376
A. J. McLINTIC
17. Klughaupt M, Flamm MD, Hancock EW, Harrison
DC. Nonrheumatic mitral insufficiency. Determination of operability and prognosis. Circulation 1969; 309:307-316. 18. Sanders CA, Austen WG, Harthome JW, Dinsmore RE, Scannell JG. Diagnosis and surgical treatment of mitral regurgitation secondary to ruptured chordae tendineae. N Engl J Med 1967; 276:943-949. 19. Roberts WC, Braunwald E, Morrow AG. Acute
ET AL
chordae tendineae. Clinical, hemodynamic and pathological considerations. Circulation 1966' 33:58-70. ' 20. Braunwald E. Mitral regurgitation. Physiological,
clinical and surgical considerations. N Engl J Med 1969; 281 :425-433.
21. Buckley MJ, Mundth ED, Daggett WM, DeSanctis RW, Sanders CA, Austin WG. Surgical therapy for early complications of myocardial infarction. Surgery 1971; 70:814-820.
severe mitral regurgitation secondary to ruptured
Obstetric Anaesthesia in an Achondroplasic Dwarf at a Regional Hospital R. D. A. McARTHUR* Lyell McEwin Health Service, Elizabeth Vale. South Australia Key Words: ANAESTHESIA. OBSTETRIC, COMPLICATIONS: achondroplasia
The well-documented anatomical features of achondroplasia result in a number of anaesthetic problems peculiar to the condition when affected women come to caesarean section. I -6 The shortened skull base, due to premature occipital fusion, may cause limited occipito-atlantic extension; the narrow foramen magnum and possible atlantoaxial instability may render attempts at extension hazardous; the development, as the decades pass, of spinal stenosis exaggerated lumbar lordosis, and possible scoliosis, may cause technical difficulty with epidural access and catheterisation; and the exaggerated cephalopelvic disproportion aggravates the recognised late pregnancy risks of decreased cardiorespiratory reserve, acid aspiration, and aortocaval compression. The question must arise as to what level of clinical sophistication is necessary to provide safe anaesthesia for these patients. This report is of a patient managed successfully at a district general hospital with a delivery rate of around 1700 births per annum. CASE REPORT The patient was a 34-year-old primigravid achondroplastic, 118 cm tall, referred from the *F.CAnaes .. F.F.A.R.A.CS .. Director of Anaesthesia. Address for Reprints: Dr. R. D. A. McArthur. Department of Anaesthesia. Lyell McEwin Health Service. Haydown Road. Elizabeth Vale. South Australia 5112. Australia. Accepted for publication April 30. 1992
antenatal clinic to the medical and anaesthetic outpatient clinics at 13 weeks' gestation. She was subsequently followed by all three clinics concurrently. From 20 weeks she expressed an unwavering preference for general anaesthesia. She had a history of two previous apparently uneventful general anaesthetics, at 15 years for appendicectomy and at 31 years for laparoscopy and diathermy for right tubal adhesions. At the outset of her care she was noted to have hypertension and asthma, both of mild degree, but she maintained good health throughout gestation until requiring admission at 36 weeks for stabilisation of her blood pressure. Pulmonary function tests at 28 weeks were reported as being within normal limits, though with significant improvement after bronchodilator treatment. Subsequently she was maintained on Ventolin Rotacaps p.r.n. and did not develop any unusual respiratory limitations. Her potential intubation difficulty was assessed by simple pharyngoscopy 7 and radiological examination 8 of her skull and cervical spine. This was deemed necessary in case her pregnant state had altered the anatomical condition which had apparently not impeded intubation previously. The results were encouraging, with a Grade 1 pharyngoscopy and satisfactory flexion and extension views. She underwent elective caesarean section at term. The anaesthetic sequence was as follows: Anaesthesia and Intensive Care, l'ol. ]0. So. 3, August, 199]
CASE REPORT
Antacid therapy was administered 30 minutes preoperatively with sodium citrate and cimetidine (Tagamet Express® ) 800 mg dissolved in 30 ml of water. Prolonged preoxygenation was given with the patient in the left lateral position while monitoring sensors were attached and a combined infusion of Hartmann's solution and Haemaccel® commenced. A standard rapid sequence induction followed using thiopentone 200 mg and cricoid pressure. Tracheal intubation was achieved using suxamethonium 75 mg, without any undue neck extension, with a ready acceptance of a 7 mm cuffed tube. Anaesthesia was maintained with N 20/0 2 50%, isoflurane 0.5%, vecuronium 4 mg and manual intermittent positive pressure ventilation. 6 Muscle relaxation was reversed with neostigmine 2.5 mg and atropine 1.2 mg intravenously. The induction-delivery interval was 26 minutes and total anaesthetic time 60 minutes. A child was delivered without any unexpected difficulty, showing some stigmata of achondroplasia. His Apgar scores were 8 and 10 at one and five minutes respectively. Intraoperative monitoring reflected a gratifying stability of maternal cardiac function and haemoglobin-oxygen saturation throughout the procedure. A real problem was non-invasive blood pressure monitoring where, despite following reported advice 3 to have available a variety of cuff sizes, the shortness and thickness of this patient's upper arms led either to failure of the acrylic grip to hold, or to inaccurately high systolic readings. Radial arterial invasive monitoring remedied this situation, with systolic readings of between 220 and 180 mm being replaced by more acceptable readings in the range of 150 to 125 mmHg. Total intraoperative intravenous fluid administration amounted to 800 ml of crystalloid and 125 ml of colloid. Postoperatively analgesia was maintained with an intravenous pethidine infusion. Supplementary oxygen was given at 4 litres/min through a facemask, and later by intranasal catheter. The patient was monitored briefly in the Special Care Unit (a Level 2 facility) before returning to the postnatal ward. When visited on the first postoperative day she expressed satisfaction with her choice of anaesthetic management. DISCUSSION
It has been suggested, 1.1 0 that although the risks
of general anaesthesia are significant in achondroplasia and similar syndromes, the situation militates against the advisability of regional analgesia without a cogent indication. This view is being increasingly questioned 2•5 as the Anaesthesia and Intensive Care, Vol. 20, No. 3, August, 1992
377
passage of time brings increasing experience. One advantage of regional anaesthesia, particularly of epidural block, is stated to be the titratability of drug dosage. However, in view of the equivocal nature of the situation, patients must be dealt with individually, and this mother quickly dashed the hopes of her anaesthetist by her early and unwavering choice of general anaesthesia. If she had chosen to try an epidural block, she would have received 2% lignocaine with adrenaline, which is the standard agent for caesarean sections in this hospital. This has been reported as being safely used on a non-achondroplastic dwarf within the past two years. I I Mather8 in 1966 described an index case of intubation difficulty in a 42-year-old male achondroplastic. Mayhew and colleagues9 dealing with a younger, non-obstetric, group agreed with Walts and colleagues I that smaller than expected tube sizes were usually necessary. In contrast, over subsequent years some reports 2 •6 have indicated that in pregnant achondroplastics intubation problems have not been as great as expected, and this was certainly so in this patient. It may be that pregnant females in their third or fourth decade represent a subgroup who have survived the deformity-related risks of earlier life and have not yet acquired those of the fifth decade and beyond. Despite marked facial stigmata in this patient the predictive value of pharyngoscopy as described by Mallampati et al.was vindicated. As well as her cervical X-ray reports being reassuring, no significant extension of the patient's head was necessary. The general principles of management suggested by Kalla and coworkers 6 were followed with gratifying results. At no stage did the patient become unduly anxious, hopefully because she was aware of the early and well co-ordinated obstetric, medical and anaesthetic team approach. She suffered surprisingly less than expected reduction in cardiorespiratory reserve, possibly because of an 'anterior lie' of her enlarging uterus inclining forward against a lax abdominal wall rather than rising significantly into her thorax. However during the operation manual IPPV was chosen with a view to enabling moment-to-moment adjustments of inspiratory pressure, to balance ventilatory needs with the mechanical problem of delivery. The patient had admitted to no antenatal oesophageal reflux, but the usual precautions against acid aspiration and aortocaval compression were emphasised and appeared to be effective. The difficulties encountered with the blood pressure cuffs, and the rapid success with intraarterial line monitoring suggest that the latter is worthwhile when it is available. A bonus in this
378
R. D. A. McARTHUR
patient was that, despite her relatively large arm circumference, her veins and arteries were readily accessible. In conclusion, whatever the technique, it appears that with close co-operation between obstetrician, physician, and anaesthetist, the problems peculiar to this situation are perhaps more readily dealt with than might be expected. The management of such a patient may be safely undertaken in a regional hospital setting with adequate expertise and support facilities and, in the same circumstances, achondroplastic women need not be denied at least a trial of epidural blockade if they so desire. ACKNOWLEDGEMENTS I would like to acknowledge the clinical co-operation of Drs. Ian Hocking and Judith Searle, obstetricians, Dr. Bill Jeffries, physician, and my anaesthetic colleagues Drs. Foote and Waldow. My thanks are due to Ms. Coral Arnold for typing the manuscript. REFERENCES 1. Waits LF, Fineman G, Wyatt GM. Anaesthesia for dwarfs and other patients of small stature. Can Anaesth Soc J 1975; 22:703-709. 2. Cohen SE. Anaesthesia for cesarian section in achondroplasia. Anesthesiology 1900; 52:264-266.
3. Wangaman WR, Krye JJ, Andrews MJ. Epidural anaesthesia for cesarian section and tuballigation in an achondroplastic dwarf. J Am Assoc Nurse Anesth 1986; 54:436-437. 4. Brimacombe JR, Caunt JA. Anaesthesia in a gravid achondroplastic dwarf. Anaesthesia 1990; 45: 132-134. 5. Wardall GJ, Frame WR. Extradural anaesthesia for caesarian section in achondroplasia. Br J Anaes 1990; 64:367-370. 6. Kalla GN, Fening E, Obiaya MO. Anaesthetic management of achondroplasia. Br J Anaesth 1986; 58: 117-119. 7. Mallampati SR, Gatt SP, Guignold et al. A clinical sign to predict the difficult intubation: a prospective study. Can Anaesth Soc J 1985; 32:429-434. 8. Mather JS. Impossible direct laryngoscopy in achondroplasia. Anaesthesia 1966; 21 :244-248. 9. Mayhew JF, Katz J, Miner M, Leiman BC. Anaesthesia for the achondroplastic dwarf. Can Anaesth 1986; 33:216-221. 10. Katz J, Benumof J, Kadis LB eds. Anaesthesia and Uncommon Diseases. 2nd Ed. W. B. Saunders & Co 1981; 578-580. I!. Rodney GE, Callander CC, Harmer M. Spondyloepiphyseal dysplasia congenita; caesarian section under epidural anaesthesia. Anaesthesia 1991; 46:648-650.
Awareness During Anaesthesia and Post Traumatic Stress Disorder A. D. MACLEOD* AND E. MAYCOCKt Christchurch Hospital. Christchurch, New Zealand Key Words: ANAESTHESIA; COMPLICATION: awareness, post traumatic stress disorder
Awareness during anaesthesia may result in severe psychiatric sequelae such as post traumatic stress disorder. This psychiatric complication is more likely if pain accompanies the awareness. Explanation and simple reassurance are not adequate management. With early psychiatric interventions the prognosis of post traumatic stress disorder may be improved. The introduction of curare to anaesthesia in 1942 allowed general anaesthesia to become lighter and safer. I The first published account of awareness *F.R.A.N.Z.C.P .. Consultant Psychiatrist. tF.F.A.R.A.C.S .• Specialist Anaesthetist. Address for Reprints: Dr. A. D. Macleod, Consultant Psychiatrist, Psychiatric Consultation Service, Christchurch Hospital. Private Bag, Christchurch. New Zealand. Accepted for publication April 14. 1992
during anaesthesia was by Winterbottom in 1950. 2 Wilson 3 defined awareness as 'the ability of the patient to recall, with or without prompting, any event occurring during anaesthesia'. This conscious recollection of events during anaesthesia is significantly less common than those who recall under hypnosis, or dream, conversations or events occurring during their recent anaesthetic experience. Awareness during anaesthesia occurs in 0.5 to 1% of anaesthetic cases,4,5 most frequently in those requiring a 'crash induction', I such as for an emergency caesarian section. 6 About 10% of patients who recall intra-operative events experience associated pain. 7 Unfortunately there is no simple and practical method to measure the depth of anaesthesia I which most probably varies continually throughout the anaesthetic procedure. 8 Anaesthesia and Intensive Care. Vol. 20. No. 3. August. 1992
A. J. McLINTIC
17. Klughaupt M, Flamm MD, Hancock EW, Harrison
DC. Nonrheumatic mitral insufficiency. Determination of operability and prognosis. Circulation 1969; 309:307-316. 18. Sanders CA, Austen WG, Harthome JW, Dinsmore RE, Scannell JG. Diagnosis and surgical treatment of mitral regurgitation secondary to ruptured chordae tendineae. N Engl J Med 1967; 276:943-949. 19. Roberts WC, Braunwald E, Morrow AG. Acute
ET AL
chordae tendineae. Clinical, hemodynamic and pathological considerations. Circulation 1966' 33:58-70. ' 20. Braunwald E. Mitral regurgitation. Physiological,
clinical and surgical considerations. N Engl J Med 1969; 281 :425-433.
21. Buckley MJ, Mundth ED, Daggett WM, DeSanctis RW, Sanders CA, Austin WG. Surgical therapy for early complications of myocardial infarction. Surgery 1971; 70:814-820.
severe mitral regurgitation secondary to ruptured
Obstetric Anaesthesia in an Achondroplasic Dwarf at a Regional Hospital R. D. A. McARTHUR* Lyell McEwin Health Service, Elizabeth Vale. South Australia Key Words: ANAESTHESIA. OBSTETRIC, COMPLICATIONS: achondroplasia
The well-documented anatomical features of achondroplasia result in a number of anaesthetic problems peculiar to the condition when affected women come to caesarean section. I -6 The shortened skull base, due to premature occipital fusion, may cause limited occipito-atlantic extension; the narrow foramen magnum and possible atlantoaxial instability may render attempts at extension hazardous; the development, as the decades pass, of spinal stenosis exaggerated lumbar lordosis, and possible scoliosis, may cause technical difficulty with epidural access and catheterisation; and the exaggerated cephalopelvic disproportion aggravates the recognised late pregnancy risks of decreased cardiorespiratory reserve, acid aspiration, and aortocaval compression. The question must arise as to what level of clinical sophistication is necessary to provide safe anaesthesia for these patients. This report is of a patient managed successfully at a district general hospital with a delivery rate of around 1700 births per annum. CASE REPORT The patient was a 34-year-old primigravid achondroplastic, 118 cm tall, referred from the *F.CAnaes .. F.F.A.R.A.CS .. Director of Anaesthesia. Address for Reprints: Dr. R. D. A. McArthur. Department of Anaesthesia. Lyell McEwin Health Service. Haydown Road. Elizabeth Vale. South Australia 5112. Australia. Accepted for publication April 30. 1992
antenatal clinic to the medical and anaesthetic outpatient clinics at 13 weeks' gestation. She was subsequently followed by all three clinics concurrently. From 20 weeks she expressed an unwavering preference for general anaesthesia. She had a history of two previous apparently uneventful general anaesthetics, at 15 years for appendicectomy and at 31 years for laparoscopy and diathermy for right tubal adhesions. At the outset of her care she was noted to have hypertension and asthma, both of mild degree, but she maintained good health throughout gestation until requiring admission at 36 weeks for stabilisation of her blood pressure. Pulmonary function tests at 28 weeks were reported as being within normal limits, though with significant improvement after bronchodilator treatment. Subsequently she was maintained on Ventolin Rotacaps p.r.n. and did not develop any unusual respiratory limitations. Her potential intubation difficulty was assessed by simple pharyngoscopy 7 and radiological examination 8 of her skull and cervical spine. This was deemed necessary in case her pregnant state had altered the anatomical condition which had apparently not impeded intubation previously. The results were encouraging, with a Grade 1 pharyngoscopy and satisfactory flexion and extension views. She underwent elective caesarean section at term. The anaesthetic sequence was as follows: Anaesthesia and Intensive Care, l'ol. ]0. So. 3, August, 199]
CASE REPORT
Antacid therapy was administered 30 minutes preoperatively with sodium citrate and cimetidine (Tagamet Express® ) 800 mg dissolved in 30 ml of water. Prolonged preoxygenation was given with the patient in the left lateral position while monitoring sensors were attached and a combined infusion of Hartmann's solution and Haemaccel® commenced. A standard rapid sequence induction followed using thiopentone 200 mg and cricoid pressure. Tracheal intubation was achieved using suxamethonium 75 mg, without any undue neck extension, with a ready acceptance of a 7 mm cuffed tube. Anaesthesia was maintained with N 20/0 2 50%, isoflurane 0.5%, vecuronium 4 mg and manual intermittent positive pressure ventilation. 6 Muscle relaxation was reversed with neostigmine 2.5 mg and atropine 1.2 mg intravenously. The induction-delivery interval was 26 minutes and total anaesthetic time 60 minutes. A child was delivered without any unexpected difficulty, showing some stigmata of achondroplasia. His Apgar scores were 8 and 10 at one and five minutes respectively. Intraoperative monitoring reflected a gratifying stability of maternal cardiac function and haemoglobin-oxygen saturation throughout the procedure. A real problem was non-invasive blood pressure monitoring where, despite following reported advice 3 to have available a variety of cuff sizes, the shortness and thickness of this patient's upper arms led either to failure of the acrylic grip to hold, or to inaccurately high systolic readings. Radial arterial invasive monitoring remedied this situation, with systolic readings of between 220 and 180 mm being replaced by more acceptable readings in the range of 150 to 125 mmHg. Total intraoperative intravenous fluid administration amounted to 800 ml of crystalloid and 125 ml of colloid. Postoperatively analgesia was maintained with an intravenous pethidine infusion. Supplementary oxygen was given at 4 litres/min through a facemask, and later by intranasal catheter. The patient was monitored briefly in the Special Care Unit (a Level 2 facility) before returning to the postnatal ward. When visited on the first postoperative day she expressed satisfaction with her choice of anaesthetic management. DISCUSSION
It has been suggested, 1.1 0 that although the risks
of general anaesthesia are significant in achondroplasia and similar syndromes, the situation militates against the advisability of regional analgesia without a cogent indication. This view is being increasingly questioned 2•5 as the Anaesthesia and Intensive Care, Vol. 20, No. 3, August, 1992
377
passage of time brings increasing experience. One advantage of regional anaesthesia, particularly of epidural block, is stated to be the titratability of drug dosage. However, in view of the equivocal nature of the situation, patients must be dealt with individually, and this mother quickly dashed the hopes of her anaesthetist by her early and unwavering choice of general anaesthesia. If she had chosen to try an epidural block, she would have received 2% lignocaine with adrenaline, which is the standard agent for caesarean sections in this hospital. This has been reported as being safely used on a non-achondroplastic dwarf within the past two years. I I Mather8 in 1966 described an index case of intubation difficulty in a 42-year-old male achondroplastic. Mayhew and colleagues9 dealing with a younger, non-obstetric, group agreed with Walts and colleagues I that smaller than expected tube sizes were usually necessary. In contrast, over subsequent years some reports 2 •6 have indicated that in pregnant achondroplastics intubation problems have not been as great as expected, and this was certainly so in this patient. It may be that pregnant females in their third or fourth decade represent a subgroup who have survived the deformity-related risks of earlier life and have not yet acquired those of the fifth decade and beyond. Despite marked facial stigmata in this patient the predictive value of pharyngoscopy as described by Mallampati et al.was vindicated. As well as her cervical X-ray reports being reassuring, no significant extension of the patient's head was necessary. The general principles of management suggested by Kalla and coworkers 6 were followed with gratifying results. At no stage did the patient become unduly anxious, hopefully because she was aware of the early and well co-ordinated obstetric, medical and anaesthetic team approach. She suffered surprisingly less than expected reduction in cardiorespiratory reserve, possibly because of an 'anterior lie' of her enlarging uterus inclining forward against a lax abdominal wall rather than rising significantly into her thorax. However during the operation manual IPPV was chosen with a view to enabling moment-to-moment adjustments of inspiratory pressure, to balance ventilatory needs with the mechanical problem of delivery. The patient had admitted to no antenatal oesophageal reflux, but the usual precautions against acid aspiration and aortocaval compression were emphasised and appeared to be effective. The difficulties encountered with the blood pressure cuffs, and the rapid success with intraarterial line monitoring suggest that the latter is worthwhile when it is available. A bonus in this
378
R. D. A. McARTHUR
patient was that, despite her relatively large arm circumference, her veins and arteries were readily accessible. In conclusion, whatever the technique, it appears that with close co-operation between obstetrician, physician, and anaesthetist, the problems peculiar to this situation are perhaps more readily dealt with than might be expected. The management of such a patient may be safely undertaken in a regional hospital setting with adequate expertise and support facilities and, in the same circumstances, achondroplastic women need not be denied at least a trial of epidural blockade if they so desire. ACKNOWLEDGEMENTS I would like to acknowledge the clinical co-operation of Drs. Ian Hocking and Judith Searle, obstetricians, Dr. Bill Jeffries, physician, and my anaesthetic colleagues Drs. Foote and Waldow. My thanks are due to Ms. Coral Arnold for typing the manuscript. REFERENCES 1. Waits LF, Fineman G, Wyatt GM. Anaesthesia for dwarfs and other patients of small stature. Can Anaesth Soc J 1975; 22:703-709. 2. Cohen SE. Anaesthesia for cesarian section in achondroplasia. Anesthesiology 1900; 52:264-266.
3. Wangaman WR, Krye JJ, Andrews MJ. Epidural anaesthesia for cesarian section and tuballigation in an achondroplastic dwarf. J Am Assoc Nurse Anesth 1986; 54:436-437. 4. Brimacombe JR, Caunt JA. Anaesthesia in a gravid achondroplastic dwarf. Anaesthesia 1990; 45: 132-134. 5. Wardall GJ, Frame WR. Extradural anaesthesia for caesarian section in achondroplasia. Br J Anaes 1990; 64:367-370. 6. Kalla GN, Fening E, Obiaya MO. Anaesthetic management of achondroplasia. Br J Anaesth 1986; 58: 117-119. 7. Mallampati SR, Gatt SP, Guignold et al. A clinical sign to predict the difficult intubation: a prospective study. Can Anaesth Soc J 1985; 32:429-434. 8. Mather JS. Impossible direct laryngoscopy in achondroplasia. Anaesthesia 1966; 21 :244-248. 9. Mayhew JF, Katz J, Miner M, Leiman BC. Anaesthesia for the achondroplastic dwarf. Can Anaesth 1986; 33:216-221. 10. Katz J, Benumof J, Kadis LB eds. Anaesthesia and Uncommon Diseases. 2nd Ed. W. B. Saunders & Co 1981; 578-580. I!. Rodney GE, Callander CC, Harmer M. Spondyloepiphyseal dysplasia congenita; caesarian section under epidural anaesthesia. Anaesthesia 1991; 46:648-650.
Awareness During Anaesthesia and Post Traumatic Stress Disorder A. D. MACLEOD* AND E. MAYCOCKt Christchurch Hospital. Christchurch, New Zealand Key Words: ANAESTHESIA; COMPLICATION: awareness, post traumatic stress disorder
Awareness during anaesthesia may result in severe psychiatric sequelae such as post traumatic stress disorder. This psychiatric complication is more likely if pain accompanies the awareness. Explanation and simple reassurance are not adequate management. With early psychiatric interventions the prognosis of post traumatic stress disorder may be improved. The introduction of curare to anaesthesia in 1942 allowed general anaesthesia to become lighter and safer. I The first published account of awareness *F.R.A.N.Z.C.P .. Consultant Psychiatrist. tF.F.A.R.A.C.S .• Specialist Anaesthetist. Address for Reprints: Dr. A. D. Macleod, Consultant Psychiatrist, Psychiatric Consultation Service, Christchurch Hospital. Private Bag, Christchurch. New Zealand. Accepted for publication April 14. 1992
during anaesthesia was by Winterbottom in 1950. 2 Wilson 3 defined awareness as 'the ability of the patient to recall, with or without prompting, any event occurring during anaesthesia'. This conscious recollection of events during anaesthesia is significantly less common than those who recall under hypnosis, or dream, conversations or events occurring during their recent anaesthetic experience. Awareness during anaesthesia occurs in 0.5 to 1% of anaesthetic cases,4,5 most frequently in those requiring a 'crash induction', I such as for an emergency caesarian section. 6 About 10% of patients who recall intra-operative events experience associated pain. 7 Unfortunately there is no simple and practical method to measure the depth of anaesthesia I which most probably varies continually throughout the anaesthetic procedure. 8 Anaesthesia and Intensive Care. Vol. 20. No. 3. August. 1992
