Patient injuries in the treatment of superficial venous insufficiency registered in Finland between 2004 and 2017

Abstract

Objectives

This study aimed to identify the unintended incidents that led to patient injuries (PIs) in the treatment of superficial venous insufficiency (SVI).

Methods

PI claims filed with the Finnish Patient Insurance Centre between 2004 and 2017 involving SVI were reviewed. Factors contributing to PI were identified and classified.

Results

Eighteen (13.2%) of 136 compensated PIs in the specialty of vascular surgery were related to SVI. Only 4.7% of 383 SVI claims were compensated. The incidence of PIs was 9.9 per 100 000 patients. Fifteen patients had open surgery (83.3%) and three (16.7%) endovenous treatment. Two (11.1%) patients had necrotising fasciitis, four (22.1%) had deep vein injuries and two (11.1%) had a permanent nerve injury. Two (11.1%) patients had retained endovenous material that required surgical removal.

Conclusions

PIs were identifiable during all stages of care, perioperative injuries related to open surgery being the most common.

Keywords

Superficial venous insufficiency varicose veins complication injury thermal ablation laser high ligation stripping GSV SSV

Introduction

Superficial venous insufficiency (SVI) is a condition that affects 30-40% of the adult population.¹ The treatment aims to improve the quality of life and to prevent disease progression in the patient. The treatment of SVI in the 21^st century has undergone a major shift towards endovenous treatments, which in turn affects the type and frequency of adverse events.^1–4

The level of complexity of SVI is determined by clinical classes (C1-C6). According to clinical, etiological, anatomical, pathophysiological (CEAP) classification⁵ uncomplicated disease (C1-C3) comprises 80% of these.⁶ The prevalence of the complicated disease C4-C6 is 20%. Healed or open venous ulcers affect 1% of patients.⁷

In Finland, the treatment for SVI is recommended and reimbursed, when the patient has symptomatic C2-C6 disease with ultrasound verified truncal reflux. A pre-operative duplex ultrasound is mandatory.^2,8 Nowadays, a majority of patients in Finland are treated ambulatorily by endovenous means, including thermal ablation, laser ablation (EVLA), radio frequency ablation and foam sclerotherapy (FS).⁹

The Finnish Institute of Health and Welfare keeps a record of all performed surgical procedures. The total number of performed SVI procedures in Finland is currently stable at about 13000 per year. According to THL records high ligation and stripping was the commonest procedure performed in 2006 (n = 12290), and the number of sclerotherapies (n = 385) increased in the same year. The first thermoablation was performed in 2007. In 2017, 4085 open surgical and 9029 endovenous procedures were carried out.⁹ Due to limitations in available statistics from National Institute of Health and Welfare it is not possible to give a precise number of different type of endovenous procedures annually.

In order to manage the risks involved in the treatment of SVI, knowledge about patient injuries (PIs) gives valuable information.¹⁰ Reviewing PIs facilitates recognition of the processes behind the injuries to enable their reparation and to prevent their future occurrences.^11,12

Finland’s patient insurance compensation criteria

In Finland The Patient Injuries Act (Potilasvahinkolaki 585/1986) obliges all official health care providers to have patient insurance. The Patient Insurance Centre (PIC) insures all patients, handles claims, and allocates compensations. The Patient insurance center’s function is not to determine the guilty party but only provide fair compensation to the injured patient.¹³

Health care professionals must guide patients to submit a claim to PIC for a suspected PI. Only the cases that fulfil criteria described in the abovementioned Patient Injuries Act can be compensated by the PIC. The Patient Injuries Act can be applied, when a patient has sustained a bodily injury as a result of medical treatment or health care. Seven compensation categories in the above mentioned patient insurance act are treatment injury, infection injury, accident injury, equipment-related injury, injury arising from damage to the treatment premises or the equipment used for the treatment, injury due to incorrect supply of pharmaceuticals, and unreasonable injury.¹³

Treatment injury is the most typical compensated injury. A compensable treatment injury is a bodily injury, which was caused by an examination, treatment or other similar action performed on the patient, or the failure to do so. In order to receive compensation, it must be probable that an experienced medical professional would have acted differently thereby avoiding the injury. In all infection injuries an 'infection tolerance evaluation' is required. In a more advanced stage of disease or with significant co-morbidities, more severe side-effects or unexpected outcomes are accepted. Unreasonable injury can be compensated, if it caused disproportionate consequences compared to the initial situation.¹³

Aims

The first aim of this study was to identify the frequency and the type of compensated PIs in Finland and identify any possible systemic incidents that had led to these injuries when treating SVI. A second aim was to identify how the change in treatment modalities had affected the PIs.

Material and methods

The design of the study is a retrospective analysis of Finnish national patient insurance charts of accepted and compensated PI claims, and also summaries of non-compensated claims in the treatment of SVI.

Data

The records of all closed and compensated claims concerning vascular surgery between 1 January 2004 and 31 December 2017, a 14-year period, were searched from the nationwide PIC registry. For the present study, only injuries involving SVI are reported. An analysis of summaries of non-compensated SVI claims was also performed.

Methods

All medical records, expert assessments, and compensation decisions of the compensated claims underwent a review by two vascular surgeons. Patients’ ages and sex in addition to information about health care providers and institutions were analysed. The type of operations and the indicated re-operations were recorded as well. For non-compensated patients no patient files were available for analysis but only a short summary of patients’ case and claim decision.

The care-flow process of the patient and incidents and errors that contribute to injury were analysed. One or two significant incidents were identified and classified. The structure of the classification was based on the classification originally presented by Shah et. al and modified previously by the authors.^14,15

Statistical analysis

These study data are given as categorical variables, frequencies, and percentages. As no hypothesis was formulated no statistical testing was performed.

Ethical considerations

All information regarding patients’ identities were excluded from these data. The study protocol and data search were approved by the University of Turku and by the PIC. The PIC is an insurance company, therefore it is legally obligated to provide researchers with data from its archives without separate patient consent. Identifying individual patients or hospitals is, however, highly unlikely due to the long study period. No separate approval for this study was required from the Ethics committee as this study was a retrospective analysis of insurance charts.

Results

Compensated PIs involving SVI made up 18 (13.2%) of 136 compensated patient injuries in the specialty of vascular surgery during the 14-year study period (Figure 1). Of the eighteen compensated injuries sixteen (88.9%) were compensated as treatment injuries and two (11.1%) as unreasonable injuries. As the total number of performed SVI procedures performed in Finland has remained stable at about 13000 per year, the incidence of patient injuries in SVI treatment was 9.9 per 100 000 patients.⁹

Figure 1.

The number (N) of non-compensated and compensated patient injury claims involving treatment of SVI by year (2004-2017 inclusive). There were 383 claims in total of which 18 (4.7%) claims were compensated as patient injuries.

The mean age of the injured patients was 48.6 years ± SD 9.6 (range 30-67 years). Five (27.8%) of these patients were men and thirteen were (72.2%) women.

All operations, injuries and re-operations due to injury are presented in Table 1. All operations were elective. Fifteen (83.3%) operations involved open surgery, two (11.1%) endovenous laser ablation and one (5.5%) sclerotherapy. Twelve (66.7%) patients were treated for greater saphenous vein (GSV) insufficiency, one (5.5%) for smaller saphenous vein (SSV) insufficiency and one (5.5%) for both. For four patients (22.2%) no procedure for determined truncal insufficiency was performed.

Table 1.

Patient injuries in treatment of venous insufficiency in Finland for 2004 to 2017 inclusive.

Patient no.	Operation year	CEAP	Operation	Patient injury	Consequence
1	2003	NA	HL+S GSV, phlebectomy	Failure to remove all varices	Re-surgery
2	2004	C2	HL+ S GSV, phlebectomy	Failure to treat GSV insufficiency	Re-surgery
3	2005	C3	HL+S GSV, phlebectomy	Failure to remove all varices	Re-surgery
4	2005	C4	HL+ S SSV, phlebectomy	Popliteal vein injury, postoperative infection	Intraoperative hemorrhage, severe allergic reaction to antibiotic powder
5	2005	C4	Phlebectomy, inguinal exploration	Failure to treat SSV insufficiency	Re-surgery
6	2005	C4	HL+ S GSV, phlebectomy	Pressure ulcer from dressings	Prolonged wound healing
7	2005	C4	Phlebectomy	Failure to notice GSV insufficiency	Re-surgery
8	2006	C2	HL+ S GSV, phlebectomy	Peroneal nerve damage	Nerve pain
9	2007	C4	HL+S GSV, phlebectomy	Femoral nerve damage	Nerve pain
10	2009	C2	EVLA	Retained guidance catheter	Re-surgery
11	2009	C4	HL+S GSV, phlebectomy	Necrotizing fasciitis	Multiple re-surgeries
12	2009	C4	Phlebectomy, inguinal exploration	Femoral vein ligation	Intra-operative hemorrhage and suturation
13	2010	C2	HL+S GSV, HL+S SSV, phlebectomy	Necrotizing fasciitis	Multiple re-surgeries
14	2010	C2	EVLA	Retained guide wire	Re-surgery
15	2011	C3	HL+S GSV, phlebectomy	Femoral vein injury	Intra-operative hemorrhage and correction
16	2011	NA	HL+ S GSV, phlebectomy	Femoral vein partial removal	Intra-operative hemorrhage and correction
17	2014	C4	Sclerotherapy	Failure to treat all venous insufficiency	Re-sclerotherapy
18	2014	NA	HL+ S GSV, perforator ligation, phlebectomy	Failure to close up wounds	Prolonged wound healing

HL+S: high ligation and stripping; GSV: great saphenous vein; SSV: small saphenous vein; EVLA: endovenous laser ablation; CEAP: Clinical, Etiological, Anatomical and Pathophysiological classification⁵; NA: not available.

The incidents leading to injury classified by a care-flow basis are presented in Table 2. Majority of operations were carried out by either fully trained vascular surgeons or vascular surgeons in training either in university or central hospital. Characteristics of health care providers and operations are listed in Table 3.

Table 2.

Incidents and errors leading to patient injuries in treatment of venous insufficiency classified by care flow basis.

	Incident 1		Incident 2^a
	N	%	N	%
Outpatient care
Delay or error in diagnosis or treatment	0		0
Injury in surgical outpatient procedures	0		0
Other error in outpatient care	0		0

Operative care
Preoperative judgement and surgical planning
Incorrect/unnecessary procedure or technique	2	11.1	0
Other error in preoperative care	0		0
Delay in preoperative care	0		0
Operative unit
No prophylactic antibiotic	0		0
Problems in anesthesia procedures	0		0
Wrong site surgery	0		0
Nerve lesion	2	11.1	0
Injury to other adjacent anatomical structure	3	16.7	1	5.6
Incomplete surgery	4	22.2	1	5.6
Other errors in surgical technique	1	5.6	0
Hemostatic problem	0		0
Retained gauze/instrument	2	11.1	0
Equipment related errors	0		1	5.6
Charts or instructions insufficient	0		0
Other error in procedure	0		0
Postoperative period
Postoperative ward care	0		0
Wrong/insufficient medication	0		0
Infection	3	16.7	2	11.1
Hemorrhage	0		0
Postoperative treatment/control insufficient	1	5.6	0
Retained foreign body	0		0
Unintended result	0		0
Total	18	100	5	21.7

N: number; % = proportion.

^aIn five patients, two independent errors contributed to the patient injury.

Table 3.

Characteristics of health care providers and operations in 18 patient’s injuries in treatment of superficial venous insufficiency for 2004 and 2017 inclusive.

Medical unit	N	%
University or central hospital	9	50.0
Local hospital	3	16.7
Primary care	1	5.6
Private sector	5	27.8
Education of physician
Vascular surgeon	5	27.8
Vascular surgeon in training	6	33.3
Surgeon of other specialty	7	38.9
Operation specifics
Preoperative ultrasound performed	13	72.2
Bilateral surgery	5	27.8
Reintervention	5	27.8

N: number; %: proportion.

During the study period patients reported in the injury claims 25 deep vein thrombosis and 9 pulmonary embolisms. Only one deep vein thrombosis involved a compensated patient but the reason for compensation in that case was nerve damage not thrombosis. None of the other claims with venous thromboembolism led to compensation.

Consequences of the injuries

None of the PIs involving treatment of SVI were fatal. Three patients had an injury to the femoral vein and one to the popliteal vein. All deep vein injuries were noticed intraoperatively and repaired promptly. In one patient the peroneal nerve and in another patient the femoral nerve was damaged intraoperatively which caused permanent disability and significant pain. Failure to close one patient’s (patient 18) operating wound led to delayed wound healing. A pressure wound caused by a compression bandage (patient 6) healed without operative intervention.

Two patients had retained foreign material after EVLA. In one patient (patient 10), the guidance sheath was retained, and in the other (patient 14) the guide wire was left inside the vein. Both patients had experienced pain, discomfort and walking difficulties. A significant delay occurred in the diagnosis and the subsequent removal of these foreign materials. The first patient had to wait for diagnosis and treatment for six months and the other for 14 months. Both patients required a surgical operation to remove the foreign material from the GSV.

A total of five patients suffered from an infection injury after open surgery. Two patients (patients 11 and 13) developed necrotising fasciitis. Both patients required prolonged intensive ward care, hyperbaric oxygen treatment and several re-operations. These two patients received compensation under ‘the unreasonability principle’. Three milder wound infections were not compensated merely for infection damage but they also had other causes that justified compensation. One of the postoperative infections (patient 4) was treated in primary care by bacitromycin powder which caused a severe allergic reaction.

Six patients (33.3%) required additional operations to treat SVI for either an unsatisfactory or an inadequate end result of the primary operation. One (5.6%) patient required a re-operation to treat insufficient GSV due to a lack of preoperative ultrasound examination. Another patient required repeated FS as the first one failed to alleviate any symptoms. No preoperative ultrasound had been performed. In two patients (patient 2 and 5), SVI had been correctly diagnosed with ultrasound but incomplete surgery led to re-operation to remove the GSV in one patient and the SSV in the other. Two patients (patients 1 and 3) had re-surgery to remove the remaining varicose veins.

Discussion

Compensated PIs mostly involved open SVI surgery. Injuries were caused by typical complications and by shortcomings in surgical processes. The numbers of filed claims have been on a steady decline in Finland.

Claims and decisions

In Finland, 13.2% of the accepted claims in vascular surgery between 2004 and 2017 inclusive involved SVI. Remarkably low percentage of SVI claims was accepted as only 4,7% of them were compensated. In the United Kingdom (UK), 48% of accepted claims in vascular surgery involved the treatment of varicose veins although this was for an earlier period from April 1995 to April 2007.¹⁶ In Sweden, 32% of claims in vascular surgery from 2002 to 2007 involved varicose veins of which 38% were accepted making them the likeliest group to receive compensation after injury.¹⁷ In Catalonia, 53.8% of claims in vascular surgery from 1986 to 2009 involved varicose veins and 43.5% of these claims were accepted.¹⁸

Even though the number of submitted claims in Finland was on a steady decline over the 14-year study period, the number of compensated claims has varied only slightly as annually 0-3 claims were compensated. The incidence of SVI related compensated PIs in Finland was significantly lower than in the Netherlands where less than 7 injuries were compensated yearly per 20 000 operations, the calculated incidence of compensated injuries was less than 35 per 100 000.^9,19 In Sweden, the incidence of claims was 0.18% and the incidence of accepted claims 68 per 100 000.¹⁷ Compensation criteria vary between countries, which must be considered when comparing results.

Compensation sums paid for patient injuries in Finland are confidential and cannot therefore be published. As patients only receive compensation for actual costs that incurred due to injury the compensation sums tend to be low compared to UK.¹⁶

In the treatment of diseases for other specialties, the numbers of filed claims have not decreased at the same rate in Finland.^11,12 The percentage of compensated SVI claims was lower than for the treatment of peripheral arterial disease (PAD) patients in Finland for whom 9.6% of PAD treatment claims were compensated.¹² The low proportion of compensated SVI injuries is probably because PIC compensation criteria excludes likely and typical complications such as deep vein thrombosis, localized infection or unsatisfactory cosmetic result.¹³ Compensation is also not paid for injuries with minor consequences. As only short case summaries were available for non-compensated patients no detailed analysis was able to be done for the exact reasons why the claim was not compensated.

Patients and the disease

Interestingly, 72.2% of PIs involved women. Similar results have been reported in the Netherlands where 75% of claims involved women.¹⁹ This finding might reflect that SVI is more common in women, thus more operations are performed on women.² It is also possible that disappointing cosmetic result may motivate women to file claims more readily than men.

A majority of compensated injuries involved procedures for GSV. This is probably due to the fact that SSV insufficiency is rarer.²⁰ Failure to remove all varicosities was compensated as PI for the operations carried out in 2003 and 2005. It is possible that more recent decisions would not consider patient’s experienced insufficient removal of side branches as a compensable injury as treatment of the truncal disease is, nowadays, considered the main focus of the approach.²¹

Treatment of complicated disease (C4-C6) leaves patients with more residual symptoms and skin changes. Therefore early treatment of SVI is recommended.²² Earlier initiation of treatment increases the number of treatable patients and requires more resources.

Approximately 20% of varicose veins operations involve bilateral GSV disease.²³ One third of our patients had a bilateral operation. This corresponds to that found in the Netherlands claim study which reported 36% of patients had a bilateral operation.¹⁹ The advantages of a bilateral operation are that anesthesia and the convalescence period only occur once. The drawback is that the operating time is longer. This has been speculated to lead to increased risk of thromboembolic events and infection but in several studies bilateral open surgery has involved no increased risks.^23,24

In the Netherlands only 14.4% had a reintervention compared to one third of our patients whom had already previously had undergone an operation to treat varicose vein. Scarring from previous operations increases complication risks especially in open surgery. Endovenous operations are less complication prone in reintervention patients.²⁵

Circumstances

Half of the compensated injuries occurred in either university or central hospitals. This reflects the fact that the larger units also perform more procedures. Nowadays, open procedures are often preferred only when endovenous techniques are not available.² This can be the case in smaller hospitals, where the annual number of procedures is limited and personnel experienced in endovenous procedures is lacking as is the needed equipment.

Surgeons of other specialties performed more than a third of the procedures during the study period. In PIC’s statistics vascular surgery became a separate specialty in 2004. Before that all claims involving treatment of SVI were recorded under general surgery. Previously the treatment of SVI had mostly been performed by general surgeons but after vascular surgery became a specialty of its own the majority of procedures involving SVI are now performed by vascular surgeons.

One third (33.3%) of operations were performed by surgeons in training. Similar trends were seen in the Netherlands where 41.4% of the operations were done by registrars.¹⁹ A majority of operations were performed by fully trained surgeons, thus a lack of experience should not be the only explanation for compensated injuries.

Nowadays, both the national treatment guideline⁸ and European guideline² are followed in Finland. Both state that preliminary ultrasound examination is obligatory prior to the treatment of SVI to evaluate the correct treatment modality. The importance of the benefits of ultrasound can be demonstrated by the fact that two patients who had no ultra-sound prior to treatment had to undergo a re-operation.

Types of injuries

There were no deaths in our dataset but several injuries were life threatening. Necrotizing fasciitis is a severe and dreaded complication, which can occur after any surgery. The road to recovery is often long as was experienced by two of our patients who were infected. Varicose vein surgery is not a high risk surgery for necrotizing fasciitis and with the increase of endovenous SVI operations they are likely to become exceedingly rare.²⁶ No infection injuries involving endovenous techniques were compensated in our dataset.

In the Netherlands, typical reasons that led to accepted insurance claim were nerve injury (26.8%), deep vein injury(22.0%), and lack of communication.¹⁹ In the UK, typical complications that led to PI were nerve damage (47.4%), vessel injury (21.1%) and intraoperative burns.¹⁶ In our study, 11.1% of the injuries involved nerve injuries and 22.2% deep vein injuries. The percentage of nerve injuries is clearly lower than in the UK and the Netherlands but the number of vessel injuries is very similar and those reports covered earlier study periods. This might be explained by PIC’s compensation criteria. Nerve injuries with minor consequences such as a slight decrease in the sense of touch are not usually compensated.

Injuries to adjacent vascular structures during SVI surgery can be life threatening.²⁷ In previous studies injuries to the femoral and the popliteal veins and also to the femoral artery have been reported. The incidence of such injuries is reported to be below 1% in varicose vein operations.²⁷ With increased minimally invasive techniques it is likely that these injuries will be exceptional.

New techniques may also present novel complications as new skills and procedures have to be learned and mastered. None of the injuries involving endovenous treatment were life threatening. Both of the retained foreign material injuries involved endovenous laser ablation. As the equipment was likely relatively unfamiliar to both the operator and the nurse, the loss of the guidance sheath and guide wire were not detected. It was also noteworthy that the possibility of such complication had clearly not crossed anybody’s mind even though patients had sought help for their symptoms after the operation. As endovenous ablation procedures are often ambulatory, safety protocols such as safety checklists may not be included in routine work. These procedures might also be assisted by nurses who are less familiar with operating theatre protocols.

Study limitations

Closed claim analysis has limitations. As all retrospective studies, we are dependent upon the data recorded in charts. It is likely that the accepted claims represent only a portion all adverse events as not all patients file a claim after experiencing a PI. Inadequate knowledge about the insurance system may reduce the likelihood of filing claims. On the other hand, the PIC registry covers the whole of country and is therefore highly representative of Finland’s PIs.

It should be noted that the PIC registry is not a registry of complications in Finland per se but only of cases in which the patient has filed a claim for a suspected PI. The focus is in the compensated claims. The incidence of complications cannot be determined from this registry.

Conclusions

Patient injuries relating to the frequency of performed SVI procedures occurred only rarely. A majority of PIs in the treatment of SVI involved open surgery. Increased endovenous treatment has reduced the number of submitted claims.

Injuries were identifiable during all stages of care, perioperative injuries related to open surgery were the most common. The percentage of serious injuries was low. Endovenous treatment has unique injuries that should be kept in mind.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Ethical approval

No separate approval from ethics committee was necessary as this study was a retrospective analysis of insurance charts.

Guarantor

ML.

Contributorship

ML, KB and PH researched literature and conceived the study. ML and VN gathered the data. ML wrote the first draft of the manuscript. All authors reviewed and edited the manuscript and approved the final version of the manuscript.

Acknowledgements

ORCID iD

M Laukkavirta

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