SPINE Volume 39, Number 3, pp E211-E218 ©2014, Lippincott Williams & Wilkins

SURGERY

Scoliosis Surgery in Children With Congenital Heart Disease Muayad Kadhim, MD,* Ellen Spurrier, MD,† Deepika Thacker, MD,‡ Christian Pizarro, MD,§ and William G. Mackenzie, MD*

Study Design. Retrospective cohort study. Objective. To describe preoperative evaluation, anesthetic and perioperative management, and complications in patients with congenital heart disease (CHD) who underwent surgery to correct a spine deformity. Summary of Background Data. Patients with surgically palliated or repaired CHD may have nearly normal circulation or may have important residual abnormalities that affect the planning and conduct of surgery to correct a spine deformity. Methods. We examined the records of 21 patients with spine deformity who had previous surgical intervention for CHD. Three types of spine surgery and instrumentation were examined, posterior spinal fusion with instrumentation (PSFI), growing rod (GR) instrumentation, and vertical expandable prosthetic titanium rib instrumentation (VEPTR). To objectify the degree of preoperative cardiac physiological derangement, patients were classified into 3 groups: single ventricle physiology and Fontan circulation (S), two ventricles with no residual abnormal cardiac physiology condition (2N), and two ventricles with residual cardiac physiology problem (2R). Results. Subjects were 8 boys and 13 girls with mean age of 11.1 ± 5.2 years. Sixteen patients underwent surgery to correct scoliosis, 1 to correct kyphosis, and 4 did not undergo surgery. Total number of surgical procedures was 23 (16 PSFI, 5 GR, and 2 VEPTR). On the basis of cardiac physiology, 2 patients belonged

From the Departments of *Orthopaedic Surgery, †Anesthesiology; ‡Cardiology, and §Cardiac Surgery, Alfred I. duPont Hospital for Children, Wilmington, DE. Acknowledgment date: February 8, 2013. Revision date: September 11, 2013. Acceptance date: October 14, 2013. Pedicle screws are FDA approved for adolescent idiopathic scoliosis in adults and adolescents. Growing rods are commonly used for the indication of correcting spine deformity in early onset scoliosis specifically for thoracic curves to improve the respiratory function. The patients evaluated in this manuscript had syndromic spinal deformity. Pedicle screws and growing rods are not FDA approved for this particular indication. No funds were received in support of this work. Relevant financial activities outside the submitted work: board membership, travel/accommodations/meeting expenses. Address correspondence and reprint requests to William G. Mackenzie, MD, Nemours/Alfred I. duPont Hospital for Children, 1600 Rockland Rd, Wilmington, DE; E-mail: [email protected] DOI: 10.1097/BRS.0000000000000083 Spine

2N, 11 were 2R, and 8 were group S. Mean estimated blood loss was 1685 mL during PSFI, 515 mL during GR, and 150 mL during VEPTR. Mean volume of blood transfusion was 44 mL/kg for PSFI, 19 mL/kg for GR, whereas no transfusion was administered during VEPTR. Median intensive care unit stay was 2 days ranging from hours to 78 days. Median hospital length of stay was 7 days ranging from 3 to 93 days. There were no deaths. Conclusion. Given meticulous multidisciplinary planning and execution, major spine surgery can be safely and successfully performed in patients with significant residua of CHD. Key words: congenital heart disease, Fontan circulation, scoliosis surgery, single ventricle, cardiac physiology. Level of Evidence: 4 Spine 2014;39:E211–E218

A

dvancements in the treatment of patients with congenital heart disease (CHD) and improved survival rates have created a challenge of managing other medical conditions such as scoliosis and kyphosis. Many children who are born with CHD undergo thoracic surgery as infants and are at increased risk for the development of scoliosis.1–4 At the time of scoliosis diagnosis, patients with CHD may exhibit a spectrum of residual cardiac issues ranging from minor anatomic abnormalities to major and permanent derangements of cardiac anatomy and/or physiology. Patients with single ventricle physiology undergo multiple staged palliative surgical procedures in the first few years of life culminating in the Fontan procedure. Patients with Fontan circulation will never have normal cardiac physiology as the single cardiac ventricle (left or right) must perform as the systemic pump to the body, whereas blood flows to the lungs passively through a surgical connection of the superior and inferior venae cavae to the pulmonary arteries. There are few published series that describe the surgical treatment of scoliosis in patients with CHD.5–11 Special considerations regarding abnormal circulatory physiology are required during preoperative evaluation, planning for surgery and treatment for such patients. The aim of this study was to describe the management strategy and short-term outcome for patients with CHD who underwent spine surgery at a single institution. www.spinejournal.com

E211

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E211

27/12/13 3:10 PM

SURGERY MATERIALS AND METHODS Medical Record Review After approval from the institutional review board, we conducted a retrospective medical records review of patients with spine deformity who also had a diagnosis of CHD. We identified 21 patients who received care at our institution from 1999 to 2011, including 17 patients who underwent surgery for scoliosis or kyphosis and 4 who did not.

Patient Classification Patients underwent spine surgery using 3 types of instrumentation: vertical expandable prosthetic titanium rib (VEPTR), growing rod (GR), posterior spinal fusion (PSF), and posterior spinal fusion with instrumentation (PSFI). Some patients in the study had more than 1 type of major spine surgery. Minor interventions such as rod lengthening were not included. Spine radiographs were reviewed and deformity pattern was classified into kyphosis, congenital scoliosis, neuromuscular scoliosis, and syndromic scoliosis. Spinal curves were classified as thoracic and thoracolumbar curves when the apex of the major curve was between (T4–T11) and (T12–L4), respectively. A pediatric cardiologist (D.T.) reviewed the preoperative echocardiogram reports and categorized the patients into three groups depending on the cardiac anatomic and physiological status. Patients with a functional single cardiac ventricle or whose cardiac anatomy had necessitated a single ventricle palliative surgery were defined as the single ventricle group (group S). Patients with two functioning ventricles were further classified on the basis of cardiac systolic and diastolic function and presence of a hemodynamically important anatomical lesion. Two groups were identified: two ventricles with no significant functional or anatomic cardiac abnormality (group 2N), and two ventricles with significant residual cardiac abnormalities (group 2R). Cyanosis was defined as oxygen saturation less than 94% at rest in room air. When oxygen saturation was not documented, cyanosis was predicted on the basis of the underlying cardiac physiology at the last preoperative clinic visit (significant right to left shunting or mixing). The patients’ preoperative anesthetic risk was assigned by an anesthesiologist according to the American Society of Anesthesiologists (ASA) standards.12

RESULTS Patient Characteristics Twenty-one patients with CHD and spine deformity were identified; all had previously undergone 1 or more cardiac surgical procedures. There were 8 males and 13 females. Mean age at the evaluation for spine surgery was 11.1 ± 5.2 years. Eleven patients had syndromic scoliosis, 5 patients had neuromuscular scoliosis, 4 patients had congenital scoliosis, and 1 patient had congenital kyphosis. The cardiac diagnosis, cardiac surgery, and associated medical conditions are listed in Table 1. On the basis of the preoperative echocardiogram, 8 patients were in group S, 2 patients were in group 2N, E212

www.spinejournal.com

Spine Surgery in Children With CHD • Kadhim et al

and 11 patients were in group 2R. Three of the 21 patients met criterion for cyanosis at the time of spine surgery. Four patients, 2 in group S and 2 in group 2R were classified as ASA IV and assessed as having an unacceptable risk of severe morbidity or mortality did not undergo surgery. Patient 13 was classified ASA III for GR surgery and later as ASA IV for PSFI. Prothrombin time was marginally increased in 3 patients.

Surgical Management Seventeen patients underwent a total of 23 procedures (16 PSF/PSFI, 5 GR, and 2 VEPTR). Five patients had multiple spine surgical procedures. Patient 4 had a congenital scoliosis, received PSF and anterior fusion with allograft rib strut at age 2.1 years, and at age 4.9 years underwent anterior release with epiphysiodesis and posterior fusion and instrumentation with 1 rod and 2 hooks. This patient developed rod prominence and drainage from the wound and the instrumentation was removed within 4 months. Because of severe progression he was subsequently treated with a rod and 2 hooks with distraction, and the patient had satisfactory outcome. Patients 5 and 13 were treated with GR at ages 6.2 and 8.4 years, respectively, and then underwent PSFI at ages 11.1 and 12.3 years, respectively. Patients 6 and 15 were treated initially with VEPTR and GR, respectively, and later needed revision due to growth (Table 2).

Intraoperative Management All patients were anesthetized by a pediatric anesthesiologist or pediatric cardiac anesthesiologist according to the physiological status based on the presence of significant hemodynamic lesions or a single ventricle. All patients received total intravenous anesthesia, large bore venous access, and intraarterial blood pressure monitoring. Central venous pressure was not routinely monitored because of limited utility in the prone position wherein the value correlates poorly with baseline supine measurements and echocardiographic assessment of intracardiac volume.13 Of note, when a central vein is cannulated to provide secure large bore venous access, potential abnormalities of systemic venous drainage are taken into account in choosing the site. Intraoperative transesophageal echocardiography was not used. Anesthesia and surgery times were longer in PSFI relative to GR and VEPTR surgical procedures. As anticipated, mean estimated blood loss (EBL) and EBL as a percent of estimated blood volume (EBL%) were higher in PSFI group than in the GR and VEPTR groups (Table 3). Five patients whose EBL exceeded 1 blood volume, included 1 patient from group 2N, 2 patients from group 2R, and 2 patients from group S. Although our small numbers preclude statistical analysis, there was no apparent trend toward increased blood loss in patients with residual cardiac abnormalities including the single ventricle group. Fresh or reconstituted whole blood, packed red blood cells, fresh frozen plasma, and/or platelets were used to maintain intravascular volume, oxygen carrying capacity, and adequate blood coagulation. Cell saver was used for blood salvage and reinfusion. To maintain appropriate oxygen carrying capacity, February 2014

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E212

27/12/13 3:10 PM

SURGERY

Spine Surgery in Children With CHD • Kadhim et al

TABLE 1. Patients With Congenital Heart Disease and Spine Deformity Sex

Age

Cardiac Status

Cardiac Diagnosis

OMC

Spine Deformity

Major Curve

Cobb

First Surgery

1

F

13.8

2N

Coarctation of aorta, repair

RAD

Syn scoliosis

…*

…*

PSFI

2

M

10.9

2N

TOF, repair

RAD, CP

NM scoliosis

T

102

PSFI

3

F

11.4

2R mild

TOF, repair



Con scoliosis

TL

37

PSFI

4

M

2.1

2R mild

CCAVC, repair



Con scoliosis

T

58

PSF

5

F

6.2

2R mild

ASD, hypertrophic cardiomyopathy

Sz, RAD, Hn

NM scoliosis

T

55

GR

6

M

2.5

2R mild

Multiple muscular VSDs, coarctation, repair

Charge syn, RAD, Hc, Nc, HpoT

NM scoliosis

T

91

VEPTR

7

M

15.6

2R mod

TOF, PA, repair

DiGeorge syn, RAD

Syn scoliosis

TL

81

PSFI

8

M

15.3

2R mild

DORV, repair



Syn scoliosis

TL

59

PSFI

9

F

17.3

2R mod

Pulmonary stenosis, s/p balloon valvuloplasty, hypertrophic cardiomyopathy

Syn scoliosis

T

69

PSFI

10

M

16.7

2R mod

Subaortic stenosis, repair, dilated cardiomyopathy

Syn scoliosis

T

58

PSFI

11

F

12.5

2R mild

Truncus arteriosus, repair

Con kyphosis

TL

115

PSFI

12

F

15.5

S

Hypoplastic left heart, Fontan

Br, Hm

NM scoliosis

T

46

PSFI

13

F

8.4

S

DORV, hypoplastic left ventricle, Fontan



Syn scoliosis

T

75

GR

14

M

2.7

S

Dextrocardia, DORV, Fontan



Con scoliosis

TL

74

PSFI

15

M

3.5

S

CCAVC, unbalanced to right ventricle, DORV, Fontan

Oa

Syn scoliosis

T

97

GR

16

F

13.3

S

DORV, hypoplastic left ventricle, Fontan

Hm

Syn scoliosis

T

61

PSFI

17

F

13.4

S

HLHS, Fontan

RAD

Syn scoliosis

T

72

PSFI

CP, Sz

NM scoliosis

TL

93

n/a



Con scoliosis

T

68

n/a

Noonan syn, RL, OAD … Fibular hemimelia

Patients precluded from spine surgery 2R mild

Bicuspid aortic valve, ASD repair, Pierre Robin malformation

18

F

6.5

19

F

14.1

20

F

16.0

S

Ebstein anomaly



Syn scoliosis

T

81

n/a

21

F

16.3

S

HLHS



Syn scoliosis

T

57

n/a

2R severe DORV, Goldenhar syn

Patient 18 died before surgery, patient 19 had systemic right ventricle pressure, patient 20 had multiple arrhythmias and severe right ventricle volume overload, and patient 21 had neoaortic valve regurgitation and protein losing enteropathy. *No radiographs were available for this patient. M indicates male; F, female; N, normal; BMI, body mass index; UW, underweight; OW, overweight; TOF, tetralogy of Fallot; CCAVC, complete common atrioventricular canal; ASD, atrial septal defect; VSD, ventricle septal defect; PA, pulmonary atresia; DORV, double outlet right ventricle; HLHS, hypoplastic left heart syndrome; OMC, other medical conditions; RAD, reactive airway disease; Br, bronchiectasis; Hm, hepatomegaly; Hn, hydronephrosis; CP, cerebral palsy; Sz, seizures; Hc, hydrocephalus; Oa, obstructive apnea; RL, restrictive lung disease; OAD, obstructive airway disease; Nc, nephrocalcinosis; HpoT, hypotonia; Syn, syndromic; Con, congenital; NM, neuromuscular; T, thoracic curve; TL, thoracolumbar curve; GR, growing rod; VEPTR, vertical expandable prosthetic titanium rib; PSFI, posterior spinal fusion with instrumentation; PSF, posterior spinal fusion without instrumentation.

hemodilution was avoided by minimizing the amount of crystalloid infused in patients with single ventricle or significant residual cardiac defects (Table 4). Patient 9, who had moderate residual cardiac issues, experienced significant bleeding (EBL = 3500 mL) and was treated with recombinant factor VII in addition to blood product replacement. Spine

Somatosensory evoked potentials and transcranial motor evoked potentials (TcMEP) were used to monitor the sensory and motor pathways to detect and prevent spinal cord injuries during spine surgery. Anesthetic technique was tailored to avoid agents that are known to affect cortical evoked potential interpretation, including nitrous oxide and volatile www.spinejournal.com

E213

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E213

27/12/13 3:10 PM

E214

SPINE130198.indd E214

www.spinejournal.com

15.6

15.3

17.3

16.7

12.5

15.5

8.4

12.3

7

8

9

10

11

12

13

13

S

S

S

S

S

S

S

S

2R mild

2R mod

2R mod

2R mild

2R mod

2R mild

2R mild

2R mild

2R mild

2R mild

2R mild

2R mild

2R mild

2N

2N

No

No

Yes

Yes

Yes

No

No

No

No

No

No

No

No

No

No

No

No

No

No

No

No

No

No

3

3

3

3

3

4

3

3

3

4

3

2

3

3

3

3

3

3

3

2

2

3

2

PSFI (T3–L1) + PO

PSFI (T5–L2)

GR (T2–L4 to L3–L4)

GR (T2–T4 to L3–L4)

PSFI (T11–L4) + Vec

PSFI (T3–L3)

GR (T4–T5 to L1–L2)

PA/PCA

PA/PCA

PA/PCA

PA/PCA

PCA

PA/PCA

PCA

PA

PA/PCA

PSFI (T4–L3) + PO + Vec + AF PSFI (T3–L4)

PCA

PA/PCA

PA

PA

PA

PA

PCA

PCA

PA

PSFI (T3–L4) + PO

PSFI (T4–L3) + PO

PSFI (T3–L3)

PSFI (T3–L5)

VEPTR (third rib to pelvis)

VEPTR (third rib to pelvis)

PSFI (T2–L4) + PO

GR (T4–T5 to L3–L4)

GR (T1–T2 to T12–L1)

PA

PA

PSF (T4–T9) + AF PSF (T4–T10) + ARE

PA

PA

PA

Anesth

PSFI (T12–L3)

PSFI (T1–pelvis)

PSFI (T2–L3)

Surgery

409

513

416

400

489

434

325

271

483

421

628

414

635

292

365

598

448

179

265

151

218

564

596

AT

360

407

317

284

418

331

245

167

449

342

429

307

468

220

249

531

334

112

185

106

141

480

481

OT

850

1532

250

500

950

3500

550

1280

1350

805

3500

1280

2731

250

50

4500

1200

75

150

60

250

926

3300

EBL

21

58

18

59

134

135

39

50

37

23

129

38

67

26

7

237

96

9.5

21

11

13

85

137

EBL%

During Operation

781

1592

196

690

1000

4426

459

1500

1827

1811

3024

753

2081

0

0

3836

397

0

150

0

0

1110

2790

Blood*

CICU

PACU

PICU

PICU

PICU

CICU

PICU

PICU

PICU

PACU

PICU

PACU

2900

2925

1600

1790

1600

3800

1600

1200

2400

2150

CICU

CICU

CICU

CICU

CICU

CICU

CICU

PACU

CICU

CICU

1

3

2

6

6

1

4

1

1

1

12

4 hr

1

78

10

3

1

4 hr

4

3

1

11

4 hr







2

5‡

4 hr









9‡



1

66‡











1



4‡



7

7

3

10

9

7

4

8

16

6

14

5

6

93

20

6

7

4

5

8

5

12

6

Care ICUHUnit LOS† LOMV† LOS†

14000 PACU

5250

5000

1100

900

1400

3750

1200

500

230

1850

5000

7450

Fluid

Postoperative

Patients 4, 5, 6, 13, and 15 had more than 1 spine surgery; each surgery is presented in a separate row in this table. *Blood components used during surgery. †Duration is calculated in days. ‡Mechanical ventilation due to respiratory failure. In the column “Cardiac Status,” 2N denotes two ventricles with no significant residual; 2R, two ventricles with significant residual; S, single ventricle. ASA indicates American Society of Anesthesiologists classification; PSFI, posterior spinal fusion with instrumentation; PSF, posterior spinal fusion without instrumentation; GR, growing rod; VEPTR, vertical expandable prosthetic titanium rib; Anesth, type of anesthesia team; PA, pediatric anesthesiologist; PCA, pediatric cardiac anesthesiologist; AT, anesthesia time; OT, operation time; EBL, estimated blood loss; EBL/BV%, percentage of EBL to the estimated blood volume; PACU, post anesthesia care unit; PICU, pediatric intensive care unit; CICU, cardiac intensive care unit; ICU-LOS, length of intensive care unit stay; LOMV, length of mechanical ventilation; H-LOS, length of hospital stay; AF, anterior fusion; ARE, anterior release and epiphysiodesis; Vec, vertebrectomy; PO, posterior osteotomy.

13.4

4.0

6

17

2.5

6

13.3

11.1

5

16

6.2

5

6.8

6.7

4

15

4.9

4

2.7

2.1

4

3.5

11.4

3

14

10.9

2

15

13.8

1

Age at Cardiac Patient Surgery Status Cyanosis ASA

Preoperative

TABLE 2. Spine Surgical Procedures in Patients With Congenital Heart Disease

SURGERY Spine Surgery in Children With CHD • Kadhim et al

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.

February 2014

27/12/13 3:10 PM

SURGERY

Spine Surgery in Children With CHD • Kadhim et al

TABLE 3. Spine Surgery Related Variables Stratified by Type of Surgery PSFI (n = 13)

Growing Rod (n = 4)

VEPTR (n = 2)

Age (yr)

11.8 ± 4.7

6.3 ± 1.8

3.2 ± 1.1

EBL (mL)

1685 ± 1374

515 ± 428.5

150 ± 141.4

74.8 ± 63

44 ± 34.6

16 ± 13.5

Blood transfusion (mL/kg)

44.2 ± 36.4

19 ± 18.4

0±0

Fluids (mL/kg)

96.7 ± 87.5

106.5 ± 47.2

69.4 ± 2

Anesthesia time (hr)

7.3 ± 2.5

5.9 ± 1.8

5.5 ± 0.9

Surgery time (hr)

5.8 ± 2.2

4.3 ± 1.5

3.9 ± 0.3

3 ± 3.6

2.6 ± 2.4

44 ± 48.1

LOMV (d)

1.3 ± 2.6

0.4 ± 0.9

33 ± 46.7

H-LOS (d)

7.9 ± 3.3

5.6 ± 2.9

56.5 ± 51.6

EBL to blood volume%

ICU-LOS (d)

Study variables were calculated using mean and standard deviation. PSFI indicates posterior spinal fusion with instrumentation; VEPTR, vertical expandable prosthetic titanium rib; EBL, estimated blood loss; ICU-LOS, length of stay in the intensive care unit; LOMV, length of mechanical ventilation; H-LOS, length of stay in hospital.

anesthetics.11 Two patients had significant intraoperative changes in TcMEP. Patient 2 (group 2N) was quadriplegic with a neuromuscular curve and underwent surgical treatment with a unit rod and sublaminar wires. During the final reduction of the curve, the patient had complete loss of all TcMEP signals in the lower extremities, whereas somatosensory evoked potentials were intact. The mean blood pressure was raised to greater than 90 mmHg, in situ bending of the rod was done, and solu-Medrol steroid protocol was instituted as well. TcMEP signals returned only on the right side. Later in the intensive care unit (ICU), the patient began moving his upper and lower extremities spontaneously. This

patient (no. 2) developed a deep wound infection that required drainage and debridement. Patient 17 had changes in TcMEP on the left side, and returned to normal after removal of the T9 screw that has breached the pedicle medially.

Postoperative Course Because of the unique physiology, patients with single ventricle physiology were generally managed postoperatively in the pediatric cardiac intensive care unit (CICU). Remaining patients received care in the general pediatric ICU or the CICU at the discretion of the anesthesiologist. Eight patients developed pleural effusion (1 patient in group 2N, 4 patients

TABLE 4. Study Variables in Patients Who Received Posterior Spinal Fusion Stratified by Type

of Cardiac Physiology

2 V/No Residual (n = 2)

2 V/With Residual (n = 6)

Single V (n = 5)

Age (yr)

12.3 ± 2.0

11.8 ± 5.6

11.4 ± 5.0

EBL (mL)

2113 ± 1678.7

1625 ± 1596

1622.4 ± 1472.8

EBL to blood volume %

111 ± 36.3

64 ± 74.3

79 ± 51.8

Blood transfusion (mL/kg)

65.4 ± 5.7

36.3 ± 39

54 ± 37.8

Fluids (mL/kg)

231 ± 64.3

80.4 ± 88.2

72.3 ± 42

9.7 ± 0.4

7.1 ± 3.0

7 ± 1.6

8±0

5.5 ± 2.6

5.6 ± 1.7

5.6 ± 7.6

2.9 ± 3.6

2.4 ± 2.2

LOMV (d)

2 ± 2.8

1.2 ± 2.9

1.1 ± 2.2

H-LOS (d)

9 ± 4.2

7.9 ± 4.2

7 ± 0.9

Anesthesia time (hr) Surgery time (hr) ICU-LOS (d)

Study variables were calculated using mean and standard deviation. V indicates ventricle(s); EBL, estimated blood loss; ICU-LOS, length of stay in the intensive care unit; LOMV, length of mechanical ventilation; H-LOS, length of stay in hospital.

Spine

www.spinejournal.com

E215

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E215

27/12/13 3:10 PM

SURGERY in group 2R, and 3 patients in group S); 8 developed atelectasis of varying severity. Length of stay in an ICU was in the range from 4 hours to 78 days, median 2 days, and mean 6.5 days. Postoperative mechanical ventilation was not required after 15 operations. Six patients received mechanical ventilation for greater than 24 hours after the surgery; 4 of them required prolonged ventilation due to respiratory failure. Hospital length of stay was in the range from 3 to 93 days with a median of 7 days (Table 2). Patient 6 had severe developmental delay and was thought to have mild cardiac residua (group 2R) and required revision of the VEPTR due to short instrumentation. After an uneventful surgery, the patient developed respiratory failure after 8 days and required prolonged mechanical ventilation. The patient was subsequently diagnosed with significant mitral valve insufficiency and was treated with mitral valve annuloplasty and eventually was discharged from the hospital after 93 days.

Patients Precluded From Surgery Four patients met the orthopedic criteria for spine surgery but did not undergo surgery (Table 1). Patient 18 did not have cardiac contraindications to scoliosis surgery but had multiple congenital anomalies and was dependent on ventilator. The patient had acute cardiorespiratory decompensation at home and died prior to scheduled scoliosis surgery. The other 3 patients were deemed extremely high risk due to cardiovascular status. Patient 19 was diagnosed with markedly elevated right ventricular pressure and later developed nonsustained polymorphic ventricular tachycardia requiring implantation of a cardioverter defibrillator. Patient 20 had a history of multiple arrhythmias of different etiologies that could not be well controlled in spite of medical and interventional management. Patient 21 underwent replacement of her aortic valve and postoperatively developed severe edema, protein losing enteropathy, and persistent melena of uncertain etiology.

DISCUSSION Scoliosis may have a negative impact on cardiorespiratory physiology if left untreated in patients with CHD.5 Impairment of respiratory function due to restrictive pulmonary disease has been reported in otherwise normal children with progressive early onset scoliosis14 and significant adolescent scoliosis.15,16 Patients with idiopathic scoliosis may also develop increased pulmonary vascular resistance and pulmonary artery pressure leading to cor pulmonale.17 Theoretically, these pulmonary pathophysiological changes will have an exaggerated negative impact on patients with a single ventricle or functional abnormalities of the right ventricle and/ or pulmonary valve. Therefore a careful and thorough evaluation of the risk associated with intervention on the spine is essential for patients with CHD. This retrospective review focuses on patient selection, perioperative management, and short-term outcome after 3 types of surgery to correct scoliosis in patients with CHD. In our practice, patients with spine deformity who have CHD are referred to their pediatric cardiologist for evaluation of cardiac fitness prior to scheduling for surgery. The E216

www.spinejournal.com

Spine Surgery in Children With CHD • Kadhim et al

assessment includes history and physical examination, echocardiogram, review of prior diagnostic testing and in some instances further evaluation with cardiac catheterization is required for assessment of intracardiac pressure, pulmonary vascular resistance, accurate cardiac output, and ratio of pulmonary to systemic blood flow. The cardiology assessment is reviewed by a multidisciplinary group including surgeon, pediatric anesthesiologist experienced in providing anesthesia for spine surgery, and a pediatric cardiac anesthesiologist to assess the risks and plan intraoperative management. Patients with moderate to severe residual cardiac abnormalities and patients with single ventricle physiology are managed directly by a pediatric cardiac anesthesiologist either as the primary provider or in collaboration with a pediatric anesthesiologist who routinely provides anesthesia for spine surgery. Intraoperative bleeding is an important risk factor for all pediatric patients undergoing spine surgery. Blood loss during spine surgery is promoted by prone position and multilevel bone decortications.18 Single ventricle patients and patients with important right heart abnormalities are predisposed to increased bleeding secondary to elevated venous pressures with typical central venous pressure ranging from 11 to 15 mm Hg compared with 4 to 6 mm Hg in normal individuals.19 In addition, patients with Fontan circulation commonly exhibit an abnormal coagulation profile, and may have a baseline coagulopathy attributable to impaired hepatic synthetic function.20–22 Techniques reported to decrease blood loss during spine surgery such as controlled hypotension and/or isovolemic hemodilution 23,24 are not used in our management of patients with CHD. Many CHD patients are dependent on normal or elevated hemoglobin concentrations to maximize oxygen carrying capacity, thus hemodilution may not be well tolerated. Large volumes of crystalloid fluid administered during hemodilution will lower plasma oncotic pressure and exacerbate capillary leak in patients who because of their cardiac condition are already prone to pulmonary edema or pleural effusions.6,8 In addition, hemodilution may promote additional bleeding through development of a dilutional coagulopathy in these patients whose propensity for bleeding is increased. Contrary to hemodilution, transfusion of fresh (preferably) or reconstituted whole blood (packed red blood cells and fresh frozen plasma) is initiated early to maintain circulating blood volume, oxygen carrying capacity, plasma oncotic pressure, and normal coagulation status. Cell saver and autologous blood (when feasible) are used to maintain blood volume and reduce the need for allogeneic blood transfusion.25 The rate of complications is reported to be increased after spine surgery in patients with past medical history of cardiac surgery.6,10 Perioperative complications during scoliosis surgery in patients with CHD can be predicted by the preoperative ASA status as well as increased EBL during surgery.5 Postoperative pleural effusion has been attributed to the abnormal circulation in patients with CHD,6,8 and high venous pressure in patients with Fontan circulation likely contributes to the development of pleural fluid collections and sometimes ascites after surgery. Prolongation of hospitalization was previously February 2014

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E216

27/12/13 3:10 PM

SURGERY reported in patients with CHD who received spine surgery5,8,10; whereas, the length of hospitalization tends to be shorter in patients without CHD.26 Although the extent of surgery was less during VEPTR or GR compared with PSFI surgical procedures, length of stay in the ICU was longer in the patients who were administered VEPTR due to cardiac related complications. There was no perioperative mortality. There are limitations to this report, including small sample size, the retrospective nature, and the heterogeneity of the patients, which preclude inferential statistical analysis. In addition, care was rendered by a group of pediatric and pediatric cardiac anesthesiologists, therefore effects of individual practices could not be taken into account. However, we have described the patient characteristics, intraoperative management, and perioperative course of a relatively large number of spine surgical procedures in patients with CHD whom we categorized according to preoperative cardiovascular physiology. Although the stratification of patients with CHD was performed retrospectively, this classification was helpful to plan the perioperative management. Poor exercise tolerance or cyanosis might be red flags; however, no specific signs or symptoms would indicate the degree to which a patient with CHD is compromised by residual problems. From the orthopedic perspective, patients with CHD in need of spine intervention are part of a physiological spectrum, therefore preintervention assessment by a pediatric cardiologist and a pediatric cardiac anesthesiologist is essential to define operative risks. The surgeon can then have a detailed and individualized discussion with the patient and the family about the indications and all potential complications. The purpose of spine surgery for scoliosis in children with CHD is the same for otherwise normal children, which is to correct the scoliosis curve and provide adequate sagittal profile and we were able to achieve this in patients with CHD. Significant modifications of surgical technique were not necessary; however careful attention was given to operative time management with some operations performed by two experienced orthopedic surgeons. Spine surgical procedures using GR or VEPTR are generally considered relatively less complicated than PSFI, with lower blood loss and relatively short surgery time. However, the risk of prolonged mechanical ventilation, perioperative complications, and protracted ICU stay may be present regardless of spine surgery type.

CONCLUSION With meticulous multidisciplinary planning and execution, major spine surgery can be safely and successfully performed for patients with significant residua of congenital cardiac disease.

➢ Key Points ‰ A pediatric cardiac anesthesiologist is recommended for advance consultation for all patients with CHD. Spine

Spine Surgery in Children With CHD • Kadhim et al

‰ The risk of prolonged mechanical ventilation, perioperative complications, and protracted ICU stay may be present regardless of spine surgery type in children with CHD. ‰ Major spine surgery can be safely and successfully performed in patients with significant residua of congenital cardiac disease.

References

1. Van Biezen FC, Bakx PA, De Villeneuve VH, et al. Scoliosis in children after thoracotomy for aortic coarctation. J Bone Joint Surg Am 1993;75:514–8. 2. Ruiz-Iban MA, Burgos J, Aguado HJ, et al. Scoliosis after median sternotomy in children with congenital heart disease. Spine (Phila Pa 1976) 2005;30:E214–8. 3. Herrera-Soto JA, Vander Have KL, Barry-Lane P, et al. Spinal deformity after combined thoracotomy and sternotomy for congenital heart disease. J Pediatr Orthop 2006;26:211–5. 4. Herrera-Soto JA, Vander Have KL, Barry-Lane P, et al. Retrospective study on the development of spinal deformities following sternotomy for congenital heart disease. Spine (Phila Pa 1976) 2007;32:1998–2004. 5. Coran DL, Rodgers WB, Keane JF, et al. Spinal fusion in patients with congenital heart disease. Predictors of outcome. Clin Orthop Relat Res 1999;364:99–107. 6. Hedequist DJ, Emans JB, Hall JE. Operative treatment of scoliosis in patients with a Fontan circulation. Spine (Phila Pa 1976) 2006;31:202–5. 7. Leichtle CI, Kumpf M, Gass M, et al. Surgical correction of scoliosis in children with congenital heart failure (Fontan circulation): case report and literature review. Eur Spine J 2008;17(suppl 2):S312–7. 8. Perez-Caballero C, Sobrino E, Vazquez JL, et al. Complication of surgery for scoliosis in children with surgically corrected congenital cardiac malformations. Cardiol Young 2009;19:272–7. 9. Rafique MB, Stuth EA, Tassone JC. Increased blood loss during posterior spinal fusion for idiopathic scoliosis in an adolescent with Fontan physiology. Paediatr Anaesth 2006;16:206–12. 10. Taggart NW, Shaughnessy WJ, Stans AA, et al. Outcomes of spinal fusion in children with congenital heart disease. J Pediatr Orthop 2010;30:670–5. 11. Vischoff D, Fortier LP, Villeneuve E, et al. Anaesthetic management of an adolescent for scoliosis surgery with a Fontan circulation. Paediatr Anaesth 2001;11:607–10. 12. Keats AS. The ASA classification of physical status–a recapitulation. Anesthesiology 1978;49:233–6. 13. Soliman DE, Maslow AD, Bokesch PM, et al. Transoesophageal echocardiography during scoliosis repair: comparison with CVP monitoring. Can J Anaesth 1998;45:925–32. 14. Gillingham BL, Fan RA, Akbarnia BA. Early onset idiopathic scoliosis. J Am Acad Orthop Surg 2006;14:101–12. 15. Johnston CE, Richards BS, Sucato DJ, et al. Correlation of preoperative deformity magnitude and pulmonary function tests in adolescent idiopathic scoliosis. Spine (Phila Pa 1976) 2011;36:1096–102. 16. Weinstein SL, Zavala DC, Ponseti IV. Idiopathic scoliosis: longterm follow-up and prognosis in untreated patients. J Bone Joint Surg Am 1981;63:702–12. 17. Primiano FP, Jr, Nussbaum E, Hirschfeld SS, et al. Early echocardiographic and pulmonary function findings in idiopathic scoliosis. J Pediatr Orthop 1983;3:475–81. 18. Florentino-Pineda I, Thompson GH, Poe-Kochert C, et al. The effect of Amicar on perioperative blood loss in idiopathic scoliosis: the results of a prospective, randomized double-blind study. Spine (Phila Pa 1976) 2004;29:233–8. 19. Kiani A, Shakibi JG. Fontan physiology. Circulation 1995;92: 3148–50. 20. Jahangiri M, Kreutzer J, Zurakowski D, et al. Evaluation of hemostatic and coagulation factor abnormalities in patients undergoing the Fontan operation. J Thorac Cardiovasc Surg 2000;120:778–82. www.spinejournal.com

E217

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E217

27/12/13 3:10 PM

SURGERY 21. Odegard KC, McGowan FX, Jr, Zurakowski D, et al. Coagulation factor abnormalities in patients with single-ventricle physiology immediately prior to the Fontan procedure. Ann Thorac Surg 2002;73:1770–7. 22. van Nieuwenhuizen RC, Peters M, Lubbers LJ, et al. Abnormalities in liver function and coagulation profile following the Fontan procedure. Heart 1999;82:40–6. 23. Malcolm-Smith NA, McMaster MJ. The use of induced hypotension to control bleeding during posterior fusion for scoliosis. J Bone Joint Surg Br 1983;65:255–8.

E218

www.spinejournal.com

Spine Surgery in Children With CHD • Kadhim et al

24. Copley LA, Richards BS, Safavi FZ, et al. Hemodilution as a method to reduce transfusion requirements in adolescent spine fusion surgery. Spine (Phila Pa 1976) 1999;24:219–22. 25. Nuttall GA, Horlocker TT, Santrach PJ, et al. Predictors of blood transfusions in spinal instrumentation and fusion surgery. Spine (Phila Pa 1976) 2000;25:596–601. 26. Dhawale AA, Shah SA, Sponseller PD, et al. Are antifibrinolytics helpful in decreasing blood loss and transfusions during spinal fusion surgery in children with cerebral palsy scoliosis? Spine (Phila Pa 1976) 2012;37:E549–55.

February 2014

Copyright © 2014 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. SPINE130198.indd E218

27/12/13 3:10 PM