WEBVTT 1 00:00:06.740 --> 00:00:16.580 AIST Laboratories presents an anesthesia motion picture clinic in cooperation with the Department 2 00:00:16.580 --> 00:00:23.020 of Anesthesia at the University of Missouri on the techniques of anesthesia for minor 3 00:00:23.020 --> 00:00:27.700 surgery involving the oral cavity, pharynx, and larynx. 4 00:00:29.140 --> 00:00:33.800 First we shall demonstrate anesthesia in a 23-year-old volunteer. 5 00:00:35.160 --> 00:00:39.360 The second part of this film will show anesthesia for biopsy of the 6 00:00:39.360 --> 00:00:45.080 velecula. The features we shall emphasize are the vaporization of 7 00:00:45.080 --> 00:00:50.720 flueathane with air or with oxygen, a vaporizer which does not require 8 00:00:50.720 --> 00:00:57.680 compressed gases, continuous monitoring of respiration, a new airway technique 9 00:00:57.680 --> 00:01:02.880 involving intubation of both nasopharyngeal passages, and a monitored 10 00:01:02.880 --> 00:01:08.160 method of assisted respiration which ensures smooth anesthesia and guarantees 11 00:01:08.160 --> 00:01:14.540 adequate ventilation. The IV premedication was three-tenths milligram 12 00:01:14.540 --> 00:01:20.400 of atropine. The only anesthetic agent will be flueathane which is ideally 13 00:01:20.400 --> 00:01:27.820 suited to the ambulatory patient. A new monitoring valve called the Saturn will 14 00:01:27.820 --> 00:01:34.820 show the patient's breathing and also act as a non-rebreathing valve. The ambu 15 00:01:34.820 --> 00:01:39.700 bag and a small flueathane vaporizer complete the anesthetic equipment. 16 00:01:41.020 --> 00:01:43.360 Anesthesia will be induced with a mask. 17 00:01:48.420 --> 00:01:56.300 The vaporizer is set to deliver 1% flueathane which is usually well tolerated by the conscious patient. 18 00:02:04.360 --> 00:02:10.000 Note how the Saturn monitor deflects to and fro as the volunteer takes a deep breath. 19 00:02:10.680 --> 00:02:15.760 The right meter attached to the exhalation tube measures the tidal volume. 20 00:02:18.480 --> 00:02:25.040 One revolution of the small hand is one liter of ventilation. Frequent blood 21 00:02:25.040 --> 00:02:31.580 pressures are necessary to follow the plane of flueathane anesthesia. The 22 00:02:31.580 --> 00:02:37.040 initial pressure, 110 over 60, is plotted on the blackboard which will be used as 23 00:02:37.040 --> 00:02:49.920 the anesthesia chart. The temporal pulse is 80 per minute. Blood pressure falls 24 00:02:49.920 --> 00:02:55.760 with onset of surgical anesthesia. The systolic pressure has decreased 15 25 00:02:55.760 --> 00:03:02.340 millimeters of mercury and the patient has lost consciousness. After a peak 26 00:03:02.340 --> 00:03:09.840 concentration of 2.5, flueathane is reduced to 1.5%. Maximal assisting 27 00:03:09.840 --> 00:03:16.380 delivers more agent and hastens induction. The monitor signals the moment to assist 28 00:03:16.380 --> 00:03:23.260 inspiration. If expiration is obstructed, the right meter stops. It moves as soon as 29 00:03:23.260 --> 00:03:29.880 the obstruction is relieved. Two nasopharyngeal airways will provide a 30 00:03:29.880 --> 00:03:34.360 low-resistance connection to the anesthetic system and eliminate all of the 31 00:03:34.360 --> 00:03:41.060 dead space of the mask. This patient is ready for intubation after a four-minute 32 00:03:41.060 --> 00:03:47.080 induction. Before inserting the nasopharyngeal tubes, several maximally 33 00:03:47.080 --> 00:03:52.640 assisted inflations are delivered to produce a brief apnea. During this 34 00:03:52.640 --> 00:03:56.060 interval, intubation should be completed if possible. 35 00:04:05.260 --> 00:04:11.060 The lubricated nasopharyngeal tubes are carefully inserted. Their tips should rest 36 00:04:11.060 --> 00:04:17.440 beyond the tongue base but just short of the vocal cords. The nasopharyngeal tubes 37 00:04:17.440 --> 00:04:22.860 are connected into the anesthesia system. Their correct position is proved by the 38 00:04:22.860 --> 00:04:28.260 deflections of either the right meter or the Saturn monitor. Note that he 39 00:04:28.260 --> 00:04:32.740 breathes from the anesthesia system whether the mouth is open or closed. 40 00:04:33.660 --> 00:04:42.320 Spontaneous tidal volumes are 350 cc. Assisted tidal volumes are 800 cc. If 41 00:04:42.320 --> 00:04:48.160 inflations are excessive, the patient's tongue serves as a pop-off valve. The 42 00:04:48.160 --> 00:04:52.900 concentration of fluothane is reduced because the nasopharyngeal tubes are 43 00:04:53.100 --> 00:05:00.700 still tolerated during light anesthesia. The tubes and connector should be 44 00:05:00.700 --> 00:05:04.960 secured to prevent their moving in the pharynx and stimulating the patient 45 00:05:04.960 --> 00:05:06.600 during light anesthesia. 46 00:05:12.660 --> 00:05:19.860 With 7 tenths percent fluothane, the tidal volumes are now 300 cc. Because of 47 00:05:19.860 --> 00:05:25.020 the low dead space of the nasopharyngeal tubes, these spontaneous tidal volumes 48 00:05:25.020 --> 00:05:30.440 are adequate. However, ventilation will be assisted as often as possible. 49 00:05:32.620 --> 00:05:37.900 Maximally assisted inflations improve ventilation and help maintain stable 50 00:05:37.900 --> 00:05:45.220 anesthesia. During insertion of the bite block, note how the jaw muscles remain 51 00:05:45.220 --> 00:05:49.200 relaxed and provide an easy access to the oral cavity. 52 00:06:06.160 --> 00:06:11.300 The gauze pack is placed deep in the oral pharynx but with precautions not to 53 00:06:11.550 --> 00:06:20.530 include the rubber airways and obstruct respiration. After packing, the jaw may 54 00:06:20.530 --> 00:06:26.170 need to be repositioned to ensure that respiration is not obstructed. A free 55 00:06:26.170 --> 00:06:30.670 airway is indicated both on the monitoring valve and on the right meter. 56 00:06:31.710 --> 00:06:36.390 Airway management by this technique provides continuous visible observation 57 00:06:36.390 --> 00:06:41.390 of respiration and the means of inflating the lungs at will despite some 58 00:06:41.390 --> 00:06:46.470 leakage through the open mouth. Fluothane is still being vaporized with 59 00:06:46.470 --> 00:06:56.550 room air. The question arises as to the adequacy of oxygenation. To answer this 60 00:06:56.550 --> 00:07:02.110 question, blood is drawn from the femoral artery in a heparinized syringe and is 61 00:07:02.110 --> 00:07:06.650 immediately analyzed for oxygen saturation with the American optical 62 00:07:06.650 --> 00:07:14.210 oximeter. The sample shows 90% oxygen saturation, a safe but low normal value. 63 00:07:15.110 --> 00:07:19.990 If ventilation were further reduced, room air alone would not be sufficient. 64 00:07:20.670 --> 00:07:26.130 Therefore, whenever ventilation becomes marginal, oxygen should be added to the 65 00:07:26.130 --> 00:07:31.510 reservoir surrounding the intake of the vaporizer. Ventilation is maximally 66 00:07:31.510 --> 00:07:41.110 assisted with fluothane and oxygen. The blood pressure remains stable. Another 67 00:07:41.110 --> 00:07:46.750 arterial sample will show whether oxygenation has been improved. Note that 68 00:07:46.750 --> 00:07:51.670 arterial pressure displaces the plunger of the syringe, proving that the needle 69 00:07:51.670 --> 00:07:59.310 is not in the adjacent femoral vein. The arterial saturation will again be 70 00:07:59.530 --> 00:08:05.730 assisted with the oximeter. The saturation is 99%, demonstrating the advantage of 71 00:08:05.730 --> 00:08:11.850 adding oxygen to the vaporizer. As fluothane is turned off, emergence will be 72 00:08:11.850 --> 00:08:20.430 accelerated by hyperventilation. Tidal volumes are 800 cc. During 20 minutes of 73 00:08:20.430 --> 00:08:26.030 anesthesia, the blood pressure stabilized at 100 over 60 millimeters of mercury and 74 00:08:26.030 --> 00:08:32.810 a pulse at 80 per minute. With recovery, the blood pressure returns to the 75 00:08:32.810 --> 00:08:39.170 preoperative level. Observe that the nasopharyngeal tubes are still well 76 00:08:39.170 --> 00:08:48.310 tolerated as anesthesia progressively lightens. The pharyngeal packing is 77 00:08:48.510 --> 00:08:59.610 removed. Then the tape securing the nasopharyngeal tubes comes off. The 78 00:08:59.610 --> 00:09:03.650 return of muscle tone in the pharynx will prevent collapse and obstruction of the 79 00:09:03.650 --> 00:09:13.910 airway as the nasopharyngeal tubes are withdrawn. The bite block is no longer 80 00:09:13.910 --> 00:09:22.150 necessary. For an optimum airway, the jaw is extended. If respiration is free and 81 00:09:22.150 --> 00:09:29.830 unimpeded, one can feel exhalation. Breathing remains adequate. His eyes now 82 00:09:29.830 --> 00:09:37.290 diverge, indicating that he will awaken shortly. This technique is safe and 83 00:09:37.290 --> 00:09:41.370 efficient because spontaneous ventilation can be monitored continually 84 00:09:41.370 --> 00:09:46.870 and assisted as needed. The anesthetic apparatus does not encumber the operative 85 00:09:46.870 --> 00:09:54.490 field. The patient will promptly respond and recover his protective reflexes. 86 00:10:01.550 --> 00:10:05.790 Recovery time is rapid because light planes of anesthesia are adequate, 87 00:10:05.790 --> 00:10:14.030 lighter than required if a tracheal tube were used. Within minutes, the patient 88 00:10:14.030 --> 00:10:22.290 awakens without the confused groggy state often seen after barbiturates. He 89 00:10:22.290 --> 00:10:27.170 will be able to sit up, get up, and walk away without the need for close 90 00:10:27.170 --> 00:10:33.090 observance during the recovery period. Nausea has not been noted. He is lucid, 91 00:10:33.090 --> 00:10:38.390 knows time and place, and can walk without help. Assisted fluothane anesthesia using 92 00:10:38.390 --> 00:10:43.390 simple equipment and bilateral nasopharyngeal tubes offers better and safer 93 00:10:43.390 --> 00:10:47.850 general anesthesia for oral procedures than the intravenous techniques which 94 00:10:47.850 --> 00:10:53.990 neglect the means to prevent respiratory depression and hypoxia. This technique is 95 00:10:53.990 --> 00:10:58.810 also suitable for any procedure requiring access to the larynx as in the next 96 00:10:58.810 --> 00:11:03.790 patient, a 74-year-old male scheduled for biopsy of a lesion on his right 97 00:11:04.890 --> 00:11:09.850 velecula. Following induction with fluothane, the nasopharyngeal tubes were 98 00:11:09.850 --> 00:11:15.030 inserted. He has been anesthetized for four minutes. He is breathing 99 00:11:15.030 --> 00:11:20.910 spontaneously. Spontaneous tidal volumes of 200 cc are just adequate with a rate 100 00:11:20.910 --> 00:11:26.270 of 26 per minute because of the reduced dead space. Preserving adequate 101 00:11:26.270 --> 00:11:30.910 spontaneous respiration is essential for the open insufflation method to be used 102 00:11:30.910 --> 00:11:35.870 here. Compressing the bag will deliver the anesthetic vapor into the pharynx, 103 00:11:36.290 --> 00:11:40.450 but it is the patient's own inspiration that must carry it into his lungs. 104 00:11:41.430 --> 00:11:45.190 Therefore, the chest will be observed and bag compression will be timed 105 00:11:45.190 --> 00:11:50.950 synchronously with each spontaneous inspiration. Before inserting the lynch 106 00:11:50.950 --> 00:11:55.770 tongue blade, his reaction is tested by large inflations which he accepts 107 00:11:55.770 --> 00:12:00.330 without bucking and therefore is judged to be ready to tolerate laryngoscopy. 108 00:12:02.930 --> 00:12:07.870 Vigorous assisted respiration should not be continued to produce apnea which 109 00:12:07.870 --> 00:12:11.730 would complicate the maintenance of anesthesia by the insufflation method. 110 00:12:13.510 --> 00:12:19.090 The lynch suspension apparatus is in place. He tolerates the adjustments and 111 00:12:19.310 --> 00:12:27.030 elevation of the blade well. Fluothane anesthesia is maintained by intermittent 112 00:12:27.030 --> 00:12:32.250 delivery of vapor into his pharynx by bag compression, synchronous with spontaneous 113 00:12:32.250 --> 00:12:43.390 inspiration. Blood pressure is 110 over 70. Here is a close-up view of the field 114 00:12:43.390 --> 00:12:48.350 of examination. The tongue blade of the suspension apparatus is seen at the top, 115 00:12:48.350 --> 00:12:53.670 providing a wide exposure of the hypopharynx and the posterior laryngeal structures. 116 00:12:55.930 --> 00:12:59.970 Please observe that there is minimal movement of the laryngeal structures 117 00:12:59.970 --> 00:13:06.350 with spontaneous respiration. Near the middle of the frame, the two clamps of 118 00:13:06.350 --> 00:13:11.210 the apparatus are secured to the upper molars to ensure stability of the patient's head. 119 00:13:11.990 --> 00:13:16.030 The nasopharyngeal tube connections are seen in the lower part of the frame. 120 00:13:17.210 --> 00:13:24.050 The surgeon has a wide access to the entire hypopharynx without the encumbrance of an endotracheal 121 00:13:24.050 --> 00:13:29.710 tube. Surgical manipulations do not interfere with the maintenance of inhalation anesthesia 122 00:13:29.710 --> 00:13:37.950 and ventilation. During the entire examination and repeated biopsies, anesthesia is maintained 123 00:13:37.950 --> 00:13:44.550 by intermittent insufflation of 1.5 to 2% fluothane in rhythm with the patient's breathing. 124 00:13:46.070 --> 00:13:52.190 There is no need to hurry the surgeon as in other methods which utilize apneic oxygenation. 125 00:13:52.790 --> 00:13:58.610 He can be sure all bleeding is controlled and that no blood has been aspirated into the lungs. 126 00:14:00.630 --> 00:14:06.770 This technique of open insufflation, unlike the older ether insufflation for tonsillectomy, 127 00:14:07.390 --> 00:14:12.150 utilizes an intermittent high flow of anesthetic vapor into the pharynx with 128 00:14:12.150 --> 00:14:18.470 volumes which exceed the tidal volumes. This excess prevents dilution of the patient's 129 00:14:18.470 --> 00:14:24.210 inspiration with room air. The result is an improved control of the level of anesthesia 130 00:14:24.210 --> 00:14:32.390 and the elimination of all the dead space above the larynx. The biopsy site is dry and the procedure 131 00:14:32.390 --> 00:14:38.450 is completed. The Lynch apparatus is removed and anesthesia will be terminated. 132 00:14:42.510 --> 00:14:49.590 Emergence is hastened by hyperventilation with room air. Rapid recovery is another 133 00:14:49.590 --> 00:14:57.250 advantage of this method with fluothane over ether insufflation. Removal of the 134 00:14:57.250 --> 00:15:07.530 nasopharyngeal tubes provokes a cough which is desirable. Fluothane air insufflation with 135 00:15:07.530 --> 00:15:13.170 nasopharyngeal incubation and assisted respiration provides a smooth and safe 136 00:15:13.170 --> 00:15:21.270 anesthetic for examination and biopsy of the larynx. In summary, we believe that inhalation 137 00:15:21.270 --> 00:15:27.950 anesthesia for minor surgical procedures upon the oral and laryngeal airway is safer and more 138 00:15:27.950 --> 00:15:36.690 effective than other techniques. The four cardinal principles are, one, atropine to dry secretions 139 00:15:36.690 --> 00:15:44.810 and partially block the cardiac vagus. Two, fluothane in concentrations of one to two percent. 140 00:15:46.490 --> 00:15:52.830 Three, management of the airway by incubation of both nostrils with soft catheters which provide 141 00:15:52.830 --> 00:16:00.490 a resistance of one half that of a tracheal tube and which also permit lighter anesthesia. And 142 00:16:00.490 --> 00:16:06.270 finally, but of crucial importance, the continual application of the new practice of maximally 143 00:16:06.270 --> 00:16:12.150 assisted ventilation by which the patient regulates respiration and the anesthetist 144 00:16:12.150 --> 00:16:16.970 provides the power to move the anesthetic vapor and oxygen to the lungs.