Risks of Surgery Without Pre-operative Transfusion in Sickle Cell Disease
Proceeding to surgery without pre-operative transfusion in sickle cell disease patients significantly increases the risk of life-threatening complications including vaso-occlusive crisis, acute chest syndrome, stroke, and death—with outcomes heavily dependent on surgical risk category and baseline hemoglobin level. 1, 2
Risk Stratification by Surgical Complexity
The decision to proceed without transfusion must be guided by surgical risk category:
Low-Risk Procedures
- Eye, skin, ear, distal extremity, dental, perineal, and inguinal surgeries can be performed without pre-operative transfusion if baseline hemoglobin is ≥90 g/L, though a modest residual risk remains. 2
- These procedures carry acceptable complication rates when meticulous peri-operative care is maintained. 1
Moderate-Risk Procedures
- Throat, neck, spine, proximal extremity, genitourinary, and intra-abdominal surgeries (including caesarean section, splenectomy, cholecystectomy, hip replacement) are associated with significantly higher complication rates when performed without transfusion. 2
- Proceeding without transfusion for moderate-risk surgery is strongly discouraged by current guidelines. 2
- Tonsillectomy/adenoidectomy carries particularly high risk, with postoperative complications occurring in 56% of cases without transfusion, predominantly pulmonary complications. 3
High-Risk Procedures
- Any surgery with substantial physiologic stress requires exchange transfusion targeting hemoglobin of 100 g/L regardless of baseline hemoglobin or genotype. 2
- Performing high-risk operations without transfusion is strongly contraindicated. 2
- Cardiac surgery, major orthopedic procedures, and operations requiring cardiopulmonary bypass fall into this category. 1
Specific Peri-operative Complications Without Transfusion
Vaso-occlusive Crisis
- The most common peri-operative complication, precipitated by hypoxia, hypothermia, acidosis, dehydration, and pain—all frequently encountered during surgery. 2, 4
- The risk persists throughout the peri-operative period, with most events occurring postoperatively. 2
- In one study, postoperative sickle cell crisis occurred in 4.3% of patients who received no transfusion versus 9.5% with simple transfusion and 22.2% with exchange transfusion. 5
Acute Chest Syndrome
- Develops in over 50% of hospitalized patients with vaso-occlusive crisis and represents a life-threatening emergency. 4
- May develop rapidly after surgery and mandates immediate escalation to intensive care. 2
- Occurs in approximately 10% of surgical patients regardless of transfusion strategy, with pulmonary disease history and higher surgical risk as significant predictors. 6
- Postoperative acute chest syndrome occurred in 4.3% of non-transfused patients in one series. 5
Stroke
- Any acute neurologic symptom beyond transient mild headache requires urgent evaluation. 2, 4
- Affected patients may need emergency exchange transfusion. 2
- Children under 17 years should have transcranial Doppler results available from within the previous 12 months before elective procedures. 4
Infection and Sepsis
- Patients have functional hyposplenism, predisposing them to bacterial infections from encapsulated organisms. 2
- Heightened vigilance for gram-negative sepsis, urinary tract infection, biliary sepsis, and non-typhi salmonella infection is required. 4
- Temperature ≥38.0°C mandates blood cultures and empiric broad-spectrum antibiotics. 7, 4
Mortality Risk
- Overall 30-day mortality after surgery in sickle cell patients is 1.1% (with 0.3% directly attributable to the surgical/anesthetic event), substantially higher than the general surgical population. 2
- Maternal mortality among pregnant patients with sickle cell disease undergoing surgery is 1–3%, far exceeding the rate in the general obstetric population. 2, 1
- Two deaths from acute chest syndrome were reported in a major randomized trial of 604 operations. 6
Evidence on Transfusion vs. No Transfusion
Randomized Trial Data
- The landmark Preoperative Transfusion in Sickle Cell Disease Study (604 operations) found that conservative transfusion (targeting Hb 10 g/dL) was as effective as aggressive transfusion (targeting HbS <30%) in preventing complications, with 31% serious complications in the aggressive group versus 35% in the conservative group. 6
- However, this study compared two transfusion strategies—not transfusion versus no transfusion. 6
Observational Data on No Transfusion
- A pediatric series of 66 elective procedures without transfusion reported 26% overall complication rate, with complications more likely after thoracotomy/laparotomy (50%) and tonsillectomy/adenoidectomy (56%) versus other procedures (5%). 3
- Another study found that all patients who developed postoperative complications had preoperative HbS >40%, suggesting that higher sickle hemoglobin percentages carry increased risk. 5
- A systematic review concluded that available studies were underpowered to detect a treatment effect comparing transfusion to no transfusion. 8
Critical Management Requirements When Transfusion Not Used
If surgery must proceed without transfusion, the following are mandatory:
Pre-operative Requirements
- Baseline hemoglobin must be ≥90 g/L for low-risk procedures; lower levels require simple top-up transfusion to 100 g/L. 1, 2
- Patient must be at clinical and hematologic steady state—no fever, no active painful crisis. 1, 4
- Cross-matched blood must be available on site even if transfusion is not planned, for immediate use if needed. 2
- Schedule patients early on the operating list to avoid prolonged starvation. 1
Intra-operative Vigilance
- Meticulous avoidance of hypoxia, hypothermia, acidosis, and dehydration—the four cardinal triggers of sickling. 1, 9
- Maintain oxygen saturation above baseline or 96% (whichever is higher) with continuous monitoring. 4
- Ensure normothermia with active warming measures, as hypothermia leads to peripheral stasis and increased sickling. 4, 9
- Aggressive fluid management to prevent dehydration, with careful monitoring to avoid overhydration. 4, 9
Post-operative Monitoring
- Low threshold for ICU/HDU admission, as the majority of complications occur postoperatively. 1, 2
- Continuous oxygen monitoring until saturation maintained at baseline in room air. 4
- Incentive spirometry and chest physiotherapy every 2 hours to prevent acute chest syndrome. 4, 9
- Early mobilization and thromboprophylaxis for all post-pubertal patients due to increased DVT risk. 4
- Daily assessment by a hematologist to monitor for sickle complications. 7
Critical Pitfalls to Avoid
- Do not proceed without transfusion for moderate- or high-risk surgery unless there is an absolute contraindication to transfusion and the surgery is life-saving. 2
- Do not operate during a painful crisis or if the patient is febrile, as this dramatically increases complication risk. 1, 4
- Do not assume that exchange transfusion is superior to simple transfusion—evidence shows exchange transfusion results in 2.4 times more transfusion-related complications without reducing surgical complications. 6, 8
- Do not delay emergency surgery for transfusion if baseline Hb is ≥90 g/L and the procedure is low-risk; proceed and transfuse intra- or postoperatively if needed. 1, 2
- Do not ignore the need for multidisciplinary coordination—a nominated lead hematologist must be involved in all surgical decisions for sickle cell patients. 1
Special Populations
Pediatric Patients
- Children under 5 years with severe obstructive sleep apnea undergoing adenotonsillectomy are at particular risk of postoperative oxygen desaturation and may require ICU/HDU admission. 1
- A nasopharyngeal airway placed under direct vision by the ENT surgeon can avoid postoperative hypoxia and reduce ICU admission need. 1