British Journal of Anaesthesia 1991; 67: 779-780
P6 ACUPUNCTURE AND POSTOPERATIVE VOMITING AFTER TONSILLECTOMY IN CHILDREN S. M. YENTIS AND B. BISSONNETTE
After approval by the Human Subjects Review Committee, we obtained informed written consent from the parents of 45 children of ASA physical status I or II presenting for elective tonsillectomy. The children were allocated randomly to two groups, the sizes being determined by power analysis assuming a value for a of 0.05, |3 of 0.2, control incidence of vomiting of 80 % and postacupuncture incidence of 40 %. No premedication was given. Anaesthesia was induced with i.v. thiopentone 5 mg kg"1, atropine 0.02 mg kg"1, and suxamethonium 1.5 mgkg"1. Manual inflation of the lungs (taking care not to inflate the stomach) was followed by tracheal intubation and spontaneous ventilation with 66% nitrous oxide and KEY WORDS 1.5-2.0% isoflurane in oxygen. The children in Anaesthesia: paediatric. Anaesthetic techniques: acupuncone group received acupuncture at the P6 point ture. Surgery: tonsillectomy. paediatric Vomiting:incidence on the left side with 5 min manual stimulation, using sterile, disposable 0.2-mm diameter acuVomiting is common after paediatric tonsil- puncture needles. The acupuncture was adlectomy, with a reported incidence of up to 81 % ministered by one investigator (S. Y.) immediately [1]. Stimulation of the P6 acupuncture point has after tracheal intubation and before the start of been shown to reduce nausea and vomiting surgery. significantly in adults undergoing gynaecological I.m. codeine 1.5 mgkg"1 was administered to procedures [2, 3] and chemotherapy [4], and has all patients at the end of surgery. Estimated fluid no side effects [2]. This point ("Neiguan") is deficit and maintenance requirements were resituated two "Chinese inches" (two widths of the placed with i.v. Ringer's lactate solution. After interphalangeal joint of the patient's thumb) operation, i.m. dimenhydrinate 1.0 mgkg"1 was proximal to the distal skin crease of the wrist [2]. available if the incidence of vomiting exceeded Children often respond well to acupuncture in three episodes during any 1-h period. Further general, and arc included in the group termed i.m. codeine 1.0 mgkg"1 or oral paracetamol "strong reactors" [5]. P6 acupuncture and 10 mg kg"1 was available on the ward as required postoperative vomiting has not been studied for pain. previously in children. The incidence of vomiting, retching or both The purpose of this study was to evaluate the antiemetic effect of P6 acupuncture in children undergoing tonsillectomy. Although acupuncture S. M . YENTIS, M.B., B.S., B.SC., F.C.ANAES.; B. BlSSONNETTE, is painless and tolerated well by adults, we felt M.D., F.R.C.P.C. ; Department of Anaesthesia, The Hospital for Sick Children, University of Toronto, 555 University Avenue, that most children would be too scared to accept Toronto, Ontario M5G 1X8, Canada. Accepted for Pubit when awake; consequently the acupuncture was lication: April 29, 1991. Correspondence to B. B. administered after induction of anaesthesia. We have studied the effect of P6 acupuncture on postoperative vomiting in 45 children undergoing tonsillectomy. After induction of anaesthesia and before the start of surgery, 50% of the patients received P6 acupuncture (in the middle of the ventral surface of the wrist) for 5 min. There was no difference in the incidence of vomiting between the acupuncture (39%) and non-acupuncture (36%) groups. We conclude that, when administered after induction of anaesthesia, P6 acupuncture is ineffective in reducing vomiting after tonsillectomy in children.
Downloaded from http://bja.oxfordjournals.org/ at The Chinese University of Hong Kong on February 22, 2015
METHODS AND RESULTS
SUMMARY
BRITISH JOURNAL OF ANAESTHESIA
780
TABLE I. Patient data (mean (SD or range)) and incidence ofeffective only when administered before the emetic stimulus [4]. However, Ho and colleagues vomiting following tonsillectomy (No. (%)) Control (n = 22) 6.7(2-11) 24(7)
5.7 (2-10) 26(7)
96.0(53.7) 19.8(1.5) 8(36%)
75.5(27.1) 19.4(1.4) 9(39%)
was recorded in the postanaesthetic recovery room (PAR) and ward. Staff, patients and parents were unaware of whether or not acupuncture was given. Other data collected included age, sex, duration of anaesthesia, duration of stay in the PAR, postoperative drug requirements, time to drinking fluids and time to discharge from hospital. Statistical significance (P < 0.05) was determined using the unpaired t test for age, duration of anaesthesia, duration of stay in the PAR and time to drinking and discharge from hospital; chisquare analysis was used for sex distribution, postoperative drug requirements and incidence of vomiting. There was no significant difference between the groups for any of the variables recorded. The incidence of vomiting was 39% and 36%, with and without acupuncture, respectively (table I). All but one patient in each group underwent adenoidectomy in addition to tonsillectomy.
found a significant reduction in postoperative vomiting when electroacupuncture was administered in the recovery room [3]. In another study, no antiemetic effect was demonstrated for acupuncture administered during general anaesthesia [6]. It is thus possible that general anaesthesia is the most important factor in reducing any antiemetic effect of acupuncture. This may be caused partly by a greater incidence of incorrect or inadequate needling, as the patients would be anaesthetized and thus unable to describe the sensation of heaviness or dullness ("Chi") that often accompanies correct placement [2,3]. In addition, administration during anaesthesia would eliminate psychological factors, although "dummy" acupuncture has no antiemetic effect, suggesting that psychological factors are not important [2]. The effect of general anaesthesia on that of acupuncture is unclear, although anaesthesia is more likely to depress than to enhance it [3]. In conclusion, P6 acupuncture administered after induction of anaesthesia is ineffective in reducing postoperative vomiting following paediatric tonsillectomy. Further studies are needed to determine the place of acupuncture in paediatric anaesthesia. However, we suspect mat administration to the awake paediatric patient may prove unacceptable, especially to younger children and their parents.
COMMENT
We were unable to demonstrate any antiemetic effect of P6 acupuncture in children undergoing tonsillectomy. There are several possible reasons for this. First, P6 acupuncture might be ineffective in children, although their description as "strong reactors" would suggest otherwise [5]. Second, it may be ineffective for tonsillectomy; vomiting after tonsillectomy is likely to be multifactorial, related to pharyngeal stimulation, psychological factors, swallowing of blood and administration of opioid drugs. Third, a longer period of time might be required between the acupuncture and surgery, as better results have been achieved when acupuncture was performed 1 h before operation than immediately before induction [2]. It has been suggested that P6 acupuncture is
REFERENCES 1. Van der Walt JH, Jacob R, Murrell D, Bentley M. The perioperative effect of oral prcmedication in children. Anaesthesia and Intensive Care 1990; 18: 5-10. 2. Dundee JW, Ghaly RG, BUI KM, Chestnutt WN, Fitzpatrick KTJ, Lynas AGA. Effect of stimulation of the P6 antiemetic point on postoperative nausea and vomiting. British Journal of Anaesthesia 1989; 63: 612-618. 3. Ho RT, Jawan B, Fung ST, Cheung HK, Lee JH. Electro-acupuncture and postoperative cmesis. Anaesthesia 1990; 45: 327-329. 4. Dundee JW, Ghaly RG, Fitzpatrick KTJ, Abram WP, Lynch GA. Acupuncture prophylaxis of cancer chemotherapy-induced sickness. Journal of the Royal Society of Medicine 1988; 82: 268-721. 5. Mann F. Scientific Aspects of Acupuncture, 2nd Edn. London: Hcinemann, 1981. 6. Weightman WM, Zacharias M, Hcrbison P. Traditional Chinese acupuncture as an antiemetic. British Medical Journal 1987; 295: 1379-1380.
Downloaded from http://bja.oxfordjournals.org/ at The Chinese University of Hong Kong on February 22, 2015
Age (yr) Duration of anaesthesia (min) Time to first drink (min) Time to discharge (h) Postoperative vomiting
Acupuncture (n = 23)
P6 ACUPUNCTURE AND POSTOPERATIVE VOMITING AFTER TONSILLECTOMY IN CHILDREN S. M. YENTIS AND B. BISSONNETTE
After approval by the Human Subjects Review Committee, we obtained informed written consent from the parents of 45 children of ASA physical status I or II presenting for elective tonsillectomy. The children were allocated randomly to two groups, the sizes being determined by power analysis assuming a value for a of 0.05, |3 of 0.2, control incidence of vomiting of 80 % and postacupuncture incidence of 40 %. No premedication was given. Anaesthesia was induced with i.v. thiopentone 5 mg kg"1, atropine 0.02 mg kg"1, and suxamethonium 1.5 mgkg"1. Manual inflation of the lungs (taking care not to inflate the stomach) was followed by tracheal intubation and spontaneous ventilation with 66% nitrous oxide and KEY WORDS 1.5-2.0% isoflurane in oxygen. The children in Anaesthesia: paediatric. Anaesthetic techniques: acupuncone group received acupuncture at the P6 point ture. Surgery: tonsillectomy. paediatric Vomiting:incidence on the left side with 5 min manual stimulation, using sterile, disposable 0.2-mm diameter acuVomiting is common after paediatric tonsil- puncture needles. The acupuncture was adlectomy, with a reported incidence of up to 81 % ministered by one investigator (S. Y.) immediately [1]. Stimulation of the P6 acupuncture point has after tracheal intubation and before the start of been shown to reduce nausea and vomiting surgery. significantly in adults undergoing gynaecological I.m. codeine 1.5 mgkg"1 was administered to procedures [2, 3] and chemotherapy [4], and has all patients at the end of surgery. Estimated fluid no side effects [2]. This point ("Neiguan") is deficit and maintenance requirements were resituated two "Chinese inches" (two widths of the placed with i.v. Ringer's lactate solution. After interphalangeal joint of the patient's thumb) operation, i.m. dimenhydrinate 1.0 mgkg"1 was proximal to the distal skin crease of the wrist [2]. available if the incidence of vomiting exceeded Children often respond well to acupuncture in three episodes during any 1-h period. Further general, and arc included in the group termed i.m. codeine 1.0 mgkg"1 or oral paracetamol "strong reactors" [5]. P6 acupuncture and 10 mg kg"1 was available on the ward as required postoperative vomiting has not been studied for pain. previously in children. The incidence of vomiting, retching or both The purpose of this study was to evaluate the antiemetic effect of P6 acupuncture in children undergoing tonsillectomy. Although acupuncture S. M . YENTIS, M.B., B.S., B.SC., F.C.ANAES.; B. BlSSONNETTE, is painless and tolerated well by adults, we felt M.D., F.R.C.P.C. ; Department of Anaesthesia, The Hospital for Sick Children, University of Toronto, 555 University Avenue, that most children would be too scared to accept Toronto, Ontario M5G 1X8, Canada. Accepted for Pubit when awake; consequently the acupuncture was lication: April 29, 1991. Correspondence to B. B. administered after induction of anaesthesia. We have studied the effect of P6 acupuncture on postoperative vomiting in 45 children undergoing tonsillectomy. After induction of anaesthesia and before the start of surgery, 50% of the patients received P6 acupuncture (in the middle of the ventral surface of the wrist) for 5 min. There was no difference in the incidence of vomiting between the acupuncture (39%) and non-acupuncture (36%) groups. We conclude that, when administered after induction of anaesthesia, P6 acupuncture is ineffective in reducing vomiting after tonsillectomy in children.
Downloaded from http://bja.oxfordjournals.org/ at The Chinese University of Hong Kong on February 22, 2015
METHODS AND RESULTS
SUMMARY
BRITISH JOURNAL OF ANAESTHESIA
780
TABLE I. Patient data (mean (SD or range)) and incidence ofeffective only when administered before the emetic stimulus [4]. However, Ho and colleagues vomiting following tonsillectomy (No. (%)) Control (n = 22) 6.7(2-11) 24(7)
5.7 (2-10) 26(7)
96.0(53.7) 19.8(1.5) 8(36%)
75.5(27.1) 19.4(1.4) 9(39%)
was recorded in the postanaesthetic recovery room (PAR) and ward. Staff, patients and parents were unaware of whether or not acupuncture was given. Other data collected included age, sex, duration of anaesthesia, duration of stay in the PAR, postoperative drug requirements, time to drinking fluids and time to discharge from hospital. Statistical significance (P < 0.05) was determined using the unpaired t test for age, duration of anaesthesia, duration of stay in the PAR and time to drinking and discharge from hospital; chisquare analysis was used for sex distribution, postoperative drug requirements and incidence of vomiting. There was no significant difference between the groups for any of the variables recorded. The incidence of vomiting was 39% and 36%, with and without acupuncture, respectively (table I). All but one patient in each group underwent adenoidectomy in addition to tonsillectomy.
found a significant reduction in postoperative vomiting when electroacupuncture was administered in the recovery room [3]. In another study, no antiemetic effect was demonstrated for acupuncture administered during general anaesthesia [6]. It is thus possible that general anaesthesia is the most important factor in reducing any antiemetic effect of acupuncture. This may be caused partly by a greater incidence of incorrect or inadequate needling, as the patients would be anaesthetized and thus unable to describe the sensation of heaviness or dullness ("Chi") that often accompanies correct placement [2,3]. In addition, administration during anaesthesia would eliminate psychological factors, although "dummy" acupuncture has no antiemetic effect, suggesting that psychological factors are not important [2]. The effect of general anaesthesia on that of acupuncture is unclear, although anaesthesia is more likely to depress than to enhance it [3]. In conclusion, P6 acupuncture administered after induction of anaesthesia is ineffective in reducing postoperative vomiting following paediatric tonsillectomy. Further studies are needed to determine the place of acupuncture in paediatric anaesthesia. However, we suspect mat administration to the awake paediatric patient may prove unacceptable, especially to younger children and their parents.
COMMENT
We were unable to demonstrate any antiemetic effect of P6 acupuncture in children undergoing tonsillectomy. There are several possible reasons for this. First, P6 acupuncture might be ineffective in children, although their description as "strong reactors" would suggest otherwise [5]. Second, it may be ineffective for tonsillectomy; vomiting after tonsillectomy is likely to be multifactorial, related to pharyngeal stimulation, psychological factors, swallowing of blood and administration of opioid drugs. Third, a longer period of time might be required between the acupuncture and surgery, as better results have been achieved when acupuncture was performed 1 h before operation than immediately before induction [2]. It has been suggested that P6 acupuncture is
REFERENCES 1. Van der Walt JH, Jacob R, Murrell D, Bentley M. The perioperative effect of oral prcmedication in children. Anaesthesia and Intensive Care 1990; 18: 5-10. 2. Dundee JW, Ghaly RG, BUI KM, Chestnutt WN, Fitzpatrick KTJ, Lynas AGA. Effect of stimulation of the P6 antiemetic point on postoperative nausea and vomiting. British Journal of Anaesthesia 1989; 63: 612-618. 3. Ho RT, Jawan B, Fung ST, Cheung HK, Lee JH. Electro-acupuncture and postoperative cmesis. Anaesthesia 1990; 45: 327-329. 4. Dundee JW, Ghaly RG, Fitzpatrick KTJ, Abram WP, Lynch GA. Acupuncture prophylaxis of cancer chemotherapy-induced sickness. Journal of the Royal Society of Medicine 1988; 82: 268-721. 5. Mann F. Scientific Aspects of Acupuncture, 2nd Edn. London: Hcinemann, 1981. 6. Weightman WM, Zacharias M, Hcrbison P. Traditional Chinese acupuncture as an antiemetic. British Medical Journal 1987; 295: 1379-1380.
Downloaded from http://bja.oxfordjournals.org/ at The Chinese University of Hong Kong on February 22, 2015
Age (yr) Duration of anaesthesia (min) Time to first drink (min) Time to discharge (h) Postoperative vomiting
Acupuncture (n = 23)
