- Email: [email protected]
iliohypogastric blocks for cesarean delivery in a patient with type II spinal muscular atrophy
International Journal of Obstetric Anesthesia (2016) 25, 79–88
CASE REPORTS
www.obstetanesthesia.com
Transversus abdominis plane and ilioinguinal/ iliohypogastric blocks for cesarean delivery in a patient with type II spinal muscular atrophy J.C. Coffman, K. Fiorini, G. Ristev, W. Beeston, R.H. Small Department of Anesthesiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
ABSTRACT While neuraxial and general anesthetic techniques are most commonly utilized for cesarean delivery, there are rare instances in which alternative techniques may be considered. We report a patient with type II spinal muscular atrophy who had relative contraindications to both neuraxial and general anesthesia, and had experienced significant discomfort during two previous cesarean deliveries performed with local anesthetic infiltration. We describe the successful use of bilateral ultrasound-guided transversus abdominis plane and ilioinguinal/iliohypogastric blocks, in addition to intravenous sedation, for cesarean delivery anesthesia. Ó 2015 Elsevier Ltd. All rights reserved.
Keywords: Transversus abdominis plane; Ilioinguinal/iliohypogastric; Cesarean; Spinal muscular atrophy
Introduction
Case report
In the USA, cesarean delivery is most commonly performed under neuraxial or general anesthesia.1 There are rare circumstances in which alternative techniques, such as local anesthetic infiltration or abdominal wall blocks, may be considered. Patient discomfort during surgery and the potential for toxicity with the large volumes of local anesthetic required make local anesthetic infiltration a less favorable technique.2 Regional abdominal wall blocks, such as transversus abdominis plane (TAP) and ilioinguinal/iliohypogastric (IIIH) blocks, have been studied as means of providing postcesarean delivery analgesia,3–6 but rarely have they been described for cesarean delivery anesthesia.7 Compared to infiltration techniques, regional abdominal wall blocks may provide more reliable blockade and potentially limit the total dose of local anesthetic, although evidence is limited. We describe a case in which bilateral ultrasound-guided TAP and IIIH blocks, in addition to intravenous sedation, were effectively utilized for cesarean delivery anesthesia in a patient with type II spinal muscular atrophy (SMA).
A 26-year-old G3P2 woman weighing 83 kg at 36 weeks of gestation presented for repeat cesarean delivery and bilateral tubal ligation via vertical midline incision. Her medical history was significant for type II SMA and she was confined to a wheelchair secondary to profound proximal muscle weakness. She had significant kyphoscoliosis and had Harrington rods from her thoracic spine to her sacrum. Additionally, she had moderately severe restrictive lung disease with a third trimester forced vital capacity (FVC) of 1.59 L (52% of predicted) and forced expiratory volume in one second (FEV1) of 1.45 L (52% of predicted). These values were essentially unchanged from those before pregnancy. She had undergone two previous cesarean deliveries under local anesthetic infiltration (0.5% lidocaine with 1:200 000 epinephrine, 100 mL and 120 mL), in addition to intravenous sedation and intermittent inhaled nitrous oxide/oxygen. This technique was chosen as there was a concern that neuraxial anesthesia would have been difficult to establish and, if successful, may have resulted in respiratory compromise given her comorbidities. As pain control was poor during those procedures, she desired alternative anesthetic management for this delivery. The patient strongly desired avoiding general anesthesia as her Harrington rod surgery was complicated by a six-week period of postoperative intubation
Accepted August 2015 Correspondence to: John C. Coffman MD, The Ohio State University Wexner Medical Center, Department of Anesthesiology, Room N-411 North Doan Hall, 410 West 10th Avenue, Columbus, Ohio 43210, USA. E-mail address: [email protected]
80 and mechanical ventilation due to muscle weakness and restrictive lung disease. Based on a literature review,7 we planned to perform bilateral ultrasound-guided TAP and IIIH blocks with the goal of achieving anesthesia for a vertical midline incision from the umbilicus to just above the symphysis pubis. She was counseled that successful blocks would anesthetize the anterior abdominal wall but she would still require intravenous sedation and peritoneal infiltration with local anesthetic to help minimize visceral discomfort during surgery. She was further counseled that she could require non-invasive positive pressure ventilation, including continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP), and that tracheal intubation could become necessary if adequate ventilation and oxygenation could not be maintained by non-invasive measures. Airway difficulties were not anticipated as she had a 4 cm thyromental distance, normal oral opening, good cervical range of motion, and was Mallampati class II. After receiving oral sodium citrate 15 mL, she was brought to the operating room and positioned supine with left uterine displacement. Standard monitors were placed and supplemental oxygen at 2 L/min via an end-tidal carbon dioxide (ETCO2) nasal cannula was provided before sedation with intravenous midazolam 2 mg and fentanyl 25 lg. For each TAP block, the 8–13 MHz linear ultrasound probe was positioned along the anterior axillary line half-way between the iliac crest and the lower costal margin. In-plane TAP blocks were completed with 0.5% ropivacaine 13 mL and effective spread of medication was visualized bilaterally. The IIIH nerves were identified in close proximity to branches of the deep circumflex iliac artery as the ultrasound probe was positioned between the anterior superior iliac spine (ASIS) and the umbilicus. In-plane IIIH blocks were completed 3 cm from the ASIS with 0.5% ropivacaine 7 mL on each side. 0.5% ropivacaine was selected in order to achieve a dense sensory blockade of the lower abdominal wall, and the total dose of ropivacaine 200 mg remained less than the recommended 3 mg/kg maximum dose.8 A bilateral T8–L1 abdominal wall sensory blockade to pinprick sensation was confirmed before surgery. If the block had been inadequate, infiltration of the incision area with 0.5% lidocaine with 1:200 000 epinephrine and additional intravenous sedation would have been administered before considering conversion to general anesthesia. Intraoperatively, 4 L/min nasal oxygen was provided and sedation was maintained with propofol (15–25 lg/ kg/min) and ketamine (5 lg/kg/min) infusions, along with intermittent doses of fentanyl 25 lg. During the one-hour surgical procedure, she received a total of propofol 120 mg, ketamine 25 mg and fentanyl 75 lg. Intravenous medications were titrated carefully to minimize risks of over sedation and respiratory depression, and she remained appropriately responsive
International Journal of Obstetric Anesthesia to verbal contact throughout the procedure. Her vital signs remained stable throughout with blood pressure ranging between 113–136/58–86 mmHg, heart rate 102–118 beats/min, oxygen saturation 94–100% and her respiratory rate by ETCO2 monitoring was 20– 28 breaths/min. To minimize visceral discomfort, the obstetricians used 0.5% lidocaine with 1:200 000 epinephrine 10 mL for visceral peritoneum infiltration before uterine incision. Delivery of a healthy female infant was uncomplicated, with Apgar scores of 7 and 9 at 1 and 5 min, respectively. To further minimize visceral discomfort, the uterus was not exteriorized during inspection or repair of the uterine incision. She experienced only brief periods of mild discomfort that correlated with surgical manipulation of visceral organs. Both she and her husband felt that her overall comfort level during and after surgery was much improved compared to the previous deliveries performed under local anesthetic infiltration. Pulse oximetry and telemetry were monitored uneventfully overnight. She regained sensation in the area of her incision 10 h later, and her pain remained well-controlled on scheduled doses of oral ibuprofen 800 mg every six hours with oxycodone 10 mg for breakthrough pain. The remainder of her hospital course was uneventful and she was discharged on postoperative day three without any complications.
Discussion In SMA, a genetic defect leads to reduced levels of survival motor neuron (SMN) protein and ultimately causes degeneration of anterior horn cells.9,10 Type II SMA is typically diagnosed before 18 months of age and patients are wheelchair-bound from an early age due to muscle weakness. Additionally, these patients commonly have severe scoliosis that may require corrective spinal instrumentation and often have significant restrictive lung disease.10 Cesarean delivery is common in patients with type II SMA as they often have insufficient muscle strength or an inadequate pelvis for vaginal delivery. However, successful vaginal delivery11,12 and labor epidural analgesia have been reported,12 as has general anesthesia for cesarean delivery.13–16 Although general anesthesia may have been effectively utilized in our patient, she was adamantly opposed due to her history of prolonged intubation and ventilation following spinal surgery. Spinal anesthesia for cesarean delivery has been effectively utilized in type II SMA,17 although failed attempts at neuraxial block placement have been reported.15,16 No attempt at spinal or epidural blockade had previously been made in our patient given anticipated difficulties with block placement. Additionally, previous studies have documented statistically significant decreases in FVC, FEV1 and peak expiratory flow after placement of a spinal block for cesarean delivery.18,19
International Journal of Obstetric Anesthesia These changes are usually well-tolerated by healthy individuals, but may induce significant respiratory compromise in those with underlying pulmonary disease. Our patient had negative experiences during her previous cesarean deliveries using local anesthetic infiltration and intravenous sedation. A case series by Mei et al. described the combined use of TAP and IIIH blocks in effectively providing cesarean delivery anesthesia,7 and we felt that our patient might benefit from a similar approach. Mei et al. and others observed inconsistent blockade of the lower abdominal wall dermatomes after TAP block alone,7,20 and improvement after performing bilateral IIIH blockade.7 The use of an ultrasoundguided technique with 0.5% ropivacaine in our patient likely produced a more reliable block of the lower abdominal wall and led to improved comfort, relative to her previous deliveries. Mei et al. provided small boluses of propofol (40–60 mg) and ketamine (40–60 mg) for discomfort primarily at the time of delivery, which proved to be effective.7 We felt that careful titration of intravenous infusions would be an appropriate way to provide continual sedation and analgesia in our patient, while minimizing risks of over sedation and respiratory depression. Lastly, it was important to minimize visceral discomfort through gentle surgical manipulation and local anesthetic infiltration of the visceral peritoneum. This case presented a unique challenge given the patient’s comorbidities and relative contraindications to both general and neuraxial anesthesia. The use of TAP and IIIH blocks for cesarean delivery anesthesia was effective in providing reliable sensory blockade. Our experience helps to validate the technique previously described by Mei et al. as a potential alternative to local anesthetic infiltration in these rare cases.
References 1. Bucklin BA, Hawkins JL, Anderson JR, Ullrich FA. Obstetric anesthesia workforce survey: twenty-year update. Anesthesiology 2005;103:645–53. 2. Tsen LC. Anesthesia for Cesarean Delivery: Local Anesthesia. In: Chestnut DH, editor. Obstetric Anesthesia Principles and Practice. 5th ed. Philadelphia: Elsevier Saunders; 2014. p. 577–8. 3. Mishriky BM, George RB, Habib AS. Transversus abdominis plane block for analgesia after Cesarean delivery: a systematic review and meta-analysis. Can J Anaesth 2012;59:766–78. 0959-289X/$ - see front matter Ó 2015 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijoa.2015.08.016
81 4. Bell EA, Jones BP, Olufolabi AJ, et al. Iliohypogastric-ilioinguinal peripheral nerve block for post-Cesarean delivery analgesia decreases morphine use but not opioid-related side effects. Can J Anesth 2002;49:694–700. 5. Wolfson A, Lee AJ, Wong RP, Arheart KL, Penning DH. Bilateral multi-injection iliohypogastric-ilioinguinal nerve block in conjunction with neuraxial morphine is superior to neuraxial morphine alone for postcesarean analgesia. J Clin Anesth 2012;24:298–303. 6. Vallejo MC, Steen TL, Cobb BT, et al. Efficacy of the bilateral ilioinguinal-iliohypogastric block with intrathecal morphine for postoperative cesarean delivery analgesia. ScientificWorldJournal 2012;2012:107316. 7. Mei W, Jin C, Feng L, et al. Bilateral ultrasound-guided transversus abdominis plane block combined with ilioinguinaliliohypogastric nerve block for cesarean delivery anesthesia. Anesth Analg 2011;113:134–7. 8. Williams DJ, Walker JD. A nomogram for calculating the maximum dose of local anaesthetic. Anaesthesia 2014;69:847–53. 9. Lefebvre S, Bu¨rglen L, Reboullet S, et al. Identification and characterization of a spinal muscular atrophy-determining gene. Cell 1995;80:155–65. 10. Arnold WD, Kassar D, Kissel JT. Spinal muscular atrophy: diagnosis and management in a new therapeutic era. Muscle Nerve 2015;51:157–67. 11. Carter GT, Bonekat HW, Milio L. Successful pregnancies in the presence of spinal muscular atrophy: two case reports. Arch Phys Med Rehabil 1994;75:229–31. 12. Weston LA, DiFazio CA. Labor analgesia and anesthesia in a patient with spinal muscular atrophy and vocal cord paralysis. A rare and unusual case report. Reg Anesth 1996;21:350–4. 13. Habib AS, Helsley SE, Millar S, Deballi 3rd P, Muir HA. Anesthesia for cesarean section in a patient with spinal muscular atrophy. J Clin Anesth 2004;16:217–9. 14. Yim R, Kirschner K, Murphy E, Parson J, Winslow C. Successful pregnancy in a patient with spinal muscular atrophy and severe kyphoscoliosis. Am J Phys Med Rehabil 2003;82:222–5. 15. Pugh CP, Healey SK, Crane JM, Young D. Successful pregnancy and spinal muscular atrophy. Obstet Gynecol 2000;95:1034. 16. Bollag L, Kent C, Richebe´ P, Landau R. Anesthetic management of spinal muscle atrophy type II in a parturient. Local Reg Anesth 2011;4:15–20. 17. Maruotti GM, Anfora R, Scanni E, et al. Anesthetic management of a parturient with spinal muscular atrophy type II. J Clin Anesth 2012;24:573–7. 18. Kelly MC, Fitzpatrick KT, Hill DA. Respiratory effects of spinal anaesthesia for caesarean section. Anaesthesia 1996;51:1120–2. 19. Conn DA, Moffat AC, McCallum GD, Thorburn J. Changes in pulmonary function tests during spinal anaesthesia for caesarean section. Int J Obstet Anesth 1993;2:12–4. 20. Lee TH, Barrington MJ, Tran TM, Wong D, Hebbard PD. Comparison of extent of sensory block following posterior and subcostal approaches to ultrasound-guided transversus abdominis plane block. Anaesth Intensive Care 2010;38:452–60.
CASE REPORTS
www.obstetanesthesia.com
Transversus abdominis plane and ilioinguinal/ iliohypogastric blocks for cesarean delivery in a patient with type II spinal muscular atrophy J.C. Coffman, K. Fiorini, G. Ristev, W. Beeston, R.H. Small Department of Anesthesiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
ABSTRACT While neuraxial and general anesthetic techniques are most commonly utilized for cesarean delivery, there are rare instances in which alternative techniques may be considered. We report a patient with type II spinal muscular atrophy who had relative contraindications to both neuraxial and general anesthesia, and had experienced significant discomfort during two previous cesarean deliveries performed with local anesthetic infiltration. We describe the successful use of bilateral ultrasound-guided transversus abdominis plane and ilioinguinal/iliohypogastric blocks, in addition to intravenous sedation, for cesarean delivery anesthesia. Ó 2015 Elsevier Ltd. All rights reserved.
Keywords: Transversus abdominis plane; Ilioinguinal/iliohypogastric; Cesarean; Spinal muscular atrophy
Introduction
Case report
In the USA, cesarean delivery is most commonly performed under neuraxial or general anesthesia.1 There are rare circumstances in which alternative techniques, such as local anesthetic infiltration or abdominal wall blocks, may be considered. Patient discomfort during surgery and the potential for toxicity with the large volumes of local anesthetic required make local anesthetic infiltration a less favorable technique.2 Regional abdominal wall blocks, such as transversus abdominis plane (TAP) and ilioinguinal/iliohypogastric (IIIH) blocks, have been studied as means of providing postcesarean delivery analgesia,3–6 but rarely have they been described for cesarean delivery anesthesia.7 Compared to infiltration techniques, regional abdominal wall blocks may provide more reliable blockade and potentially limit the total dose of local anesthetic, although evidence is limited. We describe a case in which bilateral ultrasound-guided TAP and IIIH blocks, in addition to intravenous sedation, were effectively utilized for cesarean delivery anesthesia in a patient with type II spinal muscular atrophy (SMA).
A 26-year-old G3P2 woman weighing 83 kg at 36 weeks of gestation presented for repeat cesarean delivery and bilateral tubal ligation via vertical midline incision. Her medical history was significant for type II SMA and she was confined to a wheelchair secondary to profound proximal muscle weakness. She had significant kyphoscoliosis and had Harrington rods from her thoracic spine to her sacrum. Additionally, she had moderately severe restrictive lung disease with a third trimester forced vital capacity (FVC) of 1.59 L (52% of predicted) and forced expiratory volume in one second (FEV1) of 1.45 L (52% of predicted). These values were essentially unchanged from those before pregnancy. She had undergone two previous cesarean deliveries under local anesthetic infiltration (0.5% lidocaine with 1:200 000 epinephrine, 100 mL and 120 mL), in addition to intravenous sedation and intermittent inhaled nitrous oxide/oxygen. This technique was chosen as there was a concern that neuraxial anesthesia would have been difficult to establish and, if successful, may have resulted in respiratory compromise given her comorbidities. As pain control was poor during those procedures, she desired alternative anesthetic management for this delivery. The patient strongly desired avoiding general anesthesia as her Harrington rod surgery was complicated by a six-week period of postoperative intubation
Accepted August 2015 Correspondence to: John C. Coffman MD, The Ohio State University Wexner Medical Center, Department of Anesthesiology, Room N-411 North Doan Hall, 410 West 10th Avenue, Columbus, Ohio 43210, USA. E-mail address: [email protected]
80 and mechanical ventilation due to muscle weakness and restrictive lung disease. Based on a literature review,7 we planned to perform bilateral ultrasound-guided TAP and IIIH blocks with the goal of achieving anesthesia for a vertical midline incision from the umbilicus to just above the symphysis pubis. She was counseled that successful blocks would anesthetize the anterior abdominal wall but she would still require intravenous sedation and peritoneal infiltration with local anesthetic to help minimize visceral discomfort during surgery. She was further counseled that she could require non-invasive positive pressure ventilation, including continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP), and that tracheal intubation could become necessary if adequate ventilation and oxygenation could not be maintained by non-invasive measures. Airway difficulties were not anticipated as she had a 4 cm thyromental distance, normal oral opening, good cervical range of motion, and was Mallampati class II. After receiving oral sodium citrate 15 mL, she was brought to the operating room and positioned supine with left uterine displacement. Standard monitors were placed and supplemental oxygen at 2 L/min via an end-tidal carbon dioxide (ETCO2) nasal cannula was provided before sedation with intravenous midazolam 2 mg and fentanyl 25 lg. For each TAP block, the 8–13 MHz linear ultrasound probe was positioned along the anterior axillary line half-way between the iliac crest and the lower costal margin. In-plane TAP blocks were completed with 0.5% ropivacaine 13 mL and effective spread of medication was visualized bilaterally. The IIIH nerves were identified in close proximity to branches of the deep circumflex iliac artery as the ultrasound probe was positioned between the anterior superior iliac spine (ASIS) and the umbilicus. In-plane IIIH blocks were completed 3 cm from the ASIS with 0.5% ropivacaine 7 mL on each side. 0.5% ropivacaine was selected in order to achieve a dense sensory blockade of the lower abdominal wall, and the total dose of ropivacaine 200 mg remained less than the recommended 3 mg/kg maximum dose.8 A bilateral T8–L1 abdominal wall sensory blockade to pinprick sensation was confirmed before surgery. If the block had been inadequate, infiltration of the incision area with 0.5% lidocaine with 1:200 000 epinephrine and additional intravenous sedation would have been administered before considering conversion to general anesthesia. Intraoperatively, 4 L/min nasal oxygen was provided and sedation was maintained with propofol (15–25 lg/ kg/min) and ketamine (5 lg/kg/min) infusions, along with intermittent doses of fentanyl 25 lg. During the one-hour surgical procedure, she received a total of propofol 120 mg, ketamine 25 mg and fentanyl 75 lg. Intravenous medications were titrated carefully to minimize risks of over sedation and respiratory depression, and she remained appropriately responsive
International Journal of Obstetric Anesthesia to verbal contact throughout the procedure. Her vital signs remained stable throughout with blood pressure ranging between 113–136/58–86 mmHg, heart rate 102–118 beats/min, oxygen saturation 94–100% and her respiratory rate by ETCO2 monitoring was 20– 28 breaths/min. To minimize visceral discomfort, the obstetricians used 0.5% lidocaine with 1:200 000 epinephrine 10 mL for visceral peritoneum infiltration before uterine incision. Delivery of a healthy female infant was uncomplicated, with Apgar scores of 7 and 9 at 1 and 5 min, respectively. To further minimize visceral discomfort, the uterus was not exteriorized during inspection or repair of the uterine incision. She experienced only brief periods of mild discomfort that correlated with surgical manipulation of visceral organs. Both she and her husband felt that her overall comfort level during and after surgery was much improved compared to the previous deliveries performed under local anesthetic infiltration. Pulse oximetry and telemetry were monitored uneventfully overnight. She regained sensation in the area of her incision 10 h later, and her pain remained well-controlled on scheduled doses of oral ibuprofen 800 mg every six hours with oxycodone 10 mg for breakthrough pain. The remainder of her hospital course was uneventful and she was discharged on postoperative day three without any complications.
Discussion In SMA, a genetic defect leads to reduced levels of survival motor neuron (SMN) protein and ultimately causes degeneration of anterior horn cells.9,10 Type II SMA is typically diagnosed before 18 months of age and patients are wheelchair-bound from an early age due to muscle weakness. Additionally, these patients commonly have severe scoliosis that may require corrective spinal instrumentation and often have significant restrictive lung disease.10 Cesarean delivery is common in patients with type II SMA as they often have insufficient muscle strength or an inadequate pelvis for vaginal delivery. However, successful vaginal delivery11,12 and labor epidural analgesia have been reported,12 as has general anesthesia for cesarean delivery.13–16 Although general anesthesia may have been effectively utilized in our patient, she was adamantly opposed due to her history of prolonged intubation and ventilation following spinal surgery. Spinal anesthesia for cesarean delivery has been effectively utilized in type II SMA,17 although failed attempts at neuraxial block placement have been reported.15,16 No attempt at spinal or epidural blockade had previously been made in our patient given anticipated difficulties with block placement. Additionally, previous studies have documented statistically significant decreases in FVC, FEV1 and peak expiratory flow after placement of a spinal block for cesarean delivery.18,19
International Journal of Obstetric Anesthesia These changes are usually well-tolerated by healthy individuals, but may induce significant respiratory compromise in those with underlying pulmonary disease. Our patient had negative experiences during her previous cesarean deliveries using local anesthetic infiltration and intravenous sedation. A case series by Mei et al. described the combined use of TAP and IIIH blocks in effectively providing cesarean delivery anesthesia,7 and we felt that our patient might benefit from a similar approach. Mei et al. and others observed inconsistent blockade of the lower abdominal wall dermatomes after TAP block alone,7,20 and improvement after performing bilateral IIIH blockade.7 The use of an ultrasoundguided technique with 0.5% ropivacaine in our patient likely produced a more reliable block of the lower abdominal wall and led to improved comfort, relative to her previous deliveries. Mei et al. provided small boluses of propofol (40–60 mg) and ketamine (40–60 mg) for discomfort primarily at the time of delivery, which proved to be effective.7 We felt that careful titration of intravenous infusions would be an appropriate way to provide continual sedation and analgesia in our patient, while minimizing risks of over sedation and respiratory depression. Lastly, it was important to minimize visceral discomfort through gentle surgical manipulation and local anesthetic infiltration of the visceral peritoneum. This case presented a unique challenge given the patient’s comorbidities and relative contraindications to both general and neuraxial anesthesia. The use of TAP and IIIH blocks for cesarean delivery anesthesia was effective in providing reliable sensory blockade. Our experience helps to validate the technique previously described by Mei et al. as a potential alternative to local anesthetic infiltration in these rare cases.
References 1. Bucklin BA, Hawkins JL, Anderson JR, Ullrich FA. Obstetric anesthesia workforce survey: twenty-year update. Anesthesiology 2005;103:645–53. 2. Tsen LC. Anesthesia for Cesarean Delivery: Local Anesthesia. In: Chestnut DH, editor. Obstetric Anesthesia Principles and Practice. 5th ed. Philadelphia: Elsevier Saunders; 2014. p. 577–8. 3. Mishriky BM, George RB, Habib AS. Transversus abdominis plane block for analgesia after Cesarean delivery: a systematic review and meta-analysis. Can J Anaesth 2012;59:766–78. 0959-289X/$ - see front matter Ó 2015 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijoa.2015.08.016
81 4. Bell EA, Jones BP, Olufolabi AJ, et al. Iliohypogastric-ilioinguinal peripheral nerve block for post-Cesarean delivery analgesia decreases morphine use but not opioid-related side effects. Can J Anesth 2002;49:694–700. 5. Wolfson A, Lee AJ, Wong RP, Arheart KL, Penning DH. Bilateral multi-injection iliohypogastric-ilioinguinal nerve block in conjunction with neuraxial morphine is superior to neuraxial morphine alone for postcesarean analgesia. J Clin Anesth 2012;24:298–303. 6. Vallejo MC, Steen TL, Cobb BT, et al. Efficacy of the bilateral ilioinguinal-iliohypogastric block with intrathecal morphine for postoperative cesarean delivery analgesia. ScientificWorldJournal 2012;2012:107316. 7. Mei W, Jin C, Feng L, et al. Bilateral ultrasound-guided transversus abdominis plane block combined with ilioinguinaliliohypogastric nerve block for cesarean delivery anesthesia. Anesth Analg 2011;113:134–7. 8. Williams DJ, Walker JD. A nomogram for calculating the maximum dose of local anaesthetic. Anaesthesia 2014;69:847–53. 9. Lefebvre S, Bu¨rglen L, Reboullet S, et al. Identification and characterization of a spinal muscular atrophy-determining gene. Cell 1995;80:155–65. 10. Arnold WD, Kassar D, Kissel JT. Spinal muscular atrophy: diagnosis and management in a new therapeutic era. Muscle Nerve 2015;51:157–67. 11. Carter GT, Bonekat HW, Milio L. Successful pregnancies in the presence of spinal muscular atrophy: two case reports. Arch Phys Med Rehabil 1994;75:229–31. 12. Weston LA, DiFazio CA. Labor analgesia and anesthesia in a patient with spinal muscular atrophy and vocal cord paralysis. A rare and unusual case report. Reg Anesth 1996;21:350–4. 13. Habib AS, Helsley SE, Millar S, Deballi 3rd P, Muir HA. Anesthesia for cesarean section in a patient with spinal muscular atrophy. J Clin Anesth 2004;16:217–9. 14. Yim R, Kirschner K, Murphy E, Parson J, Winslow C. Successful pregnancy in a patient with spinal muscular atrophy and severe kyphoscoliosis. Am J Phys Med Rehabil 2003;82:222–5. 15. Pugh CP, Healey SK, Crane JM, Young D. Successful pregnancy and spinal muscular atrophy. Obstet Gynecol 2000;95:1034. 16. Bollag L, Kent C, Richebe´ P, Landau R. Anesthetic management of spinal muscle atrophy type II in a parturient. Local Reg Anesth 2011;4:15–20. 17. Maruotti GM, Anfora R, Scanni E, et al. Anesthetic management of a parturient with spinal muscular atrophy type II. J Clin Anesth 2012;24:573–7. 18. Kelly MC, Fitzpatrick KT, Hill DA. Respiratory effects of spinal anaesthesia for caesarean section. Anaesthesia 1996;51:1120–2. 19. Conn DA, Moffat AC, McCallum GD, Thorburn J. Changes in pulmonary function tests during spinal anaesthesia for caesarean section. Int J Obstet Anesth 1993;2:12–4. 20. Lee TH, Barrington MJ, Tran TM, Wong D, Hebbard PD. Comparison of extent of sensory block following posterior and subcostal approaches to ultrasound-guided transversus abdominis plane block. Anaesth Intensive Care 2010;38:452–60.