One of the longest documented surgeries in medical history was the separation of craniopagus twins Ganga and Jamuna Shrestha at Singapore General Hospital (SGH) in April 2001. The operation took approximately 100 hours and involved more than 100 staff members. The twins were joined at the skull and shared complex venous anatomy, making the separation an exceptionally challenging neurovascular procedure.
The operation required six months of preoperative planning, multimodal imaging, tissue expansion, virtual surgical planning, and close coordination across surgical and medical specialties. Both twins survived the separation, although their postoperative courses included significant complications.
For physicians, the case offers more than a remarkable surgical statistic. It illustrates the challenges of managing complex anatomy, prolonged operative time, multidisciplinary coordination, handoffs, fatigue, reconstruction, and outcomes that extend beyond the operating room.
Source note: Unless otherwise noted, details about the operation are based on the published case report by neurosurgeon Keith Y. C. Goh. Singapore General Hospital’s account provides additional firsthand perspective from Dr. Chumpon Chantharakulpongsa, one of the lead neurosurgeons involved in the separation.
The operation at a glance
- Patients: Ganga and Jamuna Shrestha
- Procedure: Total vertical craniopagus twin separation
- Location: Singapore General Hospital
- Date: April 2001
- Operating time: Approximately 100 hours
- Team: More than 100 SGH staff
- Preoperative planning: Six months
- Key planning tools: MRI, CT, cerebral angiography, virtual reality modeling, life-sized polymer models
- Outcome: Both twins survived the separation and returned to Nepal within six months
How long was the surgery?
The separation of Ganga and Jamuna Shrestha lasted approximately 100 hours, or about four days. Contemporary and institutional sources report slightly different durations, ranging from 97 to 103 hours. Singapore General Hospital’s current historical account describes the operation as 97 hours, while other published accounts report 103 hours. Given the discrepancy, approximately 100 hours is the most appropriate figure to use.
Why did the operation take approximately 100 hours?
Ganga and Jamuna were joined at the skull vertex and faced in opposite directions. Although the twins had separate brains, their brains were partially fused and shared complex venous and vascular connections, creating substantial neurovascular challenges during separation.
The team spent six months preparing for the procedure. Cerebral angiography, MRI, and CT were used to map the twins’ anatomy, while tissue expanders provided additional scalp tissue needed for reconstruction.
The team also used virtual reality technology and life-sized polymer models of the twins’ skulls and brains to study the anatomy and plan the separation before surgery.
The procedure itself required the team to:
- Separate shared venous structures
- Preserve cerebral perfusion
- Manage hemorrhage risk
- Monitor neurological and physiological status
- Maintain anesthesia throughout the prolonged procedure
- Reconstruct the dura, calvarium, and scalp
After separation, the surgeons reconstructed the dura, skull, and scalp using artificial dura, absorbable plates, and split-skin grafts.
The duration was therefore driven not by a single surgical step, but by the combination of complex shared anatomy, neurovascular dissection, reconstruction, physiological management, and the need to coordinate multiple specialties throughout the procedure.
What made the surgery possible?
The separation required extensive preparation and coordination before the twins entered the operating room.
Six months of preparation
The surgical team spent six months preparing for the procedure. Cerebral angiography, MRI, and CT were used to map the twins’ complex anatomy, while tissue expanders provided additional scalp tissue for reconstruction.
The team also created virtual reality models and life-sized polymer models of the twins’ skulls and brains. These tools allowed the surgeons to study the anatomy in detail and plan the sequence of separation and reconstruction before surgery.
More than 100 staff members
More than 100 Singapore General Hospital staff members participated in the operation, which lasted approximately four days. The procedure required coordination across multiple surgical and medical specialties as the team worked through separation, monitoring, anesthesia, and reconstruction.
Dr. Chumpon Chantharakulpongsa, one of the lead neurosurgeons, compared the team to “a team of mountaineers scaling Mt Everest.”
He also described the collaborative approach as:
“We were a multi-disciplinary team with kampong spirit.” — Dr. Chumpon Chantharakulpongsa, Singapore General Hospital
For a procedure of this complexity and duration, coordination was as important as technical expertise. The team needed a shared understanding of the operative plan, the twins’ evolving clinical status, and the priorities at each stage of the procedure.
How did technology support the surgery?
The Shrestha separation relied on detailed, patient-specific imaging and surgical planning tools to help the team understand the twins’ complex anatomy before the procedure.
The team used MRI, CT, and cerebral angiography to map the twins’ brains and vascular structures. They also used virtual reality modeling and life-sized polymer models to study the anatomy and plan the separation and subsequent reconstruction.
These technologies helped the surgical team:
- Map complex shared anatomy
- Identify critical vascular structures
- Plan the sequence of separation
- Anticipate technically difficult steps
- Plan cranial and soft-tissue reconstruction
The case illustrates a principle that remains relevant in complex surgery today: technology supports surgical decision-making, but it does not replace clinical expertise. Imaging, modeling, and other planning tools are most valuable when they are integrated into a coordinated clinical strategy and interpreted by the clinicians responsible for the patient’s care.
The Shrestha operation was performed more than two decades ago, but its use of patient-specific modeling and simulation foreshadowed approaches that are now increasingly used to plan complex surgical procedures.
What happened after the separation?
Both twins survived the separation and returned to Nepal within six months. Their postoperative courses, however, included significant complications.
The published case report documented:
- Focal cortical infarction
- Meningitis
- Hydrocephalus
At three months, the report described minor disability in one twin and severe developmental delay in the other.
These outcomes highlight an important consideration for physicians: operative survival is only one measure of success. For complex procedures, meaningful outcomes may also include neurological function, complications, rehabilitation needs, developmental progress, functional independence, and quality of life.
What makes an ultra-long surgery challenging?
The Shrestha operation was an extreme example, but prolonged surgery creates challenges that apply across specialties. Sustained operative time places demands on attention, decision-making, communication, and coordination across teams.
In a Sermo physician poll about prolonged surgery, 73% of participating physicians identified clinician stamina and coordination across multiple teams and shifts as the greatest challenge during ultra-long surgery.
One Sermo member, an otolaryngologist, described the challenge this way:
“Long surgeries test not only surgical skills but also discipline, resilience, and the ability to manage one’s own physical and mental resources.”
Fatigue management is therefore a team-level clinical consideration, not simply an individual responsibility. Planned staffing rotations can reduce fatigue, but transitions between clinicians also create opportunities for information loss.
For prolonged procedures, structured handoffs should preserve the team’s shared understanding of the patient’s current status, what has been completed, and what comes next. Key information includes:
- Current physiological status and active concerns
- Operative steps completed and next priorities
- Relevant anatomy already addressed
- Blood loss, fluid management, and major complications
- Medications, equipment, and other issues requiring attention
The goal is not simply to replace an exhausted clinician. It is to transfer responsibility without losing clinical context, situational awareness, or continuity of decision-making.
What types of surgery can take the longest?
In a Sermo poll, 60% of physicians said the longest surgery they had personally participated in or witnessed lasted under 6 to 12 hours, 24% reported 12–48 hours, and 7% had been involved in procedures exceeding 48 hours.
| Procedure | Factors that can extend operative time |
| Cytoreductive surgery with HIPEC | Extensive peritoneal tumor resection, multivisceral involvement, reconstruction, and the addition of intraperitoneal chemotherapy can result in procedures lasting 8–15 hours or longer. Source | Source |
| Liver transplantation | Hepatectomy, graft implantation, vascular and biliary reconstruction, bleeding risk, and complex hemodynamic management can make transplantation a prolonged procedure. Liver transplant surgery can take 12 hours or longer. Source |
| Complex neurovascular or skull-base surgery | Complex anatomy and extensive resection can prolong operative time. In one study of open skull-base surgery, procedures ranged from 6.5 to 16.7 hours, with operations exceeding 13 hours associated with increased intraoperative hemorrhage. Source |
| Microvascular reconstruction | Extensive resection followed by free-flap harvest, preparation, and microvascular anastomosis can contribute to prolonged operative times. Source | Source |
| Complex spinal deformity reconstruction | Multilevel fusion, combined approaches, osteotomies, instrumentation, and complex deformity correction can result in substantially longer operative times. Source | Source |
One general surgeon participating in the Sermo discussion recalled a 12-hour head and neck microvascular flap procedure and emphasized the emotional intelligence and team coordination required as the operation progressed.
The Shrestha separation was an exceptional case rather than a benchmark for routine surgery. Its value lies in showing how operative duration can magnify the challenges of anatomy, staffing, anesthesia, communication, monitoring, and reconstruction.
How do surgical teams prepare for prolonged procedures?
Preparation for an ultra-long operation begins well before the patient enters the operating room.
Establish a shared operative strategy
The surgical, anesthesia, and other participating teams should understand the procedural sequence, anticipated risks, individual responsibilities, key decision points, and contingency plans before the procedure begins.
Plan staffing and handoffs
Long procedures require appropriate coverage and relief. Staffing rotations should account for the clinical phase of the procedure while preserving the expertise needed at each stage. Standardized handoffs can help maintain continuity as responsibility changes.
“Staff rotation, subspecialization, improved hemodynamic monitoring and anesthetic drugs, and technological advances make long surgeries less dangerous today.” — General practitioner, Sermo member
Plan postoperative care before surgery begins
Complex prolonged procedures require postoperative planning before the first incision. ICU capacity, ventilation, neurological assessment, infection monitoring, pain management, rehabilitation, and potential further intervention should all be considered as part of the operative strategy.
One vascular surgeon on Sermo described a 10‑hour intestinal resection where the team rotated staff for breaks, monitored anesthesia and positioning to prevent complications, cycled in fresh instruments, and maintained strict infection control while planning for postoperative ICU care.
What can the longest surgeries teach physicians?
Preparation is part of the procedure
The six months of imaging, tissue expansion, anatomical modeling, and multidisciplinary planning allowed the team to anticipate technical challenges before entering the operating room.
Complex cases require shared situational awareness
More than 100 staff members participated in the Shrestha separation. The case shows that managing extreme surgical complexity depends not only on individual technical expertise but also on communication, coordination, and continuity across specialties.
Surgical success extends beyond the operating room
Both patients survived the separation, but their postoperative complications and developmental outcomes demonstrate why complex surgical outcomes should be evaluated longitudinally rather than defined solely by operative survival.
The Shrestha separation remains remarkable because of its duration. Its more enduring lessons are about patient-specific planning, technical precision, multidisciplinary teamwork, communication, and managing complexity as a clinical system.
Frequently asked questions
What was the longest surgery ever recorded?
The separation of craniopagus twins Ganga and Jamuna Shrestha at Singapore General Hospital in 2001 is widely cited as one of the longest surgeries ever performed. Sources report that the operation lasted approximately 100 hours, with reported durations ranging from 97 to 103 hours.
How long did the longest surgery take?
The Shrestha twins’ separation took approximately 100 hours, or nearly four days of operating time.
Why did the surgery take so long?
The twins were joined at the skull and shared complex venous anatomy. Their separation required extensive neurovascular dissection, neurological and physiological monitoring, anesthesia, and reconstruction of the dura, skull, and scalp.
How many people were involved in the surgery?
More than 100 Singapore General Hospital staff members were involved in the procedure, according to SGH’s account.
What types of surgery can take the longest?
Cytoreductive surgery with HIPEC, liver transplantation, complex neurovascular or skull-base surgery, microvascular reconstruction, and complex spinal deformity reconstruction can all require prolonged operating times depending on the individual case.
How do surgical teams manage fatigue during long surgeries?
Teams can manage fatigue through planned staffing rotations, structured handoffs, appropriate specialty coverage, and strategies that maintain continuity of clinical decision-making throughout the procedure.
Continue the clinical conversation on Sermo
The Shrestha case demonstrates what is possible when complex anatomy, advanced planning, technical expertise, and multidisciplinary teamwork come together.
But physicians continue to face prolonged and complex procedures across specialties.
What is the longest operation you’ve participated in? How did your team manage fatigue, staffing, handoffs, and patient safety?
Share your experience and compare approaches with verified healthcare professionals across specialties and geographies.
