B - $36 bilateral acupuncture (n = 33). $36 (Zusanli), the 36th point on the stomac meridian, lies three. Chinese body-inches (ts'un) below the inferolateral.
1224 lidocaine spray to the oropharynx and 2% lidocaine administered through the bronchoscope. Sedation was accomplished using increments of midazolam (1.5 mg total) and fentanyl (50 ~g total). During the procedure, which involved examination of the bronchial anastomosis and selected biopsies, dilute epinephrine (0.4 ~tg. ml -I) was instilled via the bronchoscope to reduce airway oedema. Despite the use of minimal sedation, towards the end of the procedure the patient unexpectedly displayed clinical signs of hypercarbia, including confusion and somnolence, and later, diminished responsiveness. Hypercarbia was confirmed by blood gas analysis (PaCO2 = 57 mmHg, PaD2 = 173 mmHg). In order to improve alveolar ventilation the trachea was then intubated (without drugs) and the lungs were ventilated (manually, and later mechanically), but without an improvement in the hypercarbia (PCO2 values: 68, 74 and 83 mmHg). It was hypothesized that the patient's emphysematous, highly compliant native lung was being preferentially ventilated over her less compliant, oedematous (from bronchoscope trauma) transplanted lung, resulting in a large dead space. More epinephrine to the transplanted lung did not improve the situation. In an effort to redirect gas flow to the transplanted lung, the trachea was reintubated with a size 7.5 mm Univent| endotracheal tube, which features an integral bronchial blocker, which can be placed in either bronchus under fibreoptic guidance. J-3 Following the introduction of the blocker in the left bronchus, mechanized ventilation was maintained. Her arterial PCO2, quickly decreased to 63 mmHg, and eventually 54 mmHg. The trachea was extubated uneventfully the next day. Since the description of the Univent| tube by InDue ! in 1982, it has been shown to be useful in procedures such as aortic aneurysm repair, 4 bronchopleural fistula repair, 5 lung transplantation 6 and a variety of other procedures requiring one-lung ventilation. 2,3 This report shows how it may also be useful in improving alveolar ventilation in some situations. John Doyle Mr) PhO FRCPC The Toronto Hospital (General Division) Toronto, Ontario, M5G 2C4 D.
REFERENCES
1 InDue H, Shotsu A, Ogawa J, et al. New device for one-
lung anesthesia: endotraeheal tube with moveable blocker. Thorac Cardiovasc Surg 1982; 83: 940-1. 2 Karwande S. A new tube for single lung ventilation. Chest 1987; 92: 761-3. 3 Kamaya H, Krishna P. New endotracheal tube (Univent| tube) for selective blockade of one lung. Anesthesiology 1985; 63: 342-3.
CANADIAN JOURNAL OF A N A E S T H E S I A
4 Badner N. Lung isolation during aneurysmectomy. J Car-
diothorac Vasc Anesth 1991; 5: 302. 5 Herenstein R, Russo 3, Moonka N. Management of one-
lung anesthesia in an anticoagulated patient. Anesth Analg 1988; 6:1190-22. 6 Scheller M, Kreit J,, Smith C. Airway management during anesthesia for double-lung transplantation using a singlelumen endotracheal tube with an enclosed bronchial blocker. J Cardiothorac Vasc Anesth 1992, 6: 204-7.
Acupuncture accelerates recoveryfrom general anaesthesia To the Editor: Acupuncture is a widespread technique to produce analgesia or sedation. ~ Indeed, many "resuscitation" points are traditionally indicated for the symptomatic treatment of "loss of consciousness": 2 for example, K1 (Yongquan), the first point on the kidney meridian, which lies between the anterior one-third and the posterior two-thirds of the midline of the sole of the foot.2 No study has, to our knowledge, evaluated the efficacy of either acupuncture or plantar stimulation (e.g., for newborns with minor asphyxia at birth 3) in "resuscitative" practice. We designed a trial to evaluate the effect of KI acupuncture on extubation time after general anaesthesia. Informed consent was obtained from 99 ASA I or II adult (21-77 yr) patients, who underwent microdiscectomy between May and December 1992. Patients had no sensory or motor impairment and were not receiving sedative or narcotic drugs. Anaesthesia was induced with fentanyl and thiopentone; vecuronium provided neuromuscular relaxation for orotracheal intubation. Anaesthesia was maintained with N20 70% and isoflurane 0.5-2% in oxygen and ETCO2 was 30-35 mmHg. No intraoperative narcotics, sedatives or muscle relaxants were administered. At the end of surgery neostigmine provided reversal of neuromuscular block. The inspired isoflurane concentration which provided intraoperative analgesia was maintained until arrival in the recovery room, (TO) where the lungs were ventilated with oxygen and the patients were randomly assigned to one of the three groups: A - K1 bilateral acupuncture (n = 33); B - $36 bilateral acupuncture (n = 33). $36 (Zusanli), the 36th point on the stomac meridian, lies three Chinese body-inches (ts'un) below the inferolateral margin of the rotula, 1 tsktn laterally from the anterior cresta tibialis. It is widely employed for analgesia and sedation. 1.2
CORRESPONDENCE C - No acupuncture (n = 33). The patients received no sensory stimulation, but the needles (0.3 mm diameter single-use acupuncture needles, at a depth of 2 cm) were continuously stimulated manually. Groups were homogeneous as to sex, age, body weight, preanaesthetic mean arterial pressure (MAP) and heart rate (HR) and duration of surgery. The extubation of the trachea (time = Te) was decided by the single anaesthetist in charge of the patients, who was not involved in the study and not aware of its goals. The T0-Te difference among the three groups (one-way analysis of variance: P < 0.001), being was respectively 8.41 + 4.5 (min + SD) for Group A, 14.8 + 4.7 for Group B, and 14.75 -t- 5.5 for Group C. Group A differs from Groups B and C (Student-Newman-Keuls test: P < 0.005). Only one patient in Group A and two in Group B exhibited leg movements which could have been related to painful stimulation by the needles. Hence, we argue that pain does not explain the "arousal" effect of K 1. Despite some methodological problems these data suggest further study on the "analeptic" effect of acupuncture. Marco Gemma MD Monica Bricchi MD Alberto Giannini MD Barbara Coffano MD Laura Grandi MD Pierettore Quirico Mo Ist. Neurologico "C. Besta~ Div. Neurorianimazione Via Celoria I 1 20133 Milano - Italia REFERENCES 1 Pomeranz B, Stux G. (Eds.). ScientificBases of Acupuncture. New York: Springer-Vedag, 1989. 2 Essentials of Chinese Acupuncture. Beijing:Foreign languages Press, 1980. 3 Safar P, Bircher NG (Eds.). Cardiopulmonary Cerebral Resuscitation. Philadelphia: W.B. Saunders, 1988.
Polamedco endotracheal tubes To the Editor: Thank you for your very fair portrayal of a problem with the Polamedco endotracheal tube reported by Dr. McCaskil in your June issue. I have enclosed a sample of Polamedco's redesigned tube that now includes a stop to limit the connector travel. When contacting the stop, only 0.3 inches of tube can protrude from the connector, not
1225
Downstop
"7~ g e
Figure TABLE Forceto moveconnectorpast end flangeor downstop Tube size (ram)
Pull off force (lbs)
Move down force (lbs)
4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0
23.5 29.5 26.7 27.8 37.2 31.7 27.1 25.1 20.2 17.4 19.3
26.I 30.8 22.1 23.4 35.1 30.0 21.7 22.8 18.8 18.1 16.6
enough to interfere with the fLsh-mouth valve of the Laerdal bag. An additional stop (flange) is placed at the proximal end of the tube to increase the force needed for connector pull-off (Figure). The connector will still swivel on the tube and allow downward adjustment of approximately 1 inch. The attached Table shows the force in pounds required for the connector to override the stops. We think you will agree that these forces are more than adequate in even severe usage. M. Schneider Chief Engineer Polamedco
