[False low oximetry reading caused by patent blue vital dye during breast surgery]. / Falsa desaturación provocada por colorante durante la cirugía de mama.

Patent blue vital (patent blue V; Laboratoire Guerbet, France) is used to identify the sentinel node during surgery for invasive breast cancer. Detecting the sentinel node that first drains the primary tumor reduces the need for total breast and wide axillary node removal, with the problems that such radical surgery involves. Like other dyes, patent blue V can interfere with accurate pulse oximeter reading, leading to underestimation of real values. We report the case of a 31-year-old woman who underwent lumpectomy and removal of the sentinel node. After intradermal injection of patent blue V dye into the left breast (100 mg administered because the sentinel node was difficult to locate) a drop in peripheral oxyhemoglobin saturation from 99% to 93% was detected by the pulse oximeter. When arterial blood gas analysis showed normal values and other causes were ruled out, the diagnosis was false low oximetry reading due to patent blue V dye.

[The creation of the first anesthesiology service in Spain (Hospital de la Santa Cruz y San Pablo, Barcelona 1941)]. / En torno a la creación del primer Servicio de Anestesiología en España (Hospital de la Santa Cruz y San Pablo, Barcelona 1941).

On the sixtieth anniversary of the founding of the first Spanish anesthesia department, we review factors that led to its creation and its early development. Hospital de la Santa Cruz y San Pablo in Barcelona was the place where the service was established for several reasons. The first was the growing need for anesthesia to be administered by specialized physicians able to handle problems developing during and after surgery. The second was the presence of a prestigious surgeon, Dr. Juan Soler Juliá, who perceived the need, alongside the only physician in Spain who was completely dedicated to anesthesiology, Dr. José Miguel Martínez. Finally, the fact that professional anesthesiology allowed a physician to earn a decent income triggered interest in the specialty among physicians.

Comparison of auditory evoked potentials and the A-line ARX Index for monitoring the hypnotic level during sevoflurane and propofol induction.

BACKGROUND: Extraction of the middle latency auditory evoked potentials (AEP) by an auto regressive model with exogenous input (ARX) enables extraction of the AEP within 1.7 s. In this way, the depth of hypnosis can be monitored at almost real-time. However, the identification and the interpretation of the appropriate signals of the AEP could be difficult to perform during the anesthesia procedure. This problem was addressed by defining an index which reflected the peak amplitudes and latencies of the AEP, developed to improve the clinical interpretation of the AEP. This index was defined as the A-line Arx Index (AAI). METHODS: The AEP and AAI were compared with the Modified Observers Assessment of Alertness and Sedation Scale (MOAAS) in 24 patients scheduled for cardiac surgery, anesthetized with propofol or sevoflurane. RESULTS: When comparing the AEP peak latencies and amplitudes and the AAI, measured at MOAAS level 5 and level 1, significant differences were achieved. (mean(SD) Nb latency: MOAAS 5 51.1 (7.3) ms vs. MOAAS 1: 68.6 (8.1) ms; AAI: MOAAS 5 74.9 (13.3) vs. MOAAS 1 20.7 (4.7)). Among the recorded parameters, the AAI was the best predictor of the awake/anesthetized states. CONCLUSION: We conclude that both the AAI values and the AEP peak latencies and amplitudes correlated well with the MOAAS levels 5 (awake) and 1 (anesthetized).

[Comparison of an auditory evoked potentials index and a bispectral index versus clinical signs for determining the depth of anesthesia produced by propofol or sevoflurane]. / Comparación de la efectividad de un índice de potenciales evocados auditivos y un índice biespectral con los signos clínicos en la determinación de la profundidad hipnótica durante anestesia con propofol o sevoflurano.

OBJECTIVES: To evaluate an anesthetic depth index (ADI) obtained from auditory evoked potentials and a bispectral EEG index (BIS) in comparison with clinical assessment of anesthetic depth using the modified observer's assessment of awareness/sedation scale (MOAA/SS), for induction of anesthesia with propofol or sevoflurane as the only agent. PATIENTS AND METHODS: The ADI and BIS were recorded simultaneously in this prospective study and compared to the MOAA/SS during the anesthetic induction of 26 adults undergoing elective heart surgery. Assignment of patients to two groups was random. Group A (n = 13) patients were induced with propofol (target dose 5 micrograms.ml-1 in 5 min). Induction in group B (n = 13) was with sevoflurane (8% tidal volume). A scheme of awake-sleeping-awake-sleeping was followed. The means of the two indexes were compared (Mann-Whitney test) one minute before the patient slept (awake) and one minute later (sleeping), and the evolution of the indexes was compared during awake/sleep and sleep/awake phase changes and while the patients were in a stable sleep phase. The sensitivity and specificity of each index was analyzed in function of the MOAA/SS. We also analyzed the time elapsing from the moment the patient fell asleep (MOAA/SS 2) until the two indexes reached published reference values (ADI = 38, BIS = 60). RESULTS: After induction with propofol (group A) the ADI fell to 29.2 +/- 11.7 and the BIS fell to 63.5 +/- 13.4. After induction with sevoflurane (group B) the ADI fell to 33.8 +/- 14.9 and the BIS to 66.8 +/- 15. The ADI value that best discriminated between arousal and sleeping (sensitivity 100%) was 38; the BIS value that best discriminated was 60. The responses to sound in decibels (dB) during "awake/sleeping" and "sleeping/awake" phases were, respectively, -3.8 dB and -4.5 dB for the ADI and -1.5 dB and -0.8 dB for the BIS. With the patient in stable sleep, response to the two indexes was at -0.79 dB. In group A, the ADI detected MOAA/SS 2 significantly earlier (ADI 13.1 +/- 30 s; BIS 56 +/- 36 s; p < 0.05). No patient reported remembering the study period. CONCLUSIONS: Monitoring anesthetic depth with the ADI or BIS was technically easy and effective for detecting whether patients were awake or sleeping. The ADI response was faster and identified awake/sleeping and sleeping/awake phase changes better than did the BIS.

[Impossibility of intubation due to angioedema secondary to an angiotensin-converting enzyme inhibitor]. / Imposibilidad de intubación por angioedema secundario a IECA.

Angioedema secondary to treatment of one year's duration with angiotensin converting enzyme inhibitor (ACEI) (lisinopril) in a 56-year-old man scheduled for elective cardiac surgery led unexpectedly to impossible intubation. Surgical access (tracheostomy) was required when airway control was threatened. We review the clinical course, etiology and treatment of angioedema secondary to ACEI therapy. This is a life threatening complication which, though rare, is becoming increasingly frequent with increased use of such drugs.

[Air-convection heater for abdominal surgery. Study of the relation between surgical time and the efficacy of body temperature maintenance]. / Calentador por convección de aire en cirugía abdominal. Estudio de la relación tiempo quirúrgico-eficacia del mantenimiento de la temperatura corporal.

OBJECTIVES: 1) To quantify the efficacy of forced air warming for maintaining body temperature during general anesthesia of adults, and 2) to study the relation between the duration of surgery and the level of thermal protection provided by the device used. PATIENTS AND METHODS: We studied 30 adult patients of both sexes who were scheduled for abdominal surgery involving laparotomy. After three patients were excluded because surgery was unfeasible, the remaining 27 were allocated randomly to a control group (n = 14) or a group (n = 13) to be warmed by a Bair Hugger (Augustine Medical Inc.) heater. Esophageal temperature was checked every 30 min by one probe of a modular thermometric channel (Mon-a-therm) 6510 Mallincrodt, while ambient temperature was monitored by the second probe. RESULTS: Significant differences in esophageal temperature were observed between the two groups from the second hour after start of surgery, and the differences increased over time. Differences were observed at the end of surgery (Bair group: 36.4 +/- 0.5 degrees C; control group: 34.7 +/- 1.1 degrees C) and upon admission to the intensive care recovery unit (Biar group: 36.3 +/- 0.6 degrees C; control 34.8 +/- 1.0 degrees C) (p < 0.0001). CONCLUSIONS: The Bair Hugger heater is effective during abdominal operations lasting two or more hours. The device not only prevented hypothermia from deepening during surgery, but also reversed hypothermia in spite of being used after anesthetic induction and in spite of the loss of heat produced by secondary vasodilation.

[María Oliveras: pioneer of neuroanesthesia in Catalonia]. / María Oliveras: pionera de la neuroanestesia en Cataluña.

María Oliveras Collelmir (1910) was the first woman to practice anesthesiology in Catalonia and one of the first physicians to receive formal training in the specialty at the important Nuffield Department of Anaesthetics in Oxford. She pioneerèd the use of general anesthesia with tracheal intubation for neurosurgery. This article relates how Dr. Oliveras introduced general anesthesia with endotracheal intubation for neurosurgery in Catalonia and pays well-deserved homage to this enterprising woman, who overcame family obstacles and social prejudices of the time to become the first female anesthesiologist in Catalonia.

Continuous infusion is superior to bolus doses with thoracic paravertebral blocks after thoracotomies.

OBJECTIVES: This study was designed to determine whether a continuous thoracic paravertebral infusion of bupivacaine (continuous TPVI) offers a higher quality of analgesia than a bolus regimen after thoracotomy. DESIGN: A prospective and randomized study. SETTING: It was conducted by an anesthesiology and pain clinic department in a university hospital. PARTICIPANTS: Thirty patients were included in this study. INTERVENTIONS: As postoperative analgesia, the patients received either 20 mL of 0.375% bupivacaine every 6 hours (n = 15; bolus group), or a loading dose of 15 mL of 0.375% bupivacaine, plus an infusion of 5 mL of 0.25% bupivacaine every hour (n = 15; infusion group). MEASUREMENTS AND MAIN RESULTS: Pain intensity was assessed at rest and on movement (coughing) at 0, 1, 4, 10, 20, and 48 hours by means of the visual analog scale. The need for additional rescue analgesia, bupivacaine plasma concentration in the infusion group, blockade level (pinprick), and vital signs were also recorded. There were no significant differences regarding the additional rescue analgesia, vital signs, and pinprick level. However, the pain scores were significantly higher in the bolus group at rest and on movement (p < 0.01). The bupivacaine plasma concentration was low with a Cmax of 1.841 +/- 0.20 micrograms/mL at 15 hours. No systemic toxicity or other side effects were seen. CONCLUSION: Results suggest that continuous TPVI provides better pain control than the bolus regimen after this kind of surgery.

[Anesthesia in Kearns-Sayre syndrome (mitochondrial myopathy)]. / Anestesia en el síndrome de Kearns-Sayre (miopatía mitocondrial).

We report the case of a 27-year-old woman with a history of Kearns-Sayre syndrome and a double mitral lesion who underwent surgery without complications. Anesthetic induction was achieved with propofol and fentanyl, and maintenance was with nitrous oxide and oxygen through a face mask. There were no instances of O2 desaturation or hemodynamic alterations. The postoperative period transpired without adverse events and the patient was released 24 h after surgery. The management of anesthesia in this rare mitochondrial disease is described, and anesthetic alternatives are discussed as depending on clinical findings that can occur in the context of these syndromes.

[Anesthesia for thoracoscopy]. / Anestesia en la toracoscopia.

The thoracoscopy is used both for diagnosis and treatment of pleural and lung diseases. We describe our experience in managing anesthesia for such procedures, the number of which is increasing thanks to technical advances. We review 82 thoracoscopic procedures, 48 of which were video assisted. Sixty-two were performed under balanced general anesthesia (GA) with isoflurane, fentanyl and atracurium. Local anesthesia (LA) with fractionated doses of propofol and fentanyl was used in 20 cases. The mean age of patients receiving LA (63 +/- 17 years) was significantly greater (p < 0.05) than those receiving GA (49 +/- 13 years). ASA IV patients were given LA and sedation. Selective bronchial intubation was performed in 46 cases. Complications during surgery were severe hypoxemia (SpO2 < 85%) requiring suspension of selective lung ventilation in 8 cases, moderate hypoxemia (spO2 < 90% and > 85%) in 1 case, coughing in 3 cases and agitation in 1 case. Video-thoracoscopy is a safe technique that is less invasive than conventional thoracotomy. The number of applications is increasing, although its future place in thoracic surgery must still be determined.

[Analgesia of postoperative pain in ambulatory surgery]. / Analgesia del dolor postoperatorio en cirugía ambulatoria.

Although the role of outpatient surgery has become increasingly important in the campaign to reduce waiting lists and health care costs, careful control and treatment of postoperative pain too often receives slight attention. Pain control after surgery must produce high quality analgesia without lengthening the hospital stay or increasing the risk of complications. The risk of side effects must be low, the safety margin wide and administration simple. Anesthesiologists must therefore take preventive measures as well as apply techniques during and after surgery that diminish the intensity of pain and the incidence of nausea or vomiting. Drugs that act in the short term and have few side effects, regional anesthesia (depending on type of operation), non-opioid analgesics and balanced analgesia seem to give good quality control of pain after outpatient surgery.

[Obstetric analgesia using continuous epidural perfusion of bupivacaine, adrenaline, and fentanyl]. / Analgesia obstétrica mediante perfusión epidural continua de bupivacaína, adrenalina y fentanilo.

OBJECTIVES: To determine the efficacy and complications of continuous epidural perfusion of bupivacaine, adrenaline and fentanyl in the relief of pain during first and second stage labour during vaginal birth. PATIENTS AND METHODS: Between January 1990 and March 1993 we used continuous epidural perfusion for control of pain during labor in 1307 women. The solution administered through an epidural catheter and maintained until expulsion was one 10 ml bolus of bupivacaine 0.25% with adrenaline 1:200,000 and fentanyl 25 micrograms followed by continuous perfusion of bupivacaine 0.0625% with adrenaline 1:200,000 and fentanyl 2 micrograms/ml at an infusion rate of 12 ml/h. When analgesia was insufficient, a bolus of local anesthetic was administered or a pudendal block was carried out. RESULTS: Ninety-two percent of the birthing women reported good analgesic effect during the first stage; for 7% the effect was fair and for 0.55% it was poor. During the second stage 88% reported satisfactory analgesia, and 8% fair or poor. Assessment was not possible for the remaining women, who underwent cesarean sections. Complications were few and easily controllable. CONCLUSIONS: Maintenance of epidural perfusion with 0.0625% bupivacaine with adrenaline 1:200,000 and fentanyl 2 micrograms/ml provides sufficient analgesia during all stages of childbirth.