Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Operative Management of Perinatal Lumbar Disc Herniation and Cauda Equina Syndrome: A Case Series

Introduction Perinatal lumbar discectomy for lumbar disc herniation or cauda equina syndrome is a rare clinical scenario. This case series outlines the surgical management of this clinical scenario at a national tertiary referral centre over a 10-year period Methods A retrospective review of all females who underwent discectomy / decompression for lumbar disc herniation or cauda equina syndrome in the perinatal period at a national tertiary referral centre for spine surgery over a 10-year period between January 2008 to December 2017. Results 6 cases required surgical intervention. All patients were successfully managed with surgical decompressive procedures and recovered well in the postoperative period without complication. Conclusions The principles of management remain the same in the pregnant and non-pregnant populations, although treatment options are complicated by the desire to avoid risk to the developing foetus. Surgical intervention is safe to both mother and baby and if performed promptly is associated with an excellent functional outcome.

Review of Time to Surgical Decompression in Traumatic Spinal Cord Injured Patients

Interventions which may improve neurological outcomes, including time to surgical decompression, in traumatic spinal cord injury (TSCI) evoke much interest. The majority of TSCI patients in Ireland are managed acutely at the National Spinal Injuries Unit (NSIU). A retrospective review of healthcare records of TSCI patients, who had surgical management there, in 2010, 2011, 2012, was performed. From the information gathered, the duration of each stage of the patient pathway was calculated. Median duration between onset of injury and time of arrival at local hospital was 1 hour 25 minutes, between arrival at local hospital and referral to NSIU was 4 hours 17 minutes, between referral to and arrival at NSIU was 6 hours 25 minutes, between onset of injury and arrival at NSIU was 13 hours 7 minutes, between onset of injury and surgical decompression was 27 hours. A number of factors have been identified which could influence these time durations.

Spinal injuries in Irish rugby: a ten-year review

This study assessed the frequency of acute injury to the spinal cord in Irish Rugby over a period of ten years, between 1995 and 2004. There were 12 such injuries; 11 were cervical and one was thoracic. Ten occurred in adults and two in schoolboys. All were males playing Rugby Union and the mean age at injury was 21.6 years (16 to 36). The most common mechanism of injury was hyperflexion of the cervical spine and the players injured most frequently were playing at full back, hooker or on the wing. Most injuries were sustained during the tackle phase of play. Six players felt their injury was preventable. Eight are permanently disabled as a result of their injury.

Outcome of calcaneal fractures treated operatively and non-operatively. the effect of litigation on outcomes

BACKGROUND

The optimum management of calcaneal fractures is controversial. These injuries are frequently associated with compensation litigation, which effects the outcome.

AIMS

To assess the outcome of operatively and conservatively managed intra-articular calcaneal fractures and to examine the effect of compensation litigation on outcome.

METHODS

This was a retrospective study of calcaneal fractures from a single regional trauma unit, with management decided by the admitting consultant surgeon's preference. Fifty-four patients (33 operative, 21 conservative) with an average follow-up of 40 months (range 14-78 months) were reviewed. Sixteen patients (30%) were pursuing a compensation case resulting from the injury.

RESULTS

Despite similar fractures, medical co-morbidity and trauma energy, significantly worse outcome scores were seen in litigants (p < 0.0001). Footwear fitting problems were greater in litigants. Time off work was more than twice that of non-litigants (14.5 vs 6 months, p < 0.01). Results were similar between the operative and non-operative groups in terms of functional score, footwear problems and time off work.

CONCLUSIONS

Litigation was the major determinant of outcome following calcaneal fracture repair; highlighting the unreliability of subjective evaluation in determining outcome in the face of litigation. No subset of patients appeared to significantly benefit from internal fixation of their fracture.

Old principles revisited--traction splinting for closed proximal phalangeal fractures

Proximal phalangeal fractures are commonly caused by a blunt injury to the dorsum of the hand. This typically results in a closed transverse fracture with volar angulation, which is an inherently unstable fracture pattern. K-wiring and internal fixation have the disadvantage of damage to the soft tissue envelope, risk of infection and wire loosening. We describe 15 patients treated with an alternative method of skin traction and splintage in our regional trauma centre. Fractures were reduced under X-ray and reduction was maintained using a combination of a malleable metal splint and tape to provide skin traction. Fourteen patients had an excellent objective and subjective outcome. The advantage of our technique is preservation of the soft tissue envelope and it should be considered an alternative to other treatment options as it is simple, quick, inexpensive and non-invasive.

Instrumented posterolateral lumbar fusion using coralline hydroxyapatite with or without demineralized bone matrix, as an adjunct to autologous bone

BACKGROUND CONTEXT

Autogenous posterolateral fusion with and without instrumentation has been reported with good results. However, difficult-to-fuse patients, such as smokers, elderly patients with poor bone quality and/or quantity, or patients with prior posterior surgeries, may have somewhat lower fusion rates.

PURPOSE

To determine the efficacy of coralline hydroxyapatite with or without demineralized bone matrix as a bone graft extender in a human clinical model with long-term follow-up.

STUDY DESIGN/SETTING

A retrospective series of 40 patients undergoing instrumented autogenous posterolateral lumbar fusion augmented with coralline hydroxyapatite with or without demineralized bone matrix.

PATIENT SAMPLE

Long-term clinical and radiographic follow-up were examined for 40 patients who underwent an instrumented posterolateral fusion only. Patients undergoing anterior lumbar interbody fusion (ALIF) procedures were not considered part of the sample.

METHODS

All patients underwent successful transpedicular fixation with autogenous posterolateral lumbar fusion. Fifteen cc of Pro Osteon 500 coralline hydroxyapatite (Interpore Cross International, Irvine, CA) was used at each level. An additional 10 cc of Grafton demineralized bone matrix gel (Osteotech, Eatontown, NJ) was used in 70% of these patients.

RESULTS

An overall fusion rate of 92.5% was achieved. Pain and function improvement were good but somewhat age dependent and correlated with the number of comorbidities. Patients with Grafton DBM gel had a lower fusion rate of 89.3%.

CONCLUSIONS

Based on this small retrospective review, coralline hydroxyapatite is an effective bone graft extender in difficult-to-fuse patients as an adjunct to autologous bone for posterolateral fusion of the lumbar spine when combined with rigid instrumentation.

Gasless endoscopic anterior lumbar interbody fusion utilizing the B. E.R.G. approach

BACKGROUND

Several authors have reported success using a gas-mediated transperitoneal approach for lumbar interbody fusion. However, this approach has not been shown to reliably and predictably address segments above L4-5.

METHODS

The B.E.R.G. approach was attempted in 202 patients who required anterior lumbar interbody fusion (ALIF). Of those, 168 were completed successfully without conversion to an open procedure. The anterior retroperitoneal approach required no gas insufflation. The gasless environment allowed for the use of standard anterior instrumentation and a variety of fusion grafts and devices.

RESULTS

Mean hospital stay was 1.95 days, with 73% of patients discharged in <47 h following surgery. Clinical results from the first 50 patients, with a minimum 2-year follow-up, include a 92% fusion rate and 78% of patients reporting significant pain relief of greater than 50%.

CONCLUSIONS

The B.E.R.G. approach offers significant technical advantages over the standard gas-mediated transperitoneal approach for ALIF. The clinical results are similar to those reported for open approaches and the gas-mediated transperitoneal approach.

Minimally invasive 360 degrees instrumented lumbar fusion

A retrospective preliminary study was undertaken of combined minimally invasive instrumented lumbar fusion utilizing the BERG (balloon-assisted endoscopic retroperitoneal gasless) approach anteriorly, and a posterior small-incision approach with translaminar screw fixation and posterolateral fusion. The study aimed to quantify the clinical and radiological results using this combined technique. The traditional minimally invasive approach to the anterior lumbar spine involves gas insufflation and provides reliable access only to L5-S1 and in some cases L4-5. A gas-mediated approach yields many technical drawbacks to performing spinal surgery. A minimally invasive posterior approach involving suprafascial pedicle screw instrumentation has been developed, but without wide-spread use. Translaminar facet fixation may be a viable alternative to transpedicular fixation in a 360 degrees instrumented fusion model. Past studies have shown open 360 degrees instrumented lumbar fusion yields high arthrodesis rates. The study examined the cases of 46 patients who underwent successful 360 degrees instrumented lumbar fusion using a combined minimally invasive approach. Anterior lumbar interbody fusion (ALIF) at one or two levels was performed through the BERG approach; a gasless retroperitoneal approach to the lumbar spine allowing the use of standard anterior instrumentation. Posteriorly, all patients underwent successful decompression, translaminar fixation, and posterolateral fusion at one or two levels through one small (2.5-5.0 cm) incision. Results showed mean hospital stay of 2.02 days; mean combined blood loss was 255 cc; and mean pain relief was 56%, with 75.5% of patients reporting good, excellent, or total pain relief. Forty-two of 46 patients (93.2%) achieved a solid fusion 24 months after surgery. A total of 47% of all patients working prior to surgery returned to work following surgery. The study showed that minimally invasive 360 degrees instrumented lumbar fusion, when performed utilizing these approaches, yields a high rate of solid arthrodesis (93.3%), good pain relief, short hospital stays, low blood losses, accelerated rehabilitation, and a quick return to the workforce. The BERG approach offers technical advantages over the traditional gas-mediated laparoscopic approach to the anterior lumbar spine.

Anterior interbody fusion of the cervical spine with coralline hydroxyapatite

STUDY DESIGN

A nonrandomized, retrospective human study of patients requiring anterior discectomy and reconstruction from C3 to T1. The pattern of incorporation, presence or absence of disc space collapse, maintenance of correction, and clinical outcomes were considered.

OBJECTIVE

To determine the efficacy of coralline hydroxyapatite as a bone replacement in anterior interbody fusions of the cervical spine used in conjunction with rigid plate fixation.

SUMMARY OF THE BACKGROUND DATA

Autograft is the gold standard for anterior interbody fusion of the cervical spine. Reported complication and morbidity rates with the use of autograft are as high as 21%. Using allograft instead of autograft presents numerous problems including lower rates of fusion. Other bone substitutes such as ceramics and polymethylmethacrylate are ineffective for fusion.

METHODS

Twenty-six skeletally mature patients underwent anterior decompression, stabilization, microdiscectomy, and reconstruction with Pro Osteon 200 (Interpore Cross International, Irvine, CA) coralline hydroxyapatite and AO anterior cervical locking plates. Iliac crest autograft, local bone, and allograft were not used.

RESULTS

The minimum follow-up period was 2 years (average, 30 months). There was no evidence of plate breakage, screw breakage, resorption of the implant, or pseudarthrosis. Two patterns of incorporation were identified. The implant incorporated totally in 100% of the disc spaces. Average hospital stay was 1.6 days. The average decrease in pain was 75.8%. There was no evidence of nonunion.

CONCLUSIONS

The use of Pro Osteon 200 with rigid anterior plating seems promising as a bone replacement in the cervical spine. The incorporation rate is exceedingly high, and the complication rate nonexistent.

Four year experience with the AO Anterior Thoracolumbar Locking Plate

For decades spinal surgeons have attempted to design simple, single stage anterior internal fixation systems for the thoracic and lumbar spine. Early devices presented both biomechanical and technical problems. The AO Anterior Thoracolumbar Locking Plate (ATLP) was designed to solve some of the problems encountered with early anterior instrumentation. The ATLP system is constructed in Commercially Pure titanium. It is a low profile device indicated for use for unstable burst fractures in the anterior column; metastatic tumor management; and degenerative diseases of the thoracolumbar spine between levels T10 and L5. Implantation of the device involves direct anterior decompression with sagittal reduction and corpectomy. This is followed by grafting reconstruction, and plate fixation. This device has been implanted in 25 patients with an average follow-up of 38 months. There were five (5) broken screws in three (3) patients, and no broken plates. Implant related postoperative complications included two misplaced screws. Preliminary results indicate that the ATLP system seems to be a safe, low profile, MRI/CT compatible device that provides definitive single stage fixation of the anterior spinal column.

Management of metastatic tumors to the spine using simple plate fixation

Frequency of metastasis to the spine in the population of patients suffering from malignant disease is a significant clinical problem, as these patients present with intractable pain and neurologic impairment. The sequelae of metastatic tumors to the spinal column significantly decrease the quality of the patient's life. With the advent of modern chemotherapeutic regimens in metastatic disease, patients with metastatic tumors are living longer and more productive lives. The goal of surgical management of this problem is to increase the quality of the patient's life, and not longevity. The immediate technical goals are resection of the pathological segment, restoration of load bearing capacity for mobilization of the patient, and decompression of compromised neural structures, as well as maintenance of spinal stability to decrease pain and increase the patient's quality of life during the terminal stages. This is a series of 28 patients with metastatic tumors to the spine, with an average age of 61.5 years, ranging from 25-81 years of age. Within this population there were 11 different tumor types. The postoperative survivorship was an average of 6.4 months. Twenty patients in this series had an anterior procedure alone using a combination of Methylmethacrylate and inexpensive plate fixation. Six patients required an anterior/posterior procedure for circumferential spinal compression and instability. These techniques provide immediate spinal stability for rapid mobilization of the patient. Twenty-four patients in the series had significant pain relief, and 17 experienced neurologic improvement.(ABSTRACT TRUNCATED AT 250 WORDS)