Acute vision impairment: does it affect an anesthesiologist's ability to intubate the trachea?

UNLABELLED: The result of impaired vision on an anesthesiologist's ability to intubate the trachea is unknown. We studied 12 attending staff anesthesiologists as they intubated 2 anesthesia mannequins (A and B) under 6 conditions. The conditions were: 1) usual vision, 2) central-vision loss with 20/500 bilaterally and a 24 degrees central scotoma, 3) peripheral-field loss with 20/20 bilaterally and a 7 degrees visual field, 4) peripheral-field loss with 20/20 bilaterally and a 3.5 degrees visual field, 5) central-vision loss with 20/200 bilaterally and a 12 degrees central scotoma, and 6) right eye ocular media opacity and 20/70 left eye usual acuity. The time to intubation was recorded by stopwatch from gripping the laryngoscope until the anesthesiologist signaled that the endotracheal tube was properly placed in the trachea. The mean +/- SD times to intubation for Mannequins A and B were 16.0 +/- 3.3, 31.9 +/- 10.4, 26.4 +/- 9.0, 26.4 +/- 7.7, 22.4 +/- 5.1, 25.5 +/- 16.9 and 16.6 +/- 6.6, 26.9 +/- 10.0, 21.4 +/- 9.2, 21.4 +/- 5.8, 21.5 +/- 7.7, 17.7 +/- 5.1 s for the 6 conditions, respectively. Multiple analysis of variance revealed a highly significant difference for the time to successful intubation between the anesthesiologists' usual vision and the vision-impaired conditions. There was a significant improvement in time to successful intubation from the first to subsequent intubation attempts. There were also more esophageal intubations in the vision-impaired conditions. This implies that anesthesiologists who develop acute severe vision impairment might have more difficulty intubating the trachea, which could initiate more critical incidents. The results of this study cannot be applied to anesthesiologists with chronic vision impairment. IMPLICATIONS: We found that acute severe vision impairment adversely affects the anesthesiologist's ability to intubate the trachea. This implies that anesthesiologists with acute onset of severe visual handicaps might have more difficulty intubating the trachea, which could initiate more critical incidents.